Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

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

Langton, C. A.; Stefanko, D. B.

2013-04-23

Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: 1) physically stabilize the final landfill by filling the empty volume in the tanks with a non-compressible material; 2) provide a barrier for inadvertent intrusion into the tank; 3) reduce contaminant mobility by a) limiting the hydraulic conductivity of the closed tank and b) reducing contact between the residual waste and infiltrating water; and 4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify amore » single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: 1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). 2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. 3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix

TANKS 18 AND 19-F STRUCTURAL FLOWABLE GROUT FILL MATERIAL EVALUATION AND RECOMMENDATIONS

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

Stefanko, D.; Langton, C.

2011-11-01

Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: (1) physically stabilize the final landfill by filling the empty volume in the tanks with a non compressible material; (2) provide a barrier for inadvertent intrusion into the tank; (3) reduce contaminant mobility by (a) limiting the hydraulic conductivity of the closed tank and (b) reducing contact between the residual waste and infiltrating water; and (4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identifymore » a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: (1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). (2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. (3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable

TANK 18-F AND 19-F TANK FILL GROUT SCALE UP TEST SUMMARY

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

Stefanko, D.; Langton, C.

2012-01-03

High-level waste (HLW) tanks 18-F and 19-F have been isolated from FTF facilities. To complete operational closure the tanks will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) entombing waste removal equipment, (4) discouraging future intrusion, and (5) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. This report documents the results of a four cubic yard bulk fill scale up test on the grout formulation recommended for filling Tanks 18-F and 19-F. Details of the scale upmore » test are provided in a Test Plan. The work was authorized under a Technical Task Request (TTR), HLE-TTR-2011-008, and was performed according to Task Technical and Quality Assurance Plan (TTQAP), SRNL-RP-2011-00587. The bulk fill scale up test described in this report was intended to demonstrate proportioning, mixing, and transportation, of material produced in a full scale ready mix concrete batch plant. In addition, the material produced for the scale up test was characterized with respect to fresh properties, thermal properties, and compressive strength as a function of curing time.« less

Effects of Coal Gangue on Cement Grouting Material Properties

NASA Astrophysics Data System (ADS)

Liu, J. Y.; Chen, H. X.

2018-05-01

The coal gangue is one of the most abundant industrial solid wastes and pollute source of air and water. The use of coal gangue in the production of cement grouting material comforms to the basic state policy of environment protection and the circular using of natural resources. Through coal gangue processing experiment, coal gangue cement grouting materials making test, properties detection of properties and theoretical analysis, the paper studied the effects of coal gangue on the properties of cement grouting materials. It is found that at the range of 600 to 700 °C, the fluidity and the compressive and flexural strengths of the cement grouting materials increase with the rising up of the calcination temperatures of coal gangue. The optimum calcination temperature is around 700 °C. The part substitution of cement by the calcined coal gangue in the cement grouting material will improve the mechanical properties of the cement grouting material, even thought it will decrease its fluidity. The best substitution amount of cement by coal gangue is about 30%. The fluidity and the long term strength of the ordinary silicate cement grouting material is obviously higher than that of the sulphoaluminate cement one as well as that of the silicate-sulphoaluminate complex cement one.

Antenna grout replacement system

NASA Technical Reports Server (NTRS)

Mcclung, C. E. (Inventor)

1983-01-01

An epoxy grout suitable for use in mounting and positioning bearing runner plates used in hydrostatic bearing assemblies for rotatably mounting large radio telescope structures to stationary support pedestals is described. The epoxy grout may be used in original mountings or may be used as part of a replacement system for repairing cavities in existing grout resulting from grout deterioration. The epoxy grout has a relatively short work life and cure time even in the presence of hydraulic oil. The epoxy grout cures without shrinking or sagging to form a grout which is sufficiently strong and durable to provide a grout especially well suited for use under the high pressure loading and close tolerance requirements of large hydrostatic bearing assemblies.

Negative grouting consequences on karst environment

NASA Astrophysics Data System (ADS)

Bonacci, O.; Roje-Bonacci, T.; Gottstein, S.

2009-04-01

Grouting is a procedure by means of which grout is injected into different kinds of karst spaces (cracks, fissures, conduits and caves). It has a wide application in modern civil engineering, especially in karst terrains. It started nearly 200 years ago. In most cases the ingredients for the preparation of mortars and grouting suspensions are: cement, bentonite, clay and fillers, additives for stability and water. In practice the composition of grouting suspension is not standardized. A suspension injected under pressure will circulate in the karst spaces like a more or less viscous fluid until some of the larger suspended particles are blocked where the karst voids get narrower than the size of injected grains. The injection of materials into karst groundwater, i.e. the construction of grouting curtains, definitely could be the cause of unpredictable negative consequences on karst groundwater environments. The building of dams in karst areas always go along the construction of grouting curtains. During the construction of most dams in karst all over the world millions tons of injection mass have been injected in karst underground. It may impact water quantity in vadose zone and in karstic aquifer causing water table lowering and spring desiccation. In such cases the negative impact on local karst environment could be very dangerous. Physically as well as chemically this mass voraciously and quickly destroyed underground habitats and killed an enormous number of endangered and endemic species. Very often this is extremely expensive procedure and in many cases not very successful from the engineering point of view. From the ecological point of view it could causes catastrophic consequences. The greatest problem is that until now neither engineers nor ecologists took care of these great and massive negative influences on underground karst environments. In this paper few examples of different consequences of grouting on the hydrogeological as well as ecological regime

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

Rheological Characteristics of Cement Grout and its Effect on Mechanical Properties of a Rock Fracture

NASA Astrophysics Data System (ADS)

Liu, Quansheng; Lei, Guangfeng; Peng, Xingxin; Lu, Chaobo; Wei, Lai

2018-02-01

Grouting reinforcement, which has an obvious strengthening effect on fractured rock mass, has been widely used in various fields in geotechnical engineering. The rheological properties of grout will greatly affect its diffusion radius in rock fractures, and the water-cement ratio is an important factor in determining the grouting flow patterns. The relationship between shear stress and shear rate which could reflect the grout rheological properties, the effects of water-cement ratio, and temperature on the rheological properties of grouting was studied in the laboratory. Besides, a new method for producing fractured rock specimens was proposed and solved the problem of producing natural fractured rock specimens. To investigate the influences of grouting on mechanical properties of a rock fracture, the fractured rock specimens made using the new method were reinforced by grouting on the independent designed grouting platform, and then normal and tangential mechanical tests were carried out on fractured rock specimens. The results showed that the mechanical properties of fractured rock mass are significantly improved by grouting, the peak shear strength and residual strength of rock fractures are greatly improved, and the resistance to deformation is enhanced after grouting. Normal forces affect the tangential behavior of the rock fracture, and the tangential stress strength increases with normal forces. The strength and stability of fractured rock mass are increased by grouting reinforcement.

Epoxy Grout With Silica Thickener

NASA Technical Reports Server (NTRS)

Mcclung, C. E.

1984-01-01

Grout cures quickly, even in presence of hydraulic oil. Grout is mixture of aggregate particles, finely-divided silica, epoxy resin, and triethylenetetramine curing agent, with mixture containing about 85 percent silica and aggregate particle sand 15 percent resin and curing agent. Silica is thickening agent and keeps grout from sagging.

Method for constructing a lined underground cavity by underreaming, grouting, and boring through the grouting

DOEpatents

Johnson, W.H.

1971-02-02

A method is described for constructing a lined underground cavity. The process includes the steps of securing a casing in a borehole by grouting, underreaming the casing, filling the underreamed region with additional grouting, and then drilling through and underreaming the added grouting, thereby forming a room having a lining formed of the grouting. By using a structurally strong grouting that is impervious to water, the resulting room is waterproof and is suitable for on-site storage of an atomic device and its associated equipment prior to an underground atomic event. Such cavities also have other uses; for example, the cavities may be made very deep and used for storage of various fluids such as natural gas storage. (5 claims)

Ultrafine cementitious grout

DOEpatents

Ahrens, Ernst H.

1999-01-01

An ultrafine cementitious grout in three particle grades containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 30 wt. % to about 70 wt. % Portland cement; from about 30 wt. % to about 70 wt. % pumice containing at least 70% amorphous silicon dioxide; and from 1.2 wt. % to about 5.0 wt. % superplasticizer. The superplasticizer is dispersed in the mixing water prior to the addition of dry grout and the W/CM ratio is about 0.4 to 1/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 .mu.m in width.

Improved method and composition for immobilization of waste in cement-based material

DOEpatents

Tallent, O.K.; Dodson, K.E.; McDaniel, E.W.

1987-10-01

A composition and method for fixation or immobilization of aqueous hazardous waste material in cement-based materials (grout) is disclosed. The amount of drainable water in the cured grout is reduced by the addition of an ionic aluminum compound to either the waste material or the mixture of waste material and dry-solid cement- based material. This reduction in drainable water in the cured grout obviates the need for large, expensive amounts of gelling clays in grout materials and also results in improved consistency and properties of these cement-based waste disposal materials.

Preparation of grout for stabilization of abandoned in-situ oil shale retorts

DOEpatents

Mallon, Richard G.

1982-01-01

A process for the preparation of grout from burned shale by treating the burned shale in steam at approximately 700.degree. C. to maximize the production of the materials alite and larnite. Oil shale removed to the surface during the preparation of an in-situ retort is first retorted on the surface and then the carbon is burned off, leaving burned shale. The burned shale is treated in steam at approximately 700.degree. C. for about 70 minutes. The treated shale is then ground and mixed with water to produce a grout which is pumped into an abandoned, processed in-situ retort, flowing into the void spaces and then bonding up to form a rigid, solidified mass which prevents surface subsidence and leaching of the spent shale by ground water.

A new design concept of fully grouted rock bolts in underground construction

NASA Astrophysics Data System (ADS)

Phich Nguyen, Quang; Nguyen, Van Manh; Tuong Nguyen, Ke

2018-04-01

The main problem after excavating an underground excavation is to maintain the stability of the excavation for a certain period of time. Failure in meeting this demand is a threat to safety of men and equipment. Support and reinforcement are different instruments with different mechanisms. Among the common support systems in tunnelling and mining, rock bolts have been widely used to reinforce rock mass and also to reduce geological hazards. Furthermore rock bolts can be applied under varying different geological conditions with cost-effectiveness. Although different methods are developed for grouted rock bolts design until now, the interaction mechanism of the rock bolts and rock mass is still very complicated issue. The paper addresses an analytical model for the analysis and design of fully grouted rock bolts based on the reinforcement principle. According to this concept the jointed rock mass reinforced by grouted rock bolts is considered as composite material which includes rock mass, the grout material and the bolt shank. The mechanical properties of this composite material depend on the ratio of the components. The closed-form solution was developed based on the assumption that the rock mass arround a circular tunnel remained elastic after installing fully grouted rock bolts. The main parameters of the rock-bolt system (the diameter and length of bolt shank, the space between the bolts) are then easily estimated from the obtained solution.

Long-Term Mechanical Behavior of Nano Silica Sol Grouting

PubMed Central

Zhang, Nong; Zhang, Chenghao; Qian, Deyu; Han, Changliang; Yang, Sen

2018-01-01

The longevity of grouting has a significant effect on the safe and sustainable operation of many engineering projects. A 500-day experiment was carried out to study the long-term mechanical behavior of nano silica sol grouting. The nano silica sol was activated with different proportions of a NaCl catalyst and cured under fluctuating temperature and humidity conditions. The mechanical parameters of the grout samples were tested using an electrohydraulic uniaxial compression tester and an improved Vicat instrument. Scanning electron microscope, X-ray diffraction, and ultrasonic velocity tests were carried out to analyze the strength change micro-mechanism. Tests showed that as the catalyst dosage in the grout mix is decreased, the curves on the graphs showing changes in the weight and geometric parameters of the samples over time could be divided into three stages, a shrinkage stage, a stable stage, and a second shrinkage stage. The catalyst improved the stability of the samples and reduced moisture loss. Temperature rise was also a driving force for moisture loss. Uniaxial compressive stress-strain curves for all of the samples were elastoplastic. The curves for uniaxial compression strength and secant modulus plotted against time could be divided into three stages. Sample brittleness increased with time and the brittleness index increased with higher catalyst dosages in the latter part of the curing time. Plastic strength-time curves exhibit allometric scaling. Curing conditions mainly affect the compactness, and then affect the strength. PMID:29337897

Ultrafine cementitious grout

DOEpatents

Ahrens, Ernst H.

1998-01-01

An ultrafine cementitious grout having a particle size 90% of which are less than 6 .mu.m in diameter and an average size of about 2.5 .mu.m or less, and preferably 90% of which are less than 5 .mu.m in diameter and an average size of about 2 .mu.m or less containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 40 wt. % to about 50 wt. % Portland cement; from about 50 wt. % to about 60 wt. % pumice containing at least 60% amorphous silicon dioxide; and from 0.1 wt. % to about 1.5 wt. % superplasticizer. The grout is mixed with water in the W/CM ratio of about 0.4-0.6/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 .mu.m in width.

Ultrafine cementitious grout

DOEpatents

Ahrens, E.H.

1998-07-07

An ultrafine cementitious grout is described having a particle size 90% of which are less than 6 {micro}m in diameter and an average size of about 2.5 {micro}m or less, and preferably 90% of which are less than 5 {micro}m in diameter and an average size of about 2 {micro}m or less containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 40 wt. % to about 50 wt. % Portland cement; from about 50 wt. % to about 60 wt. % pumice containing at least 60% amorphous silicon dioxide; and from 0.1 wt. % to about 1.5 wt. % superplasticizer. The grout is mixed with water in the W/CM ratio of about 0.4--0.6/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 {micro}m in width. 4 figs.

Direct cementitious waste option study report

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

Dafoe, R.E.; Losinski, S.J.

A settlement agreement between the Department of Energy (DOE) and the State of Idaho mandates that all high-level radioactive waste (HLW) now stored at the Idaho Chemical Processing Plant (ICPP) will be treated so that it is ready to be moved out of Idaho for disposal by a target data of 2035. This study investigates the direct grouting of all ICPP calcine (including the HLW dry calcine and those resulting from calcining sodium-bearing liquid waste currently residing in the ICPP storage tanks) as the treatment method to comply with the settlement agreement. This method involves grouting the calcined waste andmore » casting the resulting hydroceramic grout into stainless steel canisters. These canisters will be stored at the Idaho National Engineering and Environmental Laboratory (INEEL) until they are sent to a national geologic repository. The operating period for grouting treatment will be from 2013 through 2032, and all the HLW will be treated and in interim storage by the end of 2032.« less

Thermally conductive cementitious grout for geothermal heat pump systems

DOEpatents

Allan, Marita

2001-01-01

A thermally conductive cement-sand grout for use with a geothermal heat pump system. The cement sand grout contains cement, silica sand, a superplasticizer, water and optionally bentonite. The present invention also includes a method of filling boreholes used for geothermal heat pump systems with the thermally conductive cement-sand grout. The cement-sand grout has improved thermal conductivity over neat cement and bentonite grouts, which allows shallower bore holes to be used to provide an equivalent heat transfer capacity. In addition, the cement-sand grouts of the present invention also provide improved bond strengths and decreased permeabilities. The cement-sand grouts can also contain blast furnace slag, fly ash, a thermoplastic air entraining agent, latex, a shrinkage reducing admixture, calcium oxide and combinations thereof.

WASTE STABILIZATION FUNDAMENTALS FOR BIOREACTOR LANDFILLS

EPA Science Inventory

Waste stabilization is the process where putrescible waste is biodegraded by microorganisms resulting in an end-product being a relatively inert substrate (e.g., like compost). When exposed to moisture, biologically stabilized waste should not produce substantial quantitie...

Preparation of grout for stabilization of abandoned in-situ oil shale retorts. [Patent application

DOEpatents

Mallon, R.G.

1979-12-07

A process is described for the preparation of grout from burned shale by treating the burned shale in steam at approximately 700/sup 0/C to maximize the production of the materials alite and larnite. Oil shale removed to the surface during the preparation of an in-situ retort is first retorted on the surface and then the carbon is burned off, leaving burned shale. The burned shale is treated in steam at approximately 700/sup 0/C for about 70 minutes. The treated shale is then ground and mixed with water to produce a grout which is pumped into an abandoned, processed in-situ retort, flowing into the void spaces and then bonding up to form a rigid, solidified mass which prevents surface subsidence and leaching of the spent shale by ground water.

Research in Foundation Grouting with Cement

DTIC Science & Technology

1960-03-01

grout is mixed. 2. For cracks of the order of 0.05 in., a grout in which the ratio[ of water to cement is 0.75 by volune gives the r’ost desirable 4... thickness of the order of t5 in. 4. 3hear tests on grout films fog-cured at 70 F for 28 days denon- stratel that increasing the pressure within the...alkaline water dripre.I through cracks in the concrete lidng of some of the penstock tunnels Jai daaged the paint an- metal -work. The uplift pressure

Micaceous Soil Strength And Permeability Improvement Induced By Microbacteria From Vegetable Waste

NASA Astrophysics Data System (ADS)

Omar, R. C.; Roslan, R.; Baharuddin, I. N. Z.; Hanafiah, M. I. M.

2016-11-01

Green technology method using vegetable waste are introduced in this paper for improvement of phyllite residual soil from UNITEN, Campus. Residual soil from phyllite are known as micaceous soils and it give problem in managing the stability of the slope especially in wet and extensively dry seasons. Micaceous soil are collected using tube sampler technique and mixed with liquid contain microorganism from fermented vegetable waste name as vege-grout to form remolded sample. The remolded sample are classify as 15.0%, 17.5%, 20.00% and 22.5% based on different incremental percentages of vege-grout. The curing time for the sample are 7, 14, 21, 28, and 35 days before the tests were conducted. Observation of the effect of treatment shows 20.0% of liquid contain Bacillus pasteurii and Bacillus Subtilis with 21 days curing time is the optimum value in strengthening the soil and improve the permeability.

Laboratory Testing of Silica Sol Grout in Coal Measure Mudstones

PubMed Central

Pan, Dongjiang; Zhang, Nong; Xie, Zhengzheng; Feng, Xiaowei; Kong, Yong

2016-01-01

The effectiveness of silica sol grout on mudstones is reported in this paper. Using X-ray diffraction (XRD), the study investigates how the silica sol grout modifies mudstone mineralogy. Micropore sizes and mechanical properties of the mudstone before and after grouting with four different materials were determined with a surface area/porosity analyser and by uniaxial compression. Tests show that, after grouting, up to 50% of the mesopore volumes can be filled with grout, the dominant pore diameter decreases from 100 nm to 10 nm, and the sealing capacity is increased. Uniaxial compression tests of silica sol grouted samples shows that their elastic modulus is 21%–38% and their uniaxial compressive strength is 16%–54% of the non-grouted samples. Peak strain, however, is greater by 150%–270%. After grouting, the sample failure mode changes from brittle to ductile. This paper provides an experimental test of anti-seepage and strengthening properties of silica sol. PMID:28774061

Laboratory Testing of Silica Sol Grout in Coal Measure Mudstones.

PubMed

Pan, Dongjiang; Zhang, Nong; Xie, Zhengzheng; Feng, Xiaowei; Kong, Yong

2016-11-22

The effectiveness of silica sol grout on mudstones is reported in this paper. Using X-ray diffraction (XRD), the study investigates how the silica sol grout modifies mudstone mineralogy. Micropore sizes and mechanical properties of the mudstone before and after grouting with four different materials were determined with a surface area/porosity analyser and by uniaxial compression. Tests show that, after grouting, up to 50% of the mesopore volumes can be filled with grout, the dominant pore diameter decreases from 100 nm to 10 nm, and the sealing capacity is increased. Uniaxial compression tests of silica sol grouted samples shows that their elastic modulus is 21%-38% and their uniaxial compressive strength is 16%-54% of the non-grouted samples. Peak strain, however, is greater by 150%-270%. After grouting, the sample failure mode changes from brittle to ductile. This paper provides an experimental test of anti-seepage and strengthening properties of silica sol.

Effluent Management Facility Evaporator Bottom-Waste Streams Formulation and Waste Form Qualification Testing

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

Saslow, Sarah A.; Um, Wooyong; Russell, Renee L.

This report describes the results from grout formulation and cementitious waste form qualification testing performed by Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions, LLC (WRPS). These results are part of a screening test that investigates three grout formulations proposed for wide-range treatment of different waste stream compositions expected for the Hanford Effluent Management Facility (EMF) evaporator bottom waste. This work supports the technical development need for alternative disposition paths for the EMF evaporator bottom wastes and future direct feed low-activity waste (DFLAW) operations at the Hanford Site. High-priority activities included simulant production, grout formulation, and cementitious wastemore » form qualification testing. The work contained within this report relates to waste form development and testing, and does not directly support the 2017 Integrated Disposal Facility (IDF) performance assessment (PA). However, this work contains valuable information for use in PA maintenance past FY 2017 and future waste form development efforts. The provided results and data should be used by (1) cementitious waste form scientists to further the understanding of cementitious leach behavior of contaminants of concern (COCs), (2) decision makers interested in off-site waste form disposal, and (3) the U.S. Department of Energy, their Hanford Site contractors and stakeholders as they assess the IDF PA program at the Hanford Site. The results reported help fill existing data gaps, support final selection of a cementitious waste form for the EMF evaporator bottom waste, and improve the technical defensibility of long-term waste form risk estimates.« less

Experimental Characterization of Stress- and Strain-Dependent Stiffness in Grouted Rock Masses.

