Crystallization in high-level waste glass: A review of glass theory and noteworthy literature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christian, J. H.

2015-08-18

There is a fundamental need to continue research aimed at understanding nepheline and spinel crystal formation in high-level waste (HLW) glass. Specifically, the formation of nepheline solids (K/NaAlSiO 4) during slow cooling of HLW glass can reduce the chemical durability of the glass, which can cause a decrease in the overall durability of the glass waste form. The accumulation of spinel solids ((Fe, Ni, Mn, Zn)(Fe, Cr) 2O 4), while not detrimental to glass durability, can cause an array of processing problems inside HLW glass melters. In this review, the fundamental differences between glass and solid-crystals are explained using kinetic,more » thermodynamic, and viscosity arguments, and several highlights of glass-crystallization research, as it pertains to high-level waste vitrification, are described. In terms of mitigating spinel in the melter and both spinel and nepheline formation in the canister, the complexity of HLW glass and the intricate interplay between thermal, chemical, and kinetic factors further complicates this understanding. However, new experiments seeking to elucidate the contributing factors of crystal nucleation and growth in waste glass, and the compilation of data from older experiments, may go a long way towards helping to achieve higher waste loadings while developing more efficient processing strategies. Higher waste loadings and more efficient processing strategies will reduce the overall HLW Hanford Tank Waste Treatment and Immobilization Plant (WTP) vitrification facilities mission life.« less

Method for solidification of radioactive and other hazardous waste

DOEpatents

Anshits, Alexander G.; Vereshchagina, Tatiana A.; Voskresenskaya, Elena N.; Kostin, Eduard M.; Pavlov, Vyacheslav F.; Revenko, Yurii A.; Tretyakov, Alexander A.; Sharonova, Olga M.; Aloy, Albert S.; Sapozhnikova, Natalia V.; Knecht, Dieter A.; Tranter, Troy J.; Macheret, Yevgeny

2002-01-01

Solidification of liquid radioactive waste, and other hazardous wastes, is accomplished by the method of the invention by incorporating the waste into a porous glass crystalline molded block. The porous block is first loaded with the liquid waste and then dehydrated and exposed to thermal treatment at 50-1,000.degree. C. The porous glass crystalline molded block consists of glass crystalline hollow microspheres separated from fly ash (cenospheres), resulting from incineration of fossil plant coals. In a preferred embodiment, the porous glass crystalline blocks are formed from perforated cenospheres of grain size -400+50, wherein the selected cenospheres are consolidated into the porous molded block with a binder, such as liquid silicate glass. The porous blocks are then subjected to repeated cycles of saturating with liquid waste, and drying, and after the last cycle the blocks are subjected to calcination to transform the dried salts to more stable oxides. Radioactive liquid waste can be further stabilized in the porous blocks by coating the internal surface of the block with metal oxides prior to adding the liquid waste, and by coating the outside of the block with a low-melting glass or a ceramic after the waste is loaded into the block.

Final Report. Baseline LAW Glass Formulation Testing, VSL-03R3460-1, Rev. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muller, Isabelle S.; Pegg, Ian L.; Gan, Hao

2015-06-18

The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements.

Glass Waste Forms for Oak Ridge Tank Wastes: Fiscal Year 1998 Report for Task Plan SR-16WT-31, Task B

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andrews, M.K.

1999-05-10

Using ORNL information on the characterization of the tank waste sludges, SRTC performed extensive bench-scale vitrification studies using simulants. Several glass systems were tested to ensure the optimum glass composition (based on the glass liquidus temperature, viscosity and durability) is determined. This optimum composition will balance waste loading, melt temperature, waste form performance and disposal requirements. By optimizing the glass composition, a cost savings can be realized during vitrification of the waste. The preferred glass formulation was selected from the bench-scale studies and recommended to ORNL for further testing with samples of actual OR waste tank sludges.

CHEMICAL ANALYSIS OF SIMULATED HIGH LEVEL WASTE GLASSES TO SUPPORT SULFATE SOLUBILITY MODELING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Marra, J.

2014-08-14

The U.S. Department of Energy (DOE), Office of Environmental Management (EM) is sponsoring an international, collaborative project to develop a fundamental model for sulfate solubility in nuclear waste glass. The solubility of sulfate has a significant impact on the achievable waste loading for nuclear waste forms both within the DOE complex and to some extent at U.K. sites. The development of enhanced borosilicate glass compositions with improved sulfate solubility will allow for higher waste loadings and accelerated cleanup missions. Much of the previous work on improving sulfate retention in waste glasses has been done on an empirical basis, making itmore » difficult to apply the findings to future waste compositions despite the large number of glass systems studied. A more fundamental, rather than empirical, model of sulfate solubility in glass, under development at Sheffield Hallam University (SHU), could provide a solution to the issues of sulfate solubility. The model uses the normalized cation field strength index as a function of glass composition to predict sulfate capacity, and has shown early success for some glass systems. The objective of the current scope is to mature the sulfate solubility model to the point where it can be used to guide glass composition development for DOE waste vitrification efforts, allowing for enhanced waste loadings and waste throughput. A series of targeted glass compositions was selected to resolve data gaps in the current model. SHU fabricated these glasses and sent samples to the Savannah River National Laboratory (SRNL) for chemical composition analysis. SHU will use the resulting data to enhance the sulfate solubility model and resolve any deficiencies. In this report, SRNL provides chemical analyses for simulated waste glasses fabricated SHU in support of sulfate solubility model development. A review of the measured compositions revealed that there are issues with the B{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} concentrations missing their targeted values by a significant amount for several of the study glasses. SHU is reviewing the fabrication of these glasses and the chemicals used in batching them to identify the source of these issues. The measured sulfate concentrations were all below their targeted values. This is expected, as the targeted concentrations likely exceeded the solubility limit for sulfate in these glass compositions. Some volatilization of sulfate may also have occurred during fabrication of the glasses. Measurements of the other oxides in the study glasses were reasonably close to their targeted values« less

Technical Status Report: Preliminary Glass Formulation Report for INEEL HAW. Revision 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peeler, D.; Reamer, I.; Vienna, J.

1998-03-01

Preliminary glass formulation work has been initiated at Pacific Northwest National Laboratory (PNNL) and the Savannah River Technology Center (SRTC) to support immobilization efforts of Idaho National Engineering and Environmental Laboratory (INEEL) high activity waste (HAW). Based on current pretreatment flow sheet assumptions, several glasses were fabricated and tested using an average `All Blend` waste stream composition which is dominated by the presence of ZrO{sub 2} (i.e., approximately 80 wt percent). The results of this initial work show that immobilization via vitrification is a viable option for a specific INEEL HAW waste stream. Waste loadings of at least 19 wtmore » percent can be achieved for the `All Blend` stream while maintaining targeted processing and product performance criteria. This waste loading translates into a ZrO{sub 2} content in excess of 15 wt percent in the final glass waste form. Frits developed for this work are based in the alkali borosilicate system. Although the results indicate that vitrification can be used to immobilize the `All Blend` waste stream, the glass compositions are by no means optimized.« less

SOLIDIFICATION OF THE HANFORD LAW WASTE STREAM PRODUCED AS A RESULT OF NEAR-TANK CONTINUOUS SLUDGE LEACHING AND SODIUM HYDROXIDE RECOVERY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reigel, M.; Johnson, F.; Crawford, C.

2011-09-20

The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge canmore » be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the quenched glasses. However, the waste form failed to meet the vapor hydration test criteria listed in the WTP contract. In addition, the waste loading in the phosphate glasses were not as high as other candidate waste forms. Vitrification of HLW waste as borosilicate glass is a proven process; however the HLW and LAW streams at Hanford can vary significantly from waste currently being immobilized. The ccc glasses show lower release rates for B and Na than the quenched glasses and all glasses meet the acceptance criterion of < 4 g/L. Glass samples spiked with Re{sub 2}O{sub 7} also passed the PCT test. However, further vapor hydration testing must be performed since all the samples cracked and the test could not be performed. The waste loading of the iron phosphate and borosilicate glasses are approximately 20 and 25% respectively. The steam reforming process produced the predicted waste form for both the high and low aluminate waste streams. The predicted waste loadings for the monolithic samples is approximately 39%, which is higher than the glass waste forms; however, at the time of this report, no monolithic samples were made and therefore compliance with the PA cannot be determined. The waste loading in the geopolymer is approximately 40% but can vary with the sodium hydroxide content in the waste stream. Initial geopolymer mixes revealed compressive strengths that are greater than 500 psi for the low aluminate mixes and less than 500 psi for the high aluminate mixes. Further work testing needs to be performed to formulate a geopolymer waste form made using a high aluminate salt solution. A cementitious waste form has the advantage that the process is performed at ambient conditions and is a proven process currently in use for LAW disposal. The Saltstone/Cast Stone formulated using low and high aluminate salt solutions retained at least 97% of the Re that was added to the mix as a dopant. While this data is promising, additional leaching testing must be performed to show compliance with the PA. Compressive strength tests must also be performed on the Cast Stone monoliths to verify PA compliance. Based on testing performed for this report, the borosilicate glass and Cast Stone are the recommended waste forms for further testing. Both are proven technologies for radioactive waste disposal and the initial testing using simulated Hanford LAW waste shows compliance with the PA. Both are resistant to leaching and have greater than 25% waste loading.« less

The role of frit in nuclear waste vitrification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, J.D.; Smith, P.A.; Dorn, D.A.

1994-04-01

Vitrification of nuclear waste requires additives which are often vitrified independently to form a frit. Frit composition is formulated to meet the needs of glass composition and processing. The effects of frit on melter feed and melt processing, glass acceptance, and waste loading is of practical interest in understanding the trade-offs associated with the competing demands placed on frit composition. Melter feed yield stress, viscosity and durability of frits and corresponding waste glasses as well as the kinetics of elementary melting processes have been measured. The results illustrate the competing requirements on frit. Four frits (FY91, FY93, HW39-4, and SR202)more » and simulated neutralized current acid waste (NCAW) were used in this study. The experimental evidence shows that optimization of frit for one processing related property often results in poorer performance for the remaining properties. The difficulties associated with maximum waste loading and durability are elucidated for glasses which could be processed using technology available for the previously proposed Hanford Waste Vitrification Plant.« less

Glass Property Models, Constraints, and Formulation Approaches for Vitrification of High-Level Nuclear Wastes at the US Hanford Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Dong-Sang

2015-03-02

The legacy nuclear wastes stored in underground tanks at the US Department of Energy’s Hanford site is planned to be separated into high-level waste and low-activity waste fractions and vitrified separately. Formulating optimized glass compositions that maximize the waste loading in glass is critical for successful and economical treatment and immobilization of nuclear wastes. Glass property-composition models have been developed and applied to formulate glass compositions for various objectives for the past several decades. The property models with associated uncertainties and combined with composition and property constraints have been used to develop preliminary glass formulation algorithms designed for vitrification processmore » control and waste form qualification at the planned waste vitrification plant. This paper provides an overview of current status of glass property-composition models, constraints applicable to Hanford waste vitrification, and glass formulation approaches that have been developed for vitrification of hazardous and highly radioactive wastes stored at the Hanford site.« less

Final Report. LAW Glass Formulation to Support AP-101 Actual Waste Testing, VSL-03R3470-2, Rev. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muller, I. S.; Pegg, I. L.; Rielley, Elizabeth

2015-06-22

The main objective of the work was to develop and select a glass formulation for vitrification testing of the actual waste sample of LAW AP-101 at Battelle - Pacific Northwest Division (PNWD). Other objectives of the work included preparation and characterization of glasses to demonstrate compliance with contract and processing requirements, evaluation of the ability to achieve waste loading requirements, testing to demonstrate compatibility of the glass melts with melter materials of construction, comparison of the properties of simulant and actual waste glasses, and identification of glass formulation issues with respect to contract specifications and processing requirements.

Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105 And AN-103) By Fluidized Bed Steam Reformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol; Herman, Connie; Crawford, Charles

One of the immobilization technologies under consideration as a Supplemental Treatment for Hanford’s Low Activity Waste (LAW) is Fluidized Bed Steam Reforming (FBSR). The FBSR technology forms a mineral waste form at moderate processing temperatures thus retaining and atomically bonding the halides, sulfates, and technetium in the mineral phases (nepheline, sodalite, nosean, carnegieite). Additions of kaolin clay are used instead of glass formers and the minerals formed by the FBSR technology offers (1) atomic bonding of the radionuclides and constituents of concern (COC) comparable to glass, (2) short and long term durability comparable to glass, (3) disposal volumes comparable tomore » glass, and (4) higher Na2O and SO{sub 4} waste loadings than glass. The higher FBSR Na{sub 2}O and SO{sub 4} waste loadings contribute to the low disposal volumes but also provide for more rapid processing of the LAW. Recent FBSR processing and testing of Hanford radioactive LAW (Tank SX-105 and AN-103) waste is reported and compared to previous radioactive and non-radioactive LAW processing and testing.« less

Demonstration of sulfur solubility determinations in high waste loading, low-activity waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.

2016-04-25

A method recommended by Pacific Northwest National Laboratory (PNNL) for sulfate solubility determinations in simulated low-activity waste glasses was demonstrated using three compositions from a recent Hanford high waste loading glass study. Sodium and sulfate concentrations in the glasses increased after each re-melting step. Visual observations of the glasses during the re-melting process reflected the changes in composition. The measured compositions showed that the glasses met the targeted values. The amount of SO 3 retained in the glasses after washing was relatively high, ranging from 1.6 to 2.6 weight percent (wt %). Measured SnO 2 concentrations were notably low inmore » all of the study glasses. The composition of the wash solutions should be measured in future work to determine whether SnO 2 is present with the excess sulfate washed from the glass. Increases in batch size and the amount of sodium sulfate added did not have a measureable impact on the amount of sulfate retained in the glass, although this was tested for only a single glass composition. A batch size of 250 g and a sodium sulfate addition targeting 7 wt %, as recommended by PNNL, will be used in future experiments.« less

RESULTS OF THE FY09 ENHANCED DOE HIGH LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, F.; Edwards, T.

2010-06-23

High-level waste (HLW) throughput (i.e., the amount of waste processed per unit time) is a function of two critical parameters: waste loading (WL) and melt rate. For the Waste Treatment and Immobilization Plant (WTP) at the Hanford Site and the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), increasing HLW throughput would significantly reduce the overall mission life cycle costs for the Department of Energy (DOE). The objective of this task is to develop data, assess property models, and refine or develop the necessary models to support increased WL of HLW at SRS. It is a continuationmore » of the studies initiated in FY07, but is under the specific guidance of a Task Change Request (TCR)/Work Authorization received from DOE headquarters (Project Number RV071301). Using the data generated in FY07, FY08 and historical data, two test matrices (60 glasses total) were developed at the Savannah River National Laboratory (SRNL) in order to generate data in broader compositional regions. These glasses were fabricated and characterized using chemical composition analysis, X-ray Diffraction (XRD), viscosity, liquidus temperature (TL) measurement and durability as defined by the Product Consistency Test (PCT). The results of this study are summarized below: (1) In general, the current durability model predicts the durabilities of higher waste loading glasses quite well. A few of the glasses exhibited poorer durability than predicted. (2) Some of the glasses exhibited anomalous behavior with respect to durability (normalized leachate for boron (NL [B])). The quenched samples of FY09EM21-02, -07 and -21 contained no nepheline or other wasteform affecting crystals, but have unacceptable NL [B] values (> 10 g/L). The ccc sample of FY09EM21-07 has a NL [B] value that is more than one half the value of the quenched sample. These glasses also have lower concentrations of Al{sub 2}O{sub 3} and SiO{sub 2}. (3) Five of the ccc samples (EM-13, -14, -15, -29 and -30) completely crystallized with both magnetite and nepheline, and still had extremely low NL [B] values. These particular glasses have more CaO present than any of the other glasses in the matrix. It appears that while all of the glasses contain nepheline, the NL [B] values decrease as the CaO concentration increases from 2.3 wt% to 4.3 wt%. A different form of nepheline may be created at higher concentrations of CaO that does not significantly reduce glass durability. (4) The T{sub L} model appears to be under-predicting the measured values of higher waste loading glasses. Trends in T{sub L} with composition are not evident in the data from these studies. (5) A small number of glasses in the FY09 matrix have measured viscosities that are much lower than the viscosity range over which the current model was developed. The decrease in viscosity is due to a higher concentration of non-bridging oxygens (NBO). A high iron concentration is the cause of the increase in NBO. Durability, viscosity and T{sub L} data collected during FY07 and FY09 that specifically targeted higher waste loading glasses was compiled and assessed. It appears that additional data may be required to expand the coverage of the T{sub L} and viscosity models for higher waste loading glasses. In general, the compositional regions of the higher waste loading glasses are very different than those used to develop these models. On the other hand, the current durability model seems to be applicable to the new data. At this time, there is no evidence to modify this model; however additional experimental studies should be conducted to determine the cause of the anomalous durability data.« less

Road Map for Development of Crystal-Tolerant High Level Waste Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matyas, Josef; Vienna, John D.; Peeler, David

This road map guides the research and development for formulation and processing of crystal-tolerant glasses, identifying near- and long-term activities that need to be completed over the period from 2014 to 2019. The primary objective is to maximize waste loading for Hanford waste glasses without jeopardizing melter operation by crystal accumulation in the melter or melter discharge riser. The potential applicability to the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF) is also addressed in this road map.

Impacts of Process and Prediction Uncertainties on Projected Hanford Waste Glass Amount

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gervasio, V.; Kim, D. S.; Vienna, J. D.

Analyses were performed to evaluate the impacts of using the advanced glass models, constraints, and uncertainty descriptions on projected Hanford glass mass. The maximum allowable waste oxide loading (WOL) was estimated for waste compositions while simultaneously satisfying all applicable glass property and composition constraints with sufficient confidence. Different components of prediction and composition/process uncertainties were systematically included in the calculations to evaluate their impacts on glass mass. The analyses estimated the production of 23,360 MT of immobilized high-level waste (IHLW) glass when no uncertainties were taken into account. Accounting for prediction and composition/process uncertainties resulted in 5.01 relative percent increasemore » in estimated glass mass of 24,531 MT. Roughly equal impacts were found for prediction uncertainties (2.58 RPD) and composition/process uncertainties (2.43 RPD). The immobilized low-activity waste (ILAW) mass was predicted to be 282,350 MT without uncertainty and with waste loading “line” rules in place. Accounting for prediction and composition/process uncertainties resulted in only 0.08 relative percent increase in estimated glass mass of 282,562 MT. Without application of line rules the glass mass decreases by 10.6 relative percent (252,490 MT) for the case with no uncertainties. Addition of prediction uncertainties increases glass mass by 1.32 relative percent and the addition of composition/process uncertainties increase glass mass by an additional 7.73 relative percent (9.06 relative percent increase combined). The glass mass estimate without line rules (275,359 MT) was 2.55 relative percent lower than that with the line rules (282,562 MT), after accounting for all applicable uncertainties.« less

Ceramic Single Phase High-Level Nuclear Waste Forms: Hollandite, Perovskite, and Pyrochlore

NASA Astrophysics Data System (ADS)

Vetter, M.; Wang, J.

2017-12-01

The lack of viable options for the safe, reliable, and long-term storage of nuclear waste is one of the primary roadblocks of nuclear energy's sustainable future. The method being researched is the incorporation and immobilization of harmful radionuclides (Cs, Sr, Actinides, and Lanthanides) into the structure of glasses and ceramics. Borosilicate glasses are the main waste form that is accepted and used by today's nuclear industry, but they aren't the most efficient in terms of waste loading, and durability is still not fully understood. Synroc-phase ceramics (i.e. hollandite, perovskite, pyrochlore, zirconolite) have many attractive qualities that glass waste forms do not: high waste loading, moderate thermal expansion and conductivity, high chemical durability, and high radiation stability. The only downside to ceramics is that they are more complex to process than glass. New compositions can be discovered by using an Artificial Neural Network (ANN) to have more options to optimize the composition, loading for performance by analyzing the non-linear relationships between ionic radii, electronegativity, channel size, and a mineral's ability to incorporate radionuclides into its structure. Cesium can be incorporated into hollandite's A-site, while pyrochlore and perovskite can incorporate actinides and lanthanides into their A-site. The ANN is used to predict new compositions based on hollandite's channel size, as well as the A-O bond distances of pyrochlore and perovskite, and determine which ions can be incorporated. These new compositions will provide more options for more experiments to potentially improve chemical and thermodynamic properties, as well as increased waste loading capabilities.

Epsilon Metal Waste Form for Immobilization of Noble Metals from Used Nuclear Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crum, Jarrod V.; Strachan, Denis M.; Rohatgi, Aashish

2013-10-01

Epsilon metal (ε-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass and thus the processing problems related there insolubility in glass. This work focused on the processing aspects of the epsilonmore » metal waste form development. Epsilon metal is comprised of refractory metals resulting in high reaction temperatures to form the alloy, expected to be 1500 - 2000°C making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).« less

Epsilon metal waste form for immobilization of noble metals from used nuclear fuel

NASA Astrophysics Data System (ADS)

Crum, Jarrod V.; Strachan, Denis; Rohatgi, Aashish; Zumhoff, Mac

2013-10-01

Epsilon metal (ɛ-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass, thus the processing problems related to their insolubility in glass. This work focused on the processing aspects of the epsilon metal waste form development. Epsilon metal is comprised of refractory metals resulting in high alloying temperatures, expected to be 1500-2000 °C, making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).

Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

DOEpatents

Boatner, Lynn A.; Sales, Brian C.

1989-01-01

Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

Memo, "Incorporation of HLW Glass Shell V2.0 into the Flowsheets," to ED Lee, CCN: 184905, October 20, 2009

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gimpel, Rodney F.; Kruger, Albert A.

2013-12-18

Efforts are being made to increase the efficiency and decrease the cost of vitrifying radioactive waste stored in tanks at the U.S. Department of Energy Hanford Site. The compositions of acceptable and processable high-level waste (HL W) glasses need to be optimized to minimize the waste-form volume and, hence, to reduce cost. A database of glass properties of waste glass and associated simulated waste glasses was collected and documented in PNNL 18501, Glass Property Data and Models for Estimating High-Level Waste Glass Volume and glass property models were curve-fitted to the glass compositions. A routine was developed that estimates HLmore » W glass volumes using the following glass property models: II Nepheline, II One-Percent Crystal Temperature (T1%), II Viscosity (11) II Product Consistency Tests (PCT) for boron, sodium, and lithium, and II Liquidus Temperature (TL). The routine, commonly called the HL W Glass Shell, is presented in this document. In addition to the use of the glass property models, glass composition constraints and rules, as recommend in PNNL 18501 and in other documents (as referenced in this report) were incorporated. This new version of the HL W Glass Shell should generally estimate higher waste loading in the HL W glass than previous versions.« less

ILAW Glass Testing for Disposal at IDF: Phase 1 Testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papathanassiu, Adonia; Muller, Isabelle S.; Brandys, Marek

2011-04-11

This document reports the results of the testing of phase 1 ORP LAW (low activity waste) glasses, also identified as enhanced LAW glasses. Testing involved are SPFT (Single Pass Flow Through), VHT (Vapor Hydration Test), and PCT (Product Consistency Test), along with the analytical tests (XRD and SEM-EDS). This report contains the data of the high waste loading ORP LAW glasses that will be used for the performance assessment of the IDF (Integrated Disposal Facility).

Crystallization in high-level waste glass: A review of glass theory and noteworthy literature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christian, J. H.

2015-08-01

There is a fundamental need to continue research aimed at understanding nepheline and spinel crystal formation in high-level waste (HLW) glass. Specifically, the formation of nepheline solids (K/NaAlSiO₄) during slow cooling of HLW glass can reduce the chemical durability of the glass, which can cause a decrease in the overall durability of the glass waste form. The accumulation of spinel solids ((Fe, Ni, Mn, Zn)(Fe,Cr)₂O₄), while not detrimental to glass durability, can cause an array of processing problems inside of HLW glass melters. In this review, the fundamental differences between glass and solid-crystals are explained using kinetic, thermodynamic, and viscositymore » arguments, and several highlights of glass-crystallization research, as it pertains to high-level waste vitrification, are described. In terms of mitigating spinel in the melter and both spinel and nepheline formation in the canister, the complexity of HLW glass and the intricate interplay between thermal, chemical, and kinetic factors further complicates this understanding. However, new experiments seeking to elucidate the contributing factors of crystal nucleation and growth in waste glass, and the compilation of data from older experiments, may go a long way towards helping to achieve higher waste loadings while developing more efficient processing strategies.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Johnson, F. C.

Increased loading of high level waste in glass can lead to crystallization within the glass. Some crystalline species, such as spinel, have no practical impact on the chemical durability of the glass, and therefore may be acceptable from both a processing and a product performance standpoint. In order to operate a melter with a controlled amount of crystallization, options must be developed for remediating an unacceptable accumulation of crystals. This report describes preliminary experiments designed to evaluate the ability to dissolve spinel crystals in simulated waste glass melts via the addition of glass forming chemicals (GFCs).

Low sintering temperature glass waste forms for sequestering radioactive iodine

DOEpatents

Nenoff, Tina M.; Krumhansl, James L.; Garino, Terry J.; Ockwig, Nathan W.

2012-09-11

Materials and methods of making low-sintering-temperature glass waste forms that sequester radioactive iodine in a strong and durable structure. First, the iodine is captured by an adsorbant, which forms an iodine-loaded material, e.g., AgI, AgI-zeolite, AgI-mordenite, Ag-silica aerogel, ZnI.sub.2, CuI, or Bi.sub.5O.sub.7I. Next, particles of the iodine-loaded material are mixed with powdered frits of low-sintering-temperature glasses (comprising various oxides of Si, B, Bi, Pb, and Zn), and then sintered at a relatively low temperature, ranging from 425.degree. C. to 550.degree. C. The sintering converts the mixed powders into a solid block of a glassy waste form, having low iodine leaching rates. The vitrified glassy waste form can contain as much as 60 wt % AgI. A preferred glass, having a sintering temperature of 500.degree. C. (below the silver iodide sublimation temperature of 500.degree. C.) was identified that contains oxides of boron, bismuth, and zinc, while containing essentially no lead or silicon.

Tensile properties of chrome tanned leather waste short fibre filled unsaturated polyester composite

NASA Astrophysics Data System (ADS)

Talib, Satariah; Romli, Ahmad Zafir; Saad, Siti Zaleha

2017-12-01

Waste leather from industries was commonly disposed via land filling or incineration where the oxidation of Cr III to Cr VI by oxidants (such as peroxides and hypohalide) can easily occur. Cr VI is well known as carcinogenic and mutagenic element where the excessive exposure to this element can be very harmful. As an alternative way, the leather waste from footwear industry was utilised as filler in unsaturated polyester composite (UPC). The leather waste was ground using 0.25 mm mesh size and used without any chemical treatment. The sample was fabricated via castingtechnique and the study was carried out at 1 wt%, 2 wt% and 3 wt% filler loading. The leather waste filled composites showed lower tensile strength and Young's modulus than the unfilled composite. The increasing loading amount of leather waste led to the decreased in tensile strength and Young's modulus. The tensile results was supported by the decreasing pattern of density result which indicates the increasing of void content as the filler loading increased. The results of glass transition temperature are also parallel to the tensile properties where the increasing filler loading had decreased the glass transition temperature. Based on the morphological observation on the fractured tensile sample, much severe filler agglomerations and higher amount of voids was observed at higher filler loading compared to the lower filler loading.

Final Report - Enhanced LAW Glass Formulation Testing, VSL-07R1130-1, Rev. 0, dated 10/05/07

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Pegg, I. L.; Matlack, K. S.

2013-11-13

The principal objective of this work was to extend the glass formulation methodology developed in the earlier work [2, 5, 6] for Envelope A, B and C waste compositions for development of compliant glass compositions targeting five high sodium-sulfur waste loading regions. This was accomplished through a combination of crucible-scale tests, and tests on the DM10 melter system. The DM10 was used for several previous tests on LAW compositions to determine the maximum feed sulfur concentrations that can be processed without forming secondary sulfate phases on the surface of the melt pool. This melter is the most efficient melter platformmore » for screening glass compositions over a wide range of sulfate concentrations and therefore was selected for the present tests. The tests were conducted to provide information on melter processing characteristics and off-gas data, including sulfur incorporation and partitioning. As described above, the main objective was to identify the limits of waste loading in compliant glass formulations spanning the range of expected Na{sub 2}O and SO{sub 3} concentrations in the LAW glasses.« less

EXAFS/XANES studies of plutonium-loaded sodalite/glass waste forms

NASA Astrophysics Data System (ADS)

Richmann, Michael K.; Reed, Donald T.; Kropf, A. Jeremy; Aase, Scott B.; Lewis, Michele A.

2001-09-01

A sodalite/glass ceramic waste form is being developed to immobilize highly radioactive nuclear wastes in chloride form, as part of an electrochemical cleanup process. Two types of simulated waste forms were studied: where the plutonium was alone in an LiCl/KCl matrix and where simulated fission-product elements were added representative of the electrometallurgical treatment process used to recover uranium from spent nuclear fuel also containing plutonium and a variety of fission products. Extended X-ray absorption fine structure spectroscopy (EXAFS) and X-ray absorption near-edge spectroscopy (XANES) studies were performed to determine the location, oxidation state, and particle size of the plutonium within these waste form samples. Plutonium was found to segregate as plutonium(IV) oxide with a crystallite size of at least 4.8 nm in the non-fission-element case and 1.3 nm with fission elements present. No plutonium was observed within the sodalite in the waste form made from the plutonium-loaded LiCl/KCl eutectic salt. Up to 35% of the plutonium in the waste form made from the plutonium-loaded simulated fission-product salt may be segregated with a heavy-element nearest neighbor other than plutonium or occluded internally within the sodalite lattice.

A Review of Iron Phosphate Glasses and Recommendations for Vitrifying Hanford Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Delbert E. Ray; Chandra S. Ray

2013-11-01

This report contains a comprehensive review of the research conducted, world-wide, on iron phosphate glass over the past ~30 years. Special attention is devoted to those iron phosphate glass compositions which have been formulated for the purpose of vitrifying numerous types of nuclear waste, with special emphasis on the wastes stored in the underground tanks at Hanford WA. Data for the structural, chemical, and physical properties of iron phosphate waste forms are reviewed for the purpose of understanding their (a) outstanding chemical durability which meets all current DOE requirements, (b) high waste loadings which can exceed 40 wt% (up tomore » 75 wt%) for several Hanford wastes, (c) low melting temperatures, can be as low as 900°C for certain wastes, and (d) high tolerance for “problem” waste components such as sulfates, halides, and heavy metals (chromium, actinides, noble metals, etc.). Several recommendations are given for actions that are necessary to smoothly integrate iron phosphate glass technology into the present waste treatment plans and vitrification facilities at Hanford.« less

Office of River Protection Advanced Low-Activity Waste Glass Research and Development Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peeler, David K.; Kim, Dong-Sang; Vienna, John D.

2015-11-01

The U.S. Department of Energy Office of River Protection (ORP) has initiated and leads an integrated Advanced Waste Glass (AWG) program to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product performance requirements. The integrated ORP program is focused on providing a technical, science-based foundation for making key decisions regarding the successful operation of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) facilities in the context of an optimized River Protection Project (RPP) flowsheet. The fundamental data stemming from this program will support development of advanced glass formulations, keymore » product performance and process control models, and tactical processing strategies to ensure safe and successful operations for both the low-activity waste (LAW) and high-level waste vitrification facilities. These activities will be conducted with the objective of improving the overall RPP mission by enhancing flexibility and reducing cost and schedule. The purpose of this advanced LAW glass research and development plan is to identify the near-term, mid-term, and longer-term research and development activities required to develop and validate advanced LAW glasses, property-composition models and their uncertainties, and an advanced glass algorithm to support WTP facility operations, including both Direct Feed LAW and full pretreatment flowsheets. Data are needed to develop, validate, and implement 1) new glass property-composition models and 2) a new glass formulation algorithm. Hence, this plan integrates specific studies associated with increasing the Na2O and SO3/halide concentrations in glass, because these components will ultimately dictate waste loadings for LAW vitrification. Of equal importance is the development of an efficient and economic strategy for 99Tc management. Specific and detailed studies are being implemented to understand the fate of Tc throughout the WTP flowsheet and the underlying mechanisms that dictate its partitioning between streams within the LAW vitrification facility. These studies are aimed at increasing the single-pass Tc retention in glass and the potential use of high-temperature mineral phases to capture Tc. The Tc-bearing mineral phases would be thermally stable and resistant to Tc release during feed melting reactions or they could serve as alternative waste forms. The LAW glass research and development is focused on reducing the total volume of LAW glass produced and minimizing the impact of (or potentially eliminating) the need for recycle.« less

Glass Property Models and Constraints for Estimating the Glass to be Produced at Hanford by Implementing Current Advanced Glass Formulation Efforts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, John D.; Kim, Dong-Sang; Skorski, Daniel C.

2013-07-01

Recent glass formulation and melter testing data have suggested that significant increases in waste loading in HLW and LAW glasses are possible over current system planning estimates. The data (although limited in some cases) were evaluated to determine a set of constraints and models that could be used to estimate the maximum loading of specific waste compositions in glass. It is recommended that these models and constraints be used to estimate the likely HLW and LAW glass volumes that would result if the current glass formulation studies are successfully completed. It is recognized that some of the models are preliminarymore » in nature and will change in the coming years. Plus the models do not currently address the prediction uncertainties that would be needed before they could be used in plant operations. The models and constraints are only meant to give an indication of rough glass volumes and are not intended to be used in plant operation or waste form qualification activities. A current research program is in place to develop the data, models, and uncertainty descriptions for that purpose. A fundamental tenet underlying the research reported in this document is to try to be less conservative than previous studies when developing constraints for estimating the glass to be produced by implementing current advanced glass formulation efforts. The less conservative approach documented herein should allow for the estimate of glass masses that may be realized if the current efforts in advanced glass formulations are completed over the coming years and are as successful as early indications suggest they may be. Because of this approach there is an unquantifiable uncertainty in the ultimate glass volume projections due to model prediction uncertainties that has to be considered along with other system uncertainties such as waste compositions and amounts to be immobilized, split factors between LAW and HLW, etc.« less

Office of River Protection Advanced Low-Activity Waste Glass Research and Development Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, A. A.; Peeler, D. K.; Kim, D. S.

2015-11-23

The U.S. Department of Energy Office of River Protection (ORP) has initiated and leads an integrated Advanced Waste Glass (AWG) program to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product performance requirements. The integrated ORP program is focused on providing a technical, science-based foundation for making key decisions regarding the successful operation of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) facilities in the context of an optimized River Protection Project (RPP) flowsheet. The fundamental data stemming from this program will support development of advanced glass formulations, keymore » product performance and process control models, and tactical processing strategies to ensure safe and successful operations for both the low-activity waste (LAW) and high-level waste vitrification facilities. These activities will be conducted with the objective of improving the overall RPP mission by enhancing flexibility and reducing cost and schedule.« less

Removal of radioactive and other hazardous material from fluid waste

DOEpatents

Tranter, Troy J [Idaho Falls, ID; Knecht, Dieter A [Idaho Falls, ID; Todd, Terry A [Aberdeen, ID; Burchfield, Larry A [W. Richland, WA; Anshits, Alexander G [Krasnoyarsk, RU; Vereshchagina, Tatiana [Krasnoyarsk, RU; Tretyakov, Alexander A [Zheleznogorsk, RU; Aloy, Albert S [St. Petersburg, RU; Sapozhnikova, Natalia V [St. Petersburg, RU

2006-10-03

Hollow glass microspheres obtained from fly ash (cenospheres) are impregnated with extractants/ion-exchangers and used to remove hazardous material from fluid waste. In a preferred embodiment the microsphere material is loaded with ammonium molybdophosphonate (AMP) and used to remove radioactive ions, such as cesium-137, from acidic liquid wastes. In another preferred embodiment, the microsphere material is loaded with octyl(phenyl)-N-N-diisobutyl-carbamoylmethylphosphine oxide (CMPO) and used to remove americium and plutonium from acidic liquid wastes.

Vitrification of ion exchange resins

DOEpatents

Cicero-Herman, Connie A.; Workman, Rhonda Jackson

2001-01-01

The present invention relates to vitrification of ion exchange resins that have become loaded with hazardous or radioactive wastes, in a way that produces a homogenous and durable waste form and reduces the disposal volume of the resin. The methods of the present invention involve directly adding borosilicate glass formers and an oxidizer to the ion exchange resin and heating the mixture at sufficient temperature to produce homogeneous glass.

Iron Phosphate Glass-Containing Hanford Waste Simulant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sevigny, Gary J.; Kimura, Marcia L.; Fischer, Christopher M.

2012-01-18

Resolution of the nation's high-level tank waste legacy requires the design, construction, and operation of large and technically complex one-of-a-kind processing waste treatment and vitrification facilities. While the ultimate limits for waste loading and melter efficiency have yet to be defined or realized, significant reductions in glass volumes for disposal and mission life may be possible with advancements in melter technologies and/or glass formulations. This test report describes the experimental results from a small-scale test using the research-scale melter (RSM) at Pacific Northwest National Laboratory (PNNL) to demonstrate the viability of iron-phosphate-based glass with a selected waste composition that ismore » high in sulfate (4.37 wt% SO3). The primary objective of the test was to develop data to support a cost-benefit analysis related to the implementation of phosphate-based glasses for Hanford low-activity waste (LAW) and/or other high-level waste streams within the U.S. Department of Energy complex. The testing was performed by PNNL and supported by Idaho National Laboratory, Savannah River National Laboratory, Missouri University of Science and Technology, and Mo-Sci Corporation.« less

VITRIFICATION SYSTEM FOR THE TREATMENT OF PLUTONIUM-BEARING WASTE AT LOS ALAMOS NATIONAL LABORATORY

DOE Office of Scientific and Technical Information (OSTI.GOV)

R. NAKAOKA; G. VEAZEY; ET AL

2001-05-01

A glove box vitrification system is being fabricated to process aqueous evaporator bottom waste generated at the Plutonium Facility (TA-55) at Los Alamos National Laboratory (LANL). The system will be the first within the U.S. Department of Energy Complex to routinely convert Pu{sup 239}-bearing transuranic (TRU) waste to a glass matrix for eventual disposal at the Waste Isolation Pilot Plant (WIPP). Currently at LANL, this waste is solidified in Portland cement. Radionuclide loading in the cementation process is restricted by potential radiolytic degradation (expressed as a wattage limit), which has been imposed to prevent the accumulation of flammable concentrations ofmore » H{sub 2} within waste packages. Waste matrixes with a higher water content (e.g., cement) are assigned a lower permissible wattage limit to compensate for their potential higher generation of H{sub 2}. This significantly increases the number of waste packages that must be prepared and shipped, thus driving up the costs of waste handling and disposal. The glove box vitrification system that is under construction will address this limitation. Because the resultant glass matrix produced by the vitrification process is non-hydrogenous, no H{sub 2} can be radiolytically evolved, and drums could be loaded to the maximum allowable limit of 40 watts. In effect, the glass waste form shifts the limiting constraint for loading disposal drums from wattage to the criticality limit of 200 fissile gram equivalents, thus significantly reducing the number of drums generated from this waste stream. It is anticipated that the number of drums generated from treatment of evaporator bottoms will be reduced by a factor of 4 annually when the vitrification system is operational. The system is currently undergoing non-radioactive operability testing, and will be fully operational in the year 2003.« less

Ash from a pulp mill boiler--characterisation and vitrification.

PubMed

Ribeiro, Ana S M; Monteiro, Regina C C; Davim, Erika J R; Fernandes, M Helena V

2010-07-15

The physical, chemical and mineralogical characterisation of the ash resulting from a pulp mill boiler was performed in order to investigate the valorisation of this waste material through the production of added-value glassy materials. The ash had a particle size distribution in the range 0.06-53 microm, and a high amount of SiO(2) (approximately 82 wt%), which was present as quartz. To favour the vitrification of the ash and to obtain a melt with an adequate viscosity to cast into a mould, different amounts of Na(2)O were added to act as fluxing agent. A batch with 80 wt% waste load melted at 1350 degrees C resulting in a homogeneous transparent green-coloured glass with good workability. The characterisation of the produced glass by differential thermal analysis and dilatometry showed that this glass presents a stable thermal behaviour. Standard leaching tests revealed that the concentration of heavy metals in the leaching solution was lower than those allowed by the Normative. As a conclusion, by vitrification of batch compositions with adequate waste load and additive content it is possible to produce an ash-based glass that may be used in similar applications as a conventional silicate glass inclusively as a building ecomaterial. 2010 Elsevier B.V. All rights reserved.

Chemical Composition Measurements of LAWA44 Glass Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Edwards, T.; Riley, W.

2016-11-15

DOE is building the Hanford Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is temporarily stored in 177 underground tanks. Both low-activity and high-level wastes will then be vitrified into borosilicate glass using Joule-heated ceramic melters. Efforts are being made to increase the loading of Hanford tank wastes in the glass. One area of work is enhancing waste glass composition/property models and broadening the compositional regions over which those models are applicable. In this report, the Savannah River National Laboratory provides chemical analysis results for severalmore » samples of a simulated low-activity waste glass, LAWA44, provided by the Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 97.9 to 102.6 wt %, indicating acceptable recovery of the glass components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %. It was noted that the measured B 2O 3 concentrations are somewhat above the targeted values for the study glasses. No obvious trends were observed with regard to the multiple melting steps used to prepare the study glasses, indicating that any potential effects of volatility were below measurable thresholds.« less

Final Report - Melt Rate Enhancement for High Aluminum HLW Glass Formulation, VSL-08R1360-1, Rev. 0, dated 12/19/08

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Pegg, I. L.; Chaudhuri, M.

2013-11-13

The principal objective of the work reported here was to develop and identify HLW glass compositions that maximize waste processing rates for the aluminum limted waste composition specified by ORP while maintaining high waste loadings and acceptable glass properties. This was accomplished through a combination of crucible-scale tests, confirmation tests on the DM100 melter system, and demonstration at pilot scale (DM1200). The DM100-BL unit was selected for these tests since it was used previously with the HLW waste streams evaluated in this study, was used for tests on HLW glass compositions to support subsequent tests on the HLW Pilot Melter,more » conduct tests to determine the effect of various glass properties (viscosity and conductivity) and oxide concentrations on glass production rates with HLW feed streams, and to assess the volatility of cesium and technetium during the vitrification of an HLW AZ-102 composition. The same melter was selected for the present tests in order to maintain comparisons between the previously collected data. These tests provide information on melter processing characteristics and off-gas data, including formation of secondary phases and partitioning. Once DM100 tests were completed, one of the compositions was selected for further testing on the DM1200; the DM1200 system has been used for processing a variety of simulated Hanford waste streams. Tests on the larger melter provide processing data at one third of the scale of the actual WTP HLW melter and, therefore, provide a more accurate and reliable assessment of production rates and potential processing issues. The work focused on maximizing waste processing rates for high aluminum HLW compositions. In view of the diversity of forms of aluminum in the Hanford tanks, tests were also conducted on the DM100 to determine the effect of changes in the form of aluminum on feed properties and production rate. In addition, the work evaluated the effect on production rate of modest increases in melter operating temperature. Glass composition development was based on one of the HLW waste compositions specified by ORP that has a high concentration of aluminum. Small-scale tests were used to provide an initial screening of various glass formulations with respect to melt rates; more definitive screening was provided by the subsequent DM100 tests. Glass properties evaluated included: viscosity, electrical conductivity, crystallinity, gross glass phase separation and the 7- day Product Consistency Test (ASTM-1285). Glass property limits were based upon the reference properties for the WTP HLW melter. However, the WTP crystallinity limit (< 1 vol% at 950oC) was relaxed slightly as a waste loading constraint for the crucible melts.« less

Options for the Separation and Immobilization of Technetium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serne, R Jeffrey; Crum, Jarrod V.; Riley, Brian J.

Among radioactive constituents present in the Hanford tank waste, technetium-99 (Tc) presents a unique challenge in that it is significantly radiotoxic, exists predominantly in the liquid low-activity waste (LAW), and has proven difficult to effectively stabilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant, the LAW fraction will be converted to a glass waste form in the LAW vitrification facility, but a significant fraction of Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment system. This necessitates recycle of the off-gas condensate solution to the LAW glassmore » melter feed. The recycle process is effective in increasing the loading of Tc in the immobilized LAW (ILAW), but it also disproportionately increases the sulfur and halides in the LAW melter feed, which have limited solubility in the LAW glass and thus significantly reduce the amount of LAW (glass waste loading) that can be vitrified and still maintain good waste form properties. This increases both the amount of LAW glass and either the duration of the LAW vitrification mission or requires the need for supplemental LAW treatment capacity. Several options are being considered to address this issue. Two approaches attempt to minimize the off-gas recycle by removing Tc at one of several possible points within the tank waste processing flowsheet. The separated Tc from these two approaches must then be dispositioned in a manner such that the Tc can be safely disposed. Alternative waste forms that do not have the Tc volatility issues associated with the vitrification process are being sought for immobilization of Tc for subsequent storage and disposal. The first objective of this report is to provide insights into the compositions and volumes of the Tc-bearing waste streams including the ion exchange eluate from processing LAW and the off-gas condensate from the melter. The first step to be assessed will be the processing of ion exchange eluate. The second objective of this report is to assess the compatibility of the available waste forms with the anticipated waste streams. Two major categories of Tc-specific waste forms are considered in this report including mineral and metal waste forms. Overall, it is concluded that a metal alloy waste form is the most promising and mature Tc-specific waste form and offers several benefits. One obvious advantage of the disposition of Tc in the metal alloy waste form is the significant reduction of the generated waste form volume, which leads to a reduction of the required storage facility footprint. Among mineral waste forms, glass-bonded sodalite and possibly goethite should also be considered for the immobilization of Tc.« less

Effet de la poudre de verre sur le fluage du C-S-H

NASA Astrophysics Data System (ADS)

Danilova, Maryna

Glass is a unique inert material that could be recycled many times without changing its physical and chemical properties. Nevertheless, for some reason, large quantities of glass are still not recycled and therefore are stored as a waste. Its alternative recycling has become, since long, a major environmental problem. Moreover, glass is a potentially useful material for the development of ecological concrete, consequently, this way valorization seems to be imminent. In this research, characterization of the creep of concrete incorporating waste glass in powder form, i.e. glass powder (GP) as a supplementary cementitious material (GP-concrete) was carried out at a macro- and nanolevels. First, results from experimental study on the under load behaviour of GP-concrete are presented. Different types of strain occurring under load or after unload were discussed: quasi-instantaneous deformation, total mechanical deformation due to the maintained uniaxial compressive load during 1 year, total creep, basic creep, elastic recovery and total recovery. Shrinkage under drying conditions and endogenous shrinkage were also studied. After 1 year creep, the effects of constant load and drying on residual strength were also examined. A comparison was made concerning the final state of the porosity. Afterwards, the thesis reveals the results of tests conducted on the cement paste, going down to its composition and properties of the hydrated phases, in particular of calcium silicate hydrates (C-S-H). All of this, in order to conclude on the harmlessness use of GP regarding to the creep. Keywords : Glass powder, Air-entrained concrete, Creep, Shrinkage, C-S-H, Nanoindentation

Enhanced LAW Glass Correlation - Phase 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muller, Isabelle S.; Matlack, Keith S.; Pegg, Ian L.

About 50 million gallons of high-level mixed waste is currently stored in underground tanks at the United States Department of Energy’s (DOE’s) Hanford site in the State of Washington. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) will provide DOE’s Office of River Protection (ORP) with a means of treating this waste by vitrification for subsequent disposal. The tank waste will be separated into low- and high-activity waste fractions, which will then be vitrified respectively into Immobilized Low Activity Waste (ILAW) and Immobilized High Level Waste (IHLW) products. The ILAW product will be disposed in an engineered facility onmore » the Hanford site while the IHLW product is designed for acceptance into a national deep geological disposal facility for high-level nuclear waste. The ILAW and IHLW products must meet a variety of requirements with respect to protection of the environment before they can be accepted for disposal. Acceptable glass formulations for vitrification of Hanford low activity waste (LAW) must meet a variety of product quality, processability, and waste loading requirements. To this end, The Vitreous State Laboratory (VSL) at The Catholic University of America (CUA) developed and tested a number of glass formulations during Part A, Part B1 and Part B2 of the WTP development program. The testing resulted in the selection of target glass compositions for the processing of eight of the Phase I LAW tanks. The selected glass compositions were tested at the crucible scale to confirm their compliance with ILAW performance requirements. Duramelter 100 (DM100) and LAW Pilot Melter tests were then conducted to demonstrate the viability of these glass compositions for LAW vitrification at high processing rates.« less

Final Report - Crystal Settling, Redox, and High Temperature Properties of ORP HLW and LAW Glasses, VSL-09R1510-1, Rev. 0, dated 6/18/09

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Wang, C.; Gan, H.

2013-11-13

The radioactive tank waste treatment programs at the U. S. Department of Energy (DOE) have featured joule heated ceramic melter technology for the vitrification of high level waste (HLW). The Hanford Tank Waste Treatment and Immobilization Plant (WTP) employs this same basic technology not only for the vitrification of HLW streams but also for the vitrification of Low Activity Waste (LAW) streams. Because of the much greater throughput rates required of the WTP as compared to the vitrification facilities at the West Valley Demonstration Project (WVDP) or the Defense Waste Processing Facility (DWPF), the WTP employs advanced joule heated meltersmore » with forced mixing of the glass pool (bubblers) to improve heat and mass transport and increase melting rates. However, for both HLW and LAW treatment, the ability to increase waste loadings offers the potential to significantly reduce the amount of glass that must be produced and disposed and, therefore, the overall project costs. This report presents the results from a study to investigate several glass property issues related to WTP HLW and LAW vitrification: crystal formation and settling in selected HLW glasses; redox behavior of vanadium and chromium in selected LAW glasses; and key high temperature thermal properties of representative HLW and LAW glasses. The work was conducted according to Test Plans that were prepared for the HLW and LAW scope, respectively. One part of this work thus addresses some of the possible detrimental effects due to considerably higher crystal content in waste glass melts and, in particular, the impact of high crystal contents on the flow property of the glass melt and the settling rate of representative crystalline phases in an environment similar to that of an idling glass melter. Characterization of vanadium redox shifts in representative WTP LAW glasses is the second focal point of this work. The third part of this work focused on key high temperature thermal properties of representative WTP HLW and LAW glasses over a wide range of temperatures, from the melter operating temperature to the glass transition.« less

The formation of crystals in glasses containing rare earth oxides

NASA Astrophysics Data System (ADS)

Fadzil, Syazwani Mohd; Hrma, Pavel; Crum, Jarrod; Siong, Khoo Kok; Ngatiman, Mohammad Fadzlee; Said, Riduan Mt

2014-02-01

Korean spent nuclear fuel will reach the capacity of the available temporary storage by 2016. Pyroprocessing and direct disposal seems to be an alternative way to manage and reuse spent nuclear fuel while avoiding the wet reprocessing technology. Pyroprocessing produces several wastes streams, including metals, salts, and rare earths, which must be converted into stabilized form. A suitable form for rare earth immobilization is borosilicate glass. The borosilicate glass form exhibits excellent durability, allows a high waste loading, and is easy to process. In this work, we combined the rare earths waste of composition (in wt%) 39.2Nd2O3-22.7CeO2-11.7La2O3-10.9PrO2-1.3Eu2O3-1.3Gd2O3-8.1Sm2O3-4.8Y2O3 with a baseline glass of composition 60.2SiO2-16.0B2O3-12.6Na2O-3.8Al2O3-5.7CaO-1.7ZrO2. Crystallization in waste glasses occurs as the waste loading increases. It may produce complicate glass processing and affect the product quality. To study crystal formation, we initially made glasses containing 5%, 10% and 15% of La2O3 and then glasses with 5%, 10% and 15% of the complete rare earth mix. Samples were heat-treated for 24 hours at temperatures 800°C to 1150°C in 50°C increments. Quenched samples were analyzed using an optical microscope, scanning electron microscope with energy dispersive spectroscopy, and x-ray diffraction. Stillwellite (LaBSiO5) and oxyapatite (Ca2La8Si6O26) were found in glasses containing La2O3, while oxyapatite (Ca2La8Si6O26 and NaNd9Si6O26) precipitated in glasses with additions of mixed rare earths. The liquidus temperature (TL) of the glasses containing 5%, 10% and 15% La2O3 were 800°C, 959°C and 986°C, respectively; while TL was 825°C, 1059°C and 1267°C for glasses with 5%, 10% and 15% addition of mixed rare earth oxides. The component coefficients TB2O3, TSiO2, TCaO, and TRE2O3 were also evaluated using a recently published study.

Glass-bonded iodosodalite waste form for immobilization of 129I

NASA Astrophysics Data System (ADS)

Chong, Saehwa; Peterson, Jacob A.; Riley, Brian J.; Tabada, Diana; Wall, Donald; Corkhill, Claire L.; McCloy, John S.

2018-06-01

Immobilization of radioiodine is an important requirement for current and future nuclear fuel cycles. Iodosodalite [Na8(AlSiO4)6I2] was synthesized hydrothermally from metakaolin, NaI, and NaOH. Dried unwashed sodalite powders were used to synthesize glass-bonded iodosodalite waste forms (glass composite materials) by heating pressed pellets at 650, 750, or 850 °C with two types of sodium borosilicate glass binders. These heat-treated specimens were characterized with X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, thermal analysis, porosity and density measurements, neutron activation analysis, and inductively-coupled plasma mass spectrometry. For the best waste form produced (pellets mixed with 10 mass% of glass binder and heat-treated at 750 °C), the maximum possible elemental iodine loading was 19.8 mass%, but only ∼8-9 mass% waste loading of iodine was retained in the waste form after thermal processing. Other pellets with higher iodine retention either contained higher porosity or were incompletely sintered. ASTM C1308 and C1285 (product consistency test, PCT) experiments were performed to understand chemical durability under diffusive and static conditions. The C1308 test resulted in significantly higher normalized loss compared to the C1285 test, most likely because of the strong effect of neutral pH solution renewal and prevention of ion saturation in solution. Both experiments indicated that release rates of Na and Si were higher than for Al and I, probably due to a poorly durable Na-Si-O phase from the glass bonding matrix or from initial sodalite synthesis; however the C1308 test result indicated that congruent dissolution of iodosodalite occurred. The average release rates of iodine obtained from C1308 were 0.17 and 1.29 g m-2 d-1 for 80 or 8 m-1, respectively, and the C1285 analysis gave a value of 2 × 10-5 g m-2 d-1, which is comparable to or better than the durability of other iodine waste forms.

Development, characterization and dissolution behavior of calcium-aluminoborate glass wasteforms to immobilize rare-earth oxides.

PubMed

Kim, Miae; Corkhill, Claire L; Hyatt, Neil C; Heo, Jong

2018-03-28

Calcium-aluminoborate (CAB) glasses were developed to sequester new waste compositions made of several rare-earth oxides generated from the pyrochemical reprocessing of spent nuclear fuel. Several important wasteform properties such as waste loading, processability and chemical durability were evaluated. The maximum waste loading of the CAB compositions was determined to be ~56.8 wt%. Viscosity and the electrical conductivity of the CAB melt at 1300 °C were 7.817 Pa·s and 0.4603 S/cm, respectively, which satisfies the conditions for commercial cold-crucible induction melting (CCIM) process. Addition of rare-earth oxides to CAB glasses resulted in dramatic decreases in the elemental releases of B and Ca in aqueous dissolution experiments. Normalized elemental releases from product consistency standard chemical durability test were <3.62·10 -5  g·m -2 for Nd, 0.009 g·m -2 for Al, 0.067 g·m -2 for B and 0.073 g·m -2 for Ca (at 90, after 7 days, for SA/V = 2000m -1 ); all meet European and US regulation limits. After 20 d of dissolution, a hydrated alteration layer of ~ 200-nm-thick, Ca-depleted and Nd-rich, was formed at the surface of CAB glasses with 20 mol% Nd 2 O 3 whereas boehmite [AlO(OH)] secondary crystalline phases were formed in pure CAB glass that contained no Nd 2 O 3 .

Redox-dependent solubility of technetium in low activity waste glass

NASA Astrophysics Data System (ADS)

Soderquist, Chuck Z.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; McCloy, John S.

2014-06-01

The solubility of technetium was measured in a Hanford low activity waste (LAW) glass simulant, to investigate the extent that technetium solubility controls the incorporation of technetium into LAW glass. A series of LAW glass samples, spiked with 500-6000 ppm of Tc as potassium pertechnetate, were melted at 1000 °C in sealed fused quartz ampoules. Technetium solubility was determined in the quenched bulk glass to be 2000-2800 ppm, with slightly reducing conditions due to choice of milling media resulting in reductant contamination and higher solubility. The chemical form of technetium obtained by X-ray absorption near edge spectroscopy is mainly isolated, octahedrally-coordinated Tc(IV), with a minority of Tc(VII) in some glasses and TcO2 in two glasses. The concentration and speciation of technetium depends on glass redox and amount of technetium added. Salts formed at the top of higher technetium loaded glasses during the melt. The results of this study show that technetium solubility should not be a factor in technetium retention during melting of Hanford LAW glass.

Equilibrium Temperature Profiles within Fission Product Waste Forms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaminski, Michael D.

2016-10-01

We studied waste form strategies for advanced fuel cycle schemes. Several options were considered for three waste streams with the following fission products: cesium and strontium, transition metals, and lanthanides. These three waste streams may be combined or disposed separately. The decay of several isotopes will generate heat that must be accommodated by the waste form, and this heat will affect the waste loadings. To help make an informed decision on the best option, we present computational data on the equilibrium temperature of glass waste forms containing a combination of these three streams.

Optical Basicity and Nepheline Crystallization in High Alumina Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodriguez, Carmen P.; McCloy, John S.; Schweiger, M. J.

2011-02-25

The purpose of this study was to find compositions that increase waste loading of high-alumina wastes beyond what is currently acceptable while avoiding crystallization of nepheline (NaAlSiO4) on slow cooling. Nepheline crystallization has been shown to have a large impact on the chemical durability of high-level waste glasses. It was hypothesized that there would be some composition regions where high-alumina would not result in nepheline crystal production, compositions not currently allowed by the nepheline discriminator. Optical basicity (OB) and the nepheline discriminator (ND) are two ways of describing a given complex glass composition. This report presents the theoretical and experimentalmore » basis for these models. They are being studied together in a quadrant system as metrics to explore nepheline crystallization and chemical durability as a function of waste glass composition. These metrics were calculated for glasses with existing data and also for theoretical glasses to explore nepheline formation in Quadrant IV (passes OB metric but fails ND metric), where glasses are presumed to have good chemical durability. Several of these compositions were chosen, and glasses were made to fill poorly represented regions in Quadrant IV. To evaluate nepheline formation and chemical durability of these glasses, quantitative X-ray diffraction (XRD) analysis and the Product Consistency Test were conducted. A large amount of quantitative XRD data is collected here, both from new glasses and from glasses of previous studies that had not previously performed quantitative XRD on the phase assemblage. Appendix A critically discusses a large dataset to be considered for future quantitative studies on nepheline formation in glass. Appendix B provides a theoretical justification for choice of the oxide coefficients used to compute the OB criterion for nepheline formation.« less

Candidate Low-Temperature Glass Waste Forms for Technetium-99 Recovered from Hanford Effluent Management Facility Evaporator Concentrate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, Mei; Tang, Ming; Rim, Jung Ho

Alternative treatment and disposition options may exist for technetium-99 (99Tc) in secondary liquid waste from the Hanford Direct-Feed Low-Activity Waste (DFLAW) process. One approach includes development of an alternate glass waste form that is suitable for on-site disposition of technetium, including salts and other species recovered by ion exchange or precipitation from the EMF evaporator concentrate. By recovering the Tc content from the stream, and not recycling the treated concentrate, the DFLAW process can potentially be operated in a more efficient manner that lowers the cost to the Department of Energy. This report provides a survey of candidate glass formulationsmore » and glass-making processes that can potentially incorporate technetium at temperatures <700 °C to avoid volatilization. Three candidate technetium feed streams are considered: (1) dilute sodium pertechnetate loaded on a non-elutable ion exchange resin; (2) dilute sodium-bearing aqueous eluent from ion exchange recovery of pertechnetate, or (3) technetium(IV) oxide precipitate containing Sn and Cr solids in an aqueous slurry. From the technical literature, promising candidate glasses are identified based on their processing temperatures and chemical durability data. The suitability and technical risk of three low-temperature glass processing routes (vitrification, encapsulation by sintering into a glass composite material, and sol-gel chemical condensation) for the three waste streams was assessed, based on available low-temperature glass data. For a subset of candidate glasses, their long-term thermodynamic behavior with exposure to water and oxygen was modeled using Geochemist’s Workbench, with and without addition of reducing stannous ion. For further evaluation and development, encapsulation of precipitated TcO2/Sn/Cr in a glass composite material based on lead-free sealing glasses is recommended as a high priority. Vitrification of pertechnetate in aqueous anion exchange eluent solution using a high lead content borate glass, or other low melting glass is also recommended for further evaluation and development. Additional laboratory studies of phase behavior and chemical durability of low-temperature glasses is also recommended to provide risk mitigation if one of the primary development paths proves infeasible. This report is a deliverable for the task “Candidate Low-T Glass Waste Forms for EMF Bottoms On-Site Disposition Alternative Option.”« less

Calcium titanium silicate based glass-ceramic for nuclear waste immobilisation

NASA Astrophysics Data System (ADS)

Sharma, K.; Srivastav, A. P.; Goswami, M.; Krishnan, Madangopal

2018-04-01

Titanate based ceramics (synroc) have been studied for immobilisation of nuclear wastes due to their high radiation and thermal stability. The aim of this study is to synthesis glass-ceramic with stable phases from alumino silicate glass composition and study the loading behavior of actinides in glass-ceramics. The effects of CaO and TiO2 addition on phase evolution and structural properties of alumino silicate based glasses with nominal composition x(10CaO-9TiO2)-y(10Na2O-5 Al2O3-56SiO2-10B2O3); where z = x/y = 1.4-1.8 are reported. The glasses are prepared by melt-quench technique and characterized for thermal and structural properties using DTA and Raman Spectroscopy. Glass transition and peak crystallization temperatures decrease with increase of CaO and TiO2 content, which implies the weakening of glass network and increased tendency of glasses towards crystallization. Sphene (CaTiSiO5) and perovskite (CaTiO3) crystalline phases are confirmed from XRD which are well known stable phase for conditioning of actinides. The microsturcture and elemental analysis indicate the presence of actinide in stable crystalline phases.

FY2016 Update on ILAW Glass Testing for Disposal at IDF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, E. E.; Swanberg, D. J.; Muller, Isabelle S.

2017-04-12

This status report provides a FY2016 update on work performed to collect information on the corrosion behavior of LAW glasses to support the IDF PA. In addition to the development of the baseline operating envelope for the WTP, since 2003, VSL has developed a wide range of LAW formulations that achieve considerably higher waste loadings than the WTP baseline formulations.

Crystallization In High Level Waste (HLW) Glass Melters: Operational Experience From The Savannah River Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.

2014-02-27

processing strategy for the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal tolerant high level waste (HLW) glasses targeting higher waste loadings while still meeting process related limits and melter lifetime expectancies. This report provides amore » review of the scaled melter testing that was completed in support of the Defense Waste Processing Facility (DWPF) melter. Testing with scaled melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by K-3 refractory corrosion versus spinels that precipitated from the HLW glass melt pool. This report includes a review of the crystallization observed with the scaled melters and the full scale DWPF melters (DWPF Melter 1 and DWPF Melter 2). Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for WTP. Operation of the first and second (current) DWPF melters has demonstrated that the strategy of using a liquidus temperature predictive model combined with a 100 °C offset from the normal melter operating temperature of 1150 °C (i.e., the predicted liquidus temperature (TL) of the glass must be 1050 °C or less) has been successful in preventing any detrimental accumulation of spinel in the DWPF melt pool, and spinel has not been observed in any of the pour stream glass samples. Spinel was observed at the bottom of DWPF Melter 1 as a result of K-3 refractory corrosion. Issues have occurred with accumulation of spinel in the pour spout during periods of operation at higher waste loadings. Given that both DWPF melters were or have been in operation for greater than 8 years, the service life of the melters has far exceeded design expectations. It is possible that the DWPF liquidus temperature approach is conservative, in that it may be possible to successfully operate the melter with a small degree of allowable crystallization in the glass. This could be a viable approach to increasing waste loading in the glass assuming that the crystals are suspended in the melt and swept out through the riser and pour spout. Additional study is needed, and development work for WTP might be leveraged to support a different operating limit for the DWPF. Several recommendations are made regarding considerations that need to be included as part of the WTP crystal tolerant strategy based on the DWPF development work and operational data reviewed here. These include: Identify and consider the impacts of potential heat sinks in the WTP melter and glass pouring system; Consider the contributions of refractory corrosion products, which may serve to nucleate additional crystals leading to further accumulation; Consider volatilization of components from the melt (e.g., boron, alkali, halides, etc.) and determine their impacts on glass crystallization behavior; Evaluate the impacts of glass REDuction/OXidation (REDOX) conditions and the distribution of temperature within the WTP melt pool and melter pour chamber on crystal accumulation rate; Consider the impact of precipitated crystals on glass viscosity; Consider the impact of an accumulated crystalline layer on thermal convection currents and bubbler effectiveness within the melt pool; Evaluate the impact of spinel accumulation on Joule heating of the WTP melt pool; and Include noble metals in glass melt experiments because of their potential to act as nucleation sites for spinel crystallization.« less

SUMMARY OF FY11 SULFATE RETENTION STUDIES FOR DEFENSE WASTE PROCESSING FACILITY GLASS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Edwards, T.