PubMed

Kim, Ji-Won; Chong, Song-Hun; Cho, Gye-Chun

2018-03-29

Grouting of fractured rock mass prior to excavation results in grout-filled discontinuities that govern the deformation characteristics of a site. The influence of joint characteristics on the properties of grouted rocks is important in assessing the effects of grouting on jointed rock mass. However, grouting remains a predominantly empirical practice and the effects of grouting on rock joint behavior and material properties have yet to be accurately assessed. Granular materials, including jointed rocks, typically display nonlinear strain-dependent responses that can be characterized by the shear modulus degradation curve. In this study, the effects of grouting on the strain-dependent shear stiffness of jointed rock mass were investigated at the small-strain (below 10 -5 ) and mid-strain (10 -5 to 10 -3 ) ranges using the quasi-static resonant column test and rock mass dynamic test devices. The effects of curing time, axial stress, initial joint roughness, and grouted joint thickness were examined. The results show that (1) grouting of rock joints leads to decreased stress sensitivity and increased small-strain shear stiffness for all tested samples; (2) the grouted rock samples display similar modulus degradation characteristics as the applied grout material; (3) the initial joint roughness determines the stress-dependent behaviors and general stiffness range of the jointed and grouted rocks, but the strain-dependent behaviors are dependent on the properties of the grout material; (4) increased grouted joint thickness results in larger contribution of the grout properties in the overall grouted rock mass.

Experimental Characterization of Stress- and Strain-Dependent Stiffness in Grouted Rock Masses

PubMed Central

Cho, Gye-Chun

2018-01-01

Grouting of fractured rock mass prior to excavation results in grout-filled discontinuities that govern the deformation characteristics of a site. The influence of joint characteristics on the properties of grouted rocks is important in assessing the effects of grouting on jointed rock mass. However, grouting remains a predominantly empirical practice and the effects of grouting on rock joint behavior and material properties have yet to be accurately assessed. Granular materials, including jointed rocks, typically display nonlinear strain-dependent responses that can be characterized by the shear modulus degradation curve. In this study, the effects of grouting on the strain-dependent shear stiffness of jointed rock mass were investigated at the small-strain (below 10−5) and mid-strain (10−5 to 10−3) ranges using the quasi-static resonant column test and rock mass dynamic test devices. The effects of curing time, axial stress, initial joint roughness, and grouted joint thickness were examined. The results show that (1) grouting of rock joints leads to decreased stress sensitivity and increased small-strain shear stiffness for all tested samples; (2) the grouted rock samples display similar modulus degradation characteristics as the applied grout material; (3) the initial joint roughness determines the stress-dependent behaviors and general stiffness range of the jointed and grouted rocks, but the strain-dependent behaviors are dependent on the properties of the grout material; (4) increased grouted joint thickness results in larger contribution of the grout properties in the overall grouted rock mass. PMID:29596371

BLENDED CALCIUM ALUMINATE-CALCIUM SULFATE CEMENT-BASED GROUT FOR P-REACTOR VESSEL IN-SITU DECOMMISSIONING

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

Langton, C.; Stefanko, D.

2011-03-10

The objective of this report is to document laboratory testing of blended calcium aluminate - calcium hemihydrate grouts for P-Reactor vessel in-situ decommissioning. Blended calcium aluminate - calcium hemihydrate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout which has a pH greater than 12.4. In addition, blended calcium aluminate - calcium hemihydrate cement compositions can be formulated such that the primary cementitious phase is a stable crystalline material. A less alkaline material (pH {<=} 10.5) was desired to address a potential materials compatibilitymore » issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts [Wiersma, 2009a and b, Wiersma, 2010, and Serrato and Langton, 2010]. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere [Griffin, 2010, Stefanko, 2009 and Wiersma, 2009 and 2010, Bobbitt, 2010, respectively]. Radiolysis calculations are also provided in a separate document [Reyes-Jimenez, 2010].« less

The differences between soil grouting with cement slurry and cement-water glass slurry

NASA Astrophysics Data System (ADS)

Zhu, Mingting; Sui, Haitong; Yang, Honglu

2018-01-01

Cement slurry and cement-water glass slurry are the most widely applied for soil grouting reinforcement project. The viscosity change of cement slurry is negligible during grouting period and presumed to be time-independent while the viscosity of cement-water glass slurry increases with time quickly and is presumed to be time-dependent. Due to the significantly rheology differences between them, the grouting quality and the increasing characteristics of grouting parameters may be different, such as grouting pressure, grouting surrounding rock pressure, i.e., the change of surrounding rock pressure deduced by grouting pressure. Those are main factors for grouting design. In this paper, a large-scale 3D grouting simulation device was developed to simulate the surrounding curtain grouting for a tunnel. Two series of surrounding curtain grouting experiments under different geo-stress of 100 kPa, 150 kPa and 200 kPa were performed. The overload test on tunnel was performed to evaluate grouting effect of all surrounding curtain grouting experiments. In the present results, before 240 seconds, the grouting pressure increases slowly for both slurries; after 240 seconds the increase rate of grouting pressure for cement-water glass slurry increases quickly while that for cement slurry remains roughly constant. The increasing trend of grouting pressure for cement-water glass is similar to its viscosity. The setting time of cement-water glass slurry obtained from laboratory test is less than that in practical grouting where grout slurry solidifies in soil. The grouting effect of cement-water glass slurry is better than that of cement slurry and the grouting quality decreases with initial pressure.

WASTE SOLIDIFICATION BUILDING BENCH SCALE HIGH ACTIVITY WASTE SIMULANT VARIABILITY STUDY FY2008

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

Hansen, E; Timothy Jones, T; Tommy Edwards, T

2009-03-20

The primary objective of this task was to perform a variability study of the high activity waste (HAW) acidic feed to determine the impact of feed variability on the quality of the final grout and on the mixability of the salt solution into the dry powders. The HAW acidic feeds were processed through the neutralization/pH process, targeting a final pH of 12. These fluids were then blended with the dry materials to make the final waste forms. A secondary objective was to determine if elemental substitution for cost prohibitive or toxic elements in the simulant affects the mixing response, thusmore » providing a more economical simulant for use in full scale tests. Though not an objective, the HAW simulant used in the full scale tests was also tested and compared to the results from this task. A statistically designed test matrix was developed based on the maximum molarity inputs used to make the acidic solutions. The maximum molarity inputs were: 7.39 HNO{sub 3}, 0.11618 gallium, 0.5423 silver, and 1.1032 'other' metals based on their NO{sub 3}{sup -} contribution. Substitution of the elements aluminum for gallium and copper for silver was also considered in this test matrix, resulting in a total of 40 tests. During the NaOH addition, the neutralization/pH adjustment process was controlled to a maximum temperature of 60 C. The neutralized/pH adjusted simulants were blended with Portland cement and zircon flour at a water to cement mass ratio of 0.30. The mass ratio of zircon flour to Portland cement was 1/12. The grout was made using a Hobart N-50 mixer running at low speed for two minutes to incorporate and properly wet the dry solids with liquid and at medium speed for five minutes for mixing. The resulting fresh grout was measured for three consecutive yield stress measurements. The cured grout was measured for set, bleed, and density. Given the conditions of preparing the grout in this task, all of the grouts were visually well mixed prior to preparing the

Design and Control of Chemical Grouting : Volume 3 - Engineering Practice

DOT National Transportation Integrated Search

1983-04-01

Recent improvements in the engineering practice of chemical grouting have provided increased confidence in this method of ground modification. Designers can significantly improve the success of chemical grouting by defining their grouting program obj...

Heat of Hydration of Low Activity Cementitious Waste Forms

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

Nasol, D.

2015-07-23

During the curing of secondary waste grout, the hydraulic materials in the dry mix react exothermally with the water in the secondary low-activity waste (LAW). The heat released, called the heat of hydration, can be measured using a TAM Air Isothermal Calorimeter. By holding temperature constant in the instrument, the heat of hydration during the curing process can be determined. This will provide information that can be used in the design of a waste solidification facility. At the Savannah River National Laboratory (SRNL), the heat of hydration and other physical properties are being collected on grout prepared using three simulantsmore » of liquid secondary waste generated at the Hanford Site. From this study it was found that both the simulant and dry mix each had an effect on the heat of hydration. It was also concluded that the higher the cement content in the dry materials mix, the greater the heat of hydration during the curing of grout.« less

Overview of waste stabilization with cement.

PubMed

Batchelor, B

2006-01-01

Cement can treat a variety of wastes by improving physical characteristics (solidification) and reducing the toxicity and mobility of contaminants (stabilization). Potentially adverse waste-binder interactions are an important consideration because they can limit solidification. Stabilization occurs when a contaminant is converted from the dissolved (mobile) phase to a solid (immobile) phase by reactions, such as precipitation, sorption, or substitution. These reactions are often strongly affected by pH, so the presence of components of the waste that control pH are critical to stabilization reactions. Evaluating environmental impacts can be accomplished in a tiered strategy in which simplest approach would be to measure the maximum amount of contaminant that could be released. Alternatively, the sequence of release can be determined, either by microcosm tests that attempt to simulate conditions in the disposal zone or by mechanistic models that attempt to predict behavior using fundamental characteristics of the treated waste.

Brief overview of the various families of grouts and their aplications

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

Nandts, A.

1989-04-01

It is difficult to maintain an up-to-date overview of all the grouts presently used on the international market. Better grouts are continuously developed and more formulators are making their appearance. Consequently, it is difficult to clearly define all of the products in the industry. This topic has been the subject of numerous papers and textbooks. Most authors, however, only focus on their fields of interest: applications in geotechnical, or rehabilitation, or seepage control in civil engineering, oil or mining industry. There has been a limited transfer of technology from one field to the other because of the enormous differences inmore » magnitude, site conditions and consequently the application techniques. The tools an engineer has are: his expertise in grouting and engineering background, equipment available or to be designed or modified to carry out a particular job, relevant data available from other sciences, and products with a variety of characteristics. This paper concentrates on product selection. The most suitable product for a particular project requires a good understanding of the general chemical and mechanical characteristics of the grout. The grouts have been classified into four categories for the purpose of this paper. There may be other methods of classification; however, this is only an attempt to help the industry with the selection of the most suitable grout for a given application. The four categories are: suspension grouts, chemical grouts, hot melts, and precipitation grouts. 1 fig.« less

Demonstration of close-coupled barriers for subsurface containment of buried waste

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

Dwyer, B.P.

1996-05-01

A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed wastemore » remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration was installed at a benign site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington. The composite barrier was emplaced beneath a 7,500 liter tank. The tank was chosen to simulate a typical DOE Complex waste form. The stresses induced on the waste form were evaluated during barrier construction. The barrier was constructed using conventional jet grouting techniques. Drilling was completed at a 45{degree} angle to the ground, forming a conical shaped barrier with the waste form inside the cone. Two overlapping rows of cylindrical cement columns were grouted in a honeycomb fashion to form the secondary backdrop barrier layer. The primary barrier, a high molecular weight polymer manufactured by 3M Company, was then installed providing a relatively thin inner liner for the secondary barrier. The primary barrier was emplaced by panel jet grouting with a dual wall drill stem, two phase jet grouting system.« less

Modification of hydraulic conductivity in granular soils using waste materials.

PubMed

Akbulut, S; Saglamer, A

2004-01-01

This paper evaluates the use of waste products such as silica fume and fly ash in modification of the granular soils in order to remove some environmental problems and create new useful findings in the field of engineering. It is known that silica fume and fly ash, as well as clay material, are used in geotechnical engineering because of their pozzolanic reactivity and fineness to improve the soil properties needed with respect to engineering purposes. The main objective of this research project was to investigate the use of these materials in geotechnical engineering and to improve the hydraulic properties of soils by means of grouting. For this reason, firstly, suitable grouts in suspension forms were prepared by using silica fume, fly ash, clay and cement in different percentages. The properties of these cement-based grouts were then determined to obtain the desired optimum values for grouting. After that, these grouts were penetrated into the soil samples under pressure. The experimental work indicates that these waste materials and clay improved the physical properties and the fluidity of the cement-based grouts and they also decreased the hydraulic conductivity of the grouted soil samples by sealing the voids of the soil. The results of this study have important findings concerning the use of these materials in soil treatment and the improvement of hydraulic conductivity of the soils.

Environmental Assessment of Selected Cone Penetrometer Grouts and a Tracer

DTIC Science & Technology

1993-08-01

Bentonite Clay ............ ...................... A2 Attapulgite Clay ................................... A22 Microfine Portland Cement...and the tracer are a. Bentonite clay. b. Attapulgite clay. c. Microfine portland cement. d. Joosten grout (calcium silicate grout). e. Urethane grout. f...Inc., on an attapulgite clay product (trade name: Zeogel). " Microfine portland cement. Information was obtained for two micro- fine portland cements

Development of a polymetric grout for the hydrostatic bearing at DSS 14

NASA Technical Reports Server (NTRS)

Mcclung, C. E.; Schwendeman, J. L.; Ball, G. L., III; Jenkins, G. H.; Casperson, R. D.; Gale, G. P.; Riewe, A. A.

1981-01-01

Results of an investigation into the causes of the deterioration and premature failure of the grout under the hydrostatic bearing runner at DSS 14 are reported. Generic types of materials were screened and tested to find a grout material more resistive to the causes of grout failure. Emphasis was placed on the physical properties, strength, modulus of elasticity, and resistance to erosion and chemical attack by oil and unique requirements imposed by each material for mixing, placing, compacting, and cooling. The polymetric grout developed to replace the dry grout is described.

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

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

Cantrell, Kirk J.; Snyder, Michelle M.V.; Wang, Guohui

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushedmore » grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.« less

Monitoring of Grouting Compactness in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

PubMed Central

Jiang, Tianyong; Kong, Qingzhao; Wang, Wenxi; Huo, Linsheng; Song, Gangbing

2016-01-01

A post-tensioning tendon duct filled with grout can effectively prevent corrosion of the reinforcement, maintain bonding behavior between the reinforcement and concrete, and enhance the load bearing capacity of concrete structures. In practice, grouting of the post-tensioning tendon ducts always causes quality problems, which may reduce structural integrity and service life, and even cause accidents. However, monitoring of the grouting compactness is still a challenge due to the invisibility of the grout in the duct during the grouting process. This paper presents a stress wave-based active sensing approach using piezoceramic transducers to monitor the grouting compactness in real time. A segment of a commercial tendon duct was used as research object in this study. One lead zirconate titanate (PZT) piezoceramic transducer with marble protection, called a smart aggregate (SA), was bonded on the tendon and installed in the tendon duct. Two PZT patch sensors were mounted on the top outside surface of the duct, and one PZT patch sensor was bonded on the bottom outside surface of the tendon duct. In the active sensing approach, the SA was used as an actuator to generate a stress wave and the PZT sensors were utilized to detect the wave response. Cement or grout in the duct functions as a wave conduit, which can propagate the stress wave. If the cement or grout is not fully filled in the tendon duct, the top PZT sensors cannot receive much stress wave energy. The experimental procedures simulated four stages during the grout pouring process, which includes empty status, half grouting, 90% grouting, and full grouting of the duct. Experimental results show that the bottom PZT sensor can detect the signal when the grout level increases towards 50%, when a conduit between the SA and PZT sensor is formed. The top PZT sensors cannot receive any signal until the grout process is completely finished. The wavelet packet-based energy analysis was adopted in this research to

The physical model for research of behavior of grouting mixtures

NASA Astrophysics Data System (ADS)

Hajovsky, Radovan; Pies, Martin; Lossmann, Jaroslav

2016-06-01

The paper deals with description of physical model designed for verification of behavior of grouting mixtures when applied below underground water level. Described physical model has been set up to determine propagation of grouting mixture in a given environment. Extension of grouting in this environment is based on measurement of humidity and temperature with the use of combined sensors located within preinstalled special measurement probes around grouting needle. Humidity was measured by combined capacity sensor DTH-1010, temperature was gathered by a NTC thermistor. Humidity sensors measured time when grouting mixture reached sensor location point. NTC thermistors measured temperature changes in time starting from initial of injection. This helped to develop 3D map showing the distribution of grouting mixture through the environment. Accomplishment of this particular measurement was carried out by a designed primary measurement module capable of connecting 4 humidity and temperature sensors. This module also takes care of converting these physical signals into unified analogue signals consequently brought to the input terminals of analogue input of programmable automation controller (PAC) WinPAC-8441. This controller ensures the measurement itself, archiving and visualization of all data. Detail description of a complex measurement system and evaluation in form of 3D animations and graphs is supposed to be in a full paper.

Design and Control of Chemical Grouting : Volume 1 - Construction Control

DOT National Transportation Integrated Search

1983-04-01

This report presents the results of a laboratory and field research program investigating innovative method for design and control of chemical grouting in soils. Chemical grouting practice is reviewed and standard evaluation and measurement technique...

Pullout Performances of Grouted Rockbolt Systems with Bond Defects

NASA Astrophysics Data System (ADS)

Xu, Chang; Li, Zihan; Wang, Shanyong; Wang, Shuren; Fu, Lei; Tang, Chunan

2018-03-01

This paper presents a numerical study on the pullout behaviour of fully grouted rockbolts with bond defects. The cohesive zone model (CZM) is adopted to model the bond-slip behaviour between the rockbolt and grout material. Tensile tests were also conducted to validate the numerical model. The results indicate that the defect length can obviously influence the load and stress distributions along the rockbolt as well as the load-displacement response of the grouted system. Moreover, a plateau in the stress distribution forms due to the bond defect. The linear limit and peak load of the load-displacement response decrease as the defect length increases. A bond defect located closer to the loaded end leads to a longer nonlinear stage in the load-displacement response. However, the peak loads measured from the specimens made with various defect locations are almost approximately the same. The peak load for a specimen with the defects equally spaced along the bolt is higher than that for a specimen with defects concentrated in a certain zone, even with the same total defect length. Therefore, the dispersed pattern of bond defects would be much safer than the concentrated pattern. For the specimen with dispersed defects, the peak load increases with an increase in the defect spacing, even if the total defect length is the same. The peak load for a grouted rockbolt system with defects increases with an increases in the bolt diameter. This work leads to a better understanding of the load transfer mechanism for grouted rockbolt systems with bond defects, and paves the way towards developing a general evaluation method for damaged rockbolt grouted systems.

Corrosion performance of prestressing strands in contact with dissimilar grouts.

DOT National Transportation Integrated Search

2013-01-01

To improve the corrosion protection provided to prestressing strands, anti-bleed grouts are used to fill voids in post-tensioning : ducts that result from bleeding and shrinkage of older Portland Cement grouts. Environmental differences caused by exp...

Finite element Analysis of Semi-Grouting Sleeve Connection Member Based on ABAQUS

NASA Astrophysics Data System (ADS)

Bao, Longsheng; Fan, Qianyu; Wang, Ling

2018-05-01

This paper use investigates the force transfer mechanism and failure form of semi-grouting sleeve members under axial load, analyze the weak points of structural bearing capacity and verify the reliability of the connection of steel bars through finite element analysis software. The results show that adding the axial load to semi-grouting sleeve forms a 45°oblique compression zone, which help to transfer stress between reinforcement, grouting material and sleeve. Because the maximum stress of sleeve doesn’t reach its tensile resistance and the deformation of the sleeve is located at the junction of the grouting and the threaded section when the stress value of steel bars at each end of the semi-grouting sleeve reach its ultimate tensile strength, we conclude that the semi-grouting sleeve members can meet the construction quality requirements and be used to connect the steel bars at the joints of the assembled structures. It is necessary to avoid breaking down, since the deformation section will accumulate large plastic deformation during the processing of the sleeve.

Design and Control of Chemical Grouting : Volume 4 - Executive Summary

DOT National Transportation Integrated Search

1983-04-01

This report focuses on the engineering practice of chemical grouting, summarizing the findings of a study to improve design and control techniques for chemical grouting in soils. Improved methods for the planning, control and evaluation of chemical g...

Coupled Viscous Fluid Flow and Joint Deformation Analysis for Grout Injection in a Rock Joint

NASA Astrophysics Data System (ADS)

Kim, Hyung-Mok; Lee, Jong-Won; Yazdani, Mahmoud; Tohidi, Elham; Nejati, Hamid Reza; Park, Eui-Seob

2018-02-01

Fluid flow modeling is a major area of interest within the field of rock mechanics. The main objective of this study is to gain insight into the performance of grout injection inside jointed rock masses by numerical modeling of grout flow through a single rock joint. Grout flow has been widely simulated using non-Newtonian Bingham fluid characterized by two main parameters of dynamic viscosity and shear yield strength both of which are time dependent. The increasing value of these properties with injection time will apparently affect the parameters representing the grouting performance including grout penetration length and volumetric injection rate. In addition, through hydromechanical coupling a mutual influence between the injection pressure from the one side and the joint opening/closing behavior and the aperture profile variation on the other side is anticipated. This is capable of producing a considerable impact on grout spread within the rock joints. In this study based on the Bingham fluid model, a series of numerical analysis has been conducted using UDEC to simulate the flow of viscous grout in a single rock joint with smooth parallel surfaces. In these analyses, the time-dependent evolution of the grout fluid properties and the hydromechanical coupling have been considered to investigate their impact on grouting performance. In order to verify the validity of these simulations, the results of analyses including the grout penetration length and the injection flow rate were compared with a well-known analytical solution which is available for the simple case of constant grout properties and non-coupled hydraulic analysis. The comparison demonstrated that the grout penetration length can be overestimated when the time-dependent hardening of grout material is not considered. Moreover, due to the HM coupling, it was shown that the joint opening induced by injection pressure may have a considerable increasing impression on the values of penetration length and

Pressurized grout remote backfilling at AML sites near Beulah and Zap, North Dakota

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

Weiner, E.J.; Dodd, W.E.

1999-07-01

The Abandoned Mine Lands (AML) Division of the North Dakota Public Service Commission (PSC) is charged with the reclamation of hazardous abandoned mine sites in North Dakota. Several underground lignite coalmines were operated near the cities of Beulah and Zap, North Dakota, from the early 1900's until about 1955. Coal seams in this area were relatively thick and the overburden generally shallow. As these mines have deteriorated with time, deep collapse features, or sinkholes, have surfaced in many areas. These features are very dangerous, especially when they occur at or near residential and commercial areas and public roads. In themore » past five years, sinkholes have surfaced beneath a commercial building (boat dealership, lounge, and gas station) and beneath a nearby occupied mobile home north of Beulah. sinkholes have also surfaced near KHOL Radio Station in Beulah and in the right of way of a public road south of Zap. The AML Division has conducted several emergency sinkhole-filling projects in these areas. In 1995--97, the AML Division conducted exploratory drilling which confirmed the presence of collapsing underground mines at these sites. The remediation of these sites around Beulah/Zap will take place over several years and involve three or more separate contracts due to budget considerations. In 1997, the AML Division began reclamation at these sties utilizing pressurized grout remote backfilling. In this technique, a cementitious grout is pumped through cased drill holes directly into the mine cavities to fill them and thereby stabilize the surface from collapse. The successful contractor for Phase One of the project was The Concrete Doctor, Inc. (TCDI). This paper will concentrate on Phase One of this work performed from June through September 1997. This project is especially interesting because grout was pumped through holes drilled inside the occupied commercial building. Grout was also pumped through angled holes that intercepted mined workings

Slope Stability Analysis of Waste Dump in Sandstone Open Pit Osielec

NASA Astrophysics Data System (ADS)

Adamczyk, Justyna; Cała, Marek; Flisiak, Jerzy; Kolano, Malwina; Kowalski, Michał

2013-03-01

This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit "Osielec". For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.

Stabilization and Solidification of Nitric Acid Effluent Waste at Y-12

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

Singh, Dileep; Lorenzo-Martin, Cinta

Consolidated Nuclear Security, LLC (CNS) at the Y-12 plant is investigating approaches for the treatment (stabilization and solidification) of a nitric acid waste effluent that contains uranium. Because the pH of the waste stream is 1-2, it is a difficult waste stream to treat and stabilize by a standard cement-based process. Alternative waste forms are being considered. In this regard, Ceramicrete technology, developed at Argonne National Laboratory, is being explored as an option to solidify and stabilize the nitric acid effluent wastes.

Evaluating the cement stabilization of arsenic-bearing iron wastes from drinking water treatment.

PubMed

Clancy, Tara M; Snyder, Kathryn V; Reddy, Raghav; Lanzirotti, Antonio; Amrose, Susan E; Raskin, Lutgarde; Hayes, Kim F

2015-12-30

Cement stabilization of arsenic-bearing wastes is recommended to limit arsenic release from wastes following disposal. Such stabilization has been demonstrated to reduce the arsenic concentration in the Toxicity Characteristic Leaching Procedure (TCLP), which regulates landfill disposal of arsenic waste. However, few studies have evaluated leaching from actual wastes under conditions similar to ultimate disposal environments. In this study, land disposal in areas where flooding is likely was simulated to test arsenic release from cement stabilized arsenic-bearing iron oxide wastes. After 406 days submersed in chemically simulated rainwater, <0.4% of total arsenic was leached, which was comparable to the amount leached during the TCLP (<0.3%). Short-term (18 h) modified TCLP tests (pH 3-12) found that cement stabilization lowered arsenic leaching at high pH, but increased leaching at pH<4.2 compared to non-stabilized wastes. Presenting the first characterization of cement stabilized waste using μXRF, these results revealed the majority of arsenic in cement stabilized waste remained associated with iron. This distribution of arsenic differed from previous observations of calcium-arsenic solid phases when arsenic salts were stabilized with cement, illustrating that the initial waste form influences the stabilized form. Overall, cement stabilization is effective for arsenic-bearing wastes when acidic conditions can be avoided. Copyright © 2015 Elsevier B.V. All rights reserved.

Bio-grout based on microbially induced sand solidification by means of asparaginase activity

PubMed Central

Li, Mengmeng; Fu, Qing-Long; Zhang, Qiuzhuo; Achal, Varenyam; Kawasaki, Satoru

2015-01-01

Bio-grout, a new ground improvement method, has been recently developed to improve the mechanical properties, decrease the permeability of porous materials, reinforce or repair cementitious materials and modify the properties of soil or sand. Bio-grout production depends on microbially induced calcite precipitation (MICP), which is driven mainly by an enzyme, urease. However, urease-based MICP process produces excessive ammonia, in addition to secondary pollution generated by urea that is used as substrate in it. In the present study, we reported asparaginase-based MICP process for sand bio-grout development using Bacillus megaterium, and results were also compared with urease-based bio-grouts. The asparaginase activity led to significantly less ammonia production compared to urease without compromising with desired properties of a novel grout. The UCS of bio-grout was obtained at 980 kPa, while the permeability was decreased substantially. The mineralogical composition of precipitated substance was identified as calcite using XRD and the crystal morphology was observed under SEM. The mass percentage of calcite in bio-grout was calculated by thermogravimetric analysis and XCT verified calcite precipitation in it. The results confirmed that biocalcification by means of bacterial asparaginase is a potential solution for geotechnical problems. The asparaginase-based MICP process could be of wider acceptance in future. PMID:26525435

Stabilization and disposal of Argonne-West low-level mixed wastes in ceramicrete waste forms.

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

Barber, D. B.; Singh, D.; Strain, R. V.

1998-02-17

The technology of room-temperature-setting phosphate ceramics or Ceramicrete{trademark} technology, developed at Argonne National Laboratory (ANL)-East is being used to treat and dispose of low-level mixed wastes through the Department of Energy complex. During the past year, Ceramicrete{trademark} technology was implemented for field application at ANL-West. Debris wastes were treated and stabilized: (a) Hg-contaminated low-level radioactive crushed light bulbs and (b) low-level radioactive Pb-lined gloves (part of the MWIR {number_sign} AW-W002 waste stream). In addition to hazardous metals, these wastes are contaminated with low-level fission products. Initially, bench-scale waste forms with simulated and actual waste streams were fabricated by acid-base reactionsmore » between mixtures of magnesium oxide powders and an acid phosphate solution, and the wastes. Size reduction of Pb-lined plastic glove waste was accomplished by cryofractionation. The Ceramicrete{trademark} process produces dense, hard ceramic waste forms. Toxicity Characteristic Leaching Procedure (TCLP) results showed excellent stabilization of both Hg and Pb in the waste forms. The principal advantage of this technology is that immobilization of contaminants is the result of both chemical stabilization and subsequent microencapsulation of the reaction products. Based on bench-scale studies, Ceramicrete{trademark} technology has been implemented in the fabrication of 5-gal waste forms at ANL-West. Approximately 35 kg of real waste has been treated. The TCLP is being conducted on the samples from the 5-gal waste forms. It is expected that because the waste forms pass the limits set by the EPAs Universal Treatment Standard, they will be sent to a radioactive-waste disposal facility.« less

GROUT HOPPER MODELING STUDY

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

Lee, S.

2011-08-30

The Saltstone facility has a grout hopper tank to provide agitator stirring of the Saltstone feed materials. The tank has about 300 gallon capacity to provide a larger working volume for the grout slurry to be held in case of a process upset, and it is equipped with a mechanical agitator, which is intended to keep the grout in motion and agitated so that it won't start to set up. The dry feeds and the salt solution are already mixed in the mixer prior to being transferred to the hopper tank. The hopper modeling study through this work will focusmore » on fluid stirring and agitation, instead of traditional mixing in the literature, in order to keep the tank contents in motion during their residence time so that they will not be upset or solidified prior to transferring the grout to the Saltstone disposal facility. The primary objective of the work is to evaluate the flow performance for mechanical agitators to prevent vortex pull-through for an adequate stirring of the feed materials and to estimate an agitator speed which provides acceptable flow performance with a 45{sup o} pitched four-blade agitator. In addition, the power consumption required for the agitator operation was estimated. The modeling calculations were performed by taking two steps of the Computational Fluid Dynamics (CFD) modeling approach. As a first step, a simple single-stage agitator model with 45{sup o} pitched propeller blades was developed for the initial scoping analysis of the flow pattern behaviors for a range of different operating conditions. Based on the initial phase-1 results, the phase-2 model with a two-stage agitator was developed for the final performance evaluations. A series of sensitivity calculations for different designs of agitators and operating conditions have been performed to investigate the impact of key parameters on the grout hydraulic performance in a 300-gallon hopper tank. For the analysis, viscous shear was modeled by using the Bingham plastic approximation

Microstructural Effects of Sulphate Attack in Sustainable Grouts for Micropiles.

PubMed

Ortega Álvarez, José Marcos; Esteban Pérez, María Dolores; Rodríguez Escribano, Raúl Rubén; Pastor Navarro, José Luís; Sánchez Martín, Isidro

2016-11-08

Nowadays, the use of micropiles has undergone a great development. In general, they are made with cement grout, reinforced with steel tubing. In Spain, these grouts are prepared using OPC, although the standards do not forbid the use of other cements, like sustainable ones. Micropiles are in contact with soils and groundwater, in which the presence of sulphates is common. Their deleterious effects firstly affect to the microstructure. Then, the aim of this research is to study the effects of sulphate attack in the microstructure of micropiles grouts, prepared with OPC, fly ash and slag commercial cements, compared to their behaviour when they are exposed to an optimum hardening condition. The microstructure evolution has been studied with the non-destructive impedance spectroscopy technique, which has never been used for detecting the effects of sulphate attack when slag and fly ash cements are used. Its results have been contrasted with mercury intrusion porosimetry and "Wenner" resistivity ones. The 28-day compressive strength of grouts has been also determined. The results of microstructure characterization techniques are in agreement, although impedance spectroscopy is the most sensitive for following the changes in the porous network of grouts. The results showed that micropiles made using fly ash and slag cements could have a good performance in contact with aggressive sodium sulphate media, even better than OPC ones.

Microstructural Effects of Sulphate Attack in Sustainable Grouts for Micropiles

PubMed Central

Ortega Álvarez, José Marcos; Esteban Pérez, María Dolores; Rodríguez Escribano, Raúl Rubén; Pastor Navarro, José Luís; Sánchez Martín, Isidro

2016-01-01

Nowadays, the use of micropiles has undergone a great development. In general, they are made with cement grout, reinforced with steel tubing. In Spain, these grouts are prepared using OPC, although the standards do not forbid the use of other cements, like sustainable ones. Micropiles are in contact with soils and groundwater, in which the presence of sulphates is common. Their deleterious effects firstly affect to the microstructure. Then, the aim of this research is to study the effects of sulphate attack in the microstructure of micropiles grouts, prepared with OPC, fly ash and slag commercial cements, compared to their behaviour when they are exposed to an optimum hardening condition. The microstructure evolution has been studied with the non-destructive impedance spectroscopy technique, which has never been used for detecting the effects of sulphate attack when slag and fly ash cements are used. Its results have been contrasted with mercury intrusion porosimetry and “Wenner” resistivity ones. The 28-day compressive strength of grouts has been also determined. The results of microstructure characterization techniques are in agreement, although impedance spectroscopy is the most sensitive for following the changes in the porous network of grouts. The results showed that micropiles made using fly ash and slag cements could have a good performance in contact with aggressive sodium sulphate media, even better than OPC ones. PMID:28774026

Method for stabilizing low-level mixed wastes at room temperature

DOEpatents

Wagh, A.S.; Singh, D.

1997-07-08

A method to stabilize solid and liquid waste at room temperature is provided comprising combining solid waste with a starter oxide to obtain a powder, contacting the powder with an acid solution to create a slurry, said acid solution containing the liquid waste, shaping the now-mixed slurry into a predetermined form, and allowing the now-formed slurry to set. The invention also provides for a method to encapsulate and stabilize waste containing cesium comprising combining the waste with Zr(OH){sub 4} to create a solid-phase mixture, mixing phosphoric acid with the solid-phase mixture to create a slurry, subjecting the slurry to pressure; and allowing the now pressurized slurry to set. Lastly, the invention provides for a method to stabilize liquid waste, comprising supplying a powder containing magnesium, sodium and phosphate in predetermined proportions, mixing said powder with the liquid waste, such as tritium, and allowing the resulting slurry to set. 4 figs.

Method for stabilizing low-level mixed wastes at room temperature

DOEpatents

Wagh, Arun S.; Singh, Dileep

1997-01-01

A method to stabilize solid and liquid waste at room temperature is provided comprising combining solid waste with a starter oxide to obtain a powder, contacting the powder with an acid solution to create a slurry, said acid solution containing the liquid waste, shaping the now-mixed slurry into a predetermined form, and allowing the now-formed slurry to set. The invention also provides for a method to encapsulate and stabilize waste containing cesium comprising combining the waste with Zr(OH).sub.4 to create a solid-phase mixture, mixing phosphoric acid with the solid-phase mixture to create a slurry, subjecting the slurry to pressure; and allowing the now pressurized slurry to set. Lastly, the invention provides for a method to stabilize liquid waste, comprising supplying a powder containing magnesium, sodium and phosphate in predetermined proportions, mixing said powder with the liquid waste, such as tritium, and allowing the resulting slurry to set.

Tank Closure Progress at the Department of Energy's Idaho National Engineering Laboratory Tank Farm Facility

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

Quigley, K.D.; Butterworth, St.W.; Lockie, K.A.

2008-07-01

Significant progress has been made at the U.S. Department of Energy (DOE) Idaho National Laboratory (INL) to empty, clean and close radioactive liquid waste storage tanks at the Idaho Nuclear Technology and Engineering Center (INTEC) Tank Farm Facility (TFF). The TFF includes eleven 1,135.6-kL (300,000-gal) underground stainless steel storage tanks and four smaller, 113.5-kL (30,000-gal) stainless steel tanks, along with tank vaults, interconnecting piping, and ancillary equipment. The TFF tanks have historically been used to store a variety of radioactive liquid waste, including wastes associated with past spent nuclear fuel reprocessing. Although four of the large storage tanks remain inmore » use for waste storage, the other seven 1,135.6-kL (300,000-gal) tanks and the four 113.5-kL (30,000-gal) tanks have been emptied of waste, cleaned and filled with grout. A water spray cleaning system was developed and deployed to clean internal tank surfaces and remove remaining tank wastes. The cleaning system was effective in removing all but a very small volume of solid residual waste particles. Recent issuance of an Amended Record of Decision (ROD) in accordance with the National Environmental Policy Act, and a Waste Determination complying with Section 3116 of the Ronald W. Reagan National Defense Authorization Act (NDAA) for Fiscal Year 2005, has allowed commencement of grouting activities on the cleaned tanks. The first three 113.5-kL (30,000-gal) tanks were grouted in the Fall of 2006 and the fourth tank and the seven 1,135.6-kL (300,000-gal) tanks were filled with grout in 2007 to provide long-term stability. It is currently planned that associated tank valve boxes and interconnecting piping, will be stabilized with grout as early as 2008. (authors)« less

Secondary Waste Simulant Development for Cast Stone Formulation Testing

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

Russell, Renee L.; Westsik, Joseph H.; Rinehart, Donald E.

Washington River Protection Solutions, LLC (WRPS) funded Pacific Northwest National Laboratory (PNNL) to conduct a waste form testing program to implement aspects of the Secondary Liquid Waste Treatment Cast Stone Technology Development Plan (Ashley 2012) and the Hanford Site Secondary Waste Roadmap (PNNL 2009) related to the development and qualification of Cast Stone as a potential waste form for the solidification of aqueous wastes from the Hanford Site after the aqueous wastes are treated at the Effluent Treatment Facility (ETF). The current baseline is that the resultant Cast Stone (or grout) solid waste forms would be disposed at the Integratedmore » Disposal Facility (IDF). Data and results of this testing program will be used in the upcoming performance assessment of the IDF and in the design and operation of a solidification treatment unit planned to be added to the ETF. The purpose of the work described in this report is to 1) develop simulants for the waste streams that are currently being fed and future WTP secondary waste streams also to be fed into the ETF and 2) prepare simulants to use for preparation of grout or Cast Stone solid waste forms for testing.« less

Environmental Technology Verification Report: Grouts for Wastewater Collection Systems, Separation Systems Consultants Inc., GST3 Grout

EPA Science Inventory

Municipalities are discovering rapid degradation of infrastructures in wastewater collection and treatment facilities due to infiltration of leaking water from the surrounding environments. Rehabilitation of these facilities by in situ methods, including the use of grouting, is u...

Environmental Technology Verification Report: Grouts for Wastewater Collection Systems, Warren Environmental, Inc. 301-04 Epoxy Grout

EPA Science Inventory

Municipalities are discovering rapid degradation of infrastructures in wastewater collection and treatment facilities due to infiltration of leaking water from the surrounding environments. Rehabilitation of these facilities by in situ methods, including the use of grouting, is u...

A simplified approach for slope stability analysis of uncontrolled waste dumps.

PubMed

Turer, Dilek; Turer, Ahmet

2011-02-01

Slope stability analysis of municipal solid waste has always been problematic because of the heterogeneous nature of the waste materials. The requirement for large testing equipment in order to obtain representative samples has identified the need for simplified approaches to obtain the unit weight and shear strength parameters of the waste. In the present study, two of the most recently published approaches for determining the unit weight and shear strength parameters of the waste have been incorporated into a slope stability analysis using the Bishop method to prepare slope stability charts. The slope stability charts were prepared for uncontrolled waste dumps having no liner and leachate collection systems with pore pressure ratios of 0, 0.1, 0.2, 0.3, 0.4 and 0.5, considering the most critical slip surface passing through the toe of the slope. As the proposed slope stability charts were prepared by considering the change in unit weight as a function of height, they reflect field conditions better than accepting a constant unit weight approach in the stability analysis. They also streamline the selection of slope or height as a function of the desired factor of safety.

Experimental studies on the physico-mechanical properties of jet-grout columns in sandy and silty soils

NASA Astrophysics Data System (ADS)

Akin, Muge K.

2016-04-01

The term of ground improvement states to the modification of the engineering properties of soils. Jet-grouting is one of the grouting methods among various ground improvement techniques. During jet-grouting, different textures of columns can be obtained depending on the characteristics of surrounding subsoil as well as the adopted jet-grouting system for each site is variable. In addition to textural properties, strength and index parameters of jet-grout columns are highly affected by the adjacent soil. In this study, the physical and mechanical properties of jet-grout columns constructed at two different sites in silty and sandy soil conditions were determined by laboratory tests. A number of statistical relationships between physical and mechanical properties of soilcrete were established in this study in order to investigate the dependency of numerous variables. The relationship between qu and γd is more reliable for sandy soilcrete than that of silty columns considering the determination coefficients. Positive linear relationships between Vp and γd with significantly high determination coefficients were obtained for the jet-grout columns in silt and sand. The regression analyses indicate that the P-wave velocity is a very dominant parameter for the estimation of physical and mechanical properties of jet-grout columns and should be involved during the quality control of soilcrete material despite the intensive use of uniaxial compressive strength test. Besides, it is concluded that the dry unit weight of jet-grout column is a good indicator of the efficiency of employed operational parameters during jet-grouting.

Grout compactness monitoring of concrete-filled fiber-reinforced polymer tube using electromechanical impedance

NASA Astrophysics Data System (ADS)

Shi, Yaokun; Luo, Mingzhang; Li, Weijie; Song, Gangbing

2018-05-01

The concrete-filled fiber-reinforced polymer tube (CFFT) is a type of structural element widely used in corrosive environments. Poor grout compactness results in incomplete contact or even no contact between the fiber-reinforced polymer (FRP) tube and the concrete grout, which reduces the load bearing capacity of a CFFT. The monitoring of grout compactness for CFFTs is important. The piezoceramic-based electromechanical impedance (EMI) method has emerged as an efficient and low-cost structural health monitoring technique. This paper presents a feasibility study using the EMI method to monitor grout compactness of CFFTs. In this research, CFFT specimens with different levels of compactness (empty, 1/5, 1/3, 1/2, 2/3, and full compactness) were prepared and subjected to EMI measurement by using four piezoceramic patches that were bonded circumferentially along the outer surface of the CFFT. To analyze the correlation between grout compactness and EMI signatures, a compactness index (CI) was proposed based on the root-mean-square deviation (RMSD). The experimental results show that the changes in admittance signatures are able to determine the grout compactness qualitatively. The proposed CI is able to effectively identify the compactness of the CFFT, and provides location information of the incomplete concrete infill.

Application of resistivity monitoring to evaluate cement grouting effect in earth filled dam

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

Kim, Jin-Mo; Yoon, Wang-Jung

In this paper, we applied electrical resistivity monitoring method to evaluate the cement grouting effect. There are a lot of ways to evaluate cement grouting effect. In order to do this evaluation in a great safety, high efficiency, and lower cost, resistivity monitoring is found to be the most appropriate technique. In this paper we have selected a dam site from Korea to acquire resistivity monitoring data and compare the results of inversion to estimate the cement grouting effect.

An alternative soil nailing system for slope stabilization: Akarpiles

NASA Astrophysics Data System (ADS)

Lim, Chun-Lan; Chan, Chee-Ming

2017-11-01

This research proposes an innovative solution for slope stabilization with less environmental footprint: AKARPILES. In Malaysia, landslide has become common civil and environmental problems that cause impacts to the economy, safety and environment. Therefore, effective slope stabilization method helps to improve the safety of public and protect the environment. This study focused on stabilizing surfacial slope failure. The idea of AKARPILES was generated from the tree roots system in slope stabilization. After the piles are installed in the slope and intercepting the slip plane, grout was pumped in and discharged through holes on the piles. The grout then filled the pores in the soil with random flow within the slip zone. SKW mixture was used to simulate the soil slope. There were two designs being proposed in this study and the prototypes were produced by a 3D printer. Trial mix of the grout was carried out to obtain the optimum mixing ratio of bentonite: cement: water. A series of tests were conducted on the single-pile-reinforced slope under vertical slope crest loading condition considering different slope gradients and nail designs. Parameters such as ultimate load, failure time and failure strain were recorded and compared. As comparison with the unreinforced slope, both designs of AKARPILES showed better but different performances in the model tests.

Criteria: waste tank isolation and stabilization

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

Metz, W.P.; Ogren, W.E.

1976-09-01

The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly. (DLC)

Application of soil nails to the stability of mine waste slopes

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

Tant, C.R.; Drumm, E.C.; Mauldon, M.