2012-05-08

This report describes the results of studies related to the incorporation of sulfate in high level waste (HLW) borosilicate glass produced at the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF). A group of simulated HLW glasses produced for earlier sulfate retention studies was selected for full chemical composition measurements to determine whether there is any clear link between composition and sulfate retention over the compositional region evaluated. In addition, the viscosity of several glasses was measured to support future efforts in modeling sulfate solubility as a function of predicted viscosity. The intent of these studies was to developmore » a better understanding of sulfate retention in borosilicate HLW glass to allow for higher loadings of sulfate containing waste. Based on the results of these and other studies, the ability to improve sulfate solubility in DWPF borosilicate glasses lies in reducing the connectivity of the glass network structure. This can be achieved, as an example, by increasing the concentration of alkali species in the glass. However, this must be balanced with other effects of reduced network connectivity, such as reduced viscosity, potentially lower chemical durability, and in the case of higher sodium and aluminum concentrations, the propensity for nepheline crystallization. Future DWPF processing is likely to target higher waste loadings and higher sludge sodium concentrations, meaning that alkali concentrations in the glass will already be relatively high. It is therefore unlikely that there will be the ability to target significantly higher total alkali concentrations in the glass solely to support increased sulfate solubility without the increased alkali concentration causing failure of other Product Composition Control System (PCCS) constraints, such as low viscosity and durability. No individual components were found to provide a significant improvement in sulfate retention (i.e., an increase of the magnitude necessary to have a dramatic impact on blending, washing, or waste loading strategies for DWPF) for the glasses studied here. In general, the concentrations of those species that significantly improve sulfate solubility in a borosilicate glass must be added in relatively large concentrations (e.g., 13 to 38 wt % or more of the frit) in order to have a substantial impact. For DWPF, these concentrations would constitute too large of a portion of the frit to be practical. Therefore, it is unlikely that specific additives may be introduced into the DWPF glass via the frit to significantly improve sulfate solubility. The results presented here continue to show that sulfate solubility or retention is a function of individual glass compositions, rather than a property of a broad glass composition region. It would therefore be inappropriate to set a single sulfate concentration limit for a range of DWPF glass compositions. Sulfate concentration limits should continue to be identified and implemented for each sludge batch. The current PCCS limit is 0.4 wt % SO{sub 4}{sup 2-} in glass, although frit development efforts have led to an increased limit of 0.6 wt % for recent sludge batches. Slightly higher limits (perhaps 0.7-0.8 wt %) may be possible for future sludge batches. An opportunity for allowing a higher sulfate concentration limit at DWPF may lay lie in improving the laboratory experiments used to set this limit. That is, there are several differences between the crucible-scale testing currently used to define a limit for DWPF operation and the actual conditions within the DWPF melter. In particular, no allowance is currently made for sulfur partitioning (volatility versus retention) during melter processing as the sulfate limit is set for a specific sludge batch. A better understanding of the partitioning of sulfur in a bubbled melter operating with a cold cap as well as the impacts of sulfur on the off-gas system may allow a higher sulfate concentration limit to be established for the melter feed. This approach would have to be taken carefully to ensure that a sulfur salt layer is not formed on top of the melt pool while allowing higher sulfur based feeds to be processed through DWPF.« less

The formation of crystals in glasses containing rare earth oxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fadzil, Syazwani Mohd; Hrma, Pavel; Crum, Jarrod

Korean spent nuclear fuel will reach the capacity of the available temporary storage by 2016. Pyroprocessing and direct disposal seems to be an alternative way to manage and reuse spent nuclear fuel while avoiding the wet reprocessing technology. Pyroprocessing produces several wastes streams, including metals, salts, and rare earths, which must be converted into stabilized form. A suitable form for rare earth immobilization is borosilicate glass. The borosilicate glass form exhibits excellent durability, allows a high waste loading, and is easy to process. In this work, we combined the rare earths waste of composition (in wt%) 39.2Nd{sub 2}O{sub 3}–22.7CeO{sub 2}–11.7La{submore » 2}O{sub 3}–10.9PrO{sub 2}–1.3Eu{sub 2}O{sub 3}–1.3Gd{sub 2}O{sub 3}–8.1Sm{sub 2}O{sub 3}–4.8Y{sub 2}O{sub 3} with a baseline glass of composition 60.2SiO{sub 2}–16.0B{sub 2}O{sub 3}–12.6Na{sub 2}O–3.8Al{sub 2}O{sub 3}–5.7CaO–1.7ZrO{sub 2}. Crystallization in waste glasses occurs as the waste loading increases. It may produce complicate glass processing and affect the product quality. To study crystal formation, we initially made glasses containing 5%, 10% and 15% of La{sub 2}O{sub 3} and then glasses with 5%, 10% and 15% of the complete rare earth mix. Samples were heat-treated for 24 hours at temperatures 800°C to 1150°C in 50°C increments. Quenched samples were analyzed using an optical microscope, scanning electron microscope with energy dispersive spectroscopy, and x-ray diffraction. Stillwellite (LaBSiO{sub 5}) and oxyapatite (Ca{sub 2}La{sub 8}Si{sub 6}O{sub 26}) were found in glasses containing La{sub 2}O{sub 3}, while oxyapatite (Ca{sub 2}La{sub 8}Si{sub 6}O{sub 26} and NaNd{sub 9}Si{sub 6}O{sub 26}) precipitated in glasses with additions of mixed rare earths. The liquidus temperature (T{sub L}) of the glasses containing 5%, 10% and 15% La{sub 2}O{sub 3} were 800°C, 959°C and 986°C, respectively; while T{sub L} was 825°C, 1059°C and 1267°C for glasses with 5%, 10% and 15% addition of mixed rare earth oxides. The component coefficients T{sub B2O3}, T{sub SiO2}, T{sub CaO}, and T{sub RE2O3} were also evaluated using a recently published study.« less

An experimental study on Sodalite and SAP matrices for immobilization of spent chloride salt waste

NASA Astrophysics Data System (ADS)

Giacobbo, Francesca; Da Ros, Mirko; Macerata, Elena; Mariani, Mario; Giola, Marco; De Angelis, Giorgio; Capone, Mauro; Fedeli, Carlo

2018-02-01

In the frame of Generation IV reactors a renewed interest in pyro-processing of spent nuclear fuel is underway. Molten chloride salt waste arising from the recovering of uranium and plutonium through pyro-processing is one of the problematic wastes for direct application of vitrification or ceramization. In this work, Sodalite and SAP have been evaluated and compared as potential matrices for confinement of spent chloride salt waste coming from pyro-processing. To this aim Sodalite and SAP were synthesized both in pure form and mixed with different glass matrices, i.e. commercially available glass frit and borosilicate glass. The confining matrices were loaded with mixed chloride salts to study their retention capacities with respect to the elements of interest. The matrices were characterized and leached for contact times up to 150 days at room temperature and at 90 °C. SEM analyses were also performed in order to compare the matrix surface before and after leaching. Leaching results are discussed and compared in terms of normalized releases with similar results reported in literature. According to this comparative study the SAP matrix with glass frit binder resulted in the best matrix among the ones studied, with respect to retention capacities for both matrix and spent fuel elements.

Defense Waste Processing Facility (DWPF) Viscosity Model: Revisions for Processing High TiO 2 Containing Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C. M.; Edwards, T. B.

Radioactive high-level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-composition modelsmore » form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository. The DWPF SPC system is known as the Product Composition Control System (PCCS). The DWPF will soon be receiving wastes from the Salt Waste Processing Facility (SWPF) containing increased concentrations of TiO 2, Na 2O, and Cs 2O . The SWPF is being built to pretreat the high-curie fraction of the salt waste to be removed from the HLW tanks in the F- and H-Area Tank Farms at the SRS. In order to process TiO 2 concentrations >2.0 wt% in the DWPF, new viscosity data were developed over the range of 1.90 to 6.09 wt% TiO 2 and evaluated against the 2005 viscosity model. An alternate viscosity model is also derived for potential future use, should the DWPF ever need to process other titanate-containing ion exchange materials. The ultimate limit on the amount of TiO 2 that can be accommodated from SWPF will be determined by the three PCCS models, the waste composition of a given sludge batch, the waste loading of the sludge batch, and the frit used for vitrification.« less

Toward Understanding the Effect of Low-Activity Waste Glass Composition on Sulfur Solubility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, John D.; Kim, Dong-Sang; Muller, Isabelle S.

The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO3 on a calcined oxide basis). If the amount of sulfur exceeds its tolerance level a molten salt will accumulate and upset melter operations and potentially shorten melter useful life. Therefore relatively conservative limits have been placed on sulfur loading in melter feed which in-turn significantly impacts the amount of glass that will be produced, in particular at the Hanford site. Crucible-scale sulfur solubilitymore » data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO3 in glass based on 312 individual glass compositions. This model was shown to well represent the data, accounting for over 80% of the variation in data and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed based on 19 scaled melter tests. The model is appropriate for control of waste glass processing which includes uncertainty quantification. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li2O > V2O5 ≈ TiO2 < CaO < P2O5 ≈ ZnO. The components that most decrease sulfur solubility are Cl > Cr2O3 > SiO2 ≈ ZrO2 > Al2O3.« less

Thermodynamic and Microstructural Mechanisms in the Corrosion of Advanced Ceramic Tc-bearing Waste Forms and Thermophysical Properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartmann, Thomas

Technetium-99 (Tc, t 1/2 = 2.13x10 5 years) is a challenge from a nuclear waste perspective and is one of the most abundant, long-lived radioisotopes found in used nuclear fuel (UNF). Within the Hanford Tank Waste Treatment and Immobilization Plant, technetium volatilizes at typical glass melting temperature, is captured in the off-gas treatment system and recycled back into the feed to eventually increase Tc-loadings of the glass. The aim of this NEUP project was to provide an alternative strategy to immobilize fission technetium as durable ceramic waste form and also to avoid the accumulation of volatile technetium within the offmore » gas melter system in the course of vitrifying radioactive effluents in a ceramic melter. During this project our major attention was turned to the fabrication of chemical durable mineral phases where technetium is structurally bond entirely as tetravalent cation. These mineral phases will act as the primary waste form with optimal waste loading and superior resistance against leaching and corrosion. We have been very successful in fabricating phase-pure micro-gram amounts of lanthanide-technetium pyrochlores by dry-chemical synthesis. However, upscaling to a gram-size synthesis route using either dry- or wet-chemical processing was not always successful, but progress can be reported on a variety of aspects. During the course of this 5-year NEUP project (including a 2-year no-cost extension) we have significantly enhanced the existing knowledge on the fabrication and properties of ceramic technetium waste forms.« less

Immobilization and bonding scheme of radioactive iodine-129 in silver tellurite glass

NASA Astrophysics Data System (ADS)

Lee, Cheong Won; Pyo, Jae-Young; Park, Hwan-Seo; Yang, Jae Hwan; Heo, Jong

2017-08-01

Silver tellurite glasses with melting temperatures < 700 °C were prepared to immobilize the 129I that normally volatilizes during high-temperature melting. Glasses have densities of 6.31 ± 0.1 g/cm3 and glass transition temperatures of 165 ± 3 °C that provide thermal stability at the disposal site. Iodine waste loading in glasses was as high as 12.64 wt% of all metallic elements and 11.21 wt% including oxygen. Normalized elemental releases obtained from the product consistency test were well below US regulation of 2 g/m2. Iodines are surrounded by four Ag+ ions forming [Ag4I]3+ units that are further connected to tellurite network through bonds with non-bridging oxygens.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, John D.; Kroll, Jared O.; Hrma, Pavel R.

High-alumina high-level waste (HLW) glasses are prone to nepheline (nominally NaAlSiO4) precipitation during canister-centerline cooling (CCC). If sufficient nepheline forms the chemical durability of the glass will be significantly impacted. Overly conservative constraints have been developed and used to avoid the deleterious effects of nepheline formation in U.S. HLW vitrification plants. The constraint used has been shown to significantly limit the loading of waste in glass at Hanford and therefore the cost and schedule of cleanup. A study was performed to develop an improved understanding of the impacts of glass composition on the formation of nepheline during CCC. Four experimentalmore » phases were conducted in which 90 independent glass compositions were fabricated, subjected to simulated CCC heat-treatments, and characterized for crystallinity – 38 of the 90 test glasses formed nepheline. These data were examined separately and combined with 657 glasses previously tested glasses found in literature. The trends showed that in addition to Na2O, Al2O3, and SiO2 components included in previous constraints B2O3, CaO, K2O, and Li2O also significant impacted the propensity for nepheline formation. A pseudo-ternary submixture approach was proposed to identify the glass composition region prone to nepheline precipitation. This pseudo-ternary with axis of SiO2 + 1.70B2O3, Na2O + 0.813Li2O + 0.439K2O + 0.223CaO, and Al2O3 was found to effectively divide typical U.S. HLW glasses that precipitate nepheline during CCC from those that do not. This approach results in a total misclassification rate of 13%, 7% of which are false negatives (those glasses predicted not to form nepheline that actually do for nepheline). When applied to the 90 glasses developed specifically for Hanford high-alumina HLWs, the misclassification rate is 19% (17/90) with 1/38 false negatives. Application of such a constraint is anticipated to increase the loading of Hanford high-alumina HLWs in glass by roughly one third.« less

COMSOL Multiphysics Model for HLW Canister Filling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kesterson, M. R.

2016-04-11

The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. Wastes containing high concentrations of Al 2O 3 and Na 2O can contribute to nepheline (generally NaAlSiO 4) crystallization, which can sharply reduce the chemical durability of high level waste (HLW) glass. Nepheline crystallization canmore » occur during slow cooling of the glass within the stainless steel canister. The purpose of this work was to develop a model that can be used to predict temperatures of the glass in a WTP HLW canister during filling and cooling. The intent of the model is to support scoping work in the laboratory. It is not intended to provide precise predictions of temperature profiles, but rather to provide a simplified representation of glass cooling profiles within a full scale, WTP HLW canister under various glass pouring rates. These data will be used to support laboratory studies for an improved understanding of the mechanisms of nepheline crystallization. The model was created using COMSOL Multiphysics, a commercially available software. The model results were compared to available experimental data, TRR-PLT-080, and were found to yield sufficient results for the scoping nature of the study. The simulated temperatures were within 60 ºC for the centerline, 0.0762m (3 inch) from centerline, and 0.2286m (9 inch) from centerline thermocouples once the thermocouples were covered with glass. The temperature difference between the experimental and simulated values reduced to 40 ºC, 4 hours after the thermocouple was covered, and down to 20 ºC, 6 hours after the thermocouple was covered. This level of precision is considered acceptable for the scoping nature of the model and the subsequent laboratory glass studies Using the model, two additional glass pouring cycles were conducted. Representative thermocouple data were plotted to show the variations between the two cycles. This provides preliminary data that will be used in laboratory experiments to determine the potential for controlling nepheline crystallization in glass by varying the glass pouring conditions.« less

Glass binder development for a glass-bonded sodalite ceramic waste form

NASA Astrophysics Data System (ADS)

Riley, Brian J.; Vienna, John D.; Frank, Steven M.; Kroll, Jared O.; Peterson, Jacob A.; Canfield, Nathan L.; Zhu, Zihua; Zhang, Jiandong; Kruska, Karen; Schreiber, Daniel K.; Crum, Jarrod V.

2017-06-01

This paper discusses work to develop Na2O-B2O3-SiO2 glass binders for immobilizing LiCl-KCl eutectic salt waste in a glass-bonded sodalite waste form following electrochemical reprocessing of used metallic nuclear fuel. Here, five new glasses with ∼20 mass% Na2O were designed to generate waste forms with high sodalite. The glasses were then used to produce ceramic waste forms with a surrogate salt waste. The waste forms made using these new glasses were formulated to generate more sodalite than those made with previous baseline glasses for this type of waste. The coefficients of thermal expansion for the glass phase in the glass-bonded sodalite waste forms made with the new binder glasses were closer to the sodalite phase in the critical temperature region near and below the glass transition temperature than previous binder glasses used. These improvements should result in lower probability of cracking in the full-scale monolithic ceramic waste form, leading to better long-term chemical durability.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peeler, D; Tommy Edwards, T; Kevin Fox, K

The Savannah River National Laboratory (SRNL) has developed, and continues to enhance, its integrated capability to evaluate the impact of proposed sludge preparation plans on the Defense Waste Processing Facility's (DWPF's) operation. One of the components of this integrated capability focuses on frit development which identifies a viable frit or frits for each sludge option being contemplated for DWPF processing. A frit is considered viable if its composition allows for economic fabrication and if, when it is combined with the sludge option under consideration, the DWPF property/composition models (the models of DWPF's Product Composition Control System (PCCS)) indicate that themore » combination has the potential for an operating window (a waste loading (WL) interval over which the sludge/frit glass system satisfies processability and durability constraints) that would allow DWPF to meet its goals for waste loading and canister production. This report documents the results of SRNL's efforts to identify candidate frit compositions and corresponding predicted operating windows (defined in terms of WL intervals) for the February 2007 compositional projection of Sludge Batch 4 (SB4) developed by the Liquid Waste Organization (LWO). The nominal compositional projection was used to assess projected operating windows (in terms of a waste loading interval over which all predicted properties were classified as acceptable) for various frits, evaluate the applicability of the 0.6 wt% SO{sub 4}{sup =} PCCS limit to the glass systems of interest, and determine the impact (or lack thereof) to the previous SB4 variability studies. It should be mentioned that the information from this report will be coupled with assessments of melt rate to recommend a frit for SB4 processing. The results of this paper study suggest that candidate frits are available to process the nominal SB4 composition over attractive waste loadings of interest to DWPF. Specifically, two primary candidate frits for SB4 processing, Frit 510 and Frit 418, have projected operating windows that should allow for successful processing at DWPF. While Frit 418 has been utilized at DWPF, Frit 510 is a higher B{sub 2}O{sub 3} based frit which could lead to improvements in melt rate. These frits provide relatively large operating windows and demonstrate robustness to possible sludge compositional variation while avoiding potential nepheline formation issues. In addition, assessments of SO{sub 4}{sup =} solubility indicate that the 0.6 wt% SO{sub 4}{sup =} limit in PCCS is applicable for the Frit 418 and the Frit 510 based SB4 glass systems.« less

Toward understanding the effect of low-activity waste glass composition on sulfur solubility

DOE PAGES

Vienna, John D.; Kim, Dong -Sang; Muller, Isabelle S.; ...

2014-07-24

The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO 3 on a calcined oxide basis) depending on the composition of the melter feed and processing conditions. If the amount of sulfur exceeds the melt tolerance level, a molten salt will accumulate, which may upset melter operations and potentially shorten the useful life of the melter. At the Hanford site, relatively conservative limits have been placed on sulfur loading in melter feed, whichmore » in turn significantly increases the amount of glass that will be produced. Crucible-scale sulfur solubility data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO 3 in glass based on 252 simulated Hanford low-activity waste (LAW) glass compositions. This model represents the data well, accounting for over 85% of the variation in data, and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed for 13 scaled melter tests of simulated LAW glasses. The model can be used to help estimate glass volumes and make informed decisions on process options. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li 2O > V 2O 5> CaO ≈ P 2O 5 > Na 2O ≈ B 2O 3 > K 2O. The components that most decrease sulfur solubility are Cl > Cr 2O 3 > Al 2O 3 > ZrO 2 ≈ SnO 2 > Others ≈ SiO 2. As a result, the order of component effects is similar to previous literature data, in most cases.« less

Glass binder development for a glass-bonded sodalite ceramic waste form

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Vienna, John D.; Frank, Steven M.

This paper discusses work to develop Na 2O-B 2O 3-SiO 2 glass binders for immobilizing LiCl-KCl eutectic salt waste in a glass-bonded sodalite waste form following electrochemical reprocessing of used metallic nuclear fuel. In this paper, five new glasses with ~20 mass% Na 2O were designed to generate waste forms with high sodalite. The glasses were then used to produce ceramic waste forms with a surrogate salt waste. The waste forms made using these new glasses were formulated to generate more sodalite than those made with previous baseline glasses for this type of waste. The coefficients of thermal expansion formore » the glass phase in the glass-bonded sodalite waste forms made with the new binder glasses were closer to the sodalite phase in the critical temperature region near and below the glass transition temperature than previous binder glasses used. Finally, these improvements should result in lower probability of cracking in the full-scale monolithic ceramic waste form, leading to better long-term chemical durability.« less

Glass binder development for a glass-bonded sodalite ceramic waste form

DOE PAGES

Riley, Brian J.; Vienna, John D.; Frank, Steven M.; ...

2017-06-01

This paper discusses work to develop Na 2O-B 2O 3-SiO 2 glass binders for immobilizing LiCl-KCl eutectic salt waste in a glass-bonded sodalite waste form following electrochemical reprocessing of used metallic nuclear fuel. In this paper, five new glasses with ~20 mass% Na 2O were designed to generate waste forms with high sodalite. The glasses were then used to produce ceramic waste forms with a surrogate salt waste. The waste forms made using these new glasses were formulated to generate more sodalite than those made with previous baseline glasses for this type of waste. The coefficients of thermal expansion formore » the glass phase in the glass-bonded sodalite waste forms made with the new binder glasses were closer to the sodalite phase in the critical temperature region near and below the glass transition temperature than previous binder glasses used. Finally, these improvements should result in lower probability of cracking in the full-scale monolithic ceramic waste form, leading to better long-term chemical durability.« less

Iodosodalite Waste Forms from Low-Temperature Aqueous Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nam, Junghune; Chong, Saehwa; Riley, Brian J.

ABSTRACT Nuclear energy is one option to meet rising electricity demands, although one concern of this technology is the proper capture and storage of radioisotopes produced during fission processes. One of the more difficult radioisotopes is 129I due to its volatility and poor solubility in traditional waste forms such as borosilicate glass. Iodosodalite has been previously proposed as a viable candidate to immobilize iodine due to high iodine loading and good chemical durability. Iodosodalite was traditionally synthesized using solid state and hydrothermal techniques, but this paper discusses an aqueous synthesis approach to optimize and maximize the iodosodalite yield. Products weremore » pressed into pellets and fired with glass binders. Chemical durability and iodine retention results are included.« less

Experimental Design for Hanford Low-Activity Waste Glasses with High Waste Loading

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piepel, Gregory F.; Cooley, Scott K.; Vienna, John D.

This report discusses the development of an experimental design for the initial phase of the Hanford low-activity waste (LAW) enhanced glass study. This report is based on a manuscript written for an applied statistics journal. Appendices A, B, and E include additional information relevant to the LAW enhanced glass experimental design that is not included in the journal manuscript. The glass composition experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC involving 15 LAW glass components. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directlymore » applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this report. One of the glass components, SO 3, has a solubility limit in glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO 3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO 3 solubility limit had previously been modeled by a partial quadratic mixture model expressed in the relative proportions of the 14 other components. The partial quadratic mixture model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This report describes how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study. A layered design consists of points on an outer layer, and inner layer, and a center point. There were 18 outer-layer glasses chosen using optimal experimental design software to augment 147 existing glass compositions that were within the LAW glass composition experimental region. Then 13 inner-layer glasses were chosen with the software to augment the existing and outer-layer glasses. The experimental design was completed by a center-point glass, a Vitreous State Laboratory glass, and replicates of the center point and Vitreous State Laboratory glasses.« less

Impacts of Process and Prediction Uncertainties on Projected Hanford Waste Glass Amount

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gervasio, Vivianaluxa; Vienna, John D.; Kim, Dong-Sang

Analyses were performed to evaluate the impacts of using the advanced glass models, constraints (Vienna et al. 2016), and uncertainty descriptions on projected Hanford glass mass. The maximum allowable WOL was estimated for waste compositions while simultaneously satisfying all applicable glass property and composition constraints with sufficient confidence. Different components of prediction and composition/process uncertainties were systematically included in the calculations to evaluate their impacts on glass mass. The analyses estimated the production of 23,360 MT of IHLW glass when no uncertainties were taken into accound. Accounting for prediction and composition/process uncertainties resulted in 5.01 relative percent increase in estimatedmore » glass mass 24,531 MT. Roughly equal impacts were found for prediction uncertainties (2.58 RPD) and composition/process uncertainties (2.43 RPD). ILAW mass was predicted to be 282,350 MT without uncertainty and with weaste loading “line” rules in place. Accounting for prediction and composition/process uncertainties resulted in only 0.08 relative percent increase in estimated glass mass of 282,562 MTG. Without application of line rules the glass mass decreases by 10.6 relative percent (252,490 MT) for the case with no uncertainties. Addition of prediction uncertainties increases glass mass by 1.32 relative percent and the addition of composition/process uncertainties increase glass mass by an additional 7.73 relative percent (9.06 relative percent increase combined). The glass mass estimate without line rules (275,359 MT) was 2.55 relative percent lower than that with the line rules (282,562 MT), after accounting for all applicable uncertainties.« less

Tc removal from the waste treatment and immobilization plant low-activity waste vitrification off-gas recycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Nash, Charles A.

Vitrification of Low Activity Waste in the Hanford Waste Treatment and Immobilization Plant generates a condensate stream from the off-gas processes. Components in this stream are partially volatile and accumulate to high concentrations through recycling, which impacts the waste glass loading and facility throughput. The primary radionuclide that vaporizes and accumulates in the stream is 99Tc. This program is investigating Tc removal via reductive precipitation with stannous chloride to examine the potential for diverting this stream to an alternate disposition path. As a result, research has shown stannous chloride to be effective, and this paper describes results of recent experimentsmore » performed to further mature the technology.« less

Tc removal from the waste treatment and immobilization plant low-activity waste vitrification off-gas recycle

DOE PAGES

Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Nash, Charles A.

2017-03-16

Vitrification of Low Activity Waste in the Hanford Waste Treatment and Immobilization Plant generates a condensate stream from the off-gas processes. Components in this stream are partially volatile and accumulate to high concentrations through recycling, which impacts the waste glass loading and facility throughput. The primary radionuclide that vaporizes and accumulates in the stream is 99Tc. This program is investigating Tc removal via reductive precipitation with stannous chloride to examine the potential for diverting this stream to an alternate disposition path. As a result, research has shown stannous chloride to be effective, and this paper describes results of recent experimentsmore » performed to further mature the technology.« less

Glass Property Data and Models for Estimating High-Level Waste Glass Volume

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang

2009-10-05

This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition modelsmore » were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.« less

White paper updating conclusions of 1998 ILAW performance assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

MANN, F.M.

The purpose of this document is to provide a comparison of the estimated immobilized low-activity waste (LAW) disposal system performance against established performance objectives using the beat estimates for parameters and models to describe the system. The principal advances in knowledge since the last performance assessment (known as the 1998 ILAW PA [Mann 1998a]) have been in site specific information and data on the waste form performance for BNFL, Inc. relevant glass formulations. The white paper also estimates the maximum release rates for technetium and other key radionuclides and chemicals from the waste form. Finally, this white paper provides limitedmore » information on the impact of changes in waste form loading.« less

Natural analogues of nuclear waste glass corrosion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

1999-01-06

This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information availablemore » on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peeler, D.; Edwards, T.

High-level waste (HLW) throughput (i.e., the amount of waste processed per unit of time) is primarily a function of two critical parameters: waste loading (WL) and melt rate. For the Defense Waste Processing Facility (DWPF), increasing HLW throughput would significantly reduce the overall mission life cycle costs for the Department of Energy (DOE). Significant increases in waste throughput have been achieved at DWPF since initial radioactive operations began in 1996. Key technical and operational initiatives that supported increased waste throughput included improvements in facility attainment, the Chemical Processing Cell (CPC) flowsheet, process control models and frit formulations. As a resultmore » of these key initiatives, DWPF increased WLs from a nominal 28% for Sludge Batch 2 (SB2) to {approx}34 to 38% for SB3 through SB6 while maintaining or slightly improving canister fill times. Although considerable improvements in waste throughput have been obtained, future contractual waste loading targets are nominally 40%, while canister production rates are also expected to increase (to a rate of 325 to 400 canisters per year). Although implementation of bubblers have made a positive impact on increasing melt rate for recent sludge batches targeting WLs in the mid30s, higher WLs will ultimately make the feeds to DWPF more challenging to process. Savannah River Remediation (SRR) recently requested the Savannah River National Laboratory (SRNL) to perform a paper study assessment using future sludge projections to evaluate whether the current Process Composition Control System (PCCS) algorithms would provide projected operating windows to allow future contractual WL targets to be met. More specifically, the objective of this study was to evaluate future sludge batch projections (based on Revision 16 of the HLW Systems Plan) with respect to projected operating windows using current PCCS models and associated constraints. Based on the assessments, the waste loading interval over which a glass system (i.e., a projected sludge composition with a candidate frit) is predicted to be acceptable can be defined (i.e., the projected operating window) which will provide insight into the ability to meet future contractual WL obligations. In this study, future contractual WL obligations are assumed to be 40%, which is the goal after all flowsheet enhancements have been implemented to support DWPF operations. For a system to be considered acceptable, candidate frits must be identified that provide access to at least 40% WL while accounting for potential variation in the sludge resulting from differences in batch-to-batch transfers into the Sludge Receipt and Adjustment Tank (SRAT) and/or analytical uncertainties. In more general terms, this study will assess whether or not the current glass formulation strategy (based on the use of the Nominal and Variation Stage assessments) and current PCCS models will allow access to compositional regions required to targeted higher WLs for future operations. Some of the key questions to be considered in this study include: (1) If higher WLs are attainable with current process control models, are the models valid in these compositional regions? If the higher WL glass regions are outside current model development or validation ranges, is there existing data that could be used to demonstrate model applicability (or lack thereof)? If not, experimental data may be required to revise current models or serve as validation data with the existing models. (2) Are there compositional trends in frit space that are required by the PCCS models to obtain access to these higher WLs? If so, are there potential issues with the compositions of the associated frits (e.g., limitations on the B{sub 2}O{sub 3} and/or Li{sub 2}O concentrations) as they are compared to model development/validation ranges or to the term 'borosilicate' glass? If limitations on the frit compositional range are realized, what is the impact of these restrictions on other glass properties such as the ability to suppress nepheline formation or influence melt rate? The model based assessments being performed make the assumption that the process control models are applicable over the glass compositional regions being evaluated. Although the glass compositional region of interest is ultimately defined by the specific frit, sludge, and WL interval used, there is no prescreening of these compositional regions with respect to the model development or validation ranges which is consistent with current DWPF operations.« less

Glass binder development for a glass-bonded sodalite ceramic waste form

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Vienna, John D.; Frank, Steven M.

This paper discusses work to develop Na2O-B2O3-SiO2 glass binders for immobilizing LiCl-KCl eutectic salt waste in a glass-bonded sodalite waste form following electrochemical reprocessing of used metallic nuclear fuel. Here, five new glasses with high Na2O contents were designed to generate waste forms having higher sodalite contents and fewer stress fractures. The structural, mechanical, and thermal properties of the new glasses were measured using variety of analytical techniques. The glasses were then used to produce ceramic waste forms with surrogate salt waste. The materials made using the glasses developed during this study were formulated to generate more sodalite than materialsmore » made with previous baseline glasses used. The coefficients of thermal expansion for the glass phase in the glass-bonded sodalite waste forms made with the new binder glasses were closer to the sodalite phase in the critical temperature region near and below the glass transition temperature. These improvements should result in lower probability of cracking in the full-scale monolithic ceramic waste form, leading to better long-term chemical durability. Additionally, a model generated during this study for predicting softening temperature of silicate binder glasses is presented.« less

Cesium titanium silicate and method of making

DOEpatents

Balmer, Mari L.

1997-01-01

The invention is the new material, a ternary compound of cesium, silica, and titania, together with a method of making the ternary compound, cesium titanium silicate pollucite. More specifically, the invention is Cs.sub.2 Ti.sub.2 Si.sub.4 O.sub.13 pollucite which is a new crystalline phase representing a novel class of Ti-containing zeolites. Compositions contain relatively high Cs.sub.2 O and TiO.sub.2 loadings and are durable glass and ceramic materials. The amount of TiO.sub.2 and Cs.sub.2 that can be incorporated into these glasses and crystalline ceramics far exceeds the limits set for the borosilicate high level waste glass.

Cesium titanium silicate and method of making

DOEpatents

Balmer, M.L.

1997-01-07

The invention is the new material, a ternary compound of cesium, silica, and titania, together with a method of making the ternary compound, cesium titanium silicate pollucite. More specifically, the invention is Cs{sub 2}Ti{sub 2}Si{sub 4}O{sub 13} pollucite which is a new crystalline phase representing a novel class of Ti-containing zeolites. Compositions contain relatively high Cs{sub 2}O and TiO{sub 2} loadings and are durable glass and ceramic materials. The amount of TiO{sub 2} and Cs{sub 2} that can be incorporated into these glasses and crystalline ceramics far exceeds the limits set for the borosilicate high level waste glass. 10 figs.

Commercial Ion Exchange Resin Vitrification in Borosilicate Glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cicero-Herman, C.A.; Workman, P.; Poole, K.

1998-05-01

Bench-scale studies were performed to determine the feasibility of vitrification treatment of six resins representative of those used in the commercial nuclear industry. Each resin was successfully immobilized using the same proprietary borosilicate glass formulation. Waste loadings varied from 38 to 70 g of resin/100 g of glass produced depending on the particular resin, with volume reductions of 28 percent to 68 percent. The bench-scale results were used to perform a melter demonstration with one of the resins at the Clemson Environmental Technologies Laboratory (CETL). The resin used was a weakly acidic meth acrylic cation exchange resin. The vitrification processmore » utilized represented a approximately 64 percent volume reduction. Glass characterization, radionuclide retention, offgas analyses, and system compatibility results will be discussed in this paper.« less

Characterization of Mechanical and Bactericidal Properties of Cement Mortars Containing Waste Glass Aggregate and Nanomaterials

PubMed Central

Sikora, Pawel; Augustyniak, Adrian; Cendrowski, Krzysztof; Horszczaruk, Elzbieta; Rucinska, Teresa; Nawrotek, Pawel; Mijowska, Ewa

2016-01-01

The recycling of waste glass is a major problem for municipalities worldwide. The problem concerns especially colored waste glass which, due to its low recycling rate as result of high level of impurity, has mostly been dumped into landfills. In recent years, a new use was found for it: instead of creating waste, it can be recycled as an additive in building materials. The aim of the study was to evaluate the possibility of manufacturing sustainable and self-cleaning cement mortars with use of commercially available nanomaterials and brown soda-lime waste glass. Mechanical and bactericidal properties of cement mortars containing brown soda-lime waste glass and commercially available nanomaterials (amorphous nanosilica and cement containing nanocrystalline titanium dioxide) were analyzed in terms of waste glass content and the effectiveness of nanomaterials. Quartz sand is replaced with brown waste glass at ratios of 25%, 50%, 75% and 100% by weight. Study has shown that waste glass can act as a successful replacement for sand (up to 100%) to produce cement mortars while nanosilica is incorporated. Additionally, a positive effect of waste glass aggregate for bactericidal properties of cement mortars was observed. PMID:28773823

Characterization of Mechanical and Bactericidal Properties of Cement Mortars Containing Waste Glass Aggregate and Nanomaterials.

PubMed

Sikora, Pawel; Augustyniak, Adrian; Cendrowski, Krzysztof; Horszczaruk, Elzbieta; Rucinska, Teresa; Nawrotek, Pawel; Mijowska, Ewa

2016-08-18

The recycling of waste glass is a major problem for municipalities worldwide. The problem concerns especially colored waste glass which, due to its low recycling rate as result of high level of impurity, has mostly been dumped into landfills. In recent years, a new use was found for it: instead of creating waste, it can be recycled as an additive in building materials. The aim of the study was to evaluate the possibility of manufacturing sustainable and self-cleaning cement mortars with use of commercially available nanomaterials and brown soda-lime waste glass. Mechanical and bactericidal properties of cement mortars containing brown soda-lime waste glass and commercially available nanomaterials (amorphous nanosilica and cement containing nanocrystalline titanium dioxide) were analyzed in terms of waste glass content and the effectiveness of nanomaterials. Quartz sand is replaced with brown waste glass at ratios of 25%, 50%, 75% and 100% by weight. Study has shown that waste glass can act as a successful replacement for sand (up to 100%) to produce cement mortars while nanosilica is incorporated. Additionally, a positive effect of waste glass aggregate for bactericidal properties of cement mortars was observed.

XRD, Electron Microscopy and Vibrational Spectroscopy Characterization of Simulated SB6 HLW Glasses - 13028

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stefanovsky, S.V.; Institute of Physical Chemistry and Electrochemistry RAS, Leninskii av. 31, Moscow 119991; Nikonov, B.S.

2013-07-01

Sample glasses have been made using SB6 high level waste (HLW) simulant (high in both Al and Fe) with 12 different frit compositions at a constant waste loading of 36 wt.%. As follows from X-ray diffraction (XRD) and optical and scanning electron microscopy (SEM) data, all the samples are composed of primarily glass and minor concentration of spinel phases which form both isometric grains and fine cubic (∼1 μm) crystals. Infrared spectroscopy (IR) spectra of all the glasses within the range of 400-1600 cm{sup -1} consist of the bands due to stretching and bending modes in silicon-oxygen, boron-oxygen, aluminum-oxygen andmore » iron-oxygen structural groups. Raman spectra showed that for the spectra of all the glasses within the range of 850-1200 cm{sup -1} the best fit is achieved by suggestion of overlapping of three major components with maxima at 911-936 cm{sup -1}, 988-996 cm{sup -1} and 1020-1045 cm{sup -1}. The structural network is primarily composed of metasilicate chains and rings with embedded AlO{sub 4} and FeO{sub 4} tetrahedra. Major BO{sub 4} tetrahedra and BO{sub 3} triangles form complex borate units and are present as separate constituents. (authors)« less

Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blengini, Gian Andrea, E-mail: blengini@polito.it; CNR-IGAG, Institute of Environmental Geology and Geo-Engineering, Corso Duca degli Abruzzi 24, 10129 Turin; Busto, Mirko, E-mail: mirko.busto@polito.it

Highlights: Black-Right-Pointing-Pointer A new eco-efficient recycling route for post-consumer waste glass was implemented. Black-Right-Pointing-Pointer Integrated waste management and industrial production are crucial to green products. Black-Right-Pointing-Pointer Most of the waste glass rejects are sent back to the glass industry. Black-Right-Pointing-Pointer Recovered co-products give more environmental gains than does avoided landfill. Black-Right-Pointing-Pointer Energy intensive recycling must be limited to waste that cannot be closed-loop recycled. - Abstract: As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production.more » Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled.« less

Defense Waste Processing Facility (DWPF) Durability-Composition Models and the Applicability of the Associated Reduction of Constraints (ROC) Criteria for High TiO 2 Containing Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C. M.; Edwards, T. B.; Trivelpiece, C. L.

Radioactive high-level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the DWPF since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it has been poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than relying on statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-composition models formmore » the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to determine, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository. The DWPF SPC system is known as the Product Composition Control System (PCCS). One of the process models within PCCS is known as the Thermodynamic Hydration Energy Reaction MOdel (THERMO™). The DWPF will soon be receiving increased concentrations of TiO 2-, Na 2O-, and Cs 2O-enriched wastes from the Salt Waste Processing Facility (SWPF). The SWPF has been built to pretreat the high-curie fraction of the salt waste to be removed from the HLW tanks in the F- and H-Area Tank Farms at the SRS. In order to validate the existing TiO 2 term in THERMO™ beyond 2.0 wt% in the DWPF, new durability data were developed over the target range of 2.00 to 6.00 wt% TiO 2 and evaluated against the 1995 durability model. The durability was measured by the 7-day Product Consistency Test. This study documents the adequacy of the existing THERMO™ terms. It is recommended that the modified THERMO™ durability models and the modified property acceptable region limits for the durability constraints be incorporated in the next revision of the technical bases for PCCS and then implemented into PCCS. It is also recommended that an reduction of constraints of 4 wt% Al 2O 3 be implemented with no restrictions on the amount of alkali in the glass for TiO 2 values ≥2 wt%. The ultimate limit on the amount of TiO 2 that can be accommodated from SWPF will be determined by the three PCCS models, the waste composition of a given sludge batch, the waste loading of the sludge batch, and the frit used for vitrification.« less

β-Irradiation Effects on the Formation and Stability of CaMoO4 in a Soda Lime Borosilicate Glass Ceramic for Nuclear Waste Storage.

PubMed

Patel, Karishma B; Boizot, Bruno; Facq, Sébastien P; Lampronti, Giulio I; Peuget, Sylvain; Schuller, Sophie; Farnan, Ian

2017-02-06

Molybdenum solubility is a limiting factor to actinide loading in nuclear waste glasses, as it initiates the formation of water-soluble crystalline phases such as alkali molybdates. To increase waste loading efficiency, alternative glass ceramic structures are sought that prove resistant to internal radiation resulting from radioisotope decay. In this study, selective formation of water-durable CaMoO 4 in a soda lime borosilicate is achieved by introducing up to 10 mol % MoO 3 in a 1:1 ratio to CaO using a sintering process. The resulting homogeneously dispersed spherical CaMoO 4 nanocrystallites were analyzed using electron microscopy, X-ray diffraction (XRD), Raman and electron paramagnetic resonance (EPR) spectroscopies prior to and post irradiation, which replicated internal β-irradiation damage on an accelerated scale. Following 0.77 to 1.34 GGy of 2.5 MeV electron radiation CaMoO 4 does not exhibit amorphization or significant transformation. Nor does irradiation induce glass-in-glass phase separation in the surrounding amorphous matrix, or the precipitation of other molybdates, thus proving that excess molybdenum can be successfully incorporated into a structure that it is resistant to β-irradiation proportional to 1000 years of storage without water-soluble byproducts. The CaMoO 4 crystallites do however exhibit a nonlinear Scherrer crystallite size pattern with dose, as determined by a Rietveld refinement of XRD patterns and an alteration in crystal quality as deduced by anisotropic peak changes in both XRD and Raman spectroscopy. Radiation-induced modifications in the CaMoO 4 tetragonal unit cell occurred primarily along the c-axis indicating relaxation of stacked calcium polyhedra. Concurrently, a strong reduction of Mo 6+ to Mo 5+ during irradiation is observed by EPR, which is believed to enhance Ca mobility. These combined results are used to hypothesize a crystallite size alteration model based on a combination of relaxation and diffusion-based processes initiated by added energy from β-impingement and second-order structural modifications induced by defect accumulation.

Recycling of inorganic waste in monolithic and cellular glass-based materials for structural and functional applications.

PubMed

Rincón, Acacio; Marangoni, Mauro; Cetin, Suna; Bernardo, Enrico

2016-07-01

The stabilization of inorganic waste of various nature and origin, in glasses, has been a key strategy for environmental protection for the last decades. When properly formulated, glasses may retain many inorganic contaminants permanently, but it must be acknowledged that some criticism remains, mainly concerning costs and energy use. As a consequence, the sustainability of vitrification largely relies on the conversion of waste glasses into new, usable and marketable glass-based materials, in the form of monolithic and cellular glass-ceramics. The effective conversion in turn depends on the simultaneous control of both starting materials and manufacturing processes. While silica-rich waste favours the obtainment of glass, iron-rich wastes affect the functionalities, influencing the porosity in cellular glass-based materials as well as catalytic, magnetic, optical and electrical properties. Engineered formulations may lead to important reductions of processing times and temperatures, in the transformation of waste-derived glasses into glass-ceramics, or even bring interesting shortcuts. Direct sintering of wastes, combined with recycled glasses, as an example, has been proven as a valid low-cost alternative for glass-ceramic manufacturing, for wastes with limited hazardousness. The present paper is aimed at providing an up-to-date overview of the correlation between formulations, manufacturing technologies and properties of most recent waste-derived, glass-based materials. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Thermodynamic model of natural, medieval and nuclear waste glass durability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C.M.; Plodinec, M.J.

1983-01-01

A thermodynamic model of glass durability based on hydration of structural units has been applied to natural glass, medieval window glasses, and glasses containing nuclear waste. The relative durability predicted from the calculated thermodynamics correlates directly with the experimentally observed release of structural silicon in the leaching solution in short-term laboratory tests. By choosing natural glasses and ancient glasses whose long-term performance is known, and which bracket the durability of waste glasses, the long-term stability of nuclear waste glasses can be interpolated among these materials. The current Savannah River defense waste glass formulation is as durable as natural basalt frommore » the Hanford Reservation (10/sup 6/ years old). The thermodynamic hydration energy is shown to be related to the bond energetics of the glass. 69 references, 2 figures, 1 table.« less

IMPACT OF PARTICLE AGGLOMERATION ON ACCUMULATION RATES IN THE GLASS DISCHARGE RISER OF HLW MELTER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matyas, Josef; Jansik, Danielle P.; Owen, Antionette T.

2013-08-05

The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with X-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, andmore » on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185±155 µm, and produced >3 mm thick layer after 120 h at 850 °C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.« less

Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, A. A.; Rodriguez, C. A.; Matyas, J.

2012-11-12

The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, andmore » on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185+-155 {mu}m, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.« less

Developing Specifications for Waste Glass, Municipal Waste Combustor Ash and Waste Tires as Highway Fill Materials (Continuation): Final Report. Volume 2. Waste Glass.

DOT National Transportation Integrated Search

1995-04-01

A two year study was conducted as a continuation project for the Florida Department of Transportation (FDOT) to evaluate Municipal Waste Combustor (MWD) ash, Waste Glass, and Waste Tires for use as general highway fill. Initial studies conducted at F...

Treatment of halogen-containing waste and other waste materials

DOEpatents

Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

1997-01-01

A process for treating a halogen-containing waste material. The process provides a bath of molten glass containing a sacrificial metal oxide capable of reacting with a halogen in the waste material. The sacrificial metal oxide is present in the molten glass in at least a stoichiometric amount with respect to the halogen in the waste material. The waste material is introduced into the bath of molten glass to cause a reaction between the halogen in the waste material and the sacrificial metal oxide to yield a metal halide. The metal halide is a gas at the temperature of the molten glass. The gaseous metal halide is separated from the molten glass and contacted with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal hydroxide or metal oxide-containing precipitate and a soluble alkali metal halide. The precipitate is then separated from the aqueous scrubber solution. The molten glass containing the treated waste material is removed from the bath as a waste glass. The process of the invention can be used to treat all types of waste material including radioactive wastes. The process is particularly suited for separating halogens from halogen-containing wastes.

Treatment of halogen-containing waste and other waste materials

DOEpatents

Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

1997-03-18

A process is described for treating a halogen-containing waste material. The process provides a bath of molten glass containing a sacrificial metal oxide capable of reacting with a halogen in the waste material. The sacrificial metal oxide is present in the molten glass in at least a stoichiometric amount with respect to the halogen in the waste material. The waste material is introduced into the bath of molten glass to cause a reaction between the halogen in the waste material and the sacrificial metal oxide to yield a metal halide. The metal halide is a gas at the temperature of the molten glass. The gaseous metal halide is separated from the molten glass and contacted with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal hydroxide or metal oxide-containing precipitate and a soluble alkali metal halide. The precipitate is then separated from the aqueous scrubber solution. The molten glass containing the treated waste material is removed from the bath as a waste glass. The process of the invention can be used to treat all types of waste material including radioactive wastes. The process is particularly suited for separating halogens from halogen-containing wastes. 3 figs.

Characteristics of waste automotive glasses as silica resource in ferrosilicon synthesis.

PubMed

Farzana, Rifat; Rajarao, Ravindra; Sahajwalla, Veena

2016-02-01

This fundamental research on end-of-life automotive glasses, which are difficult to recycle, is aimed at understanding the chemical and physical characteristics of waste glasses as a resource of silica to produce ferrosilicon. Laboratory experiments at 1550°C were carried out using different automotive glasses and the results compared with those obtained with pure silica. In situ images of slag-metal separation showed similar behaviour for waste glasses and silica-bearing pellets. Though X-ray diffraction (XRD) showed different slag compositions for glass and silica-bearing pellets, formation of ferrosilicon was confirmed. Synthesized ferrosilicon alloy from waste glasses and silica were compared by Raman, X-ray photoelectron spectroscopy and scanning electron microscopy (SEM) analysis. Silicon concentration in the synthesized alloys showed almost 92% silicon recovery from the silica-bearing pellet and 74-92% silicon recoveries from various waste glass pellets. The polyvinyl butyral (PVB) plastic layer in the windshield glass decomposed at low temperature and did not show any detrimental effect on ferrosilicon synthesis. This innovative approach of using waste automotive glasses as a silica source for ferrosilicon production has the potential to create sustainable pathways, which will reduce specialty glass waste in landfill. © The Author(s) 2015.

Corrosion of inconel in high-temperature borosilicate glass melts containing simulant nuclear waste

NASA Astrophysics Data System (ADS)

Mao, Xianhe; Yuan, Xiaoning; Brigden, Clive T.; Tao, Jun; Hyatt, Neil C.; Miekina, Michal

2017-10-01

The corrosion behaviors of Inconel 601 in the borosilicate glass (MW glass) containing 25 wt.% of simulant Magnox waste, and in ZnO, Mn2O3 and Fe2O3 modified Mg/Ca borosilicate glasses (MZMF and CZMF glasses) containing 15 wt.% of simulant POCO waste, were evaluated by dimensional changes, the formation of internal defects and changes in alloy composition near corrosion surfaces. In all three kinds of glass melts, Cr at the inconel surface forms a protective Cr2O3 scale between the metal surface and the glass, and alumina precipitates penetrate from the metal surface or formed in-situ. The corrosion depths of inconel 601 in MW waste glass melt are greater than those in the other two glass melts. In MW glass, the Cr2O3 layer between inconel and glass is fragmented because of the reaction between MgO and Cr2O3, which forms the crystal phase MgCr2O4. In MZMF and CZMF waste glasses the layers are continuous and a thin (Zn, Fe, Ni, B)-containing layer forms on the surface of the chromium oxide layer and prevents Cr2O3 from reacting with MgO or other constituents. MgCr2O4 was observed in the XRD analysis of the bulk MW waste glass after the corrosion test, and ZrSiO4 in the MZMF waste glass, and ZrSiO4 and CaMoO4 in the CZMF waste glass.

Reuse of ground waste glass as aggregate for mortars.

PubMed

Corinaldesi, V; Gnappi, G; Moriconi, G; Montenero, A

2005-01-01

This work was aimed at studying the possibility of reusing waste glass from crushed containers and building demolition as aggregate for preparing mortars and concrete. At present, this kind of reuse is still not common due to the risk of alkali-silica reaction between the alkalis of cement and silica of the waste glass. This expansive reaction can cause great problems of cracking and, consequently, it can be extremely deleterious for the durability of mortar and concrete. However, data reported in the literature show that if the waste glass is finely ground, under 75mum, this effect does not occur and mortar durability is guaranteed. Therefore, in this work the possible reactivity of waste glass with the cement paste in mortars was verified, by varying the particle size of the finely ground waste glass. No reaction has been detected with particle size up to 100mum thus indicating the feasibility of the waste glass reuse as fine aggregate in mortars and concrete. In addition, waste glass seems to positively contribute to the mortar micro-structural properties resulting in an evident improvement of its mechanical performance.

Use of thin film transistor liquid crystal display (TFT-LCD) waste glass in the production of ceramic tiles.

PubMed

Lin, Kae-Long

2007-09-05

In this study, we employ the following operating conditions: varied pressure (25 kgf/cm(2)), sintering temperature (900-1200 degrees C), sintering time (6h), percentage of thin film transistor liquid crystal display (TFT-LCD) waste glass by weight (0-50%) and temperature rising at a rate of 5 degrees C/min, to fabricate clay tiles. The sintering characteristics of the clay blended with TFT-LCD waste glass tiles are examined to evaluate the feasibility of the reuse of TFT-LCD waste glass. TFT-LCD waste glass contains large amounts of glass. The TCLP leaching concentrations all met the ROC EPAs current regulatory thresholds. The addition of TFT-LCD waste glass to the mixture, increased the apparent weight loss. The incorporation of 50% TFT-LCD waste glass resulted in a significant increase in the porosity ratio of the specimens compared to the porosity ratio of the ceramic tile containing TFT-LCD waste glass. The main constituent in both the clay tile and the clay with TFT-LCD waste glass samples is quartz. Increasing the temperature resulted in an increase in the flexural strength and resistance to abrasion in the tiles. The porosity ratio decreases as shrinkage increases. The relation between the porosity ratio and the hardness of the tiles used in the study is also shown.

WTP Waste Feed Qualification: Glass Fabrication Unit Operation Testing Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, M. E.; Newell, J. D.; Johnson, F. C.

The waste feed qualification program is being developed to protect the Hanford Tank Waste Treatment and Immobilization Plant (WTP) design, safety basis, and technical basis by assuring waste acceptance requirements are met for each staged waste feed campaign prior to transfer from the Tank Operations Contractor to the feed receipt vessels inside the Pretreatment Facility. The Waste Feed Qualification Program Plan describes the three components of waste feed qualification: 1. Demonstrate compliance with the waste acceptance criteria 2. Determine waste processability 3. Test unit operations at laboratory scale. The glass fabrication unit operation is the final step in the processmore » demonstration portion of the waste feed qualification process. This unit operation generally consists of combining each of the waste feed streams (high-level waste (HLW) and low-activity waste (LAW)) with Glass Forming Chemicals (GFCs), fabricating glass coupons, performing chemical composition analysis before and after glass fabrication, measuring hydrogen generation rate either before or after glass former addition, measuring rheological properties before and after glass former addition, and visual observation of the resulting glass coupons. Critical aspects of this unit operation are mixing and sampling of the waste and melter feeds to ensure representative samples are obtained as well as ensuring the fabrication process for the glass coupon is adequate. Testing was performed using a range of simulants (LAW and HLW simulants), and these simulants were mixed with high and low bounding amounts of GFCs to evaluate the mixing, sampling, and glass preparation steps in shielded cells using laboratory techniques. The tests were performed with off-the-shelf equipment at the Savannah River National Laboratory (SRNL) that is similar to equipment used in the SRNL work during qualification of waste feed for the Defense Waste Processing Facility (DWPF) and other waste treatment facilities at the Savannah River Site. It is not expected that the exact equipment used during this testing will be used during the waste feed qualification testing for WTP, but functionally similar equipment will be used such that the techniques demonstrated would be applicable. For example, the mixing apparatus could use any suitable mixer capable of being remoted and achieving similar mixing speeds to those tested.« less

Direction of CRT waste glass processing: electronics recycling industry communication.

PubMed

Mueller, Julia R; Boehm, Michael W; Drummond, Charles

2012-08-01

Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. Copyright © 2012 Elsevier Ltd. All rights reserved.

Use of photovoltaics for waste heat recovery

DOEpatents

Polcyn, Adam D

2013-04-16

A device for recovering waste heat in the form of radiated light, e.g. red visible light and/or infrared light includes a housing having a viewing window, and a photovoltaic cell mounted in the housing in a relationship to the viewing window, wherein rays of radiated light pass through the viewing window and impinge on surface of the photovoltaic cell. The housing and/or the cell are cooled so that the device can be used with a furnace for an industrial process, e.g. mounting the device with a view of the interior of the heating chamber of a glass making furnace. In this manner, the rays of the radiated light generated during the melting of glass batch materials in the heating chamber pass through the viewing window and impinge on the surface of the photovoltaic cells to generate electric current which is passed onto an electric load.

Direction of CRT waste glass processing: Electronics recycling industry communication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller, Julia R., E-mail: mueller.143@osu.edu; Boehm, Michael W.; Drummond, Charles

2012-08-15

Highlights: Black-Right-Pointing-Pointer Given a large flow rate of CRT glass {approx}10% of the panel glass stream will be leaded. Black-Right-Pointing-Pointer The supply of CRT waste glass exceeded demand in 2009. Black-Right-Pointing-Pointer Recyclers should use UV-light to detect lead oxide during the separation process. Black-Right-Pointing-Pointer Recycling market analysis techniques and results are given for CRT glass. Black-Right-Pointing-Pointer Academic initiatives and the necessary expansion of novel product markets are discussed. - Abstract: Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, andmore » the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased.« less

GlassForm

DOE Office of Scientific and Technical Information (OSTI.GOV)

2011-09-16

GlassForm is a software tool for generating preliminary waste glass formulas for a given waste stream. The software is useful because it reduces the number of verification melts required to develop a suitable additive composition. The software includes property models that calculate glass properties of interest from the chemical composition of the waste glass. The software includes property models for glass viscosity, electrical conductivity, glass transition temperature, and leach resistance as measured by the 7-day product consistency test (PCT).

Glass former composition and method for immobilizing nuclear waste using the same

DOEpatents

Cadoff, Laurence H.; Smith-Magowan, David B.

1988-01-01

An alkoxide glass former composition has silica-containing constituents present as solid particulates of a particle size of 0.1 to 0.7 micrometers in diameter in a liquid carrier phase substantially free of dissolved silica. The glass former slurry is resistant to coagulation and may contain other glass former metal constituents. The immobilization of nuclear waste employs the described glass former by heating the same to reduce the volume, mixing the same with the waste, and melting the resultant mixture to encapsulate the waste in the resultant glass.

Elucidating the effects of solar panel waste glass substitution on the physical and mechanical characteristics of clay bricks.

PubMed

Lin, Kae-Long; Huang, Long-Sheng; Shie, Je-Lueng; Cheng, Ching-Jung; Lee, Ching-Hwa; Chang, Tien-Chin

2013-01-01

This study deals with the effect of solar panel waste glass on fired clay bricks. Brick samples were heated to temperatures which varied from 700-1000 degrees C for 6 h, with a heating rate of 10 degrees C min(-1). The material properties of the resultant material were then determined, including speciation variation, loss on ignition, shrinkage, bulk density, 24-h absorption rate, compressive strength and salt crystallization. The results indicate that increasing the amount of solar panel waste glass resulted in a decrease in the water absorption rate and an increase in the compressive strength of the solar panel waste glass bricks. The 24-h absorption rate and compressive strength of the solar panel waste glass brick made from samples containing 30% solar panel waste glass sintered at 1000 degrees C all met the Chinese National Standard (CNS) building requirements for first-class brick (compressive strengths and water absorption of the bricks were 300 kg cm(-2) and 10% of the brick, respectively). The addition of solar panel waste glass to the mixture reduced the degree of firing shrinkage. The salt crystallization test and wet-dry tests showed that the addition of solar panel waste glass had highly beneficial effects in that it increased the durability of the bricks. This indicates that solar panel waste glass is indeed suitable for the partial replacement of clay in bricks.

Eco-efficient waste glass recycling: Integrated waste management and green product development through LCA.

PubMed

Blengini, Gian Andrea; Busto, Mirko; Fantoni, Moris; Fino, Debora

2012-05-01

As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mix proportions and properties of CLSC made from thin film transition liquid crystal display optical waste glass.

PubMed

Wang, Her-Yung; Chen, Jyun-Sheng

2010-01-01

In this study, controlled low-strength concrete (CLSC) is mixed using different water-to-binder (W/B) ratios (1.1, 1.3 and 1.5) and various percentages of sand substituted by waste LCD glass sand (0%, 10%, 20% and 30%). The properties of the fresh concrete, including compressive strength, electrical resistivity, ultrasonic pulse velocity, permeability ratio and shrinking of the CLSC, are examined. Results show that increases in amount of waste glass added result in better slump and slump flow, longer initial setting time and smaller unit weight. Compressive strength decreases with increasing W/B ratio and greater amounts of waste glass added. Both electrical resistivity and ultrasonic pulse velocity increase with increases in amount of waste glass and decreases in W/B ratio. On the contrary, the permeability ratio increases with increases in W/B ratio, but decreases with greater amounts of waste glass added. CLSC specimens cured for different durations show little changes in length with shrinkage below 0.025%. Our findings reveal that CLSC mixed using waste LCD glass in place of sand can meet design requirements. Recycling of waste LCD glass not only offers an economical substitute for aggregates, but also an ecological alternative for waste management. 2009 Elsevier Ltd. All rights reserved.

X-ray absorption and Raman spectroscopy studies of molybdenum environments in borosilicate waste glasses

NASA Astrophysics Data System (ADS)

McKeown, David A.; Gan, Hao; Pegg, Ian L.

2017-05-01

Mo-containing high-level nuclear waste borosilicate glasses were investigated as part of an effort to improve Mo loading while avoiding yellow phase crystallization. Previous work showed that additions of vanadium decrease yellow phase formation and increases Mo solubility. X-ray absorption spectroscopy (XAS) and Raman spectroscopy were used to characterize Mo environments in HLW borosilicate glasses and to investigate possible structural relationships between Mo and V. Mo XAS spectra for the glasses indicate isolated tetrahedral Mo6+O4 with Mo-O distances near 1.75 Å. V XANES indicate tetrahedral V5+O4 as the dominant species. Raman spectra show composition dependent trends, where Mo-O symmetrical stretch mode frequencies (ν1) are sensitive to the mix of alkali and alkaline earth cations, decreasing by up to 10 cm-1 for glasses that change from Li+ to Na+ as the dominant network-modifying species. This indicates that MoO4 tetrahedra are isolated from the borosilicate network and are surrounded, at least partly, by Na+ and Li+. Secondary ν1 frequency effects, with changes up to 7 cm-1, were also observed with increasing V2O5 and MoO3 content. These secondary trends may indicate MoO4-MoO4 and MoO4-VO4 clustering, suggesting that V additions may stabilize Mo in the matrix with respect to yellow phase formation.

Final Report - LAW Envelope C Glass Formulation Testing to Increase Waste Loading, VSL-05R5900-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Pegg, I. L.; Matlack, K. S.

2013-12-03

This report describes the results of testing specified by Test Plan VSL-05R5900-1 Rev.0. The work was performed in compliance with the quality assurance requirements specified in the Test Plan. Results required by the Test Plan are reported. The test results and this report have been reviewed for correctness, technical adequacy, completeness, and accuracy.

Performance Characteristics of Waste Glass Powder Substituting Portland Cement in Mortar Mixtures

NASA Astrophysics Data System (ADS)

Kara, P.; Csetényi, L. J.; Borosnyói, A.

2016-04-01

In the present work, soda-lime glass cullet (flint, amber, green) and special glass cullet (soda-alkaline earth-silicate glass coming from low pressure mercury-discharge lamp cullet and incandescent light bulb borosilicate glass waste cullet) were ground into fine powders in a laboratory planetary ball mill for 30 minutes. CEM I 42.5N Portland cement was applied in mortar mixtures, substituted with waste glass powder at levels of 20% and 30%. Characterisation and testing of waste glass powders included fineness by laser diffraction particle size analysis, specific surface area by nitrogen adsorption technique, particle density by pycnometry and chemical analysis by X-ray fluorescence spectrophotometry. Compressive strength, early age shrinkage cracking and drying shrinkage tests, heat of hydration of mortars, temperature of hydration, X-ray diffraction analysis and volume stability tests were performed to observe the influence of waste glass powder substitution for Portland cement on physical and engineering properties of mortar mixtures.

YIELD STRESS REDUCTION OF DWPF MELTER FEED SLURRIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, M; Michael02 Smith, M

2006-12-28

The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies High Level Waste for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. The HLW consists of insoluble metal hydroxides (primarily iron, aluminum, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, sulfate). The pretreatment process acidifies the sludge with nitric and formic acids, adds the glass formers as glass frit, then concentrates the resulting slurry to approximately 50 weight percent (wt%) total solids. This slurry is fed to the joule-heated melter where the remaining water is evaporated followedmore » by calcination of the solids and conversion to glass. The Savannah River National Laboratory (SRNL) is currently assisting DWPF efforts to increase throughput of the melter. As part of this effort, SRNL has investigated methods to increase the solids content of the melter feed to reduce the heat load required to complete the evaporation of water and allow more of the energy available to calcine and vitrify the waste. The process equipment in the facility is fixed and cannot process materials with high yield stresses, therefore increasing the solids content will require that the yield stress of the melter feed slurries be reduced. Changing the glass former added during pretreatment from an irregularly shaped glass frit to nearly spherical beads was evaluated. The evaluation required a systems approach which included evaluations of the effectiveness of beads in reducing the melter feed yield stress as well as evaluations of the processing impacts of changing the frit morphology. Processing impacts of beads include changing the settling rate of the glass former (which effects mixing and sampling of the melter feed slurry and the frit addition equipment) as well as impacts on the melt behavior due to decreased surface area of the beads versus frit. Beads were produced from the DWPF process frit by fire polishing. The frit was allowed to free fall through a flame, then quenched with a water spray. Approximately 90% of the frit was converted to beads by this process, as shown in Figure 1. Borosilicate beads of various diameters were also procured for initial testing.« less

Method for calcining radioactive wastes

DOEpatents

Bjorklund, William J.; McElroy, Jack L.; Mendel, John E.

1979-01-01

This invention relates to a method for the preparation of radioactive wastes in a low leachability form by calcining the radioactive waste on a fluidized bed of glass frit, removing the calcined waste to melter to form a homogeneous melt of the glass and the calcined waste, and then solidifying the melt to encapsulate the radioactive calcine in a glass matrix.

Glass Development for Treatment of LANL Evaporator Bottoms Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

DE Smith; GF Piepel; GW Veazey

1998-11-20

Vitrification is an attractive treatment option for meeting the stabilization and final disposal requirements of many plutonium (Pu) bearing materials and wastes at the Los Alamos National Laboratory (LANL) TA-55 facility, Rocky Flats Environmental Technology Site (RFETS), Hanford, and other Department of Energy (DOE) sites. The Environmental Protection Agency (EPA) has declared that vitrification is the "best demonstrated available technology" for high- level radioactive wastes (HLW) (Federal Register 1990) and has produced a handbook of vitriilcation technologies for treatment of hazardous and radioactive waste (US EPA, 1992). This technology has been demonstrated to convert Pu-containing materials (Kormanos, 1997) into durablemore » (Lutze, 1988) and accountable (Forsberg, 1995) waste. forms with reduced need for safeguarding (McCulhun, 1996). The composition of the Evaporator Bottoms Waste (EVB) at LANL, like that of many other I%-bearing materials, varies widely and is generally unpredictable. The goal of this study is to optimize the composition of glass for EVB waste at LANL, and present the basic techniques and tools for developing optimized glass compositions for other Pu-bearing materials in the complex. This report outlines an approach for glass formulation with fixed property restrictions, using glass property-composition databases. This approach is applicable to waste glass formulation for many variable waste streams and vitrification technologies.. Also reported are the preliminary property data for simulated evaporator bottom glasses, including glass viscosity and glass leach resistance using the Toxicity Characteristic Leaching Procedure (TCLP).« less

Recycling of glass: accounting of greenhouse gases and global warming contributions.

PubMed

Larsen, Anna W; Merrild, Hanna; Christensen, Thomas H

2009-11-01

Greenhouse gas (GHG) emissions related to recycling of glass waste were assessed from a waste management perspective. Focus was on the material recovery facility (MRF) where the initial sorting of glass waste takes place. The MRF delivers products like cullet and whole bottles to other industries. Two possible uses of reprocessed glass waste were considered: (i) remelting of cullet added to glass production; and (ii) re-use of whole bottles. The GHG emission accounting included indirect upstream emissions (provision of energy, fuels and auxiliaries), direct activities at the MRF and bottle-wash facility (combustion of fuels) as well as indirect downstream activities in terms of using the recovered glass waste in other industries and, thereby, avoiding emissions from conventional production. The GHG accounting was presented as aggregated global warming factors (GWFs) for the direct and indirect upstream and downstream processes, respectively. The range of GWFs was estimated to 0-70 kg CO(2)eq. tonne( -1) of glass waste for the upstream activities and the direct emissions from the waste management system. The GWF for the downstream effect showed some significant variation between the two cases. It was estimated to approximately -500 kg CO(2)-eq. tonne(- 1) of glass waste for the remelting technology and -1500 to -600 kg CO(2)-eq. tonne(-1) of glass waste for bottle re-use. Including the downstream process, large savings of GHG emissions can be attributed to the waste management system. The results showed that, in GHG emission accounting, attention should be drawn to thorough analysis of energy sources, especially electricity, and the downstream savings caused by material substitution.

Thermal Predictions of the Cooling of Waste Glass Canisters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Donna Post Guillen

2014-11-01

Radioactive liquid waste from five decades of weapons production is slated for vitrification at the Hanford site. The waste will be mixed with glass forming additives and heated to a high temperature, then poured into canisters within a pour cave where the glass will cool and solidify into a stable waste form for disposal. Computer simulations were performed to predict the heat rejected from the canisters and the temperatures within the glass during cooling. Four different waste glass compositions with different thermophysical properties were evaluated. Canister centerline temperatures and the total amount of heat transfer from the canisters to themore » surrounding air are reported.« less

Reference commercial high-level waste glass and canister definition

NASA Astrophysics Data System (ADS)

Slate, S. C.; Ross, W. A.; Partain, W. L.

1981-09-01

Technical data and performance characteristics of a high level waste glass and canister intended for use in the design of a complete waste encapsulation package suitable for disposal in a geologic repository are presented. The borosilicate glass contained in the stainless steel canister represents the probable type of high level waste product that is produced in a commercial nuclear-fuel reprocessing plant. Development history is summarized for high level liquid waste compositions, waste glass composition and characteristics, and canister design. The decay histories of the fission products and actinides (plus daughters) calculated by the ORIGEN-II code are presented.

Deployment of Cesium Recovered from High Level Liquid Waste for Irradiation - Indian Scenario - 13128

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vincent, Tessy; Shah, J.G.; Kumar, Amar

2013-07-01

Recovery of Cs-137 from HLW and its utilisation as source pencil in place of Co-60 is vital for medical and sewage treatment applications in India. For separation of Cs, specific ion exchange resins as well as 'Calyx crown' solvent have been developed and synthesized indigenously. A flow sheet involving separation of Cs from acidic HLW using Ammonium Molybdo Phosphate (AMP) resins, recovery of Cs from the loaded AMP column by dissolving it in alkali, ion exchange purification of Cs rich alkaline solution using Resorcinol-Formaldehyde Poly condensate (RF) resins and its elution in cesium nitrate form was developed and demonstrated. Solventmore » extraction route employing 0.03 Molar, 1-3-octyl oxy Calyx (4) arene crown-6 in 30% isodecyl alcohol and dodecane was also established using mixer settlers. Cesium lithium borosilicate glass based formulations have been considered as a glass matrix for Cs irradiation pencils. While choosing this vitreous matrix, attributes addressing maximum possible Cs-137 loading, low glass pouring temperature to minimise Cs volatility, reasonably good mechanical strength and good chemical durability have been considered. Recovered cesium nitrate solution was vitrified along with glass additives in an induction heated metallic melter and subsequently poured into 12 numbers of Cs irradiation pencils positioned on turn-table equipped with the load cell. The complete cycle involving recovery of Cs from HLW followed by its conversion into Cs pencil was demonstrated. (authors)« less

Chemical composition analysis and product consistency tests to support Enhanced Hanford Waste Glass Models. Results for the Augusta and October 2014 LAW Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Edwards, T. B.; Best, D. R.

2015-07-07

In this report, the Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for several simulated low activity waste (LAW) glasses (designated as the August and October 2014 LAW glasses) fabricated by the Pacific Northwest National Laboratory. The results of these analyses will be used as part of efforts to revise or extend the validation regions of the current Hanford Waste Treatment and Immobilization Plant glass property models to cover a broader span of waste compositions.

High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunnane, J.C.; Bates, J.K.; Bradley, C.R.

The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion.This document is organized into three volumes. Volumes I and II represent a tiered set of information intended for somewhat different audiences. Volume I is intended to provide an overview of waste glass corrosion,more » and Volume 11 is intended to provide additional experimental details on experimental factors that influence waste glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II. Volume I is intended for managers, decision makers, and modelers, the combined set of Volumes I, II, and III is intended for scientists and engineers working in the field of high-level waste.« less

Technetium Incorporation in Glass for the Hanford Tank Waste Treatment and Immobilization Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Kim, Dong Sang

2015-01-14

A priority of the United States Department of Energy (U.S. DOE) is to dispose of nuclear wastes accumulated in 177 underground tanks at the Hanford Nuclear Reservation in eastern Washington State. These nuclear wastes date from the Manhattan Project of World War II and from plutonium production during the Cold War. The DOE plans to separate high-level radioactive wastes from low activity wastes and to treat each of the waste streams by vitrification (immobilization of the nuclides in glass) for disposal. The immobilized low-activity waste will be disposed of here at Hanford and the immobilized high-level waste at the nationalmore » geologic repository. Included in the inventory of highly radioactive wastes is large volumes of 99Tc (~9 × 10E2 TBq or ~2.5 × 104 Ci or ~1500 kg). A problem facing safe disposal of Tc-bearing wastes is the processing of waste feed into in a chemically durable waste form. Technetium incorporates poorly into silicate glass in traditional glass melting. It readily evaporates during melting of glass feeds and out of the molten glass, leading to a spectrum of high-to-low retention (ca. 20 to 80%) in the cooled glass product. DOE-ORP currently has a program at Pacific Northwest National Laboratory (PNNL), in the Department of Materials Science and Engineering at Rutgers University and in the School of Mechanical and Materials Engineering at Washington State University that seeks to understand aspects of Tc retention by means of studying Tc partitioning, molten salt formation, volatilization pathways, and cold cap chemistry. Another problem involves the stability of Tc in glass in both the national geologic repository and on-site disposal after it has been immobilized. The major environmental concern with 99Tc is its high mobility in addition to a long half-life (2.1×105 yrs). The pertechnetate ion (TcO4-) is highly soluble in water and does not adsorb well onto the surface of minerals and so migrates nearly at the same velocity as groundwater. Long-term corrosion of glass waste forms is an area of current interest to the DOE, but attention to the release of Tc from glass has been little explored. It is expected that the release of Tc from glass should be highly dependent on the local glass structure as well as the chemistry of the surrounding environment, including groundwater pH. Though the speciation of Tc in glass has been previously studied, and the Tc species present in waste glass have been previously reported, environmental Tc release mechanisms are poorly understood. The recent advances in Tc chemistry that have given rise to an understanding of incorporation in the glass giving rise to significantly higher single-pass retention during vitrification are presented. Additionally, possible changes to the baseline flowsheet that allow for relatively minor volumes of Tc reporting to secondary waste treatment will be discussed.« less

Effects of waste glass additions on quality of textile sludge-based bricks.

PubMed

Rahman, Ari; Urabe, Takeo; Kishimoto, Naoyuki; Mizuhara, Shinji

2015-01-01

This research investigated the utilization of textile sludge as a substitute for clay in brick production. The addition of textile sludge to a brick specimen enhanced its pores, thus reducing the quality of the product. However, the addition of waste glass to brick production materials improved the quality of the brick in terms of both compressive strength and water absorption. Maximum compressive strength was observed with the following composition of waste materials: 30% textile sludge, 60% clay and 10% waste glass. The melting of waste glass clogged up pores on the brick, which improved water absorption performance and compressive strength. Moreover, a leaching test on a sludge-based brick to which 10% waste glass did not detect significant heavy metal compounds in leachates, with the product being in conformance with standard regulations. The recycling of textile sludge for brick production, when combined with waste glass additions, may thus be promising in terms of both product quality and environmental aspects.

Process for treating fission waste

DOEpatents

Rohrmann, Charles A.; Wick, Oswald J.

1983-01-01

A method is described for the treatment of fission waste. A glass forming agent, a metal oxide, and a reducing agent are mixed with the fission waste and the mixture is heated. After melting, the mixture separates into a glass phase and a metal phase. The glass phase may be used to safely store the fission waste, while the metal phase contains noble metals recovered from the fission waste.

Final Report - LAW Envelope A and B Glass Formulations Testing in Increase Waste Loading. VSL-06R6900-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Joseph, I.; Muller, I. S.

This report describes the results of testing specified by the Test Plan VSL-06R6900-1 Rev 0. The work was performed in compliance with quality assurance requirements specified in the Test Plan. Results required by the Test Plan are reported. The test results and this report have been reviewed for correctness, technical adequacy, completeness, and accuracy.

Methods of vitrifying waste with low melting high lithia glass compositions

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

2001-01-01

The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

Process for treating fission waste. [Patent application

DOEpatents

Rohrmann, C.A.; Wick, O.J.

1981-11-17

A method is described for the treatment of fission waste. A glass forming agent, a metal oxide, and a reducing agent are mixed with the fission waste and the mixture is heated. After melting, the mixture separates into a glass phase and a metal phase. The glass phase may be used to safely store the fission waste, while the metal phase contains noble metals recovered from the fission waste.

Nuclear fuel cycle waste stream immobilization with cermets for improved thermal properties and waste consolidation

NASA Astrophysics Data System (ADS)

Ortega, Luis H.; Kaminski, Michael D.; Zeng, Zuotao; Cunnane, James

2013-07-01

In the pursuit of methods to improve nuclear waste form thermal properties and combine potential nuclear fuel cycle wastes, a bronze alloy was combined with an alkali, alkaline earth metal bearing ceramic to form a cermet. The alloy was prepared from copper and tin (10 mass%) powders. Pre-sintered ceramic consisting of cesium, strontium, barium and rubidium alumino-silicates was mixed with unalloyed bronze precursor powders and cold pressed to 300 × 103 kPa, then sintered at 600 °C and 800 °C under hydrogen. Cermets were also prepared that incorporated molybdenum, which has a limited solubility in glass, under similar conditions. The cermet thermal conductivities were seven times that of the ceramic alone. These improved thermal properties can reduce thermal gradients within the waste forms thus lowering internal temperature gradients and thermal stresses, allowing for larger waste forms and higher waste loadings. These benefits can reduce the total number of waste packages necessary to immobilize a given amount of high level waste and immobilize troublesome elements.

Using polymerization, glass structure, and quasicrystalline theory to produce high level radioactive borosilicate glass remotely: a 20+ year legacy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol M.

Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in borosilicate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt a highly variable waste with some glass forming additives such as SiO 2 and B 2O 3 in the form of a premelted frit and pour the molten mixture into a stainless steel canister. Seal the canister before moisture can enter themore » canister (10’ tall by 2’ in diameter) so the canister does not corrode from the inside out. Glass has also become widely used for HLW is that due to the fact that the short range order (SRO) and medium range order (MRO) found in the structure of glass atomistically bonds the radionuclides and hazardous species in the waste. The SRO and MRO have also been found to govern the melt properties such as viscosity and resistivity of the melt and the crystallization potential and solubility of certain species. Furthermore, the molecular structure of the glass also controls the glass durability, i.e. the contaminant/radionuclide release, by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to HLW waste variability. Nuclear waste glasses melt between 1050-1150°C which minimizes the volatility of radioactive components such as 99Tc, 137Cs, and 129I. Nuclear waste glasses have good long term stability including irradiation resistance. Process control models were developed based on the molecular structure of glass, polymerization theory of glass, and quasicrystalline theory of glass crystallization. These models create a glass which is durable, pourable, and processable with 95% accuracy without knowing from batch to batch what the composition of the waste coming out of the storage tanks will be. These models have operated the Savannah River Site Defense Waste Processing Facility (SRS DWPF), which is the world’s largest HLW Joule heated ceramic melter, since 1996. This unique “feed forward” process control, which qualifies the durability, pourability, and processability of the waste plus glass additive mixture before it enters the melter, has enabled ~8000 tons of HLW glass and 4242 canisters to be produced since 1996 with only one melter replacement.« less

Using polymerization, glass structure, and quasicrystalline theory to produce high level radioactive borosilicate glass remotely: a 20+ year legacy

DOE PAGES

Jantzen, Carol M.

2017-03-27

Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in borosilicate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt a highly variable waste with some glass forming additives such as SiO 2 and B 2O 3 in the form of a premelted frit and pour the molten mixture into a stainless steel canister. Seal the canister before moisture can enter themore » canister (10’ tall by 2’ in diameter) so the canister does not corrode from the inside out. Glass has also become widely used for HLW is that due to the fact that the short range order (SRO) and medium range order (MRO) found in the structure of glass atomistically bonds the radionuclides and hazardous species in the waste. The SRO and MRO have also been found to govern the melt properties such as viscosity and resistivity of the melt and the crystallization potential and solubility of certain species. Furthermore, the molecular structure of the glass also controls the glass durability, i.e. the contaminant/radionuclide release, by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to HLW waste variability. Nuclear waste glasses melt between 1050-1150°C which minimizes the volatility of radioactive components such as 99Tc, 137Cs, and 129I. Nuclear waste glasses have good long term stability including irradiation resistance. Process control models were developed based on the molecular structure of glass, polymerization theory of glass, and quasicrystalline theory of glass crystallization. These models create a glass which is durable, pourable, and processable with 95% accuracy without knowing from batch to batch what the composition of the waste coming out of the storage tanks will be. These models have operated the Savannah River Site Defense Waste Processing Facility (SRS DWPF), which is the world’s largest HLW Joule heated ceramic melter, since 1996. This unique “feed forward” process control, which qualifies the durability, pourability, and processability of the waste plus glass additive mixture before it enters the melter, has enabled ~8000 tons of HLW glass and 4242 canisters to be produced since 1996 with only one melter replacement.« less

X-ray absorption and Raman spectroscopy studies of molybdenum environments in borosilicate waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKeown, David A.; Gan, Hao; Pegg, Ian L.

2017-05-01

Mo-containing high-level nuclear waste borosilicate glasses were investigated as part of an effort to improve Mo loading while avoiding yellow phase crystallization. Previous work showed that additions of vanadium decrease yellow phase formation and increases Mo solubility. X-ray absorption spectroscopy (XAS) and Raman spectroscopy were used to characterize Mo environments in HLW borosilicate glasses and to investigate possible structural relationships between Mo and V. Mo XAS spectra for the glasses indicate isolated tetrahedral Mo6+O4 with Mo-O distances near 1.75 Å. V XANES indicate tetrahedral V5+O4 as the dominant species. Raman spectra show composition dependent trends, where Mo-O symmetrical stretch modemore » frequencies (ν1) are sensitive to the mix of alkali and alkaline earth cations, decreasing by up to 10 cm-1 for glasses that change from Li+ to Na+ as the dominant network-modifying species. This indicates that MoO4 tetrahedra are isolated from the borosilicate network and are surrounded, at least partly, by Na+ and Li+. Secondary ν1 frequency effects, with changes up to 7 cm-1, were also observed with increasing V2O5 and MoO3 content. These secondary trends may indicate MoO4-MoO4 and MoO4-VO4 clustering, suggesting that V additions may stabilize Mo in the matrix with respect to yellow phase formation.« less

Radioactive Waste Conditioning, Immobilisation, And Encapsulation Processes And Technologies: Overview And Advances (Chapter 7)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol M.; Lee, William E.; Ojovan, Michael I.

The main immobilization technologies that are available commercially and have been demonstrated to be viable are cementation, bituminization, and vitrification. Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either alkali borosilicate glass or alkali aluminophosphate glass. The exact compositions of nuclear waste glasses are tailored for easy preparation and melting, avoidance of glass-in-glass phase separation, avoidance of uncontrolled crystallization, and acceptable chemical durability, e.g., leach resistance. Glass has also been used to stabilize a variety of lowmore » level wastes (LLW) and mixed (radioactive and hazardous) low level wastes (MLLW) from other sources such as fuel rod cladding/decladding processes, chemical separations, radioactive sources, radioactive mill tailings, contaminated soils, medical research applications, and other commercial processes. The sources of radioactive waste generation are captured in other chapters in this book regarding the individual practices in various countries (legacy wastes, currently generated wastes, and future waste generation). Future waste generation is primarily driven by interest in sources of clean energy and this has led to an increased interest in advanced nuclear power production. The development of advanced wasteforms is a necessary component of the new nuclear power plant (NPP) flowsheets. Therefore, advanced nuclear wasteforms are being designed for robust disposal strategies. A brief summary is given of existing and advanced wasteforms: glass, glass-ceramics, glass composite materials (GCM’s), and crystalline ceramic (mineral) wasteforms that chemically incorporate radionuclides and hazardous species atomically in their structure. Cementitious, geopolymer, bitumen, and other encapsulant wasteforms and composites that atomically bond and encapsulate wastes are also discussed. The various processing technologies are cross-referenced to the various types of wasteforms since often a particular type of wasteform can be made by a variety of different processing technologies.« less

High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cunnane, J.C.; Bates, J.K.; Bradley, C.R.

1994-03-01

The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II.

Leaching of plutonium from a radioactive waste glass by eight groundwaters from the western United States

USGS Publications Warehouse

Rees, T.F.; Cleveland, J.M.; Nash, K.L.

1985-01-01

The leachability of a radioactive waste glass formulated to Battelle Pacific Northwest Laboratory specification 80-270 has been studied using eight actual groundwaters with a range of chemical compositions as leachants. Waters collected from the Grande Ronde Basalt (Washington State) and from alluvial deposits in the Hualapai Valley (Arizona) were the most effective at removing plutonium from this glass. Leaching was shown to be incongruent; plutonium was removed from the glass more slowly than the overall glass matrix. The results of these experiments indicate the need to study the leachability of actual waste forms using the actual projected groundwaters that are most likely to come into contact with the waste should a radioactive waste repository be breached.

Candidate waste forms for immobilisation of waste chloride salt from pyroprocessing of spent nuclear fuel

NASA Astrophysics Data System (ADS)

Vance, E. R.; Davis, J.; Olufson, K.; Chironi, I.; Karatchevtseva, I.; Farnan, I.

2012-01-01

Sodalite/glass bodies prepared by hot isostatic pressing (HIPing) at ˜850 °C/100 MPa are candidates for immobilising fission product-bearing waste KCl-LiCl pyroprocessing salts. To study the capacity of sodalite to structurally incorporate such pyroprocessing salts, K, Li, Cs, Sr, Ba and La were individually targeted for substitution in a Na site in sodalite (Na vacancies targeted as charge compensators for alkaline and rare earths) and studied by X-ray diffraction and scanning electron microscopy after sintering in the range of 800-1000 °C. K and Li appeared to enter the sodalite, but Cs, Sr and Ba formed aluminosilicate phases and La formed an oxyapatite phase. However these non-sodalite phases have reasonable resistance to water leaching. Pure chlorapatite gives superior leach resistance to sodalite, and alkalis, alkaline and rare earth ions are generally known to enter chlorapatite, but attempts to incorporate simulated waste salt formulations into HIPed chlorapatite-based preparations or to substitute Cs alone into the structure of Ca-based chlorapatite were not successful on the basis of scanning electron microscopy. The materials exhibited severe water leachability, mainly in regard to Cs release. Attempts to substitute Cs into Ba- and Sr-based chlorapatites also did not look encouraging. Consequently the use of apatite alone to retain fission product-bearing waste pyroprocessing salts from electrolytic nuclear fuel reprocessing is problematical, but chlorapatite glass-ceramics may be feasible, albeit with reduced waste loadings. Spodiosite, Ca 2(PO 4)Cl, does not appear to be suitable for incorporation of Cl-bearing waste containing fission products.

Inhibitory Effect of Waste Glass Powder on ASR Expansion Induced by Waste Glass Aggregate

PubMed Central

Liu, Shuhua; Wang, Shu; Tang, Wan; Hu, Ningning; Wei, Jianpeng

2015-01-01

Detailed research is carried out to ascertain the inhibitory effect of waste glass powder (WGP) on alkali-silica reaction (ASR) expansion induced by waste glass aggregate in this paper. The alkali reactivity of waste glass aggregate is examined by two methods in accordance with the China Test Code SL352-2006. The potential of WGP to control the ASR expansion is determined in terms of mean diameter, specific surface area, content of WGP and curing temperature. Two mathematical models are developed to estimate the inhibitory efficiency of WGP. These studies show that there is ASR risk with an ASR expansion rate over 0.2% when the sand contains more than 30% glass aggregate. However, WGP can effectively control the ASR expansion and inhibit the expansion rate induced by the glass aggregate to be under 0.1%. The two mathematical models have good simulation results, which can be used to evaluate the inhibitory effect of WGP on ASR risk. PMID:28793603

Developing Specifications for Waste Glass, Municipal Waste Combustor Ash and Waste Tires as Highway Fill Materials (Continuation). Final Report. Volume 3. Waste Tires.

DOT National Transportation Integrated Search

1995-04-01

A two year study was conducted as a continuation project for the Florida Department of Transportation (FDOT) to evaluate Municipal Waste Combustor (MWC) ash, Waste Glass, and Waste Tires for use as general highway fill. Initial studies conducted at F...

Compositional Models of Glass/Melt Properties and their Use for Glass Formulation

DOE PAGES

Vienna, John D.; USA, Richland Washington

2014-12-18

Nuclear waste glasses must simultaneously meet a number of criteria related to their processability, product quality, and cost factors. The properties that must be controlled in glass formulation and waste vitrification plant operation tend to vary smoothly with composition allowing for glass property-composition models to be developed and used. Models have been fit to the key glass properties. The properties are transformed so that simple functions of composition (e.g., linear, polynomial, or component ratios) can be used as model forms. The model forms are fit to experimental data designed statistically to efficiently cover the composition space of interest. Examples ofmore » these models are found in literature. The glass property-composition models, their uncertainty definitions, property constraints, and optimality criteria are combined to formulate optimal glass compositions, control composition in vitrification plants, and to qualify waste glasses for disposal. An overview of current glass property-composition modeling techniques is summarized in this paper along with an example of how those models are applied to glass formulation and product qualification at the planned Hanford high-level waste vitrification plant.« less

Waste glass as eco-friendly replacement material in construction products

NASA Astrophysics Data System (ADS)

Sharma, Gayatri; Sharma, Anu

2018-05-01

Atpresent time the biggest issue is increasing urban population, industrialization and development all over the world. The quantity of the raw materials of construction products like cement, concrete etc is gradually depleting. This is important because if we don't find the alternative material to accomplish need of this industry, with every year it will put pressure on natural resources which are limited in quantity. This major issue can be solved by partial replacing with waste glass of different construction products. This paper gives an overview of the current growth and recycling situation of waste glass and point out the direction for the proper use of waste glass as replacement of construction material. These will not only help in the reuse of waste glass but also create eco-friendly environment.

Evaluation of the Effects of Crushed and Expanded Waste Glass Aggregates on the Material Properties of Lightweight Concrete Using Image-Based Approaches

PubMed Central

Abd Elrahman, Mohamed; Sikora, Pawel; Rucinska, Teresa; Horszczaruk, Elzbieta

2017-01-01

Recently, the recycling of waste glass has become a worldwide issue in the reduction of waste and energy consumption. Waste glass can be utilized in construction materials, and understanding its effects on material properties is crucial in developing advanced materials. In this study, recycled crushed and expanded glasses are used as lightweight aggregates for concrete, and their relation to the material characteristics and properties is investigated using several approaches. Lightweight concrete specimens containing only crushed and expanded waste glass as fine aggregates are produced, and their pore and structural characteristics are examined using image-based methods, such as scanning electron microscopy (SEM), X-ray computed tomography (CT), and automated image analysis (RapidAir). The thermal properties of the materials are measured using both Hot Disk and ISOMET devices to enhance measurement accuracy. Mechanical properties are also evaluated, and the correlation between material characteristics and properties is evaluated. As a control group, a concrete specimen with natural fine sand is prepared, and its characteristics are compared with those of the specimens containing crushed and expanded waste glass aggregates. The obtained results support the usability of crushed and expanded waste glass aggregates as alternative lightweight aggregates. PMID:29186854

Evaluation of the Effects of Crushed and Expanded Waste Glass Aggregates on the Material Properties of Lightweight Concrete Using Image-Based Approaches.

PubMed

Chung, Sang-Yeop; Abd Elrahman, Mohamed; Sikora, Pawel; Rucinska, Teresa; Horszczaruk, Elzbieta; Stephan, Dietmar

2017-11-25

Recently, the recycling of waste glass has become a worldwide issue in the reduction of waste and energy consumption. Waste glass can be utilized in construction materials, and understanding its effects on material properties is crucial in developing advanced materials. In this study, recycled crushed and expanded glasses are used as lightweight aggregates for concrete, and their relation to the material characteristics and properties is investigated using several approaches. Lightweight concrete specimens containing only crushed and expanded waste glass as fine aggregates are produced, and their pore and structural characteristics are examined using image-based methods, such as scanning electron microscopy (SEM), X-ray computed tomography (CT), and automated image analysis (RapidAir). The thermal properties of the materials are measured using both Hot Disk and ISOMET devices to enhance measurement accuracy. Mechanical properties are also evaluated, and the correlation between material characteristics and properties is evaluated. As a control group, a concrete specimen with natural fine sand is prepared, and its characteristics are compared with those of the specimens containing crushed and expanded waste glass aggregates. The obtained results support the usability of crushed and expanded waste glass aggregates as alternative lightweight aggregates.

Operation costs and pollutant emissions reduction by definition of new collection scheduling and optimization of MSW collection routes using GIS. The case study of Barreiro, Portugal.

PubMed

Zsigraiova, Zdena; Semiao, Viriato; Beijoco, Filipa

2013-04-01

This work proposes an innovative methodology for the reduction of the operation costs and pollutant emissions involved in the waste collection and transportation. Its innovative feature lies in combining vehicle route optimization with that of waste collection scheduling. The latter uses historical data of the filling rate of each container individually to establish the daily circuits of collection points to be visited, which is more realistic than the usual assumption of a single average fill-up rate common to all the system containers. Moreover, this allows for the ahead planning of the collection scheduling, which permits a better system management. The optimization process of the routes to be travelled makes recourse to Geographical Information Systems (GISs) and uses interchangeably two optimization criteria: total spent time and travelled distance. Furthermore, rather than using average values, the relevant parameters influencing fuel consumption and pollutant emissions, such as vehicle speed in different roads and loading weight, are taken into consideration. The established methodology is applied to the glass-waste collection and transportation system of Amarsul S.A., in Barreiro. Moreover, to isolate the influence of the dynamic load on fuel consumption and pollutant emissions a sensitivity analysis of the vehicle loading process is performed. For that, two hypothetical scenarios are tested: one with the collected volume increasing exponentially along the collection path; the other assuming that the collected volume decreases exponentially along the same path. The results evidence unquestionable beneficial impacts of the optimization on both the operation costs (labor and vehicles maintenance and fuel consumption) and pollutant emissions, regardless the optimization criterion used. Nonetheless, such impact is particularly relevant when optimizing for time yielding substantial improvements to the existing system: potential reductions of 62% for the total spent time, 43% for the fuel consumption and 40% for the emitted pollutants. This results in total cost savings of 57%, labor being the greatest contributor, representing over €11,000 per year for the two vehicles collecting glass-waste. Moreover, it is shown herein that the dynamic loading process of the collection vehicle impacts on both the fuel consumption and on pollutant emissions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Demonstrate Scale-up Procedure for Glass Composite Material (GCM) for Incorporation of Iodine Loaded AgZ.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nenoff, Tina M.; Garino, Terry J.; Croes, Kenneth James

2015-07-01

Two large size Glass Composite Material (GCM) waste forms containing AgI-MOR were fabricated. One contained methyl iodide-loaded AgI-MOR that was received from Idaho National Laboratory (INL, Test 5, Beds 1 – 3) and the other contained iodine vapor loaded AgIMOR that was received from Oak Ridge National Laboratory (ORNL, SHB 2/9/15 ). The composition for each GCM was 20 wt% AgI-MOR and 80 wt% Ferro EG2922 low sintering temperature glass along with enough added silver flake to prevent any I2 loss during the firing process. The silver flake amounts were 1.2 wt% for the GCM with the INL AgI-MOR andmore » 3 wt% for the GCM contained the ORNL AgI-MOR. The GCMs, nominally 100 g, were first uniaxially pressed to 6.35 cm (2.5 inch) diameter disks then cold isostatically pressed, before firing in air to 550°C for 1hr. They were cooled slowly (1°C/min) from the firing temperature to avoid any cracking due to temperature gradients. The final GCMs were ~5 cm in diameter (~2 inches) and non-porous with densities of ~4.2 g/cm³. X-ray diffraction indicated that they consisted of the amorphous glass phase with small amounts of mordenite and AgI. Furthermore, the presence of the AgI was confirmed by X-ray fluorescence. Methodology for the scaled up production of GCMs to 6 inch diameter or larger is also presented.« less

Examining the role of canister cooling conditions on the formation of nepheline from nuclear waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christian, J. H.

2015-09-01

Nepheline (NaAlSiO₄) crystals can form during slow cooling of high-level waste (HLW) glass after it has been poured into a waste canister. Formation of these crystals can adversely affect the chemical durability of the glass. The tendency for nepheline crystallization to form in a HLW glass increases with increasing concentrations of Al₂O₃ and Na₂O.

Ensuring Longevity: Ancient Glasses Help Predict Durability of Vitrified Nuclear Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weaver, Jamie L.; McCloy, John S.; Ryan, Joseph V.

How does glass alter with time? For the last hundred years this has been an important question to the fields of object conservation and archeology to ensure the preservation of glass artifacts. This same question is part of the development and assessment of durable glass waste forms for the immobilization of nuclear wastes. Researchers have developed experiments ranging from simple to highly sophisticated to answer this question, and, as a result, have gained significant insight into the mechanisms that drive glass alteration. However, the gathered data have been predominately applicable to only short-term alteration times, i.e. over the course ofmore » decades. What has remained elusive is the long-term mechanisms of glass alteration[1]. These mechanisms are of particular interest to the international nuclear waste glass community as they strive to ensure that vitrified products will be durable for thousands to tens of thousands of years. For the last thirty years this community has been working to fill this research gap by partnering with archeologists, museum curators, and geologists to identify hundred to million-year old glass analogues that have altered in environments representative of those expected at potential nuclear waste disposal sites. The process of identifying a waste glass relevant analogue is challenging as it requires scientists to relate data collected from short-term laboratory experiments to observations made from long-term analogues and extensive geochemical modeling.« less

Low melting high lithia glass compositions and methods

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

2004-11-02

The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

Low melting high lithia glass compositions and methods

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

2003-10-07

The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

Low melting high lithia glass compositions and methods

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

2000-01-01

The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

Final Report - Testing of Optimized Bubbler Configuration for HLW Melter VSL-13R2950-1, Rev. 0, dated 6/12/2013

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Pegg, I. L.; Callow, R. A.

2013-11-13

The principal objective of this work was to determine the glass production rate increase and ancillary effects of adding more bubbler outlets to the current WTP HLW melter baseline. This was accomplished through testing on the HLW Pilot Melter (DM1200) at VSL. The DM1200 unit was selected for these tests since it was used previously with several HLW waste streams including the four tank wastes proposed for initial processing at Hanford. This melter system was also used for the development and optimization of the present baseline WTP HLW bubbler configuration for the WTP HLW melter, as well as for MACTmore » testing for both HLW and LAW. Specific objectives of these tests were to: Conduct DM1200 melter testing with the baseline WTP bubbling configuration and as augmented with additional bubblers. Conduct DM1200 melter testing to differentiate the effects of total bubbler air flow and bubbler distribution on glass production rate and cold cap formation. Collect melter operating data including processing rate, temperatures at a variety of locations within the melter plenum space, melt pool temperature, glass melt density, and melter pressure with the baseline WTP bubbling configuration and as augmented with additional bubblers. Collect melter exhaust samples to compare particulate carryover for different bubbler configurations. Analyze all collected data to determine the effects of adding more bubblers to the WTP HLW melter to inform decisions regarding future lid re-designs. The work used a high aluminum HLW stream composition defined by ORP, for which an appropriate simulant and high waste loading glass formulation were developed and have been previously processed on the DM1200.« less

REDUCTION OF CONSTRAINTS FOR COUPLED OPERATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raszewski, F.; Edwards, T.

2009-12-15

The homogeneity constraint was implemented in the Defense Waste Processing Facility (DWPF) Product Composition Control System (PCCS) to help ensure that the current durability models would be applicable to the glass compositions being processed during DWPF operations. While the homogeneity constraint is typically an issue at lower waste loadings (WLs), it may impact the operating windows for DWPF operations, where the glass forming systems may be limited to lower waste loadings based on fissile or heat load limits. In the sludge batch 1b (SB1b) variability study, application of the homogeneity constraint at the measurement acceptability region (MAR) limit eliminated muchmore » of the potential operating window for DWPF. As a result, Edwards and Brown developed criteria that allowed DWPF to relax the homogeneity constraint from the MAR to the property acceptance region (PAR) criterion, which opened up the operating window for DWPF operations. These criteria are defined as: (1) use the alumina constraint as currently implemented in PCCS (Al{sub 2}O{sub 3} {ge} 3 wt%) and add a sum of alkali constraint with an upper limit of 19.3 wt% ({Sigma}M{sub 2}O < 19.3 wt%), or (2) adjust the lower limit on the Al{sub 2}O{sub 3} constraint to 4 wt% (Al{sub 2}O{sub 3} {ge} 4 wt%). Herman et al. previously demonstrated that these criteria could be used to replace the homogeneity constraint for future sludge-only batches. The compositional region encompassing coupled operations flowsheets could not be bounded as these flowsheets were unknown at the time. With the initiation of coupled operations at DWPF in 2008, the need to revisit the homogeneity constraint was realized. This constraint was specifically addressed through the variability study for SB5 where it was shown that the homogeneity constraint could be ignored if the alumina and alkali constraints were imposed. Additional benefit could be gained if the homogeneity constraint could be replaced by the Al{sub 2}O{sub 3} and sum of alkali constraint for future coupled operations processing based on projections from Revision 14 of the High Level Waste (HLW) System Plan. As with the first phase of testing for sludge-only operations, replacement of the homogeneity constraint with the alumina and sum of alkali constraints will ensure acceptable product durability over the compositional region evaluated. Although these study glasses only provide limited data in a large compositional region, the approach and results are consistent with previous studies that challenged the homogeneity constraint for sludge-only operations. That is, minimal benefit is gained by imposing the homogeneity constraint if the other PCCS constraints are satisfied. The normalized boron releases of all of the glasses are well below the Environmental Assessment (EA) glass results, regardless of thermal history. Although one of the glasses had a normalized boron release of approximately 10 g/L and was not predictable, the glass is still considered acceptable. This particular glass has a low Al{sub 2}O{sub 3} concentration, which may have attributed to the anomalous behavior. Given that poor durability has been previously observed in other glasses with low Al{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} concentrations, including the sludge-only reduction of constraints study, further investigations appear to be warranted. Based on the results of this study, it is recommended that the homogeneity constraint (in its entirety with the associated low frit/high frit constraints) be eliminated for coupled operations as defined by Revision 14 of the HLW System Plan with up to 2 wt% TiO{sub 2}. The use of the alumina and sum of alkali constraints should be continued along with the variability study to determine the predictability of the current durability models and/or that the glasses are acceptable with respect to durability. The use of a variability study for each batch is consistent with the glass product control program and it will help to assess new streams or compositional changes. It is also recommended that the influence of alumina and alkali on durability be studied in greater detail. Limited data suggests that there may be a need to adjust the lower Al{sub 2}O{sub 3} limit and/or the upper alkali limit in order to prevent the fabrication of unacceptable glasses. An in-depth evaluation of all previous data as well as any new data would help to better define an alumina and alkali combination that would avoid potential phase separation and ensure glass durability.« less

Proceedings of Symposium on Utilization of Waste Glass in Secondary Products

NASA Technical Reports Server (NTRS)

1973-01-01

Papers are reported which were presented at the conference on waste glass recovery and re-use in secondary products. The uses considered include: road surfacing, asphaltic concretes, road construction, terrazzo, cement concrete, pozzolan, glass wool, glass-polymer composites, and tiles. Problems of recycling glass in remote areas, and the economics and markets for secondary glass products are discussed.

Developing Specifications for Waste Glass, Municipal Waste Combustor Ash and Waste Tires as Highway Fill Materials (Continuation): Final Report. Volume 1. Municipal Waste Combustor Ash.

DOT National Transportation Integrated Search

1995-04-01

A two year study was conducted as a continuation project for the Florida Department of Transportation (FDOT) to evlauate Municipal Waste Combustor (MWC) ash, Waste Glass, and Waste Tires for use as general highway fill. Initial studies conducted at F...

Waste form evaluation for RECl 3 and REO x fission products separated from used electrochemical salt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Pierce, David A.; Crum, Jarrod V.

The work presented here is based off the concept that the rare earth chloride (RECl3) fission products mixture within the used electrorefiner (ER) salt can be selectively removed as RECl3 (not yet demonstrated) or precipitated out as REOCl through oxygen sparging (has been demonstrated). This paper presents data showing the feasibility of immobilizing a mixture of RECl3’s at 10 mass% into a TeO2-PbO glass and it shows that this same mixture of RECl3’s can be oxidized to REOCl at 300°C and then to REOx by 1200°C. When the REOx mixture is heated at temperatures >1200°C, the ratios of REOx’s change.more » The mixture of REOx was then immobilized in a LABS glass at a high loading of 60 mass%. Both the TeO2-PbO glass and LABS glass systems show good chemical durability. The advantages and disadvantages of tellurite and LABS glasses are compared.« less

Ceramics in nuclear waste management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chikalla, T D; Mendel, J E

1979-05-01

Seventy-three papers are included, arranged under the following section headings: national programs for the disposal of radioactive wastes, waste from stability and characterization, glass processing, ceramic processing, ceramic and glass processing, leaching of waste materials, properties of nuclear waste forms, and immobilization of special radioactive wastes. Separate abstracts were prepared for all the papers. (DLC)

Sodalite as a vehicle to increase Re retention in waste glass simulant during vitrification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luksic, Steven A.; Riley, Brian J.; Parker, Kent E.

Technetium retention during Hanford waste vitrification can be increased by inhibiting technetium volatility from the waste glass melter. Incorporating technetium into a mineral phase, such as sodalite, is one way to achieve this. Rhenium-bearing sodalite was tested as a vehicle to transport perrhenate (ReO4-), a nonradioactive surrogate for pertechnetate (TcO4-), into high-level (HLW) and low-activity waste (LAW) glasses. After melting feeds of these two glasses, the retention of rhenium was measured and compared with the rhenium retention in glass prepared from a feed containing Re2O7 as a standard. The rhenium retention was 21% higher for HLW glass and 85% highermore » for LAW glass when added to samples in the form of sodalite as opposed to when it was added as Re2O7, demonstrating the efficacy of this type of an approach.« less

Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes

DOEpatents

Boatner, L.A.; Sales, B.C.

1984-04-11

Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

Use of crushed recycled glass in the construction of local roadways current status of recycled glass collection and processing in the State of Ohio.

DOT National Transportation Integrated Search

2017-05-01

Junliang (Julian) Tao, ORCiD: 0000-0002-3772-3099 : Glass cullet is produced from crushing waste glass collected in municipal and industrial waste streams to a specific size. In Ohio, it is primarily used in new glass container manufacturing. One pos...

Phase Stability Determinations of DWPF Waste Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marra, S.L.

1999-10-22

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. To fulfill this requirement, glass samples were heat treated at various times and temperatures. These results will provide guidance to the repository program about conditions to be avoided during shipping, handling and storage of DWPF canistered waste forms.

Prediction of glass durability as a function of environmental conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C M

1988-01-01

A thermodynamic model of glass durability is applied to natural, ancient, and nuclear waste glasses. The durabilities of over 150 different natural and man-made glasses, including actual ancient Roman and Islamic glasses (Jalame ca. 350 AD, Nishapur 10-11th century AD and Gorgon 9-11th century AD), are compared. Glass durability is a function of the thermodynamic hydration free energy, ..delta..G/sub hyd/, which can be calculated from glass composition and solution pH. The durability of the most durable nuclear waste glasses examined was /approximately/10/sup 6/ years. The least durable waste glass formulations were comparable in durability to the most durable simulated medievalmore » window glasses of /approximately/10/sup 3/ years. In this manner, the durability of nuclear waste glasses has been interpolated to be /approximately/10/sup 6/ years and no less than 10/sup 3/ years. Hydration thermodynamics have been shown to be applicable to the dissolution of glass in various natural environments. Groundwater-glass interactions relative to geologic disposal of nuclear waste, hydration rind dating of obsidians, andor other archeological studies can be modeled, e.g., the relative durabilities of six simulated medieval window glasses have been correctly predicted for both laboratory (one month) and burial (5 years) experiments. Effects of solution pH on glass dissolution has been determined experimentally for the 150 different glasses and can be predicted theoretically by hydration thermodynamics. The effects of solution redox on dissolution of glass matrix elements such as SI and B have shown to be minimal. The combined effects of solution pH and Eh have been described and unified by construction of thermodynamically calculated Pourbaix (pH-Eh) diagrams for glass dissolution. The Pourbaix diagrams have been quantified to describe glass dissolution as a function of environmental conditions by use of the data derived from hydration thermodynamics. 56 refs., 7 figs.« less

DESIGN ANALYSIS FOR THE DEFENSE HIGH-LEVEL WASTE DISPOSAL CONTAINER

DOE Office of Scientific and Technical Information (OSTI.GOV)

G. Radulesscu; J.S. Tang

The purpose of ''Design Analysis for the Defense High-Level Waste Disposal Container'' analysis is to technically define the defense high-level waste (DHLW) disposal container/waste package using the Waste Package Department's (WPD) design methods, as documented in ''Waste Package Design Methodology Report'' (CRWMS M&O [Civilian Radioactive Waste Management System Management and Operating Contractor] 2000a). The DHLW disposal container is intended for disposal of commercial high-level waste (HLW) and DHLW (including immobilized plutonium waste forms), placed within disposable canisters. The U.S. Department of Energy (DOE)-managed spent nuclear fuel (SNF) in disposable canisters may also be placed in a DHLW disposal container alongmore » with HLW forms. The objective of this analysis is to demonstrate that the DHLW disposal container/waste package satisfies the project requirements, as embodied in Defense High Level Waste Disposal Container System Description Document (SDD) (CRWMS M&O 1999a), and additional criteria, as identified in Waste Package Design Sensitivity Report (CRWMS M&Q 2000b, Table 4). The analysis briefly describes the analytical methods appropriate for the design of the DHLW disposal contained waste package, and summarizes the results of the calculations that illustrate the analytical methods. However, the analysis is limited to the calculations selected for the DHLW disposal container in support of the Site Recommendation (SR) (CRWMS M&O 2000b, Section 7). The scope of this analysis is restricted to the design of the codisposal waste package of the Savannah River Site (SRS) DHLW glass canisters and the Training, Research, Isotopes General Atomics (TRIGA) SNF loaded in a short 18-in.-outer diameter (OD) DOE standardized SNF canister. This waste package is representative of the waste packages that consist of the DHLW disposal container, the DHLW/HLW glass canisters, and the DOE-managed SNF in disposable canisters. The intended use of this analysis is to support Site Recommendation reports and to assist in the development of WPD drawings. Activities described in this analysis were conducted in accordance with the Development Plan ''Design Analysis for the Defense High-Level Waste Disposal Container'' (CRWMS M&O 2000c) with no deviations from the plan.« less

Localized chemistry of 99Tc in simulated low activity waste glass

NASA Astrophysics Data System (ADS)

Weaver, Jamie L.

A priority of the United States Department of Energy (DOE) is to dispose of the nuclear waste accumulated in the underground tanks at the Hanford Nuclear Reservation in Richland, WA. Incorporation and stabilization of technetium (99Tc) from these tanks into vitrified waste forms is a concern to the waste glass community and DOE due to 99Tc's long half-life ( 2.13˙105 y), and its high mobility in the subsurface environment under oxidizing conditions. Working in collaboration with researchers at Pacific Northwest National Laboratory (PNNL) and other national laboratories, plans were formulated to obtain first-of-a-kind chemical structure determination of poorly understood and environmentally relevant technetium compounds that relate to the chemistry of the Tc in nuclear waste glasses. Knowledge of the structure and spectral signature of these compounds aid in refining the understanding of 99Tc incorporation into and release from oxide based waste glass. In this research a first-of-its kind mechanism for the behavior of 99Tc during vitrification is presented, and the structural role of Tc(VII) and (IV) in borosilicate waste glasses is readdressed.

Characterization of Incorporation the Glass Waste in Adhesive Mortar

NASA Astrophysics Data System (ADS)

Santos, D. P.; Azevedo, A. R. G.; Hespanhol, R. L.; Alexandre, J.

Ehe search for reuse generated waste in urban centers, intending to preserve natural resources, has remained fairly constant, both in context of preventing exploitation of resources as the emplacement of waste on the environment. Glass waste glass created a serious environmental problem, mainly because of inconsistency of its flows. Ehe use of this product as a mineral additive, finely ground, cement replacement and aggregate is a promising direction for recycling. This work aims to study the influence of glass waste from cutting process in adhesive mortar, replacing part of cement. Ehe glass powder is used replacing Portland cement at 10, 15 and 20% by mass. Ehe produced mortars will be evaluated its performance in fresh and hardened states through tests performed in laboratory. Ehe selected feature is indicated by producers of additive and researchers to present good results when used as adhesive mortar.

Research on the Properties of the Waste Glass Concrete Composite Foundation

NASA Astrophysics Data System (ADS)

Jia, Shilong; Chen, Kaihui; Chen, Zhongliang

2018-02-01

The composite foundation of glass concrete can not only reuse the large number of waste glass, but also improve the bearing capacity of weak foundation and soil with special properties. In this paper, the engineering properties of glass concrete composite foundation are studied based on the development situation of glass concrete and the technology of composite foundation.

Ion Exchange Column Tests Supporting Technetium Removal Resin Maturation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nash, C.; McCabe, D.; Hamm, L.

2013-12-20

The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant, currently under construction. The baseline plan for this facility is to treat the waste, splitting it into High Level Waste (HLW) and Low Activity Waste (LAW). Both waste streams are then separately vitrified as glass and sealed in canisters. The LAW glass will be disposed on site. There are currently no plans to treat the waste to remove technetium, so its disposition path is the LAW glass. Due to the soluble properties of pertechnetate and long half-life ofmore » 99Tc, effective management of 99Tc is important. Options are being explored to immobilize the supplemental LAW portion of the tank waste, as well as to examine the volatility of 99Tc during the vitrification process. Removal of 99Tc, followed by off-site disposal has potential to reduce treatment and disposal costs. A conceptual flow sheets for supplemental LAW treatment and disposal that could benefit from technetium removal will specifically examine removing 99Tc from the LAW feed stream to supplemental immobilization. SuperLig® 639 is an elutable ion exchange resin. In the tank waste, 99Tc is predominantly found in the tank supernate as pertechnetate (TcO 4 -). Perrhenate (ReO 4 -) has been shown to be a good non-radioactive surrogate for pertechnetate in laboratory testing for this ion exchange resin. This report contains results of experimental ion exchange distribution coefficient and column resin maturation kinetics testing using the resin SuperLig® 639a to selectively remove perrhenate from simulated LAW. This revision includes results from testing to determine effective resin operating temperature range. Loading tests were performed at 45°C, and the computer modeling was updated to include the temperature effects. Equilibrium contact testing indicated that this batch of SuperLig® 639 resin has good performance, with an average perrhenate distribution coefficient of 291 mL/g at a 100:1 phase ratio. This slightly exceeds the computer-modeled equilibrium distribution. The modeling agreed well with the experimental data for perrhenate removal with minor adjustments. Predicted breakthrough performance was on average within about 20% of measured values.« less

Progress in the Assessment of Waste-forms for the Immobilisation of UK Civil Plutonium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrison, M.T.; Scales, C.R.; Maddrell, E.R.

The alternatives for the disposition of the UK's civil plutonium stocks are currently being investigated by Nexia Solutions Ltd. on behalf of the Nuclear Decommissioning Authority (NDA). A number of scenarios are currently being considered depending on the strategic requirements of the UK. The two main disposition options are: re-use as MOX (Mixed Oxide) fuel in reactors, or immobilisation in the event of any material being declared surplus to requirements. The amount of Pu which will require immobilisation will depend on future UK nuclear strategy, along with the extent of any stocks deemed unsuitable for re-use. However, it is likelymore » that some portion will have to be immobilised and therefore three credible waste-forms are under consideration; ceramic, glass and 'immobilisation' MOX. These are currently being developed and assessed in a systematic programme that involves periodic evaluation against a range of criteria. In this way, by down-selecting on the basis of robust and technical review, the most appropriate option for immobilising surplus civil plutonium in the UK can be recommended. The latest results from the immobilisation experimental programme are presented following the de-selection of the least favourable glass and ceramic candidates. The main criteria for this decision were waste loading, durability, processability, criticality and proliferation resistance. In addition, the durability of unirradiated MOX fuel is being examined to determine its potential as a wasteform for Pu, and recent leach test data is discussed. The current evaluation comprises not only a comparison of the relevant physical properties of the various waste-forms, but also key processing parameters, e.g. glass viscosity and melter technology, ceramic fabrication routes, and criticality issues. Other important aspects of the long-term behaviour of the waste-forms under consideration in a potential repository environment, such as radiation damage, criticality control and the properties of any neutron poisons present, are also included. (authors)« less

Microwave-specific heating of crystalline species in nuclear waste glass

DOE PAGES

Christian, Jonathan H.; Fox, Kevin M.; Washington, Aaron L.

2016-08-03

Here, the microwave heating of a crystal-free and a partially trevorite-crystallized nuclear waste glass simulant was evaluated. Our results show that a 500-mg monolith of partially crystallized waste glass can be heated from room temperature to above 1600°C within 2 min using a single-mode, highly focused, 2.45 GHz microwave, operating at 300 W. Using X-ray diffraction measurements, we show that trevorite is no longer detectable after irradiation and thermal quenching. When a crystal-free analog of the same waste glass simulant composition was exposed to the same microwave radiation, it could not be heated above 450°C regardless of the heating time.more » The reduction in crystalline content achieved by selectively heating spinels in the presence of glass suggests that microwave-specific heating should be further explored as a technique for remediating crystal accumulation in a glass melt.« less

High metal reactivity and environmental risks at a site contaminated by glass waste.

PubMed

Augustsson, A; Åström, M; Bergbäck, B; Elert, M; Höglund, L O; Kleja, D B

2016-07-01

This study addresses the reactivity and risks of metals (Ba, Cd, Co, Cr, Cu, Ni, Pb, Zn, As and Sb) at a Swedish site with large glass waste deposits. Old glassworks sites typically have high total metal concentrations, but as the metals are mainly bound within the glass waste and considered relatively inert, environmental investigations at these kinds of sites are limited. In this study, soil and landfill samples were subjected to a sequential chemical extraction procedure. Data from batch leaching tests and groundwater upstream and downstream of the waste deposits were also interpreted. The sequential extraction revealed that metals in <2 mm soil/waste samples were largely associated with geochemically active fractions, indicating that metals are released from pristine glass and subsequently largely retained in the surrounding soil and/or on secondary mineral coatings on fine glass particles. From the approximately 12,000 m(3) of coarse glass waste at the site, almost 4000 kg of Pb is estimated to have been lost through corrosion, which, however, corresponds to only a small portion of the total amount of Pb in the waste. Metal sorption within the waste deposits or in underlying soil layers is supported by fairly low metal concentrations in groundwater. However, elevated concentrations in downstream groundwater and in leachates of batch leaching tests were observed for several metals, indicating on-going leaching. Taken together, the high metal concentrations in geochemically active forms and the high amounts of as yet uncorroded metal-rich glass, indicate considerable risks to human health and the environment. Copyright © 2016. Published by Elsevier Ltd.

Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

NASA Astrophysics Data System (ADS)

Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.; Kruger, Albert A.

2017-11-01

The effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr)2O4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/or small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. The accumulation rate of ∼53.8 ± 3.7 μm/h determined for this glass will result in a ∼26 mm-thick layer after 20 days of melter idling.

Phosphate glasses for radioactive, hazardous and mixed waste immobilization

DOEpatents

Cao, H.; Adams, J.W.; Kalb, P.D.

1998-11-24

Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900 C include mixtures from about 1--6 mole % iron (III) oxide, from about 1--6 mole % aluminum oxide, from about 15--20 mole % sodium oxide or potassium oxide, and from about 30--60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400 C to about 450 C and which includes from about 3--6 mole % sodium oxide, from about 20--50 mole % tin oxide, from about 30--70 mole % phosphate, from about 3--6 mole % aluminum oxide, from about 3--8 mole % silicon oxide, from about 0.5--2 mole % iron (III) oxide and from about 3--6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided. 8 figs.

Corrosion Behavior and Microstructure Influence of Glass-Ceramic Nuclear Waste Forms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthew Asmussen, R.; Neeway, James J.; Kaspar, Tiffany C.

Glass ceramic waste forms present a potentially viable technology for the long term immobilization and disposal of liquid nuclear wastes. Through control of chemistry during fabrication, such waste forms can have designed secondary crystalline phases within a borosilicate glass matrix. In this work, a glass ceramic containing powellite and oxyapatite secondary phases was tested for its corrosion properties in dilute conditions using single pass flow through testing (SPFT). Three glass ceramic samples were prepared using different cooling rates to produce samples with varying microstructure sizes. In testing at 90 °C in buffered pH 7 and pH 9 solutions, it wasmore » found that increasing pH and decreasing microstructure size (resulting from rapid cooling during fabrication) both led to a reduction in overall corrosion rate. The phases of the glass ceramic were found, using a combination of solutions analysis, SEM and AFM, to corrode preferably in the order of powellite > bulk glass matrix > oxyapatite.« less

ADVANCED NUCLEAR FUEL CYCLE EFFECTS ON THE TREATMENT OF UNCERTAINTY IN THE LONG-TERM ASSESSMENT OF GEOLOGIC DISPOSAL SYSTEMS - EBS INPUT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sutton, M; Blink, J A; Greenberg, H R

2012-04-25

The Used Fuel Disposition (UFD) Campaign within the Department of Energy's Office of Nuclear Energy (DOE-NE) Fuel Cycle Technology (FCT) program has been tasked with investigating the disposal of the nation's spent nuclear fuel (SNF) and high-level nuclear waste (HLW) for a range of potential waste forms and geologic environments. The planning, construction, and operation of a nuclear disposal facility is a long-term process that involves engineered barriers that are tailored to both the geologic environment and the waste forms being emplaced. The UFD Campaign is considering a range of fuel cycles that in turn produce a range of wastemore » forms. The UFD Campaign is also considering a range of geologic media. These ranges could be thought of as adding uncertainty to what the disposal facility design will ultimately be; however, it may be preferable to thinking about the ranges as adding flexibility to design of a disposal facility. For example, as the overall DOE-NE program and industrial actions result in the fuel cycles that will produce waste to be disposed, and the characteristics of those wastes become clear, the disposal program retains flexibility in both the choice of geologic environment and the specific repository design. Of course, other factors also play a major role, including local and State-level acceptance of the specific site that provides the geologic environment. In contrast, the Yucca Mountain Project (YMP) repository license application (LA) is based on waste forms from an open fuel cycle (PWR and BWR assemblies from an open fuel cycle). These waste forms were about 90% of the total waste, and they were the determining waste form in developing the engineered barrier system (EBS) design for the Yucca Mountain Repository design. About 10% of the repository capacity was reserved for waste from a full recycle fuel cycle in which some actinides were extracted for weapons use, and the remaining fission products and some minor actinides were encapsulated in borosilicate glass. Because the heat load of the glass was much less than the PWR and BWR assemblies, the glass waste form was able to be co-disposed with the open cycle waste, by interspersing glass waste packages among the spent fuel assembly waste packages. In addition, the Yucca Mountain repository was designed to include some research reactor spent fuel and naval reactor spent fuel, within the envelope that was set using the commercial reactor assemblies as the design basis waste form. This milestone report supports Sandia National Laboratory milestone M2FT-12SN0814052, and is intended to be a chapter in that milestone report. The independent technical review of this LLNL milestone was performed at LLNL and is documented in the electronic Information Management (IM) system at LLNL. The objective of this work is to investigate what aspects of quantifying, characterizing, and representing the uncertainty associated with the engineered barrier are affected by implementing different advanced nuclear fuel cycles (e.g., partitioning and transmutation scenarios) together with corresponding designs and thermal constraints.« less

Hydrogen speciation in hydrated layers on nuclear waste glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aines, R.D.; Weed, H.C.; Bates, J.K.

1987-12-31

The hydration of an outer layer on nuclear waste glasses in known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. In addition, molecular watermore » was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. The hydrated layer on the nuclear waste glasses appears to be of relatively low water content (4 to 7% by weight) and is not substantially hydroxylated. Thus, these layers do not have many of the properties associated with gel layers.« less

Formulation of portland composite cement using waste glass as a supplementary cementitious material

NASA Astrophysics Data System (ADS)

Manullang, Ria Julyana; Samadhi, Tjokorde Walmiki; Purbasari, Aprilina

2017-09-01

Utilization of waste glass in cement is an attractive options because of its pozzolanic behaviour and the market of glass-composite cement is potentially available. The objective of this research is to evaluate the formulation of waste glass as supplementary cementitious material (SCM) by an extreme vertices mixture experiment, in which clinker, waste glass and gypsum proportions are chosen as experimental variables. The composite cements were synthesized by mixing all of powder materials in jar mill. The compressive strength of the composite cement mortars after being cured for 28 days ranges between 229 to 268 kg/cm2. Composite cement mortars exhibit lower compressive strength than ordinary Portland cement (OPC) mortars but is still capable of meeting the SNI 15-7064-2004 standards. The highest compressive strength is obtained by shifting the cement blend composition to the direction of increasing clinker and gypsum proportions as well as reducing glass proportion. The lower compressive strength of composite cement is caused by expansion due to ettringite and ASR gel. Based on the experimental result, the composite cement containing 80% clinker, 15% glass and 5% gypsum has the highest compressive strength. As such, the preliminary technical feasibility of reuse of waste glass as SCM has been confirmed.

Turning nuclear waste into glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pegg, Ian L.

2015-02-15

Vitrification has emerged as the treatment option of choice for the most dangerous radioactive waste. But dealing with the nuclear waste legacy of the Cold War will require state-of-the-art facilities and advanced glass formulations.

The quality study of recycled glass phosphor waste for LED

NASA Astrophysics Data System (ADS)

Tsai, Chun-Chin; Chen, Guan-Hao; Yue, Cheng-Feng; Chen, Cin-Fu; Cheng, Wood-Hi

2017-02-01

To study the feasibility and quality of recycled glass phosphor waste for LED packaging, the experiments were conducted to compare optical characteristics between fresh color conversion layer and that made of recycled waste. The fresh color conversion layer was fabricated through sintering pristine mixture of Y.A.G. powder [yellow phosphor (Y3AlO12 : Ce3+). Those recycled waste glass phosphor re-melted to form Secondary Molten Glass Phosphor (S.M.G.P.). The experiments on such low melting temperature glass results showed that transmission rates of S.M.G.P. are 9% higher than those of first-sintered glass phosphor, corresponding to 1.25% greater average bubble size and 36% more bubble coverage area in S.M.G.P. In the recent years, high power LED modules and laser projectors have been requiring higher thermal stability by using glass phosphor materials for light mixing. Nevertheless, phosphor and related materials are too expensive to expand their markets. It seems a right trend and research goal that recycling such waste of high thermal stability and quality materials could be preferably one of feasible cost-down solutions. This technical approach could bring out brighter future for solid lighting and light source module industries.

Vitrification of waste

DOEpatents

Wicks, G.G.

1999-04-06

A method is described for encapsulating and immobilizing waste for disposal. Waste, preferably, biologically, chemically and radioactively hazardous, and especially electronic wastes, such as circuit boards, are placed in a crucible and heated by microwaves to a temperature in the range of approximately 300 C to 800 C to incinerate organic materials, then heated further to a temperature in the range of approximately 1100 C to 1400 C at which temperature glass formers present in the waste will cause it to vitrify. Glass formers, such as borosilicate glass, quartz or fiberglass can be added at the start of the process to increase the silicate concentration sufficiently for vitrification.

Separating and stabilizing phosphate from high-level radioactive waste: process development and spectroscopic monitoring.

PubMed

Lumetta, Gregg J; Braley, Jenifer C; Peterson, James M; Bryan, Samuel A; Levitskaia, Tatiana G

2012-06-05

Removing phosphate from alkaline high-level waste sludges at the Department of Energy's Hanford Site in Washington State is necessary to increase the waste loading in the borosilicate glass waste form that will be used to immobilize the highly radioactive fraction of these wastes. We are developing a process which first leaches phosphate from the high-level waste solids with aqueous sodium hydroxide, and then isolates the phosphate by precipitation with calcium oxide. Tests with actual tank waste confirmed that this process is an effective method of phosphate removal from the sludge and offers an additional option for managing the phosphorus in the Hanford tank waste solids. The presence of vibrationally active species, such as nitrate and phosphate ions, in the tank waste processing streams makes the phosphate removal process an ideal candidate for monitoring by Raman or infrared spectroscopic means. As a proof-of-principle demonstration, Raman and Fourier transform infrared (FTIR) spectra were acquired for all phases during a test of the process with actual tank waste. Quantitative determination of phosphate, nitrate, and sulfate in the liquid phases was achieved by Raman spectroscopy, demonstrating the applicability of Raman spectroscopy for the monitoring of these species in the tank waste process streams.

Anaerobic co-digestion of sewage sludge and food waste.

PubMed

Prabhu, Meghanath S; Mutnuri, Srikanth

2016-04-01

Anaerobic co-digestion of organic matter improves digester operating characteristics and its performance. In the present work, food waste was collected from the institute cafeteria. Two types of sludge (before centrifuge and after centrifuge) were collected from the fluidised bed reactor of the institute treating sewage wastewater. Food waste and sludge were studied for their physico-chemical characteristics, such as pH, chemical oxygen demand, total solids, volatile solids, ammoniacal nitrogen, and total nitrogen. A biomethane potential assay was carried out to find out the optimum mixing ratio of food waste and sludge for anaerobic co-digestion. Results indicated that food waste mixed with sludge in the ratio of 1:2 produced the maximum biogas of 823 ml gVS(-1)(21 days) with an average methane content of 60%. Batch studies were conducted in 5 L lab-glass reactors at a mesophilic temperature. The effect of different substrate loading rates on biogas production was investigated. The mixing ratio of food waste and sludge was 1:2. A loading rate of 1 gVS L d(-1)gave the maximum biogas production of 742 ml g(-1)VS L d(-1)with a methane content of 50%, followed by 2 gVS L d(-1)with biogas of 539 ml g(-1)VS L d(-1) Microbial diversity of the reactor during fed batch studies was investigated by terminal restriction fragment length polymorphism. A pilot-scale co-digestion of food waste and sludge (before centrifuge) indicated the process stability of anaerobic digestion. © The Author(s) 2016.

Use of waste glass in highway construction (update--1992).

DOT National Transportation Integrated Search

1993-01-01

Increasing pressures to recycle more wastes and minimize the amount of materials placed in landfills are forcing reconsideration of potential uses of waste glass in highway construction and maintenance operations. The federal government and many stat...

Effects of waste glass and waste foundry sand additions on reclaimed tiles containing sewage sludge ash.

PubMed

Lin, Deng-Fong; Luo, Huan-Lin; Lin, Kuo-Liang; Liu, Zhe-Kun

2017-07-01

Applying sewage sludge ash (SSA) to produce reclaimed tiles is a promising recycling technology in resolving the increasing sludge wastes from wastewater treatment. However, performance of such reclaimed tiles is inferior to that of original ceramic tiles. Many researchers have therefore tried adding various industrial by-products to improve reclaimed tile properties. In this study, multiple materials including waste glass and waste foundry sand (WFS) were added in an attempt to improve physical and mechanical properties of reclaimed tiles with SSA. Samples with various combinations of clay, WFS, waste glass and SSA were made with three kiln temperatures of 1000°C, 1050°C, and 1100°C. A series of tests on the samples were next conducted. Test results showed that waste glass had positive effects on bending strength, water absorption and weight loss on ignition, while WFS contributed the most in reducing shrinkage, but could decrease the tile bending strength when large amount was added at a high kiln temperature. This study suggested that a combination of WFS from 10% to 15%, waste glass from 15% to 20%, SSA at 10% at a kiln temperature between 1000°C and 1050°C could result in quality reclaimed tiles with a balanced performance.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heitkamp, M.A.; Adams, W.J.; Camel, V.

Immobilized bacteria technology (IBT) utilizes inert biocarriers to support high concentrations of chemical-degrading bacteria in reactors designed to provide optimal conditions for microbial activity. This study evaluated IBT performance inpacked bed reactors (PBRs) using a porous inorganic biocarrier (diatomaceous earth), nonporous biocarriers (glass beads), and organic biocarriers having carbon adsorption properties (granular activated carbon) with different porosity. Each reactor was challenged with high chemical loading, acid, dryness, and heat shock conditions. Benchtop PBSs inoculated with a p-nitrophenol (PNP)-degrading Pseudomonas sp. and fed a synthetic waste containing 100 to 1,300 mg/L of PNP showed removal of PNP from effluents within 24more » h of start-up. Chemical loading studies showed maximum PNP removal rates of 6.45 to 7.35 kg/m[sup 3]/d for bacteria in PBRs containing diatomaceous earth beads, glass beads, and activated coconut carbon. A lower PNP removal rate of 1.47 kg/m[sup 3]/d was determined for the activated anthracite carbon, and this PBR responded more slowly to increases in chemical loading. The PBR containing bacteria immobilized on activated coconut carbon showed exceptional tolerance to acid shocking, drying, and heat shocking by maintaining PNP removal rates > 85% throughout the entire study. The other biocarriers showed nearly complete loss of PNP degradation during the perturbations, but all recovered high rates of PNP degradation (> 98% removal) within 48 h after an acid shock at pH2, within 8 d after an acid shock at pH 1.0, within 24 h after drying for 72 h, and within 48 h of heat shocking. The resiliency and high chemical removal efficiency demonstrated by immobilized bacteria in this study support the concept of using IBT for the biotreatment of industrial wastes..« less

Acid-Alkali Resistance of New Reclaimed Tiles Containing Sewage Sludge Ash and Waste Glass

PubMed Central

Lin, Deng-Fong; Lin, Kuo-Liang; Luo, Huan-Lin; Xu, Jia-Qin

2016-01-01

In this study, properties of newly developed reclaimed tiles in a harmful environment were investigated. A portion of clay used to manufacture tiles was replaced with sewage sludge ash (SSA) and waste glass to produce the new reclaimed tiles. To investigate the effects of SSA and waste glass on the properties of the tiles, different specimens were blended and placed in acid-alkali solutions. The reclaimed tile specimens were manufactured by clay, 10% SSA, and five different mixes of waste glass replacement, namely, 0%, 10%, 20%, 40%, and 60%. These specimens were calcined at 1000 °C and subsequently underwent a series of tests, including TGA/DTA (thermogravimetric analysis/differential thermal analysis), SEM (scanning electron microscopy), XRD (X-ray diffraction), bending strength, weight loss, and porosity. Test results show that shortcomings associated with the introduction of the sludge ash were improved by the admixture of waste glass, especially in the aspects of shrinkage and bending strength. The study showed that the new reclaimed tiles performed relatively well in acid-alkali resistance tests but appeared to have better alkali resistance than acid resistance. It was also found that the optimal mix of such reclaimed tiles was 10% SSA, 10% waste glass, and 80% clay. PMID:28773668

Waste form evaluation for RECl 3 and REO x fission products separated from used electrochemical salt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Pierce, David A.; Crum, Jarrod V.