1996-12-31

The traditional soil nailed structure incorporates grouted or driven nails, and a wire mesh reinforced shotcrete facing to increase the stability of a slope or wall. This paper describes the construction and monitoring of a full-scale demonstration of nailing to stabilize coal mine spoil. The purpose of the investigation is to evaluate the performance of nailed slopes in mine spoil using methods proven for the stabilization of soil walls and slopes. The site in eastern Tennessee is a 12 meter high slope of dumped fill, composed of weathered shale chips, sandstone, and coal. The slope was formed by {open_quotes}pre-regulatory{close_quotes} contourmore » surface mining operations and served as a work bench during mining. The material varies in size from silt to boulders, and has a small amount of cohesion. Portions of the mine spoil slope have experienced slope instability and erosion which have hampered subsequent reclamation activities. Three different nail spacings and three different nail lengths were used in the design. The 12 meter high structure is instrumented to permit measurement of nail strain, and vertical inclinometer readings and survey measurements will be used for the detection of ground movement. The results of this study will aid in the development of design recommendations and construction guidelines for the application of soil nailing to stabilize mine spoil.« less

Simulation of Grouting Process in Rock Masses Under a Dam Foundation Characterized by a 3D Fracture Network

NASA Astrophysics Data System (ADS)

Deng, Shaohui; Wang, Xiaoling; Yu, Jia; Zhang, Yichi; Liu, Zhen; Zhu, Yushan

2018-06-01

Grouting plays a crucial role in dam safety. Due to the concealment of grouting activities, complexity of fracture distribution in rock masses and rheological properties of cement grout, it is difficult to analyze the effects of grouting. In this paper, a computational fluid dynamics (CFD) simulation approach of dam foundation grouting based on a 3D fracture network model is proposed. In this approach, the 3D fracture network model, which is based on an improved bootstrap sampling method and established by VisualGeo software, can provide a reliable and accurate geometric model for CFD simulation of dam foundation grouting. Based on the model, a CFD simulation is performed, in which the Papanastasiou regularized model is used to express the grout rheological properties, and the volume of fluid technique is utilized to capture the grout fronts. Two sets of tests are performed to verify the effectiveness of the Papanastasiou regularized model. When applying the CFD simulation approach for dam foundation grouting, three technical issues can be solved: (1) collapsing potential of the fracture samples, (2) inconsistencies in the geometric model in actual fractures under complex geological conditions, and (3) inappropriate method of characterizing the rheological properties of cement grout. The applicability of the proposed approach is demonstrated by an illustrative case study—a hydropower station dam foundation in southwestern China.

STABILIZATION OF LEAD-BASED PAINT WASTE

EPA Science Inventory

This study evaluated the ability of a cementitious stabilizing agent to reduce leachable lead from lead-based paint waste removed from substrate via blasting, and to evaluate the mechanism by which the reduction occurs. Testing demonstrated that the representative cementitious ag...

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

Grouting applications in civil engineering. Volume I and II. [800 references

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

Einstein, H.H.; Barvenik, M.J.

1975-01-01

A comprehensive description of grouting applications in civil engineering is presented that can serve as a basis for the selection of grouting methods in the borehole sealing problem. The breadth and depth of the study was assured by conducting the main part of the review, the collection and evaluation of information, without specifically considering the borehole sealing problem (but naturally incorporating any aspect of civil engineering applications that could be of potential use). Grouting is very much an art and not a science. In most cases, it is a trial and error procedure where an inexpensive method is initially triedmore » and then a more expensive one is used until the desired results are obtained. Once a desired effect is obtained, it is difficult to credit any one procedure with the success because the results are due to the summation of all the methods used. In many cases, the method that proves successful reflects a small abnormality in the ground or structure rather than its overall characteristics. Hence, successful grouting relies heavily on good engineering judgement and experience, and not on a basic set of standard correlations or equations. 800 references. (JRD)« less

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

Seismic Performance of Columns with Grouted Couplers in Idaho Accelerated Bridge Construction Applications

DOT National Transportation Integrated Search

2016-10-16

n Accelerated Bridge Construction (ABC) methods, one way to connect prefabricated columns is by using grouted steel bar couplers. As of October 2016, in the U.S., only Utah DOT allows the use of grouted couplers in plastic hinge locations in seismic ...

Analysis on pile testing results of post-grouting bored pile

NASA Astrophysics Data System (ADS)

Zheng, A. R.

2017-04-01

Based on static load test results, the bearing capacity of bored piles with pile-toe and pile-shaft post-grouting has been analyzed. The analysis reveals that: with post-grouting, the interface between pile and surrounding soil are strengthened and the relative sliding displacement in between is reduced; end resistance of pile is enhanced and can be mobilized at earlier stage with smaller sliding displacement. As a result, the performance of bored pile is improved with increased bearing capacity and reduced settlement.

Technical area status report for waste destruction and stabilization

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

Dalton, J.D.; Harris, T.L.; DeWitt, L.M.

1993-08-01

The Office of Environmental Restoration and Waste Management (EM) was established by the Department of Energy (DOE) to direct and coordinate waste management and site remediation programs/activities throughout the DOE complex. In order to successfully achieve the goal of properly managing waste and the cleanup of the DOE sites, the EM was divided into five organizations: the Office of Planning and Resource Management (EM-10); the Office of Environmental Quality Assurance and Resource Management (EM-20); the Office of Waste Operations (EM-30); the Office of Environmental Restoration (EM-40); and the Office of Technology and Development (EM-50). The mission of the Office ofmore » Technology Development (OTD) is to develop treatment technologies for DOE`s operational and environmental restoration wastes where current treatment technologies are inadequate or not available. The Mixed Waste Integrated Program (MWIP) was created by OTD to assist in the development of treatment technologies for the DOE mixed low-level wastes (MLLW). The MWIP has established five Technical Support Groups (TSGs) whose purpose is to identify, evaluate, and develop treatment technologies within five general technical areas representing waste treatment functions from initial waste handling through generation of final waste forms. These TSGs are: (1) Front-End Waste Handling, (2) Physical/Chemical Treatment, (3) Waste Destruction and Stabilization, (4) Second-Stage Destruction and Offgas Treatment, and (5) Final Waste Forms. This report describes the functions of the Waste Destruction and Stabilization (WDS) group. Specifically, the following items are discussed: DOE waste stream identification; summary of previous efforts; summary of WDS treatment technologies; currently funded WDS activities; and recommendations for future activities.« less

Measurement of rock mass deformation with grouted coaxial antenna cables

NASA Astrophysics Data System (ADS)

Dowding, C. H.; Su, M. B.; O'Connor, K.

1989-01-01

Techniques presented herein show how reflected voltage pulses from coaxial antenna cable grouted in rock masses can be employed to quantify the type and magnitude of rock mass deformation. This measurement is similar to that obtained from a combined full profile extensometer (to measure local extension) and inclinometer (to measure local shearing). Rock mass movements deform the grouted cable, which locally changes cable capacitance and thereby the reflected wave form of the voltage pulse. Thus, by monitoring changes in these reflection signatures, it is possible to monitor rock mass deformation. This paper presents laboratory measurements necessary to quantitatively interpret the reflected voltage signatures. Cables were sheared and extended to correlate measured cable deformation with reflected voltage signals. Laboratory testing included development of grout mixtures with optimum properties for field installation and performance of a TDR (Time Domain Reflectometry) monitoring system. Finally, the interpretive techniques developed through laboratory measurements were applied to previously collected field data to extract hitherto unrealized information.

Evaluation of grout behind the lining of shield tunnels using ground-penetrating radar in the Shanghai Metro Line, China

NASA Astrophysics Data System (ADS)

Xie, Xiongyao; Liu, Yujian; Huang, Hongwei; Du, Jun; Zhang, Fengshou; Liu, Lanbo

2007-09-01

For shield tunnelling construction in soft soil areas, the coverage uniformity and quality of consolidation of the injected grout mortar behind the prefabricated tunnel segment is the main concern for tunnel safety and ground settlement. In this paper, ground-penetrating radar (GPR) was applied to evaluate the grout behind the tunnel lining segments in Shanghai, China. The dielectric permittivity of the grout material in Shanghai Metro tunnelling construction was measured in the laboratory. Combining physical modelling results with finite different time domain numerical modelling results, we suggest that the antenna with frequency 200 MHz is well suited to penetrate the reinforced steel bar network of the tunnel lining segment and testing grout patterns behind the segment. The electromagnetic velocity of the grout behind the segment of the tunnel is 0.1 m ns-1 by the analysis of field common-middle point data. A wave-translated method was put forward to process the GPR images. Furthermore, combining the information acquired by GPR with experience data, a GPR non-destructive test standard for the grout mortar evaluation in Shanghai Metro tunnel construction was brought forward. The grout behind the tunnel lining segment is classified into three types: uncompensated grout mortar with a thickness less than 10 cm, normal grout mortar with a thickness between 10 cm and 30 cm and overcompensated grout mortar, which is more than 30 cm thick. The classified method is easily put into practice.

A two-stage ceramic tile grout sealing process using a high power diode laser—Grout development and materials characteristics

NASA Astrophysics Data System (ADS)

Lawrence, J.; Li, L.; Spencer, J. T.

1998-04-01

Work has been conducted using a 60 Wcw high power diode laser (HPDL) in order to determine the feasibility and characteristics of sealing the void between adjoining ceramic tiles with a specially developed grout material having an impermeable enamel surface glaze. A two-stage process has been developed using a new grout material which consists of two distinct components: an amalgamated compound substrate and a glazed enamel surface; the amalgamated compound seal providing a tough, heat resistant bulk substrate, whilst the enamel provides an impervious surface. HPDL processing has resulted in crack free seals produced in normal atmospheric conditions. The basic process phenomena are investigated and the laser effects in terms of seal morphology, composition and microstructure are presented. Also, the resultant heat affects are analysed and described, as well as the effects of the shield gases, O 2 and Ar, during laser processing. Tiles were successfully sealed with power densities as low as 500 W/cm 2 and at rates up to 600 mm/min. Contact angle measurements revealed that due to the wettability characteristics of the amalgamated oxide compound grout (AOCG), laser surface treatment was necessary in order to alter the surface from a polycrystalline to a semi-amorphous structure, thus allowing the enamel to adhere. Bonding of the enamel to the AOCG and the ceramic tiles was identified as being principally due to van der Waals forces, and on a very small scale, some of the base AOCG material dissolving into the glaze.

Development of Freshwater Grout Subsequent to the Bell Canyon Tests (BCT).

DTIC Science & Technology

1986-04-01

specimens of those grouts cured and studied in the SL, to three-years age. Selected data from earlier tests of related fresh-water grouts are...specimens were either coated with a strippable plastic momn;rane, or sealed in plastic cylinders with tightly fitting lids. Sealed in plastiC habs in...for expansion prisms, the strippable coating applied to SPDV specimens did not prevent water loss. Lower strength gain may be attributable to partial

Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

PubMed Central

Jiang, Tianyong; Song, Gangbing

2017-01-01

With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors’ previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD). To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA) developed to utilize one Lead Zirconate Titanate (PZT) transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon duct. PMID

Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers.

PubMed

Jiang, Tianyong; Zheng, Junbo; Huo, Linsheng; Song, Gangbing

2017-09-29

With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors' previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD). To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA) developed to utilize one Lead Zirconate Titanate (PZT) transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon duct.

Factors affecting hazardous waste solidification/stabilization: a review.

PubMed

Malviya, Rachana; Chaudhary, Rubina

2006-09-01

Solidification/stabilization is accepted as a well-established disposal technique for hazardous waste. As a result many different types of hazardous wastes are treated with different binders. The S/S products have different property from waste and binders individually. The effectiveness of S/S process is studied by physical, chemical and microstructural methods. This paper summarizes the effect of different waste stream such as heavy metals bearing sludge, filter cake, fly ash, and slag on the properties of cement and other binders. The factors affecting strength development is studied using mix designs, including metal bearing waste alters the hydration and setting time of binders. Pore structure depends on relative quantity of the constituents, cement hydration products and their reaction products with admixtures. Carbonation and additives can lead to strength improvement in waste-binder matrix.

Microbially Induced Carbonate Precipitation: a Novel Grout for Permeability Control in Subsurface Engineering Works

NASA Astrophysics Data System (ADS)

Minto, J. M.; Hingerl, F.; Lunn, R. J.; Benson, S. M.

2016-12-01

ContextWe utilise the urea hydrolysing capability of soil bacteria Sporosarcina pasteurii to precipitate CaCO3 in a process termed Microbially Induced Carbonate Precipitation (MICP). MICP injection fluid properties are low particle size and low viscosity giving excellent grout penetrability. The CaCO3 grout has been shown to be effective at reducing permeability in porous and fractured media. MICP has consequently been proposed as an alternative to more traditional cement and chemical grouts, particularly in the fields of radioactive waste disposal and geological sequestration of CO2. This study investigates the role of fluid flow/CaCO3 feedback during precipitation and accelerated dissolution to better understand the longevity of an MICP grout under low pH environmental conditions such as found in a carbon sequestration reservoir. MethodsExperiments were conducted on a single Berea sandstone core in a high pressure core holder to characterise permeability, porosity and multiphase flow behaviour at sequestration reservoir temperature and pressure. Characterisation was carried out before MICP, after MICP, and after accelerated dissolution with hydrochloric acid. At each step the entire core was scanned in a medical x-ray CT scanner to spatially resolve (with a resolution of 0.5x0.5x1mm) the changes in porosity and saturation with CaCO3 precipitation and dissolution. Finally, the dried core was scanned with μ-CT at 30μm (full core) and 10μm (sub-volume) resolutions to investigate structural changes to the Berea at near pore scale. ResultsSix MICP treatment cycles over two days reduced core permeability from 886 mDarcy to 40 mDarcy with a greater reduction in porosity at the inlet. Dissolution with acid restored much of the porosity, but did not restore permeability to the same extent. Preferential flow paths formed during the dissolution step were visible in the first 4mm of the 100mm core, but did not extend further into the core. DiscussionThis study provides

Development of laboratory test methods to replace the simulated high-temperature grout fluidity test.

DOT National Transportation Integrated Search

2014-06-01

This report contains a summary of the research performed to develop a replacement for the high-temperature grout : fluidity (HTGF) test. The HTGF test was employed in the past by FDOT to qualify post-tensioning (PT) grouts for use in : post-tensioned...

SEMINAR PROCEEDINGS: RCRA CORRECTIVE ACTION STABILIZATION TECHNOLOGIES

EPA Science Inventory

The seminar publication provides an overview of many technologies that can be used in applying the stabilization concept to RCRA cleanup activities. Technologies discussed include covers, grouting, slurry walls, hydrofracture, horizontal well drilling, a vacuum extraction, and b...

Research status and future trends on surface pre-grouting technology in reforming wall rock of vertical shafts in coal mines in China

NASA Astrophysics Data System (ADS)

Wang, Hua

2018-02-01

In the mine construction, the surface pre-grouting technology is an important method to prevent water blast in excavation process of vertical shaft when the shaft must pass through the thick, water-rich and high water-pressure bedrock aquifer. It has been nearly 60 years since the technology was used to reform wall rock of vertical shaft in coal mine in China for the first time, and the existing technology can basically meet the needs of constructing 1000m deep vertical shaft. Firstly, the article introduces that in view of Magg’s spherical seepage theory and Karol’s spherical seepage theory, Chinese scholars found that the diffusion of grout from borehole into the surrounding strata in horizontal direction is irregular through a lot of research and engineering practice of using the surface pre-grouting technology to reform wall rock of vertical shafts, and put forward the selecting principles of grout’s effective diffusion radius in one grouting engineering; Secondly, according to the shape of the grouting boreholes, surface pre-grouting technology of vertical shaft is divided into two stages: vertical borehole stage and S-type borehole stage. Thirdly, the development status of grouting materials and grouting equipment for the technology is introduced. Fourthly, grouting mode, stage height and pressure of the technology are introduced. Finally, it points out that with the increasing depth of coal mining in China, the technology of reforming wall rock of 1000~2000m deep vertical shafts will face many problems, such as grouting theory, grouting equipment, grouting finishing standard, testing and evaluation of grouting effect, and so on. And it put forward a preliminary approach to solving these problems. This paper points out future research directions of the surface pre-grouting technology in China.

Development and application of new composite grouting material for sealing groundwater inflow and reinforcing wall rock in deep mine.

PubMed

Jinpeng, Zhang; Limin, Liu; Futao, Zhang; Junzhi, Cao

2018-04-04

With cement, bentonite, water glass, J85 accelerator, retarder and water as raw materials, a new composite grouting material used to seal groundwater inflow and reinforce wall rock in deep fractured rock mass was developed in this paper. Based on the reaction mechanism of raw material, the pumpable time, stone rate, initial setting time, plastic strength and unconfined compressive strength of multi-group proportion grouts were tested by orthogonal experiment. Then, the optimum proportion of composite grouting material was selected and applied to the grouting engineering for sealing groundwater inflow and reinforcing wall rock in mine shaft lining. The results show the mixing proportion of the maximum pumpable time, maximum stone rate and minimum initial setting time of grout are A K4 B K1 C K4 D K2 , A K3 B K1 C K1 D K4 and A K3 B K3 C K4 D K1 , respectively. The mixing proportion of the maximum plastic strength and unconfined compressive strength of grouts concretion bodies are A K1 B K1 C K1 D K3 and A K1 B K1 C K1 D K1 , respectively. Balanced the above 5 indicators overall and determined the optimum proportion of grouts: bentonite-cement ratio of 1.0, water-solid ratio of 3.5, accelerator content of 2.9% and retarder content of 1.45%. This new composite grouting material had good effect on the grouting engineering for sealing groundwater inflow and reinforcing wall rock in deep fractured rock mass.

A portable high-power diode laser-based single-stage ceramic tile grout sealing system

NASA Astrophysics Data System (ADS)

Lawrence, J.; Schmidt, M. J. J.; Li, L.; Edwards, R. E.; Gale, A. W.

2002-02-01

By means of a 60 W high-power diode laser (HPDL) and a specially developed grout material the void between adjoining ceramic tiles has been successfully sealed. A single-stage process has been developed which uses a crushed ceramic tile mix to act as a tough, inexpensive bulk substrate and a glazed enamel surface to provide an impervious surface glaze. The single-stage ceramic tile grout sealing process yielded seals produced in normal atmospheric conditions that displayed no discernible cracks and porosities. The single-stage grout is simple to formulate and easy to apply. Tiles were successfully sealed with power densities as low as 200 kW/ mm2 and at rates of up to 600 mm/ min. Bonding of the enamel to the crushed ceramic tile mix was identified as being primarily due to van der Waals forces and, on a very small scale, some of the crushed ceramic tile mix material dissolving into the glaze. In terms of mechanical, physical and chemical characteristics, the single-stage ceramic tile grout was found to be far superior to the conventional epoxy tile grout and, in many instances, matched and occasionally surpassed that of the ceramic tiles themselves. What is more, the development of a hand-held HPDL beam delivery unit and the related procedures necessary to lead to the commercialisation of the single-stage ceramic tile grout sealing process are presented. Further, an appraisal of the potential hazards associated with the use of the HPDL in an industrial environment and the solutions implemented to ensure that the system complies with the relevant safety standards are given.

Treatment of Bottled Liquid Waste During Remediation of the Hanford 618-10 Burial Ground - 13001

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

Faulk, Darrin E.; Pearson, Chris M.; Vedder, Barry L.

2013-07-01

A problematic waste form encountered during remediation of the Hanford Site 618-10 burial ground consists of bottled aqueous waste potentially contaminated with regulated metals. The liquid waste requires stabilization prior to landfill disposal. Prior remediation activities at other Hanford burial grounds resulted in a standard process for sampling and analyzing liquid waste using manual methods. Due to the highly dispersible characteristics of alpha contamination, and the potential for shock sensitive chemicals, a different method for bottle processing was needed for the 618-10 burial ground. Discussions with the United States Department of Energy (DOE) and United States Environmental Protection Agency (EPA)more » led to development of a modified approach. The modified approach involves treatment of liquid waste in bottles, up to one gallon per bottle, in a tray or box within the excavation of the remediation site. Bottles are placed in the box, covered with soil and fixative, crushed, and mixed with a Portland cement grout. The potential hazards of the liquid waste preclude sampling prior to treatment. Post treatment verification sampling is performed to demonstrate compliance with land disposal restrictions and disposal facility acceptance criteria. (authors)« less

Numerical Analysis on Tensile Properties of Grout-filled Splice Sleeve Rebars under ISO 834 Standard Fire

NASA Astrophysics Data System (ADS)

Liu, Yong Jun; Li, Chao; Zhou, When Jun

2018-06-01

This paper presents some numerical simulation results of tensile properties of reinforcing bars spliced by grout-filled coupling sleeves under fire conditions to identify the effect of load ratio on fire resistance time of spliced reinforcing bars, which provide a useful base for predicting structural behaviors of pre-cast reinforced concrete buildings in fires. A spliced rebar system investigated in this paper consists of two equal-diameter steel reinforcing bars with 25mm diameter and a straight coupling sleeve with 50mm outer and 45mm inner diameters. As a result, the thickness of grout between steel bars and sleeves are 20mm. Firstly, the temperature distributions in steel bars connected by grout- filled coupling sleeves exposed to ISO 834 standard fire were calculated utilizing finite element analysis software ANSYS. Secondly, the stress changes in heated steel bars connected by grout-filled coupling sleeves under different constant tensile loads were calculated step by step until the rebar system failed due to fire. Thus, the fire resistant time of rebar spliced by grout-filled coupling sleeves under different axial tensile loads can be determined, further, the relationship between fire resistance time and axial tensile loads ratio can could be obtained. Finally, the fire resistant times versus axial tensile load ratios curve of grout-filled splice sleeve rebars exposed to ISO 834 standard fire is presented.

Determining the Release of Radionuclides from Tank 18F Waste Residual Solids: FY2016 Report

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

King, William D.; Hobbs, David T.

Pore water leaching studies were conducted on actual Savannah River Site (SRS) Tank 18F residual waste solids to support Liquid Waste tank closure efforts. A test methodology was developed during previous simulant testing to produce slurries of tank residual solids and grout-representative solids in grout pore water solutions (based on SRS groundwater compositions) with pH and E h values expected during the aging of the closed waste tank. The target conditions are provided below where the initial pore water has a reducing potential and a relatively high pH (Reducing Region II). The pore water is expected to become increasingly oxidizingmore » with time (Oxidizing Region II) and during the latter stages of aging (Oxidizing Region III) the pH is expected to decrease. For the reducing case, tests were conducted with both unwashed and washed Tank 18F residual solids. For the oxidizing cases (Oxidizing Regions II and III), all samples were washed with simulated grout pore water solutions prior to testing, since it is expected that these conditions will occur after considerable pore water solution has passed through the system. For the reducing case, separate tests were conducted with representative ground grout solids and with calcium carbonate reagent, which is the grout phase believed to be controlling the pH. Ferrous sulfide (FeS) solids were also added to the reducing samples to lower the slurry E h value. Calcium carbonate solids were used as the grout-representative solid phase for each of the oxidizing cases. Air purge-gas with and without CO 2 removed was transferred through the oxidizing test samples and nitrogen purge-gas was transferred through the reducing test samples during leach testing. The target pH values were achieved to within 0.5 pH units for all samples. Leaching studies were conducted over an E h range of approximately 0.7 V. However, the highest and lowest E h values achieved of ~+0.5 V and ~-0.2 V were significantly less positive and less

Review of Potential Candidate Stabilization Technologies for Liquid and Solid Secondary Waste Streams

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

Pierce, Eric M.; Mattigod, Shas V.; Westsik, Joseph H.

2010-01-30

Pacific Northwest National Laboratory has initiated a waste form testing program to support the long-term durability evaluation of a waste form for secondary wastes generated from the treatment and immobilization of Hanford radioactive tank wastes. The purpose of the work discussed in this report is to identify candidate stabilization technologies and getters that have the potential to successfully treat the secondary waste stream liquid effluent, mainly from off-gas scrubbers and spent solids, produced by the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Down-selection to the most promising stabilization processes/waste forms is needed to support the design of a solidificationmore » treatment unit (STU) to be added to the Effluent Treatment Facility (ETF). To support key decision processes, an initial screening of the secondary liquid waste forms must be completed by February 2010.« less

Bond of Field-Cast Grouts to Precast Concrete Elements

DOT National Transportation Integrated Search

2017-01-01

The performance of connections between prefabricated concrete elements constructed using field-cast cementitious grouts and groutlike materials is becoming a focus area for accelerated bridge construction (ABC) projects. These connections are require...

Leaching behaviour and mechanical properties of copper flotation waste in stabilized/solidified products.

PubMed

Mesci, Başak; Coruh, Semra; Ergun, Osman Nuri

2009-02-01

This research describes the investigation of a cement-based solidification/stabilization process for the safe disposal of copper flotation waste and the effect on cement properties of the addition of copper flotation waste (CW) and clinoptilolite (C). In addition to the reference mixture, 17 different mixtures were prepared using different proportions of CW and C. Physical properties such as setting time, specific surface area and compressive strength were determined and compared to a reference mixture and Turkish standards (TS). Different mixtures with the copper flotation waste portion ranging from 2.5 to 12.5% by weight of the mixture were tested for copper leachability. The results show that as cement replacement materials especially clinoptilolite had clear effects on the mechanical properties. Substitution of 5% copper flotation waste for Portland cement gave a similar strength performance to the reference mixture. Higher copper flotation waste addition such as 12.5% replacement yielded lower strength values. As a result, copper flotation waste and clinoptilolite can be used as cementitious materials, and copper flotation waste also can be safely stabilized/solidified in a cement-based solidification/stabilization system.

ECONOMICS OF GROUND FREEZING FOR MANAGEMENT OF UNCONTROLLED HAZARDOUS WASTE SITES

EPA Science Inventory

Ground freezing for hazardous waste containment is an alternative to the traditional and expensive slurry wall or grout curtain barrier technologies. The parameters quantified in this analysis of it include thermal properties, refrigeration line spacing, equipment mobilization an...

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

Simulation of prepackaged grout bleed under field conditions.

DOT National Transportation Integrated Search

2014-04-01

This report contains a summary of the research performed in the area of reproducing and determining the cause of soft : grout, which has been found in several PT (Post-Tensioned) tubes around the state of Florida. A modified version of the : Euronorm...

Waste Management Project fiscal year 1998 multi-year work plan, WBS 1.2

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

Jacobsen, P.H.

The Waste Management Project manages and integrates (non-TWRS) waste management activities at the site. Activities include management of Hanford wastes as well as waste transferred to Hanford from other DOE, Department of Defense, or other facilities. This work includes handling, treatment, storage, and disposal of radioactive, nonradioactive, hazardous, and mixed solid and liquid wastes. Major Waste Management Projects are the Solid Waste Project, Liquid Effluents Project, and Analytical Services. Existing facilities (e.g., grout vaults and canyons) shall be evaluated for reuse for these purposes to the maximum extent possible.

Liquid secondary waste: Waste form formulation and qualification

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

Cozzi, A. D.; Dixon, K. L.; Hill, K. A.

The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, including Direct Feed Low Activity Waste (DFLAW) vitrification, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. The powdered salt waste form produced by the ETF will be replaced by a stabilized solidified waste form for disposal in Hanford’s Integrated Disposal Facility (IDF). Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilizationmore » Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the IDF. Waste form testing to support this plan is composed of work in the near term to provide data as input to a performance assessment (PA) for Hanford’s IDF. In 2015, three Hanford Liquid Secondary Waste simulants were developed based on existing and projected waste streams. Using these waste simulants, fourteen mixes of Hanford Liquid Secondary Waste were prepared and tested varying the waste simulant, the water-to-dry materials ratio, and the dry materials blend composition.1 In FY16, testing was performed using a simulant of the EMF process condensate blended with the caustic scrubber—from the Low Activity Waste (LAW) melter—, processed through the ETF. The initial EMF-16 simulant will be based on modeling efforts performed to determine the mass balance of the ETF for the DFLAW.2 The compressive strength of all of the mixes exceeded the target of 3.4 MPa (500 psi) to meet the requirements identified as potential IDF Waste Acceptance Criteria in Table 1 of the Secondary Liquid Waste Immobilization Technology Development Plan.3 The hydraulic properties of the waste forms tested (hydraulic

Effects of using silica fume and polycarboxylate-type superplasticizer on physical properties of cementitious grout mixtures for semiflexible pavement surfacing.

PubMed

Koting, Suhana; Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S; Ibrahim, Mohd Rasdan; Katman, Herdayati; Husain, Nadiah Md

2014-01-01

Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout.

Demonstration of ATG Process for Stabilizing Mercury (<260 ppm) Contaminated Mixed Waste. Mixed Waste Focus Area. OST Reference # 2407

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

None, None

1999-09-01

Mercury contaminated wastes in many forms are present at various U. S. Department of Energy (DOE) sites. Based on efforts led by the Mixed Waste Focus Area (MWFA) and its Mercury Working Group (HgWG), the inventory of wastes contaminated with <260 ppm mercury and with radionuclides stored at various DOE sites is estimated to be approximately 6,000 m 3). At least 26 different DOE sites have this type of mixed low-level waste in their storage facilities. Extraction methods are required to remove mercury from waste containing >260 ppm levels, but below 260 ppm Hg contamination levels the U. S. Environmentalmore » Protection Agency (EPA) does not require removal of mercury from the waste. Steps must still be taken, however, to ensure that the final waste form does not leach mercury in excess of the limit for mercury prescribed in the Resource Conservation and Recovery Act (RCRA) when subjected to the Toxicity Characteristic Leaching Procedure (TCLP). At this time, the limit is 0.20 mg/L. However, in the year 2000, the more stringent Universal Treatment Standard (UTS) of 0.025 mg/L will be used as the target endpoint. Mercury contamination in the wastes at DOE sites presents a challenge because it exists in various forms, such as soil, sludges, and debris, as well as in different chemical species of mercury. Stabilization is of interest for radioactively contaminated mercury waste (<260 ppm Hg) because of its success with particular wastes, such as soils, and its promise of applicability to a broad range of wastes. However, stabilization methods must be proven to be adequate to meet treatment standards. It must also be proven feasible in terms of economics, operability, and safety. To date, no standard method of stabilization has been developed and proven for such varying waste types as those within the DOE complex.« less

Radioactive nuclear waste stabilization - Aspects of solid-state molecular engineering and applied geochemistry

NASA Technical Reports Server (NTRS)

Haggerty, S. E.

1983-01-01

Stabilization techniques for the storage of radioactive wastes are surveyed, with emphasis on immobilization in a primary barrier of synthetic rock. The composition, half-life, and thermal-emission characteristics of the wastes are shown to require thermally stable immobilization enduring at least 100,000 years. Glass materials are determined to be incapable of withstanding the expected conditions, average temperatures of 100-500 C for the first 100 years. The geological-time stability of crystalline materials, ceramics or synthetic rocks, is examined in detail by comparing their components with similar naturally occurring minerals, especially those containing the same radioactive elements. The high-temperature environment over the first 100 years is seen as stabilizing, since it can recrystallize radiation-induced metamicts. The synthetic-rock stabilization technique is found to be essentially feasible, and improvements are suggested, including the substitution of nepheline with freudenbergite and priderite for alkaline-waste stabilization, the maintenance of low oxygen fugacity, and the dilution of the synthetic-rock pellets into an inert medium.

Secondary Waste Cementitious Waste Form Data Package for the Integrated Disposal Facility Performance Assessment

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

Cantrell, Kirk J.; Westsik, Joseph H.; Serne, R Jeffrey

A review of the most up-to-date and relevant data currently available was conducted to develop a set of recommended values for use in the Integrated Disposal Facility (IDF) performance assessment (PA) to model contaminant release from a cementitious waste form for aqueous wastes treated at the Hanford Effluent Treatment Facility (ETF). This data package relies primarily upon recent data collected on Cast Stone formulations fabricated with simulants of low-activity waste (LAW) and liquid secondary wastes expected to be produced at Hanford. These data were supplemented, when necessary, with data developed for saltstone (a similar grout waste form used at themore » Savannah River Site). Work is currently underway to collect data on cementitious waste forms that are similar to Cast Stone and saltstone but are tailored to the characteristics of ETF-treated liquid secondary wastes. Recommended values for key parameters to conduct PA modeling of contaminant release from ETF-treated liquid waste are provided.« less

SUBGRADE MONOLITHIC ENCASEMENT STABILIZATION OF CATEGORY 3 LOW LEVEL WASTE (LLW)

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

PHILLIPS, S.J.

2004-02-03

A highly efficient and effective technology has been developed and is being used for stabilization of Hazard Category 3 low-level waste at the U.S. Department of Energy's Hanford Site. Using large, structurally interconnected monoliths, which form one large monolith that fills a waste disposal trench, the patented technology can be used for final internment of almost any hazardous, radioactive, or toxic waste or combinations of these waste materials packaged in a variety of sizes, shapes, and volumes within governmental regulatory limits. The technology increases waste volumetric loading by 100 percent, area use efficiency by 200 percent, and volumetric configuration efficiencymore » by more than 500 percent over past practices. To date, in excess of 2,010 m{sup 3} of contact-handled and remote-handled low-level radioactive waste have been interned using this patented technology. Additionally, in excess of 120 m{sup 3} of low-level radioactive waste requiring stabilization in low-diffusion coefficient waste encasement matrix has been disposed using this technology. Greater than five orders of magnitude in radiation exposure reduction have been noted using this method of encasement of Hazard Category 3 waste. Additionally, exposure monitored at all monolith locations produced by the slip form technology is less than 1.29 x E-07 C {center_dot} kg{sup -1}. Monolithic encasement of Hazard Category 3 low-level waste and other waste category materials may be successfully accomplished using this technology at nominally any governmental or private sector waste disposal facility. Additionally, other waste materials consisting of hazardous, radioactive, toxic, or mixed waste materials can be disposed of using the monolithic slip form encasement technology.« less

Effects of Using Silica Fume and Polycarboxylate-Type Superplasticizer on Physical Properties of Cementitious Grout Mixtures for Semiflexible Pavement Surfacing

PubMed Central

Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S.; Katman, Herdayati; Husain, Nadiah Md

2014-01-01

Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout. PMID:24526911

[Novel process utilizing alkalis assisted hydrothermal process to stabilize heavy metals both from municipal solid waste or medical waste incinerator fly ash and waste water].

PubMed

Wang, Lei; Jin, Jian; Li, Xiao-dong; Chi, Yong; Yan, Jian-hua

2010-08-01

An alkalis assisted hydrothermal process was induced to stabilize heavy metals both from municipal solid waste or medical waste incinerator fly ash and waste water. The results showed that alkalis assisted hydrothermal process removed the heavy metals effectively from the waste water, and reduced leachability of fly ash after process. The heavy metal leachabilities of fly ash studied in this paper were Mn 17,300 microg/L,Ni 1650 microg/L, Cu 2560 microg/L, Zn 189,000 microg/L, Cd 1970 microg/L, Pb 1560 microg/L for medical waste incinerator fly ash; Mn 17.2 microg/L, Ni 8.32 microg/L, Cu 235.2 microg/L, Zn 668.3 microg/L, Cd 2.81 microg/L, Pb 7200 microg/L for municipal solid waste incinerator fly ash. After hydrothermal process with experimental condition [Na2CO3 dosage (5 g Na2CO3/50 g fly ash), reaction time = 10 h, L/S ratio = 10/1], the heavy metal removal efficiencies of medical waste incinerator fly ash were 86.2%-97.3%, and 94.7%-99.6% for municipal solid waste incinerator fly ash. The leachabilities of both two kinds of fly ash were lower than that of the Chinese national limit. The mechanism of heavy metal stabilization can be concluded to the chemisorption and physically encapsulation effects of aluminosilicates during its formation, crystallization and aging process, the high pH value has some contribution to the heavy metal removal and stabilization.

Research on Anchorage Performance of Grouting Anchor Connection of Precast Concrete Structure

NASA Astrophysics Data System (ADS)

Wang, Donghui; Liu, Xudong; Wang, Sheng; Cao, Xixi

2018-03-01

The bonding of grouted anchor bars is one of the vertical connection forms of steel bars in fabricated concrete structures. The performance of grouted connection is mainly affected by the anchorage length and lap length of steel bars. The mechanisms of bond and anchorage between steel bar and concrete are analyzed, and the factors that influence the anchorage performance of steel bar are systematically summarized. Results show that the bond and anchorage performance of steel and concrete have been studied widely, but there are still shortcomings, and the connection forms need to be further improved.

Use of fly-ash slurry in backfill grouting in coal mines.

PubMed

Jiang, Ning; Zhao, Jinhai; Sun, Xizhen; Bai, Liyang; Wang, Changxiang

2017-11-01

Cave backfill grouting implies grouting of the caving rock mass prior to it being compacted. The filling materials strengthen the caving rock and support the overlying strata to achieve the purpose of slowing down the surface subsidence. The broken roof will fail and collapse during mining operations performed without appropriate supporting measures being taken. It is difficult to perform continuous backfill mining on the working face of such roofs using the existing mining technology. In order to solve the above problems, fly ash and mine water are considered as filling materials, and flow characteristics of fly-ash slurry are investigated through laboratory experiments and theoretical analyses. Laws governing the diffusion of fly-ash slurry in the void of caving rock masses and in the void between a caving rock mass and a basic roof are obtained and verified. Based on the results obtained from the above analyses and actual conditions at the Zhaoguan coal mine, Shandong Province, China, a cave backfill grouting system of the hauling pipeline is developed and successfully tested at the 1703 working face in the Zhaoguan coal mine. The results demonstrate that a filling rate of 43.46% is achieved, and the surface subsidence coefficient of the grouting process is found to be 0.475. Compared to the total caving method, the proposed system is found to achieve a reduction rate of 40.63%. This effectively helps in lowering the value of the surface subsidence coefficient. Fly ash and mine water, considered as primary materials in this study, also play a significant role in improving the air quality and water environment.

Measurements of Mercury Released from Solidified/Stabilized Waste Forms

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

Mattus, C.H.

2001-04-19

This report covers work performed during FY 1999-2000 in support of treatment demonstrations conducted for the Mercury Working Group of the U.S. Department of Energy (DOE) Mixed Waste Focus Area. In order to comply with the requirements of the Resource Conservation and Recovery Act, as implemented by the U.S. Environmental Protection Agency (EPA), DOE must use one of these procedures for wastes containing mercury at levels above 260 ppm: a retorting/roasting treatment or an incineration treatment (if the wastes also contain organics). The recovered radioactively contaminated mercury must then be treated by an amalgamation process prior to disposal. The DOEmore » Mixed Waste Focus Area and Mercury Working Group are working with the EPA to determine if some alternative processes could treat these types of waste directly, thereby avoiding for DOE the costly recovery step. They sponsored a demonstration in which commercial vendors applied their technologies for the treatment of two contaminated waste soils from Brookhaven National Laboratory. Each soil was contaminated with {approx}4500 ppm mercury; however, one soil had as a major radioelement americium-241, while the other contained mostly europium-152. The project described in this report addressed the need for data on the mercury vapor released by the solidified/stabilized mixed low-level mercury wastes generated during these demonstrations as well as the comparison between the untreated and treated soils. A related work began in FY 1998, with the measurement of the mercury released by amalgamated mercury, and the results were reported in ORNL/TM-13728. Four treatments were performed on these soils. The baseline was obtained by thermal treatment performed by SepraDyne Corp., and three forms of solidification/stabilization were employed: one using sulfur polymer cement (Brookhaven National Laboratory), one using portland cement [Allied Technology Group (ATG)], and a third using proprietary additives (Nuclear Fuel

MINE WASTE TECHNOLOGY PROGRAM; PHOSPHATE STABILIZATION OF HEAVY METALS CONTAMINATED MINE WASTE YARD SOILS, JOPLIN, MISSOURI NPL SITE

EPA Science Inventory

This document summarizes the results of Mine Waste Technology Project 22-Phosphate Stabilization of Heavy Metals-Contaminated Mine Waste Yard Soils. Mining, milling, and smelting of ores near Joplin, Missouri, have resulted in heavy metal contamination of the area. The Joplin s...

Development of chemically bonded phosphate ceramics for stabilizing low-level mixed wastes

NASA Astrophysics Data System (ADS)

Jeong, Seung-Young

1997-11-01

Novel chemically bonded phosphate ceramics have been developed by acid-base reactions between magnesium oxide and an acid phosphate at room temperature for stabilizing U.S. Department of Energy's low-level mixed waste streams that include hazardous chemicals and radioactive elements. Newberyite (MgHPOsb4.3Hsb2O)-rich magnesium phosphate ceramic was formed by an acid-base reaction between phosphoric acid and magnesium oxide. The reaction slurry, formed at room-temperature, sets rapidly and forms stable mineral phases of newberyite, lunebergite, and residual MgO. Rapid setting also generates heat due to exothermic acid-base reaction. The reaction was retarded by partially neutralizing the phosphoric acid solution by adding sodium or potassium hydroxide. This reduced the rate of reaction and heat generation and led to a practical way of producing novel magnesium potassium phosphate ceramic. This ceramic was formed by reacting stoichiometric amount of monopotassium dihydrogen phosphate crystals, MgO, and water, forming pure-phase of MgKPOsb4.6Hsb2O (MKP) with moderate exothermic reaction. Using this chemically bonded phosphate ceramic matrix, low-level mixed waste streams were stabilized, and superior waste forms in a monolithic structure were developed. The final waste forms showed low open porosity and permeability, and higher compression strength than the Land Disposal Requirements (LDRs). The novel MKP ceramic technology allowed us to develop operational size waste forms of 55 gal with good physical integrity. In this improved waste form, the hazardous contaminants such as RCRA heavy metals (Hg, Pb, Cd, Cr, Ni, etc) were chemically fixed by their conversion into insoluble phosphate forms and physically encapsulated by the phosphate ceramic. In addition, chemically bonded phosphate ceramics stabilized radioactive elements such U and Pu. This was demonstrated with a detailed stabilization study on cerium used as a surrogate (chemically equivalent but nonradioactive

Analytical Study of the Mechanical Behavior of Fully Grouted Bolts in Bedding Rock Slopes

NASA Astrophysics Data System (ADS)

Liu, C. H.; Li, Y. Z.

2017-09-01

Bolting is widely used as a reinforcement means for rock slopes. The support force of a fully grouted bolt is often provided by the combination of the axial and shear forces acting at the cross section of the bolt, especially for bedding rock slopes. In this paper, load distribution and deformation behavior of the deflecting section of a fully grouted bolt were analyzed, and a structural mechanical model was established. Based on force method equations and deformation compatibility relationships, an analytical approach, describing the contribution of the axial and shear forces acting at the intersection between the bolt and the joint plane to the stability of a rock slope, was developed. Influence of the inclination of the bolt to the joint plane was discussed. Laboratory tests were conducted with different inclinations of the bolt to the joint plane. Comparisons between the proposed approach, the experimental data and a code method were made. The calculation results are in good agreement with the test data. It is shown that transverse shear resistance plays a significant role to the bolting contribution and that the bigger the dip of the bolt to the joint plane, the more significant the dowel effect. It is also shown that the design method suggested in the code overestimates the resistance of the bolt. The proposed model considering dowel effect provides a more precise description on bolting properties of bedding rock slopes than the code method and will be helpful to improve bolting design methods.

SURVEY OF SOLIDIFICATION/STABILIZATION TECHNOLOGY FOR HAZARDOUS INDUSTRIAL WASTES

EPA Science Inventory

Stabilization/solidification or fixation is a process for treating industrial solid wastes (primarily sludges) that contain hazardous constituents to prevent dissolution and loss of toxic materials into the environment. Most of these treatment processes are designed to produce a ...