The work presented here is based off the concept that the rare earth chloride (RECl 3) fission products within the used electrorefiner (ER) salt can be selectively removed as RECl 3 (not yet demonstrated) or precipitated out as a mixture of REOCl and REO x through oxygen sparging (has been demonstrated). This paper presents data showing the feasibility of immobilizing a mixture of RECl 3s at 10 mass% into a 78%TeO 2-22%PbO glass while also showing that this same mixture of RECl 3s can be oxidized to REOCl at 300 °C and then to REO x by 1200 °C, evolvingmore » Cl 2(g). When the REO x mixture is heated at temperatures >1200 °C, the ratios of REO xs change. The mixture of REO x was then immobilized in a lanthanide borosilicate (LABS) glass at a high loading of 60 mass%. Both the 78%TeO 2-22%PbO glass and LABS glass systems show good chemical durability. In conclusion, the advantages and disadvantages of tellurite and LABS glasses are compared.« less

Waste form evaluation for RECl 3 and REO x fission products separated from used electrochemical salt

DOE PAGES

Riley, Brian J.; Pierce, David A.; Crum, Jarrod V.; ...

2017-09-22

The work presented here is based off the concept that the rare earth chloride (RECl 3) fission products within the used electrorefiner (ER) salt can be selectively removed as RECl 3 (not yet demonstrated) or precipitated out as a mixture of REOCl and REO x through oxygen sparging (has been demonstrated). This paper presents data showing the feasibility of immobilizing a mixture of RECl 3s at 10 mass% into a 78%TeO 2-22%PbO glass while also showing that this same mixture of RECl 3s can be oxidized to REOCl at 300 °C and then to REO x by 1200 °C, evolvingmore » Cl 2(g). When the REO x mixture is heated at temperatures >1200 °C, the ratios of REO xs change. The mixture of REO x was then immobilized in a lanthanide borosilicate (LABS) glass at a high loading of 60 mass%. Both the 78%TeO 2-22%PbO glass and LABS glass systems show good chemical durability. In conclusion, the advantages and disadvantages of tellurite and LABS glasses are compared.« less

Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.

We present that the effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr) 2O 4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/ormore » small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. In conclusion, the accumulation rate of ~53.8 ± 3.7 μm/h determined for this glass will result in a ~26 mm-thick layer after 20 days of melter idling.« less

Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

DOE PAGES

Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.; ...

2017-08-30

We present that the effectiveness of high-level waste vitrification at Hanford's Waste Treatment and Immobilization Plant may be limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr) 2O 4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layers, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/ormore » small-scale agglomerates, but excessive agglomeration observed in high-Ni-Fe glass resulted in an underprediction of accumulated layers, which gradually worsened over time as an increased number of agglomerates formed. In conclusion, the accumulation rate of ~53.8 ± 3.7 μm/h determined for this glass will result in a ~26 mm-thick layer after 20 days of melter idling.« less

Vitrification of waste

DOEpatents

Wicks, George G.

1999-01-01

A method for encapsulating and immobilizing waste for disposal. Waste, preferably, biologically, chemically and radioactively hazardous, and especially electronic wastes, such as circuit boards, are placed in a crucible and heated by microwaves to a temperature in the range of approximately 300.degree. C. to 800.degree. C. to incinerate organic materials, then heated further to a temperature in the range of approximately 1100.degree. C. to 1400.degree. C. at which temperature glass formers present in the waste will cause it to vitrify. Glass formers, such as borosilicate glass, quartz or fiberglass can be added at the start of the process to increase the silicate concentration sufficiently for vitrification.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Edwards, T. B.; Riley, W. T.

In this report, the Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for several simulated low activity waste (LAW) glasses (designated as the January, March, and April 2015 LAW glasses) fabricated by the Pacific Northwest National Laboratory. The results of these analyses will be used as part of efforts to revise or extend the validation regions of the current Hanford Waste Treatment and Immobilization Plant glass property models to cover a broader span of waste compositions.

A hazardous waste from secondary aluminium metallurgy as a new raw material for calcium aluminate glasses.

PubMed

López-Delgado, Aurora; Tayibi, Hanan; Pérez, Carlos; Alguacil, Francisco José; López, Félix Antonio

2009-06-15

A solid waste coming from the secondary aluminium industry was successfully vitrified in the ternary CaO-Al(2)O(3)-SiO(2) system at 1500 degrees C. This waste is a complex material which is considered hazardous because of its behaviour in the presence of water or moisture. In these conditions, the dust can generate gases such as H(2), NH(3), CH(4), H(2)S, along with heat and potential aluminothermy. Only silica sand and calcium carbonate were added as external raw materials to complete the glasses formula. Different nominal compositions of glasses, with Al(2)O(3) ranging between 20% and 54%, were studied to determine the glass forming area. The glasses obtained allow the immobilisation of up to 75% of waste in a multicomponent oxide system in which all the components of the waste are incorporated. The microhardness Hv values varied between 6.05 and 6.62GPa and the linear thermal expansion coefficient, alpha, varied between (62 and 139)x10(-7)K(-1). Several glasses showed a high hydrolytic resistance in deionised water at 98 degrees C.

Glass composite waste forms for iodine confined in bismuth-embedded SBA-15

NASA Astrophysics Data System (ADS)

Yang, Jae Hwan; Park, Hwan Seo; Ahn, Do-Hee; Yim, Man-Sung

2016-11-01

The aim of this study was to stabilize bismuth-embedded SBA-15 that captured iodine gas by fabrication of monolithic waste forms. The iodine containing waste was mixed with Bi2O3 (a stabilizing additive) and low-temperature sintering glass followed by pelletizing and the sintering process to produce glass composite materials. Iodine volatility during the sintering process was significantly affected by the ratio of Bi2O3 and the glass composition. It was confirmed that BiI3, the main iodine phase within bismuth-embedded SBA-15, was effectively transformed to the mixed phases of Bi5O7I and BiOI. The initial leaching rates of iodine from the glass composite waste forms ranged 10-3-10-2 g/m2 day, showing the stability of the iodine phases encapsulated by the glassy networks. It was also observed that common groundwater anions (e.g., chloride, carbonate, sulfite, and fluoride) elevated the iodine leaching rate by anion exchange reactions. The present results suggest that the glass composite waste form of bismuth-embedded SBA-15 could be a candidate material for stable storage of 129I.

Glasses for immobilization of low- and intermediate-level radioactive waste

NASA Astrophysics Data System (ADS)

Laverov, N. P.; Omel'yanenko, B. I.; Yudintsev, S. V.; Stefanovsky, S. V.; Nikonov, B. S.

2013-03-01

Reprocessing of spent nuclear fuel (SNF) for recovery of fissionable elements is a precondition of long-term development of nuclear energetics. Solution of this problem is hindered by the production of a great amount of liquid waste; 99% of its volume is low- and intermediate-level radioactive waste (LILW). The volume of high-level radioactive waste (HLW), which is characterized by high heat release, does not exceed a fraction of a percent. Solubility of glasses at an elevated temperature makes them unfit for immobilization of HLW, the insulation of which is ensured only by mineral-like matrices. At the same time, glasses are a perfect matrix for LILW, which are distinguished by low heat release. The solubility of borosilicate glass at a low temperature is so low that even a glass with relatively low resistance enables them to retain safety of under-ground LILW depositories without additional engineering barriers. The optimal technology of liquid confinement is their concentration and immobilization in borosilicate glasses, which are disposed in shallow-seated geological repositories. The vitrification of 1 m3 liquid LILW with a salt concentration of ˜300 kg/m3 leaves behind only 0.2 m3 waste, that is, 4-6 times less than by bitumen impregnation and 10 times less than by cementation. Environmental and economic advantages of LILW vitrification result from (1) low solubility of the vitrified LILW in natural water; (2) significant reduction of LILW volume; (3) possibility to dispose the vitrified waste without additional engineering barriers under shallow conditions and in diverse geological media; (4) the strength of glass makes its transportation and storage possible; and finally (5) reliable longterm safety of repositories. When the composition of the glass matrix for LILW is being chosen, attention should be paid to the factors that ensure high technological and economic efficiency of vitrification. The study of vitrified LILW from the Kursk nuclear power plant with high-power channel reactors (HPCR; equivalent Russian acronym, RBMK) and the Kalinin nuclear power plant with pressurized water reactors (PWR; equivalent Russian acronym VVER) after their 14-yr storage in the shallow-seated repository at the MosNPO Radon testing ground has confirmed the safety of repositories ensured by confinement properties of borosilicate matrix. The most efficient vitrification technology is based on cold crucible induction melting. If the content of a chemical element in waste exceeds its solubility in glass, a crystalline phase is formed in the course of vitrification, so that the glass ceramics become a matrix for such waste. Vitrified waste with high Fe; Na and Al; Na, Fe, and Al; Na and B is characterized. The composition of frit and its proportion to waste depends on waste composition. This procedure requires careful laboratory testing.

Summary Report For The Analysis Of The Sludge Batch 7b (Macrobatch 9) DWPF Pour Stream Glass Sample For Canister S04023

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, F. C.

2013-11-18

In order to comply with the Defense Waste Processing Facility (DWPF) Waste Form Compliance Plan for Sluldge Batch 7b, Savannah River National Laboratory (SRNL) personnel characterized the Defense Waste Processing Facility (DWPF) pour stream (PS) glass sample collected while filling canister S04023. This report summarizes the results of the compositional analysis for reportable oxides and radionuclides and the normalized Product Consistency Test (PCT) results. The PCT responses indicate that the DWPF produced glass that is significantly more durable than the Environmental Assessment glass.

Vitrification of organics-containing wastes

DOEpatents

Bickford, D.F.

1995-01-01

A process for stabilizing organics-containing waste materials and recovery metals therefrom, and a waste glass product made according to the process are described. Vitrification of wastes such as organic ion exchange resins, electronic components and the like can be accomplished by mixing at least one transition metal oxide with the wastes, and, if needed, glass formers to compensate for a shortage of silicates or other glass formers in the wastes. The transition metal oxide increases the rate of oxidation of organic materials in the wastes to improve the composition of the glass-forming mixture: at low temperatures, the oxide catalyzes oxidation of a portion of the organics in the waste; at higher temperatures, the oxide dissolves and the resulting oxygen ions oxidize more of the organics; and at vitrification temperatures, the metal ions conduct oxygen into the melt to oxidize the remaining organics. In addition, the transition metal oxide buffers the redox potential of the glass melt so that metals such as Au, Pt, Ag, and Cu separate form the melt in the metallic state and can be recovered. After the metals are recovered, the remainder of the melt is allowed to cool and may subsequently be disposed of. The product has good leaching resistance and can be disposed of in an ordinary landfill, or, alternatively, used as a filler in materials such as concrete, asphalt, brick and tile.

Vitrification of organics-containing wastes

DOEpatents

Bickford, Dennis F.

1997-01-01

A process for stabilizing organics-containing waste materials and recovering metals therefrom, and a waste glass product made according to the process. Vitrification of wastes such as organic ion exchange resins, electronic components and the like can be accomplished by mixing at least one transition metal oxide with the wastes, and, if needed, glass formers to compensate for a shortage of silicates or other glass formers in the wastes. The transition metal oxide increases the rate of oxidation of organic materials in the wastes to improve the composition of the glass-forming mixture: at low temperatures, the oxide catalyzes oxidation of a portion of the organics in the waste; at higher temperatures, the oxide dissolves and the resulting oxygen ions oxidize more of the organics; and at vitrification temperatures, the metal ions conduct oxygen into the melt to oxidize the remaining organics. In addition, the transition metal oxide buffers the redox potential of the glass melt so that metals such as Au, Pt, Ag, and Cu separate from the melt in the metallic state and can be recovered. After the metals are recovered, the remainder of the melt is allowed to cool and may subsequently be disposed of. The product has good leaching resistance and can be disposed of in an ordinary landfill, or, alternatively, used as a filler in materials such as concrete, asphalt, brick and tile.

Vitrification of organics-containing wastes

DOEpatents

Bickford, D.F.

1997-09-02

A process is described for stabilizing organics-containing waste materials and recovering metals therefrom, and a waste glass product made according to the process is also disclosed. Vitrification of wastes such as organic ion exchange resins, electronic components and the like can be accomplished by mixing at least one transition metal oxide with the wastes, and, if needed, glass formers to compensate for a shortage of silicates or other glass formers in the wastes. The transition metal oxide increases the rate of oxidation of organic materials in the wastes to improve the composition of the glass-forming mixture: at low temperatures, the oxide catalyzes oxidation of a portion of the organics in the waste; at higher temperatures, the oxide dissolves and the resulting oxygen ions oxidize more of the organics; and at vitrification temperatures, the metal ions conduct oxygen into the melt to oxidize the remaining organics. In addition, the transition metal oxide buffers the redox potential of the glass melt so that metals such as Au, Pt, Ag, and Cu separate from the melt in the metallic state and can be recovered. After the metals are recovered, the remainder of the melt is allowed to cool and may subsequently be disposed of. The product has good leaching resistance and can be disposed of in an ordinary landfill, or, alternatively, used as a filler in materials such as concrete, asphalt, brick and tile. 1 fig.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, John D.; Todd, Terry A.; Gray, Kimberly D.

The U.S. Department of Energy, Office of Nuclear Energy has chartered an effort to develop technologies to enable safe and cost effective recycle of commercial used nuclear fuel (UNF) in the U.S. Part of this effort includes the evaluation of exiting waste management technologies for effective treatment of wastes in the context of current U.S. regulations and development of waste forms and processes with significant cost and/or performance benefits over those existing. This study summarizes the results of these ongoing efforts with a focus on the highly radioactive primary waste streams. The primary streams considered and the recommended waste formsmore » include: •Tritium separated from either a low volume gas stream or a high volume water stream. The recommended waste form is low-water cement in high integrity containers. •Iodine-129 separated from off-gas streams in aqueous processing. There are a range of potentially suitable waste forms. As a reference case, a glass composite material (GCM) formed by the encapsulation of the silver Mordenite (AgZ) getter material in a low-temperature glass is assumed. A number of alternatives with distinct advantages are also considered including a fused silica waste form with encapsulated nano-sized AgI crystals. •Carbon-14 separated from LWR fuel treatment off-gases and immobilized as a CaCO3 in a cement waste form. •Krypton-85 separated from LWR and SFR fuel treatment off-gases and stored as a compressed gas. •An aqueous reprocessing high-level waste (HLW) raffinate waste which is immobilized by the vitrification process in one of three forms: a single phase borosilicate glass, a borosilicate based glass ceramic, or a multi-phased titanate ceramic [e.g., synthetic rock (Synroc)]. •An undissolved solids (UDS) fraction from aqueous reprocessing of LWR fuel that is either included in the borosilicate HLW glass or is immobilized in the form of a metal alloy in the case of glass ceramics or titanate ceramics. •Zirconium-based LWR fuel cladding hulls and stainless steel (SS) fuel assembly hardware that are washed and super-compacted for disposal or as an alternative Zr purification and reuse (or disposal as low-level waste, LLW) by reactive gas separations. •Electrochemical process salt HLW which is immobilized in a glass bonded Sodalite waste form known as the ceramic waste form (CWF). •Electrochemical process UDS and SS cladding hulls which are melted into an iron based alloy waste form. Mass and volume estimates for each of the recommended waste forms based on the source terms from a representative flowsheet are reported.« less

Corrosion resistance of ceramic refractories to simulated waste glasses at high temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xing, S.B.; Lin, Y.; Mohr, R.K.

1996-08-01

In many vitrification processes, refractory materials are used to contain the waste glass melt. The corrosive nature of the high-temperature melt consumes the waste feed materials but also limits refractory life. As vitrification is applied to more diverse waste streams, and particularly in higher-temperature applications, increasingly severe demands are placed on the refractory materials. A variety of potential refractory materials including Fused-cast AZS, Monofrax K3, Monofrax E, and the Corhart refractories ER1195, ER2161, C1215, C1215Z, Rechrome, and T1186, were subjected to corrosion testing at 1,450 C using the ASTM C-621 procedure. A series of simulated waste glasses was used whichmore » included F, Cl, S, Cu, Zn, Pb; these minor components were found to cause significant, and in some cases drastic, increases in corrosion rates. The corrosion tests were conducted over a range of time intervals extending to 144 hrs in order to investigate the kinetics of the corrosion processes. The change of the concentrations of constituents in the glass was monitored by compositional analysis of glass samples and correlated to the observed extent of corrosion; typically, components of the material under test increase with time while key minor components, such as Co and Pb, decrease. The rate of corrosion of high-zirconia refractories was slowed considerably by adding zirconia to the waste glass composition; this has the added benefit of improving the aqueous leach resistance of the waste form that is produced.« less

Recycling of inorganic waste in monolithic and cellular glass‐based materials for structural and functional applications

PubMed Central

Rincón, Acacio; Marangoni, Mauro; Cetin, Suna

2016-01-01

Abstract The stabilization of inorganic waste of various nature and origin, in glasses, has been a key strategy for environmental protection for the last decades. When properly formulated, glasses may retain many inorganic contaminants permanently, but it must be acknowledged that some criticism remains, mainly concerning costs and energy use. As a consequence, the sustainability of vitrification largely relies on the conversion of waste glasses into new, usable and marketable glass‐based materials, in the form of monolithic and cellular glass‐ceramics. The effective conversion in turn depends on the simultaneous control of both starting materials and manufacturing processes. While silica‐rich waste favours the obtainment of glass, iron‐rich wastes affect the functionalities, influencing the porosity in cellular glass‐based materials as well as catalytic, magnetic, optical and electrical properties. Engineered formulations may lead to important reductions of processing times and temperatures, in the transformation of waste‐derived glasses into glass‐ceramics, or even bring interesting shortcuts. Direct sintering of wastes, combined with recycled glasses, as an example, has been proven as a valid low‐cost alternative for glass‐ceramic manufacturing, for wastes with limited hazardousness. The present paper is aimed at providing an up‐to‐date overview of the correlation between formulations, manufacturing technologies and properties of most recent waste‐derived, glass‐based materials. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:27818564

Plutonium immobilization in glass and ceramics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knecht, D.A.; Murphy, W.M.

1996-05-01

The Materials Research Society Nineteenth Annual Symposium on the Scientific Basis for Nuclear Waste Management was held in Boston on November 27 to December 1, 1995. Over 150 papers were presented at the Symposium dealing with all aspects of nuclear waste management and disposal. Fourteen oral sessions and on poster session included a Plenary session on surplus plutonium dispositioning and waste forms. The proceedings, to be published in April, 1996, will provide a highly respected, referred compilation of the state of scientific development in the field of nuclear waste management. This paper provides a brief overview of the selected Symposiummore » papers that are applicable to plutonium immobilization and plutonium waste form performance. Waste forms that were described at the Symposium cover most of the candidate Pu immobilization options under consideration, including borosilicate glass with a melting temperature of 1150 {degrees}C, a higher temperature (1450 {degrees}C) lanthanide glass, single phase ceramics, multi-phase ceramics, and multi-phase crystal-glass composites (glass-ceramics or slags). These Symposium papers selected for this overview provide the current status of the technology in these areas and give references to the relevant literature.« less

Synthesis of silica gel from waste glass bottles and its application for the reduction of free fatty acid (FFA) on waste cooking oil

NASA Astrophysics Data System (ADS)

Sudjarwo, Wisnu Arfian A.; Bee, Mei Magdayanti F.

2017-06-01

Synthesis of silica gel from waste glass bottles was conducted with aims to characterize the product and to analyze its application forthe reduction of free fatty acid (FFA) on waste cooking oil. Silica source taken from waste glass bottles was synthesized into silica gel by using the sol-gel method. Several types of silica gel were produced with three different weight ratios of waste glass and sodium hydroxide as an extractor. They were: 1:1, 1:2, and 1:3. The results indicated that synthesized silica possessed morphology innano-sizedranging from 85 nm to 459 nm. Adsorption performance was investigated by a batch system atthe temperature between 70°C and 110°C by a range of 10°C in an hour. Analysis of the adsorption characteristic showed that the highest efficiency value of FFA reduction of 91% was obtained by silica gel with ratiosof 1:1 (SG 1) and 1:3 (SG 3). Their performances were also followed by the decline of the refractive index and the density of waste cooking oil.

Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter: Summary of 2017 experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Fowley, M.

A full-scale, transparent mock-up of the Hanford Tank Waste Treatment and Immobilization Project High Level Waste glass melter riser and pour spout has been constructed to allow for testing with visual feedback of particle settling, accumulation, and resuspension when operating with a controlled fraction of crystals in the glass melt. Room temperature operation with silicone oil and magnetite particles simulating molten glass and spinel crystals, respectively, allows for direct observation of flow patterns and settling patterns. The fluid and particle mixture is recycled within the system for each test.

Sodalite as a vehicle to increase Re retention in waste glass simulant during vitrification

NASA Astrophysics Data System (ADS)

Luksic, Steven A.; Riley, Brian J.; Parker, Kent E.; Hrma, Pavel

2016-10-01

Technetium (Tc) retention during Hanford waste vitrification can be increased if the volatility can be controlled. Incorporating Tc into a thermally stable mineral phase, such as sodalite, is one way to achieve increased retention. Here, rhenium (Re)-bearing sodalite was tested as a vehicle to transport perrhenate (ReO4-), a nonradioactive surrogate for pertechnetate (TcO4-), into high-level (HLW) and low-activity waste (LAW) glass simulants. After melting HLW and LAW simulant feeds, the retention of Re in the glass was measured and compared with the Re retention in glass prepared from a feed containing Re2O7. Phase analysis of sodalite in both these glasses across a profile of temperatures describes the durability of Re-sodalite during the feed-to-glass transition. The use of Re sodalite improved the Re retention by 21% for HLW glass and 85% for LAW glass, demonstrating the potential improvement in Tc-retention if TcO4- were to be encapsulated in a Tc-sodalite prior to vitrification.

Low melting high lithia glass compositions and methods

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

2003-09-23

The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste uranium oxides The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

Kinetics of Cold-Cap Reactions for Vitrification of Nuclear Waste Glass Based on Simultaneous Differential Scanning Calorimetry - Thermogravimetry (DSC-TGA) and Evolved Gas Analysis (EGA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodriguez, Carmen P.; Pierce, David A.; Schweiger, Michael J.

2013-12-03

For vitrifying nuclear waste glass, the feed, a mixture of waste with glass-forming and modifying additives, is charged onto the cold cap that covers 90-100% of the melt surface. The cold cap consists of a layer of reacting molten glass floating on the surface of the melt in an all-electric, continuous glass melter. As the feed moves through the cold cap, it undergoes chemical reactions and phase transitions through which it is converted to molten glass that moves from the cold cap into the melt pool. The process involves a series of reactions that generate multiple gases and subsequent massmore » loss and foaming significantly influence the mass and heat transfers. The rate of glass melting, which is greatly influenced by mass and heat transfers, affects the vitrification process and the efficiency of the immobilization of nuclear waste. We studied the cold-cap reactions of a representative waste glass feed using both the simultaneous differential scanning calorimetry thermogravimetry (DSC-TGA) and the thermogravimetry coupled with gas chromatography-mass spectrometer (TGA-GC-MS) as complementary tools to perform evolved gas analysis (EGA). Analyses from DSC-TGA and EGA on the cold-cap reactions provide a key element for the development of an advanced cold-cap model. It also helps to formulate melter feeds for higher production rate.« less

Treatment of copper industry waste and production of sintered glass-ceramic.

PubMed

Coruh, Semra; Ergun, Osman Nuri; Cheng, Ta-Wui

2006-06-01

Copper waste is iron-rich hazardous waste containing heavy metals such as Cu, Zn, Co, Pb. The results of leaching tests show that the concentration of these elements exceeds the Turkish and EPA regulatory limits. Consequently, this waste cannot be disposed of in its present form and therefore requires treatment to stabilize it or make it inert prior to disposal. Vitrification was selected as the technology for the treatment of the toxic waste under investigation. During the vitrification process significant amounts of the toxic organic and inorganic chemical compounds could be destroyed, and at the same time, the metal species are immobilized as they become an integral part of the glass matrix. The copper flotation waste samples used in this research were obtained from the Black Sea Copper Works of Samsun, Turkey. The samples were vitrified after being mixed with other inorganic waste and materials. The copper flotation waste and their glass-ceramic products were characterized by X-ray analysis (XRD), scanning electron microscopy and by the toxicity characteristic leaching procedure test. The products showed very good chemical durability. The glass-ceramics fabricated at 850 degrees C/2 h have a large application potential especially as construction and building materials.

Environmental Assessment for the Operation of the Glass Melter Thermal Treatment Unit at the US Department of Energy`s Mound Plant, Miamisburg, Ohio

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-06-01

The glass melter would thermally treat mixed waste (hazardous waste contaminated with radioactive constituents largely tritium, Pu-238, and/or Th-230) that was generated at the Mound Plant and is now in storage, by stabilizing the waste in glass blocks. Depending on the radiation level of the waste, the glass melter may operate for 1 to 6 years. Two onsite alternatives and seven offsite alternatives were considered. This environmental assessment indicates that the proposed action does not constitute a major Federal action significantly affecting the human environment according to NEPA, and therefore the finding of no significant impact is made, obviating themore » need for an environmental impact statement.« less

Phosphate glasses for radioactive, hazardous and mixed waste immobilization

DOEpatents

Cao, H.; Adams, J.W.; Kalb, P.D.

1999-03-09

Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900 C include mixtures from about 1 mole % to about 6 mole % iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400 C to about 450 C and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided. 8 figs.

Phosphate glasses for radioactive, hazardous and mixed waste immobilization

DOEpatents

Cao, Hui; Adams, Jay W.; Kalb, Paul D.

1998-11-24

Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900.degree. C. include mixtures from about 1 mole % to about 6 mole % iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400.degree. C. to about 450.degree. C. and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided.

Phosphate glasses for radioactive, hazardous and mixed waste immobilization

DOEpatents

Cao, Hui; Adams, Jay W.; Kalb, Paul D.

1999-03-09

Lead-free phosphate glass compositions are provided which can be used to immobilize low level and/or high level radioactive wastes in monolithic waste forms. The glass composition may also be used without waste contained therein. Lead-free phosphate glass compositions prepared at about 900.degree. C. include mixtures from about 1 mole % to about 6 mole %.iron (III) oxide, from about 1 mole % to about 6 mole % aluminum oxide, from about 15 mole % to about 20 mole % sodium oxide or potassium oxide, and from about 30 mole % to about 60 mole % phosphate. The invention also provides phosphate, lead-free glass ceramic glass compositions which are prepared from about 400.degree. C. to about 450.degree. C. and which includes from about 3 mole % to about 6 mole % sodium oxide, from about 20 mole % to about 50 mole % tin oxide, from about 30 mole % to about 70 mole % phosphate, from about 3 mole % to about 6 mole % aluminum oxide, from about 3 mole % to about 8 mole % silicon oxide, from about 0.5 mole % to about 2 mole % iron (III) oxide and from about 3 mole % to about 6 mole % potassium oxide. Method of making lead-free phosphate glasses are also provided.

Influence of low concentration V and Co oxide doping on the dissolution behaviors of simplified nuclear waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Xiaonan; Neeway, James J.; Ryan, Joseph V.

Transition metal oxides are commonly present in nuclear waste and they can alter the structure, property and especially dissolution behaviors of the glasses used for waste immobilization. In this paper, we investigated vanadium and cobalt oxide induced structural and properties changes, especially dissolution behaviors, of International Simple Glass (ISG), a model nuclear waste glass system. Static chemical durability tests were performed at 90 °C with a pH value of 7 and a surface-area-to-solution-volume of 200 m-1 for 112 days on three glasses: ISG, ISG doped with 0.5 mol% Co2O3, and ISG doped with 2.0 mol% V2O5. ICP-MS was used tomore » analyze the dissolved ion concentrations. It was found that doping with vanadium and cobalt oxide, even at the low doping concentration, significantly reduced the extent of the ISG glass dissolution. Differential Scanning Calorimetry (DSC) analysis showed that vanadium oxide doping reduced the glass transition temperature (Tg) while cobalt oxide did not significantly change the Tg of ISG. X-ray diffraction (XRD), Raman spectrometry and scanning electron microscopy (SEM) were used to analyze the glass samples before and after corrosion to understand the phase and microstructure changes.« less

Rhenium solubility in borosilicate nuclear waste glass: implications for the processing and immobilization of technetium-99.

PubMed

McCloy, John S; Riley, Brian J; Goel, Ashutosh; Liezers, Martin; Schweiger, Michael J; Rodriguez, Carmen P; Hrma, Pavel; Kim, Dong-Sang; Lukens, Wayne W; Kruger, Albert A

2012-11-20

The immobilization of technetium-99 ((99)Tc) in a suitable host matrix has proven to be a challenging task for researchers in the nuclear waste community around the world. In this context, the present work reports on the solubility and retention of rhenium, a nonradioactive surrogate for (99)Tc, in a sodium borosilicate glass. Glasses containing target Re concentrations from 0 to 10,000 ppm [by mass, added as KReO(4) (Re(7+))] were synthesized in vacuum-sealed quartz ampules to minimize the loss of Re from volatilization during melting at 1000 °C. The rhenium was found as Re(7+) in all of the glasses as observed by X-ray absorption near-edge structure. The solubility of Re in borosilicate glasses was determined to be ~3000 ppm (by mass) using inductively coupled plasma optical emission spectroscopy. At higher rhenium concentrations, additional rhenium was retained in the glasses as crystalline inclusions of alkali perrhenates detected with X-ray diffraction. Since (99)Tc concentrations in a glass waste form are predicted to be <10 ppm (by mass), these Re results implied that the solubility should not be a limiting factor in processing radioactive wastes, assuming Tc as Tc(7+) and similarities between Re(7+) and Tc(7+) behavior in this glass system.

Process for solidifying high-level nuclear waste

DOEpatents

Ross, Wayne A.

1978-01-01

The addition of a small amount of reducing agent to a mixture of a high-level radioactive waste calcine and glass frit before the mixture is melted will produce a more homogeneous glass which is leach-resistant and suitable for long-term storage of high-level radioactive waste products.

Study on the Strength of GFRP/Stainless Steel Adhesive Joints Reinforced with Glass Mat

NASA Astrophysics Data System (ADS)

Iwasa, Masaaki

The adhesive strengths of glass fiber reinforced plastics/metal adhesive joints reinforced with glass mat under tensile shear loads and tensile loads were investigated analytically and experimentally. First, the stress singularity parameters of the bonding edges were analyzed by FEM for various types of adhesive joints reinforced with glass mat. The shear stress and normal stress distributions near the bonding edge can be expressed by two stress singularity parameters. Second, tensile shear tests were performed on taper lap joint and taper lap joint reinforced with glass mat and tensile tests were performed on T-type adhesive joint and T-type adhesive joint reinforced with glass mat. The relationships between the loads and the crosshead displacements were measured. We concluded that reinforcing adhesive joints has a greater effect on strength under tensile load than under tensile shear load. The adhesive joints strength reinforced with glass mat can be evaluated by using stress singularity parameters.

Recovery of fissile materials from nuclear wastes

DOEpatents

Forsberg, Charles W.

1999-01-01

A process for recovering fissile materials such as uranium, and plutonium, and rare earth elements, from complex waste feed material, and converting the remaining wastes into a waste glass suitable for storage or disposal. The waste feed is mixed with a dissolution glass formed of lead oxide and boron oxide resulting in oxidation, dehalogenation, and dissolution of metal oxides. Carbon is added to remove lead oxide, and a boron oxide fusion melt is produced. The fusion melt is essentially devoid of organic materials and halogens, and is easily and rapidly dissolved in nitric acid. After dissolution, uranium, plutonium and rare earth elements are separated from the acid and recovered by processes such as PUREX or ion exchange. The remaining acid waste stream is vitrified to produce a waste glass suitable for storage or disposal. Potential waste feed materials include plutonium scrap and residue, miscellaneous spent nuclear fuel, and uranium fissile wastes. The initial feed materials may contain mixtures of metals, ceramics, amorphous solids, halides, organic material and other carbon-containing material.

Glass corrosion in natural environments

NASA Technical Reports Server (NTRS)

Thorpe, Arthur N.; Barkatt, Aaron

1992-01-01

Experiments carried out during the progress period are summarized. Experiments carried out involving glass samples exposed to solutions of Tris have shown the appearance of 'spikes' upon monitoring glass dissolution as a function of time. The periodic 'spikes' observed in Tris-based media were interpreted in terms of cracking due to excessive stress in the surface region of the glass. Studies of the interactions of silicate glasses with metal ions in buffered media were extended to systems containing Al. Caps buffer was used to establish the pH. The procedures used are described and the results are given. Preliminary studies were initiated as to the feasibility of adding a slowly dissolving solid compound of the additive to the glass-water system to maintain a supply of dissolved additive. It appears that several magnesium compounds have a suitable combination of solubility and affinity towards silicate glass surfaces to have a pronounced retarding effect on the extraction of uranium from the glass. These preliminary findings raise the possibility that introducing a magnesium source into geologic repositories for nuclear waste glass in the form of a sparingly soluble Mg-based backfill material may cause a substantial reduction in the extent of long-term glass corrosion. The studies described also provide mechanistic understanding of the roles of various metal solutes in the leachant. Such understanding forms the basis for developing long-term predictions of nuclear waste glass durability under repository conditions. From what is known about natural highly reduced glasses such as tektites, it is clear that iron is dissolved as ferrous iron with little or no ferric iron. The reducing conditions were high enough to cause metallic iron to exsolve out of the glass in the form of submicroscopic spherules. As the nuclear waste glass is much less reduced, a study was initiated on other natural glasses in addition to the nuclear waste glass. Extensive measurements were carried out on these glasses in order to characterize their magnetic properties. Results of these studies are described.

Gaseous Sulfate Solubility in Glass: Experimental Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bliss, Mary

2013-11-30

Sulfate solubility in glass is a key parameter in many commercial glasses and nuclear waste glasses. This report summarizes key publications specific to sulfate solubility experimental methods and the underlying physical chemistry calculations. The published methods and experimental data are used to verify the calculations in this report and are expanded to a range of current technical interest. The calculations and experimental methods described in this report will guide several experiments on sulfate solubility and saturation for the Hanford Waste Treatment Plant Enhanced Waste Glass Models effort. There are several tables of sulfate gas equilibrium values at high temperature tomore » guide experimental gas mixing and to achieve desired SO3 levels. This report also describes the necessary equipment and best practices to perform sulfate saturation experiments for molten glasses. Results and findings will be published when experimental work is finished and this report is validated from the data obtained.« less

Dilute condition corrosion behavior of glass-ceramic waste form

DOE PAGES

Crum, Jarrod V.; Neeway, James J.; Riley, Brian J.; ...

2016-08-11

Borosilicate glass-ceramics are being developed to immobilize high-level waste generated by aqueous reprocessing into a stable waste form. The corrosion behavior of this multiphase waste form is expected to be complicated by multiple phases and crystal-glass interfaces. A modified single-pass flow-through test was performed on polished monolithic coupons at a neutral pH (25 °C) and 90 °C for 33 d. The measured glass corrosion rates by micro analysis in the samples ranged from 0.019 to 0.29 g m -2 d -1 at a flow rate per surface area = 1.73 × 10 -6 m s -1. The crystal phases (oxyapatitemore » and Ca-rich powellite) corroded below quantifiable rates, by micro analysis. While, Ba-rich powellite corroded considerably in O10 sample. The corrosion rates of C1 and its replicate C20 were elevated an order of magnitude by mechanical stresses at crystal-glass interface caused by thermal expansion mismatch during cooling and unique morphology (oxyapatite clustering).« less

Dilute condition corrosion behavior of glass-ceramic waste form

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crum, Jarrod V.; Neeway, James J.; Riley, Brian J.

Borosilicate glass-ceramics are being developed to immobilize high-level waste generated by aqueous reprocessing into a stable waste form. The corrosion behavior of this multiphase waste form is expected to be complicated by multiple phases and crystal-glass interfaces. A modified single-pass flow-through test was performed on polished monolithic coupons at a neutral pH (25 °C) and 90 °C for 33 d. The measured glass corrosion rates by micro analysis in the samples ranged from 0.019 to 0.29 g m -2 d -1 at a flow rate per surface area = 1.73 × 10 -6 m s -1. The crystal phases (oxyapatitemore » and Ca-rich powellite) corroded below quantifiable rates, by micro analysis. While, Ba-rich powellite corroded considerably in O10 sample. The corrosion rates of C1 and its replicate C20 were elevated an order of magnitude by mechanical stresses at crystal-glass interface caused by thermal expansion mismatch during cooling and unique morphology (oxyapatite clustering).« less

Treatment of radioactive waste salt by using synthetic silica-based phosphate composite for de-chlorination and solidification

NASA Astrophysics Data System (ADS)

Cho, In-Hak; Park, Hwan-Seo; Lee, Ki-Rak; Choi, Jung-Hun; Kim, In-Tae; Hur, Jin Mok; Lee, Young-Seak

2017-09-01

In the radioactive waste management, waste salts as metal chloride generated from a pyrochemical process to recover uranium and transuranic elements are one of problematic wastes due to their intrinsic properties such as high volatility and low compatibility with conventional glasses. This study reports a method to stabilize and solidify LiCl waste via de-chlorination using a synthetic composite, U-SAP (SiO2-Al2O3-B2O3-Fe2O3-P2O5) prepared by a sol-gel process. The composite was reacted with alkali metal elements to produce some metal aluminosilicates, aluminophosphates or orthophosphate as a crystalline or amorphous compound. Different from the original SAP (SiO2-Al2O3-P2O5), the reaction product of U-SAP could be successfully fabricated as a monolithic wasteform without a glassy binder at a proper reaction/consolidation condition. From the results of the FE-SEM, FT-IR and MAS-NMR analysis, it could be inferred that the Si-rich phase and P-rich phase as a glassy grains would be distributed in tens of nm scale, where alkali metal elements would be chemically interacted with Si-rich or P-rich region in the virgin U-SAP composite and its products was vitrified into a silicate or phosphate glass after a heat-treatment at 1150 °C. The PCT-A (Product Consistency Test, ASTM-1208) revealed that the mass loss of Cs and Sr in the U-SAP wasteform had a range of 10-3∼10-1 g/m2 and the leach-resistance of the U-SAP wasteform was comparable to other conventional wasteforms. From the U-SAP method, LiCl waste salt was effectively stabilized and solidified with high waste loading and good leach-resistance.

Vitrified hillforts as anthropogenic analogues for nuclear waste glasses - project planning and initiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sjoblom, Rolf; Weaver, Jamie L.; Peeler, David K.

Nuclear waste must be deposited in such a manner that it does not cause significant impact on the environment or human health. In some cases, the integrity of the repositories will need to sustain for tens to hundreds of thousands of years. In order to ensure such containment, nuclear waste is frequently converted into a very durable glass. It is fundamentally difficult, however, to assure the validity of such containment based on short-term tests alone. To date, some anthropogenic and natural volcanic glasses have been investigated for this purpose. However, glasses produced by ancient cultures for the purpose of joiningmore » rocks in stonewalls have not yet been utilized in spite of the fact that they might offer significant insight into the long-term durability of glasses in natural environments. Therefore, a project is being initiated with the scope of obtaining samples and characterizing their environment, as well as to investigate them using a suite of advanced materials characterization techniques. It will be analysed how the hillfort glasses may have been prepared, and to what extent they have altered under in-situ conditions. The ultimate goals are to obtain a better understanding of the alteration behaviour of nuclear waste glasses and its compositional dependence, and thus to improve and validate models for nuclear waste glass corrosion. The paper deals with project planning and initiation, and also presents some early findings on fusion of amphibolite and on the process for joining the granite stones in the hillfort walls.« less

The effects of crystallization and residual glass on the chemical durability of iron phosphate waste forms containing 40 wt% of a high MoO3 Collins-CLT waste

NASA Astrophysics Data System (ADS)

Hsu, Jen-Hsien; Bai, Jincheng; Kim, Cheol-Woon; Brow, Richard K.; Szabo, Joe; Zervos, Adam

2018-03-01

The effects of cooling rate on the chemical durability of iron phosphate waste forms containing up to 40 wt% of a high MoO3 Collins-CLT waste simulant were determined at 90 °C using the product consistency test (PCT). The waste form, designated 40wt%-5, meets appropriate Department of Energy (DOE) standards when rapidly quenched from the melt (as-cast) and after slow cooling following the CCC (canister centerline cooling)-protocol, although the quenched glass is more durable. The analysis of samples from the vapor hydration test (VHT) and the aqueous corrosion test (differential recession test) reveals that rare earth orthophosphate (monazite) and Zr-pyrophosphate crystals that form on cooling are more durable than the residual glass in the 40wt%-5 waste form. The residual glass in the CCC-treated samples has a greater average phosphate chain length and a lower Fe/P ratio, and those contribute to its faster corrosion kinetics.

Vitrified metal finishing wastes I. Composition, density and chemical durability.

PubMed

Bingham, P A; Hand, R J

2005-03-17

Durable phosphate glasses were formed by vitrifying waste filter cakes from two metal finishing operations. Some melts formed crystalline components during cooling. Compositional analysis of dried, heat treated and vitrified samples was made using energy-dispersive X-ray spectroscopy, X-ray fluorescence spectroscopy, inductively-coupled plasma spectroscopy and Leco induction furnace combustion analysis. Hydrolytic dissolution, measured by an adapted product consistency test, was reduced by up to 3 orders of magnitude upon heat treatment or vitrification, surpassing the performance of borosilicate glass in some cases. This was attributed to the high levels of iron and zinc in the wastes, which greatly improve the durability of phosphate glasses. One of the wastes arose from a metal phosphating process and was particularly suitable for vitrification due to its high P2O5 content and favourable melting behaviour. The other waste, which arose from a number of processes, was less suitable as it had a low P2O5 content and during heating it emitted harmful corrosive gases and underwent violent reactions. Substantial volume reductions were obtained by heat treatment and vitrification of both wastes. Compositions and performances of some vitrified wastes were comparable with those of glasses which are under consideration for the immobilisation of toxic and nuclear wastes.

The development of test methodology for testing glassy materials

NASA Technical Reports Server (NTRS)

Tucker, Dennis S.

1987-01-01

The inherent brittleness of glass invariably leads to a large variability in strength data and a time dependence in strength (i.e., static fatigue). Loading rate plays a large role in strength values. Glass is found to be weaker when supporting loads over long periods as compared to glass which undergoes rapid loading. In this instance the purpose of rapid loading is to fail the glass before any significant crack growth occurs. However, a decrease in strength occurs with a decrease in loading rate, pursuant to substantial crack extension. These properties complicate the structural design allowable for the utilization of glass components in applications such as mirrors for the Space Telescope and AXAF for Spacelab and the space station.

Radiation and Thermal Ageing of Nuclear Waste Glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weber, William J

2014-01-01

The radioactive decay of fission products and actinides incorporated into nuclear waste glass leads to self-heating and self-radiation effects that may affect the stability, structure and performance of the glass in a closed system. Short-lived fission products cause significant self-heating for the first 600 years. Alpha decay of the actinides leads to self-radiation damage that can be significant after a few hundred years, and over the long time periods of geologic disposal, the accumulation of helium and radiation damage from alpha decay may lead to swelling, microstructural evolution and changes in mechanical properties. Four decades of research on the behaviormore » of nuclear waste glass are reviewed.« less

Nano-lead particle synthesis from waste cathode ray-tube funnel glass.

PubMed

Xing, Mingfei; Zhang, Fu-Shen

2011-10-30

Waste cathode ray-tube (CRT) funnel glass is classified as hazardous waste since it contains high amount of lead. In the present study, a novel process for lead nanopowder synthesis from this type of glass was developed by combining vacuum carbon-thermal reduction and inert-gas consolidation procedures. The key trait of the process was to evaporate lead out of the glass to obtain harmless glass powder and synchronously produce lead nanoparticles. In the synthesis process, lead oxide in the funnel glass was firstly reduced to elemental lead, and evaporated rapidly in vacuum circumstance, then quenched and formed nano-size particles on the surface of the cooling device. Experimental results showed that temperature, pressure and argon gas flow rate were the major parameters controlling lead evaporation ratio and the morphology of lead nanoparticles. The maximum lead evaporation ratio was 96.8% and particles of 4-34 nm were successfully obtained by controlling the temperature, holding time, process pressure, argon gas flow rate at 1000°C, 2-4h, 500-2000 Pa, 50-200 ml/min, respectively. Toxicity characteristic leaching procedure (TCLP) results showed that lead leaching from the residue glass met the USEPA threshold. Accordingly, this study developed a practical and environmental-friendly process for detoxification and reclamation of waste lead-containing glass. Copyright © 2011 Elsevier B.V. All rights reserved.

Abrasion Resistance and Mechanical Properties of Waste-Glass-Fiber-Reinforced Roller-compacted Concrete

NASA Astrophysics Data System (ADS)

Yildizel, S. A.; Timur, O.; Ozturk, A. U.

2018-05-01

The potential use of waste glass fibers in roller-compacted concrete (RCC) was investigated with the aim to improve its performance and reduce environmental effects. The research was focused on the abrasion resistance and compressive and flexural strengths of the reinforced concrete relative to those of reference mixes without fibers. The freeze-thaw resistance of RCC mixes was also examined. It was found that the use of waste glass fibers at a rate of 2 % increased the abrasion resistance of the RCC mixes considerably.

Dissimilar behavior of technetium and rhenium in borosilicatewaste glass as determined by X-ray absorption spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lukens, Wayne W.; McKeown, David A.; Buechele, Andrew C.

2006-11-09

Technetium-99 is an abundant, long-lived (t1/2 = 213,000 yr)fission product that creates challenges for the safe, long-term disposalof nuclear waste. While 99Tc receives attention largely due to its highenvironmental mobility, it also causes problems during its incorporationinto nuclear waste glass due to the volatility of Tc(VII) compounds. Thisvolatility decreases the amount of 99Tc stabilized in the waste glass andcauses contamination of the waste glass melter and off-gas system. Theapproach to decrease the volatility of 99Tc that has received the mostattention is reduction of the volatile Tc(VII) species to less volatileTc(IV) species in the glass melt. On engineering scale experiments,rhenium ismore » often used as a non-radioactive surrogate for 99Tc to avoidthe radioactive contamination problems caused by volatile 99Tc compounds.However, Re(VII) is more stable towards reduction than Tc(VII), so morereducing conditions would be required in the glass melt to produceRe(IV). To better understand the redox behavior of Tc and Re in nuclearwaste glass, a series of glasses were prepared under different redoxconditions. The speciation of Tc and Re in the resulting glasses wasdetermined by X-ray absorption fine structure spectroscopy. Surprisingly,Re and Tc do not behave similarly in the glass melt. Although Tc(0),Tc(IV), and Tc(VII) were observed in these samples, only Re(0) andRe(VII) were found. In no case was Re(IV) (or Re(VI))observed.« less

Assessment of lead tellurite glass for immobilizing electrochemical salt wastes from used nuclear fuel reprocessing

NASA Astrophysics Data System (ADS)

Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.; Pierce, David A.; Ebert, William L.; Williams, Benjamin D.; Snyder, Michelle M. V.; Frank, Steven M.; George, Jaime L.; Kruska, Karen

2017-11-01

This paper provides an overview of research evaluating the use of lead tellurite glass as a waste form for salt wastes from electrochemical reprocessing of used nuclear fuel. The efficacy of using lead tellurite glass to immobilize three different salt compositions was evaluated: a LiCl-Li2O oxide reduction salt containing fission products from oxide fuel, a LiCl-KCl eutectic salt containing fission products from metallic fuel, and SrCl2. Physical and chemical properties of glasses made with these salts were characterized with X-ray diffraction, bulk density measurements, differential thermal analysis, chemical durability tests, scanning and transmission electron microscopies, and energy-dispersive X-ray spectroscopy. These glasses were found to accommodate high salt concentrations and have high densities, but further development is needed to improve chemical durability.

Conversion of Nuclear Waste to Molten Glass: Cold-Cap Reactions in Crucible Tests

DOE PAGES

Xu, Kai; Hrma, Pavel; Rice, Jarrett A.; ...

2016-05-23

The feed-to-glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold cap during nuclear waste vitrification. Here, to investigate the conversion process, we analyzed heat-treated samples of a simulated high-level waste feed using X-ray diffraction, electron probe microanalysis, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700°C before the emerging glass-forming melt was completely connected. Above 700°C, intermediate aluminosilicate phases and quartz particles gradually dissolved in the continuous borosilicate melt, which expanded with transient foam. Finally, knowledge of the chemistry and physics of feed-to-glass conversion willmore » help us control the conversion path by changing the melter feed makeup to maximize the glass production rate.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

NASA Astrophysics Data System (ADS)

Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong; Wang, Guohui; Schweiger, Michael J.; Soderquist, Chuck Z.; Lukens, Wayne; Kruger, Albert A.

2018-05-01

Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO2•2H2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.

Feasibility study on cross-linked biopolymeric concrete encapsulating selenium glass wastes.

PubMed

Kim, Daeik; Park, Joon-Seok; Yen, Teh Fu

2012-08-01

Feasibility study was conducted to encapsulate the selenium (Se) contained in glass waste, using the biopolymer-modified concrete. Biopolymer has unique characteristics to provide the chemical sites to metals or toxic compounds through the three-dimensional cross-linked structure. Very minute amount of biopolymer enhanced the characteristics of cementitious material. The resulting biopolymeric composite with selenium glass waste showed 20% higher compressive strength than ordinary concrete and the lower leaching concentration than the equipment detection limit. For a qualitative measurement, X-ray diffraction (XRD; X-ray powder diffractogram) was used to characterize the biopolymeric concrete. The optimum waste content percentage with appropriate biopolymer concrete mixture ratio was identified for its possible commercial use.

Lead recovery and glass microspheres synthesis from waste CRT funnel glasses through carbon thermal reduction enhanced acid leaching process.

PubMed

Mingfei, Xing; Yaping, Wang; Jun, Li; Hua, Xu

2016-03-15

In this study, a novel process for detoxification and reutilization of waste cathode ray tube (CRT) funnel glass was developed by carbon thermal reduction enhanced acid leaching process. The key to this process is removal of lead from the CRT funnel glass and synchronous preparation of glass microspheres. Carbon powder was used as an isolation agent and a reducing agent. Under the isolation of the carbon powder, the funnel glass powder was sintered into glass microspheres. In thermal reduction, PbO in the funnel glass was first reduced to elemental Pb by carbon monoxide and then located on the surface of glass microspheres which can be removed easily by acid leaching. Experimental results showed that temperature, carbon adding amount and holding time were the major parameters that controlled lead removal rate. The maximum lead removal rate was 94.80% and glass microspheres that measured 0.73-14.74μm were obtained successfully by setting the temperature, carbon adding amount and holding time at 1200°C, 10% and 30min, respectively. The prepared glass microspheres may be used as fillers in polymer materials and abrasive materials, among others. Accordingly, this study proposed a practical and economical process for detoxification and recycling of waste lead-containing glass. Copyright © 2015 Elsevier B.V. All rights reserved.

Using Natural Cementation Systems to Control Corrosion Dust on Un-surfaced Roads

DTIC Science & Technology

2010-02-01

metallurgical slags ), volcanic glass , fly ash and low-fired clays • Can use waste alkali from manufacturing operations • No Portland cement is involved Soil...solidified with alkali- activated glass slag US Army Corps of Engineers 4 Pohakuloa Training Area (PTA) as a Test Site • Serious dust problem at site...Conventional Cement? • Glass can be both the aggregate and form the cementing phase • Waste glass ( slag , fly ash) can be used • More alkaline solution is

Ion-Exchange Interdiffusion Model with Potential Application to Long-Term Nuclear Waste Glass Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neeway, James Joseph; Kerisit, Sebastien N.; Liu, Jia

2016-05-05

Abstract: Ion exchange is an integral mechanism influencing the corrosion of glasses. Due to the formation of alteration layers in aqueous conditions, it is difficult to conclusively deconvolute the process of ion exchange from other processes, principally dissolution of the glass matrix. Therefore, we have developed a method to isolate alkali diffusion that involves contacting glass coupons with a solution of 6LiCl dissolved in functionally inert dimethyl sulfoxide. We employ the method at temperatures ranging from 25 to 150 °C with various glass formulations. Glass compositions include simulant nuclear waste glasses, such as SON68 and the international simple glass (ISG),more » glasses in which the nature of the alkali element was varied, and glasses that contained more than one alkali element. An interdiffusion model based on Fick’s second law was developed and applied to all experiments to extract diffusion coefficients. The model expands established models of interdiffusion to the case where multiple types of alkali sites are present in the glass. Activation energies for alkali ion exchange were calculated and the results are in agreement with those obtained in glass strengthening experiments but are nearly five times higher than values reported for diffusion-controlled processes in nuclear waste glass corrosion experiments. A discussion of the root causes for this apparent discrepancy is provided. The interdiffusion model derived from laboratory experiments is expected to be useful for modeling glass corrosion in a geological repository when the silicon concentration is high.« less

Gamma radiation induced changes in nuclear waste glass containing Eu

NASA Astrophysics Data System (ADS)

Mohapatra, M.; Kadam, R. M.; Mishra, R. K.; Kaushik, C. P.; Tomar, B. S.; Godbole, S. V.

2011-10-01

Gamma radiation induced changes were investigated in sodium-barium borosilicate glasses containing Eu. The glass composition was similar to that of nuclear waste glasses used for vitrifying Trombay research reactor nuclear waste at Bhabha Atomic Research Centre, India. Photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques were used to study the speciation of the rare earth (RE) ion in the matrix before and after gamma irradiation. Judd-Ofelt ( J- O) analyses of the emission spectra were done before and after irradiation. The spin counting technique was employed to quantify the number of defect centres formed in the glass at the highest gamma dose studied. PL data suggested the stabilisation of the trivalent RE ion in the borosilicate glass matrix both before and after irradiation. It was also observed that, the RE ion distributes itself in two different environments in the irradiated glass. From the EPR data it was observed that, boron oxygen hole centre based radicals are the predominant defect centres produced in the glass after irradiation along with small amount of E’ centres. From the spin counting studies the concentration of defect centres in the glass was calculated to be 350 ppm at 900 kGy. This indicated the fact that bulk of the glass remained unaffected after gamma irradiation up to 900 kGy.

Glass-bonded iodosodalite waste form for immobilization of 129 I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chong, Saehwa; Peterson, Jacob A.; Riley, Brian J.

Immobilization of radioiodine (e.g., 129I, 131I) is an important need for current and future nuclear fuel cycles. For the current work, iodosodalite [Na8(AlSiO4)6I2] was synthesized hydrothermally from metakaolin, NaI, and NaOH. Following hydrothermal treatment, dried unwashed powders were used to make glass-bonded iodosodalite waste forms by heating pressed pellets at 650, 750, or 850 °C with two different types of sodium borosilicate glass binders, i.e., NBS-4 and SA-800. These heat-treated specimens were characterized with X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, thermal analysis, porosity and density measurements, neutron activation analysis, and inductively-coupled plasma mass spectrometry. Themore » pellets mixed with 10 mass% of NBS-4 or SA-800 and heat-treated at 750 °C contained relatively high percentage iodine retention (~44-47 % of the maximum iodine loading) with relatively low porosities, while other pellets with higher percentages iodine retention either contained higher porosity or were not completely sintered. ASTM C1308 chemical durability tests of monolithic specimens showed a large initial release of Na, Al, Si, and I on the first day, possibly from water-soluble salt crystals or non-durable amorphous phases. Release rates of Na and Si were higher than for Al and I, probably due to a poorly durable Na-Si-O phase from the glass bonding matrix. The cumulative normalized release of iodine was 12.5 g m-2 for the first 10 1-d exchanges, suggestive of coherent dissolution. The average release rate from 10-24 days during the 7-d exchange intervals was 0.2336 g m-2 d-1.« less

Melter feed viscosity during conversion to glass: Comparison between low-activity waste and high-level waste feeds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Tongan; Chun, Jaehun; Dixon, Derek R.

During nuclear waste vitrification, a melter feed (generally a slurry-like mixture of a nuclear waste and various glass forming and modifying additives) is charged into the melter where undissolved refractory constituents are suspended together with evolved gas bubbles from complex reactions. Knowledge of flow properties of various reacting melter feeds is necessary to understand their unique feed-to-glass conversion processes occurring within a floating layer of melter feed called a cold cap. The viscosity of two low-activity waste (LAW) melter feeds were studied during heating and correlated with volume fractions of undissolved solid phase and gas phase. In contrast to themore » high-level waste (HLW) melter feed, the effects of undissolved solid and gas phases play comparable roles and are required to represent the viscosity of LAW melter feeds. This study can help bring physical insights to feed viscosity of reacting melter feeds with different compositions and foaming behavior in nuclear waste vitrification.« less

Product/Process (P/P) Models For The Defense Waste Processing Facility (DWPF): Model Ranges And Validation Ranges For Future Processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C.; Edwards, T.

Radioactive high level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-compositionmore » models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository.« less

Evaluation of lead recovery efficiency from waste CRT funnel glass by chlorinating volatilization process.

PubMed

Erzat, Aris; Zhang, Fu-Shen

2014-01-01

The current study was carried out to develop a novel process, namely chloride volatilization procedure for lead recovery from waste cathode ray tube (CRT) funnel glass. In the recovery system, the glass powder was first compressed into cylindrical pellet homogeneously with chlorinating agents, and then subjected to thermal treatment for solid-phase reaction. In this case, lead could be easily released from the silicon oxide network of the glass and it was recovered in the form of PbCl₂. It was found that CaCl2 was the most effective chlorinating agent, and the optimum operation temperature, holding time and system pressure were 1000 °C, 2 h, 600 ± 50 Pa, respectively. The evaporated PbCl₂could be easily recovered by a cooling device. The evaporation ratio of lead from waste CRT was 99.1% and the purity of the recovered PbCl₂product was 97.0%. The reaction routes and lead recovery mechanisms of the process were identified. This study provides an efficient and practical process for waste CRT funnel glass detoxification and recycling.

Environmental Assessment: Construction and Operation of Headquarters Air Force Reserve Command Campus

DTIC Science & Technology

2010-01-21

Headquarters AFRC Campus 2 January 21, 2010 ( pest /vegetation control and oil spill dispersal) using...activities is generated at the Proposed Action Site. This solid waste includes kitchen waste, paper, plastics, metal and glass containers, and standard...includes kitchen waste, paper, plastics, metal and glass containers, and standard housekeeping materials, and is handled in accordance with Robins

Long-term modeling of glass waste in portland cement- and clay-based matrices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stockman, H.W.; Nagy, K.L.; Morris, C.E.

A set of ``templates`` was developed for modeling waste glass interactions with cement-based and clay-based matrices. The templates consist of a modified thermodynamic database, and input files for the EQ3/6 reaction path code, containing embedded rate models and compositions for waste glass, cement, and several pozzolanic materials. Significant modifications were made in the thermodynamic data for Th, Pb, Ra, Ba, cement phases, and aqueous silica species. It was found that the cement-containing matrices could increase glass corrosion rates by several orders of magnitude (over matrixless or clay matrix systems), but they also offered the lowest overall solubility for Pb, Ra,more » Th and U. Addition of pozzolans to cement decreased calculated glass corrosion rates by up to a factor of 30. It is shown that with current modeling capabilities, the ``affinity effect`` cannot be trusted to passivate glass if nuclei are available for precipitation of secondary phases that reduce silica activity.« less

Using of borosilicate glass waste as a cement additive

NASA Astrophysics Data System (ADS)

Han, Weiwei; Sun, Tao; Li, Xinping; Sun, Mian; Lu, Yani

2016-08-01

Borosilicate glass waste is investigated as a cement additive in this paper to improve the properties of cement and concrete, such as setting time, compressive strength and radiation shielding. The results demonstrate that borosilicate glass is an effective additive, which not only improves the radiation shielding properties of cement paste, but also shows the irradiation effect on the mechanical and optical properties: borosilicate glass can increase the compressive strength and at the same time it makes a minor impact on the setting time and main mineralogical compositions of hydrated cement mixtures; and when the natural river sand in the mortar is replaced by borosilicate glass sand (in amounts from 0% to 22.2%), the compressive strength and the linear attenuation coefficient firstly increase and then decrease. When the glass waste content is 14.8%, the compressive strength is 43.2 MPa after 28 d and the linear attenuation coefficient is 0.2457 cm-1 after 28 d, which is beneficial for the preparation of radiation shielding concrete with high performances.

Conversion of Nuclear Waste to Molten Glass: Cold-Cap Reactions in Crucible Tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Kai; Hrma, Pavel; Rice, Jarrett A.

2016-05-23

The feed-to-glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold-cap zone during nuclear waste vitrification. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate. To investigate the conversion process, we analyzed heat-treated samples of a simulated high-level waste feed using X-ray diffraction, electron probe microanalysis – wavelength dispersive X-ray spectroscopy, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700 °C before the emerging glass-forming melt wasmore » completely connected. Above 800 °C, intermediate aluminosilicate phases and quartz particles were gradually dissolving in the continuous borosilicate melt, which expanded into transient foam. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raszewski, F; Tommy Edwards, T; David Peeler, D

Sludge Batch 4 (SB4) is currently being processed in the Defense Waste Processing Facility (DWPF) using Frit 510. The slurry pumps in Tank 40 are experiencing in-leakage of bearing water, which is causing the sludge slurry in Tank 40 to become dilute at a rapid rate. Currently, the DWPF is removing this dilution water by performing caustic boiling during the Sludge Receipt and Adjustment Tank (SRAT) cycle. In order to alleviate prolonged SRAT cycle times, which may eventually impact canister production rates, the Liquid Waste Organization (LWO) performed a 100K gallon supernate decant of Tank 40 in April 2008. SRNLmore » performed a supplemental glass variability study to support the April 2008 100K gallon decant incorporating the impact of coupled operations (addition of the Actinide Removal Process (ARP) stream). Recently LWO requested that SRNL assess the impact of a second decant (up to 100K gallon) to the Frit 510-SB4 system. This second decant occurred in June 2008. LWO provided nominal compositions on May 6, 2008 representing Tank 40 prior to the second decant, following the second decant, and the SB4 Heel prior to blending with Tank 51 to constitute SB5. Paper study assessments were performed for these options based on sludge-only and coupled operations processing (ARP addition), as well as possible Na{sub 2}O additions (via NaOH additions) to both flowsheets. A review of the ComProTM database relative to the compositional region defined by the projections after the second decant coupled with Frit 510 identified only a few glasses with similar glass compositions. These glasses were acceptable from a durability perspective, but did not sufficiently cover the new glass compositional region. Therefore, SRNL recommended that a supplemental variability study be performed to support the June 2008 Tank 40 decant. Glasses were selected for the variability study based on three sludge compositional projections (sludge-only, coupled and coupled + 2 wt% Na{sub 2}O) at waste loadings (WLs) of interest to DWPF (32%, 35% and 38%). These nine glasses were fabricated and characterized using chemical composition analysis, X-ray Diffraction (XRD) and the Product Consistency Test (PCT). All of the glasses that were selected for this study satisfy the Product Composition Control System (PCCS) criteria and are deemed processable and acceptable for the DWPF, except for the SB4VS2-03 (sludge-only at 38% WL) target composition. This glass fails the T{sub L} criterion and would not be considered processable based on Slurry Mix Evaporator (SME) acceptability decisions. The durabilities of all of the study glasses (both quenched and ccc) are well below that of the normalized leachate for boron (NL [B]) of the reference EA glass (16.695 g/L) and are predictable using the current PCCS models. Very little variation exists between the NL [B] of the quenched and ccc versions of the glasses. There is some evidence of a trend toward a less durable glass as WL increases for some of the sludge projections. Frit 510 is a viable option for the processing of SB4 after a second Tank 40 decant with or without the addition of products from the ARP stream as well as the 2 wt% Na{sub 2}O addition. The addition of ARP had no negative impacts on the acceptability and predictability of the variability study glasses.« less

Accelerated Leach Testing of Glass (ALTGLASS): II. Mineralization of hydrogels by leachate strong bases

DOE PAGES

Jantzen, Carol M.; Trivelpiece, Cory L.; Crawford, Charles L.; ...

2017-02-18

The durability of high level nuclear waste glasses must be predicted on geological time scales. Waste glass surfaces form hydrogels when in contact with water for varying test durations. As the glass hydrogels age, some exhibit an undesirable resumption of dissolution at long times while others exhibit near steady-state dissolution, that is, nonresumption of dissolution. Resumption of dissolution is associated with the formation of zeolitic phases while nonresumption of dissolution is associated with the formation of clay minerals. Hydrogels with a stoichiometry close to that of imogolite, (Al 2O 3·Si(OH) 4), with ferrihydrite (Fe 2O 3·0.5H 2O), have been shownmore » to be associated with waste glasses that resume dissolution. Aluminosilicate hydrogels with a stoichiometry of allophane-hisingerite ((Al,Fe) 2O 3·1.3-2Si(OH) 4) have been shown to be associated with waste glasses that exhibit near steady-state dissolution at long times. These phases are all amorphous and poorly crystalline and are also found on natural weathered basalt glasses. Interaction of these hydrogels with excess alkali and OH – (strong base) in the leachates, causes the Al 2O 3· nSiO 2 (where n=1-2) hydrogels to mineralize to zeolites. Excess alkali in the leachate is generated by alkali in the glass. As a result, preliminary rate-determining leach layer forming exchange reactions are hypothesized based on these findings.« less

Accelerated Leach Testing of Glass (ALTGLASS): II. Mineralization of hydrogels by leachate strong bases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol M.; Trivelpiece, Cory L.; Crawford, Charles L.