Efficiency of jet grout columns and sand-recycled material mixtures for mitigating liquefaction damage

NASA Astrophysics Data System (ADS)

Kerem Ertek, M.; Demir, Gökhan; Köktan, Utku

2017-04-01

Liquefaction is an important seismic phenomena that has to be assessed and consequently makes it essential to take measures in order to reduce related hazards. There are several ways to assess liquefaction potential analytically and some constitutive models implemented in FEM softwares presenting cyclic behaviour of sand making it possible to observe shear strain or excess pore pressure ratio which are measures to hold a view about liquefaction occurrence. According to various studies in the literature, post-earthquake inspections show that the measures in terms of grouting, piled rafts and sand mixtures with different non-liquefiable materials reduce liquefaction related damage. This paper aims to provide a brief information about effectiveness of jet-grout columns and recycled material-sand mixtures against liquefaction by the help of numerical analyses performed with MIDAS GTS NX software with regard to generation of shear strains. Key words: liquefaction, numerical analyses, jet-grout, sand mixtures

Validation of enhanced stabilization of municipal solid waste under controlled leachate recirculation using FTIR and XRD.

PubMed

Sethi, Sapna; Kothiyal, N C; Nema, Arvind K

2012-07-01

Leachate recirculation at neutral PH accompanied with buffer/nutrients addition has been used successfully in earlier stabilization of municipal solid waste in bioreactor landfills. In the present study, efforts were made to enhance the stabilization rate of municipal solid waste (MSW) and organic solid waste (OSW) in simulated landfill bioreactors by controlling the pH of recirculated leachate towards slightly alkaline side in absence of additional buffer and nutrients addition. Enhanced stabilization in waste samples was monitored with the help of analytical tools like Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Predominance of bands assigned to inorganic compounds and comparatively lower intensities of bands for organic compounds in the FTIR spectra of waste samples degraded with leachate recirculation under controlled pH confirmed higher rate of biodegradation and mineralization of waste than the samples degraded without controlled leachate recirculation. XRD spectra also confirmed to a greater extent of mineralization in the waste samples degraded under leachate recirculation with controlled pH. Comparison of XRD spectra of two types of wastes pointed out higher degree of mineralization in organic solid waste as compared to municipal solid waste.

Properties of Tuffs, Grout and Other Materials.

DTIC Science & Technology

1982-01-01

analysis , and tested in uniaxial strain. Table 2 presents the physical properties, ultrasonic data, and the per- manent volume compaction resulting from the... methods provide an accuracy of ±2% on pressure and stress measure- ments. Strain Measurements - Strains are measured using cantilever arms inside the...that are used in nuclear blast effects analysis , and specifically to assist in the analysis of the grout sphere explosive tests being conducted by the

Time-Lapse Electrical Resistivity Investigations for Imaging the Grouting Injection in Shallow Subsurface Cavities

PubMed Central

Farooq, Muhammad; Kim, Jung Ho; Song, Young Soo; Amjad Sabir, Mohammad; Umar, Muhammad; Tariq, Mohammad; Muhammad, Said

2014-01-01

The highway of Yongweol-ri, Muan-gun, south-western part of the South Korean Peninsula, is underlain by the abandoned of subsurface cavities, which were discovered in 2005. These cavities lie at shallow depths with the range of 5∼15 meters below the ground surface. Numerous subsidence events have repeatedly occurred in the past few years, damaging infrastructure and highway. As a result of continuing subsidence issues, the Korean Institute of Geosciences and Mineral Resources (KIGAM) was requested by local administration to resolve the issue. The KIGAM used geophysical methods to delineate subsurface cavities and improve more refined understanding of the cavities network in the study area. Cement based grouting has been widely employed in the construction industry to reinforce subsurface ground. In this research work, time-lapse electrical resistivity surveys were accomplished to monitor the grouting injection in the subsurface cavities beneath the highway, which have provided a quasi-real-time monitoring for modifying the subsurface cavities related to ground reinforcement, which would be difficult with direct methods. The results obtained from time-lapse electrical resistivity technique have satisfactory imaged the grouting injection experiment in the subsurface cavities beneath the highway. Furthermore, the borehole camera confirmed the presence of grouting material in the subsurface cavities, and hence this procedure increases the mechanical resistance of subsurface cavities below the highway. PMID:24578621

Time-lapse electrical resistivity investigations for imaging the grouting injection in shallow subsurface cavities.

PubMed

Farooq, Muhammad; Park, Samgyu; Kim, Jung Ho; Song, Young Soo; Amjad Sabir, Mohammad; Umar, Muhammad; Tariq, Mohammad; Muhammad, Said

2014-01-01

The highway of Yongweol-ri, Muan-gun, south-western part of the South Korean Peninsula, is underlain by the abandoned of subsurface cavities, which were discovered in 2005. These cavities lie at shallow depths with the range of 5∼15 meters below the ground surface. Numerous subsidence events have repeatedly occurred in the past few years, damaging infrastructure and highway. As a result of continuing subsidence issues, the Korean Institute of Geosciences and Mineral Resources (KIGAM) was requested by local administration to resolve the issue. The KIGAM used geophysical methods to delineate subsurface cavities and improve more refined understanding of the cavities network in the study area. Cement based grouting has been widely employed in the construction industry to reinforce subsurface ground. In this research work, time-lapse electrical resistivity surveys were accomplished to monitor the grouting injection in the subsurface cavities beneath the highway, which have provided a quasi-real-time monitoring for modifying the subsurface cavities related to ground reinforcement, which would be difficult with direct methods. The results obtained from time-lapse electrical resistivity technique have satisfactory imaged the grouting injection experiment in the subsurface cavities beneath the highway. Furthermore, the borehole camera confirmed the presence of grouting material in the subsurface cavities, and hence this procedure increases the mechanical resistance of subsurface cavities below the highway.

Conceptual design statement of work for the immobilized low-activity waste interim storage facility project

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

Carlson, T.A., Fluor Daniel Hanford

1997-02-06

The Immobilized Low-Activity Waste Interim Storage subproject will provide storage capacity for immobilized low-activity waste product sold to the U.S. Department of Energy by the privatization contractor. This statement of work describes the work scope (encompassing definition of new installations and retrofit modifications to four existing grout vaults), to be performed by the Architect-Engineer, in preparation of a conceptual design for the Immobilized Low-Activity Waste Interim Storage Facility.

Stabilization/solidification of an alkyd paint waste by carbonation of waste-lime based formulations.

PubMed

Arce, R; Galán, B; Coz, A; Andrés, A; Viguri, J R

2010-05-15

The application of solvent-based paints by spraying in paint booths is extensively used in a wide range of industrial activities for the surface treatment of a vast array of products. The wastes generated as overspray represent an important environmental and managerial problem mainly due to the hazardous characteristics of the organic solvent, rendering it necessary to appropriately manage this waste. In this paper a solidification/stabilization (S/S) process based on accelerated carbonation was investigated as an immobilization pre-treatment prior to the disposal, via landfill, of an alkyd solvent-based paint waste coming from the automotive industry; the purpose of this S/S process was to immobilize the contaminants and reduce their release into the environment. Different formulations of paint waste with lime, lime-coal fly-ash and lime-Portland cement were carbonated to study the effect of the water/solid ratio and carbonation time on the characteristics of the final product. To assess the efficiency of the studied S/S process, metals, anions and dissolved organic carbon (DOC) were analyzed in the leachates obtained from a battery of compliance and characterization leaching tests. Regarding the carbonation of paint waste-lime formulations, a mathematical expression has been proposed to predict the results of the leachability of DOC from carbonated mixtures working at water/solid ratios from 0.2 to 0.6. However, lower DOC concentrations in leachates (400mg/kg DOC in L/S=10 batch leaching test) were obtained when carbonation of paint waste-lime-fly-ash mixtures was used at 10h carbonation and water to solid ratio of 0.2. The flammability characteristics, the total contents of contaminants and the contaminant release rate in compliance leaching tests provide evidence for a final product suitable for deposition in non-hazardous landfills. The characterization of this carbonated sample using a dynamic column leaching test shows a high stabilization of metals, partial

Technology Demonstration Summary: International Waste Technologies In Situ Stabilization/Solidification, Hialeah, Florida

EPA Science Inventory

An evaluation was performed of the International Waste Technologies (IWT) HWT-20 additive and the Geo-Con, Inc. deep-soil-mixing equipment for an in situ stabilization/solidification process and its applicability as an on-site treatment method for waste site cleanup. The analysis...

Corrosion of post-tensioned tendons with deficient grout : final report.

DOT National Transportation Integrated Search

2016-10-20

Recent corrosion failures of post-tensioned (PT) tendons in the Ringling Causeway Bridge (and corrosion development of PT tendons elsewhere in Florida) utilizing pre-packaged low-bleed specified grout products have spurred the need to evaluate what m...

Effect of natural ageing on volume stability of MSW and wood waste incineration residues

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

Gori, Manuela, E-mail: manuela.gori@dicea.unifi.it; Bergfeldt, Britta; Reichelt, Jürgen

2013-04-15

Highlights: ► Natural weathering on BA from MSW and wood waste incineration was evaluated. ► Type of mineral phases, pH and volume stability were considered. ► Weathering reactions effect in improved stability of the materials. - Abstract: This paper presents the results of a study on the effect of natural weathering on volume stability of bottom ash (BA) from municipal solid waste (MSW) and wood waste incineration. BA samples were taken at different steps of treatment (fresh, 4 weeks and 12 weeks aged) and then characterised for their chemical and mineralogical composition and for volume stability by means of themore » mineralogical test method (M HMVA-StB), which is part of the German quality control system for using aggregates in road construction (TL Gestein-StB 04). Changes of mineralogical composition with the proceeding of the weathering treatment were also monitored by leaching tests. At the end of the 12 weeks of treatment, almost all the considered samples resulted to be usable without restrictions in road construction with reference to the test parameter volume stability.« less

Field testing of jet-grouted piles and drilled shafts.

DOT National Transportation Integrated Search

2014-01-01

A field study of deep foundations supporting high mast lighting and signage was undertaken in typical Florida : soils. Three drilled shafts (48 in x12 ft and two 48 in x18 ft) and two jet-grouted piles (28 in x18 ft) were : constructed in Keystone He...

An FHWA Special Study: Post-Tensioning Tendon Grout Chloride Thresholds

DOT National Transportation Integrated Search

2014-05-01

"Elevated levels of chloride were recently discovered in a commercially available pre-bagged grout product made for : post-tensioned (PT) tendons. Chloride concentrations were reported to be as high as 5.27 percent by weight of cement. : These number...

GROUTING TECHNIQUES IN BOTTOM SEALING OF HAZARDOUS WASTE SITES

EPA Science Inventory

Bottom sealing of hazardous waste sites involves the injection or insertion of an inert impermeable and continuous horizontal barrier in soil below the source of contamination. This type of containment strategy could be used in conjunction with other technology such as slurry wal...

Chemical stabilization of air pollution control residues from municipal solid waste incineration.

PubMed

Quina, Margarida J; Bordado, João C M; Quinta-Ferreira, Rosa M

2010-07-15

The by-products of the municipal solid waste incineration (MSWI) generally contain hazardous pollutants, with particular relevance to air pollution control (APC) residues. This waste may be harmful to health and detrimental to the environmental condition, mainly due to soluble salts, toxic heavy metals and trace organic compounds. Solidification/stabilization (S/S) with binders is a common industrial technology for treating such residues, involving however, a significant increase in the final mass that is landfilled. In our work, the chemical stabilization of APC residues by using NaHS x xH(2)O, H(3)PO(4), Na(2)CO(3), C(5)H(10)NNaS(2) x 3 H(2)O, Na(2)O x SiO(2) was investigated, and it was possible to conclude that all these additives lead to an improvement of the stabilization process of the most problematic heavy metals. Indeed, compliance leaching tests showed that after the stabilization treatment the waste becomes non-hazardous with respect to heavy metals. Chromium revealed to be a problematic metal, mainly when H(3)PO(4), Na(2)CO(3) and Na(2)O x SiO(2) were used for stabilization. Nevertheless, soluble phosphates are the most efficient additives for stabilizing the overall metals. The effect of the additives tested on the elements associated with soluble salts (K, Na, Cl(-)) is almost negligible, and therefore, the soluble fraction is hardly reduced without further treatment, such as pre-washing. 2010 Elsevier B.V. All rights reserved.

Storage potential and residual emissions from fresh and stabilized waste samples from a landfill simulation experiment.

PubMed

Morello, Luca; Raga, Roberto; Sgarbossa, Paolo; Rosson, Egle; Cossu, Raffaello

2018-05-01

The storage capacity and the potentially residual emissions of a stabilized waste coming from a landfill simulation experiment were evaluated. The evolution in time of the potential emissions and the mobility of some selected elements or compounds were determined, comparing the results of the stabilized waste samples with the values detected in the related fresh waste samples. Analyses were conducted for the total bulk waste and also for each identified category (under-sieve, kitchen residues, green and wooden materials, plastics, cellulosic material and textiles) to highlight the contribution of the different waste fractions in the total emission potential. The waste characterization was performed through analyses on solids and on leaching test eluates; the chemical speciation of carbon, nitrogen, chlorine and sulfur together with the partitioning of heavy metals through a SCE procedure were carried out. Results showed that the under-sieve is the most environmentally relevant fraction, hosting a consistent part of mobile compounds in fresh waste (40.7% of carbon, 44.0% of nitrogen, 47.6% of chloride and 40.0% of sulfur) and the greater part of potentially residual emissions in stabilized waste (88.4% of carbon, 90.9% of nitrogen, 98.4% of chloride and 91.1% of sulfur). Landfilled Municipal Solid Waste (MSW) proved to be an effective sink, finally storing more than 55% of carbon, 53% of nitrogen, 33% of sulfur and 90% of heavy metals (HM) which were initially present in fresh waste samples. A general decrease in leachable fractions from fresh to stabilized waste was observed for each category. Tests showed that solid waste is not a good sink for chlorine, whose residual non-mobile fraction amounts to 12.3% only. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of a grout curtain on groundwater regime in karst: the example of the Ðale reservoir (Croatia)

NASA Astrophysics Data System (ADS)

Bonacci, Ognjen; Roje-Bonacci, Tanja

2010-05-01

Construction of grout curtains in karst terrains is primarily connected with dams and reservoirs. Their role is to increase watertightness and prevent progressive erosion. In this presentation hourly continuous measurement of groundwater level in two deep piezometers near the Đale reservoir is analysed. The Đale reservoir in the Cetina River began operation in 1989. The total length of the grout curtain is 3.9 km. It spreads 120 m bellow the Đale dam. First analysed piezometer A is drilled in the interior part of the system, between the reservoir and the grout curtain, while the second one B is located in its external part. Distance between them is 200 m. In natural conditions, prior the grout curtain construction, groundwater level fluctuation in both of them was similar (practically the same). Construction of the grout curtain extremely changed groundwater behaviour in each of them. During the six month of continuous monitoring, differences between groundwater levels in them range between +19.86 m (groundwater in B is lower than in A) and -12.77 m (groundwater in A is lower than in B). During the 77% of analysed period the groundwater level in interior piezometer A is higher than the groundwater level in external piezometer B. In other 23% of analysed period the groundwater level in outside piezometer B is higher than in inside A. The construction of the grout curtain caused unnaturally high hydrostatic gradients, which can accelerate the dissolutional expansion of karst fractures. As a result, unbearable leakage of the reservoir Đale can occur over its lifetime. Careful analyses of groundwater level behaviour discover some other very important characteristics of karst underground morphology.

Detecting grouting quality of tendon ducts using the impact-echo method

NASA Astrophysics Data System (ADS)

Qu, Guangzhen; Sun, Min; Zhou, Guangli

2018-06-01

The performance, durability and safety of prestressed concrete bridge were directly affected by the compaction of prestressed pipe. However, the pipe was hidden in the beam, and its grouting density was difficult to detect. The paper had modified three different status of gouting quality through making test model. After that, the impact-Echo method was adopted to detect the grouting quality of tendon ducts, the study was sunmmarized as follow. If the reflect time of slab bottom and nominal thickness of slab increased, the degree of density will increase; testing from half-hole of web, the reflect time and nominal thickness of slab was biggest. At the same time, the reflect time of compacted and uncompacted tendon ducts were mainly. At last, the method was verified by the engineering project, which provided reference value.

Expansive soil stabilization with coir waste and lime for flexible pavement subgrade

NASA Astrophysics Data System (ADS)

Narendra Goud, G.; Hyma, A.; Shiva Chandra, V.; Sandhya Rani, R.

2018-03-01

Expansive soil properties can be improved by various methods to make it suitable for construction of flexible pavement. The coir pith is the by-product (bio-waste) generated from coir industry during extraction of coir fiber from coconut husk. Openly disposed coir pith can make the surrounding areas unhygienic. This bio-waste can be one of the potential materials to stabilize the expansive soils. In the present study coir pith and lime are used as stabilizers. Different combinations of coir pith contents (1%, 2% and 3%) and lime contents (2%, 3% and 4%)are used to study the behavior of expansive soil. Unconfined compressive strength (UCS) of unstabilized and stabilized soils was determined. Optimum content of coir pith and lime are determined based on UCS of the soil. California bearing ratio of soil determined at optimum contents of coir pith and lime. Flexible pavement layer compositions for two levels of traffic using stabilized soil subgrade.

Electrochemical extraction of gold from wastes as nanoparticles stabilized by phospholipids.

PubMed

Moriwaki, Hiroshi; Yamada, Kotaro; Usami, Hisanao

2017-02-01

A simple one-step method for the extraction of gold from wastes as nanoparticles stabilized by phospholipids is demonstrated. This is achieved by applying an AC voltage for 5s to the gold-containing wastes, which act as the electrodes in a buffer solution containing a dispersed phospholipid (1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC). This is an environmentally friendly and rapid method for recovering gold from wastes. The extracted gold nanoparticles have significant potential as a catalyst or biomedical material. Copyright © 2016 Elsevier Ltd. All rights reserved.

Engineering study of 50 miscellaneous inactive underground radioactive waste tanks located at the Hanford Site, Washington

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

Freeman-Pollard, J.R.

1994-03-02

This engineering study addresses 50 inactive underground radioactive waste tanks. The tanks were formerly used for the following functions associated with plutonium and uranium separations and waste management activities in the 200 East and 200 West Areas of the Hanford Site: settling solids prior to disposal of supernatant in cribs and a reverse well; neutralizing acidic process wastes prior to crib disposal; receipt and processing of single-shell tank (SST) waste for uranium recovery operations; catch tanks to collect water that intruded into diversion boxes and transfer pipeline encasements and any leakage that occurred during waste transfer operations; and waste handlingmore » and process experimentation. Most of these tanks have not been in use for many years. Several projects have, been planned and implemented since the 1970`s and through 1985 to remove waste and interim isolate or interim stabilize many of the tanks. Some tanks have been filled with grout within the past several years. Responsibility for final closure and/or remediation of these tanks is currently assigned to several programs including Tank Waste Remediation Systems (TWRS), Environmental Restoration and Remedial Action (ERRA), and Decommissioning and Resource Conservation and Recovery Act (RCRA) Closure (D&RCP). Some are under facility landlord responsibility for maintenance and surveillance (i.e. Plutonium Uranium Extraction [PUREX]). However, most of the tanks are not currently included in any active monitoring or surveillance program.« less

Production of an impermeable composite of irradiated graphite and glass by hot isostatic pressing as a long term leach resistant waste form

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

Fachinger, Johannes; Muller, Walter; Marsat, Eric

2013-07-01

Around 250,000 tons of irradiated graphite (i-graphite) exists worldwide and can be considered as a current waste or future waste stream. The largest national i-graphite inventory is located in UK (∼ 100,000 tons) with significant quantities also in Russia and France [5]. Most of the i-graphite remains in the cores of shutdown nuclear reactors including the MAGNOX type in UK and the UNGG in France. Whilst there are still operational power reactors with graphite cores, such as the Russian RBMKs and the AGRs in UK, all of them will reach their end of life during the next two decades. Themore » most common reference waste management option of i-graphite is a wet or dry retrieval of the graphite blocks from the reactor core and the grouting of these blocks in a container without further conditioning. This produces large waste package volumes because the encapsulation capacity of the grout is limited and large cavities in the graphite blocks could reduce the packing densities. Packing densities from 0.5 to 1 tons per cubic meter have been assumed for grouting solutions. Furthermore the grout is permeable. This could over time allow the penetration of aqueous phases into the waste block and a potential dissolution and release of radionuclides. As a result particularly highly soluble radionuclides may not be retained by the grout. Vitrification could present an alternative, however a similar waste package volume increase may be expected since the encapsulation capacity of glass is potentially similar to or worse than that of grout. FNAG has developed a process for the production of a graphite-glass composite material called Impermeable Graphite Matrix (IGM) [3]. This process is also applicable to irradiated graphite which allows the manufacturing of an impermeable material without volume increase. Crushed i-graphite is mixed with 20 vol.% of glass and then pressed under vacuum at an elevated temperature in an axial hot vacuum press (HVP). The obtained product has zero

Effects of concentrated leachate injection modes on stabilization of landfilled waste.

PubMed

He, Ruo; Wei, Xiao-Meng; Chen, Min; Su, Yao; Tian, Bao-Hu

2016-02-01

Injection of concentrated leachate to landfills is a simple and cost-effective technology for concentrated leachate treatment. In this study, the effects of injection mode of concentrated leachate and its hydraulic loading rate on the stabilization of landfilled waste were investigated. Compared with the injection of concentrated leachate, the joint injection of leachate and concentrated leachate (1:1, v/v) was more beneficial to the degradation of landfilled waste and mitigated the discharge amount of pollutants at the hydraulic loading rate of 5.9 L m(-2) day(-1). As the hydraulic loading rate of the joint injection of leachate and concentrated leachate was increased from 5.9 to 17.6 L m(-2) day(-1), the organic matter, biologically degradable matter, and total nitrogen of landfilled waste were degraded more rapidly, with the degradation constant of the first-order kinetics of 0.005, 0.004, and 0.003, respectively. Additionally, NO2(-)-N and NO3(-)-N in the concentrated leachate could be well removed in the landfill bioreactors. These results showed that a joint injection of concentrated leachate and raw leachate might be a good way to relieve the inhibitory effect of high concentrations of toxic pollutants in the concentrated leachate and accelerate the stabilization of landfilled waste.

Rock Mass Grouting in the Løren Tunnel: Case Study with the Main Focus on the Groutability and Feasibility of Drill Parameter Interpretation

NASA Astrophysics Data System (ADS)

Høien, Are Håvard; Nilsen, Bjørn

2014-05-01

The Løren road tunnel is a part of a major project at Ring road 3 in Oslo, Norway. The rock part of the tunnel is 915 m long and has two tubes with three lanes and breakdown lanes. Strict water ingress restriction was specified and continuous rock mass grouting was, therefore, carried out for the entire tunnel, which was excavated in folded Cambro-Silurian shales intruded by numerous dykes. This paper describes the rock mass grouting that was carried out for the Løren tunnel. Particular emphasis is placed on discussing grout consumption and the challenges that were encountered when passing under a distinct rock depression. Measurement while drilling (MWD) technology was used for this project, and, in this paper, the relationships between the drill parameter interpretation (DPI) factors water and fracturing are examined in relation to grout volumes. A lowering of the groundwater table was experienced during excavation under the rock depression, but the groundwater was nearly re-established after completion of the main construction work. A planned 80-m watertight concrete lining was not required to be built due to the excellent results from grouting in the rock depression area. A relationship was found between leakages mapped in the tunnel and the DPI water factor, indicating that water is actually present where the DPI water factor shows water in the rock. It is concluded that, for the Løren tunnel, careful planning and high-quality execution of the rock mass grouting made the measured water ingress meet the restrictions. For future projects, the DPI water factor may be used to give a better understanding of the material in which the rock mass grouting is performed and may also be used to reduce the time spent and volumes used when grouting.

The relationship between compressive strength and flexural strength of pavement geopolymer grouting material

NASA Astrophysics Data System (ADS)

Zhang, L.; Han, X. X.; Ge, J.; Wang, C. H.

2018-01-01

To determine the relationship between compressive strength and flexural strength of pavement geopolymer grouting material, 20 groups of geopolymer grouting materials were prepared, the compressive strength and flexural strength were determined by mechanical properties test. On the basis of excluding the abnormal values through boxplot, the results show that, the compressive strength test results were normal, but there were two mild outliers in 7days flexural strength test. The compressive strength and flexural strength were linearly fitted by SPSS, six regression models were obtained by linear fitting of compressive strength and flexural strength. The linear relationship between compressive strength and flexural strength can be better expressed by the cubic curve model, and the correlation coefficient was 0.842.

Permeability test and slope stability analysis of municipal solid waste in Jiangcungou Landfill, Shaanxi, China.

PubMed

Yang, Rong; Xu, Zengguang; Chai, Junrui; Qin, Yuan; Li, Yanlong

2016-07-01

With the rapid increase of city waste, landfills have become a major method to deals with municipal solid waste. Thus, the safety of landfills has become a valuable research topic. In this paper, Jiangcungou Landfill, located in Shaanxi, China, was investigated and its slope stability was analyzed. Laboratory tests were used to obtain permeability coefficients of municipal solid waste. Based on the results, the distribution of leachate and stability in the landfill was computed and analyzed. These results showed: the range of permeability coefficient was from 1.0 × 10(-7) cm sec(-1) to 6.0 × 10(-3) cm sec(-1) on basis of laboratory test and some parameters of similar landfills. Owing to the existence of intermediate cover layers in the landfill, the perched water level appeared in the landfill with heavy rain. Moreover, the waste was filled with leachate in the top layer, and the range of leachate level was from 2 m to 5 m in depth under the waste surface in other layers. The closer it gets to the surface of landfill, the higher the perched water level of leachate. It is indicated that the minimum safety factors were 1.516 and 0.958 for winter and summer, respectively. Additionally, the slope failure may occur in summer. The research of seepage and stability in landfills may provide a less costly way to reduce accidents. Landslides often occur in the Jiangcungou Landfill because of the high leachate level. Some measures should be implemented to reduce the leachate level. This paper investigated seepage and slope stability of landfills by numerical methods. These results may provide the basis for increasing stability of landfills.

Review of Literature on Waste Solidification/Stabilization with Emphasis on Metal-Bearing Wastes

DTIC Science & Technology

1989-08-01

applicability to treating a wide variety of waste types, and the ease with 4 which they are implemented in the field (Wiles and Apel , undated). Asphaltic...Wiles, C.C., 1987. A Review of Solidification/Stabilization Technology. Journal of Hazardous Materials, 14:5-21. Wiles, C.C., and Apel , M.L., undated...Personal correspondence and attachments from William McLaughlin, 1-714-693-1818, 1988. Trident Engineering Associates, 48 Maryland Ave., Annapolis, Maryland

The effect of leachate recirculation with enzyme cellulase addition on waste stability in landfill bioreactor

NASA Astrophysics Data System (ADS)

Saffira, N.; Kristanto, G. A.

2018-01-01

Landfill bioreactor with leachate recirculation is known to enhance waste stabilization. However, the composition of waste in Indonesia is comprised by organic waste which is lignocellulosic materials that considered take a long time to degrade under anaerobic condition. To accelerate the degradation process, enzyme addition is ought to do. Cellulase is an enzyme that can catalyse cellulose and other polysaccharide decomposition processes. Therefore, operation of waste degradation using leachate recirculation with a cellulase addition to enhance waste stabilization was investigated using anaerobic bioreactor landfill. The experiment was performed on 2 conditions; leachate recirculation with cellulase addition and recirculation only as a control. The addition of cellulase is reported to be significant in decreasing organic content, represented by volatile solid parameter. The volatile solid reduction in the cellulase augmented reactor and control reactor was 17.86% and 7.90%, respectively. Cellulase addition also resulted in the highest cellulose reduction. Settlement of the landfill in a bioreactor with enzyme addition (32.67%) was reported to be higher than the control (19.33%). Stabilization of landfill review by the decreasing rate constant of the cellulose and lignin ratio parameter was more rapidly achieved by the enzyme addition (0.014 day-1) compared to control (0.002 day-1).

Corrosion performance of prestressing strands in contact with dissimilar grouts : technical summary.

DOT National Transportation Integrated Search

2013-01-01

Inspections of post-tensioned bridges : by the Kansas Department of Transportation : have revealed voids in strand ducts due to : bleeding and shrinkage of older Portland : Cement grouts. The Kansas Department : of Transportation is faced with a deci...

Special Analysis: Disposal of ETF Activated Carbon Vessels in Slit Trenches at the E-Area Low-Level Waste Facility

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

Collard, L.B.

2003-08-25

This Special Analysis (SA) addresses two contaminants of concern, H-3 and I-129, in three Effluent Treatment Facility (ETF) Activated Carbon Vessels awaiting disposal as solid waste. The Unreviewed Disposal Question (UDQ) evaluation listed two options for disposal of this waste, disposal as Components-in-Grout (CIG) or disposal in Slit Trenches with sealed openings to restrict release of H-3 form the vessels. Consumption of the CIG inventory limit and consumption of CIG facility volume are shown for the ETF vessels to allow easy comparison with the consumption of Slit Trench inventory limit and consumption of the Slit Trench facility volume . Themore » inventory projections are based on doubling the inventory of the three ETF vessels in the E-Area to account for the unknown inventory of three ETF vessels in the ETF. When the grout ultimately is assumed to degrade hydraulically, the water movement is not impeded as much as the release is accelerated by the presence of the grout. Under these conditions for the CIG trenches relative to the Slit Trenches, the well concentrations are higher, the inventory limit is lower and for a given inventory the inventory limit consumption is higher.« less

EFFECTS OF LEACHING ON PORE SIZE DISTRIBUTION OF SOLIDIFIED/STABILIZED WASTES

EPA Science Inventory

Chemical solidification/stabilization processes are commonly used to immobilize metals in fly ash and flue gas desulfurization (FGD) sludges and to convert these wastes into monolithic or granular materials with better handling properties and reduced permeabilities. his study eva...

Tank Closure Progress at the Department of Energy's Idaho National Engineering Laboratory Tank Farm Facility

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

Lockie, K.A.; Suttora, L.C.; Quigley, K.D.

2007-07-01

Significant progress has been made at the U.S. Department of Energy (DOE) Idaho National Laboratory (INL) to clean and close emptied radioactive liquid waste storage tanks at the Idaho Nuclear Technology and Engineering Center (INTEC) Tank Farm Facility (TFF). The TFF includes eleven 1,135.6-kL (300,000-gal) underground stainless steel storage tanks and four smaller, 113.5-kL (30,000-gal) stainless steel tanks, along with tank vaults, interconnecting piping, and ancillary equipment. The TFF tanks have historically been used to store a variety of radioactive liquid waste, including wastes associated with past spent nuclear fuel reprocessing. Although four of the large storage tanks remain inmore » use for waste storage, the other seven 1,135.6-kL (300,000-gal) tanks and the four 113.5-kL (30,000-gal) tanks have been emptied of waste and cleaned in preparation of final closure. A water spray cleaning system was developed and deployed to clean internal tank surfaces and remove remaining tank wastes. The cleaning system was effective in removing all but a very small volume of solid residual waste particles. Recent issuance of an Amended Record of Decision (ROD) in accordance with the National Environmental Policy Act, and a Waste Determination complying with Section 3116 of the Ronald W. Reagan National Defense Authorization Act (NDAA) for Fiscal Year 2005, has allowed commencement of grouting activities on the cleaned tanks. In November 2006, three of the 113.5-kL (30,000-gal) tanks were filled with grout to provide long-term stability. It is currently planned that all seven cleaned 1,135.6-kL (300,000-gal) tanks, as well as the four 113.5-kL (30,000-gal) tanks and all associated tank vaults and interconnecting piping, will be stabilized with grout as early as 2008. (authors)« less

Effects of alkalinity sources on the stability of anaerobic digestion from food waste.

PubMed

Chen, Shujun; Zhang, Jishi; Wang, Xikui

2015-11-01

This study investigated the effects of some alkalinity sources on the stability of anaerobic digestion (AD) from food waste (FW). Four alkalinity sources, namely lime mud from papermaking (LMP), waste eggshell (WES), CaCO3 and NaHCO3, were applied as buffer materials and their stability effects were evaluated in batch AD. The results showed that LMP and CaCO3 had more remarkable effects than NaHCO3 and WES on FW stabilization. The methane yields were 120.2, 197.0, 156.2, 251.0 and 194.8 ml g(-1) VS for the control and synergistic digestions of CaCO3, NaHCO3, LMP and WES added into FW, respectively. The corresponding final alkalinity reached 5906, 7307, 9504, 7820 and 6782 mg l(-1), while the final acidities were determined to be 501, 200, 50, 350 and 250 mg l(-1), respectively. This indicated that the synergism between alkalinity and inorganic micronutrients from different alkalinity sources played an important role in the process stability of AD from FW. © The Author(s) 2015.

OVERVIEW OF THE HISTORY, PRESENT STATUS, AND FUTURE DIRECTION OF SOLIDIFICATION/STABILIZATION TECHNOLOGIES FOR HAZARDOUS WASTE TREATMENT

EPA Science Inventory

Solidification/stabilization (S/S) technology processes are currently being utilized in the United States to treat inorganic and organic hazardous waste and radioactive waste. These wastes are generated from operating industry or have resulted from the uncontrolled management of ...

Modeling Nitrogen Decrease in Water Lettuce Ponds from Waste Stabilization Ponds

NASA Astrophysics Data System (ADS)

Putri, Gitta Agnes; Sunarsih

2018-02-01

This paper presents about the dynamic modeling of the Water Lettuce ponds as a form of improvement from the Water Hyacinth ponds. The purpose of this paper is to predict nitrogen decrease and nitrogen transformation in Water Lettuce ponds integrated with Waste Stabilization Ponds. The model consists of 4 mass balances, namely Dissolved Organic Nitrogen (DON), Particulate Organic Nitrogen (PON), ammonium (NH4+), Nitrate and Nitrite (NOx). The process of nitrogen transformation which considered in a Water Lettuce ponds, namely hydrolysis, mineralization, nitrification, denitrification, plant and bacterial uptake processes. Numerical simulations are performed by giving the values of parameters and the initial values of nitrogen compounds based on a review of previous studies. Numerical results show that the rate of change in the concentration of nitrogen compounds in the integration ponds of waste stabilization and water lettuce decreases and reaches stable at different times.

Influence of Silica Fume Addition in the Long-Term Performance of Sustainable Cement Grouts for Micropiles Exposed to a Sulphate Aggressive Medium

PubMed Central

Esteban, María Dolores; Rodríguez, Raúl Rubén; Ibanco, Francisco José; Sánchez, Isidro

2017-01-01

At present, sustainability is of major importance in the cement industry, and the use of additions such as silica fume as clinker replacement contributes towards that goal. Special foundations, and particularly micropiles, are one of the most suitable areas for the use of sustainable cements. The aim of this research is to analyse the effects in the very long-term (for 600 days) produced by sulphate attack in the microstructure of grouts for micropiles in which OPC (ordinary Portland cement) has been replaced by 5% and 10% silica fume. This line of study is building on a previous work, where these effects were studied in slag and fly ash grouts. Grouts made using a commercial sulphate-resisting Portland cement were also studied. The non-destructive impedance spectroscopy technique, mercury intrusion porosimetry, and Wenner resistivity testing were used. Mass variation and the compressive strength have also been analysed. Apparently, impedance spectroscopy is the most suitable technique for studying sulphate attack development. According to the results obtained, grouts for micropiles with a content of silica fume up to 10% and exposed to an aggressive sulphate medium, have a similar or even better behaviour in the very long-term, compared to grouts prepared using sulphate-resisting Portland cement. PMID:28767078

Influence of Silica Fume Addition in the Long-Term Performance of Sustainable Cement Grouts for Micropiles Exposed to a Sulphate Aggressive Medium.

PubMed

Ortega, José Marcos; Esteban, María Dolores; Rodríguez, Raúl Rubén; Pastor, José Luis; Ibanco, Francisco José; Sánchez, Isidro; Climent, Miguel Ángel

2017-08-02

At present, sustainability is of major importance in the cement industry, and the use of additions such as silica fume as clinker replacement contributes towards that goal. Special foundations, and particularly micropiles, are one of the most suitable areas for the use of sustainable cements. The aim of this research is to analyse the effects in the very long-term (for 600 days) produced by sulphate attack in the microstructure of grouts for micropiles in which OPC (ordinary Portland cement) has been replaced by 5% and 10% silica fume. This line of study is building on a previous work, where these effects were studied in slag and fly ash grouts. Grouts made using a commercial sulphate-resisting Portland cement were also studied. The non-destructive impedance spectroscopy technique, mercury intrusion porosimetry, and Wenner resistivity testing were used. Mass variation and the compressive strength have also been analysed. Apparently, impedance spectroscopy is the most suitable technique for studying sulphate attack development. According to the results obtained, grouts for micropiles with a content of silica fume up to 10% and exposed to an aggressive sulphate medium, have a similar or even better behaviour in the very long-term, compared to grouts prepared using sulphate-resisting Portland cement.

Cementitious waste option scoping study report

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

Lee, A.E.; Taylor, D.D.

1998-02-01

A Settlement Agreement between the Department of Energy (DOE) and the State of Idaho mandates that all high-level radioactive waste (HLW) now stored at the Idaho Chemical Processing Plant (ICPP) on the Idaho National Engineering and Environmental Laboratory (INEEL) will be treated so that it is ready to be moved out of Idaho for disposal by a target date of 2035. This study investigates the nonseparations Cementitious Waste Option (CWO) as a means to achieve this goal. Under this option all liquid sodium-bearing waste (SBW) and existing HLW calcine would be recalcined with sucrose, grouted, canisterized, and interim stored asmore » a mixed-HLW for eventual preparation and shipment off-Site for disposal. The CWO waste would be transported to a Greater Confinement Disposal Facility (GCDF) located in the southwestern desert of the US on the Nevada Test Site (NTS). All transport preparation, shipment, and disposal facility activities are beyond the scope of this study. CWO waste processing, packaging, and interim storage would occur over a 5-year period between 2013 and 2017. Waste transport and disposal would occur during the same time period.« less

Application of landfill treatment approaches for stabilization of municipal solid waste.

PubMed

Bolyard, Stephanie C; Reinhart, Debra R

2016-09-01

This research sought to compare the effectiveness of three landfill enhanced treatment approaches aimed at removing releasable carbon and nitrogen after anaerobic landfilling including flushing with clean water (FB 1), leachate recirculation with ex-situ treatment (FB 2), and leachate recirculation with ex-situ treatment and in-situ aeration (FB 3). After extensive treatment of the waste in the FB scenarios, the overall solids and biodegradable fraction were reduced relative to the mature anaerobically treated waste. In terms of the overall degradation, aeration did not provide any advantage over flushing and anaerobic treatment. Flushing was the most effective approach at removing biodegradable components (i.e. cellulose and hemicellulose). Leachate quality improved for all FBs but through different mechanisms. A significant reduction in ammonia-nitrogen occurred in FB 1 and 3 due to flushing and aeration, respectively. The reduction of chemical oxygen demand (COD) in FB 1 was primarily due to flushing. Conversely, the reduction in COD in FBs 2 and 3 was due to oxidation and precipitation during Fenton's Reagent treatment. A mass balance on carbon and nitrogen revealed that a significant fraction still remained in the waste despite the additional treatment provided. Carbon was primarily converted biologically to CH4 and CO2 in the FBs or removed during treatment using Fenton's Reagent. The nitrogen removal occurred through leaching or biological conversion. These results show that under extensive treatment the waste and leachate characteristics did meet published stability values. The minimum stability values achieved were through flushing although FB 2 and 3 were able to improve leachate quality and solid waste characteristics but not to the same extent as FB 1. Copyright © 2016 Elsevier Ltd. All rights reserved.

EVALUATION USING AN ORGANOPHILIC CLAY TO CHEMICALLY STABILIZE WASTE CONTAINING ORGANIC COMPOUNDS

EPA Science Inventory

A modified clay (organophilic) was utilized to evaluate the potential for chemically stabilizing a waste containing organic compounds. hemical bonding between the binder and the contaminants was indicated. eachate testing also indicated strong binding. Copy available at NTIS as ...

Long-term anaerobic digestion of food waste stabilized by trace elements.

PubMed

Zhang, Lei; Jahng, Deokjin

2012-08-01

The purpose of this study was to examine if long-term anaerobic digestion of food waste in a semi-continuous single-stage reactor could be stabilized by supplementing trace elements. Contrary to the failure of anaerobic digestion of food waste alone, stable anaerobic digestion of food waste was achieved for 368 days by supplementing trace elements. Under the conditions of OLR (organic loading rates) of 2.19-6.64 g VS (volatile solid)/L day and 20-30 days of HRT (hydraulic retention time), a high methane yield (352-450 mL CH(4)/g VS(added)) was obtained, and no significant accumulation of volatile fatty acids was observed. The subsequent investigation on effects of individual trace elements (Co, Fe, Mo and Ni) showed that iron was essential for maintaining stable methane production. These results proved that the food waste used in this study was deficient in trace elements. Copyright © 2012. Published by Elsevier Ltd.

Method of waste stabilization with dewatered chemically bonded phosphate ceramics

DOEpatents

Wagh, Arun; Maloney, Martin D.

2010-06-29

A method of stabilizing a waste in a chemically bonded phosphate ceramic (CBPC). The method consists of preparing a slurry including the waste, water, an oxide binder, and a phosphate binder. The slurry is then allowed to cure to a solid, hydrated CBPC matrix. Next, bound water within the solid, hydrated CBPC matrix is removed. Typically, the bound water is removed by applying heat to the cured CBPC matrix. Preferably, the quantity of heat applied to the cured CBPC matrix is sufficient to drive off water bound within the hydrated CBPC matrix, but not to volatalize other non-water components of the matrix, such as metals and radioactive components. Typically, a temperature range of between 100.degree. C.-200.degree. C. will be sufficient. In another embodiment of the invention wherein the waste and water have been mixed prior to the preparation of the slurry, a select amount of water may be evaporated from the waste and water mixture prior to preparation of the slurry. Another aspect of the invention is a direct anyhydrous CBPC fabrication method wherein water is removed from the slurry by heating and mixing the slurry while allowing the slurry to cure. Additional aspects of the invention are ceramic matrix waste forms prepared by the methods disclosed above.

In-situ, time resolved monitoring of uranium in BFS:OPC grout. Part 2: Corrosion in water.

PubMed

Stitt, C A; Paraskevoulakos, C; Banos, A; Harker, N J; Hallam, K R; Pullin, H; Davenport, A; Street, S; Scott, T B

2018-06-18

To reflect potential conditions in a geological disposal facility, uranium was encapsulated in grout and submersed in de-ionised water for time periods between 2-47 weeks. Synchrotron X-ray Powder Diffraction and X-ray Tomography were used to identify the dominant corrosion products and measure their dimensions. Uranium dioxide was observed as the dominant corrosion product and time dependent thickness measurements were used to calculate oxidation rates. The effectiveness of physical and chemical grout properties to uranium corrosion and mobilisation is discussed and Inductively Coupled Plasma Mass Spectrometry was used to measure 238 U (aq) content in the residual water of several samples.

Long-term anaerobic digestion of food waste stabilized by trace elements

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

Zhang Lei, E-mail: wxzyfx@yahoo.com; Jahng, Deokjin, E-mail: djahng@mju.ac.kr

Highlights: Black-Right-Pointing-Pointer Korean food waste was found to contain low level of trace elements. Black-Right-Pointing-Pointer Stable anaerobic digestion of food waste was achieved by adding trace elements. Black-Right-Pointing-Pointer Iron played an important role in anaerobic digestion of food waste. Black-Right-Pointing-Pointer Cobalt addition further enhanced the process performance in the presence of iron. - Abstract: The purpose of this study was to examine if long-term anaerobic digestion of food waste in a semi-continuous single-stage reactor could be stabilized by supplementing trace elements. Contrary to the failure of anaerobic digestion of food waste alone, stable anaerobic digestion of food waste was achievedmore » for 368 days by supplementing trace elements. Under the conditions of OLR (organic loading rates) of 2.19-6.64 g VS (volatile solid)/L day and 20-30 days of HRT (hydraulic retention time), a high methane yield (352-450 mL CH{sub 4}/g VS{sub added}) was obtained, and no significant accumulation of volatile fatty acids was observed. The subsequent investigation on effects of individual trace elements (Co, Fe, Mo and Ni) showed that iron was essential for maintaining stable methane production. These results proved that the food waste used in this study was deficient in trace elements.« less

In-situ, time resolved monitoring of uranium in BFS:OPC grout. Part 1: Corrosion in water vapour.