The durability of high level nuclear waste glasses must be predicted on geological time scales. Waste glass surfaces form hydrogels when in contact with water for varying test durations. As the glass hydrogels age, some exhibit an undesirable resumption of dissolution at long times while others exhibit near steady-state dissolution, that is, nonresumption of dissolution. Resumption of dissolution is associated with the formation of zeolitic phases while nonresumption of dissolution is associated with the formation of clay minerals. Hydrogels with a stoichiometry close to that of imogolite, (Al 2O 3·Si(OH) 4), with ferrihydrite (Fe 2O 3·0.5H 2O), have been shownmore » to be associated with waste glasses that resume dissolution. Aluminosilicate hydrogels with a stoichiometry of allophane-hisingerite ((Al,Fe) 2O 3·1.3-2Si(OH) 4) have been shown to be associated with waste glasses that exhibit near steady-state dissolution at long times. These phases are all amorphous and poorly crystalline and are also found on natural weathered basalt glasses. Interaction of these hydrogels with excess alkali and OH – (strong base) in the leachates, causes the Al 2O 3· nSiO 2 (where n=1-2) hydrogels to mineralize to zeolites. Excess alkali in the leachate is generated by alkali in the glass. As a result, preliminary rate-determining leach layer forming exchange reactions are hypothesized based on these findings.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

DOE PAGES

Luksic, Steven A.; Kim, Dong Sang; Um, Wooyong; ...

2018-03-02

Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO 2∙2H 2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. Here, we postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Finally,more » additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.« less

Assessment of lead tellurite glass for immobilizing electrochemical salt wastes from used nuclear fuel reprocessing

DOE PAGES

Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.; ...

2017-08-30

Here, this paper provides an overview of research evaluating the use of lead tellurite glass as a waste form for salt wastes from electrochemical reprocessing of used nuclear fuel. The efficacy of using lead tellurite glass to immobilize three different salt compositions was evaluated: a LiCl-Li 2O oxide reduction salt containing fission products from oxide fuel, a LiCl-KCl eutectic salt containing fission products from metallic fuel, and SrCl 2. Physical and chemical properties of glasses made with these salts were characterized with X-ray diffraction, bulk density measurements, differential thermal analysis, chemical durability tests, scanning and transmission electron microscopies, and energy-dispersivemore » X-ray spectroscopy. These glasses were found to accommodate high salt concentrations and have high densities, but further development is needed to improve chemical durability.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong

Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO2∙2H2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with hexavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Additional studies are neededmore » to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from glass melt.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luksic, Steven A.; Kim, Dong Sang; Um, Wooyong

Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO 2∙2H 2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. Here, we postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Finally,more » additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong

© 2018 Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO 2 ∙2H 2 O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generallymore » accepted idea. Additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.« less

Effect of Technetium-99 sources on its retention in low activity waste glass

DOE PAGES

Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong; ...

2018-05-01

© 2018 Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO 2 ∙2H 2 O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generallymore » accepted idea. Additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.« less

Elaboration And Characterization Of Foam Glass Based On Cullet With Addition Of Soluble Silicates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ayadi, A.; Stiti, N.; Benhaoua, F.

2011-01-17

The politics of the energy saving and of the acoustic comfort buildings is at the heart of the research of new compounds permitting to improve the materials performance actually commercialised. With this aim in view, we'll purpose to elaborate a porous material (foam glass) with addition of soluble silicates (up to 40%) of which the principal material is the waste glass in order to recycle it and improving the present laws about the waste products in closed circuit: (Finished products (leftarrow) waste products (leftarrow) finished products). The investigations have shown that grinding waste glass to particle size less than 0.1more » mm and adding 1% of Ca CO{sub 3} content provide production of material with the following properties: particle density 0,5 g/cm{sup 3}, strength 17,50 MPa and water adsorption 95%, the temperature for foaming ranges were determined at 850 deg. C. The microstructures are homogenous, with pore sizes up to 2 mm. The addition of soluble silicates (up to 40%) has resulted in the foam glass of very high porosity. The foam glass is counted among the new glass products meeting certain requirements sought comfort in the building industry in particular (thermal and acoustic insulation). The product obtained present of excellent properties thermal ({lambda} = 0,031 W/m deg. C) and acoustic (R = 15 dB).« less

Elaboration And Characterization Of Foam Glass Based On Cullet With Addition Of Soluble Silicates

NASA Astrophysics Data System (ADS)

Ayadi, A.; Stiti, N.; Benhaoua, F.; Boumchedda, K.; Lerari, Y.

2011-01-01

The politics of the energy saving and of the acoustic comfort buildings is at the heart of the research of new compounds permitting to improve the materials performance actually commercialised. With this aim in view, we'll purpose to elaborate a porous material (foam glass) with addition of soluble silicates (up to 40%) of which the principal material is the waste glass in order to recycle it and improving the present laws about the waste products in closed circuit: (Finished products ← waste products← finished products). The investigations have shown that grinding waste glass to particle size less than 0.1 mm and adding 1% of Ca CO3 content provide production of material with the following properties: particle density 0,5 g/cm3, strength 17,50 MPa and water adsorption 95%, the temperature for foaming ranges were determined at 850° C. The microstructures are homogenous, with pore sizes up to 2 mm. The addition of soluble silicates (up to 40%) has resulted in the foam glass of very high porosity. The foam glass is counted among the new glass products meeting certain requirements sought comfort in the building industry in particular (thermal and acoustic insulation). The product obtained present of excellent properties thermal (λ = 0,031 W/m° C) and acoustic (R = 15 dB).

Anaerobic digestion of pressed off leachate from the organic fraction of municipal solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nayono, Satoto E.; Institute of Biology for Engineers and Biotechnology of Wastewater, University of Karlsruhe, Am Fasanengarten, 76131 Karlsruhe; Winter, Josef, E-mail: josef.winter@iba.uka.d

2010-10-15

A highly polluted liquid ('press water') was obtained from the pressing facility for the organic fraction of municipal solid waste in a composting plant. Methane productivity of the squeezed-off leachate was investigated in batch assays. To assess the technical feasibility of 'press water' as a substrate for anaerobic digestion, a laboratory-scale glass column reactor was operated semi-continuously at 37 {sup o}C. A high methane productivity of 270 m{sup -3} CH{sub 4} ton{sup -1} COD{sub added} or 490 m{sup -3} CH{sub 4} ton{sup -1} VS{sub added} was achieved in the batch experiment. The semi-continuously run laboratory-scale reactor was initially operated atmore » an organic loading rate of 10.7 kg COD m{sup -3} d{sup -1}. The loading was increased to finally 27.7 kg COD m{sup -3} d{sup -1}, corresponding to a reduction of the hydraulic retention time from initially 20 to finally 7.7 days. During the digestion, a stable elimination of organic material (measured as COD elimination) of approximately 60% was achieved. Linearly with the increment of the OLR, the volumetric methane production of the reactor increased from 2.6 m{sup 3} m{sub reactor}{sup -3} d{sup -1} to 7.1 m{sup 3} m{sub reactor}{sup -3} d{sup -1}. The results indicated that 'press water' from the organic fraction of municipal solid waste was a suitable substrate for anaerobic digestion which gave a high biogas yield even at very high loading rates.« less

ARRHENIUS MODEL FOR HIGH-TEMPERATURE GLASS VISCOSITY WITH A CONSTANT PRE-EXPONENTIAL FACTOR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrma, Pavel R.

2008-04-15

A simplified form of the Arrhenius equation, ln η = A + B(x)/T, where η is the viscosity, T the temperature, x the composition vector, and A and B the Arrhenius coefficients, was fitted to glass-viscosity data for the processing temperature range (the range at which the viscosity is within 1 to 103 Pa.s) while setting A = constant and treating B(x) as a linear function of mass fractions of major components. Fitting the Arrhenius equation to over 550 viscosity data of commercial glasses and approximately 1000 viscosity data of glasses for nuclear-waste glasses resulted in the A values ofmore » -11.35 and -11.48, respectively. The R2 value ranged from 0.92 to 0.99 for commercial glasses and was 0.98 for waste glasses. The Arrhenius models estimate viscosities for melts of commercial glasses containing 42 to 84 mass% SiO2 within the temperature range of 1100 to 1550°C and viscosity range of 5 to 400 Pa.s and for waste glasses containing 32 to 60 mass% SiO2 within the temperature range of 850 to 1450°C and viscosity range of 0.4 to 250 Pa.s.« less

The use of positrons to survey alteration layers on synthetic nuclear waste glasses

NASA Astrophysics Data System (ADS)

Reiser, Joelle T.; Parruzot, Benjamin; Weber, Marc H.; Ryan, Joseph V.; McCloy, John S.; Wall, Nathalie A.

2017-07-01

In order to safeguard society and the environment, understanding radioactive waste glass alteration mechanisms in interactions with solutions and near-field materials, such as Fe, is essential to nuclear waste repository performance assessments. Alteration products are formed at the surface of glasses after reaction with solution. In this study, glass altered in the presence of Fe0 in aqueous solution formed two alteration layers: one embedded with Fe closer to the surface and one without Fe found deeper in the sample. Both layers were found to be thinner than the alteration layer found in glass altered in aqueous solution only. For the first time, Doppler Broadening Positron Annihilation Spectroscopy (DB-PAS) is used to non-destructively characterize the pore structures of glass altered in the presence of Fe0. Advantages and disadvantages of DB-PAS compared to other techniques used to analyze pore structures for altered glass samples are discussed. Ultimately, DB-PAS has shown to be an excellent choice for pore structure characterization for glasses with multiple alteration layers. Monte Carlo modeling predicted positron trajectories through the layers, and helped explain DB-PAS data, which showed that the deeper alteration layer without Fe had a similar composition and pore structure to layers on glass altered in water only.

The use of positrons to survey alteration layers on synthetic nuclear waste glasses

DOE PAGES

Reiser, Joelle T.; Parruzot, Benjamin; Weber, Marc H.; ...

2017-07-01

Here, in order to safeguard society and the environment, understanding radioactive waste glass alteration mechanisms in interactions with solutions and near-field materials, such as Fe, is essential to nuclear waste repository performance assessments. Alteration products are formed at the surface of glasses after reaction with solution. In this study, glass altered in the presence of Fe 0 in aqueous solution formed two alteration layers: one embedded with Fe closer to the surface and one without Fe found deeper in the sample. Both layers were found to be thinner than the alteration layer found in glass altered in aqueous solution only.more » For the first time, Doppler Broadening Positron Annihilation Spectroscopy (DB-PAS) is used to non-destructively characterize the pore structures of glass altered in the presence of Fe 0. Advantages and disadvantages of DB-PAS compared to other techniques used to analyze pore structures for altered glass samples are discussed. Ultimately, DB-PAS has shown to be an excellent choice for pore structure characterization for glasses with multiple alteration layers. Monte Carlo modeling predicted positron trajectories through the layers, and helped explain DB-PAS data, which showed that the deeper alteration layer without Fe had a similar composition and pore structure to layers on glass altered in water only.« less

The use of positrons to survey alteration layers on synthetic nuclear waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reiser, Joelle T.; Parruzot, Benjamin; Weber, Marc H.

Here, in order to safeguard society and the environment, understanding radioactive waste glass alteration mechanisms in interactions with solutions and near-field materials, such as Fe, is essential to nuclear waste repository performance assessments. Alteration products are formed at the surface of glasses after reaction with solution. In this study, glass altered in the presence of Fe 0 in aqueous solution formed two alteration layers: one embedded with Fe closer to the surface and one without Fe found deeper in the sample. Both layers were found to be thinner than the alteration layer found in glass altered in aqueous solution only.more » For the first time, Doppler Broadening Positron Annihilation Spectroscopy (DB-PAS) is used to non-destructively characterize the pore structures of glass altered in the presence of Fe 0. Advantages and disadvantages of DB-PAS compared to other techniques used to analyze pore structures for altered glass samples are discussed. Ultimately, DB-PAS has shown to be an excellent choice for pore structure characterization for glasses with multiple alteration layers. Monte Carlo modeling predicted positron trajectories through the layers, and helped explain DB-PAS data, which showed that the deeper alteration layer without Fe had a similar composition and pore structure to layers on glass altered in water only.« less

Experimental Verification of the Structural Glass Beam-Columns Strength

NASA Astrophysics Data System (ADS)

Pešek, Ondřej; Melcher, Jindřich; Balázs, Ivan

2017-10-01

This paper deals with experimental research of axially and laterally loaded members made of structural (laminated) glass. The purpose of the research is the evaluation of buckling strength and actual behaviour of the beam-columns due to absence of standards for design of glass load-bearing structures. The experimental research follows the previous one focusing on measuring of initial geometrical imperfections of glass members, testing of glass beams and columns. Within the frame of the research 9 specimens were tested. All of them were of the same geometry (length 2000 mm, width 200 mm and thickness 16 mm) but different composition - laminated double glass made of annealed glass or fully tempered glass panes bonded together by PVB or EVASAFE foil. Specimens were at first loaded by axial force and then by constantly increasing bending moment up to failure. During testing lateral deflections, vertical deflection and normal stresses at mid-span were measured. A maximum load achieved during testing has been adopted as flexural-lateral-torsional buckling strength. The results of experiments were statistically evaluated according to the European standard for design of structures EN 1990, appendix D. There are significant differences between specimens made of annealed glass or fully tempered glass. Differences between specimens loaded by axial forces 1 kN and 2 kN are negligible. The next step was to determine the design strength by calculation procedure based on buckling curves approach intended for design of steel columns and develop interaction criterion for glass beams-columns.

Magnetic Glass Ceramics by Sintering of Borosilicate Glass and Inorganic Waste.

PubMed

Ponsot, Inès M M M; Pontikes, Yiannis; Baldi, Giovanni; Chinnam, Rama K; Detsch, Rainer; Boccaccini, Aldo R; Bernardo, Enrico

2014-07-31

Ceramics and glass ceramics based on industrial waste have been widely recognized as competitive products for building applications; however, there is a great potential for such materials with novel functionalities. In this paper, we discuss the development of magnetic sintered glass ceramics based on two iron-rich slags, coming from non-ferrous metallurgy and recycled borosilicate glass. The substantial viscous flow of the glass led to dense products for rapid treatments at relatively low temperatures (900-1000 °C), whereas glass/slag interactions resulted in the formation of magnetite crystals, providing ferrimagnetism. Such behavior could be exploited for applying the obtained glass ceramics as induction heating plates, according to preliminary tests (showing the rapid heating of selected samples, even above 200 °C). The chemical durability and safety of the obtained glass ceramics were assessed by both leaching tests and cytotoxicity tests.

Magnetic Glass Ceramics by Sintering of Borosilicate Glass and Inorganic Waste

PubMed Central

Ponsot, Inès M. M. M.; Pontikes, Yiannis; Baldi, Giovanni; Chinnam, Rama K.; Detsch, Rainer; Boccaccini, Aldo R.; Bernardo, Enrico

2014-01-01

Ceramics and glass ceramics based on industrial waste have been widely recognized as competitive products for building applications; however, there is a great potential for such materials with novel functionalities. In this paper, we discuss the development of magnetic sintered glass ceramics based on two iron-rich slags, coming from non-ferrous metallurgy and recycled borosilicate glass. The substantial viscous flow of the glass led to dense products for rapid treatments at relatively low temperatures (900–1000 °C), whereas glass/slag interactions resulted in the formation of magnetite crystals, providing ferrimagnetism. Such behavior could be exploited for applying the obtained glass ceramics as induction heating plates, according to preliminary tests (showing the rapid heating of selected samples, even above 200 °C). The chemical durability and safety of the obtained glass ceramics were assessed by both leaching tests and cytotoxicity tests. PMID:28788146

Tin Valence and Local Environments in Silicate Glasses as Determined From X-ray Absorption Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKeown,D.; Buechele, A.; Gan, H.

2008-01-01

X-ray absorption spectroscopy (XAS) was used to characterize the tin (Sn) environments in four borosilicate glass nuclear waste formulations, two silicate float glasses, and three potassium aluminosilicate glasses. Sn K-edge XAS data of most glasses investigated indicate Sn4+O6 units with average Sn-O distances near 2.03 Angstroms. XAS data for a float glass fabricated under reducing conditions show a mixture of Sn4+O6 and Sn2+O4 sites. XAS data for three glasses indicate Sn-Sn distances ranging from 3.43 to 3.53 Angstroms, that suggest Sn4+O6 units linking with each other, while the 4.96 Angstroms Sn-Sn distance for one waste glass suggests clustering of unlinkedmore » Sn4+O6 units.« less

Defense waste processing facility (DWPF) liquids model: revisions for processing higher TIO 2 containing glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C. M.; Edwards, T. B.; Trivelpiece, C. L.

Radioactive high level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-compositionmore » models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository. This report documents the development of revised TiO 2, Na 2O, Li 2O and Fe 2O 3 coefficients in the SWPF liquidus model and revised coefficients (a, b, c, and d).« less

X-ray absorption studies of chlorine valence and local environments in borosilicate waste glasses

NASA Astrophysics Data System (ADS)

McKeown, David A.; Gan, Hao; Pegg, Ian L.; Stolte, W. C.; Demchenko, I. N.

2011-01-01

Chlorine (Cl) is a constituent of certain types of nuclear wastes and its presence can affect the physical and chemical properties of silicate melts and glasses developed for the immobilization of such wastes. Cl K-edge X-ray absorption spectra (XAS) were collected and analyzed to characterize the unknown Cl environments in borosilicate waste glass formulations, ranging in Cl-content from 0.23 to 0.94 wt.%. Both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data for the glasses show trends dependent on calcium (Ca) content. Near-edge data for the Ca-rich glasses are most similar to the Cl XANES of CaCl 2, where Cl - is coordinated to three Ca atoms, while the XANES for the Ca-poor glasses are more similar to the mineral davyne, where Cl is most commonly coordinated to two Ca in one site, as well as Cl and oxygen nearest-neighbors in other sites. With increasing Ca content in the glass, Cl XANES for the glasses approach that for CaCl 2, indicating more Ca nearest-neighbors around Cl. Reliable structural information obtained from the EXAFS data for the glasses is limited, however, to Cl sbnd Cl, Cl sbnd O, and Cl sbnd Na distances; Cl sbnd Ca contributions could not be fit to the glass data, due to the narrow k-space range available for analysis. Structural models that best fit the glass EXAFS data include Cl sbnd Cl, Cl sbnd O, and Cl sbnd Na correlations, where Cl sbnd O and Cl sbnd Na distances decrease by approximately 0.16 Å as glass Ca content increases. XAS for the glasses indicates Cl - is found in multiple sites where most Cl-sites have Ca neighbors, with oxygen, and possibly, Na second-nearest neighbors. EXAFS analyses suggest that Cl sbnd Cl environments may also exist in the glasses in minor amounts. These results are generally consistent with earlier findings for silicate glasses, where Cl - was associated with Ca 2+ and Na + in network modifier sites.

Coupling of Nuclear Waste Form Corrosion and Radionuclide Transports in Presence of Relevant Repository Sediments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wall, Nathalie A.; Neeway, James J.; Qafoku, Nikolla P.

2015-09-30

Assessments of waste form and disposal options start with the degradation of the waste forms and consequent mobilization of radionuclides. Long-term static tests, single-pass flow-through tests, and the pressurized unsaturated flow test are often employed to study the durability of potential waste forms and to help create models that predict their durability throughout the lifespan of the disposal site. These tests involve the corrosion of the material in the presence of various leachants, with different experimental designs yielding desired information about the behavior of the material. Though these tests have proved instrumental in elucidating various mechanisms responsible for material corrosion,more » the chemical environment to which the material is subject is often not representative of a potential radioactive waste repository where factors such as pH and leachant composition will be controlled by the near-field environment. Near-field materials include, but are not limited to, the original engineered barriers, their resulting corrosion products, backfill materials, and the natural host rock. For an accurate performance assessment of a nuclear waste repository, realistic waste corrosion experimental data ought to be modeled to allow for a better understanding of waste form corrosion mechanisms and the effect of immediate geochemical environment on these mechanisms. Additionally, the migration of radionuclides in the resulting chemical environment during and after waste form corrosion must be quantified and mechanisms responsible for migrations understood. The goal of this research was to understand the mechanisms responsible for waste form corrosion in the presence of relevant repository sediments to allow for accurate radionuclide migration quantifications. The rationale for this work is that a better understanding of waste form corrosion in relevant systems will enable increased reliance on waste form performance in repository environments and potentially decrease the need for expensive engineered barriers.Our current work aims are 1) quantifying and understanding the processes associated with glass alteration in contact with Fe-bearing materials; 2) quantifying and understanding the processes associated with glass alteration in presence of MgO (example of engineered barrier used in WIPP); 3) identifying glass alteration suppressants and the processes involved to reach glass alteration suppression; 4) quantifying and understanding the processes associated with Saltstone and Cast Stone (SRS and Hanford cementitious waste forms) in various representative groundwaters; 5) investigating positron annihilation as a new tool for the study of glass alteration; and 6) quantifying and understanding the processes associated with glass alteration under gamma irradiation.« less

ELIMINATION OF THE CHARACTERIZATION OF DWPF POUR STREAM SAMPLE AND THE GLASS FABRICATION AND TESTING OF THE DWPF SLUDGE BATCH QUALIFICATION SAMPLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amoroso, J.; Peeler, D.; Edwards, T.

2012-05-11

A recommendation to eliminate all characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification sample was made by a Six-Sigma team chartered to eliminate non-value-added activities for the Defense Waste Processing Facility (DWPF) sludge batch qualification program and is documented in the report SS-PIP-2006-00030. That recommendation was supported through a technical data review by the Savannah River National Laboratory (SRNL) and is documented in the memorandums SRNL-PSE-2007-00079 and SRNL-PSE-2007-00080. At the time of writing those memorandums, the DWPF was processing sludge-only waste but, has since transitioned to a coupledmore » operation (sludge and salt). The SRNL was recently tasked to perform a similar data review relevant to coupled operations and re-evaluate the previous recommendations. This report evaluates the validity of eliminating the characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification samples based on sludge-only and coupled operations. The pour stream sample has confirmed the DWPF's ability to produce an acceptable waste form from Slurry Mix Evaporator (SME) blending and product composition/durability predictions for the previous sixteen years but, ultimately the pour stream analysis has added minimal value to the DWPF's waste qualification strategy. Similarly, the information gained from the glass fabrication and PCT of the sludge batch qualification sample was determined to add minimal value to the waste qualification strategy since that sample is routinely not representative of the waste composition ultimately processed at the DWPF due to blending and salt processing considerations. Moreover, the qualification process has repeatedly confirmed minimal differences in glass behavior from actual radioactive waste to glasses fabricated from simulants or batch chemicals. In contrast, the variability study has significantly added value to the DWPF's qualification strategy. The variability study has evolved to become the primary aspect of the DWPF's compliance strategy as it has been shown to be versatile and capable of adapting to the DWPF's various and diverse waste streams and blending strategies. The variability study, which aims to ensure durability requirements and the PCT and chemical composition correlations are valid for the compositional region to be processed at the DWPF, must continue to be performed. Due to the importance of the variability study and its place in the DWPF's qualification strategy, it will also be discussed in this report. An analysis of historical data and Production Records indicated that the recommendation of the Six Sigma team to eliminate all characterization of pour stream glass samples and the glass fabrication and PCT performed with the qualification glass does not compromise the DWPF's current compliance plan. Furthermore, the DWPF should continue to produce an acceptable waste form following the remaining elements of the Glass Product Control Program; regardless of a sludge-only or coupled operations strategy. If the DWPF does decide to eliminate the characterization of pour stream samples, pour stream samples should continue to be collected for archival reasons, which would allow testing to be performed should any issues arise or new repository test methods be developed.« less

Leaching assessments of toxic metals in waste plasma display panel glass.

PubMed

Chen, Mengjun; Jiang, Pengfei; Chen, Haiyan; Ogunseitan, Oladele A; Li, Yungui

2015-06-01

The plasma display panel (PDP) is rapidly becoming obsolete, contributing in large amounts to the electronic waste stream. In order to assess the potential for environmental pollution due to hazardous metals leached from PDP glass, standardized leaching procedures, chemical speciation assessments, and bioavailability tests were conducted. According to the Toxicity Characteristic Leaching Procedure (TCLP), arsenic in back glass was present at 4.46 ± 0.22 mg/L, close to its regulation limit of 5 mg/L. Zn is not available in the TCLP, but its TCLP leaching concentration in back glass is 102.96 ± 5.34 mg/L. This is because more than 90% of Zn is in the soluble and exchangeable and carbonate fraction. We did not detect significant levels of Ag, Ba, or Cu in the TCLP leachate, and the main fraction of Ag and Ba is residual, more than 95%, while the fraction distribution of Cu changes SEP by SEP. Ethylenediamine tetraacetic acid (EDTA)- and diethylenetriamine pentaacetic acid (DTPA)-extractable Ag, As, Ba, Cu, Zn, and Ni indicate a lower biohazards potential. These results show that, according to the EPA regulations, PDP glass may not be classified as hazardous waste because none of the metals exceeded their thresholds in PDP leachate. However, the concentrations of As and Zn should be lowered in the manufacturing process and finished product to avoid potential pollution problems. The plasma display panel is rapidly becoming obsolete because of the liquid crystal display. In this study, the leachability of heavy metals contained in the waste plasma display panel glass was first examined by standardized leaching tests, typical chemical speciation assessments, and bioavailability tests, providing fundamental data for waste PDP glass recovery, recycling, and reuse.

Support for HLW Direct Feed - Phase 2, VSL-15R3440-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matlack, K. S.; Pegg, I.; Joseph, I.

This report describes work performed to develop and test new glass and feed formulations originating from a potential flow-sheet for the direct vitrification of High Level Waste (HLW) with minimal or no pretreatment. In the HLW direct feed option that is under consideration for early operations at the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the pretreatment facility would be bypassed in order to support an earlier start-up of the vitrification facility. For HLW, this would mean that the ultrafiltration and caustic leaching operations that would otherwise have been performed in the pretreatment facility would either not be performedmore » or would be replaced by an interim pretreatment function (in-tank leaching and settling, for example). These changes would likely affect glass formulations and waste loadings and have impacts on the downstream vitrification operations. Modification of the pretreatment process may result in: (i) Higher aluminum contents if caustic leaching is not performed; (ii) Higher chromium contents if oxidative leaching is not performed; (iii) A higher fraction of supernate in the HLW feed resulting from the lower efficiency of in-tank washing; and (iv) A higher water content due to the likely lower effectiveness of in-tank settling compared to ultrafiltration. The HLW direct feed option has also been proposed as a potential route for treating HLW streams that contain the highest concentrations of fast-settling plutoniumcontaining particles, thereby avoiding some of the potential issues associated with such particles in the WTP Pretreatment facility [1]. In response, the work presented herein focuses on the impacts of increased supernate and water content on wastes from one of the candidate source tanks for the direct feed option that is high in plutonium.« less

RHENIUM SOLUBILITY IN BOROSILICATE NUCLEAR WASTE GLASS IMPLICATIONS FOR THE PROCESSING AND IMMOBILIZATION OF TECHNETIUM-99 (AND SUPPORTING INFORMATION WITH GRAPHICAL ABSTRACT)

DOE Office of Scientific and Technical Information (OSTI.GOV)

AA KRUGER; A GOEL; CP RODRIGUEZ

2012-08-13

The immobilization of 99Tc in a suitable host matrix has proved a challenging task for researchers in the nuclear waste community around the world. At the Hanford site in Washington State in the U.S., the total amount of 99Tc in low-activity waste (LAW) is {approx} 1,300 kg and the current strategy is to immobilize the 99Tc in borosilicate glass with vitrification. In this context, the present article reports on the solubility and retention of rhenium, a nonradioactive surrogate for 99Tc, in a LAW sodium borosilicate glass. Due to the radioactive nature of technetium, rhenium was chosen as a simulant becausemore » of previously established similarities in ionic radii and other chemical aspects. The glasses containing target Re concentrations varying from 0 to10,000 ppm by mass were synthesized in vacuum-sealed quartz ampoules to minimize the loss of Re by volatilization during melting at 1000 DC. The rhenium was found to be present predominantly as Re7 + in all the glasses as observed by X-ray absorption near-edge structure (XANES). The solubility of Re in borosilicate glasses was determined to be {approx}3,000 ppm (by mass) using inductively coupled plasma-optical emission spectroscopy (ICP-OES). At higher rhenium concentrations, some additional material was retained in the glasses in the form of alkali perrhenate crystalline inclusions detected by X-ray diffraction (XRD) and laser ablation-ICP mass spectrometry (LA-ICP-MS). Assuming justifiably substantial similarities between Re7 + and Tc 7+ behavior in this glass system, these results implied that the processing and immobilization of 99Tc from radioactive wastes should not be limited by the solubility of 99Tc in borosilicate LAW glasses.« less

Extraction of heavy metal (Ba, Sr) and high silica glass powder synthesis from waste CRT panel glasses by phase separation.

PubMed

Xing, Mingfei; Wang, Jingyu; Fu, Zegang; Zhang, Donghui; Wang, Yaping; Zhang, Zhiyuan

2018-04-05

In this study, a novel process for the extraction of heavy metal Ba and Sr from waste CRT panel glass and synchronous preparation of high silica glass powder was developed by glass phase separation. CRT panel glass was first remelted with B 2 O 3 under air atmosphere to produce alkali borosilicate glass. During the phase separation process, the glass separated into two interconnected phases which were B 2 O 3 -rich phase and SiO 2 -rich phase. Most of BaO, SrO and other metal oxides including Na 2 O, K 2 O, Al 2 O 3 and CaO were mainly concentrated in the B 2 O 3 -rich phase. The interconnected B 2 O 3 -rich phase can be completely leached out by 5mol/L HNO 3 at 90 ℃. The remaining SiO 2 -rich phase was porous glasses consisting almost entirely of silica. The maximum Ba and Sr removal rates were 98.84% and 99.38% and high silica glass powder (SiO 2 purity > 90 wt%) was obtained by setting the temperature, B 2 O 3 added amount and holding time at 1000-1100 ℃, 20-30% and 30 min, respectively. Thus this study developed an potential economical process for detoxification and reclamation of waste heavy metal glasses. Copyright © 2017 Elsevier B.V. All rights reserved.

Rhenium Solubility in Borosilicate Nuclear Waste Glass: Implications for the Processing and Immobilization of Technetium-99

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCloy, John S.; Riley, Brian J.; Goel, Ashutosh

2012-10-26

The immobilization of 99Tc in a suitable host matrix has proved to be an arduous task for the researchers in nuclear waste community around the world. At the Hanford site in Washington State, the total amount of 99Tc in low-activity waste (LAW) is ~1300 kg and the current strategy is to immobilize the 99Tc in borosilicate glass with vitrification. In this context, the present article reports on the solubility/retention of rhenium, a nonradioactive surrogate for 99Tc, in a LAW borosilicate glass. Due to the radioactive nature of technetium, rhenium was chosen as a simulant because of the similarity between theirmore » ionic radii and other chemical aspects. The glasses containing Re (0 – 10,000 ppm by mass) were synthesized in vacuum-sealed quartz ampoules in order to minimize the loss of Re by volatilization during melting at 1000 °C. The rhenium was found to predominantly exist as Re (VII) in all the glasses as observed by X-ray absorption near-edge structure (XANES). The solubility of Re in borosilicate glasses was determined to be ~3000 ppm (by mass) with inductively coupled plasma-optical emission spectroscopy (ICP-OES). At higher rhenium concentrations, some additional material was retained in the glasses in the form of crystalline inclusions that were detected by X-ray diffraction (XRD) and laser ablation-ICP mass spectrometry (LA-ICP-MS). The implications of these results on the immobilization of 99Tc from radioactive wastes in borosilicate glasses have been discussed.« less

Long-term high-level waste technology. Composite report

NASA Astrophysics Data System (ADS)

Cornman, W. R.

1981-12-01

Research and development studies on the immobilization of high-level wastes from the chemical reprocessing of nuclear reactor fuels are summarized. The reports are grouped under the following tasks: (1) program management and support; (2) waste preparation; (3) waste fixation; and (4) final handling. Some of the highlights are: leaching properties were obtained for titanate and tailored ceramic materials being developed at ICPP to immobilize zirconia calcine; comparative leach tests, hot-cell tests, and process evaluations were conducted of waste form alternatives to borosilicate glass for the immobilization of SRP high-level wastes, experiments were run at ANL to qualify neutron activation analysis and radioactive tracers for measuring leach rates from simulated waste glasses; comparative leach test samples of SYNROC D were prepared, characterized, and tested at LLNL; encapsulation of glass marbles with lead or lead alloys was demonstrated on an engineering scale at PNL; a canister for reference Commercial HLW was designed at PNL; a study of the optimization of salt-crete was completed at SRL; a risk assessment showed that an investment for tornado dampers in the interim storage building of the DWPF is unjustified.

Description of Defense Waste Processing Facility reference waste form and canister. Revision 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baxter, R.G.

1983-08-01

The Defense Waste Processing Facility (DWPF) will be located at the Savannah River Plant in Aiken, SC, and is scheduled for construction authorization during FY-1984. The reference waste form is borosilicate glass containing approx. 28 wt % sludge oxides, with the balance glass frit. Borosilicate glass was chosen because of its high resistance to leaching by water, its relatively high solubility for nuclides found in the sludge, and its reasonably low melting temperature. The glass frit contains about 58% SiO/sub 2/ and 15% B/sub 2/O/sub 3/. Leachabilities of SRP waste glasses are expected to approach 10/sup -8/ g/m/sup 2/-day basedmore » upon 1000-day tests using glasses containing SRP radioactive waste. Tests were performed under a wide variety of conditions simulating repository environments. The canister is filled with 3260 lb of glass which occupies about 85% of the free canister volume. The filled canister will generate approx. 470 watts when filled with oxides from 5-year-old sludge and 15-year-old supernate from the sludge and supernate processes. The radionuclide content of the canister is about 177,000 ci, with a radiation level of 5500 rem/h at canister surface contact. The reference canister is fabricated of standard 24-in.-OD, Schedule 20, 304L stainless steel pipe with a dished bottom, domed head, and a combined lifting and welding flange on the head neck. The overall canister length is 9 ft 10 in. with a 3/8-in. wall thickness. The 3-m canister length was selected to reduce equipment cell height in the DWPF to a practical size. The canister diameter was selected as an optimum size from glass quality considerations, a logical size for repository handling and to ensure that a filled canister with its double containment shipping cask could be accommodated on a legal-weight truck. The overall dimensions and weight appear to be compatible with preliminary assessments of repository requirements. 10 references.« less

Hydrogen speciation in hydrated layers on nuclear waste glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aines, R.D.; Weed, H.C.; Bates, J.K.

1987-01-15

The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. Molecular water was foundmore » in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 {mu}m layer on SRL-131 glass formed by leaching at 90{sup 0}C contained a total of 4.9 moles/liter of water, 2/3 of which was as hydroxyl. The unreacted bulk glass contains about 0.018 moles/liter water, all as hydroxyl. The amount of hydrogen added to the SRL-131 glass was about 70% of the original Na + Li content, not the 300% that would result from alkali=hydronium ion interdiffusion. If all the hydrogen is then assumed to be added as the result of alkali-H{sup +} interdiffusion, the molecular water observed may have formed from condensation of the original hydroxyl groups.« less

FTIR spectra and properties of iron borophosphate glasses containing simulated nuclear wastes

NASA Astrophysics Data System (ADS)

Liao, Qilong; Wang, Fu; Chen, Kuiru; Pan, Sheqi; Zhu, Hanzhen; Lu, Mingwei; Qin, Jianfa

2015-07-01

30 wt.% simulated nuclear wastes were successfully immobilized by B2O3-doped iron phosphate base glasses. The structure and thermal stability of the prepared wasteforms were characterized by Fourier transform infrared spectroscopy and differential thermal analysis, respectively. The subtle structural variations attributed to different B2O3 doping modes have been discussed in detail. The results show that the thermal stability and glass forming tendency of the iron borophosphate glass wasteforms are faintly affected by different B2O3 doping modes. The main structural networks of iron borophosphate glass wasteforms are PO43-, P2O74-, [BO4] groups. Furthermore, for the wasteform prepared by using 10B2O3-36Fe2O3-54P2O5 as base glass, the distributions of Fe-O-P bonds, [BO4], PO43- and P2O74- groups are optimal. In general, the dissolution rate (DR) values of the studied iron borophosphate wasteforms are about 10-8 g cm-2 min-1. The obtained conclusions can offer some useful information for the disposal of high-level radioactive wastes using boron contained phosphate glasses.

Letter report on PCT/Monolith glass ceramic corrosion tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, Charles L.

2015-09-24

The Savannah River National Laboratory (SRNL) is collaborating with personnel from Pacific Northwest National Laboratory (PNNL) to study advanced waste form glass ceramics for immobilization of waste from Used Nuclear Fuel (UNF) separations processes. The glass ceramic waste forms take advantage of both crystalline and glassy phases where ‘troublesome’ elements (e.g., low solubility in glass or very long-lived) partition to highly durable ceramic phases with the remainder of elements residing in the glassy phase. The ceramic phases are tailored to create certain minerals or unique crystalline structures that can host the radionuclides by binding them in their specific crystalline networkmore » while not adversely impacting the residual glass network (Crum et al., 2011). Glass ceramics have been demonstrated using a scaled melter test performed in a pilot scale (1/4 scale) cold crucible induction melter (CCIM) (Crum et al., 2014; Maio et al., 2015). This report summarizes recent results from both Phase I and Phase II bench scale tests involving crucible fabrication and corrosion testing of glass ceramics using the Product Consistency Test (PCT). Preliminary results from both Phase I and Phase II bench scale tests involving statistically designed matrices have previously been reported (Crawford, 2013; Crawford, 2014).« less

Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses

DOE PAGES

Bingham, Paul A.; Vaishnav, Shuchi; Forder, Sue D.; ...

2016-11-10

In this paper, the capacity of simulated high-level radioactive waste borosilicate glasses to incorporate sulfate has been studied as a function of glass composition. Combined Raman, 57Fe Mössbauer and literature evidence supports the attribution of coordination numbers and oxidation states of constituent cations for the purposes of modelling, and results confirm the validity of correlating sulfate incorporation in multicomponent borosilicate radioactive waste glasses with different models. A strong compositional dependency is observed and this can be described by an inverse linear relationship between incorporated sulfate (mol% SO 4 2-) and total cation field strength index of the glass, Σ(z/a 2),more » with a high goodness-of-fit (R 2 ≈ 0.950). Similar relationships are also obtained if theoretical optical basicity, Λ th (R 2 ≈ 0.930) or non-bridging oxygen per tetrahedron ratio, NBO/T (R 2 ≈ 0.919), are used. Finally, results support the application of these models, and in particular Σ(z/a 2), as predictive tools to aid the development of new glass compositions with enhanced sulfate capacities.« less

Effects of soda-lime-silica waste glass on mullite formation kinetics and micro-structures development in vitreous ceramics.

PubMed

Marinoni, Nicoletta; D'Alessio, Daniela; Diella, Valeria; Pavese, Alessandro; Francescon, Ferdinando

2013-07-30

The effects of soda-lime waste glass, from the recovery of bottle glass cullet, in partial replacement of Na-feldspar for sanitary-ware ceramic production are discussed. Attention is paid to the mullite growth kinetics and to the macroscopic properties of the final output, the latter ones depending on the developed micro-structures and vitrification grade. Measurements have been performed by in situ high temperature X-ray powder diffraction, scanning electron microscopy, thermal dilatometry, water absorption and mechanical testing. Glass substituting feldspar from 30 to 50 wt% allows one (i) to accelerate the mullite growth reaction kinetics, and (ii) to achieve macroscopic features of the ceramic output that comply with the latest technical requirements. The introduction of waste glass leads to (i) a general saving of fuel and reduction of the CO2-emissions during the firing stage, (ii) a preservation of mineral resources in terms of feldspars, and (iii) an efficient management of the bottle glass refuse by readdressing a part of it in the sanitary-ware manufacturing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Lead recovery from waste CRT funnel glass by high-temperature melting process.

PubMed

Hu, Biao; Hui, Wenlong

2018-02-05

In this research, a novel and effective process for waste CRT funnel glass treatment was developed. The key to this process is removal of lead from the CRT funnel glass by high-temperature melting process. Sodium carbonate powder was used as a fusion agent, sodium sulfide serves as a catalytic agent and carbon powder acts as reducing agent. Experimental results showed that lead recovery rate increased with an increase in the amount of added sodium carbonate, sodium sulfide, carbonate, temperature and holding time initially, and then reached a stable value. The maximum lead recovery rate was approximately 94%, when the optimum adding amount of sodium carbonate, sodium sulfide, carbonate, temperature and holding time were 25%, 8%, 3.6%, 1200°C and 120min, respectively. In the high-temperature melting process, lead silicate in the funnel glass was firstly reduced, and then removed. The glass slag can be made into sodium and potassium silicate by hydrolysis process. This study proposed a practical and economical process for recovery of lead and utilization of waste glass slag. Copyright © 2017 Elsevier B.V. All rights reserved.

Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bingham, P. A.; Vaishnav, S.; Forder, S. D.

2017-02-01

The capacity of simulated high-level radioactive waste borosilicate glasses to incorporate sulfate has been studied as a function of glass composition. Combined Raman, 57Fe Mössbauer and literature evidence supports the attribution of coordination numbers and oxidation states of constituent cations for the purposes of modelling, and results confirm the validity of correlating sulfate incorporation in multicomponent borosilicate radioactive waste glasses with different models. A strong compositional dependency is observed and this can be described by an inverse linear relationship between incorporated sulfate (mol% SO 4 2-) and total cation field strength index of the glass, Σ(z/a 2), with a highmore » goodness-of-fit (R 2 ≈ 0.950). Similar relationships are also obtained if theoretical optical basicity, Λ th (R 2 ≈ 0.930) or non-bridging oxygen per tetrahedron ratio, NBO/T (R 2 ≈ 0.919), are used. Results support the application of these models, and in particular Σ(z/a 2), as predictive tools to aid the development of new glass compositions with enhanced sulfate capacities.« less

Examination of pulverized waste recycled glass as filter media in slow sand filtration. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piccirillo, J.B.; Letterman, R.D.

1997-10-01

The purpose of this study was to investigate the pulverization of waste recycled glass to produce glass sand for slow sand filters. Pulverization experiments were performed using a fail mill pulverizer. The glass sand product from the pulverizer meets the size distribution requirements of ASTM-C-33 without size distribution adjustment. The size distribution must be adjusted to meet the grain size distribution requirements of the Ten States Standards and the USEPA for filter media used in slow sand filters. Pulverized glass that meet slow sand filter media specifications is an effective alternative to silica sand as a filter media for slowmore » sand filtration. Three pilot plant slow sand filters with glass sand filter media were compared to a fourth filter containing silica sand filter media. Over an 8 month period of continuous operation, the performance of the glass sand filter media was as good or better than the silica sands, with removals of 56% to 96% for turbidity; 99.78% to 100.0% for coliform bacteria; 99.995% to 99.997% for giardia cysts; 99.92% and 99.97% for cryptosporidium oocysts. Based on a cost-benefit analysis, converting waste glass into filter media may be economically advantageous for recycling facilities.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Edwards, T. B.

In this report, the Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for 14 simulated high level waste glasses fabricated by the Pacific Northwest National Laboratory. The results of these analyses will be used as part of efforts to revise or extend the validation regions of the current Hanford Waste Treatment and Immobilization Plant glass property models to cover a broader span of waste compositions. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. All of the measured sums of oxides for the study glassesmore » fell within the interval of 96.9 to 100.8 wt %, indicating recovery of all components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %. The PCT results were normalized to both the targeted and measured compositions of the study glasses. Several of the glasses exhibited increases in normalized concentrations (NCi) after the canister centerline cooled (CCC) heat treatment. Five of the glasses, after the CCC heat treatment, had NC B values that exceeded that of the Environmental Assessment (EA) benchmark glass. These results can be combined with additional characterization, including X-ray diffraction, to determine the cause of the higher release rates.« less

Molecular Dynamics-based Simulations of Bulk/Interfacial Structures and Diffusion Behaviors in Nuclear Waste Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Jincheng; Rimsza, Jessica; Deng, Lu

This NEUP Project aimed to generate accurate atomic structural models of nuclear waste glasses by using large-scale molecular dynamics-based computer simulations and to use these models to investigate self-diffusion behaviors, interfacial structures, and hydrated gel structures formed during dissolution of these glasses. The goal was to obtain realistic and accurate short and medium range structures of these complex oxide glasses, to provide a mechanistic understanding of the dissolution behaviors, and to generate reliable information with predictive power in designing nuclear waste glasses for long-term geological storage. Looking back of the research accomplishments of this project, most of the scientific goalsmore » initially proposed have been achieved through intensive research in the three and a half year period of the project. This project has also generated a wealth of scientific data and vibrant discussions with various groups through collaborations within and outside of this project. Throughout the project one book chapter and 14 peer reviewed journal publications have been generated (including one under review) and 16 presentations (including 8 invited talks) have been made to disseminate the results of this project in national and international conference. Furthermore, this project has trained several outstanding graduate students and young researchers for future workforce in nuclear related field, especially on nuclear waste immobilization. One postdoc and four PhD students have been fully or partially supported through the project with intensive training in the field material science and engineering with expertise on glass science and nuclear waste disposal« less

Effect of Silica Particle Size of Nuclear Waste-to-Glass Conversion - 17319

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dixon, Derek R.; Cutforth, Derek A.; Vanderveer, Bradley J.

The process for converting nuclear waste-to-glass in an electric melter occurs in the cold cap, a crust of reacting solids floating on the glass pool. As the melter feed (a mixture of the nuclear waste and glass forming and modifying additives) heats up in the cold cap, glass-forming reactions ensue, causing the feed matrix to connect, trapping reaction gases to create a foam layer. The foam layer reduces the rate of melting by separating the reacting feed from the melt pool. The size of the silica particle additives in the melter feed affects melt viscosity and, hence, foam stability. Tomore » investigate this effect, seven nuclear waste simulant feeds of a high-level waste were batched as slurries and prepared with dissimilar ranges of silica particle size. Each slurry feed was charged into a laboratory-scale melter (LSM) to produce a cold cap and the propensity of feeds to foam was determined by pressing dried feeds into pellets and monitoring the change of pellet volume in response to heating. Two of these slurries were designed to have dissimilar glass viscosities at 1150°C. In the low temperature region of the cold cap, before the melter feed connects, the feeds without fine silica particles behaved similar to the high viscosity feed as their volume contracted while the feed with silica particles no larger than 5 µm reacted like the low viscosity feed. However, the feed volume similarities reversed as the feed connected and expanded through the foam region of the cold cap.« less

Extraction of lead from waste CRT funnel glass by generating lead sulfide - An approach for electronic waste management.

PubMed

Hu, Biao; Hui, Wenlong

2017-09-01

Waste cathode ray tube (CRT) funnel glass is the key and difficult points in waste electrical and electronic equipment (WEEE) disposal. In this paper, a novel and effective process for the detoxification and reutilization of waste CRT funnel glass was developed by generating lead sulfide precipitate via a high-temperature melting process. The central function in this process was the generation of lead sulfide, which gathered at the bottom of the crucible and was then separated from the slag. Sodium carbonate was used as a flux and reaction agent, and sodium sulfide was used as a precipitating agent. The experimental results revealed that the lead sulfide recovery rate initially increased with an increase in the amount of added sodium carbonate, the amount of sodium sulfide, the temperature, and the holding time and then reached an equilibrium value. The maximum lead sulfide recovery rate was approximately 93%, at the optimum sodium carbonate level, sodium sulfide level, temperature, and holding time of 25%, 8%, 1200°C, and 2h, respectively. The glass slag can be made into sodium and potassium silicate by hydrolysis in an environmental and economical process. Copyright © 2017 Elsevier Ltd. All rights reserved.

The grout/glass performance assessment code system (GPACS) with verification and benchmarking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piepho, M.G.; Sutherland, W.H.; Rittmann, P.D.

1994-12-01

GPACS is a computer code system for calculating water flow (unsaturated or saturated), solute transport, and human doses due to the slow release of contaminants from a waste form (in particular grout or glass) through an engineered system and through a vadose zone to an aquifer, well and river. This dual-purpose document is intended to serve as a user`s guide and verification/benchmark document for the Grout/Glass Performance Assessment Code system (GPACS). GPACS can be used for low-level-waste (LLW) Glass Performance Assessment and many other applications including other low-level-waste performance assessments and risk assessments. Based on all the cses presented, GPACSmore » is adequate (verified) for calculating water flow and contaminant transport in unsaturated-zone sediments and for calculating human doses via the groundwater pathway.« less

Radioactive waste material disposal

DOEpatents

Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

1995-10-24

The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

Radioactive waste material disposal

DOEpatents

Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

1995-01-01

The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

Ion Exchange Distribution Coefficient Tests and Computer Modeling at High Ionic Strength Supporting Technetium Removal Resin Maturation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nash, Charles A.; Hamm, L. Larry; Smith, Frank G.

2014-12-19

The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant (WTP) that is currently under construction. The baseline plan for this facility is to treat the waste, splitting it into High Level Waste (HLW) and Low Activity Waste (LAW). Both waste streams are then separately vitrified as glass and poured into canisters for disposition. The LAW glass will be disposed onsite in the Integrated Disposal Facility (IDF). There are currently no plans to treat the waste to remove technetium, so its disposition path is the LAW glass. Duemore » to the water solubility properties of pertechnetate and long half-life of 99Tc, effective management of 99Tc is important to the overall success of the Hanford River Protection Project mission. To achieve the full target WTP throughput, additional LAW immobilization capacity is needed, and options are being explored to immobilize the supplemental LAW portion of the tank waste. Removal of 99Tc, followed by off-site disposal, would eliminate a key risk contributor for the IDF Performance Assessment (PA) for supplemental waste forms, and has potential to reduce treatment and disposal costs. Washington River Protection Solutions (WRPS) is developing some conceptual flow sheets for supplemental LAW treatment and disposal that could benefit from technetium removal. One of these flowsheets will specifically examine removing 99Tc from the LAW feed stream to supplemental immobilization. To enable an informed decision regarding the viability of technetium removal, further maturation of available technologies is being performed. This report contains results of experimental ion exchange distribution coefficient testing and computer modeling using the resin SuperLig ® 639 a to selectively remove perrhenate from high ionic strength simulated LAW. It is advantageous to operate at higher concentration in order to treat the waste stream without dilution and to minimize the volume of the final wasteform. This work examined the impact of high ionic strength, high density, and high viscosity if higher concentration LAW feed solution is used. Perrhenate (ReO 4 -) has been shown to be a good nonradioactive surrogate for pertechnetate in laboratory testing for this ion exchange resin, and the performance bias is well established. Equilibrium contact testing with 7.8 M [Na +] average simulant concentrations indicated that the SuperLig ® 639 resin average perrhenate distribution coefficient was 368 mL/g at a 100:1 phase ratio. Although this indicates good performance at high ionic strength, an equilibrium test cannot examine the impact of liquid viscosity, which impacts the diffusivity of ions and therefore the loading kinetics. To get an understanding of the effect of diffusivity, modeling was performed, which will be followed up with column tests in the future.« less

Letter Report: LAW Simulant Development for Cast Stone Screening Test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, Renee L.; Westsik, Joseph H.; Swanberg, David J.

2013-03-27

More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in themore » HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second facility will be needed for the expected volume of additional LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with waste acceptance criteria for the IDF disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long term performance of the waste form in the IDF disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF. A testing program was developed in fiscal year (FY) 2012 describing in some detail the work needed to develop and qualify Cast Stone as a waste form for the solidification of Hanford LAW (Westsik et al. 2012). Included within Westsik et al. (2012) is a section on the near-term needs to address Tri-Party Agreement Milestone M-062-40ZZ. The objectives of the testing program to be conducted in FY 2013 and FY 2014 are to: • Determine an acceptable formulation for the LAW Cast Stone waste form. • Evaluate sources of dry materials for preparing the LAW Cast Stone. • Demonstrate the robustness of the Cast Stone waste form for a range of LAW compositions. • Demonstrate the robustness of the formulation for variability in the Cast Stone process. • Provide Cast Stone contaminant release data for PA and risk assessment evaluations. The first step in determining an acceptable formulation for the LAW Cast Stone waste form is to conduct screening tests to examine expected ranges in pretreated LAW composition, waste stream concentrations, dry-materials sources, and mix ratios of waste feed to dry blend. A statistically designed test matrix will be used to evaluate the effects of these key parameters on the properties of the Cast Stone as it is initially prepared and after curing. The second phase of testing will focus on selection of a baseline Cast Stone formulation for LAW and demonstrating that Cast Stone can meet expected waste form requirements for disposal in the IDF. It is expected that this testing will use the results of the screening tests to define a smaller suite of tests to refine the composition of the baseline Cast Stone formulation (e.g. waste concentration, water to dry mix ratio, waste loading).« less

Influence of coatings on the thermal and mechanical processes at insulating glass units

NASA Astrophysics Data System (ADS)

Penkova, Nina; Krumov, Kalin; Surleva, Andriana; Geshkova, Zlatka

2017-09-01

Different coatings on structural glass are used in the advances transparent facades and window systems in order to increase the thermal performance of the glass units and to regulate their optical properties. Coated glass has a higher absorptance in the solar spectrum which leads to correspondent higher temperature in the presence of solar load compared to the uncoated one. That process results in higher climatic loads at the insulating glass units (IGU) and in thermal stresses in the coated glass elements. Temperature fields and gradients in glass panes and climatic loads at IGU in window systems are estimated at different coating of glazed system. The study is implemented by numerical simulation of conjugate heat transfer in the window systems at summer time and presence of solar irradiation, as well as during winter night time.

Definition of an Acceptable Glass composition Region (AGCR) via an Index System and a Partitioning Function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peeler, D. K.; Taylor, A. S.; Edwards, T.B.

2005-06-26

The objective of this investigation was to appeal to the available ComPro{trademark} database of glass compositions and measured PCTs that have been generated in the study of High Level Waste (HLW)/Low Activity Waste (LAW) glasses to define an Acceptable Glass Composition Region (AGCR). The term AGCR refers to a glass composition region in which the durability response (as defined by the Product Consistency Test (PCT)) is less than some pre-defined, acceptable value that satisfies the Waste Acceptance Product Specifications (WAPS)--a value of 10 g/L was selected for this study. To assess the effectiveness of a specific classification or index systemmore » to differentiate between acceptable and unacceptable glasses, two types of errors (Type I and Type II errors) were monitored. A Type I error reflects that a glass with an acceptable durability response (i.e., a measured NL [B] < 10 g/L) is classified as unacceptable by the system of composition-based constraints. A Type II error occurs when a glass with an unacceptable durability response is classified as acceptable by the system of constraints. Over the course of the efforts to meet this objective, two approaches were assessed. The first (referred to as the ''Index System'') was based on the use of an evolving system of compositional constraints which were used to explore the possibility of defining an AGCR. This approach was primarily based on ''glass science'' insight to establish the compositional constraints. Assessments of the Brewer and Taylor Index Systems did not result in the definition of an AGCR. Although the Taylor Index System minimized Type I errors which allowed access to composition regions of interest to improve melt rate or increase waste loadings for DWPF as compared to the current durability model, Type II errors were also committed. In the context of the application of a particular classification system in the process control system, Type II errors are much more serious than Type I errors. A Type I error only reflects that the particular constraint system being used is overly conservative (i.e., its application restricts access to glasses that have an acceptable measured durability response). A Type II error results in a more serious misclassification that could result in allowing the transfer of a Slurry Mix Evaporator (SME) batch to the melter, which is predicted to produce a durable product based on the specific system applied but in reality does not meet the defined ''acceptability'' criteria. More specifically, a nondurable product could be produced in DWPF. Given the presence of Type II errors, the Index System approach was deemed inadequate for further implementation consideration at the DWPF. The second approach (the JMP partitioning process) was purely data driven and empirically derived--glass science was not a factor. In this approach, the collection of composition--durability data in ComPro was sequentially partitioned or split based on the best available specific criteria and variables. More specifically, the JMP software chose the oxide (Al{sub 2}O{sub 3} for this dataset) that most effectively partitions the PCT responses (NL [B]'s)--perhaps not 100% effective based on a single oxide. Based on this initial split, a second request was made to split a particular set of the ''Y'' values (good or bad PCTs based on the 10 g/L limit) based on the next most critical ''X'' variable. This ''splitting'' or ''partitioning'' process was repeated until an AGCR was defined based on the use of only 3 oxides (Al{sub 2}O{sub 3}, CaO, and MgO) and critical values of > 3.75 wt% Al{sub 2}O{sub 3}, {ge} 0.616 wt% CaO, and < 3.521 wt% MgO. Using this set of criteria, the ComPro database was partitioned in which no Type II errors were committed. The automated partitioning function screened or removed 978 of the 2406 ComPro glasses which did cause some initial concerns regarding excessive conservatism regardless of its ability to identify an AGCR. However, a preliminary review of glasses within the 1428 ''acceptable'' glasses defining the ACGR includes glass systems of interest to support the accelerated mission.« less

SUMMARY OF 2010 DOE EM INTERNATIONAL PROGRAM STUDIES OF WASTE GLASS STRUCTURE AND PROPERTIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Choi, A.; Marra, J.

2011-02-07

Collaborative work between the Savannah River National Laboratory (SRNL) and SIA Radon in Russia was divided among three tasks for calendar year 2010. The first task focused on the study of simplified high level waste glass compositions with the objective of identifying the compositional drivers that lead to crystallization and poor chemical durability. The second task focused on detailed characterization of more complex waste glass compositions with unexpectedly poor chemical durabilities. The third task focused on determining the structure of select high level waste glasses made with varying frit compositions in order to improve models under development for predicting themore » melt rate of the Defense Waste Processing Facility (DWPF) glasses. The majority of these tasks were carried out at SIA Radon. Selection and fabrication of the glass compositions, along with chemical composition measurements and evaluations of durability were carried out at SRNL and are described in this report. SIA Radon provided three summary reports based on the outcome of the three tasks. These reports are included as appendices to this document. Briefly, the result of characterization of the Task 1 glasses may indicate that glass compositions where iron is predominantly tetrahedrally coordinated have more of a tendency to crystallize nepheline or nepheline-like phases. For the Task 2 glasses, the results suggested that the relatively low fraction of tetrahedrally coordinated boron and the relatively low concentrations of Al{sub 2}O{sub 3} available to form [BO{sub 4/2}]{sup -}Me{sup +} and [AlO{sub 4/2}]{sup -}Me{sup +} tetrahedral units are not sufficient to consume all of the alkali ions, and thus these alkali ions are easily leached from the glasses. All of the twelve Task 3 glass compositions were determined to be mainly amorphous, with some minor spinel phases. Several key structural units such as metasilicate chains and rings were identified, which confirms the current modeling approach for the silicate phase. The coordination of aluminum and iron was found to be mainly tetrahedral, with some octahedral iron ions. In all samples, trigonally-coordinated boron was determined to dominate over tetrahedrally-coordinated boron. The results further suggested that BO{sub 4} tetrahedra and BO{sub 3} triangles form complex borate units and may be present as separate constituents. However, no quantification of tetrahedral-to-trigonal boron ratio was made.« less

Use of selected waste materials in concrete mixes.

PubMed

Batayneh, Malek; Marie, Iqbal; Asi, Ibrahim

2007-01-01

A modern lifestyle, alongside the advancement of technology has led to an increase in the amount and type of waste being generated, leading to a waste disposal crisis. This study tackles the problem of the waste that is generated from construction fields, such as demolished concrete, glass, and plastic. In order to dispose of or at least reduce the accumulation of certain kinds of waste, it has been suggested to reuse some of these waste materials to substitute a percentage of the primary materials used in the ordinary portland cement concrete (OPC). The waste materials considered to be recycled in this study consist of glass, plastics, and demolished concrete. Such recycling not only helps conserve natural resources, but also helps solve a growing waste disposal crisis. Ground plastics and glass were used to replace up to 20% of fine aggregates in concrete mixes, while crushed concrete was used to replace up to 20% of coarse aggregates. To evaluate these replacements on the properties of the OPC mixes, a number of laboratory tests were carried out. These tests included workability, unit weight, compressive strength, flexural strength, and indirect tensile strength (splitting). The main findings of this investigation revealed that the three types of waste materials could be reused successfully as partial substitutes for sand or coarse aggregates in concrete mixtures.

In vitro wear rates of materials under different loads and varying pH.

PubMed

Shabanian, Mitra; Richards, Lindsay C

2002-06-01

Despite the need for information about the wear characteristics of restorative materials, there have been few systemic studies of the factors that influence the rate of material wear. This study compared the wear rates of enamel and 3 tooth-colored restorative materials under different loads (0, 3.2, 6.7, and 9.95 kg) and pH levels (1.2, 3.3, and 7.0). An electromechanical tooth wear machine was used so that standard restorations representing 3 materials could be worn by opposing enamel under controlled conditions. The wear rates of enamel, composite (Z100), a conventional glass ionomer cement (Fuji IX), and a resin-modified glass ionomer cement (Fuji II LC) were compared at a range of loads (0 to 9.95 kg) and pH levels (1.2 to 7.0) and also at different sites across each restoration. Ten specimens were randomly assigned to each experimental group. Wear assessment was performed with a modified light microscope to quantify the height changes at defined points across wear facets. Four-way analysis of variance was used to compare wear rates among materials, pH levels, loads, and sites. Post-hoc t tests identified significant differences between specific pairs of experimental conditions (P<.05). The wear rates of enamel and the other test materials varied significantly with pH (P<.0001), load (P<.0001), and type of material (P<.0001). Enamel wear was influenced most by varied pH, whereas the composite was least affected by acid. The conventional glass ionomer cement was more susceptible than the composite to the effects of varied pH; the acid susceptibility of the resin-modified glass ionomer cement was generally between that of the composite and conventional glass ionomer cement. Enamel and the conventional glass ionomer cement were affected similarly by load. The composite was more resistant than the conventional glass ionomer cement to wear at higher loads; the resin-modified glass ionomer cement exhibited intermediate load resistance. Within the limitations of this study, the 3 test materials were more resistant than enamel to acid, with the composite demonstrating the lowest susceptibility to acid. The acid- and load-resistance of the resin-modified glass ionomer cement was consistently less than that of the composite and greater than that of the conventional glass ionomer cement.

Dynamic Loading Characteristics in Metals and Composites

DTIC Science & Technology

2009-12-01

Armenakas and Sciammarella [6] reported experimental findings on the mechanical properties of glass fiber reinforced epoxy plates subjected to high rates... Sciammarella [6] Glass/epoxy Decrease Increase Decrease - Lifshitz [7] Angle ply glass/epoxy Increase Independent Independent - Daniel et al...Armenakas, and C. A. Sciammarella , “Response of glass-fiber-reinforced epoxy specimens to high rates of tensile loading,” Experimental Mechanics, vol

Compositional threshold for Nuclear Waste Glass Durability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, Albert A.; Farooqi, Rahmatullah; Hrma, Pavel R.

2013-04-24

Within the composition space of glasses, a distinct threshold appears to exist that separates "good" glasses, i.e., those which are sufficiently durable, from "bad" glasses of a low durability. The objective of our research is to clarify the origin of this threshold by exploring the relationship between glass composition, glass structure and chemical durability around the threshold region.

Understanding of the mechanical and structural changes induced by alpha particles and heavy ions in the French simulated nuclear waste glass

NASA Astrophysics Data System (ADS)

Karakurt, G.; Abdelouas, A.; Guin, J.-P.; Nivard, M.; Sauvage, T.; Paris, M.; Bardeau, J.-F.

2016-07-01

Borosilicate glasses are considered for the long-term confinement of high-level nuclear wastes. External irradiations with 1 MeV He+ ions and 7 MeV Au5+ ions were performed to simulate effects produced by alpha particles and by recoil nuclei in the simulated SON68 nuclear waste glass. To better understand the structural modifications, irradiations were also carried out on a 6-oxides borosilicate glass, a simplified version of the SON68 glass (ISG glass). The mechanical and macroscopic properties of the glasses were studied as function of the deposited electronic and nuclear energies. Alpha particles and gold ions induced a volume change up to -0.7% and -2.7%, respectively, depending on the glass composition. Nano-indentations tests were used to determine the mechanical properties of the irradiated glasses. A decrease of about -22% to -38% of the hardness and a decrease of the reduced Young's modulus by -8% were measured after irradiations. The evolution of the glass structure was studied by Raman spectroscopy, and also 11B and 27Al Nuclear Magnetic Resonance (MAS-NMR) on a 20 MeV Kr irradiated ISG glass powder. A decrease of the silica network connectivity after irradiation with alpha particles and gold ions is deduced from the structural changes observations. NMR spectra revealed a partial conversion of BO4 to BO3 units but also a formation of AlO5 and AlO6 species after irradiation with Kr ions. The relationships between the mechanical and structural changes are also discussed.

Viscoplasticity of simulated high-level radioactive waste glass containing platinum group metal particles

NASA Astrophysics Data System (ADS)

Uruga, Kazuyoshi; Usami, Tsuyoshi; Tsukada, Takeshi; Komamine, Satoshi; Ochi, Eiji

2014-09-01

The shear rate dependency of the viscosity of three simulated high-level radioactive waste glasses containing 0, 1.2 and 4.5 wt% platinum group metals (PGMs) was examined at a temperature range of 1173-1473 K by a rotating viscometer. Shear stress when the shear rate equals zero, i.e. yield stress, was also measured by capillary method. The viscosity of the glass containing no PGM was shear rate-independent Newtonian fluid. On the other hand, the apparent viscosity of the glasses containing PGMs increased with decreasing shear rate, and nonzero amount of yield stresses were detected from both glasses. The viscosity and yield stress of the glass containing 4.5 wt% PGMs was roughly one to two orders of magnitude greater than the glass containing 1.2 wt% PGMs. These viscoplastic properties were numerically expressed by Casson equation.

Effect of additional materials on the properties of glass-ceramic produced from incinerator fly ashes.

PubMed

Cheng, T W

2004-07-01

There are 21 Metro-waste incinerators in Taiwan under construction and are expected to be finished at year 2003. It is estimated that these incinerators will produce about two million tons of incinerator ash. In order to reduce the volume and eliminate contamination problems, high temperature molten technology studies have been conducted. The purpose of this research was that of trying to control the chemical composition of the glass-ceramic produced from incinerator fly ash, in order to improve the characteristics of the glass-ceramic. The experimental results showed that the additional materials, Mg(OH)2 and waste glass cullet, can change glass-ceramic phases from gehlenite to augite, pigeonite, and diopside. The physical, mechanical and chemical resistance properties of the glass-ceramic also showed much better characteristics than prepared glass-ceramic using incinerator fly ash alone.

Hydrothermal transformations in an aluminophosphate glass matrix containing simulators of high-level radioactive wastes

NASA Astrophysics Data System (ADS)

Yudintsev, S. V.; Mal'kovsky, V. I.; Mokhov, A. V.

2016-05-01

The interaction of aluminophosphate glass with water at 95°C for 35 days results in glass heterogenization and in the appearance of a gel layer and various phases. The leaching rate of elements is low owing to the formation of a protective layer on the glass surface. It is shown that over 80% of uranium leached from the glass matrix occurs as colloids below 450 nm in size characterized by high migration ability in the geological environment. To determine the composition of these colloids is a primary task for further studies. Water vapor is a crystallization factor for glasses. The conditions as such may appear even at early stages of glass storage because of the failure of seals on containers of high-level radioactive wastes. The examination of water resistance of crystallized matrices and determination of the fraction of radionuclide in colloids are also subjects for further studies.

Glass Masonry - Experimental Verification of Bed Joint under Shear

NASA Astrophysics Data System (ADS)

Fíla, J.; Eliášová, M.; Sokol, Z.

2017-10-01

Glass is considered as a traditional material for building industry but was mostly used for glazing of the windows. At present, glass is an integral part of contemporary architecture where glass structural elements such as beams, stairs, railing ribs or columns became popular in the last two decades. However, using glass as structural material started at the beginning of 20th century, when masonry from hollow glass blocks were used. Using solid glass brick is very rare and only a few structures with solid glass bricks walls have been built in the last years. Pillars and walls made from solid glass bricks are mainly loaded by compression and/or bending from the eccentricity of vertical load or wind load. Due to high compressive strength of glass, the limiting factor of the glass masonry is the joint between the glass bricks as the smooth surface requires another type of mortar / glue compared to traditional masonry. Shear resistance and failure modes of brick bed joint was determined during series of tests using various mortars, two types of surface treatment and different thickness of the mortar joint. Shear tests were completed by small scale tests for mortar - determination of flexural and compressive strength of hardened mortar.

The nature, fabrication, and applications of photosensitive, bulk, germano-silicate glass

NASA Astrophysics Data System (ADS)

Heaney, Alan Douglas

2000-08-01

The photosensitive nature of germano-silicate glass is widely used to create fiber-optic devices. This thesis examines the cause of photosensitivity in germano- silicate glass. The results of this research elucidate the role that germanium oxygen deficient defects play in the photosensitivity of hydrogen-loaded, germano-silicate glass. We find that defects are not vital to the photosensitivity of hydrogen-loaded, germano-silicate glass but they do enhance the effect. Quantitative measurements show that germanium oxygen deficient defects promote the formation of OH, GeH, and GeH2 when hydrogen-loaded, germano-silicate glass is exposed to ultraviolet light. A sol-gel process for fabricating germano-silicate glass in bulk samples has been developed. The sol-gel process produces high-quality, germano-silicate glass which can be tailored to contain defects or be relatively free of defects. Control over the glass defect concentration allows us to use sol-gel derived glass for comparative studies of the photosensitive process and for device applications. The unique properties of germano-silicate glass make it a likely choice for use in optical applications. To prove the feasibility of bulk devices, chirped-pulse amplification is demonstrated using gratings written in bulk germano-silicate glass.

Fatigue failure load of two resin-bonded zirconia-reinforced lithium silicate glass-ceramics: Effect of ceramic thickness.

PubMed

Monteiro, Jaiane Bandoli; Riquieri, Hilton; Prochnow, Catina; Guilardi, Luís Felipe; Pereira, Gabriel Kalil Rocha; Borges, Alexandre Luiz Souto; de Melo, Renata Marques; Valandro, Luiz Felipe

2018-06-01

To evaluate the effect of ceramic thickness on the fatigue failure load of two zirconia-reinforced lithium silicate (ZLS) glass-ceramics, adhesively cemented to a dentin analogue material. Disc-shaped specimens were allocated into 8 groups (n=25) considering two study factors: ZLS ceramic type (Vita Suprinity - VS; and Celtra Duo - CD), and ceramic thickness (1.0; 1.5; 2.0; and 2.5mm). A trilayer assembly (ϕ=10mm; thickness=3.5mm) was designed to mimic a bonded monolithic restoration. The ceramic discs were etched, silanized and luted (Variolink N) into a dentin analogue material. Fatigue failure load was determined using the Staircase method (100,000 cycles at 20Hz; initial fatigue load ∼60% of the mean monotonic load-to-failure; step size ∼5% of the initial fatigue load). A stainless-steel piston (ϕ=40mm) applied the load into the center of the specimens submerged in water. Fractographic analysis and Finite Element Analysis (FEA) were also performed. The ceramic thickness influenced the fatigue failure load for both ZLS materials: Suprinity (716N up to 1119N); Celtra (404N up to 1126N). FEA showed that decreasing ceramic thickness led to higher stress concentration on the cementing interface. Different ZLS glass-ceramic thicknesses influenced the fatigue failure load of the bonded system (i.e. the thicker the glass ceramic is, the higher the fatigue failure load will be). Different microstructures of the ZLS glass-ceramics might affect the fatigue behavior. FEA showed that the thicker the glass ceramic is, the lower the stress concentration at the tensile surface will be. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

Apatite and sodalite based glass-bonded waste forms for immobilization of 129I and mixed halide radioactive wastes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goel, Ashutosh; McCloy, John S.; Riley, Brian J.

The goal of the project was to utilize the knowledge accumulated by the team, in working with minerals for chloride wastes and biological apatites, toward the development of advanced waste forms for immobilizing 129I and mixed-halide wastes. Based on our knowledge, experience, and thorough literature review, we had selected two minerals with different crystal structures and potential for high chemical durability, sodalite and CaP/PbV-apatite, to form the basis of this project. The focus of the proposed effort was towards: (i) low temperature synthesis of proposed minerals (iodine containing sodalite and apatite) leading to the development of monolithic waste forms, (ii)more » development of a fundamental understanding of the atomic-scale to meso-scale mechanisms of radionuclide incorporation in them, and (iii) understanding of the mechanism of their chemical corrosion, alteration mechanism, and rates. The proposed work was divided into four broad sections. deliverables. 1. Synthesis of materials 2. Materials structural and thermal characterization 3. Design of glass compositions and synthesis glass-bonded minerals, and 4. Chemical durability testing of materials.« less

Aging of vitrified wastes: An experimental and analogical approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sterpenich, J.; Forestier, L. Le; Libourel, G.

1995-12-31

In order to tackle the problems of the longevity of vitrified wastes, the authors used two complementary approaches: an analogical approach to examine the leaching processes of vitreous matrices as a function of time and to evaluate the longevity of vitrified wastes, and an experimental approach based on leaching experiments which allowed the determination of the rate and the kinetics of release of each element under well known conditions. Despite the very different durations of alteration, around 1,000 years for the medieval stained glasses and several weeks for leaching experiments, the authors show that the results obtained in laboratory andmore » under natural conditions are comparable. Thus, studies of medieval stained glasses allow prediction of the alteration of vitreous matrices and in particular, of vitrified wastes, and can be used to determine the rates and kinetics of release of pollutants. Medieval stained glasses furnish an excellent model for understanding the aging of vitrified wastes over time periods of up to a thousand years.« less

Accelerated Leach Testing of GLASS: ALTGLASS Version 3.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trivelpiece, Cory L.; Jantzen, Carol M.; Crawford, Charles L.

The Accelerated Leach Testing of GLASS (ALTGLASS) database is a collection of data from short- and long-term product consistency tests (PCT, ASTM C1285 A and B) on high level waste (HLW) as well as low activity waste (LAW) glasses. The database provides both U.S. and international researchers with an archive of experimental data for the purpose of studying, modeling, or validating existing models of nuclear waste glass corrosion. The ALTGLASS database is maintained and updated by researchers at the Savannah River National Laboratory (SRNL). This newest version, ALTGLASS Version 3.0, has been updated with an additional 503 rows of datamore » representing PCT results from corrosion experiments conducted in the United States by the Savannah River National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and the Vitreous State Laboratory (SRNL, PNNL, ANL, VSL, respectively) as well as the National Nuclear Laboratory (NNL) in the United Kingdom.« less

Production of geopolymers using glass produced from DC plasma treatment of air pollution control (APC) residues.

PubMed

Kourti, Ioanna; Rani, D Amutha; Deegan, D; Boccaccini, A R; Cheeseman, C R

2010-04-15

Air pollution control (APC) residues are the hazardous waste produced from cleaning gaseous emissions at energy-from-waste (EfW) facilities processing municipal solid waste (MSW). APC residues have been blended with glass-forming additives and treated using DC plasma technology to produce a high calcium alumino-silicate glass. This research has investigated the optimisation and properties of geopolymers prepared from this glass. Work has shown that high strength geopolymers can be formed and that the NaOH concentration of the activating solution significantly affects the properties. The broad particle size distribution of the APC residue glass used in these experiments results in a microstructure that contains unreacted glass particles included within a geopolymer binder phase. The high calcium content of APC residues may cause the formation of some amorphous calcium silicate hydrate (C-S-H) gel. A mix prepared with S/L=3.4, Si/Al=2.6 and [NaOH]=6M in the activating solution, produced high strength geopolymers with compressive strengths of approximately 130 MPa. This material had high density (2070 kg/m(3)) and low porosity. The research demonstrates for the first time that glass derived from DC plasma treatment of APC residues can be used to form high strength geopolymer-glass composites that have potential for use in a range of applications. 2009 Elsevier B.V. All rights reserved.

Integrated Disposal Facility FY2011 Glass Testing Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Eric M.; Bacon, Diana H.; Kerisit, Sebastien N.

2011-09-29

Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to provide the technical basis for estimating radionuclide release from the engineered portion of the disposal facility (e.g., source term). Vitrifying the low-activity waste at Hanford is expected to generate over 1.6 x 10{sup 5} m{sup 3} of glass (Certa and Wells 2010). The volume of immobilized low-activity waste (ILAW) at Hanford is the largest in the DOE complex and is one of the largest inventories (approximately 8.9 x 10{sup 14} Bq total activity) of long-lived radionuclides, principally {sup 99}Tc (t{sub 1/2} = 2.1 x 10{sup 5}), plannedmore » for disposal in a low-level waste (LLW) facility. Before the ILAW can be disposed, DOE must conduct a performance assessment (PA) for the Integrated Disposal Facility (IDF) that describes the long-term impacts of the disposal facility on public health and environmental resources. As part of the ILAW glass testing program PNNL is implementing a strategy, consisting of experimentation and modeling, in order to provide the technical basis for estimating radionuclide release from the glass waste form in support of future IDF PAs. The purpose of this report is to summarize the progress made in fiscal year (FY) 2011 toward implementing the strategy with the goal of developing an understanding of the long-term corrosion behavior of low-activity waste glasses.« less

Recycling of waste automotive laminated glass and valorization of polyvinyl butyral through mechanochemical separation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swain, Basudev, E-mail: swain@iae.re.kr; Ryang Park, Jae; Yoon Shin, Dong

Due to strong binding, optical clarity, adhesion to many surfaces, toughness and flexibility polyvinyl butyral (PVB) resin films are commonly used in the automotive and architectural application as a protective interlayer in the laminated glass. Worldwide million tons of PVB waste generated from end-of-life automotive associated with various environmental issues. Stringent environmental directive, higher land cost eliminates land filling option, needs a study, we have developed a mechanochemical separation process to separate PVB resins from glass and characterized the separated PVB through various techniques, i.e., scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), infrared spectroscopy (IR) and nuclear magnetic resonancemore » spectroscopy (NMR). Commercial nonionic surfactants D201 used for the mechanochemical separation purpose. Through parameter optimization following conditions are considered to be the optimum condition; 30 vol% D201, stirring speed of 400 rpm, 35 °C temperature, operation time 1 h, and dilute D201 volume to waste automotive laminated glass weight ratio of ≈25. The technology developed in our laboratory is sustainable, environmentally friendly, techno-economical feasible process, capable of mass production (recycling). - Highlights: • Waste automotive laminated glass and polyvinyl butyral mechanochemically separated. • An economical total recovery and environment-friendly process has been developed. • It is a global problem rather than regional environmental issue has been addressed. • Without using hazardous chemical wastes are being converted to a wealth.« less

Comparative risk assessments for the production and interim storage of glass and ceramic waste forms: Defense waste processing facility

NASA Astrophysics Data System (ADS)

Huang, J. C.; Wright, W. V.

1982-04-01

The Defense Waste Processing Facility (DWPF) for immobilizing nuclear high level waste (HLW) is scheduled to be built. High level waste is produced when reactor components are subjected to chemical separation operations. Two candidates for immobilizing this HLW are borosilicate glass and crystalline ceramic, either being contained in weld sealed stainless steel canisters. A number of technical analyses are being conducted to support a selection between these two waste forms. The risks associated with the manufacture and interim storage of these two forms in the DWPF are compared. Process information used in the risk analysis was taken primarily from a DWPF processibility analysis. The DWPF environmental analysis provided much of the necessary environmental information.

Up-cycling waste glass to minimal water adsorption/absorption lightweight aggregate by rapid low temperature sintering: optimization by dual process-mixture response surface methodology.

PubMed

Velis, Costas A; Franco-Salinas, Claudia; O'Sullivan, Catherine; Najorka, Jens; Boccaccini, Aldo R; Cheeseman, Christopher R

2014-07-01

Mixed color waste glass extracted from municipal solid waste is either not recycled, in which case it is an environmental and financial liability, or it is used in relatively low value applications such as normal weight aggregate. Here, we report on converting it into a novel glass-ceramic lightweight aggregate (LWA), potentially suitable for high added value applications in structural concrete (upcycling). The artificial LWA particles were formed by rapidly sintering (<10 min) waste glass powder with clay mixes using sodium silicate as binder and borate salt as flux. Composition and processing were optimized using response surface methodology (RSM) modeling, and specifically (i) a combined process-mixture dual RSM, and (ii) multiobjective optimization functions. The optimization considered raw materials and energy costs. Mineralogical and physical transformations occur during sintering and a cellular vesicular glass-ceramic composite microstructure is formed, with strong correlations existing between bloating/shrinkage during sintering, density and water adsorption/absorption. The diametrical expansion could be effectively modeled via the RSM and controlled to meet a wide range of specifications; here we optimized for LWA structural concrete. The optimally designed LWA is sintered in comparatively low temperatures (825-835 °C), thus potentially saving costs and lowering emissions; it had exceptionally low water adsorption/absorption (6.1-7.2% w/wd; optimization target: 1.5-7.5% w/wd); while remaining substantially lightweight (density: 1.24-1.28 g.cm(-3); target: 0.9-1.3 g.cm(-3)). This is a considerable advancement for designing effective environmentally friendly lightweight concrete constructions, and boosting resource efficiency of waste glass flows.

GLASS VISCOSITY AS A FUNCTION OF TEMPERATURE AND COMPOSITION: A MODEL BASED ON ADAM-GIBBS EQUATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrma, Pavel R.

2008-07-01

Within the temperature range and composition region of processing and product forming, the viscosity of commercial and waste glasses spans over 12 orders of magnitude. This paper shows that a generalized Adam-Gibbs relationship reasonably approximates the real behavior of glasses with four temperature-independent parameters of which two are linear functions of the composition vector. The equation is subjected to two constraints, one requiring that the viscosity-temperature relationship approaches the Arrhenius function at high temperatures with a composition-independent pre-exponential factor and the other that the viscosity value is independent of composition at the glass-transition temperature. Several sets of constant coefficients weremore » obtained by fitting the generalized Adam-Gibbs equation to data of two glass families: float glass and Hanford waste glass. Other equations (the Vogel-Fulcher-Tammann equation, original and modified, the Avramov equation, and the Douglass-Doremus equation) were fitted to float glass data series and compared with the Adam-Gibbs equation, showing that Adam-Gibbs glass appears an excellent approximation of real glasses even as compared with other candidate constitutive relations.« less

Chemical composition measurements of the low activity waste (LAW) EPA-Series glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Edwards, T. B.

2016-03-01

In this report, the Savannah River National Laboratory provides chemical analysis results for a series of simulated low activity waste glasses provided by Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 100.2 to 100.8 wt %, indicating recovery of all components. Comparisons of the targetedmore » and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %.« less

Integrated Disposal Facility FY2010 Glass Testing Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Eric M.; Bacon, Diana H.; Kerisit, Sebastien N.

2010-09-30

Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to provide the technical basis for estimating radionuclide release from the engineered portion of the disposal facility (e.g., source term). Vitrifying the low-activity waste at Hanford is expected to generate over 1.6 × 105 m3 of glass (Puigh 1999). The volume of immobilized low-activity waste (ILAW) at Hanford is the largest in the DOE complex and is one of the largest inventories (approximately 0.89 × 1018 Bq total activity) of long-lived radionuclides, principally 99Tc (t1/2 = 2.1 × 105), planned for disposal in a low-level waste (LLW) facility.more » Before the ILAW can be disposed, DOE must conduct a performance assessement (PA) for the Integrated Disposal Facility (IDF) that describes the long-term impacts of the disposal facility on public health and environmental resources. As part of the ILAW glass testing program PNNL is implementing a strategy, consisting of experimentation and modeling, in order to provide the technical basis for estimating radionuclide release from the glass waste form in support of future IDF PAs. The purpose of this report is to summarize the progress made in fiscal year (FY) 2010 toward implementing the strategy with the goal of developing an understanding of the long-term corrosion behavior of low-activity waste glasses. The emphasis in FY2010 was the completing an evaluation of the most sensitive kinetic rate law parameters used to predict glass weathering, documented in Bacon and Pierce (2010), and transitioning from the use of the Subsurface Transport Over Reactive Multi-phases to Subsurface Transport Over Multiple Phases computer code for near-field calculations. The FY2010 activities also consisted of developing a Monte Carlo and Geochemical Modeling framework that links glass composition to alteration phase formation by 1) determining the structure of unreacted and reacted glasses for use as input information into Monte Carlo calculations, 2) compiling the solution data and alteration phases identified from accelerated weathering tests conducted with ILAW glass by PNNL and Viteous State Laboratory/Catholic University of America as well as other literature sources for use in geochemical modeling calculations, and 3) conducting several initial calculations on glasses that contain the four major components of ILAW-Al2O3, B2O3, Na2O, and SiO2.« less

Environmental performance of household waste management in Europe - An example of 7 countries.

PubMed

Andreasi Bassi, Susanna; Christensen, Thomas H; Damgaard, Anders

2017-11-01

An attributional life cycle assessment (LCA) of the management of 1ton of household waste was conducted in accordance with ISO 14044:2006 and the ILCD Handbook for seven European countries, namely Germany, Denmark, France, UK, Italy, Poland and Greece, representing different household waste compositions, waste management practices, technologies, and energy systems. National data were collected from a range of sources regarding household waste composition, household sorting efficiency, collection, waste treatments, recycling, electricity and heat composition, and technological efficiencies. The objective was to quantify the environmental performance in the different countries, in order to analyze the sources of the main environmental impacts and national differences which affect the results. In most of the seven countries, household waste management provides environmental benefits when considering the benefits of recycling of materials and recovering and utilization of energy. Environmental benefits come from paper recycling and, to a lesser extent, the recycling of metals and glass. Waste-to-energy plants can lead to an environmental load (as in France) or a saving (Germany and Denmark), depending mainly on the composition of the energy being substituted. Sensitivity analysis and a data quality assessment identified a range of critical parameters, suggesting from where better data should be obtained. The study concluded that household waste management is environmentally the best in European countries with a minimum reliance on landfilling, also induced by the implementation of the Waste Hierarchy, though environmental performance does not correlate clearly with the rate of material recycling. From an environmental point of view, this calls for a change in the waste management paradigm, with less focus on where the waste is routed and more of a focus on the quality and utilization of recovered materials and energy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vitrification of copper flotation waste.

PubMed

Karamanov, Alexander; Aloisi, Mirko; Pelino, Mario

2007-02-09

The vitrification of an hazardous iron-rich waste (W), arising from slag flotation of copper production, was studied. Two glasses, containing 30wt% W were melted for 30min at 1400 degrees C. The first batch, labeled WSZ, was obtained by mixing W, blast furnace slag (S) and zeolite tuff (Z), whereas the second, labeled WG, was prepared by mixing W, glass cullet (G), sand and limestone. The glass frits showed high chemical durability, measured by the TCLP test. The crystallization of the glasses was evaluated by DTA. The crystal phases formed were identified by XRD resulting to be pyroxene and wollastonite solid solutions, magnetite and hematite. The morphology of the glass-ceramics was observed by optical and scanning electron microscopy. WSZ composition showed a high rate of bulk crystallization and resulted to be suitable for producing glass-ceramics by a short crystallization heat-treatment. WG composition showed a low crystallization rate and good sinterability; glass-ceramics were obtained by sinter-crystallization of the glass frit.

World first in high level waste vitrification - A review of French vitrification industrial achievements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brueziere, J.; Chauvin, E.; Piroux, J.C.

2013-07-01

AREVA has more than 30 years experience in operating industrial HLW (High Level radioactive Waste) vitrification facilities (AVM - Marcoule Vitrification Facility, R7 and T7 facilities). This vitrification technology was based on borosilicate glasses and induction-heating. AVM was the world's first industrial HLW vitrification facility to operate in-line with a reprocessing plant. The glass formulation was adapted to commercial Light Water Reactor fission products solutions, including alkaline liquid waste concentrates as well as platinoid-rich clarification fines. The R7 and T7 facilities were designed on the basis of the industrial experience acquired in the AVM facility. The AVM vitrification process wasmore » implemented at a larger scale in order to operate the R7 and T7 facilities in-line with the UP2 and UP3 reprocessing plants. After more than 30 years of operation, outstanding record of operation has been established by the R7 and T7 facilities. The industrial startup of the CCIM (Cold Crucible Induction Melter) technology with enhanced glass formulation was possible thanks to the close cooperation between CEA and AREVA. CCIM is a water-cooled induction melter in which the glass frit and the waste are melted by direct high frequency induction. This technology allows the handling of highly corrosive solutions and high operating temperatures which permits new glass compositions and a higher glass production capacity. The CCIM technology has been implemented successfully at La Hague plant.« less

Proposed method for determining the thickness of glass in solar collector panels

NASA Technical Reports Server (NTRS)

Moore, D. M.

1980-01-01

An analytical method was developed for determining the minimum thickness for simply supported, rectangular glass plates subjected to uniform normal pressure environmental loads such as wind, earthquake, snow, and deadweight. The method consists of comparing an analytical prediction of the stress in the glass panel to a glass breakage stress determined from fracture mechanics considerations. Based on extensive analysis using the nonlinear finite element structural analysis program ARGUS, design curves for the structural analysis of simply supported rectangular plates were developed. These curves yield the center deflection, center stress and corner stress as a function of a dimensionless parameter describing the load intensity. A method of estimating the glass breakage stress as a function of a specified failure rate, degree of glass temper, design life, load duration time, and panel size is also presented.

Contact fatigue mechanisms as a function of crystal aspect ratio in baria-silicate glass ceramics

NASA Astrophysics Data System (ADS)

Suputtamongkol, Kallaya

2003-10-01

Ceramic materials are potentially useful for dental applications because of their esthetic potential and biocompatibility. However, the existence of fatigue damage in ceramics raises considerable concern regarding its effect on the life prediction of dental prostheses. During normal mastication, dental restorations are subjected to repeated loading more than a thousand times per day and relatively high clinical failure rates for ceramic prostheses have been reported. To simulate the intraoral loads, Hertzian indentation loading was used in this study to characterize the fatigue failure mechanisms of ceramic materials using clinically relevant parameters. The baria-silicate system was chosen because of the nearly identical composition between the crystal and the glass matrix. Little or no residual stress is expected from the elastic modulus and thermal expansion mismatches between the two phases. Crystallites with different aspect ratios can also be produced by controlled heat treatment schedules. The objective of this study was to characterize the effect of crystal morphology on the fatigue mechanisms of bariasilicate glass-ceramics under clinically relevant conditions. The results show that the failure of materials with a low toughness such as baria-silicate glass (0.7 MPa•m1/2) and glass-ceramic with an aspect ratio of 3/1 (1.3 MPa•m1/2) initiated from a cone crack developed during cyclic loading for 103 to 105 cycles. The mean strength values of baria-silicate glass and glass-ceramic with an aspect ratio of 3/1 decreased significantly as a result of the presence of a cone crack. Failure of baria-silicate glass-ceramics with an aspect ratio of 8/1 (Kc = 2.1 MPa•m1/2) was initiated from surface flaws caused by either polishing or cyclic loading. The gradual decrease of fracture stress was observed in specimens with an aspect ratio of 8/1 after loading in air for 103 to 10 5 cycles. A reduction of approximately 50% in fracture stress levels was found for specimens with an aspect ratio of 8/1 after loading for 10 5 cycles in deionized water. The mechanisms for cyclic fatigue crack propagation in baria-silicate glass-ceramics are similar to those observed under quasi-static loading conditions. An intergranular fracture path was observed in glass-ceramics with an aspect ratio of 3/1. For an aspect ratio of 8/1, a transgranular fracture mode was dominant.

Processing and characterization of unidirectional thermoplastic nanocomposites

NASA Astrophysics Data System (ADS)

Narasimhan, Kameshwaran

The manufacture of continuous fibre-reinforced thermoplastic nanocomposites is discussed for the case of E-Glass reinforced polypropylene (PP) matrix and for E-Glass reinforced Polyamide-6 (Nylon-6), with and without dispersed nanoclay (montmorillonite) platelets. The E-Glass/PP nanocomposite was manufactured using pultrusion, whereas the E-Glass/Nylon-6 nanocomposite was manufactured using compression molding. Mechanical characterization of nanocomposites were performed and compared with traditional microcomposites. Compressive as well as shear strength of nanocomposites was improved by improving the yield strength of the surrounding matrix through the dispersion of nanoclay. Significant improvements were achieved in compressive strength and shear strength with relatively low nanoclay loadings. Initially, polypropylene with and without nanoclay were melt intercalated using a single-screw extruder and the pultruded nanocomposite was fabricated using extruded pre-impregnated (pre-preg) tapes. Compression tests were performed as mandated by ASTM guidelines. SEM and TEM characterization revealed presence of nanoclay in an intercalated and partially exfoliated morphology. Mechanical tests confirmed significant improvements in compressive strength (˜122% at 10% nanoclay loading) and shear strength (˜60% at 3% nanoclay loading) in modified pultruded E-Glass/PP nanocomposites in comparison with baseline properties. Uniaxial tensile tests showed a small increase in tensile strength (˜3.4%) with 3% nanoclay loading. Subsequently, E-Glass/Nylon-6 nanocomposite panels were manufactured by compression molding. Compression tests were performed according to IITRI guidelines, whereas short beam shear and uni-axial tensile tests were performed according to ASTM standards. Mechanical tests confirmed strength enhancement with nanoclay addition, with a significant improvement in compressive strength (50% at 4% nanoclay loading) and shear strength (˜36% at 4% nanoclay loading) when compared with the baseline E-Glass/Nylon-6. Uni-axial tensile tests resulted in a small increase in tensile strength (˜3.2%) with 4% nanoclay loading. Also, hygrothermal aging (50°C and 100% RH) of baseline and nanoclay modified (4%) E-Glass/Nylon-6 was studied. It was observed that the moisture diffusion process followed Fickian diffusion. E-Glass/Nylon-6 modified with 4% nanoclay loading showed improved barrier performance with a significant reduction (˜30%) in moisture uptake compared to baseline E-Glass/Nylon-6 composites. Significant improvement in mechanical properties was also observed in hygrothermally aged nanocomposite specimens when compared with the aged baseline composite.

Engineering Glass Passivation Layers -Model Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skorski, Daniel C.; Ryan, Joseph V.; Strachan, Denis M.

2011-08-08

The immobilization of radioactive waste into glass waste forms is a baseline process of nuclear waste management not only in the United States, but worldwide. The rate of radionuclide release from these glasses is a critical measure of the quality of the waste form. Over long-term tests and using extrapolations of ancient analogues, it has been shown that well designed glasses exhibit a dissolution rate that quickly decreases to a slow residual rate for the lifetime of the glass. The mechanistic cause of this decreased corrosion rate is a subject of debate, with one of the major theories suggesting thatmore » the decrease is caused by the formation of corrosion products in such a manner as to present a diffusion barrier on the surface of the glass. Although there is much evidence of this type of mechanism, there has been no attempt to engineer the effect to maximize the passivating qualities of the corrosion products. This study represents the first attempt to engineer the creation of passivating phases on the surface of glasses. Our approach utilizes interactions between the dissolving glass and elements from the disposal environment to create impermeable capping layers. By drawing from other corrosion studies in areas where passivation layers have been successfully engineered to protect the bulk material, we present here a report on mineral phases that are likely have a morphological tendency to encrust the surface of the glass. Our modeling has focused on using the AFCI glass system in a carbonate, sulfate, and phosphate rich environment. We evaluate the minerals predicted to form to determine the likelihood of the formation of a protective layer on the surface of the glass. We have also modeled individual ions in solutions vs. pH and the addition of aluminum and silicon. These results allow us to understand the pH and ion concentration dependence of mineral formation. We have determined that iron minerals are likely to form a complete incrustation layer and we plan to look more closely at Vivianite [Fe3(PO4)2-8(H2O)] and Siderite [FeCO3] in the next stage of the project.« less

The long-term acceleration of waste glass corrosion: A preliminary review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kielpinski, A.L.

1995-07-01

Whereas a prior conception of glass dissolution assumed a relatively rapid initial dissolution which then slowed to a smaller, fairly constant longer-term rate, some recent work suggests that these two stages are followed by a third phase of dissolution, in which the dissolution rate is accelerated with respect to what had previously been thought of as the final long-term rate. The goals of the present study are to compile experimental data which may have a bearing on this phenomena, and to provide an initial assessment of these data. The Savannah River Technology Center (SRTC) is contracted to develop glass formulationmore » models for vitrification of Hanford low-level waste (LLW), in support of the Hanford Tank Waste Remediation System Technology Development Program. The phenomenon of an increase in corrosion rate, following a period characterized by a low corrosion rate, has been observed by a number of researchers on a number of waste glass compositions. Despite inherent ambiguities arising from SA/V (glass surface area to solution volume ratio) and other effects, valid comparisons can be made in which accelerated corrosion was observed in one test, but not in another. Some glass compositions do not appear to attain a plateau region; it may be that the observation of continued, non-negligible corrosion in these glasses represents a passage from the initial rate to the accelerated rate. The long-term corrosion is a function of the interaction between the glass and its environment, including the leaching solution and the surrounding materials. Reaction path modeling and stability field considerations have been used with some success to predict the changes in corrosion rate over time, due to these interactions. The accelerated corrosion phenomenon highlights the need for such integrated corrosion modeling and the scenario-specific nature of a particular glass composition`s durability.« less

Modelling aqueous corrosion of nuclear waste phosphate glass

NASA Astrophysics Data System (ADS)

Poluektov, Pavel P.; Schmidt, Olga V.; Kascheev, Vladimir A.; Ojovan, Michael I.

2017-02-01

A model is presented on nuclear sodium alumina phosphate (NAP) glass aqueous corrosion accounting for dissolution of radioactive glass and formation of corrosion products surface layer on the glass contacting ground water of a disposal environment. Modelling is used to process available experimental data demonstrating the generic inhibiting role of corrosion products on the NAP glass surface.

Municipal Solid Waste Management: Recycling, Resource Recovery, and Landfills. LC Science Tracer Bullet.

ERIC Educational Resources Information Center

Meikle, Teresa, Comp.

Municipal solid waste refers to waste materials generated by residential, commercial, and institutional sources, and consists predominantly of paper, glass, metals, plastics, and food and yard waste. Within the definition of the Solid Waste Disposal Act, municipal solid waste does not include sewage sludge or hazardous waste. The three main…

Glass breaking strength: The role of surface flaws and treatments

NASA Technical Reports Server (NTRS)

Moore, D.

1985-01-01

Although the intrinsic strength of silicon dioxide glass is of the order of 10 to the 6th power lb/sq in, the practical strength is roughly two orders of magnitude below this theoretical limit, and depends almost entirely on the surface condition of the glass, that is, the number and size of flaws and the residual surface compression (temper) in the glass. Glass parts always fail in tension when these flaws grow under sustained loading to some critical size. Research associated with glass encapsulated crystalline-Si photovoltaic (PV) modules has greatly expanded our knowledge of glass breaking strength and developed sizeable data base for commercially available glass types. A detailed design algorithm is developed for thickness sizing of rectangular glass plates subject to pressure loads. Additional studies examine the strength of glass under impact loading conditions such as that caused by hail. Although the fundamentals of glass breakage are directly applicable to thin film modules, the fracture strength of typical numerical glass must be replaced with data that reflect the high temperature tin oxide processing, laser scribing, and edge processing peculiar to thin film modules. The fundamentals of glass breakage applicable to thin film modules and preliminary fracture strength data for a variety of 1 ft square glass specimens representing preprocessed and post processed sheets from current amorphous-Si module manufacturers are presented.

Tellurite glasses for vitrification of technetium-99 from pyrochemical processing

NASA Astrophysics Data System (ADS)

Pyo, Jae-Young; Lee, Cheong Won; Park, Hwan-Seo; Yang, Jae Hwan; Um, Wooyong; Heo, Jong

2017-09-01

A new alkali-alumino tellurite glass composition was developed to immobilize highly-volatile technetium (Tc) wastes generated from the pyrochemical processing technology. Tellurite glass can incorporate up to 7 mass% of rhenium (Re, used as a surrogate for Tc) with an average retention of 86%. Normalized elemental releases evaluated by seven-day product consistency test (PCT) satisfied the immobilized low activity waste requirements of United States when concentration of Ca(ReO4)2 in the glass was <12 mass%. Re ions form Re7+ and are coordinated with four oxygens to form ReO4- tetrahedra. These tetrahedra bond to modifiers such as Ca2+ or Na+ that are further connected to the tellurite glass network by Ca2+ (or Na+) - non-bridging oxygen bonds.

Evaluation of final waste forms and recommendations for baseline alternatives to group and glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bleier, A.

1997-09-01

An assessment of final waste forms was made as part of the Federal Facilities Compliance Agreement/Development, Demonstration, Testing, and Evaluation (FFCA/DDT&E) Program because supplemental waste-form technologies are needed for the hazardous, radioactive, and mixed wastes of concern to the Department of Energy and the problematic wastes on the Oak Ridge Reservation. The principal objective was to identify a primary waste-form candidate as an alternative to grout (cement) and glass. The effort principally comprised a literature search, the goal of which was to establish a knowledge base regarding four areas: (1) the waste-form technologies based on grout and glass, (2) candidatemore » alternatives, (3) the wastes that need to be immobilized, and (4) the technical and regulatory constraints on the waste-from technologies. This report serves, in part, to meet this goal. Six families of materials emerged as relevant; inorganic, organic, vitrified, devitrified, ceramic, and metallic matrices. Multiple members of each family were assessed, emphasizing the materials-oriented factors and accounting for the fact that the two most prevalent types of wastes for the FFCA/DDT&E Program are aqueous liquids and inorganic sludges and solids. Presently, no individual matrix is sufficiently developed to permit its immediate implementation as a baseline alternative. Three thermoplastic materials, sulfur-polymer cement (inorganic), bitumen (organic), and polyethylene (organic), are the most technologically developed candidates. Each warrants further study, emphasizing the engineering and economic factors, but each also has limitations that regulate it to a status of short-term alternative. The crystallinity and flexible processing of sulfur provide sulfur-polymer cement with the highest potential for short-term success via encapsulation. Long-term immobilization demands chemical stabilization, which the thermoplastic matrices do not offer. Among the properties of the remaining candidates, those of glass-ceramics (devitrified matrices) represent the best compromise for meeting the probable stricter disposal requirements in the future.« less

The Load-Bearing Capacity of Timber-Glass Composite I-Beams Made with Polyurethane Adhesives

NASA Astrophysics Data System (ADS)

Rodacki, Konrad

2017-12-01

This article discusses the issue of composite timber-glass I-beams, which are an interesting alternative for load-bearing beams of ceilings and roofs. The reasoning behind the use of timber-glass I-beams is the combination of the best features of both materials - this enables the creation of particularly safe beams with regard to structural stability and post-breakage load capacity. Due to the significant differences between the bonding surfaces of timber and glass, a study on the adhesion of various adhesives to both surfaces is presented at the beginning of the paper. After examination, two adhesives were selected for offering the best performance when used with composite beams. The beams were investigated using a four-point bending test under quasi-static loading.

Mechanical characterization of glass fiber (woven roving/chopped strand mat E-glass fiber) reinforced polyester composites

NASA Astrophysics Data System (ADS)

Bhaskar, V. Vijaya; Srinivas, Kolla

2017-07-01

Polymer reinforced composites have been replacing most of the engineering material and their applications become more and more day by day. Polymer composites have been analyzing from past thirty five years for their betterment for adapting more applications. This paper aims at the mechanical properties of polyester reinforced with glass fiber composites. The glass fiber is reinforced with polyester in two forms viz Woven Rovings (WRG) and Chopped Strand Mat (CSMG) E-glass fibers. The composites are fabricated by hand lay-up technique and the composites are cut as per ASTM Standard sizes for corresponding tests like flexural, compression and impact tests, so that flexural strength, compression strength, impact strength and inter laminar shear stress(ILSS) of polymer matrix composites are analyzed. From the tests and further calculations, the polyester composites reinforced with Chopped Strand Mat glass fiber have shown better performance against flexural load, compression load and impact load than that of Woven Roving glass fiber.

Monitoring Damage Propagation in Glass Fiber Composites Using Carbon Nanofibers.

PubMed

Al-Sabagh, Ahmed; Taha, Eman; Kandil, Usama; Nasr, Gamal-Abdelnaser; Reda Taha, Mahmoud

2016-09-10

In this work, we report the potential use of novel carbon nanofibers (CNFs), dispersed during fabrication of glass fiber composites to monitor damage propagation under static loading. The use of CNFs enables a transformation of the typically non-conductive glass fiber composites into new fiber composites with appreciable electrical conductivity. The percolation limit of CNFs/epoxy nanocomposites was first quantified. The electromechanical responses of glass fiber composites fabricated using CNFs/epoxy nanocomposite were examined under static tension loads. The experimental observations showed a nonlinear change of electrical conductivity of glass fiber composites incorporating CNFs versus the stress level under static load. Microstructural investigations proved the ability of CNFs to alter the polymer matrix and to produce a new polymer nanocomposite with a connected nanofiber network with improved electrical properties and different mechanical properties compared with the neat epoxy. It is concluded that incorporating CNFs during fabrication of glass fiber composites can provide an innovative means of self-sensing that will allow damage propagation to be monitored in glass fiber composites.

Matt waste from glass separated collection: an eco-sustainable addition for new building materials.

PubMed

Bignozzi, M C; Saccani, A; Sandrolini, F

2009-01-01

Matt waste (MW), a by-product of purification processes of cullet derived from separated glass waste collection, has been studied as filler for self-compacting concrete and as an addition for newly blended cement. Properties of self-compacting concrete compared to reference samples are reported. They include characteristics at the fresh and hardened states, and the compressive strength and porosity of mortar samples that were formulated with increasing amounts of MW to be used as cement replacement (up to 50wt.%). The effects of matt waste are discussed with respect to the mechanical and microstructural characteristics of the resulting new materials.

Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.

The effectiveness of HLW vitrification is limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr)2O4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layer, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/or small-scale agglomerates, but, excessive agglomeration observed in high-Ni-Fe glass resulted in an under-prediction ofmore » accumulated layers, which gradually worsen over time as an increased number of agglomerates formed. Accumulation rate of ~53.8 ± 3.7 µm/h determined for this glass will result in ~26 mm thick layer in 20 days of melter idling.« less

Investigation of the stability of glass-ceramic composites containing CeTi 2 O 6 and CaZrTi 2 O 7 after ion implantation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paknahad, Elham; Grosvenor, Andrew P.

Glass-ceramic composite materials have been investigated for nuclear waste sequestration applications due to their ability to incorporate large amounts of radioactive waste elements. A key property that needs to be understood when developing nuclear waste sequestration materials is how the structure of the material responds to radioactive decay of nuclear waste elements, which can be simulated by high energy ion implantation. Borosilicate glass-ceramic composites containing brannerite-type (CeTi2O6) or zirconolite-type (CaZrTi2O7) oxides were synthesized at different annealing temperatures and investigated after being implanted with high-energy Au ions to mimic radiation induced structural damage. Backscattered electron (BSE) images were collected to investigatemore » the interaction of the brannerite crystallites with the glass matrix before and after implantation and showed that the morphology of the crystallites in the composite materials were not affected by radiation damage. Surface sensitive Ti K-edge glancing angle XANES spectra collected from the implanted composite materials showed that the structures of the CeTi2O6 and CaZrTi2O7 ceramics were damaged as a result of implantation; however, analysis of Si L2,3-edge XANES spectra indicated that the glass matrix was not affected by ion implantation.« less

Investigation of the stability of glass-ceramic composites containing CeTi2O6 and CaZrTi2O7 after ion implantation

NASA Astrophysics Data System (ADS)

Paknahad, Elham; Grosvenor, Andrew P.

2017-12-01

Glass-ceramic composite materials have been investigated for nuclear waste sequestration applications due to their ability to incorporate large amounts of radioactive waste elements. A key property that needs to be understood when developing nuclear waste sequestration materials is how the structure of the material responds to radioactive decay of nuclear waste elements, which can be simulated by high energy ion implantation. Borosilicate glass-ceramic composites containing brannerite-type (CeTi2O6) or zirconolite-type (CaZrTi2O7) oxides were synthesized at different annealing temperatures and investigated after being implanted with high-energy Au ions to mimic radiation induced structural damage. Backscattered electron (BSE) images were collected to investigate the interaction of the brannerite crystallites with the glass matrix before and after implantation and showed that the morphology of the crystallites in the composite materials were not affected by radiation damage. Surface sensitive Ti K-edge glancing angle XANES spectra collected from the implanted composite materials showed that the structures of the CeTi2O6 and CaZrTi2O7 ceramics were damaged as a result of implantation; however, analysis of Si L2,3-edge XANES spectra indicated that the glass matrix was not affected by ion implantation.

Effect of elasticity on stress distribution in CAD/CAM dental crowns: Glass ceramic vs. polymer-matrix composite.

PubMed

Duan, Yuanyuan; Griggs, Jason A

2015-06-01

Further investigations are required to evaluate the mechanical behaviour of newly developed polymer-matrix composite (PMC) blocks for computer-aided design/computer-aided manufacturing (CAD/CAM) applications. The purpose of this study was to investigate the effect of elasticity on the stress distribution in dental crowns made of glass-ceramic and PMC materials using finite element (FE) analysis. Elastic constants of two materials were determined by ultrasonic pulse velocity using an acoustic thickness gauge. Three-dimensional solid models of a full-coverage dental crown on a first mandibular molar were generated based on X-ray micro-CT scanning images. A variety of load case-material property combinations were simulated and conducted using FE analysis. The first principal stress distribution in the crown and luting agent was plotted and analyzed. The glass-ceramic crown had stress concentrations on the occlusal surface surrounding the area of loading and the cemented surface underneath the area of loading, while the PMC crown had only stress concentration on the occlusal surface. The PMC crown had lower maximum stress than the glass-ceramic crown in all load cases, but this difference was not substantial when the loading had a lateral component. Eccentric loading did not substantially increase the maximum stress in the prosthesis. Both materials are resistant to fracture with physiological occlusal load. The PMC crown had lower maximum stress than the glass-ceramic crown, but the effect of a lateral loading component was more pronounced for a PMC crown than for a glass-ceramic crown. Knowledge of the stress distribution in dental crowns with low modulus of elasticity will aid clinicians in planning treatments that include such restorations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermal properties of simulated Hanford waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodriguez, Carmen P.; Chun, Jaehun; Crum, Jarrod V.

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) will vitrify the mixed hazardous wastes generated from 45 years of plutonium production. The molten glasses will be poured into stainless steel containers or canisters and subsequently quenched for storage and disposal. Such highly energy-consuming processes require precise thermal properties of materials for appropriate facility design and operations. Key thermal properties (heat capacity, thermal diffusivity, and thermal conductivity) of representative high-level and low-activity waste glasses were studied as functions of temperature in the range of 200 to 800°C (relevant to the cooling process), implementing simultaneous differential scanning calorimetry-thermal gravimetry (DSC-TGA), Xe-flashmore » diffusivity, pycnometry, and dilatometry. The study showed that simultaneous DSC-TGA would be a reliable method to obtain heat capacity of various glasses at the temperature of interest. Accurate thermal properties from this study were shown to provide a more realistic guideline for capacity and time constraint of heat removal process, in comparison to the design basis conservative engineering estimates. The estimates, though useful for design in the absence measured physical properties, can now be supplanted and the measured thermal properties can be used in design verification activities.« less

Synthesizing optimal waste blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayan, V.; Diwekar, W.M.; Hoza, M.

Vitrification of tank wastes to form glass is a technique that will be used for the disposal of high-level waste at Hanford. Process and storage economics show that minimizing the total number of glass logs produced is the key to keeping cost as low as possible. The amount of glass produced can be reduced by blending of the wastes. The optimal way to combine the tanks to minimize the vole of glass can be determined from a discrete blend calculation. However, this problem results in a combinatorial explosion as the number of tanks increases. Moreover, the property constraints make thismore » problem highly nonconvex where many algorithms get trapped in local minima. In this paper the authors examine the use of different combinatorial optimization approaches to solve this problem. A two-stage approach using a combination of simulated annealing and nonlinear programming (NLP) is developed. The results of different methods such as the heuristics approach based on human knowledge and judgment, the mixed integer nonlinear programming (MINLP) approach with GAMS, and branch and bound with lower bound derived from the structure of the given blending problem are compared with this coupled simulated annealing and NLP approach.« less

Nucleation and crystal growth behavior of nepheline in simulated high-level waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K.; Amoroso, J.; Mcclane, D.

The Savannah River National Laboratory (SRNL) has been tasked with supporting glass formulation development and process control strategies in key technical areas, relevant to the Department of Energy’s Office of River Protection (DOE-ORP) and related to high-level waste (HLW) vitrification at the Waste Treatment and Immobilization Plant (WTP). Of specific interest is the development of predictive models for crystallization of nepheline (NaAlSiO4) in HLW glasses formulated at high alumina concentrations. This report summarizes recent progress by researchers at SRNL towards developing a predicative tool for quantifying nepheline crystallization in HLW glass canisters using laboratory experiments. In this work, differential scanningmore » calorimetry (DSC) was used to obtain the temperature regions over which nucleation and growth of nepheline occur in three simulated HLW glasses - two glasses representative of WTP projections and one glass representative of the Defense Waste Processing Facility (DWPF) product. The DWPF glass, which has been studied previously, was chosen as a reference composition and for comparison purposes. Complementary quantitative X-ray diffraction (XRD) and optical microscopy confirmed the validity of the methodology to determine nucleation and growth behavior as a function of temperature. The nepheline crystallization growth region was determined to generally extend from ~ 500 to >850 °C, with the maximum growth rates occurring between 600 and 700 °C. For select WTP glass compositions (high Al2O3 and B2O3), the nucleation range extended from ~ 450 to 600 °C, with the maximum nucleation rates occurring at ~ 530 °C. For the DWPF glass composition, the nucleation range extended from ~ 450 to 750 °C with the maximum nucleation rate occurring at ~ 640 °C. The nepheline growth at the peak temperature, as determined by XRD, was between 35 - 75 wt.% /hour. A maximum nepheline growth rate of ~ 0.1 mm/hour at 700 °C was measured for the DWPF composition using optical microscopy. This research establishes a viable alternative to more traditional techniques for evaluating nepheline crystallization in large numbers of glasses, which are prohibitively time consuming or otherwise impractical. The ultimate objective is to combine the nucleation and growth information obtained from DSC, like that presented in this report, with computer simulations of glass cooling within the canister to accurately predict nepheline crystallization in HLW during processing through WTP.« less

Accelerated Weathering of Waste Glass at 90°C with the Pressurized Unsaturated Flow (PUF) Apparatus: Implications for Predicting Glass Corrosion with a Reactive Transport Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Eric M.; Bacon, Diana H.

2009-09-21

The interest in the long-term durability of waste glass stems from the need to predict radionuclide release rates from the corroding glass over geologic time-scales. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test-B, and pressurized unsaturated flow (PUF)]. Currently, the PUF test is the only method that can mimic the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitor the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior.more » One dimensional reactive chemical transport simulations of glass dissolution and secondary phase formation during a 1.5-year long PUF experiment was conducted with the subsurface transport over reactive multi-phases (STORM) code. Results show that parameterization of the computer model by combining direct laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over geologic-time scales.« less

Estimation of marginal costs at existing waste treatment facilities.

PubMed

Martinez-Sanchez, Veronica; Hulgaard, Tore; Hindsgaul, Claus; Riber, Christian; Kamuk, Bettina; Astrup, Thomas F

2016-04-01

This investigation aims at providing an improved basis for assessing economic consequences of alternative Solid Waste Management (SWM) strategies for existing waste facilities. A bottom-up methodology was developed to determine marginal costs in existing facilities due to changes in the SWM system, based on the determination of average costs in such waste facilities as function of key facility and waste compositional parameters. The applicability of the method was demonstrated through a case study including two existing Waste-to-Energy (WtE) facilities, one with co-generation of heat and power (CHP) and another with only power generation (Power), affected by diversion strategies of five waste fractions (fibres, plastic, metals, organics and glass), named "target fractions". The study assumed three possible responses to waste diversion in the WtE facilities: (i) biomass was added to maintain a constant thermal load, (ii) Refused-Derived-Fuel (RDF) was included to maintain a constant thermal load, or (iii) no reaction occurred resulting in a reduced waste throughput without full utilization of the facility capacity. Results demonstrated that marginal costs of diversion from WtE were up to eleven times larger than average costs and dependent on the response in the WtE plant. Marginal cost of diversion were between 39 and 287 € Mg(-1) target fraction when biomass was added in a CHP (from 34 to 303 € Mg(-1) target fraction in the only Power case), between -2 and 300 € Mg(-1) target fraction when RDF was added in a CHP (from -2 to 294 € Mg(-1) target fraction in the only Power case) and between 40 and 303 € Mg(-1) target fraction when no reaction happened in a CHP (from 35 to 296 € Mg(-1) target fraction in the only Power case). Although average costs at WtE facilities were highly influenced by energy selling prices, marginal costs were not (provided a response was initiated at the WtE to keep constant the utilized thermal capacity). Failing to systematically address and include costs in existing waste facilities in decision-making may unintendedly lead to higher overall costs at societal level. To avoid misleading conclusions, economic assessment of alternative SWM solutions should not only consider potential costs associated with alternative treatment but also include marginal costs associated with existing facilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Process for treating alkaline wastes for vitrification

DOEpatents

Hsu, Chia-lin W.

1995-01-01

A process for treating alkaline wastes for vitrification. The process involves acidifying the wastes with an oxidizing agent such as nitric acid, then adding formic acid as a reducing agent, and then mixing with glass formers to produce a melter feed. The nitric acid contributes nitrates that act as an oxidant to balance the redox of the melter feed, prevent reduction of certain species to produce conducting metals, and lower the pH of the wastes to a suitable level for melter operation. The formic acid reduces mercury compounds to elemental mercury for removal by steam stripping, and MnO.sub.2 to the Mn(II) ion to prevent foaming of the glass melt. The optimum amounts of nitric acid and formic acid are determined in relation to the composition of the wastes, including the concentrations of mercury (II) and MnO.sub.2, noble metal compounds, nitrates, formates and so forth. The process minimizes the amount of hydrogen generated during treatment, while producing a redox-balanced feed for effective melter operation and a quality glass product.

Process for treating alkaline wastes for vitrification

DOEpatents

Hsu, C.L.W.

1995-07-25

A process is described for treating alkaline wastes for vitrification. The process involves acidifying the wastes with an oxidizing agent such as nitric acid, then adding formic acid as a reducing agent, and then mixing with glass formers to produce a melter feed. The nitric acid contributes nitrates that act as an oxidant to balance the redox of the melter feed, prevent reduction of certain species to produce conducting metals, and lower the pH of the wastes to a suitable level for melter operation. The formic acid reduces mercury compounds to elemental mercury for removal by steam stripping, and MnO{sub 2} to the Mn(II) ion to prevent foaming of the glass melt. The optimum amounts of nitric acid and formic acid are determined in relation to the composition of the wastes, including the concentrations of mercury (II) and MnO{sub 2}, noble metal compounds, nitrates, formates and so forth. The process minimizes the amount of hydrogen generated during treatment, while producing a redox-balanced feed for effective melter operation and a quality glass product. 4 figs.

Structure of rhenium-containing sodium borosilicate glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goel, Ashutosh; McCloy, John S.; Windisch, Charles F.

2013-03-01

A series of sodium borosilicate glasses were synthesized with increasing fractions of KReO4 or Re2O7, to 10000 ppm (1 mass%) target Re in glass, to assess the effects of large concentrations of rhenium on glass structure and to estimate the solubility of technetium, a radioactive component in typical low active waste nuclear waste glasses. Magic angle spinning nuclear magnetic resonance (MAS-NMR), Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy were performed to characterize the glasses as a function of Re source additions. In general, silicon was found coordinated in a mixture of Q2 and Q3 structural units, while Al wasmore » 4-coordinated and B was largely 3-coordinate and partially 4-coordinated. The rhenium source did not appear to have significant effects on the glass structure. Thus, at the up to the concentrations that remain in dissolved in glass, ~3000 ppm Re by mass maximum. , the Re appeared to be neither a glass-former nor a strong glass modifier., Rhenium likely exists in isolated ReO4- anions in the interstices of the glass network, as evidenced by the polarized Raman spectrum of the Re glass in the absence of sulfate. Analogous to SO42-¬ in similar glasses, ReO4- is likely a network modifier and forms alkali salt phases on the surface and in the bulk glass above solubility.« less

EFFECTS OF QUARTZ PARTICLE SIZE AND SUCROSE ADDITION ON MELTING BEHAVIOR OF A MELTER FEED FOR HIGH-LEVEL GLASS

DOE Office of Scientific and Technical Information (OSTI.GOV)

MARCIAL J; KRUGER AA; HRMA PR

2010-07-28

The behavior of melter feed (a mixture of nuclear waste and glass-forming additives) during waste-glass processing has a significant impact on the rate of the vitrification process. We studied the effects of silica particle size and sucrose addition on the volumetric expansion (foaming) of a high-alumina feed and the rate of dissolution of silica particles in feed samples heated at 5 C/min up to 1200 C. The initial size of quartz particles in feed ranged from 5 to 195 {micro}m. The fraction of the sucrose added ranged from 0 to 0.20 g per g glass. Extensive foaming occurred only inmore » feeds with 5-{micro}m quartz particles; particles {ge}150 {micro}m formed clusters. Particles of 5 {micro}m completely dissolved by 900 C whereas particles {ge}150 {micro}m did not fully dissolve even when the temperature reached 1200 C. Sucrose addition had virtually zero impact on both foaming and the dissolution of silica particles. Over 100 sites in the United States are currently tasked with the storage of nuclear waste. The largest is the Hanford Site located in southeastern Washington State with 177 subterranean tanks containing over fifty-million gallons of nuclear waste from plutonium production from 1944 through 1987. This waste will be vitrified at the Hanford Tank Waste Treatment and Immobilization Plant. In the vitrification process, feed is charged into a melter and converted into glass to be ultimately stored in a permanent repository. The duration of waste-site cleanups by the vitrification process depends on the rate of melting, i.e., on the rate of the feed-to-glass conversion. Foaming associated with the melting process and the rate of dissolution of quartz particles (silica being the major glass-forming additive) are assumed to be important factors that influence the rate of melting. Previous studies on foaming of high-alumina feed demonstrated that varying the makeup of a melter feed has a significant impact on foaming. The volume of feeds that contained 5-{micro}m quartz particles substantially increased because of foaming. The extent of foaming decreased as the particle size of quartz increased. Moreover, samples containing quartz particles 195 {micro}m formed agglomerates at temperatures above 900 C that only slowly dissolved in the melt. This study continues previous work on the feed-melting process, specifically on the effects of the size of silica particles on the formation of nuclear-waste glasses to determine a suitable range of silica particle sizes that causes neither excessive foaming nor undesirable agglomeration. Apart from varying the silica-particle size, carbon was added in the form of sucrose. Sucrose has been used to accelerate the rate of melting. In this study, we have observed its impact on feed foaming and quartz dissolution.« less

40 CFR 62.14590 - What should I include in my waste management plan?

Code of Federal Regulations, 2010 CFR

2010-07-01

... in my waste management plan? A waste management plan must include consideration of the reduction or separation of waste-stream elements such as paper, cardboard, plastics, glass, batteries, or metals; or the... waste management measures already in place, the costs of additional measures, the emissions reductions...

The combined effect of glass buffer strips and stitching on the damage tolerance of composites

NASA Technical Reports Server (NTRS)

Kullerd, Susan M.

1993-01-01

Recent research has demonstrated that through-the-thickness stitching provides major improvements in the damage tolerance of composite laminates loaded in compression. However, the brittle nature of polymer matrix composites makes them susceptible to damage propagation, requiring special material applications and designs to limit damage growth. Glass buffer strips, embedded within laminates, have shown the potential for improving the damage tolerance of unstitched composite laminates loaded in tension. The glass buffer strips, less stiff than the surrounding carbon fibers, arrest crack growth in composites under tensile loads. The present study investigates the damage tolerance characteristics of laminates that contain both stitching and glass buffer strips.

Combined Experimental and Computational Approach to Predict the Glass-Water Reaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Eric M.; Bacon, Diana H.

2011-10-01

The use of mineral and glass dissolution rates measured in laboratory experiments to predict the weathering of primary minerals and volcanic and nuclear waste glasses in field studies requires the construction of rate models that accurately describe the weathering process over geologic timescales. Additionally, the need to model the long-term behavior of nuclear waste glass for the purpose of estimating radionuclide release rates requires that rate models be validated with long-term experiments. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test B, and pressurized unsaturated flow (PUF)], thereby reducingmore » the duration required to evaluate long-term performance. Currently, the PUF test is the only method that mimics the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitors the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. A one-dimensional reactive chemical transport simulation of glass dissolution and secondary phase formation during a 1.5-year-long PUF experiment was conducted with the Subsurface Transport Over Reactive Multiphases (STORM) code. Results show that parameterization of the computer model by combining direct bench scale laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over the length of the experiment. Over the 1.5-year-long test duration, the rate decreased from 0.2 to 0.01 g/(m2 day) based on B release for low-activity waste glass LAWA44. The observed decrease is approximately two orders of magnitude higher than the decrease observed under static conditions with the SON68 glass (estimated to be a decrease by four orders of magnitude) and suggests that the gel-layer properties are less protective under these dynamic conditions.« less

Wastes as Aggregates, Binders or Additions in Mortars: Selecting Their Role Based on Characterization.

PubMed

Farinha, Catarina Brazão; de Brito, Jorge; Veiga, Rosário; Fernández, J M; Jiménez, J R; Esquinas, A R

2018-03-20

The production of waste has increased over the years and, lacking a recycle or recovery solution, it is forwarded to landfill. The incorporation of wastes in cement-based materials is a solution to reduce waste deposition. In this regard, some researchers have been studying the incorporation of wastes with different functions: aggregate, binder and addition. The incorporation of wastes should take advantage of their characteristics. It requires a judicious analysis of their particles. This research involves the analysis of seven industrial wastes: biomass ashes, glass fibre, reinforced polymer dust, sanitary ware, fluid catalytic cracking, acrylic fibre, textile fibre and glass fibre. The main characteristics and advantages of each waste are enunciated and the best type of introduction in mortars is discussed. The characterization of the wastes as particles is necessary to identify the most suitable incorporation in mortars. In this research, some wastes are studied with a view to their re-use or recycling in mortars. Thus, this research focuses on the chemical, physical and mechanical characterization of industrial wastes and identification of the potentially most advantageous type of incorporation.

Wastes as Aggregates, Binders or Additions in Mortars: Selecting Their Role Based on Characterization

PubMed Central

de Brito, Jorge; Veiga, Rosário

2018-01-01

The production of waste has increased over the years and, lacking a recycle or recovery solution, it is forwarded to landfill. The incorporation of wastes in cement-based materials is a solution to reduce waste deposition. In this regard, some researchers have been studying the incorporation of wastes with different functions: aggregate, binder and addition. The incorporation of wastes should take advantage of their characteristics. It requires a judicious analysis of their particles. This research involves the analysis of seven industrial wastes: biomass ashes, glass fibre, reinforced polymer dust, sanitary ware, fluid catalytic cracking, acrylic fibre, textile fibre and glass fibre. The main characteristics and advantages of each waste are enunciated and the best type of introduction in mortars is discussed. The characterization of the wastes as particles is necessary to identify the most suitable incorporation in mortars. In this research, some wastes are studied with a view to their re-use or recycling in mortars. Thus, this research focuses on the chemical, physical and mechanical characterization of industrial wastes and identification of the potentially most advantageous type of incorporation. PMID:29558418

SLURRY MIX EVAPORATOR BATCH ACCEPTABILITY AND TEST CASES OF THE PRODUCT COMPOSITION CONTROL SYSTEM WITH THORIUM AS A REPORTABLE ELEMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, T.

2010-10-07

The Defense Waste Processing Facility (DWPF), which is operated by Savannah River Remediation, LLC (SRR), has recently begun processing Sludge Batch 6 (SB6) by combining it with Frit 418 at a nominal waste loading (WL) of 36%. A unique feature of the SB6/Frit 418 glass system, as compared to the previous glass systems processed in DWPF, is that thorium will be a reportable element (i.e., concentrations of elemental thorium in the final glass product greater than 0.5 weight percent (wt%)) for the resulting wasteform. Several activities were initiated based upon this unique aspect of SB6. One of these was anmore » investigation into the impact of thorium on the models utilized in DWPF's Product Composition and Control System (PCCS). While the PCCS is described in more detail below, for now note that it is utilized by Waste Solidification Engineering (WSE) to evaluate the acceptability of each batch of material in the Slurry Mix Evaporator (SME) before this material is passed on to the melter. The evaluation employs models that predict properties associated with processability and product quality from the composition of vitrified samples of the SME material. The investigation of the impact of thorium on these models was conducted by Peeler and Edwards [1] and led to a recommendation that DWPF can process the SB6/Frit 418 glass system with ThO{sub 2} concentrations up to 1.8 wt% in glass. Questions also arose regarding the handling of thorium in the SME batch acceptability process as documented by Brown, Postles, and Edwards [2]. Specifically, that document is the technical bases of PCCS, and while Peeler and Edwards confirmed the reliability of the models, there is a need to confirm that the current implementation of DWPF's PCCS appropriately handles thorium as a reportable element. Realization of this need led to a Technical Task Request (TTR) prepared by Bricker [3] that identified some specific SME-related activities that the Savannah River National Laboratory (SRNL) was requested to conduct. SRNL issued a Task Technical and Quality Assurance (TT&QA) plan [4] in response to the SRR request. The conclusions provided in this report are that no changes need to be made to the SME acceptability process (i.e., no modifications to WSRC-TR-95-00364, Revision 5, are needed) and no changes need to be made to the Product Composition Control System (PCCS) itself (i.e. the spreadsheet utilized by Waste Solidification Engineering (WSE) for acceptability decisions does not require modification) in response to thorium becoming a reportable element for DWPF operations. In addition, the inputs and results for the two test cases requested by WSE for use in confirming the successful activation of thorium as a reportable element for DWPF operations during the processing of SB6 are presented in this report.« less

Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol M.; Trivelpiece, Cory L.; Crawford, Charles L.

Glass corrosion data from the ALTGLASS™ database were used to determine if gel compositions, which evolve as glass systems corrode, are correlated with the generation of zeolites and subsequent increase in the glass dissolution rate at long times. The gel compositions were estimated based on the difference between the elemental glass starting compositions and the measured elemental leachate concentrations from the long-term product consistency tests (ASTM C1285) at various stages of dissolution, ie, reaction progress. A well-characterized subset of high level waste glasses from the database was selected: these glasses had been leached for 15-20 years at reaction progresses upmore » to ~80%. The gel composition data, at various reaction progresses, were subjected to a step-wise regression, which demonstrated that hydrogel compositions with Si*/Al* ratios of <1.0 did not generate zeolites and maintained low dissolution rates for the duration of the experiments. Glasses that formed hydrogel compositions with Si^*/Al^* ratios ≥1, generated zeolites accompanied by a resumption in the glass dissolution rate. Finally, the role of the gel Si/Al ratio, and the interactions with the leachate, provides the fundamental understanding needed to predict if and when the glass dissolution rate will increase due to zeolitization.« less

Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging

DOE PAGES

Jantzen, Carol M.; Trivelpiece, Cory L.; Crawford, Charles L.; ...

2017-02-18

Glass corrosion data from the ALTGLASS™ database were used to determine if gel compositions, which evolve as glass systems corrode, are correlated with the generation of zeolites and subsequent increase in the glass dissolution rate at long times. The gel compositions were estimated based on the difference between the elemental glass starting compositions and the measured elemental leachate concentrations from the long-term product consistency tests (ASTM C1285) at various stages of dissolution, ie, reaction progress. A well-characterized subset of high level waste glasses from the database was selected: these glasses had been leached for 15-20 years at reaction progresses upmore » to ~80%. The gel composition data, at various reaction progresses, were subjected to a step-wise regression, which demonstrated that hydrogel compositions with Si*/Al* ratios of <1.0 did not generate zeolites and maintained low dissolution rates for the duration of the experiments. Glasses that formed hydrogel compositions with Si^*/Al^* ratios ≥1, generated zeolites accompanied by a resumption in the glass dissolution rate. Finally, the role of the gel Si/Al ratio, and the interactions with the leachate, provides the fundamental understanding needed to predict if and when the glass dissolution rate will increase due to zeolitization.« less

Green remediation and recycling of contaminated sediment by waste-incorporated stabilization/solidification.

PubMed

Wang, Lei; Tsang, Daniel C W; Poon, Chi-Sun

2015-03-01

Navigational/environmental dredging of contaminated sediment conventionally requires contained marine disposal and continuous monitoring. This study proposed a green remediation approach to treat and recycle the contaminated sediment by means of stabilization/solidification enhanced by the addition of selected solid wastes. With an increasing amount of contaminated sediment (20-70%), the 28-d compressive strength of sediment blocks decreased from greater than 10MPa to slightly above 1MPa. For augmenting the cement hydration, coal fly ash was more effective than lime and ground seashells, especially at low sediment content. The microscopic and spectroscopic analyses showed varying amounts of hydration products (primarily calcium hydroxide and calcium silicate hydrate) in the presence of coal fly ash, signifying the influence of pozzolanic reaction. To facilitate the waste utilization, cullet from beverage glass bottles and bottom ashes from coal combustion and waste incineration were found suitable to substitute coarse aggregate at 33% replacement ratio, beyond which the compressive strength decreased accordingly. The mercury intrusion porosimetry analysis indicated that the increase in the total pore area and average pore diameter were linearly correlated with the decrease of compressive strength due to waste replacement. All the sediment blocks complied with the acceptance criteria for reuse in terms of metal leachability. These results suggest that, with an appropriate mixture design, contaminated sediment and waste materials are useful resources for producing non-load-bearing masonry units or fill materials for construction uses. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of phosphate glass recrystallization on the stability of a waste matrix to leaching

NASA Astrophysics Data System (ADS)

Yudintsev, S. V.; Pervukhina, A. M.; Mokhov, A. V.; Malkovsky, V. I.; Stefanovsky, S. V.

2017-04-01

In Russia, highly radioactive liquid wastes from recycling of spent fuel of nuclear reactors are solidified into Na-Al-P glass for underground storage. The properties of the matrix including the radionuclide fixation will change with time due to crystallization. This is supported by the results of study of the interaction between glassy matrices, products of their crystallization, and water. The concentration of Cs in a solution at the contact of a recrystallized sample increased by three orders of magnitude in comparison with an experiment with glass. This difference is nearly one order of magnitude for Sr, Ce, and Nd (simulators of actinides) and U due to their incorporation into phases with low solubility in water. Based on data on the compositional change of solutions after passing through filters of various diameters, it is concluded that Cs occurs in the dissolved state in runs with a glass and recrystallized matrix. At the same time, Sr, lanthanides, and U occur in the dissolved state and in the composition of colloids in runs with glass, and mostly in colloid particles after contact with the recrystallized sample. These results should be regarded for substantiation of safety for geological waste storage.

Effect of clayey groundwater on the dissolution rate of SON68 simulated nuclear waste glass at 70 °C

NASA Astrophysics Data System (ADS)

De Echave, T.; Tribet, M.; Jollivet, P.; Marques, C.; Gin, S.; Jégou, C.

2018-05-01

To predict the long-term behavior of high-level radioactive waste glass, it is necessary to study aqueous dissolution of the glass matrix under geological repository conditions. The present article focuses on SON68 (an inactive surrogate of the R7T7 glass) glass alteration in synthetic clayey groundwater at 70 °C. Experiments in deionized water as reference were also performed in the same conditions. Results are in agreement with those of previous studies showing that magnesium present in the solution is responsible for higher glass alteration. This effect is transient and pH-dependent: Once all the magnesium is consumed, the glass alteration rate diminishes. Precipitation of magnesium silicate of the smectite group seems to be the main factor for the increased glass alteration. A pH threshold of 7.5-7.8 was found, above which precipitation of these magnesium silicates at 70 °C is possible. TEM observations reveal that magnesium silicates grow at the expense of the passivating gel, which partly dissolves, forming large pores which increase mass transfer between the reacting glass surface and the bulk solution.

Fabrication and characterization of bioactive glass-ceramic using soda-lime-silica waste glass.

PubMed

Abbasi, Mojtaba; Hashemi, Babak

2014-04-01

Soda-lime-silica waste glass was used to synthesize a bioactive glass-ceramic through solid-state reactions. In comparison with the conventional route, that is, the melt-quenching and subsequent heat treatment, the present work is an economical technique. Structural and thermal properties of the samples were examined by X-ray diffraction (XRD) and differential thermal analysis (DTA). The in vitro test was utilized to assess the bioactivity level of the samples by Hanks' solution as simulated body fluid (SBF). Bioactivity assessment by atomic absorption spectroscopy (AAS) and scanning electron microscopy (SEM) was revealed that the samples with smaller amount of crystalline phase had a higher level of bioactivity. Copyright © 2014 Elsevier B.V. All rights reserved.

Plasma treatment of air pollution control residues.

PubMed

Amutha Rani, D; Gomez, E; Boccaccini, A R; Hao, L; Deegan, D; Cheeseman, C R

2008-01-01

Air pollution control (APC) residues from waste incineration have been blended with silica and alumina and the mix melted using DC plasma arc technology. The chemical composition of the fully amorphous homogeneous glass formed has been determined. Waste acceptance criteria compliance leach testing demonstrates that the APC residue derived glass releases only trace levels of heavy metals (Pb (<0.007mg/kg) and Zn (0.02mg/kg)) and Cl(-) (0.2mg/kg). These are significantly below the limit values for disposal to inert landfill. It is concluded that plasma treatment of APC residues can produce an inert glass that may have potential to be used either in bulk civil engineering applications or in the production of higher value glass-ceramic products.

Anti-scratch AlMgB14 Gorilla® Glass coating

NASA Astrophysics Data System (ADS)

Putrolaynen, V. V.; Grishin, A. M.; Rigoev, I. V.

2017-10-01

Hard aluminum-magnesium boride (BAM) films were fabricated onto Corning® Gorilla® Glass by radio-frequency magnetron sputtering of a single stoichiometric AlMgB14 target. BAM films exhibit a Vickers hardness from 10 to 30 GPa and a Young's modulus from 80 to 160 GPa depending on applied loading forces. Deposited hard coating increases the critical load at which glass substrate cracks. The adhesion energy of BAM films on Gorilla® Glass is 6.4 J/m2.

A Strategy for Maintenance of the Long-Term Performance Assessment of Immobilized Low-Activity Waste Glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryan, Joseph V.; Freedman, Vicky L.

2016-09-28

Approximately 50 million gallons of high-level radioactive mixed waste has accumulated in 177 buried single- and double-shell tanks at the Hanford Site in southeastern Washington State as a result of the past production of nuclear materials, primarily for defense uses. The United States Department of Energy (DOE) is proceeding with plans to permanently dispose of this waste. Plans call for separating the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, which will be vitrified at the Hanford Waste Treatment and Immobilization Plant (WTP). Principal radionuclides of concern in LAW are 99Tc, 129I, and U, while non-radioactive contaminantsmore » of concern are Cr and nitrate/nitrite. HLW glass will be sent off-site to an undetermined federal site for deep geological disposal while the much larger volume of immobilized low-activity waste will be placed in the on-site, near-surface Integrated Disposal Facility (IDF).« less

Low-temperature lithium diffusion in simulated high-level boroaluminosilicate nuclear waste glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neeway, James J.; Kerisit, Sebastien N.; Gin, Stephane

2014-12-01

Ion exchange is recognized as an integral, if underrepresented, mechanism influencing glass corrosion. However, due to the formation of various alteration layers in the presence of water, it is difficult to conclusively deconvolute the mechanisms of ion exchange from other processes occurring simultaneously during corrosion. In this work, an operationally inert non-aqueous solution was used as an alkali source material to isolate ion exchange and study the solid-state diffusion of lithium. Specifically, the experiments involved contacting glass coupons relevant to the immobilization of high-level nuclear waste, SON68 and CJ-6, which contained Li in natural isotope abundance, with a non-aqueous solutionmore » of 6LiCl dissolved in dimethyl sulfoxide at 90 °C for various time periods. The depth profiles of major elements in the glass coupons were measured using time-of-flight secondary ion mass spectrometry (ToF-SIMS). Lithium interdiffusion coefficients, D Li, were then calculated based on the measured depth profiles. The results indicate that the penetration of 6Li is rapid in both glasses with the simplified CJ-6 glass (D 6Li ≈ 4.0-8.0 × 10 -21 m 2/s) exhibiting faster exchange than the more complex SON68 glass (D Li ≈ 2.0-4.0 × 10 -21 m 2/s). Additionally, sodium ions present in the glass were observed to participate in ion exchange reactions; however, different diffusion coefficients were necessary to fit the diffusion profiles of the two alkali ions. Implications of the diffusion coefficients obtained in the absence of alteration layers to the long-term performance of nuclear waste glasses in a geological repository system are also discussed.« less

Thermal and physicochemical properties important for the long term behavior of nuclear waste glasses

NASA Astrophysics Data System (ADS)

Matzke, Hj.; Vernaz, E.

High level nuclear waste from reprocessing of spent nuclear fuel has to be solidified in a stable matrix for safe long-time storage. Vitrification in borosilicate glasses is the technique accepted worldwide as the best combination of engineering constraints from fabrication and physicochemical properties of the matrix. A number of different glasses was developed in different national programs. The criteria and the reasons for selecting the final compositions are described briefly. Emphasis is placed on the French product R7T7 and on thermal and physicochemical properties though glasses developed in other national projects (e.g., the German product GP 98/12, etc.) are also treated. The basic physical and mechanical properties and the chemical durability of the glass in contact with water are described. The basic mechanisms of aqueous corrosion are discussed and the evolving modelling of the leaching process is dealt with, as well as effects of container material, backfill, etc. The thermal behavior has also been studied and extensive data exist on diffusion of glass constituents (Na) and of interesting elements of the waste such as the alkalis Rb and Cs or the actinides U and Pu, as well as on crystallization processes in the glass during storage at elevated temperatures. Emphasis is placed on the radiation stability of the glasses, based on extensive studies using short-lived actinides (e.g., 244Cm) or ion implantation to produce the damage expected during long storage at an accelerated rate. The radiation stability is shown to be very good, if realistic damage conditions are used. The knowledge accumulated in the past years is used to evaluate and predict the long-term evolution of the glass under storage conditions.

The effect of clay on the dissolution of nuclear waste glass

NASA Astrophysics Data System (ADS)

Lemmens, K.

2001-09-01

In a nuclear waste repository, the waste glass can interact with metals, backfill materials (if present) and natural host rock. Of the various host rocks considered, clays are often reported to delay the onset of the apparent glass saturation, where the glass dissolution rate becomes very small. This effect is ascribed to the sorption of silica or other glass components on the clay. This can have two consequences: (1) the decrease of the silica concentration in solution increases the driving force for further dissolution of glass silica, and (2) the transfer of relatively insoluble glass components (mainly silica) from the glass surface to the clay makes the alteration layer less protective. In recent literature, the latter explanation has gained credibility. The impact of the environmental materials on the glass surface layers is however not well understood. Although the glass dissolution can initially be enhanced by clay, there are arguments to assume that it will decrease to very low values after a long time. Whether this will indeed be the case, depends on the fate of the released glass components in the clay. If they are sorbed on specific sites, it is likely that saturation of the clay will occur. If however the released glass components are removed by precipitation (growth of pre-existing or new secondary phases), saturation of the clay is less likely, and the process can continue until exhaustion of one of the system components. There are indications that the latter mechanism can occur for varying glass compositions in Boom Clay and FoCa clay. If sorption or precipitation prevents the formation of protective surface layers, the glass dissolution can in principle proceed at a high rate. High silica concentrations are assumed to decrease the dissolution rate (by a solution saturation effect or by the impact on the properties of the glass alteration layer). In glass corrosion tests at high clay concentrations, silica concentrations are, however, often higher than the silica concentrations in equilibrium with the glass surface ( C ∗Si, saturation) that are found in absence of clay. Nevertheless, the glass dissolution proceeds at relatively high rate. C ∗Si, saturation seems to be increased by the presence of clay. To understand this, more knowledge is necessary concerning the fate of the released silica and the silica speciation in solution.

Effect of Loading Rate and Surface Conditions on Flexural Strength of Borosilicate Glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nie, X; Chen, Wayne; Wereszczak, Andrew A

2009-01-01

This study evaluates the loading rate and surface condition dependence of the flexural strength of a borosilicate glass. The glass specimens are subjected to three different surface treatments before four-point bending tests to study the effect of surface flaws. Quasistatic (Material Test System 810) and dynamic (Kolsky bar) experiments are performed at loading rates ranging from 0.7 to 4 x 10{sup 6} MPa/s. The results show that the flexural strength of the borosilicate glass has a strong dependence on the loading rate. A chemically etched surface produces an enhanced flexural strength by about an order of magnitude. Scanning electron microscopymore » images on fracture surfaces indicate that the failure is governed by different types of flaws under different surface treatment conditions. Edge failure is also identified for samples possessing high flexural strength.« less

Structure, crystallization and dielectric resonances in 2-13 GHz of waste-derived glass-ceramic

NASA Astrophysics Data System (ADS)

Yao, Rui; Liao, SongYi; Chen, XiaoYu; Wang, GuangRong; Zheng, Feng

2016-12-01

Structure, kinetics of crystallization, and dielectric resonances of waste-derived glass-ceramic prepared via quench-heating route were studied as a function of dosage of iron ore tailing (IOT) within 20-40 wt% using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and vector network analyzer (VNA) measurements. The glass-ceramic mainly consisted of ferrite crystals embedded in borosilicate glass matrix. Crystallization kinetics and morphologies of ferrite crystals as well as coordination transformation of boron between [BO4] and [BO3] in glass network were adjustable by changing the amount of IOT. Dielectric resonances in 6-13 GHz were found to be dominated by oscillations of Ca2+ cations in glass network with [SiO4] units on their neighboring sites. Ni2+ ions made a small contribution to those resonances. Diopside formed when IOT exceeded 35 wt%, which led to weakening of the resonances.

Production of glass-ceramics from sewage sludge and waste glass

NASA Astrophysics Data System (ADS)

Rozenstrauha, I.; Sosins, G.; Petersone, L.; Krage, L.; Drille, M.; Filipenkov, V.

2011-12-01

In the present study for recycling of sewage sludge and waste glass from JSC "Valmieras stikla skiedra" treatment of them to the dense glass-ceramic composite material using powder technology is estimated. The physical-chemical properties of composite materials were identified - density 2.19 g/cm3, lowest water absorption of 2.5% and lowest porosity of 5% for the samples obtained in the temperature range of sintering 1120 - 1140 °C. Regarding mineralogical composition of glass-ceramics the following crystalline phases were identified by XRD analysis: quartz (SiO2), anorthite (CaAl2Si2O8) and hematite (Fe2O3), which could ensure the high density of materials and improve the mechanical properties of material - compressive strength up to 60.31±5.09 - 52.67±19.18 MPa. The physical-chemical properties of novel materials corresponds to dense glass-ceramics composite which eventually could be used as a building material, e.g. for floor covering, road pavement, exterior tiles etc.

Leaves Waste Composite with Glass Fiber Reinforcement

NASA Astrophysics Data System (ADS)

Khoiri, N.; Jannah, W. N.; Huda, C.; Maulana, RM; Marwoto, P.; Masturi

2018-03-01

A research has been made to fabricate leave waste composites and Polyvinyl Acetate (PvAc) polymers reinforced with glass fibers. The method used was a simple mixing of leaves powders, PvAc, and glass fibers varied from 0 g to 1 g. Mass of 16 g leaves powder and mass of PvAc 4 g. The mixing result is suppressed by 5 metric-tons for 15 minutes. The composite is dried at room temperature for 1 day then in the oven at 100°C for 1 hour. The compressive strength is measured bu a hydraulic press. The result show that the compressive strength increased to the highest point of 0.8 g and will decrease significantly when the addition of glass fiber mass of 1 g. The highest compressive strength reaches 52.6 MPa when the glass fiber mass is 0.8 g. The result of this research showed that leaves composites with Polyvinyl Acetate polymer reinforced with fiber glass can be used as alternative material of wood substitute.

Agricultural wastes as a resource of raw materials for developing low-dielectric glass-ceramics

PubMed Central

Danewalia, Satwinder Singh; Sharma, Gaurav; Thakur, Samita; Singh, K.

2016-01-01

Agricultural waste ashes are used as resource materials to synthesize new glass and glass-ceramics. The as-prepared materials are characterized using various techniques for their structural and dielectric properties to check their suitability in microelectronic applications. Sugarcane leaves ash exhibits higher content of alkali metal oxides than rice husk ash, which reduces the melting point of the components due to eutectic reactions. The addition of sugarcane leaves ash in rice husk ash promotes the glass formation. Additionally, it prevents the cristobalite phase formation. These materials are inherently porous, which is responsible for low dielectric permittivity i.e. 9 to 40. The presence of less ordered augite phase enhances the dielectric permittivity as compared to cristobalite and tridymite phases. The present glass-ceramics exhibit lower losses than similar materials synthesized using conventional minerals. The dielectric permittivity is independent to a wide range of temperature and frequency. The glass-ceramics developed with adequately devitrified phases can be used in microelectronic devices and other dielectric applications. PMID:27087123

Clean option: An alternative strategy for Hanford Tank Waste Remediation. Volume 2, Detailed description of first example flowsheet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swanson, J.L.

1993-09-01

Disposal of high-level tank wastes at the Hanford Site is currently envisioned to divide the waste between two principal waste forms: glass for the high-level waste (HLW) and grout for the low-level waste (LLW). The draft flow diagram shown in Figure 1.1 was developed as part of the current planning process for the Tank Waste Remediation System (TWRS), which is evaluating options for tank cleanup. The TWRS has been established by the US Department of Energy (DOE) to safely manage the Hanford tank wastes. It includes tank safety and waste disposal issues, as well as the waste pretreatment and wastemore » minimization issues that are involved in the ``clean option`` discussed in this report. This report describes the results of a study led by Pacific Northwest Laboratory to determine if a more aggressive separations scheme could be devised which could mitigate concerns over the quantity of the HLW and the toxicity of the LLW produced by the reference system. This aggressive scheme, which would meet NRC Class A restrictions (10 CFR 61), would fit within the overall concept depicted in Figure 1.1; it would perform additional and/or modified operations in the areas identified as interim storage, pretreatment, and LLW concentration. Additional benefits of this scheme might result from using HLW and LLW disposal forms other than glass and grout, but such departures from the reference case are not included at this time. The evaluation of this aggressive separations scheme addressed institutional issues such as: radioactivity remaining in the Hanford Site LLW grout, volume of HLW glass that must be shipped offsite, and disposition of appropriate waste constituents to nonwaste forms.« less

Progress toward bridging from atomistic to continuum modeling to predict nuclear waste glass dissolution.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zapol, Peter; Bourg, Ian; Criscenti, Louise Jacqueline

2011-10-01

This report summarizes research performed for the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Subcontinuum and Upscaling Task. The work conducted focused on developing a roadmap to include molecular scale, mechanistic information in continuum-scale models of nuclear waste glass dissolution. This information is derived from molecular-scale modeling efforts that are validated through comparison with experimental data. In addition to developing a master plan to incorporate a subcontinuum mechanistic understanding of glass dissolution into continuum models, methods were developed to generate constitutive dissolution rate expressions from quantum calculations, force field models were selected to generate multicomponent glass structures and gel layers,more » classical molecular modeling was used to study diffusion through nanopores analogous to those in the interfacial gel layer, and a micro-continuum model (K{mu}C) was developed to study coupled diffusion and reaction at the glass-gel-solution interface.« less

Waste canister for storage of nuclear wastes

DOEpatents

Duffy, James B.

1977-01-01

A waste canister for storage of nuclear wastes in the form of a solidified glass includes fins supported from the center with the tips of the fins spaced away from the wall to conduct heat away from the center without producing unacceptable hot spots in the canister wall.

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation of non-recyclable wastes (e.g., polychlorinated biphenyl... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Waste management plan. 60.55c Section...

The applicability of different waste materials for the production of lightweight aggregates.

PubMed

Ducman, V; Mirtic, B

2009-08-01

The applicability of different waste materials for the production of lightweight aggregates has been studied. The following waste materials were investigated: silica sludge, superfluous clay in the quarry, waste glass, and residue from the polishing process of different types of stone. SiC and MnO(2) were selected as foaming agents. Feldspar containing minerals and scrap glass were added in order to lower the softening point of the waste materials. The granules were prepared by mixing together finely ground waste with one or both of the selected foaming agents. The granules were then fired at different temperatures above the softening point of the glassy phase within the temperature range from 1150 to 1220 degrees C, where the foaming agent degasses, and the resulting gasses remain trapped in the glassy structure. The foaming process was observed by hot-stage microscopy. The properties of the so-obtained granules, such as their apparent density and compressive strength, were determined, and their microstructures were evaluating using SEM and polarizing microscopy. With the addition to clay of polishing residue from granite-like rocks, after firing at 1220 degrees C homogeneously porous granules with a density down to 0.42 g/cm(3) were obtained, whereas with the addition to waste silica sludge of polishing residue from granite-like rocks and waste glass with a foaming agent, after firing at 1220 degrees C densities from 0.57 to 0.82 g/cm(3) were obtained.

Assessment, development, and testing of glass for blast environments.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glass, Sarah Jill

2003-06-01

Glass can have lethal effects including fatalities and injuries when it breaks and then flies through the air under blast loading (''the glass problem''). One goal of this program was to assess the glass problem and solutions being pursued to mitigate it. One solution to the problem is the development of new glass technology that allows the strength and fragmentation to be controlled or selected depending on the blast performance specifications. For example the glass could be weak and fail, or it could be strong and survive, but it must perform reliably. Also, once it fails it should produce fragmentsmore » of a controlled size. Under certain circumstances it may be beneficial to have very small fragments, in others it may be beneficial to have large fragments that stay together. The second goal of this program was to evaluate the performance (strength, reliability, and fragmentation) of Engineered Stress Profile (ESP) glass under different loading conditions. These included pseudo-static strength and pressure tests and free-field blast tests. The ultimate goal was to provide engineers and architects with a glass whose behavior under blast loading is less lethal. A near-term benefit is a new approach for improving the reliability of glass and modifying its fracture behavior.« less

Effect of sintering temperature on the microstructure and properties of foamed glass-ceramics prepared from high-titanium blast furnace slag and waste glass

NASA Astrophysics Data System (ADS)

Chen, Chang-hong; Feng, Ke-qin; Zhou, Yu; Zhou, Hong-ling

2017-08-01

Foamed glass-ceramics were prepared via a single-step sintering method using high-titanium blast furnace slag and waste glass as the main raw materials The influence of sintering temperature (900-1060°C) on the microstructure and properties of foamed glass-ceramics was studied. The results show that the crystal shape changed from grainy to rod-shaped and finally turned to multiple shapes as the sintering temperature was increased from 900 to 1060°C. With increasing sintering temperature, the average pore size of the foamed glass-ceramics increased and subsequently decreased. By contrast, the compressive strength and the bulk density decreased and subsequently increased. An excessively high temperature, however, induced the coalescence of pores and decreased the compressive strength. The optimal properties, including the highest compressive strength (16.64 MPa) among the investigated samples and a relatively low bulk density (0.83 g/cm3), were attained in the case of the foamed glass-ceramics sintered at 1000°C.

The recycling of comminuted glass-fiber-reinforced resin from electronic waste.

PubMed

Duan, Huabo; Jia, Weifeng; Li, Jinhui

2010-05-01

The reuse of comminuted glass-fiber-reinforced resin with various granularities gathered from printed circuit manufacturing residues was investigated. As fillers, these residues were converted into polymeric composite board by an extrusion and injection process using polypropylene as a bonding agent. The mechanical properties of the reproduced composite board were examined by considering the effects of mass fraction and glass-fiber distribution. Interfacial-layer micrograph analysis of the composite material fracture surface was used to study the fiber reinforcement mechanism. Results showed that using comminuted glass-fiber-reinforced resin as a filler material greatly enhanced the performance properties of the composite board. Although the length and diameter of filler varied, these variations had no appreciable effect on the mechanical properties of the processed board. Maximum values of 48.30 MPa for flexural strength, 31.34 MPa for tensile strength, and 31.34 J/m for impact strength were achieved from a composite board containing mass fractions of 30, 10, and 20% glass-fiber-reinforced resin waste, respectively. It was found that the maximum amount of recyclate that could be added to a composite board was 30% of weight. Beyond these percentages, the materials blend became unmanageable and the mixture less amenable to impregnation with fiber. Presented studies indicated that comminuted glass-fiber-reinforced resin waste-filled polypropylene composites are promising candidates for structural applications where high stiffness and fracture resistance are required.

Modelling the local atomic structure of molybdenum in nuclear waste glasses with ab initio molecular dynamics simulations.

PubMed

Konstantinou, Konstantinos; Sushko, Peter V; Duffy, Dorothy M

2016-09-21

The nature of chemical bonding of molybdenum in high level nuclear waste glasses has been elucidated by ab initio molecular dynamics simulations. Two compositions, (SiO 2 ) 57.5 -(B 2 O 3 ) 10 -(Na 2 O) 15 -(CaO) 15 -(MoO 3 ) 2.5 and (SiO 2 ) 57.3 -(B 2 O 3 ) 20 -(Na 2 O) 6.8 -(Li 2 O) 13.4 -(MoO 3 ) 2.5 , were considered in order to investigate the effect of ionic and covalent components on the glass structure and the formation of the crystallisation precursors (Na 2 MoO 4 and CaMoO 4 ). The coordination environments of Mo cations and the corresponding bond lengths calculated from our model are in excellent agreement with experimental observations. The analysis of the first coordination shell reveals two different types of molybdenum host matrix bonds in the lithium sodium borosilicate glass. Based on the structural data and the bond valence model, we demonstrate that the Mo cation can be found in a redox state and the molybdate tetrahedron can be connected with the borosilicate network in a way that inhibits the formation of crystalline molybdates. These results significantly extend our understanding of bonding in Mo-containing nuclear waste glasses and demonstrate that tailoring the glass composition to specific heavy metal constituents can facilitate incorporation of heavy metals at high concentrations.

Flexible Bionanocomposites from Epoxidized Hemp Seed Oil Thermosetting Resin Reinforced with Halloysite Nanotubes.

PubMed

Shuttleworth, Peter S; Díez-Pascual, Ana M; Marco, Carlos; Ellis, Gary

2017-03-23

Hemp seed (Cannabis sativa L.) oil comprises a variety of beneficial unsaturated triglycerides with well-documented nutritional and health benefits. However, it can become rancid over a relatively short time period, leading to increased industrial costs and waste of a valuable product. The development of sustainable polymers is presented as a strategy, where both the presence of unsaturation and peroxide content could be effectively used to alleviate both the waste and financial burden. After the reaction with peroxyacetic acid, the incorporation of halloysite nanotubes (HNTs), and the subsequent thermal curing, without the need for organic solvents or interfacial modifiers, flexible transparent materials with a low glass-transition temperature were developed. The improvement in the thermal stability and both the static and dynamic mechanical properties of the bionanocomposites were significantly enhanced with the well-dispersed HNT filler. At an optimum concentration of 0.5 wt % HNTs, a simultaneous increase in stiffness, strength, ductility, and toughness was observed in comparison to the unfilled cured resin. These sustainable food-waste-derived bionanocomposites may provide an interesting alternative to petroleum-based materials, particularly for low-load-bearing applications, such as packaging.

Frequent Questions About the Regulation of Used Cathode Ray Tubes (CRTs) and CRT Glass

EPA Pesticide Factsheets

Frequent questions such as Which materials are covered by the CRT exclusion?, How does U.S. EPA regulate recycling of used CRTs and CRT glass under the RCRA hazardous waste regulations?, What export requirements apply to CRTs and CRT glass?

METHODS OF ANALYSIS FOR WASTE LOAD ALLOCATION

EPA Science Inventory

This research has addressed several unresolved questions concerning the allocation of allowable waste loads among multiple wastewater dischargers within a water quality limited stream segment. First, the traditional assumptions about critical design conditions for waste load allo...

Glass and Glass-Ceramic Materials from Simulated Composition of Lunar and Martian Soils: Selected Properties and Potential Applications

NASA Technical Reports Server (NTRS)

Ray, C. S.; Sen, S.; Reis, S. T.; Kim, C. W.

2005-01-01

In-situ resource processing and utilization on planetary bodies is an important and integral part of NASA's space exploration program. Within this scope and context, our general effort is primarily aimed at developing glass and glass-ceramic type materials using lunar and martian soils, and exploring various applications of these materials for planetary surface operations. Our preliminary work to date have demonstrated that glasses can be successfully prepared from melts of the simulated composition of both lunar and martian soils, and the melts have a viscosity-temperature window appropriate for drawing continuous glass fibers. The glasses are shown to have the potential for immobilizing certain types of nuclear wastes without deteriorating their chemical durability and thermal stability. This has a direct impact on successfully and economically disposing nuclear waste generated from a nuclear power plant on a planetary surface. In addition, these materials display characteristics that can be manipulated using appropriate processing protocols to develop glassy or glass-ceramic magnets. Also discussed in this presentation are other potential applications along with a few selected thermal, chemical, and structural properties as evaluated up to this time for these materials.

Initial Radionuclide Inventories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, H

The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclearmore » fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement, currently identified as 2030 and 2033, depending on the type of waste. TSPA-LA uses the results of this analysis to decay the inventory to the year of repository closure projected for the year of 2060.« less

Ancient Glass: A Literature Search and its Role in Waste Management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strachan, Denis M.; Pierce, Eric M.

2010-07-01

When developing a performance assessment model for the long-term disposal of immobilized low-activity waste (ILAW) glass, it is desirable to determine the durability of glass forms over very long periods of time. However, testing is limited to short time spans, so experiments are performed under conditions that accelerate the key geochemical processes that control weathering. Verification that models currently being used can reliably calculate the long term behavior ILAW glass is a key component of the overall PA strategy. Therefore, Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to evaluate alternative strategies that can be usedmore » for PA source term model validation. One viable alternative strategy is the use of independent experimental data from archaeological studies of ancient or natural glass contained in the literature. These results represent a potential independent experiment that date back to approximately 3600 years ago or 1600 before the current era (bce) in the case of ancient glass and 106 years or older in the case of natural glass. The results of this literature review suggest that additional experimental data may be needed before the result from archaeological studies can be used as a tool for model validation of glass weathering and more specifically disposal facility performance. This is largely because none of the existing data set contains all of the information required to conduct PA source term calculations. For example, in many cases the sediments surrounding the glass was not collected and analyzed; therefore having the data required to compare computer simulations of concentration flux is not possible. This type of information is important to understanding the element release profile from the glass to the surrounding environment and provides a metric that can be used to calibrate source term models. Although useful, the available literature sources do not contain the required information needed to simulate the long-term performance of nuclear waste glasses in a near-surface or deep geologic repositories. The information that will be required include 1) experimental measurements to quantify the model parameters, 2) detailed analyses of altered glass samples, and 3) detailed analyses of the sediment surrounding the ancient glass samples.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.

Here, this paper provides an overview of research evaluating the use of lead tellurite glass as a waste form for salt wastes from electrochemical reprocessing of used nuclear fuel. The efficacy of using lead tellurite glass to immobilize three different salt compositions was evaluated: a LiCl-Li 2O oxide reduction salt containing fission products from oxide fuel, a LiCl-KCl eutectic salt containing fission products from metallic fuel, and SrCl 2. Physical and chemical properties of glasses made with these salts were characterized with X-ray diffraction, bulk density measurements, differential thermal analysis, chemical durability tests, scanning and transmission electron microscopies, and energy-dispersivemore » X-ray spectroscopy. These glasses were found to accommodate high salt concentrations and have high densities, but further development is needed to improve chemical durability.« less

DWPF Safely Dispositioning Liquid Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2016-01-05

The only operating radioactive waste glassification plant in the nation, the Defense Waste Processing Facility (DWPF) converts the liquid radioactive waste currently stored at the Savannah River Site (SRS) into a solid glass form suitable for long-term storage and disposal. Scientists have long considered this glassification process, called “vitrification,” as the preferred option for treating liquid radioactive waste.

Alteration layer formation of Ca- and Zn-oxide bearing alkali borosilicate glasses for immobilisation of UK high level waste: A vapour hydration study

NASA Astrophysics Data System (ADS)

Cassingham, N. J.; Corkhill, C. L.; Stennett, M. C.; Hand, R. J.; Hyatt, N. C.

2016-10-01

The UK high level nuclear waste glass modified with CaO/ZnO was investigated using the vapour phase hydration test, performed at 200 °C, with the aim of understanding the impact of the modification on the chemical composition and microstructure of the alteration layer. Experiments were undertaken on non-modified and CaO/ZnO-modified base glass, with or without 25 wt% of simulant Magnox waste calcine. The modification resulted in a dramatic reduction in gel layer thickness and also a reduction in the reaction rate, from 3.4 ± 0.3 g m-2 d-1 without CaO/ZnO modification to 0.9 ± 0.1 g m-2 d-1 with CaO/ZnO. The precipitated phase assemblage for the CaO/ZnO-modified compositions was identified as hydrated Ca- and Zn-bearing silicate phases, which were absent from the non-modified counterpart. These results are in agreement with other recent studies showing the beneficial effects of ZnO additions on glass durability.

Effects of Quartz Particle Size and Sucrose Addition on Melting Behavior of a Melter Feed for High-Level Waste Glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcial, Jose; Hrma, Pavel R; Schweiger, Michael J

2010-08-11

The behavior of melter feed (a mixture of nuclear waste and glass-forming additives) during waste-glass processing has a significant impact on the rate of the vitrification process. We studied the effects of silica particle size and sucrose addition on the volumetric expansion (foaming) of a high-alumina feed and the rate of dissolution of silica particles in feed samples heated at 5°C/min up to 1200°C. The initial size of quartz particles in feed ranged from 5 to 195 µm. The fraction of the sucrose added ranged from 0 to 0.20 g per g glass. Extensive foaming occurred only in feeds withmore » 5-μm quartz particles; particles >150 µm formed clusters. Particles of 5 µm completely dissolved by 900°C whereas particles >150 µm did not fully dissolve even when the temperature reached 1200°C. Sucrose addition had virtually zero impact on both foaming and the dissolution of silica particles.« less

CAD/CAM glass ceramics for single-tooth implant crowns: a finite element analysis.

PubMed

Akça, Kvanç; Cavusoglu, Yeliz; Sagirkaya, Elcin; Aybar, Buket; Cehreli, Murat Cavit

2013-12-01

To evaluate the load distribution of CAD/CAM mono-ceramic crowns supported with single-tooth implants in functional area. A 3-dimensional numerical model of a soft tissue-level implant was constructed with cement-retained abutment to support glass ceramic machinable crown. Implant-abutment complex and the retained crown were embedded in a Ø 1.5 × 1.5 cm geometric matrix for evaluation of mechanical behavior of mono-ceramic CAD/CAM aluminosilicate and leucite glass crown materials. Laterally positioned axial load of 300 N was applied on the crowns. Resulting principal stresses in the mono-ceramic crowns were evaluated in relation to different glass ceramic materials. The highest compressive stresses were observed at the cervical region of the buccal aspect of the crowns and were 89.98 and 89.99 MPa, for aluminosilicate and leucite glass ceramics, respectively. The highest tensile stresses were observed at the collar of the lingual part of the crowns and were 24.54 and 25.39 MPa, respectively. Stresses induced upon 300 N static loading of CAD/CAM aluminosalicate and leucite glass ceramics are below the compressive strength of the materials. Impact loads may actuate the progress to end failure of mono-ceramic crowns supported by metallic implant abutments.

In vitro bioactivity, cytocompatibility, and antibiotic release profile of gentamicin sulfate-loaded borate bioactive glass/chitosan composites.

PubMed

Cui, Xu; Gu, Yifei; Li, Le; Wang, Hui; Xie, Zhongping; Luo, Shihua; Zhou, Nai; Huang, Wenhai; Rahaman, Mohamed N

2013-10-01

Borate bioactive glass-based composites have been attracting interest recently as an osteoconductive carrier material for local antibiotic delivery. In the present study, composites composed of borate bioactive glass particles bonded with a chitosan matrix were prepared and evaluated in vitro as a carrier for gentamicin sulfate. The bioactivity, degradation, drug release profile, and compressive strength of the composite carrier system were studied as a function of immersion time in phosphate-buffered saline at 37 °C. The cytocompatibility of the gentamicin sulfate-loaded composite carrier was evaluated using assays of cell proliferation and alkaline phosphatase activity of osteogenic MC3T3-E1 cells. Sustained release of gentamicin sulfate occurred over ~28 days in PBS, while the bioactive glass converted continuously to hydroxyapatite. The compressive strength of the composite loaded with gentamicin sulfate decreased from the as-fabricated value of 24 ± 3 MPa to ~8 MPa after immersion for 14 days in PBS. Extracts of the soluble ionic products of the borate glass/chitosan composites enhanced the proliferation and alkaline phosphatase activity of MC3T3-E1 cells. These results indicate that the gentamicin sulfate-loaded composite composed of chitosan-bonded borate bioactive glass particles could be useful clinically as an osteoconductive carrier material for treating bone infection.

Chemical Composition Analysis and Product Consistency Tests of the ORP Phase 5 Nepheline Study Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Edwards, T. B.; Caldwell, M. E.

In this report, the Savannah River National Laboratory (SRNL) provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high-level waste glass compositions fabricated by the Pacific Northwest National Laboratory (PNNL). These data will be used in the development of improved models for the prediction of nepheline crystallization in support of the Hanford Tank Waste Treatment and Immobilization Plant (WTP).

Durability of Waste Glass Flax Fiber Reinforced Mortar

NASA Astrophysics Data System (ADS)

Aly, M.; Hashmi, M. S. J.; Olabi, A. G.; Messeiry, M.

2011-01-01

The main concern for natural fibre reinforced mortar composites is the durability of the fibres in the alkaline environment of cement. The composites may undergo a reduction in strength as a result of weakening of the fibres by a combination of alkali attack and fibre mineralisation. In order to enhance the durability of natural fiber reinforced cement composites several approaches have been studied including fiber impregnation, sealing of the matrix pore system and reduction of matrix alkalinity through the use of pozzolanic materials. In this study waste glass powder was used as a pozzolanic additive to improve the durability performance of flax fiber reinforced mortar (FFRM). The durability of the FFRM was studied by determining the effects of ageing in water and exposure to wetting and drying cycles; on the microstructures and flexural behaviour of the composites. The mortar tests demonstrated that the waste glass powder has significant effect on improving the durability of FFRM.

Immobilization of LiCl-Li2O pyroprocessing salt wastes in chlorosodalite using glass-bonded hydrothermal and salt-occlusion methods

NASA Astrophysics Data System (ADS)

Riley, Brian J.; Peterson, Jacob A.; Kroll, Jared O.; Frank, Steven M.

2018-04-01

In this study, hydrothermal and salt-occlusion processes were used to make chlorosodalite through reactions with a high-LiCl salt simulating a waste stream generated from pyrochemical treatment of oxide-based used nuclear fuel. Some products were reacted with glass binders to increase chlorosodalite yield through alkali ion exchange and to aid in densification. Hydrothermal processes included reaction of the salt simulant in an autoclave with either zeolite 4A or sodium aluminate and colloidal silica. Chlorosodalite yields in the crystalline products were nearly complete in the glass-bonded materials at values of 100 mass% for the salt-occlusion method, up to 99.0 mass% for the hydrothermal synthesis with zeolite 4A, and up to 96 mass% for the hydrothermal synthesis with sodium aluminate and colloidal silica. These results show promise for using chemically stable chlorosodalite to immobilize oxide reduction salt wastes.

Glass ceramic obtained by tailings and tin mine waste reprocessing from Llallagua, Bolivia

NASA Astrophysics Data System (ADS)

Arancibia, Jony Roger Hans; Villarino, Cecilia; Alfonso, Pura; Garcia-Valles, Maite; Martinez, Salvador; Parcerisa, David

2014-05-01

In Bolivia Sn mining activity produces large tailings of SiO2-rich residues. These tailings contain potentially toxic elements that can be removed into the surface water and produce a high environmental pollution. This study determines the thermal behaviour and the viability of the manufacture of glass-ceramics from glass. The glass has been obtained from raw materials representative of the Sn mining activities from Llallagua (Bolivia). Temperatures of maximum nucleation rate (Tn) and crystallization (Tcr) were calculated from the differential thermal analyses. The final mineral phases were determined by X-ray diffraction and textures were observed by scanning electron microscopy. Crystalline phases are nefeline occurring with wollastonite or plagioclase. Tn for nepheline is between 680 ºC and 700 ºC, for wollastonite, 730 ºC and for plagioclase, 740 ºC. Tcr for nefeline is between 837 and 965 ºC; for wollastonite, 807 ºC and for plagioclase, 977 ºC. In order to establish the mechanical characteristics and efficiency of the vitrification process in the fixation of potentially toxic elements the resistance to leaching and micro-hardness were determined. The obtained contents of the elements leached from the glass ceramic are well below the limits established by the European legislation. So, these analyses confirm that potentially toxic elements remain fixed in the structure of mineral phases formed in the glass-ceramic process. Regarding the values of micro-hardness results show that they are above those of a commercial glass. The manufacture of glass-ceramics from mining waste reduces the volume of tailings produced for the mining industry and, in turn enhances the waste, transforming it into a product with industrial application. Acknowledgements: This work was partly financed by the project AECID: A3/042750/11, and the SGR 2009SGR-00444.

FY2017 ILAW Glass Corrosion Testing with the Single-Pass Flow-Through Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neeway, James J.; Asmussen, Robert M.; Cordova, Elsa

The inventory of immobilized low-activity waste (ILAW) produced at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) will be disposed of at the near-surface, on-site Integrated Disposal Facility (IDF). When groundwater comes into contact with the waste form, the glass will corrode and radionuclides will be released into the near-field environment. Because the release of the radionuclides is dependent on the dissolution rate of the glass, it is important that the performance assessment (PA) model accounts for the dissolution rate of the glass as a function of various conditions. To accomplish this, an IDF PA glass dissolution model basedmore » on Transition State Theory (TST) can be employed. The model is able to account for changes in temperature, exposed surface area, and pH of the contacting solution as well as the effect of silicon solution concentrations, specifically the activity of orthosilicic acid (H4SiO4), whose concentration is directly linked to the glass dissolution rate. In addition, the IDF PA model accounts for the ion exchange process. The effect of temperature, pH, H4SiO4 activity, and the rate of ion exchange can be parameterized and implemented directly into the PA rate model. The rate model parameters are derived from laboratory tests with the single-pass flow-through (SPFT) method. The provided data can be used by glass researchers to further the understanding of ILAW glass behavior, by IDF PA modelers to use the rate model parameters in PA modeling efforts, and by Department of Energy (DOE) contractors and decision makers as they assess the IDF PA program.« less

Glass-ceramic nuclear waste forms obtained by crystallization of SiO 2-Al 2O 3-CaO-ZrO 2-TiO 2 glasses containing lanthanides (Ce, Nd, Eu, Gd, Yb) and actinides (Th): Study of the crystallization from the surface

NASA Astrophysics Data System (ADS)

Loiseau, P.; Caurant, D.

2010-07-01

Glass-ceramic materials containing zirconolite (nominally CaZrTi 2O 7) crystals in their bulk can be envisaged as potential waste forms for minor actinides (Np, Am, Cm) and Pu immobilization. In this study such matrices are synthesized by crystallization of SiO 2-Al 2O 3-CaO-ZrO 2-TiO 2 glasses containing lanthanides (Ce, Nd, Eu, Gd, Yb) and actinides (Th) as surrogates. A thin partially crystallized layer containing titanite and anorthite (nominally CaTiSiO 5 and CaAl 2Si 2O 8, respectively) growing from glass surface is also observed. The effect of the nature and concentration of surrogates on the structure, the microstructure and the composition of the crystals formed in the surface layer is presented in this paper. Titanite is the only crystalline phase able to significantly incorporate trivalent lanthanides whereas ThO 2 precipitates in the layer. The crystal growth thermal treatment duration (2-300 h) at high temperature (1050-1200 °C) is shown to strongly affect glass-ceramics microstructure. For the system studied in this paper, it appears that zirconolite is not thermodynamically stable in comparison with titanite growing form glass surface. Nevertheless, for kinetic reasons, such transformation (i.e. zirconolite disappearance to the benefit of titanite) is not expected to occur during interim storage and disposal of the glass-ceramic waste forms because their temperature will never exceed a few hundred degrees.

Evaluation of Behaviours of Laminated Glass

NASA Astrophysics Data System (ADS)

Sable, L.; Japins, G.; Kalnins, K.

2015-11-01

Visual appearance of building facades and other load bearing structures, which now are part of modern architecture, is the reason why it is important to investigate in more detail the reliability of laminated glass for civil structures. Laminated glass in particular has become one of the trendy materials, for example Apple© stores have both load carrying capacity and transparent appearance. Glass has high mechanical strength and relatively medium density, however, the risk of sudden brittle failure like concrete or other ceramics determine relatively high conservatism in design practice of glass structures. This should be changed as consumer requirements evolve calling for a safe and reliable design methodology and corresponding building standards. A design methodology for glass and glass laminates should be urgently developed and included as a chapter in Eurocode. This paper presents initial experimental investigation of behaviour of simple glass sheets and laminated glass samples in 4-point bending test. The aim of the current research is to investigate laminated glass characteristic values and to verify the obtained experimental results with finite element method for glass and EVA material in line with future European Structural Design of Glass Components code.

DWPF STARTUP FRIT VISCOSITY MEASUREMENT ROUND ROBIN RESULTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crum, Jarrod V.; Edwards, Tommy B.; Russell, Renee L.

2012-07-31

A viscosity standard is needed to replace the National Institute of Standards and Technology (NIST) glasses currently being used to calibrate viscosity measurement equipment. The current NIST glasses are either unavailable or less than ideal for calibrating equipment to measure the viscosity of high-level waste glasses. This report documents the results of a viscosity round robin study conducted on the Defense Waste Processing Facility (DWPF) startup frit. DWPF startup frit was selected because its viscosity-temperature relationship is similar to most DWPF and Hanford high-level waste glass compositions. The glass underwent grinding and blending to homogenize the large (100 lb) batch.more » Portions of the batch were supplied to the laboratories (named A through H) for viscosity measurements following a specified temperature schedule with a temperature range of 1150 C to 950 C and with an option to measure viscosity at lower temperatures if their equipment was capable of measuring at the higher viscosities. Results were used to fit the Vogel-Tamman-Fulcher and Arrhenius equations to viscosity as a function of temperature for the entire temperature range of 460 C through 1250 C as well as the limited temperature interval of approximately 950 C through 1250 C. The standard errors for confidence and prediction were determined for the fitted models.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cassingham, N.; Corkhill, C. L.; Backhouse, D. J.

The first comprehensive assessment of the dissolution kinetics of simulant Magnox–THORP blended UK high-level waste glass, obtained by performing a range of single-pass flow-through experiments, is reported here. Inherent forward rates of glass dissolution were determined over a temperature range of 23 to 70°C and an alkaline pH range of 8.0 to 12.0. Linear regression techniques were applied to the TST kinetic rate law to obtain fundamental parameters necessary to model the dissolution kinetics of UK high-level waste glass (the activation energy (Ea), pH power law coefficient (η) and the intrinsic rate constant (k0)), which is of importance to themore » post-closure safety case for the geological disposal of vitreous products. The activation energies based on B release ranged from 55 ± 3 to 83 ± 9 kJ mol–1, indicating that Magnox–THORP blend glass dissolution has a surface-controlled mechanism, similar to that of other high- level waste simulant glass compositions such as the French SON68 and LAW in the US. Forward dissolution rates, based on Si, B and Na release, suggested that the dissolution mechanism under dilute conditions, and pH and temperature ranges of this study, was not sensitive to composition as defined by HLW-incorporation rate.« less

Effects of cementation surface modifications on fracture resistance of zirconia.

PubMed

Srikanth, Ramanathan; Kosmac, Tomaz; Della Bona, Alvaro; Yin, Ling; Zhang, Yu

2015-04-01

To examine the effects of glass infiltration (GI) and alumina coating (AC) on the indentation flexural load and four-point bending strength of monolithic zirconia. Plate-shaped (12 mm × 12 mm × 1.0 mm or 1.5 or 2.0 mm) and bar-shaped (4 mm × 3 mm × 25 mm) monolithic zirconia specimens were fabricated. In addition to monolithic zirconia (group Z), zirconia monoliths were glass-infiltrated or alumina-coated on their tensile surfaces to form groups ZGI and ZAC, respectively. They were also glass-infiltrated on their upper surfaces, and glass-infiltrated or alumina-coated on their lower (tensile) surfaces to make groups ZGI2 and ZAC2, respectively. For comparison, porcelain-veneered zirconia (group PVZ) and monolithic lithium disilicate glass-ceramic (group LiDi) specimens were also fabricated. The plate-shaped specimens were cemented onto a restorative composite base for Hertzian indentation using a tungsten carbide spherical indenter with a radius of 3.2mm. Critical loads for indentation flexural fracture at the zirconia cementation surface were measured. Strengths of bar-shaped specimens were evaluated in four-point bending. Glass infiltration on zirconia tensile surfaces increased indentation flexural loads by 32% in Hertzian contact and flexural strength by 24% in four-point bending. Alumina coating showed no significant effect on resistance to flexural damage of zirconia. Monolithic zirconia outperformed porcelain-veneered zirconia and monolithic lithium disilicate glass-ceramics in terms of both indentation flexural load and flexural strength. While both alumina coating and glass infiltration can be used to effectively modify the cementation surface of zirconia, glass infiltration can further increase the flexural fracture resistance of zirconia. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Effects of cementation surface modifications on fracture resistance of zirconia

PubMed Central

Srikanth, Ramanathan; Kosmac, Tomaz; Bona, Alvaro Della; Yin, Ling; Zhang, Yu

2015-01-01

Objectives To examine the effects of glass infiltration (GI) and alumina coating (AC) on the indentation flexural load and four-point bending strength of monolithic zirconia. Methods Plate-shaped (12 mm × 12 mm × 1.0 mm or 1.5 mm or 2.0 mm) and bar-shaped (4 mm × 3 mm × 25 mm) monolithic zirconia specimens were fabricated. In addition to monolithic zirconia (group Z), zirconia monoliths were glass-infiltrated or alumina-coated on their tensile surfaces to form groups ZGI and ZAC, respectively. They were also glass-infiltrated on their upper surfaces, and glass-infiltrated or alumina-coated on their lower (tensile) surfaces to make groups ZGI2 and ZAC2, respectively. For comparison, porcelain-veneered zirconia (group PVZ) and monolithic lithium disilicate glass-ceramic (group LiDi) specimens were also fabricated. The plate-shaped specimens were cemented onto a restorative composite base for Hertzian indentation using a tungsten carbide spherical indenter with a radius of 3.2 mm. Critical loads for indentation flexural fracture at the zirconia cementation surface were measured. Strengths of bar-shaped specimens were evaluated in four-point bending. Results Glass infiltration on zirconia tensile surfaces increased indentation flexural loads by 32% in Hertzian contact and flexural strength by 24% in four-point bending. Alumina coating showed no significant effect on resistance to flexural damage of zirconia. Monolithic zirconia outperformed porcelain-veneered zirconia and monolithic lithium disilicate glass-ceramics in terms of both indentation flexural load and flexural strength. Significance While both alumina coating and glass infiltration can be used to effectively modify the cementation surface of zirconia, glass infiltration can further increase the flexural fracture resistance of zirconia. PMID:25687628

Comparison of the fracture resistances of glass fiber mesh- and metal mesh-reinforced maxillary complete denture under dynamic fatigue loading.

PubMed

Im, So-Min; Huh, Yoon-Hyuk; Cho, Lee-Ra; Park, Chan-Jin

2017-02-01

The aim of this study was to investigate the effect of reinforcing materials on the fracture resistances of glass fiber mesh- and Cr-Co metal mesh-reinforced maxillary complete dentures under fatigue loading. Glass fiber mesh- and Cr-Co mesh-reinforced maxillary complete dentures were fabricated using silicone molds and acrylic resin. A control group was prepared with no reinforcement (n = 15 per group). After fatigue loading was applied using a chewing simulator, fracture resistance was measured by a universal testing machine. The fracture patterns were analyzed and the fractured surfaces were observed by scanning electron microscopy. After cyclic loading, none of the dentures showed cracks or fractures. During fracture resistance testing, all unreinforced dentures experienced complete fracture. The mesh-reinforced dentures primarily showed posterior framework fracture. Deformation of the all-metal framework caused the metal mesh-reinforced denture to exhibit the highest fracture resistance, followed by the glass fiber mesh-reinforced denture ( P <.05) and the control group ( P <.05). The glass fiber mesh-reinforced denture primarily maintained its original shape with unbroken fibers. River line pattern of the control group, dimples and interdendritic fractures of the metal mesh group, and radial fracture lines of the glass fiber group were observed on the fractured surfaces. The glass fiber mesh-reinforced denture exhibits a fracture resistance higher than that of the unreinforced denture, but lower than that of the metal mesh-reinforced denture because of the deformation of the metal mesh. The glass fiber mesh-reinforced denture maintains its shape even after fracture, indicating the possibility of easier repair.

A nanometallic nickel-coated, glass-fibre-based structural health monitoring system for polymer composites

NASA Astrophysics Data System (ADS)

Balaji, R.; Sasikumar, M.

2017-09-01

Glass-fibre-reinforced polymer matrix composites are widely used in various industries because of their unique high strength to weight ratio. Unlike metals, strain-induced and damage states of composites are complicated to predict under real-time loading due to their anisotropic nature. With that focus, a piezoresistive nanomaterial-based structural health monitoring system for laminated polymer composites is proposed to measure the strain induced in the composite under real-time loading. Nanometallic nickel-coated glass fibres are embedded into the polymer composites to monitor the strain and damage induced in them. The nanometallic nickel is coated over the glass fibre by a dip coating technique using epoxy as the binding agent. A microcontroller-based electrical resistance measurement system is used to measure the piezoresistive variation in the coated glass fibre under real-time loading. Using the piezoresistance variation of the embedded nanometallic nickel-coated glass fibre, the real-time strain and damage induced in the composite can be correlated. The piezoresistive response of the coated glass fibre is descibed in two phases, the deformation phase and the failure phase, which clearly show the various states of strain and damage induced in the composites.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abboud, Alexander; Guillen, Donna Post; Pokorny, Richard

At the Hanford site in the state of Washington, more than 56 million gallons of radioactive waste is stored in underground tanks. The cleanup plan for this waste is vitrification at the Waste Treatment Plant (WTP), currently under construction. At the WTP, the waste will be blended with glass-forming materials and heated to 1423K, then poured into stainless steel canisters to cool and solidify. A fundamental understanding of the glass batch melting process is needed to optimize the process to reduce cost and decrease the life cycle of the cleanup effort. The cold cap layer that floats on the surfacemore » of the glass melt is the primary reaction zone for the feed-to-glass conversion. The conversion reactions include water release, melting of salts, evolution of batch gases, dissolution of quartz and the formation of molten glass. Obtaining efficient heat transfer to this region is crucial to achieving high rates of glass conversion. Computational fluid dynamics (CFD) modeling is being used to understand the heat transfer dynamics of the system and provide insight to optimize the process. A CFD model was developed to simulate the DM1200, a pilot-scale melter that has been extensively tested by the Vitreous State Laboratory (VSL). Electrodes are built into the melter to provide Joule heating to the molten glass. To promote heat transfer from the molten glass into the reactive cold cap layer, bubbling of the molten glass is used to stimulate forced convection within the melt pool. A three-phase volume of fluid approach is utilized to model the system, wherein the molten glass and cold cap regions are modeled as separate liquid phases, and the bubbling gas and plenum regions are modeled as one lumped gas phase. The modeling of the entire system with a volume of fluid model allows for the prescription of physical properties on a per-phase basis. The molten glass phase and the gas phase physical properties are obtained from previous experimental work. Finding representative properties for the cold cap region is more difficult, as this region is not a true liquid, but rather a multilayer region consisting of a porous and a foamy layer. Physical properties affecting heat transfer, namely the thermal conductivity and heat capacity, have been fit to closely match data and observations from laboratory experiments. Data from xray tomography and quenching of laboratory-scale cold caps provide insight into the topology of bubble distribution within the cold cap at various temperatures. Heat transfer within the melter was validated by comparison with VSL data for the pilot-scale melter.« less

DWPF Safely Dispositioning Liquid Waste

ScienceCinema

None

2018-06-21

The only operating radioactive waste glassification plant in the nation, the Defense Waste Processing Facility (DWPF) converts the liquid radioactive waste currently stored at the Savannah River Site (SRS) into a solid glass form suitable for long-term storage and disposal. Scientists have long considered this glassification process, called “vitrification,” as the preferred option for treating liquid radioactive waste.

Supplemental Immobilization of Hanford Low-Activity Waste: Cast Stone Screening Tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westsik, Joseph H.; Piepel, Gregory F.; Lindberg, Michael J.

2013-09-30

More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in themore » HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second LAW immobilization facility will be needed for the expected volume of LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with the waste acceptance criteria for the disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF. The PA is needed to satisfy both Washington State IDF Permit and DOE Order requirements. Cast Stone has been selected for solidification of radioactive wastes including WTP aqueous secondary wastes treated at the Effluent Treatment Facility (ETF) at Hanford. A similar waste form called Saltstone is used at the Savannah River Site (SRS) to solidify its LAW tank wastes.« less

Proof Test Diagrams for a Lithia-Alumina-Silica Glass-Ceramic

NASA Technical Reports Server (NTRS)

Tucker, Dennis S.

2003-01-01

The glass-ceramic (Zerodur, Schott Glaswerke, Mainz, Germany) contains 70% to 78% by weight crystalline phase of high-quartz structure with a mean crystal size of 50-55 nm. The vitreous phase has a positive thermal expansion coefficient which is practically balanced by the negative coefficient of the crystalline phase. This results in a material which can maintain longitudinal stability during thermal cycling. This was one of the reasons for its choice as the material for the grazing incidence mirrors for the Chandra X-Ray Facility. Brittle materials such as glass and glass-ceramics which exhibit slow crack growth and subsequent fast fracture to failure exhibit a time dependence in strength. The decrease in strength for a constant applied load is known as static fatigue. In many cases, environment plays a major role in the material lifetime. It has been shown for silicate glasses that crack velocity will increase as the amount of water vapor in the environment surface finish and rate of loading. A rough surface finish leads to a lower tensile strength than for an optically polished surface. The strength of glass is observed in general to increase with increasing load rate. This phenomena is known as dynamic fatigue. This was observed for Zerodur by Tucker and Gent and Tucker in previous dynamic fatigue studies, in which lifetimes were obtained. All of the above named factors need to be considered when glass is to be used in load bearing applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.

This paper provides an overview of research evaluating the use of lead tellurite glass as a waste form for salt wastes from electrochemical reprocessing of used nuclear fuel. The efficacy of using lead tellurite glass to immobilize three different salt compositions was evaluated: a LiCl-Li2O oxide reduction salt containing fission products from oxide fuel, a LiCl-KCl eutectic salt containing fission products from metallic fuel, and SrCl2. Physical and chemical properties of glasses made with these salts were characterized with X-ray diffraction, bulk density measurements, differential thermal analysis, chemical durability tests, scanning and transmission electron microscopies, and energy-dispersive X-ray spectroscopy. Thesemore » glasses were found to accommodate high salt concentrations and have high densities, but further development is needed to improve chemical durability. (C) 2017 Published by Elsevier B.V.« less

75 FR 41850 - Amended Notice of Intent to Modify the Scope of the Surplus Plutonium Disposition Supplemental...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-19

... immobilization). Also, DOE had identified a glass can-in-canister immobilization approach as its preferred... allow immobilization of some or all of the surplus plutonium in glass or ceramic material for disposal... in canisters to be filled with borosilicate glass containing intensely radioactive high-level waste...

Hanford High-Level Waste Vitrification Program at the Pacific Northwest National Laboratory: technology development - annotated bibliography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larson, D.E.

1996-09-01

This report provides a collection of annotated bibliographies for documents prepared under the Hanford High-Level Waste Vitrification (Plant) Program. The bibliographies are for documents from Fiscal Year 1983 through Fiscal Year 1995, and include work conducted at or under the direction of the Pacific Northwest National Laboratory. The bibliographies included focus on the technology developed over the specified time period for vitrifying Hanford pretreated high-level waste. The following subject areas are included: General Documentation; Program Documentation; High-Level Waste Characterization; Glass Formulation and Characterization; Feed Preparation; Radioactive Feed Preparation and Glass Properties Testing; Full-Scale Feed Preparation Testing; Equipment Materials Testing; Meltermore » Performance Assessment and Evaluations; Liquid-Fed Ceramic Melter; Cold Crucible Melter; Stirred Melter; High-Temperature Melter; Melter Off-Gas Treatment; Vitrification Waste Treatment; Process, Product Control and Modeling; Analytical; and Canister Closure, Decontamination, and Handling« less

Materials for Tc Capture to Increase Tc Retention in Glass Waste Form

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luksic, Steven A.; Hrma, Pavel R.; Kruger, Albert A.

99Technetium is a long-lived fission product found in the tank waste at the Hanford site in Washington State. In its heptavalent species, it is volatile at the temperatures used in Hanford Tank Waste Treatment and Immobilization Plant vitrification melters, and thus is challenging to incorporate into waste glass. In order to decrease volatility and thereby increase retention, technetium can be converted into more thermally stable species. Several mineral phases, such as spinel, are able to incorporate tetravalent technetium in a chemically durable and thermally stable lattice, and these hosts may promote the decreased volatility that is desired. In order tomore » be usefully implemented, there must be a synthetic rout to these phases that is compatible with both technetium chemistry and current Hanford Tank Waste Treatment and Immobilization Plant design. Synthetic routes for spinel and other potential host phases are examined.« less

Fiber optic thermal/fast neutron and gamma ray scintillation detector

DOEpatents

Neal, John S.; Mihalczo, John T.

2006-11-28

A detector system that combines a .sup.6Li loaded glass fiber scintillation thermal neutron detector with a fast scintillation detector in a single layered structure. Detection of thermal and fast neutrons and ionizing electromagnetic radiation is achieved in the unified detector structure. The fast scintillator replaces the polyethelene moderator layer adjacent the .sup.6Li loaded glass fiber panel of the neutron detector and acts as the moderator for the glass fibers. Fast neutrons, x-rays and gamma rays are detected in the fast scintillator. Thermal neutrons, x-rays and gamma rays are detected in the glass fiber scintillator.

Closed Fuel Cycle Waste Treatment Strategy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vienna, J. D.; Collins, E. D.; Crum, J. V.

This study is aimed at evaluating the existing waste management approaches for nuclear fuel cycle facilities in comparison to the objectives of implementing an advanced fuel cycle in the U.S. under current legal, regulatory, and logistical constructs. The study begins with the Global Nuclear Energy Partnership (GNEP) Integrated Waste Management Strategy (IWMS) (Gombert et al. 2008) as a general strategy and associated Waste Treatment Baseline Study (WTBS) (Gombert et al. 2007). The tenets of the IWMS are equally valid to the current waste management study. However, the flowsheet details have changed significantly from those considered under GNEP. In addition, significantmore » additional waste management technology development has occurred since the GNEP waste management studies were performed. This study updates the information found in the WTBS, summarizes the results of more recent technology development efforts, and describes waste management approaches as they apply to a representative full recycle reprocessing flowsheet. Many of the waste management technologies discussed also apply to other potential flowsheets that involve reprocessing. These applications are occasionally discussed where the data are more readily available. The report summarizes the waste arising from aqueous reprocessing of a typical light-water reactor (LWR) fuel to separate actinides for use in fabricating metal sodium fast reactor (SFR) fuel and from electrochemical reprocessing of the metal SFR fuel to separate actinides for recycle back into the SFR in the form of metal fuel. The primary streams considered and the recommended waste forms include; Tritium in low-water cement in high integrity containers (HICs); Iodine-129: As a reference case, a glass composite material (GCM) formed by the encapsulation of the silver Mordenite (AgZ) getter material in a low-temperature glass is assumed. A number of alternatives with distinct advantages are also considered including a fused silica waste form with encapsulated nano-sized AgI crystals; Carbon-14 immobilized as a CaCO3 in a cement waste form; Krypton-85 stored as a compressed gas; An aqueous reprocessing high-level waste (HLW) raffinate waste immobilized by the vitrification process; An undissolved solids (UDS) fraction from aqueous reprocessing of LWR fuel either included in the borosilicate HLW glass or immobilized in the form of a metal alloy or titanate ceramics; Zirconium-based LWR fuel cladding hulls and stainless steel (SS) fuel assembly hardware super-compacted for disposal or purified for reuse (or disposal as low-level waste, LLW) of Zr by reactive gas separations; Electrochemical process salt HLW incorporated into a glass bonded Sodalite waste form; and Electrochemical process UDS and SS cladding hulls melted into an iron based alloy waste form. Mass and volume estimates for each of the recommended waste forms based on the source terms from a representative flowsheet are reported. In addition to the above listed primary waste streams, a range of secondary process wastes are generated by aqueous reprocessing of LWR fuel, metal SFR fuel fabrication, and electrochemical reprocessing of SFR fuel. These secondary wastes have been summarized and volumes estimated by type and classification. The important waste management data gaps and research needs have been summarized for each primary waste stream and selected waste process.« less

Kenaf-glass fiber reinforced unsaturated polyester hybrid composites: Tensile properties

NASA Astrophysics Data System (ADS)

Zhafer, S. F.; Rozyanty, A. R.; Shahnaz, S. B. S.; Musa, L.; Zuliahani, A.

2016-07-01

The use of natural fibers in composite is rising in recent years due their lightweight, non-abrasive, combustible, non-toxic, low cost and biodegradable properties. However, in comparison with synthetic fibers, the mechanical properties of natural fibers are lower. Therefore, the inclusion of synthetic fibers could improve the mechanical performance of natural fiber based composites. In this study, kenaf bast fiber and glass fiber at different weight percentage loading were used as reinforcement to produce hybrid composites. Unsaturated polyester (UP) resin was used as matrix and hand lay-up process was performed to apply the UP resin on the hybrid kenaf bast/glass fiber composite. Effect of different fiber loading on tensile strength, tensile modulus and elongation at break of the hybrid composite was studied. It has been found that the highest value of tensile strength and modulus was achieved at 10 wt.% kenaf/10 wt.% glass fiber loading. It was concluded that addition of glass fiber has improved the tensile properties of kenaf bast fiber based UP composites.

Elastic hysteresis phenomena in ULE and Zerodur optical glasses at elevated temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilkins, S.C.; Coon, D.N.; Epstein, J.S.

1988-01-01

Elastic hysteresis phenomena were observed in ULE and Zerodur glasses at elevated temperatures up to glass transition. These effects were found under load deformation testing using four-point bending. Permanent creep resulted in Zerodur at 900/degree/C and in ULE at 1000/degree/C. The deformation was monitored at mid-span of the samples with a capacitance-type transducer having 0.01 micrometer resolution. These hysteresis effects may be classified as elastic bimodulus between loading and unloading; that is, two different elastic moduli were observed between loading and unloading. Upon complete unloading, a minimal deformation state promptly returned, indicating little or no viscoelastic creep. The hysteresis effectmore » may be attributed to a change in glass structure as a function of stress state. A description of the test apparatus and procedure, test results for both glasses at several elevated temperatures, and an elementary discussion of continuum theory of constitutive behavior are included. 6 refs., 9 figs.« less

Enhanced 99 Tc retention in glass waste form using Tc(IV)-incorporated Fe minerals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Um, Wooyong; Luksic, Steven A.; Wang, Guohui

Technetium (99Tc) immobilization by doping into iron oxide mineral phases may alleviate the problems with Tc volatility during vitrification of nuclear waste. Reduced Tc, Tc(IV), substitutes for Fe(III) in the crystal structure by a process of Tc reduction from Tc(VII) to Tc(IV) followed by co-precipitation of Fe oxide minerals. Two Tc-incorporated Fe minerals (Tc-goethite and Tc-magnetite/maghemite) were prepared and tested for Tc retention in glass melt samples at temperatures between 600 – 1,000 oC. After being cooled, the solid glass specimens prepared at different temperatures were analyzed for Tc oxidation state using Tc K-edge XANES. In most samples, Tc wasmore » partially oxidized from Tc(IV) to Tc(VII) as the melt temperature increased. However, Tc retention in glass melt samples prepared using Tc-incorporated Fe minerals were moderately higher than in glass prepared using KTcO4 because of limited and delayed Tc volatilization.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.

This paper provides an overview of research evaluating the use of tellurite glass as a waste form for salt wastes from electrochemical processing. The capacities to immobilize different salts were evaluated including: a LiCl-Li2O oxide reduction salt (for oxide fuel) containing fission products, a LiCl-KCl eutectic salt (for metallic fuel) containing fission products, and SrCl2. Physical and chemical properties of the glasses were characterized by using X-ray diffraction, bulk density measurements, chemical durability tests, scanning electron microscopy, and energy dispersive X-ray emission spectroscopy. These glasses were found to accommodate high concentrations of halide salts and have high densities. However, improvementsmore » are needed to meet chemical durability requirements.« less

Effect of low-speed impact damage on the buckling properties of E-glass/epoxy laminates

NASA Astrophysics Data System (ADS)

Yapici, A.; Metin, M.

2009-11-01

The postimpact buck ling loads of E-glass/epoxy laminates have been measured. Composite samples with the stacking sequence [+45/-45/90/0]2s were subjected to low-speed impact loadings at various energy levels. The tests were conducted on a specially developed vertical drop-weight testing machine. The main impact parameters, such as the peak load, absorbed energy, deflection at the peak load, and damage area, were evaluated and com pared. The damaged specimens were subjected to compressive axial forces, and their buckling loads were determined. The relation between the level of impact energy and buck ling loads is investigated.

The liquidus temperature of nuclear waste glasses: an international Round-Robin Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Hrma, Pavel R.; Vienna, John D.

2012-12-01

Ten institutions from five countries participated in a Round Robin study to contribute to the Precision and Bias section of an American Society for Testing and Materials standard procedure that Pacific Northwest National Laboratory (PNNL) is developing for measuring the liquidus temperature (TL) of radioactive and simulated waste glasses. In this study, three separate TL measurement methods were a gradient temperature (GT) method, a uniform temperature (UT) method, and a crystal fraction extrapolation (CF) method. Three different glasses were measured with a combination of these three methods. The TL values reported by different institutions are generally consistent and vary withinmore » a narrow range. The precision of a TL measurement was evaluated as ±10°C regardless of the method used for making the measurement. The Round Robin glasses were all previously studied at PNNL and included ARG-1 (Glass A), Zr-9 (Glass B), and AmCm2-19 (Glass C), with measured TL values spanning the temperature range ~960-1240°C. The three methods discussed here in more detail are the GT, UT, and CF methods. A best-case precision for TL has been obtained from the data, even though the data were not acquired for all three glasses using all three methods from each participating organization.« less

FY2016 ILAW Glass Corrosion Testing with the Single-Pass Flow-Through Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neeway, James J.; Asmussen, Robert M.; Parruzot, Benjamin PG

The inventory of immobilized low-activity waste (ILAW) produced at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) will be disposed of at the near-surface, on-site Integrated Disposal Facility (IDF). When groundwater comes into contact with the waste form, the glass will corrode and radionuclides will be released into the near-field environment. Because the release of the radionuclides is dependent on the dissolution rate of the glass, it is important that the performance assessment (PA) model accounts for the dissolution rate of the glass as a function of various chemical conditions. To accomplish this, an IDF PA model based onmore » Transition State Theory (TST) can be employed. The model is able to account for changes in temperature, exposed surface area, and pH of the contacting solution as well as the effect of silicon concentrations in solution, specifically the activity of orthosilicic acid (H4SiO4), whose concentration is directly linked to the glass dissolution rate. In addition, the IDF PA model accounts for the alkali-ion exchange process as sodium is leached from the glass and into solution. The effect of temperature, pH, H4SiO4 activity, and the rate of ion-exchange can be parameterized and implemented directly into the PA rate law model. The rate law parameters are derived from laboratory tests with the single-pass flow-through (SPFT) method. To date, rate law parameters have been determined for seven ILAW glass compositions, thus additional rate law parameters on a wider range of compositions will supplement the existing body of data for PA maintenance activities. The data provided in this report can be used by ILAW glass scientists to further the understanding of ILAW glass behavior, by IDF PA modelers to use the rate law parameters in PA modeling efforts, and by Department of Energy (DOE) contractors and decision makers as they assess the IDF PA program.« less

Property/composition relationships for Hanford high-level waste glasses melting at 115{degrees}C volume 1: Chapters 1-11

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrma, P.R.; Piepel, G.F.

1994-12-01

A Composition Variation study (CVS) is being performed within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) project in support of a future high-level nuclear waste vitrification plant at the Hanford site in Washington. From 1989 to 1994, over 120 nonradioactive glasses were melted and properties measured in five statistically-designed experimental phases. Glass composition is represented by the 10 components SiO{sub 2}, B{sub 2}O{sub 3}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}, ZrO{sub 2}, Na{sub 2}O, Li{sub 2}O, CaO, MgO, and Others (all remaining components). The properties measured include viscosity ({eta}), electrical conductivity ({epsilon}), glass transition temperature (T{sub g} ), thermalmore » expansion of solid glass ({alpha}{sub s}) and molten glass ({alpha}{sub m}), crystallinity (quenched and canister centerline cooled glasses), liquidus temperature (T{sub L}), durability based on normalized elemental releases from the Materials Characterization Center-1 28-day dissolution test (MCC-1, r{sub mi}) and the 7-day Product Consistency Test (PCT, r{sub pi}), and solution pHs from MCC-1 and PCT. Amorphous phase separation was also evaluated. Empirical first- and second-order mixture models were fit using the CVS data to relate the various properties to glass composition. Equations for calculating the uncertainty associated with property values predicted by the models were also developed. The models were validated using both internal and external data. Other modeling approaches (e.g., non-bridging oxygen, free energy of hydration, phase-equilibria T{sub L}) were investigated for specific properties. A preliminary Qualified Composition Region was developed to identify glass compositions with high confidence of being processable in a melter and meeting waste form acceptance criteria.« less

FINAL REPORT INTEGRATED DM1200 MELTER TESTING USING AZ 102 AND C 106/AY-102 HLW SIMULANTS: HLW SIMULANT VERIFICATION VSL-05R5800-1 REV 0 6/27/05

DOE Office of Scientific and Technical Information (OSTI.GOV)

KRUGER AA; MATLACK KS; GONG W

2011-12-29

The principal objectives of the DM1200 melter tests were to determine the effects of feed rheology, feed solid content, and bubbler configuration on glass production rate and off-gas system performance while processing the HLW AZ-101 and C-106/AY-102 feed compositions; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components, as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and post test inspections of system components. The specific objectives (including test success criteria) of this testing, along with how each objective was met, are outlined in a table. The datamore » provided in this Final Report address the impacts of HLW melter feed rheology on melter throughput and validation of the simulated HLW melter feeds. The primary purpose of this testing is to further validate/verify the HLW melter simulants that have been used for previous melter testing and to support their continued use in developing melter and off-gas related processing information for the Project. The primary simulant property in question is rheology. Simulants and melter feeds used in all previous melter tests were produced by direct addition of chemicals; these feed tend to be less viscous than rheological the upper-bound feeds made from actual wastes. Data provided here compare melter processing for the melter feed used in all previous DM100 and DM1200 tests (nominal melter feed) with feed adjusted by the feed vendor (NOAH Technologies) to be more viscous, thereby simulating more closely the upperbounding feed produced from actual waste. This report provides results of tests that are described in the Test Plan for this work. The Test Plan is responsive to one of several test objectives covered in the WTP Test Specification for this work; consequently, only part of the scope described in the Test Specification was addressed in this particular Test Plan. For the purpose of comparison, the tests reported here were performed with AZ-102 and C-106/AY-102 HLW simulants and glass compositions that are essentially the same as those used for recent DM1200 tests. One exception was the use of an alternate, higher-waste-loading C-106/AY-102 glass composition that was used in previous DM100 tests to further evaluate the performance of the optimized bubbler configuration.« less

The Dissolution Behavior of Borosilicate Glasses in Far-From Equilibrium Conditions

DOE PAGES

Neeway, James J.; Rieke, Peter C.; Parruzot, Benjamin P.; ...

2018-02-10

An area of agreement in the waste glass corrosion community is that, at far-from-equilibrium conditions, the dissolution of borosilicate glasses used to immobilize nuclear waste is known to be a function of both temperature and pH. The aim of this work is to study the effects of temperature and pH on the dissolution rate of three model nuclear waste glasses (SON68, ISG, AFCI). The dissolution rate data are then used to parameterize a kinetic rate model based on Transition State Theory that has been developed to model glass corrosion behavior in dilute conditions. To do this, experiments were conducted atmore » temperatures of 23, 40, 70, and 90 °C and pH(22 °C) values of 9, 10, 11, and 12 with the single-pass flow-through (SPFT) test method. Both the absolute dissolution rates and the rate model parameters are compared with previous results. Rate model parameters for the three glasses studied here are nearly equivalent within error and in relative agreement with previous studies though quantifiable differences exist. The glass dissolution rates were analyzed with a linear multivariate regression (LMR) and a nonlinear multivariate regression performed with the use of the Glass Corrosion Modeling Tool (GCMT), with which a robust uncertainty analysis is performed. This robust analysis highlights the high degree of correlation of various parameters in the kinetic rate model. As more data are obtained on borosilicate glasses with varying compositions, a mathematical description of the effect of glass composition on the rate parameter values should be possible. This would allow for the possibility of calculating the forward dissolution rate of glass based solely on composition. In addition, the method of determination of parameter uncertainty and correlation provides a framework for other rate models that describe the dissolution rates of other amorphous and crystalline materials in a wide range of chemical conditions. As a result, the higher level of uncertainty analysis would provide a basis for comparison of different rate models and allow for a better means of quantifiably comparing the various models.« less

The dissolution behavior of borosilicate glasses in far-from equilibrium conditions

NASA Astrophysics Data System (ADS)

Neeway, James J.; Rieke, Peter C.; Parruzot, Benjamin P.; Ryan, Joseph V.; Asmussen, R. Matthew

2018-04-01

An area of agreement in the waste glass corrosion community is that, at far-from-equilibrium conditions, the dissolution of borosilicate glasses used to immobilize nuclear waste is known to be a function of both temperature and pH. The aim of this work is to study the effects of temperature and pH on the dissolution rate of three model nuclear waste glasses (SON68, ISG, AFCI). The dissolution rate data are then used to parameterize a kinetic rate model based on Transition State Theory that has been developed to model glass corrosion behavior in dilute conditions. To do this, experiments were conducted at temperatures of 23, 40, 70, and 90 °C and pH (22 °C) values of 9, 10, 11, and 12 with the single-pass flow-through (SPFT) test method. Both the absolute dissolution rates and the rate model parameters are compared with previous results. Rate model parameters for the three glasses studied here are nearly equivalent within error and in relative agreement with previous studies though quantifiable differences exist. The glass dissolution rates were analyzed with a linear multivariate regression (LMR) and a nonlinear multivariate regression performed with the use of the Glass Corrosion Modeling Tool (GCMT), with which a robust uncertainty analysis is performed. This robust analysis highlights the high degree of correlation of various parameters in the kinetic rate model. As more data are obtained on borosilicate glasses with varying compositions, a mathematical description of the effect of glass composition on the rate parameter values should be possible. This would allow for the possibility of calculating the forward dissolution rate of glass based solely on composition. In addition, the method of determination of parameter uncertainty and correlation provides a framework for other rate models that describe the dissolution rates of other amorphous and crystalline materials in a wide range of chemical conditions. The higher level of uncertainty analysis would provide a basis for comparison of different rate models and allow for a better means of quantifiably comparing the various models.

The Dissolution Behavior of Borosilicate Glasses in Far-From Equilibrium Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neeway, James J.; Rieke, Peter C.; Parruzot, Benjamin P.

An area of agreement in the waste glass corrosion community is that, at far-from-equilibrium conditions, the dissolution of borosilicate glasses used to immobilize nuclear waste is known to be a function of both temperature and pH. The aim of this work is to study the effects of temperature and pH on the dissolution rate of three model nuclear waste glasses (SON68, ISG, AFCI). The dissolution rate data are then used to parameterize a kinetic rate model based on Transition State Theory that has been developed to model glass corrosion behavior in dilute conditions. To do this, experiments were conducted atmore » temperatures of 23, 40, 70, and 90 °C and pH(22 °C) values of 9, 10, 11, and 12 with the single-pass flow-through (SPFT) test method. Both the absolute dissolution rates and the rate model parameters are compared with previous results. Rate model parameters for the three glasses studied here are nearly equivalent within error and in relative agreement with previous studies though quantifiable differences exist. The glass dissolution rates were analyzed with a linear multivariate regression (LMR) and a nonlinear multivariate regression performed with the use of the Glass Corrosion Modeling Tool (GCMT), with which a robust uncertainty analysis is performed. This robust analysis highlights the high degree of correlation of various parameters in the kinetic rate model. As more data are obtained on borosilicate glasses with varying compositions, a mathematical description of the effect of glass composition on the rate parameter values should be possible. This would allow for the possibility of calculating the forward dissolution rate of glass based solely on composition. In addition, the method of determination of parameter uncertainty and correlation provides a framework for other rate models that describe the dissolution rates of other amorphous and crystalline materials in a wide range of chemical conditions. As a result, the higher level of uncertainty analysis would provide a basis for comparison of different rate models and allow for a better means of quantifiably comparing the various models.« less

Common Sense Initiative’s Recommendation on Cathode Ray Tube (CRT) Glass-to-Glass

EPA Pesticide Factsheets

From 1994 through 1998, EPA’s Common Sense Initiative (CSI) Computers and Electronics Subcommittee (CES) formed a workgroup to examine regulatory barriers to pollution prevention and electronic waste recycling.

Strength Analysis of Glass-Fiber-Reinforced Plastic during Buckling,

DTIC Science & Technology

An algorithm is developed for calculating and analyzing the stress tensor by the experimental function of deflections during the buckling of glass ... fiber -reinforced plastic shells loaded with a hydrostatic load. Malmeyster’s theory of strength is used to qualitatively establish the possible points of shell failure. (Author-PL)

Comparison of the fracture resistances of glass fiber mesh- and metal mesh-reinforced maxillary complete denture under dynamic fatigue loading

PubMed Central

2017-01-01

PURPOSE The aim of this study was to investigate the effect of reinforcing materials on the fracture resistances of glass fiber mesh- and Cr–Co metal mesh-reinforced maxillary complete dentures under fatigue loading. MATERIALS AND METHODS Glass fiber mesh- and Cr–Co mesh-reinforced maxillary complete dentures were fabricated using silicone molds and acrylic resin. A control group was prepared with no reinforcement (n = 15 per group). After fatigue loading was applied using a chewing simulator, fracture resistance was measured by a universal testing machine. The fracture patterns were analyzed and the fractured surfaces were observed by scanning electron microscopy. RESULTS After cyclic loading, none of the dentures showed cracks or fractures. During fracture resistance testing, all unreinforced dentures experienced complete fracture. The mesh-reinforced dentures primarily showed posterior framework fracture. Deformation of the all-metal framework caused the metal mesh-reinforced denture to exhibit the highest fracture resistance, followed by the glass fiber mesh-reinforced denture (P<.05) and the control group (P<.05). The glass fiber mesh-reinforced denture primarily maintained its original shape with unbroken fibers. River line pattern of the control group, dimples and interdendritic fractures of the metal mesh group, and radial fracture lines of the glass fiber group were observed on the fractured surfaces. CONCLUSION The glass fiber mesh-reinforced denture exhibits a fracture resistance higher than that of the unreinforced denture, but lower than that of the metal mesh-reinforced denture because of the deformation of the metal mesh. The glass fiber mesh-reinforced denture maintains its shape even after fracture, indicating the possibility of easier repair. PMID:28243388

Integrated Disposal Facility FY 2012 Glass Testing Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Eric M.; Kerisit, Sebastien N.; Krogstad, Eirik J.

2013-03-29

PNNL is conducting work to provide the technical basis for estimating radionuclide release from the engineered portion of the disposal facility for Hanford immobilized low-activity waste (ILAW). Before the ILAW can be disposed, DOE must conduct a performance assessment (PA) for the Integrated Disposal Facility (IDF) that describes the long-term impacts of the disposal facility on public health and environmental resources. As part of the ILAW glass testing program, PNNL is implementing a strategy, consisting of experimentation and modeling, to provide the technical basis for estimating radionuclide release from the glass waste form in support of future IDF PAs. Keymore » activities in FY12 include upgrading the STOMP/eSTOMP codes to do near-field modeling, geochemical modeling of PCT tests to determine the reaction network to be used in the STOMP codes, conducting PUF tests on selected glasses to simulate and accelerate glass weathering, developing a Monte Carlo simulation tool to predict the characteristics of the weathered glass reaction layer as a function of glass composition, and characterizing glasses and soil samples exhumed from an 8-year lysimeter test. The purpose of this report is to summarize the progress made in fiscal year (FY) 2012 and the first quarter of FY 2013 toward implementing the strategy with the goal of developing an understanding of the long-term corrosion behavior of LAW glasses.« less

Recycling of waste automotive laminated glass and valorization of polyvinyl butyral through mechanochemical separation.

PubMed

Swain, Basudev; Ryang Park, Jae; Yoon Shin, Dong; Park, Kyung-Soo; Hwan Hong, Myung; Gi Lee, Chan

2015-10-01

Due to strong binding, optical clarity, adhesion to many surfaces, toughness and flexibility polyvinyl butyral (PVB) resin films are commonly used in the automotive and architectural application as a protective interlayer in the laminated glass. Worldwide million tons of PVB waste generated from end-of-life automotive associated with various environmental issues. Stringent environmental directive, higher land cost eliminates land filling option, needs a study, we have developed a mechanochemical separation process to separate PVB resins from glass and characterized the separated PVB through various techniques, i.e., scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), infrared spectroscopy (IR) and nuclear magnetic resonance spectroscopy (NMR). Commercial nonionic surfactants D201 used for the mechanochemical separation purpose. Through parameter optimization following conditions are considered to be the optimum condition; 30v ol% D201, stirring speed of 400 rpm, 35 °C temperature, operation time 1h, and dilute D201 volume to waste automotive laminated glass weight ratio of ≈25. The technology developed in our laboratory is sustainable, environmentally friendly, techno-economical feasible process, capable of mass production (recycling). Copyright © 2015 Elsevier Inc. All rights reserved.

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... include, but is not limited to, elements such as segregation and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation...

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... include, but is not limited to, elements such as segregation and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation...

Initial retrieval sequence and blending strategy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pemwell, D.L.; Grenard, C.E.

1996-09-01

This report documents the initial retrieval sequence and the methodology used to select it. Waste retrieval, storage, pretreatment and vitrification were modeled for candidate single-shell tank retrieval sequences. Performance of the sequences was measured by a set of metrics (for example,high-level waste glass volume, relative risk and schedule).Computer models were used to evaluate estimated glass volumes,process rates, retrieval dates, and blending strategy effects.The models were based on estimates of component inventories and concentrations, sludge wash factors and timing, retrieval annex limitations, etc.

Exploring high-strength glass-ceramic materials for upcycling of industrial wastes

NASA Astrophysics Data System (ADS)

Back, Gu-Seul; Park, Hyun Seo; Seo, Sung Mo; Jung, Woo-Gwang

2015-11-01

To promote the recycling of industrial waste and to develop value-added products using these resources, the possibility of manufacturing glass-ceramic materials of SiO2-CaO-Al2O3 system has been investigated by various heat treatment processes. Glass-ceramic materials with six different chemical compositions were prepared using steel industry slags and power plant waste by melting, casting and heat treatment. The X-ray diffraction results indicated that diopside and anorthite were the primary phases in the samples. The anorthite phase was formed in SiO2-rich material (at least 43 wt%). In CaO-rich material, the gehlenite phase was formed. By the differential scanning calorimetry analyses, it was found that the glass transition point was in the range of 973-1023 K, and the crystallization temperature was in the range of 1123-1223 K. The crystallization temperature increased as the content of Fe2O3 decreased. By the multi-step heat treatment process, the formation of the anorthite phase was enhanced. Using FactSage, the ratio of various phases was calculated as a function of temperature. The viscosities and the latent heats for the samples with various compositions were also calculated by FactSage. The optimal compositions for glass-ceramics materials were discussed in terms of their compressive strength, and micro-hardness.

SME Acceptability Determination For DWPF Process Control (U)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, T.

2017-06-12

The statistical system described in this document is called the Product Composition Control System (PCCS). K. G. Brown and R. L. Postles were the originators and developers of this system as well as the authors of the first three versions of this technical basis document for PCCS. PCCS has guided acceptability decisions for the processing at the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) since the start of radioactive operations in 1996. The author of this revision to the document gratefully acknowledges the firm technical foundation that Brown and Postles established to support the ongoing successfulmore » operation at the DWPF. Their integration of the glass propertycomposition models, developed under the direction of C. M. Jantzen, into a coherent and robust control system, has served the DWPF well over the last 20+ years, even as new challenges, such as the introduction into the DWPF flowsheet of auxiliary streams from the Actinide Removal Process (ARP) and other processes, were met. The purpose of this revision is to provide a technical basis for modifications to PCCS required to support the introduction of waste streams from the Salt Waste Processing Facility (SWPF) into the DWPF flowsheet. An expanded glass composition region is anticipated by the introduction of waste streams from SWPF, and property-composition studies of that glass region have been conducted. Jantzen, once again, directed the development of glass property-composition models applicable for this expanded composition region. The author gratefully acknowledges the technical contributions of C.M. Jantzen leading to the development of these glass property-composition models. The integration of these models into the PCCS constraints necessary to administer future acceptability decisions for the processing at DWPF is provided by this sixth revision of this document.« less

Conducting glasses recovered from thin film transistor liquid crystal display wastes for dye-sensitized solar cell cathodes.

PubMed

Chen, C-C; Chang, F-C; Peng, C Y; Wang, H Paul

2015-01-01

Transparent conductive glasses such as thin film transistor (TFT) array and colour filter glasses were recovered from the TFT-liquid crystal display panel wastes by dismantling and sonic cleaning. Noble metals (i.e. platinum (Pt)) and indium tin oxide (ITO) are generally used in the cathode of a dye-sensitized solar cell (DSSC). To reduce the DSSC cost, Pt was replaced with nano nickel-encapsulated carbon-shell (Ni@C) nanoparticles, which were prepared by carbonization of Ni²⁺-β-cyclodextrin at 673 K for 2 h. The recovered conductive glasses were used in the DSSC electrodes in the substitution of relatively expensive ITO. Interestingly, the efficiency of the DSSC having the Ni@C-coated cathode is as high as 2.54%. Moreover, the cost of the DSSC using the recovered materials can be reduced by at least 24%.

Fluorescent Lamp Glass Waste Incorporation into Clay Ceramic: A Perfect Solution

NASA Astrophysics Data System (ADS)

Morais, Alline Sardinha Cordeiro; Vieira, Carlos Maurício Fontes; Rodriguez, Rubén Jesus Sanchez; Monteiro, Sergio Neves; Candido, Veronica Scarpini; Ferreira, Carlos Luiz

2016-09-01

The mandatory use of fluorescent lamps as part of a Brazilian energy-saving program generates a huge number of spent fluorescent lamps (SFLs). After operational life, SFLs cannot be disposed as common garbage owing to mercury and lead contamination. Recycling methods separate contaminated glass tubes and promote cleaning for reuse. In this work, glass from decontaminated SFLs was incorporated into clay ceramics, not only as an environmental solution for such glass wastes and clay mining reduction but also due to technical and economical advantages. Up to 30 wt.% of incorporation, a significant improvement in fired ceramic flexural strength and a decrease in water absorption was observed. A prospective analysis showed clay ceramic incorporation as an environmentally correct and technical alternative for recycling the enormous amount of SFLs disposed of in Brazil. This could also be a solution for other world clay ceramic producers, such as US, China and some European countries.

Improvement in hardness of soda-lime-silica glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakraborty, Riya; De, Moumita; Roy, Sudakshina

2012-06-05

Hardness is a key design parameter for structural application of brittle solids like glass. Here we report for the first time the significant improvement of about 10% in Vicker's hardness of a soda-lime-silica glass with loading rate in the range of 0.1-10 N.s{sup -1}. Corroborative dark field optical and scanning electron microscopy provided clue to this improvement through evidence of variations in spatial density of shear deformation band formation as a function of loading rate.

The oxidative stability of carbon fibre reinforced glass-matrix composites

NASA Technical Reports Server (NTRS)

Prewo, K. M.; Batt, J. A.

1988-01-01

The environmental stability of carbon fibre reinforced glass-matrix composites is assessed. Loss of composite strength due to oxidative exposure at elevated temperatures under no load, static load and cyclic fatigue as well as due to thermal cycling are all examined. It is determined that strength loss is gradual and predictable based on the oxidation of carbon fibres. The glass matrix was not found to prevent this degradation but simply to limit it to a gradual process progressing from the composite surfaces inward.

Lead extraction from Cathode Ray Tube (CRT) funnel glass: Reaction mechanisms in thermal reduction with addition of carbon (C).

PubMed

Lu, Xingwen; Ning, Xun-An; Chen, Da; Chuang, Kui-Hao; Shih, Kaimin; Wang, Fei

2018-06-01

This study quantitatively determined the extraction of lead from CRT funnel glass and examined the mechanisms of thermally reducing lead in the products of sintering Pb-glass with carbon in the pre-heated furnace. The experimentally derived results indicate that a 90.3 wt% lead extraction efficiency can be achieved with 20 wt% of C addition at 950 °C for 3 min under air. The formation of viscous semi-liquid glass blocked the oxygen supply between the interaction of C and Pb-glass, and was highly effective for the extraction of metallic Pb. A maximum of 87.3% lead recover was obtained with a C to Na 2 CO 3 ratio of 1/3 at 1200 °C. The decrease of C/Na 2 CO 3 ratio enhanced the metallic lead recovery by increasing the glass viscosity for effective sedimentation of metallic lead in the bottom. However, with the further increase of temperature and treatment time, re-vitrification of lead back to silicate-glass matrix was detected in both Pb-glass/C and Pb-glass/C/Na 2 CO 3 systems. The findings indicated that with proper controls, using C as an inexpensive reagent can effectively reduce treatment time and energy, which is crucial to a waste-to-resource technology for economically recovering lead from the waste CRT glass. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hanford Low-Activity Waste Processing: Demonstration of the Off-Gas Recycle Flowsheet - 13443

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramsey, William G.; Esparza, Brian P.

2013-07-01

Vitrification of Hanford Low-Activity Waste (LAW) is nominally the thermal conversion and incorporation of sodium salts and radionuclides into borosilicate glass. One key radionuclide present in LAW is technetium-99. Technetium-99 is a low energy, long-lived beta emitting radionuclide present in the waste feed in concentrations on the order of 1-10 ppm. The long half-life combined with a high solubility in groundwater results in technetium-99 having considerable impact on performance modeling (as potential release to the environment) of both the waste glass and associated secondary waste products. The current Hanford Tank Waste Treatment and Immobilization Plant (WTP) process flowsheet calls formore » the recycle of vitrification process off-gas condensates to maximize the portion of technetium ultimately immobilized in the waste glass. This is required as technetium acts as a semi-volatile specie, i.e. considerable loss of the radionuclide to the process off-gas stream can occur during the vitrification process. To test the process flowsheet assumptions, a prototypic off-gas system with recycle capability was added to a laboratory melter (on the order of 1/200 scale) and testing performed. Key test goals included determination of the process mass balance for technetium, a non-radioactive surrogate (rhenium), and other soluble species (sulfate, halides, etc.) which are concentrated by recycling off-gas condensates. The studies performed are the initial demonstrations of process recycle for this type of liquid-fed melter system. This paper describes the process recycle system, the waste feeds processed, and experimental results. Comparisons between data gathered using process recycle and previous single pass melter testing as well as mathematical modeling simulations are also provided. (authors)« less

Development of a sintering process for recycling oil shale fly ash and municipal solid waste incineration bottom ash into glass ceramic composite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Zhikun; Zhang, Lei; Li, Aimin, E-mail: leeam@dlut.edu.cn

Highlights: • Glass ceramic composite is prepared from oil shale fly ash and MSWI bottom ash. • A novel method for the production of glass ceramic composite is presented. • It provides simple route and lower energy consumption in terms of recycling waste. • The vitrified slag can promote the sintering densification process of glass ceramic. • The performances of products decrease with the increase of oil shale fly ash content. - Abstract: Oil shale fly ash and municipal solid waste incineration bottom ash are industrial and municipal by-products that require further treatment before disposal to avoid polluting the environment.more » In the study, they were mixed and vitrified into the slag by the melt-quench process. The obtained vitrified slag was then mixed with various percentages of oil shale fly ash and converted into glass ceramic composites by the subsequent sintering process. Differential thermal analysis was used to study the thermal characteristics and determine the sintering temperatures. X-ray diffraction analysis was used to analyze the crystalline phase compositions. Sintering shrinkage, weight loss on ignition, density and compressive strength were tested to determine the optimum preparation condition and study the co-sintering mechanism of vitrified amorphous slag and oil shale fly ash. The results showed the product performances increased with the increase of sintering temperatures and the proportion of vitrified slag to oil shale fly ash. Glass ceramic composite (vitrified slag content of 80%, oil shale fly ash content of 20%, sintering temperature of 1000 °C and sintering time of 2 h) showed the properties of density of 1.92 ± 0.05 g/cm{sup 3}, weight loss on ignition of 6.14 ± 0.18%, sintering shrinkage of 22.06 ± 0.6% and compressive strength of 67 ± 14 MPa. The results indicated that it was a comparable waste-based material compared to previous researches. In particular, the energy consumption in the production process was reduced compared to conventional vitrification and sintering method. Chemical resistance and heavy metals leaching results of glass ceramic composites further confirmed the possibility of its engineering applications.« less

Borofloat and Starphire Float Glasses: A Comparison

DOE PAGES

Wereszczak, Andrew A.; Anderson Jr., Charles E.

2014-10-28

Borofloat ® borosilicate float glass and Starphire ® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shockmore » differences, and internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.« less

Secondary Waste Cast Stone Waste Form Qualification Testing Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westsik, Joseph H.; Serne, R. Jeffrey

2012-09-26

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). Cast Stone – a cementitious waste form, has been selected for solidification of this secondary waste stream after treatment in the ETF. The secondary-waste Cast Stone waste form must be acceptablemore » for disposal in the IDF. This secondary waste Cast Stone waste form qualification testing plan outlines the testing of the waste form and immobilization process to demonstrate that the Cast Stone waste form can comply with the disposal requirements. Specifications for the secondary-waste Cast Stone waste form have not been established. For this testing plan, Cast Stone specifications are derived from specifications for the immobilized LAW glass in the WTP contract, the waste acceptance criteria for the IDF, and the waste acceptance criteria in the IDF Permit issued by the State of Washington. This testing plan outlines the testing needed to demonstrate that the waste form can comply with these waste form specifications and acceptance criteria. The testing program must also demonstrate that the immobilization process can be controlled to consistently provide an acceptable waste form product. This testing plan also outlines the testing needed to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support performance assessment analyses of the long-term environmental impact of the secondary-waste Cast Stone waste form in the IDF« less

Recycling Today Makes for a Better Tomorrow.

ERIC Educational Resources Information Center

Raze, Robert E., Jr.

1992-01-01

Today's children must be educated about solid waste management and recycling to reduce the amount of waste that goes into landfills. The article describes what can be recycled (newspapers, corrugated cardboard, paper, glass, aluminum, textiles, motor oil, organic wastes, appliances, steel cans, and plastics). It also lists student environment…

LEATHER TANNERY WASTE MANAGEMENT THROUGH PROCESS CHANGE, REUSE AND PRETREATMENT

EPA Science Inventory

Reduction of tannery waste, i.e., trivalent chromium, sulfide and oil and grease components has been accomplished by process change. Protein recovery and hydroclonic separation of solids was shown to be possible in tannery processing in reducing waste loading. All waste load redu...

Immobilization of LiCl-Li 2 O pyroprocessing salt wastes in chlorosodalite using glass-bonded hydrothermal and salt-occlusion methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riley, Brian J.; Peterson, Jacob A.; Kroll, Jared O.

In this study, salt occlusion and hydrothermal processes were used to make chlorosodalite through reaction with a high-LiCl salt simulating a waste stream following pyrochemical treatment of oxide-based used nuclear fuel. Some products were reacted with glass binders to increase chlorosodalite yield through alkali ion exchange and aide in densification. Hydrothermal processes included reaction of the salt simulant in an acid digestion vessel with either zeolite 4A or sodium aluminate and colloidal silica. Chlorosodalite yields in the crystalline products were nearly complete in the glass-bonded materials at values of 100 mass% for the salt-occlusion method, up to 99.0 mass% formore » the hydrothermal synthesis with zeolite 4A, and up to 96 mass% for the hydrothermal synthesis with sodium aluminate and colloidal silica. These results show promise for using chemically stable chlorosodalite to immobilize oxide reduction salt wastes.« less

Durability of waste glass flax fiber reinforced mortar

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aly, M.; Hashmi, M. S. J.; Olabi, A. G.

2011-01-17

The main concern for natural fibre reinforced mortar composites is the durability of the fibres in the alkaline environment of cement. The composites may undergo a reduction in strength as a result of weakening of the fibres by a combination of alkali attack and fibre mineralisation. In order to enhance the durability of natural fiber reinforced cement composites several approaches have been studied including fiber impregnation, sealing of the matrix pore system and reduction of matrix alkalinity through the use of pozzolanic materials. In this study waste glass powder was used as a pozzolanic additive to improve the durability performancemore » of flax fiber reinforced mortar (FFRM). The durability of the FFRM was studied by determining the effects of ageing in water and exposure to wetting and drying cycles; on the microstructures and flexural behaviour of the composites. The mortar tests demonstrated that the waste glass powder has significant effect on improving the durability of FFRM.« less

X-ray micro-tomography investigation of the foaming process in the system of waste glass–silica mud–MnO{sub 2}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ducman, V., E-mail: vilma.ducman@zag.si; Korat, L.; Legat, A.

2013-12-15

In case of foamed lightweight aggregates (LWAs), porosity is introduced by the addition of a foaming agent to the glassy matrix, which degasses at an elevated temperature, so that the resulting gases remain trapped inside the glassy structure. The efficiency of action of MnO{sub 2} as a foaming agent in waste glass and waste glass/silica mud systems was studied. Samples were fired at different temperatures and with different dwelling times at a certain temperature, and the development of porosity was investigated by means of X-ray micro-tomography. It was found that, with the prolongation in dwelling times, the number of poresmore » decreased, while, on the other hand, the volume of these pores increased, and that the addition of silica mud increases the foaming temperature and slows down the foaming process. - Highlights: • Preparation of lightweight aggregate from waste glass, silica sludge, and MnO{sub 2} • DTA/TG investigation of MnO{sub 2} • Characterization of pore-forming process by means of X-ray micro-tomography (μcT)« less

Recycling of indium from waste LCD: A promising non-crushing leaching with the aid of ultrasonic wave.

PubMed

Zhang, Kaihua; Li, Bin; Wu, Yufeng; Wang, Wei; Li, Rubing; Zhang, Yi-Nan; Zuo, Tieyong

2017-06-01

The tremendous amount of end-of-life liquid crystal displays (LCDs) has become one of the prominent sources of waste electrical and electronic equipment (WEEE) in recent years. Despite the necessity of safe treatment, recycling indium is also a focus of waste LCD treatment because of the scarcity of indium. Based on the analyses of the structure of Indium Tin Oxide (ITO) glass, crushing is demonstrated to be not required. In the present research, a complete non-crushing leaching method was firstly adopted to recycle indium from waste LCDs, and the ultrasonic waves was applied in the leaching process. The results demonstrated that indium can be leached efficiently with even a low concentration of chloride acid (HCl) without extra heating. About 96.80% can be recovered in 60mins, when the ITO glass was leached by 0.8MHCl with an enhancement of 300W ultrasonic waves. The indium leaching process is abridged free from crushing, and proves to be of higher efficiency. In addition, the ultrasonic wave influence on leaching process was also explained combing with micron-scale structure of ITO glass. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental Assessment: Disposition of Chiefs’ Circle Residential Structures

DTIC Science & Technology

2012-04-27

the restrooms and kitchen when being used by the CFC and Scouts, respectively. Final - Environmental Assessment...Solid waste (not hazardous waste) associated with the Proposed Action Site includes waste such as kitchen waste, paper, plastics, metal and glass...specific soil groups (hydraquents and udor- thents), and four urban land complexes. The acreage covered by each soil type and its percentage of the

MEASUREMENT OF WASTE LOADING IN SALTSTONE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harbour, J; Vickie Williams, V

2008-07-18

One of the goals of the Saltstone variability study is to identify the operational and compositional variables that control or influence the important processing and performance properties of Saltstone grout mixtures. One of those properties of importance is the Waste Loading (WL) of the decontaminated salt solution (DSS) in the Saltstone waste form. Waste loading is a measure of the amount of waste that can be incorporated within a waste form. The value of the Saltstone waste loading ultimately determines the number of vaults that will be required to disposition all of the DSS. In this report, the waste loadingmore » is defined as the volume in milliliters of DSS per liter of Saltstone waste form. The two most important parameters that determine waste loading for Saltstone are water to cementitious material (w/cm) ratio and the cured grout density. Data are provided that show the dependence of waste loading on the w/cm ratio for a fixed DSS composition using the current premix material (45% Blast Furnace Slag (BFS), 45% Fly Ash (FA) and 10% Ordinary Portland Cement (OPC)). The impact of cured grout density on waste loading was also demonstrated. Mixes (at 0.60 w/cm) made with a Modular Caustic side extraction Unit (MCU) simulant and either OPC or BFS have higher cured grout densities than mixes made with premix and increase the WL to 709 mL/L for the OPC mix and 689 mL/L for the BFS mix versus the value of 653 mL/L for MCU in premix at 0.60 w/cm ratio. Bleed liquid reduces the waste loading and lowers the effective w/cm ratio of Saltstone. A method is presented (and will be used in future tasks) for correcting the waste loading and the w/cm ratio of the as-batched mixes in those cases where bleed liquid is present. For example, the Deliquification, Dissolution and Adjustment (DDA) mix at an as-batched 0.60 w/cm ratio, when corrected for % bleed, gives a mix with a 0.55 w/cm ratio and a WL that has been reduced from 662 to 625 mL/L. An example is provided that demonstrated the quantitative impact of WL on the number of cells (each Saltstone vault contains two cells) required to disposition all of the {approx}100 million gallons of DSS available in the tanks. This calculation revealed that the number of cells required over the range of 0.48 to 0.62 w/cm ratio (equivalent to a WL range of 591 to 666 mL/L) varies from 65 to 57 cells (33 to 29 vaults). The intent of this oversimplified example was to show the range of variation in vaults expected due to w/cm ratio rather than to estimate the actual number of vaults required. There is a tradeoff between the waste loading and the processing and performance properties of Saltstone. The performance properties improve in general as the w/cm ratio decreases whereas the waste loading is reduced at lower w/cm ratios resulting in a larger number of Saltstone vaults. The final performance and processing requirements of Saltstone will determine the maximum waste loading achievable.« less

High solids co-digestion of food and landscape waste and the potential for ammonia toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drennan, Margaret F.; DiStefano, Thomas D., E-mail: thomas.distefano@bucknell.edu

Highlights: • We evaluated co-digestion of food and landscape waste with a pilot-scale anaerobic dry digester. • We evaluated reactor performance at 35 °C under low and high organic loading rates. • Performance was stable under low organic loading rate, but declined under high organic loading rate. • Respirometry was employed to investigate potential inhibition due to ammonia. • Landscape waste was unsuitable in increasing the C:N ratio during codigestion. - Abstract: A pilot-scale study was completed to determine the feasibility of high-solids anaerobic digestion (HSAD) of a mixture of food and landscape wastes at a university in central Pennsylvaniamore » (USA). HSAD was stable at low loadings (2 g COD/L-day), but developed inhibitory ammonia concentrations at high loadings (15 g COD/L-day). At low loadings, methane yields were 232 L CH{sub 4}/kg COD fed and 229 L CH{sub 4}/kg VS fed, and at high loadings yields were 211 L CH{sub 4}/kg COD fed and 272 L CH{sub 4}/kg VS fed. Based on characterization and biodegradability studies, food waste appears to be a good candidate for HSAD at low organic loading rates; however, the development of ammonia inhibition at high loading rates suggests that the C:N ratio is too low for use as a single substrate. The relatively low biodegradability of landscape waste as reported herein made it an unsuitable substrate to increase the C:N ratio. Codigestion of food waste with a substrate high in bioavailable carbon is recommended to increase the C:N ratio sufficiently to allow HSAD at loading rates of 15 g COD/L-day.« less

IMPACTS OF ANTIFOAM ADDITIONS AND ARGON BUBBLING ON DEFENSE WASTE PROCESSING FACILITY REDUCTION/OXIDATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, C.; Johnson, F.

2012-06-05

During melting of HLW glass, the REDOX of the melt pool cannot be measured. Therefore, the Fe{sup +2}/{Sigma}Fe ratio in the glass poured from the melter must be related to melter feed organic and oxidant concentrations to ensure production of a high quality glass without impacting production rate (e.g., foaming) or melter life (e.g., metal formation and accumulation). A production facility such as the Defense Waste Processing Facility (DWPF) cannot wait until the melt or waste glass has been made to assess its acceptability, since by then no further changes to the glass composition and acceptability are possible. therefore, themore » acceptability decision is made on the upstream process, rather than on the downstream melt or glass product. That is, it is based on 'feed foward' statistical process control (SPC) rather than statistical quality control (SQC). In SPC, the feed composition to the melter is controlled prior to vitrification. Use of the DWPF REDOX model has controlled the balanjce of feed reductants and oxidants in the Sludge Receipt and Adjustment Tank (SRAT). Once the alkali/alkaline earth salts (both reduced and oxidized) are formed during reflux in the SRAT, the REDOX can only change if (1) additional reductants or oxidants are added to the SRAT, the Slurry Mix Evaporator (SME), or the Melter Feed Tank (MFT) or (2) if the melt pool is bubble dwith an oxidizing gas or sparging gas that imposes a different REDOX target than the chemical balance set during reflux in the SRAT.« less

An investigation of waste glass-based geopolymers supplemented with alumina

NASA Astrophysics Data System (ADS)

Christiansen, Mary U.

An increased consideration of sustainability throughout society has resulted in a surge of research investigating sustainable alternatives to existing construction materials. A new binder system, called a geopolymer, is being investigated to supplement ordinary portland cement (OPC) concrete, which has come under scrutiny because of the CO2 emissions inherent in its production. Geopolymers are produced from the alkali activation of a powdered aluminosilicate source by an alkaline solution, which results in a dense three-dimensional matrix of tetrahedrally linked aluminosilicates. Geopolymers have shown great potential as a building construction material, offering similar mechanical and durability properties to OPC. Additionally, geopolymers have the added value of a considerably smaller carbon footprint than OPC. This research considered the compressive strength, microstructure and composition of geopolymers made from two types of waste glass with varying aluminum contents. Waste glass shows great potential for mainstream use in geopolymers due to its chemical and physical homogeneity as well as its high content of amorphous silica, which could eliminate the need for sodium silicate. However, the lack of aluminum is thought to negatively affect the mechanical performance and alkali stability of the geopolymer system. 39 Mortars were designed using various combinations of glass and metakaolin or fly ash to supplement the aluminum in the system. Mortar made from the high-Al glass (12% Al2O3) reached over 10,000 psi at six months. Mortar made from the low-Al glass (<1% Al2O3) did not perform as well and remained sticky even after several weeks of curing, most likely due to the lack of Al which is believed to cause hardening in geopolymers. A moderate metakaolin replacement (25-38% by mass) was found to positively affect the compressive strength of mortars made with either type of glass. Though the microstructure of the mortar was quite indicative of mechanical performance, composition was also found to be important. The initial stoichiometry of the bulk mixture was maintained fairly closely, especially in mixtures made with fine glass. This research has shown that glass has great potential for use in geopolymers, when care is given to consider the compositional and physical properties of the glass in mixture design.

Balance of oxygen throughout the conversion of a high-level waste melter feed to glass

DOE PAGES

Lee, SeungMin; Hrma, Pavel; Kloužek, Jaroslav; ...

2017-07-03

Gases evolve from nuclear waste melter feed during conversion to glass in response to heating. This article is focused on oxygen mass balance based on the stoichiometry of feed melting reactions and evolved-gas analysis data. Whereas O 2-producing and -consuming batch-melting reactions are complete in the reacting and primary-foam layers of the cold cap, O 2 from redox reactions continues to evolve as long as melt temperature increases, and thus generates secondary foam. Also, we discuss the relationship between the oxygen mass balance and the temperature-dependent iron redox ratio and the O 2 partial pressure, as they evolve during themore » feed-to-glass conversion.« less

Balance of oxygen throughout the conversion of a high-level waste melter feed to glass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, SeungMin; Hrma, Pavel; Kloužek, Jaroslav

Gases evolve from nuclear waste melter feed during conversion to glass in response to heating. This article is focused on oxygen mass balance based on the stoichiometry of feed melting reactions and evolved-gas analysis data. Whereas O 2-producing and -consuming batch-melting reactions are complete in the reacting and primary-foam layers of the cold cap, O 2 from redox reactions continues to evolve as long as melt temperature increases, and thus generates secondary foam. Also, we discuss the relationship between the oxygen mass balance and the temperature-dependent iron redox ratio and the O 2 partial pressure, as they evolve during themore » feed-to-glass conversion.« less

Glasphalt test sections in Virginia.

DOT National Transportation Integrated Search

1997-01-01

There is an effort to utilize waste materials in construction processes to diminish the amount placed in landfills. Mixed-color glass, which is not recyclable in the glass industry, has been used in asphalt, but there have been reservations about the...

Fixation of the stressed state of glass plates by coating them with thin films using a plasma focus installation

NASA Astrophysics Data System (ADS)

Kolokoltsev, V. N.; Degtiarev, V. F.; Borovitskaya, I. V.; Nikulin, V. Ya.; Peregudova, E. N.; Silin, P. V.; Eriskin, A. A.

2018-01-01

Elastic deformation in transparent mediums is usually studied by the photoelasticity method. For opaque mediums the method of film coating and strain gauge method are used. After the external load was removed, the interference pattern corresponding to elastic deformation of the material disappears. It is found that the elastic deformation state of the thin glass plate under the action of concentrated load can be fixed during the deposition of a thin metal film. Deposition of thin copper films was carried out by passing of plasma through the copper tube installed inside the Plasma Focus installation. After removing of the load, interference pattern on the glass plates was observed in the form of Newton’s rings and isogers in non-monochromatic light on the CCD scanners which uses uorescent lamps with cold cathode. It is supposed that the copper film fixes the relief of the surface of the glass plate at the time of deformation and saves it when the load is removed. In the case of a concentrated load, this relief has the shape of a thin lens of large radius. For this reason, the interference of coherent light rays in a thin air gap between the glass of the scanners atbed and the lens surface has the shape of Newton's rings. In this case, when scanning the back side of the plate, isogyres are observed. The presented method can be used in the analysis of the mechanical stress in a various optical elements.

Industrial waste utilization in the panels production for high buildings facade and socle facing

NASA Astrophysics Data System (ADS)

Vitkalova, Irina; Torlova, Anastasiya; Pikalov, Evgeniy; Selivanov, Oleg

2018-03-01

The research presents comprehensive utilization of such industrial waste as galvanic sludge, broken window glass as functional additives for producing ceramics for facade and socle paneling in high-rise construction. The basic charge component is low-plasticity clay, which does not allow producing high-quality products if used without any functional additives. The application of the mentioned above components broadens the resource base, reduces production cost and the mass of the products in comparison with the currently used facing ceramics. The decrease of product mass helps to reduce the load on the basement and to use ceramic material in high-rise construction more effectively. Additional advantage of the developed composition is the reducing of production energy intensity due to comparatively low pressing pressure and firing temperature thus reducing the overall production cost. The research demonstrates the experimental results of determining density, compressive strength, water absorption, porosity and frost resistance of the produced ceramic material. These characteristics prove that the material can be applied for high buildings outdoor paneling. Additional research results prove ecologic safety of the produced ceramic material.

Effect of binder burnout on the sealing performance of glass ceramics for solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Ertugrul, Tugrul Y.; Celik, Selahattin; Mat, Mahmut D.

2013-11-01

The glass ceramics composite sealants are among few materials suitable for the solid oxide fuel cells (SOFC) due to their high operating temperatures (600 °C-850 °C). The glass ceramics chemically bond to both the metallic interconnector and the ceramic electrolyte and provide a gas tight connection. A careful and several stages manufacturing procedure is required to obtain a gas tight sealing. In this study, effects of binder burnout process on the sealing performance are investigated employing commercially available glass ceramic powders. The glass ceramic laminates are produced by mixing glass ceramic powders with the organic binders and employing a tape casting method. The laminates are sandwiched between the metallic interconnectors of an SOFC cell. The burnout and subsequent sealing quality are analyzed by measuring leakage rate and final macrostructure of sealing region. The effects of heating rate, dead weight load, solid loading, carrier gas and their flow rates are investigated. It is found that sealing quality is affected from all investigated parameters. While a slower heating rate is required for a better burnout, the mass flow rate of sweep gas must be adequate for removal of the burned gas. The leakage rate is reduced to 0.1 ml min-1 with 2 °C min-1 + 1 °C min-1 heating rate, 86.25% solid loading, 200 N dead weight load and 500 ml min-1 sweep gas flow rate.

40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection of... (CRTs) and Processed CRT Glass Undergoing Recycling. Used, broken CRTs are not solid wastes if they meet... destined for recycling and if they meet the following requirements: (1) Storage. The broken CRTs must be...

40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection of... (CRTs) and Processed CRT Glass Undergoing Recycling. Used, broken CRTs are not solid wastes if they meet... destined for recycling and if they meet the following requirements: (1) Storage. The broken CRTs must be...

40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection of... (CRTs) and Processed CRT Glass Undergoing Recycling. Used, broken CRTs are not solid wastes if they meet... destined for recycling and if they meet the following requirements: (1) Storage. The broken CRTs must be...

40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

Code of Federal Regulations, 2011 CFR

2011-07-01

... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection of... (CRTs) and Processed CRT Glass Undergoing Recycling. Used, broken CRTs are not solid wastes if they meet... destined for recycling and if they meet the following requirements: (1) Storage. The broken CRTs must be...

40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection of... (CRTs) and Processed CRT Glass Undergoing Recycling. Used, broken CRTs are not solid wastes if they meet... destined for recycling and if they meet the following requirements: (1) Storage. The broken CRTs must be...

Nepheline structural and chemical dependence on melt composition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcial, José; Crum, Jarrod; Neill, Owen

Nepheline crystallizes upon slow-cooling in some melts concentrated in Na2O and Al2O3, which can result in a residual glass phase of low chemical durability. Nepheline can incorporate many components often found in high-level waste radioactive borosilicate glass, including glass network ions (e.g., Si, Al, Fe), alkali metals (e.g., Cs, K, Na, and possibly Li), alkaline-earth metals (e.g., Ba, Sr, Ca, Mg), and transition metals (e.g., Mn, and possibly Cr, Zn, Ni). When crystallized from melts of different compositions, nepheline chemistry varies as a function of starting glass composition. Five simulated high level nuclear waste borosilicate glasses shown to crystallize largemore » fractions of nepheline on slow cooling, were selected for study. These melts constituted a range of Al2O3, B2O3, CaO, Na2O, K2O, Fe2O3, and SiO2 compositions. Compositional analyses of nepheline crystals in glass by electron probe micro-analysis (EPMA) indicate that boron is unlikely to be present in any significant concentration, if at all, in nepheline. Also, several models are presented for calculating the fraction of vacancies in the nepheline structure.« less

Bisphenol A in Solid Waste Materials, Leachate Water, and Air Particles from Norwegian Waste-Handling Facilities: Presence and Partitioning Behavior.

PubMed

Morin, Nicolas; Arp, Hans Peter H; Hale, Sarah E

2015-07-07

The plastic additive bisphenol A (BPA) is commonly found in landfill leachate at levels exceeding acute toxicity benchmarks. To gain insight into the mechanisms controlling BPA emissions from waste and waste-handling facilities, a comprehensive field and laboratory campaign was conducted to quantify BPA in solid waste materials (glass, combustibles, vehicle fluff, waste electric and electronic equipment (WEEE), plastics, fly ash, bottom ash, and digestate), leachate water, and atmospheric dust from Norwegian sorting, incineration, and landfill facilities. Solid waste concentrations varied from below 0.002 mg/kg (fly ash) to 188 ± 125 mg/kg (plastics). A novel passive sampling method was developed to, for the first time, establish a set of waste-water partition coefficients, KD,waste, for BPA, and to quantify differences between total and freely dissolved concentrations in waste-facility leachate. Log-normalized KD,waste (L/kg) values were similar for all solid waste materials (from 2.4 to 3.1), excluding glass and metals, indicating BPA is readily leachable. Leachate concentrations were similar for landfills and WEEE/vehicle sorting facilities (from 0.7 to 200 μg/L) and dominated by the freely dissolved fraction, not bound to (plastic) colloids (agreeing with measured KD,waste values). Dust concentrations ranged from 2.3 to 50.7 mg/kgdust. Incineration appears to be an effective way to reduce BPA concentrations in solid waste, dust, and leachate.

40 CFR 426.111 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... glass furnace or furnaces. (c) The term “oil” shall mean those components of a waste water amenable to... analysis of grease in polluted waters, waste waters, and effluents, such as “Standard Methods,” 13th...

40 CFR 426.121 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... glass furnace or furnaces. (c) The term “oil” shall mean those components of a waste water amenable to... analysis of grease in polluted waters, waste waters, and effluents, such as “Standard Methods,” 13th...

40 CFR 426.111 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... glass furnace or furnaces. (c) The term “oil” shall mean those components of a waste water amenable to... analysis of grease in polluted waters, waste waters, and effluents, such as “Standard Methods,” 13th...

40 CFR 426.121 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... glass furnace or furnaces. (c) The term “oil” shall mean those components of a waste water amenable to... analysis of grease in polluted waters, waste waters, and effluents, such as “Standard Methods,” 13th...

Glass-ceramics from municipal incinerator fly ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boccaccini, A.R.; Petitmermet, M.; Wintermantel, E.

1997-11-01

In countries where the population density is high and the availability of space for landfilling is limited, such as the west-European countries and Japan, the significance of municipal solid waste incineration, as part of the waste management strategy, is continuously increasing. In Germany and Switzerland, for example, more than {approximately}40% of unrecycled waste is being or will be incinerated. Also, in other countries, including the US, the importance of waste incineration will increase in the next few years. Although incineration reduces the volume of the waste by {approximately} 90%, it leaves considerable amounts of solid residues, such as bottom andmore » boiler ashes, and filter fly ashes. Consequently, new technological options for the decontamination and/or inertization of incinerator filter fly ash are being developed with the objective of rendering a product that can be reused or, at least, be deposited in standard landfill sites with no risk. The proposed alternatives include immobilization by cement-based techniques, wet chemical treatments and thermal treatments of vitrification. Of these, vitrification is the most promising solution, because, if residues are melted at temperatures > 1,300 C, a relatively inert glass is produced. In the present investigation, glass-ceramics were obtained by a controlled crystallization heat treatment of vitrified incinerator filter fly ashes. The mechanical and other technical properties of the products were measured with special emphasis on assessing their in vitro toxic potential.« less

A Strategy to Conduct an Analysis of the Long-Term Performance of Low-Activity Waste Glass in a Shallow Subsurface Disposal System at Hanford

DOE Office of Scientific and Technical Information (OSTI.GOV)

BP McGrail, WL Ebert, DH Bacon, DM Strachan

1998-02-18

Privatized services are being procured to vitrify low-activity tank wastes for eventual disposal in a shallow subsurface facility at the Hanford Site. Over 500,000 metric tons of low-activity waste glass will be generated, which is among the largest volumes of waste within the U.S. Department of Energy (DOE) complex and is one of the largest inventories of long-lived radionuclides planned for disposal in a low-level waste facility. Before immobilized waste can be disposed, DOE must approve a "performance assessment," which is a document that describes the impacts of the disposal facility on public health and environmental resources. Because the releasemore » rate of radionuclides from the glass waste form is a key factor determining these impacts, a sound scientific basis for determining their long-term release rates must be developed if this disposal action is to be accepted by regulatory agencies, stakeholders, and the public. In part, the scientific basis is determined from a sound testing strategy. The foundation of the proposed testing strategy is a well accepted mechanistic model that is being used to calculate the glass corrosion behavior over the geologic time scales required for performance assessment. This model requires that six parameters be determined, and the testing program is defined by an appropriate set of laboratory experiments to determine these parameters, and is combined with a set of field experiments to validate the model as a whole. Three general classes of laboratory tests are proposed in this strategy: 1) characterization, 2) accelerated, and 3) service condition. Characterization tests isolate and provide specific information about processes or parameters in theoretical models. Accelerated tests investigate corrosion behavior that will be important over the regulated service life of a disposal system within a laboratory time frame of a few years or less. Service condition tests verify that the techniques used in accelerated tests do not change the alteration mechanisms. The recommended characterization tests are single-pass flow-through tests using a batch reactor design, Accelerated and service conditions tests include product consistency and pressurized unsaturated flow (PUF) tests. Nonradioactive glasses will be used for the majority of the laboratory testing (-80%), with the remainder performed with glasses containing a selected set of key radionuclides. Additionally, a series of PUF experiments with a natural analog of basaltic glass is recommended to confirm that the alteration products observed under accelerated conditions in the PUF tests are similar to those found associated with the natural analog. This will provide additional confidence in using the PUF test results to infer long-term corrosion behavior. Field tests are proposed as a unique way to validate the glass corrosion and contaminant transport models being used in the performance assessment. To better control the test conditions, the field tests are to be performed in lysimeters (corrugated steel containers buried flush with the ground surface). Lysimeters provide a way to combine a glass, Hanford soil, and perhaps other engineered materials in a well-controlled test, but on a scale that is not practicable in the laboratory. The recommended field tests include some experiments where a steady flow rate of water is artificially applied. These tests use a glass designed to have a high corrosion rate so that it is easier to monitor contaminant release and transport. Existing lysimeters at the Hanford Site can be used for these experiments or new lysimeters that have been equipped with the latest in monitoring equipment and located near the proposed disposal site.« less

Anaerobic co-digestion of food waste and dairy manure: effects of food waste particle size and organic loading rate.

PubMed

Agyeman, Fred O; Tao, Wendong

2014-01-15

This study was to comprehensively evaluate the effects of food waste particle size on co-digestion of food waste and dairy manure at organic loading rates increased stepwise from 0.67 to 3 g/L/d of volatile solids (VS). Three anaerobic digesters were fed semi-continuously with equal VS amounts of food waste and dairy manure. Food waste was ground to 2.5 mm (fine), 4 mm (medium), and 8 mm (coarse) for the three digesters, respectively. Methane production rate and specific methane yield were significantly higher in the digester with fine food waste. Digestate dewaterability was improved significantly by reducing food waste particle size. Specific methane yield was highest at the organic loading rate of 2g VS/L/d, being 0.63, 0.56, and 0.47 L CH4/g VS with fine, medium, and coarse food waste, respectively. Methane production rate was highest (1.40-1.53 L CH4/L/d) at the organic loading rate of 3 g VS/L/d. The energy used to grind food waste was minor compared with the heating value of the methane produced. Copyright © 2013 Elsevier Ltd. All rights reserved.

Air pollution control residues from waste incineration: current UK situation and assessment of alternative technologies.

PubMed

Rani, D Amutha; Boccaccini, A R; Deegan, D; Cheeseman, C R

2008-11-01

Current disposal options for APC residues in the UK and alternative treatment technologies developed world-wide have been reviewed. APC residues are currently landfilled in the UK where they undergo in situ solidification, although the future acceptability of this option is uncertain because the EU waste acceptance criteria (WAC) introduce strict limits on leaching that are difficult to achieve. Other APC residue treatment processes have been developed which are reported to reduce leaching to below relevant regulatory limits. The Ferrox process, the VKI process, the WES-PHix process, stabilisation/solidification using cementitious binders and a range of thermal treatment processes are reviewed. Thermal treatment technologies convert APC residues combined with other wastes into inert glass or glass-ceramics that encapsulate heavy metals. The waste management industry will inevitably use the cheapest available option for treating APC residues and strict interpretation and enforcement of waste legislation is required if new, potentially more sustainable technologies are to become commercially viable.

Effect of water temperature on cyclic fatigue properties of glass-fiber-reinforced hybrid composite resin and its fracture pattern after flexural testing.

PubMed

Kuroda, Soichi; Shinya, Akikazu; Vallittu, Pekka K; Nakasone, Yuji; Shinya, Akiyoshi

2013-02-01

To evaluate in vitro the influence of dynamic loading applied to a glass-fiber-reinforced hybrid composite resin on its flexural strength in a moist, simulated oral environment. Three-point flexural strength specimens were subjected to cyclic loading in water at 37°C and 55°C to investigate the influence of immersion temperature on impact fatigue properties. Specimens were subjected to cyclic impact loading at 1 Hz for up to 5 × 105 cycles to obtain the number of cycles to failure, the number of unbroken specimens after 5 × 105 cycles, and the residual flexural strength of unbroken specimens. Maximum loads of 100, 200, and 300 N were chosen for both the non-reinforced and the glass-fiber reinforced hybrid composite resins. The mean residual flexural strength for 100 N impact loading at temperatures of 37°C and 55°C was 634 and 636 MPa, respectively. All specimens fractured at fewer than 5 × 105 cycles for loads of 200 and 300 N. Reduced numbers of cycles to fracture and lower fatigue values were observed as both the maximum load and immersion temperature increased.

Fatigue of graphite/epoxy buffer strip panels with center cracks

NASA Technical Reports Server (NTRS)

Bigelow, C. A.

1985-01-01

The effects of fatigue loading on the behavior of graphite/epoxy panels with either S-Glass or Kevlar-49 buffer strips is studied. Buffer strip panels are fatigued and tested in tension to measure their residual strength with crack-like damage. Panels are made with 45/0/-45/90 sub 2s layup with either S-Glass or Kevlar-49 buffer strip material. The buffer strips are parallel to the loading direction and made by replacing narrow strips of the 0-degree graphite plies with strips of either 0-degree S-Glass/epoxy or Kevlar-49/epoxy on a one-for-one basis. The panels are subjected to a fatigue loading spectrum MINITWIST, the shortened version of the standardized load program for the wing lower surface of a transport aircraft. Two levels of maximum strain are used in the spectrum with three durations of the fatigue spectrum. One group of panels is preloaded prior to the application of the fatigue cycling. The preload consists of statistically loading the spectrum in tension until the crack-tip damage zone reaches the ajacent buffer strips. After fatigue loading, all specimens are statistically loaded in tension to failure to determine their residual strengths.

40 CFR 60.2630 - What should I include in my waste management plan?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What should I include in my waste management plan? 60.2630 Section 60.2630 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... consideration of the reduction or separation of waste-stream elements such as paper, cardboard, plastics, glass...

40 CFR 62.14590 - What should I include in my waste management plan?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 9 2014-07-01 2014-07-01 false What should I include in my waste management plan? 62.14590 Section 62.14590 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... separation of waste-stream elements such as paper, cardboard, plastics, glass, batteries, or metals; or the...

40 CFR 62.14590 - What should I include in my waste management plan?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 9 2013-07-01 2013-07-01 false What should I include in my waste management plan? 62.14590 Section 62.14590 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... separation of waste-stream elements such as paper, cardboard, plastics, glass, batteries, or metals; or the...

40 CFR 60.2065 - What should I include in my waste management plan?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What should I include in my waste management plan? 60.2065 Section 60.2065 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... reduction or separation of waste-stream elements such as paper, cardboard, plastics, glass, batteries, or...

40 CFR 60.2901 - What should I include in my waste management plan?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What should I include in my waste management plan? 60.2901 Section 60.2901 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... consideration of the reduction or separation of waste-stream elements such as paper, cardboard, plastics, glass...

40 CFR 60.2065 - What should I include in my waste management plan?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What should I include in my waste management plan? 60.2065 Section 60.2065 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... reduction or separation of waste-stream elements such as paper, cardboard, plastics, glass, batteries, or...