PubMed

Stitt, C A; Paraskevoulakos, C; Banos, A; Harker, N J; Hallam, K R; Davenport, A; Street, S; Scott, T B

2017-08-11

Uranium encapsulated in grout was exposed to water vapour for extended periods of time. Through synchrotron x-ray powder diffraction and tomography measurements, uranium dioxide was determined the dominant corrosion product over a 50-week time period. The oxide growth rate initiated rapidly, with rates comparable to the U + H 2 O reaction. Over time, the reaction rate decreased and eventually plateaued to a rate similar to the U + H 2 O + O 2 reaction. This behaviour was not attributed to oxygen ingress, but instead the decreasing permeability of the grout, limiting oxidising species access to the metal surface.

Integrated waste management as a climate change stabilization wedge.

PubMed

Bahor, Brian; Van Brunt, Michael; Stovall, Jeff; Blue, Katherine

2009-11-01

Anthropogenic sources of greenhouse gas emissions are known to contribute to global increases in greenhouse gas concentrations and are widely believed to contribute to climate change. A reference carbon dioxide concentration of 383 ppm for 2007 is projected to increase to a nominal 500 ppm in less than 50 years according to business as usual models. This concentration change is equivalent to an increase of 7 billion tonnes of carbon per year (7 Gt C year(-1)). The concept of a stabilization wedge was introduced by Pacala and Socolow (Science, 305, 968-972, 2004) to break the 7 Gt C year(- 1) into more manageable 1 Gt C year(- 1) reductions that would be achievable with current technology. A total of fifteen possible 'wedges' were identified; however, an integrated municipal solid waste (MSW) management system based on the European Union's waste management hierarchy was not evaluated as a wedge. This analysis demonstrates that if the tonnage of MSW is allocated to recycling, waste to energy and landfilling in descending order in lieu of existing 'business-as-usual' practices with each option using modern technology and best practices, the system would reduce greenhouse gas emissions by more than 1 Gt C year( -1). This integrated waste management system reduces CO(2) by displacing fossil electrical generation and avoiding manufacturing energy consumption and methane emissions from landfills.

Vermicomposting of food waste: assessing the stability and maturity

PubMed Central

2012-01-01

The vermicompost using earthworms (Eisenia Fetida) was produced from food waste and chemical parameters (EC, pH, carbon to nitrogen contents (C/N)) and germination bioassay was examined in order to assess the stability and maturity indicators during the vermicomposting process. The seed used in the germination bioassay was cress. The ranges of EC, pH, C/N and germination index were 7.5-4.9 mS/cm, 5.6-7.53, 30.13-14.32% and 12.8-58.4%, respectively. The germination index (GI) value revealed that vermicompost rendered as moderate phytotoxic to cress seed. Pearson correlation coefficient was used to evaluate the relationship between the parameters. High statistically significant correlation coefficient was calculated between the GI value and EC in the vermicompost at the 99% confidence level. The C/N value showed that the vermicompost was stable. As a result of these observations, stability test alone, was not able to ensure high vermicompost quality. Therefore, it appears that determining vermicompost quality requires a simultaneous use of maturity and stability tests. PMID:23369642

77 FR 69508 - Inservice Inspection of Prestressed Concrete Containment Structures With Grouted Tendons

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-19

... real-time, multiple-strategy approach (i.e., appropriate grout design and installation, installed... is available in ADAMS) is provided the first time that a document is referenced. Revision 2 of... ``Regulatory Guide'' series. This series was developed to describe and make available to the public information...

Anchorage performance of a high-pressure pre-tightening resin anchor with a compressed grouting body

PubMed Central

Tian, Jiansheng; Hu, Li

2017-01-01

Supports for deep mine roadways located in soft surrounding rock face several problems: difficulty in applying pre-tightening force, low bearing capacity, and poor initial support. To solve these problems, this study proposes a high-pressure pre-tightening resin anchor with a compressed grouting body for use in soft and fractured rock surrounding a deep roadway. Using model experiments, we analyzed the anchorage performance of the proposed anchor and a conventional tensile-type anchor for three different values of the elastic modulus of the surrounding rock. The results showed that regardless of the surrounding rock type, the peak micro-strain (642–541) and displacement (6.09–6.5 mm) at the pull-out end of the proposed anchor were always smaller than the peak micro-strain (1433–1105) and displacement (8.77–9.2 mm) at the pull-out end of the conventional anchor. Furthermore, as the anchor’s pre-tightening force increased from 20 kN to 120 kN, the anchor’s strain remained concentrated over a length of 0.4 m from the bearing end. Compared with conventional tensile-type anchors, the proposed high-pressure pre-tightening resin anchor with a compressed grouting body has a higher ultimate bearing capacity, allows the grouting length to be decreased to 0.4 m, and provides initial support resistance. PMID:28196084

Process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Colombo, Peter; Kalb, Paul D.; Heiser, III, John H.

1997-11-14

The present invention provides a method for encapsulating and stabilizing radioactive, hazardous and mixed wastes in a modified sulfur cement composition. The waste may be incinerator fly ash or bottom ash including radioactive contaminants, toxic metal salts and other wastes commonly found in refuse. The process may use glass fibers mixed into the composition to improve the tensile strength and a low concentration of anhydrous sodium sulfide to reduce toxic metal solubility. The present invention preferably includes a method for encapsulating radioactive, hazardous and mixed wastes by combining substantially anhydrous wastes, molten modified sulfur cement, preferably glass fibers, as well as anhydrous sodium sulfide or calcium hydroxide or sodium hydroxide in a heated double-planetary orbital mixer. The modified sulfur cement is preheated to about 135.degree..+-.5.degree. C., then the remaining substantially dry components are added and mixed to homogeneity. The homogeneous molten mixture is poured or extruded into a suitable mold. The mold is allowed to cool, while the mixture hardens, thereby immobilizing and encapsulating the contaminants present in the ash.

Colour vision and light sensitivity in tunnel workers previously exposed to acrylamide and N-methylolacrylamide containing grouting agents.

PubMed

Goffeng, Lars Ole; Kjuus, Helge; Heier, Mona Skard; Alvestrand, Monica; Ulvestad, Bente; Skaug, Vidar

2008-01-01

The aim of the study was to examine possible persisting visual system effects in tunnel workers previously exposed to acrylamide and N-methylolacrylamide during grouting work. Visual field light sensitivity threshold and colour vision has been examined among 44 tunnel workers 2-10 years after exposure to acrylamide and N-methylolacrylamide containing grouting agents. Forty-four tunnel workers not involved in grouting operations served as control group. Information on exposure and background variables was obtained for all participants from a questionnaire. Visual light sensitivity threshold was measured using Humphrey Visual Field Static Perimeter 740, program 30-2 Fastpack, with red stimuli on white background, and colour vision, using Lanthony D-15 Desaturated Color test. Based on D-15d test results, colour confusion index (CCI), and a severity index (C-index) was calculated. The exposed group had a significantly higher threshold for detecting single stimuli in all parts of the inner 30 degrees of the visual field compared to the control group. The foveal threshold group difference was 1.4 dB (p=0.002) (mean value, both eyes). On the Lanthony 15 Hue Desaturated test, the exposed subjects made more errors in sorting blue colours, and a statistically significant increase in C-index was observed. Surrogate measures for duration and intensity of exposure gave no further improvement of the model. The results indicate slightly reduced light sensitivity and reduced colour discrimination among the exposed subjects compared to the controls. The findings may be due to previous exposure to acrylamide containing grouts among the tunnel workers.

Oxidative Stability of Tc(I) Tricarbonyl Species Relevant to the Hanford Tank Waste

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

Chatterjee, Sayandev; Hall, Gabriel B.; Levitskaia, Tatiana G.

Technetium (Tc), which exists predominately in the liquid supernatant and salt cake fractions of the nuclear tank waste stored at the U.S. DOE Hanford Site, is one of the most difficult contaminants to dispose of and/or remediate. In the strongly alkaline environments prevalent in the tank waste, its dominant chemical form is pertechnetate (TcO 4 -, oxidation state +7). However, based on experimentation to-date, a significant fraction of the soluble Tc cannot be effectively separated from the wastes and may be present as a non-pertechnetate species. The presence of a non pertechnetate species significantly complicates disposition of low-activity waste (LAW),more » and the development of methods to either convert them to pertechnetate or to separate the non-pertechnetate species directly is needed. The challenge is the uncertainty regarding the nature and stability of the alkaline-soluble, low-valence, non pertechnetate species in the liquid tank waste. One objective of the Tc management project is to address this knowledge gap. This fiscal year (FY) 2015 report summarizes experimental work exploring the oxidative stability of model low-valence Tc(I) tricarbonyl species, derived from the [Tc(CO) 3] + moiety. These compounds are of interest due to their implied presence in several Hanford tank waste supernatants. Work in part was initiated in FY 2014, and a series of samples containing non-pertechnetate Tc generated ex situ or in situ in pseudo-Hanford tank supernatant simulant solutions was prepared and monitored for oxidation to Tc(VII) (Levitskaia et al. 2014). This experimentation continued in FY 2015, and new series of samples containing Tc(I) as [Tc(CO) 3] +•Ligand was tested. The monitoring method used for these studies was a combination of 99Tc NMR and EPR spectroscopies.« less

HIGH TEMPERATURE TREATMENT OF INTERMEDIATE-LEVEL RADIOACTIVE WASTES - SIA RADON EXPERIENCE

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

Sobolev, I.A.; Dmitriev, S.A.; Lifanov, F.A.

2003-02-27

This review describes high temperature methods of low- and intermediate-level radioactive waste (LILW) treatment currently used at SIA Radon. Solid and liquid organic and mixed organic and inorganic wastes are subjected to plasma heating in a shaft furnace with formation of stable leach resistant slag suitable for disposal in near-surface repositories. Liquid inorganic radioactive waste is vitrified in a cold crucible based plant with borosilicate glass productivity up to 75 kg/h. Radioactive silts from settlers are heat-treated at 500-700 0C in electric furnace forming cake following by cake crushing, charging into 200 L barrels and soaking with cement grout. Variousmore » thermochemical technologies for decontamination of metallic, asphalt, and concrete surfaces, treatment of organic wastes (spent ion-exchange resins, polymers, medical and biological wastes), batch vitrification of incinerator ashes, calcines, spent inorganic sorbents, contaminated soil, treatment of carbon containing 14C nuclide, reactor graphite, lubricants have been developed and implemented.« less

Guidelines for Sampling, Assessing, and Restoring Defective Grout in Prestressed Concrete Bridge Post-Tensioning Ducts

DOT National Transportation Integrated Search

2013-05-01

This document is a technical summary of the Federal Highway Administration report, "Guidelines for Sampling, Assessing, and Restoring Defective Grout in Prestressed Concrete Bridge Post-Tensioning Ducts" (FHWA-HRT-13-028). The objectives of this stud...

Guidelines for Sampling, Assessing, and Restoring Defective Grout in Prestressed Concrete Bridge Post-Tensioning Ducts

DOT National Transportation Integrated Search

2013-10-01

A significant proportion of the United States bridge inventory is based on bonded post-tensioned (PT) concrete construction. An important aspect of maintaining corrosion protection of these PT systems is assuring that tendon ducts are properly groute...

Waste Receiving and Processing Facility Module 2A: Advanced Conceptual Design Report. Volume 3A

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

Not Available

Objective of this document is to provide descriptions of all WRAP 2A feed streams, including physical and chemical attributes, and describe the pathway that was used to select data for volume estimates. WRAP 2A is being designed for nonthermal treatment of contact-handled mixed low-level waste Category 1 and 3. It is based on immobilization and encapsulation treatment using grout or polymer.

Guidelines for sampling, assessing, and restoring defective grout in prestressed concrete bridge post-tensioning ducts.

DOT National Transportation Integrated Search

2013-10-01

"A significant proportion of the U.S. bridge inventory is based on bonded post-tensioned (PT) concrete construction. An : important aspect of maintaining corrosion protection of these PT systems is assuring that tendon ducts are properly grouted : wi...

ICPP tank farm closure study. Volume 2: Engineering design files

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

NONE

1998-02-01

Volume 2 contains the following topical sections: Tank farm heel flushing/pH adjustment; Grouting experiments for immobilization of tank farm heel; Savannah River high level waste tank 20 closure; Tank farm closure information; Clean closure of tank farm; Remediation issues; Remote demolition techniques; Decision concerning EIS for debris treatment facility; CERCLA/RCRA issues; Area of contamination determination; Containment building of debris treatment facility; Double containment issues; Characterization costs; Packaging and disposal options for the waste resulting from the total removal of the tank farm; Take-off calculations for the total removal of soils and structures at the tank farm; Vessel off-gas systems; Jet-groutedmore » polymer and subsurface walls; Exposure calculations for total removal of tank farm; Recommended instrumentation during retrieval operations; High level waste tank concrete encasement evaluation; Recommended heavy equipment and sizing equipment for total removal activities; Tank buoyancy constraints; Grout and concrete formulas for tank heel solidification; Tank heel pH requirements; Tank cooling water; Evaluation of conservatism of vehicle loading on vaults; Typical vault dimensions and approximately tank and vault void volumes; Radiological concerns for temporary vessel off-gas system; Flushing calculations for tank heels; Grout lift depth analysis; Decontamination solution for waste transfer piping; Grout lift determination for filling tank and vault voids; sprung structure vendor data; Grout flow properties through a 2--4 inch pipe; Tank farm load limitations; NRC low level waste grout; Project data sheet calculations; Dose rates for tank farm closure tasks; Exposure and shielding calculations for grout lines; TFF radionuclide release rates; Documentation of the clean closure of a system with listed waste discharge; and Documentation of the ORNL method of radionuclide concentrations in tanks.« less

EVALUATION OF CHEMICALLY BONDED PHOSPHATE CERAMICS FOR MERCURY STABILIZATION OF A MIXED SYNTHETIC WASTE

EPA Science Inventory

This experimental study was conducted to evaluate the stabilization and encapsulation technique developed by Argonne National Laboratory, called the Chemically Bonded Phosphate Ceramics technology for Hg- and HgCl₂-contaminated synthetic waste materials. Leachability ...

Minimizing the impact on water quality of placing grout underwater to repair bridge scour damage.

DOT National Transportation Integrated Search

2003-01-01

The Virginia Department of Transportation (VDOT) has routinely used what is commonly referred to as tremie concrete (concrete or grout placed underwater by way of pumping through a metal tremie pipe) to repair bridge substructure and scour damage. VD...

Injectable barriers for waste isolation

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

Persoff, P.; Finsterle, S.; Moridis, G.J.

In this paper the authors report laboratory work and numerical simulation done in support of development and demonstration of injectable barriers formed from either of two fluids: colloidal silica or polysiloxane. Two principal problems addressed here are control of gel time and control of plume emplacement in the vadose zone. Gel time must be controlled so that the viscosity of the barrier fluid remains low long enough to inject the barrier, but increases soon enough to gel the barrier in place. During injection, the viscosity must be low enough to avoid high injection pressures which could uplift or fracture themore » formation. To test the grout gel time in the soil, the injection pressure was monitored as grouts were injected into sandpacks. When grout is injected into the vadose zone, it slumps under the influence of gravity, and redistributes due to capillary forces as it gels. The authors have developed a new module for the reservoir simulator TOUGH2 to model grout injection into the vadose zone, taking into account the increase of liquid viscosity as a function of gel concentration and time. They have also developed a model to calculate soil properties after complete solidification of the grout. The numerical model has been used to design and analyze laboratory experiments and field pilot tests. The authors present the results of computer simulations of grout injection, redistribution, and solidification.« less

[Effects of stabilization treatment on migration and transformation of heavy metals in mineral waste residues].

PubMed

Zhao, Shu-Hua; Chen, Zhi-Liang; Zhang, Tai-Ping; Pan, Wei-Bin; Peng, Xiao-Chun; Che, Rong; Ou, Ying-Juan; Lei, Guo-Jian; Zhou, Ding

2014-04-01

Different forms of heavy metals in soil will produce different environmental effects, and will directly influence the toxicity, migration and bioavailability of heavy metals. This study used lime, fly ash, dried sludge, peanut shells as stabilizers in the treatment of heavy metals in mineral waste residues. Morphological analyses of heavy metal, leaching experiments, potted plant experiments were carried out to analyze the migration and transformation of heavy metals. The results showed that after adding stabilizers, the pH of the acidic mineral waste residues increased to more than neutral, and the organic matter content increased significantly. The main existing forms of As, Pb, and Zn in the mineral waste residues were the residual. The contents of exchangeable and organic matter-bound As decreased by 65.6% and 87.7% respectively after adding fly ash, dried sludge and peanut shells. Adding lime, fly ash and peanut shells promoted the transformation of As from the Fe-Mn oxide-bound to the carbonate-bound, and adding lime and fly ash promoted the transformation of Pb and Zn from the exchangeable, Fe-Mn oxide-bound, organic matter-bound to the residual. After the early stage of the stabilization treatment, the contents of As, Pb and Zn in the leachate had varying degrees of decline, and adding peanut shells could reduce the contents of As, Pb and Zn in the leachate further. Among them, the content of As decreased most significantly after treatment with fly ash, dried sludge and peanut shells, with a decline of 57.4%. After treatment with lime, fly ash and peanut shells, the content of Zn decreased most significantly, by 24.9%. The addition of stabilizers was advantageous to the germination and growth of plants. The combination of fly ash, dried sludge and peanut shell produced the best effect, and the Vetiveria zizanioides germination rate reached 76% in the treated wasted mineral residues.

Long-Term Behaviour of Fly Ash and Slag Cement Grouts for Micropiles Exposed to a Sulphate Aggressive Medium.

PubMed

Ortega, José Marcos; Esteban, María Dolores; Rodríguez, Raúl Rubén; Pastor, José Luis; Ibanco, Francisco José; Sánchez, Isidro; Climent, Miguel Ángel

2017-05-30

Nowadays, one of the most popular ways to get a more sustainable cement industry is using additions as cement replacement. However, there are many civil engineering applications in which the use of sustainable cements is not extended yet, such as special foundations, and particularly micropiles, even though the standards do not restrict the cement type to use. These elements are frequently exposed to the sulphates present in soils. The purpose of this research is to study the effects in the very long-term (until 600 days) of sulphate attack in the microstructure of micropiles grouts, prepared with ordinary Portland cement, fly ash and slag commercial cements, continuing a previous work, in which these effects were studied in the short-term. The microstructure changes have been analysed with the non-destructive impedance spectroscopy technique, mercury intrusion porosimetry and the "Wenner" resistivity test. The mass variation and the compressive strength have also been studied. The impedance spectroscopy has been the most sensitive technique for following the sulphate attack process. Considering the results obtained, micropiles grouts with slag and fly ash, exposed to an aggressive medium with high content of sulphates, have shown good behaviour in the very long-term (600 days) compared to grouts made with OPC.

Long-Term Behaviour of Fly Ash and Slag Cement Grouts for Micropiles Exposed to a Sulphate Aggressive Medium

PubMed Central

Ortega, José Marcos; Esteban, María Dolores; Rodríguez, Raúl Rubén; Pastor, José Luis; Ibanco, Francisco José; Sánchez, Isidro; Climent, Miguel Ángel

2017-01-01

Nowadays, one of the most popular ways to get a more sustainable cement industry is using additions as cement replacement. However, there are many civil engineering applications in which the use of sustainable cements is not extended yet, such as special foundations, and particularly micropiles, even though the standards do not restrict the cement type to use. These elements are frequently exposed to the sulphates present in soils. The purpose of this research is to study the effects in the very long-term (until 600 days) of sulphate attack in the microstructure of micropiles grouts, prepared with ordinary Portland cement, fly ash and slag commercial cements, continuing a previous work, in which these effects were studied in the short-term. The microstructure changes have been analysed with the non-destructive impedance spectroscopy technique, mercury intrusion porosimetry and the “Wenner” resistivity test. The mass variation and the compressive strength have also been studied. The impedance spectroscopy has been the most sensitive technique for following the sulphate attack process. Considering the results obtained, micropiles grouts with slag and fly ash, exposed to an aggressive medium with high content of sulphates, have shown good behaviour in the very long-term (600 days) compared to grouts made with OPC. PMID:28772958

Use of cement-fly ash-based stabilization techniques for the treatment of waste containing aromatic contaminants

NASA Astrophysics Data System (ADS)

Banaszkiewicz, Kamil; Marcinkowski, Tadeusz

2017-11-01

Research on evaluation of evaporation rate of volatile organic compounds from soil beds during processing is presented. For the experiment, soil samples were prepared with the same amounts of benzene and stabilized using a mixture of CEMI 42.5R cement and fly ash from pit-coal combustion. Solidification of soils contaminated with BTEX hydrocarbons using hydraulic binders involves a risk of releasing vapours of these compounds during homogenization of waste with stabilizing mixture introduced and its dilution with water. The primary purposes of the research were: analysis of benzene volume emitted from soil during stabilization/solidification process and characterization of factors that may negatively affect the quality of measurements/the course of stabilization process. Analysis of benzene emission intensity during the process was based on concentration (C6H6) values, recorded with flame-ionization detector above the surface of reacting mixture. At the same time, gaseous contaminants emitted during waste stabilization were passed through pipes filled with activated carbon (SCK, Anasorb CSC). Benzene vapours adsorbed on activated carbon were subjected to analysis using gas chromatograph Varian 450-GC. Evaporation characteristics of benzene during processing contaminated soils revealed the stages creating the highest danger to workers' health, as well as a need for actions connected with modification of technological line.

Installation and use of epoxy-grouted rock anchors for skyline logging in southeast Alaska.

Treesearch

W.L. Schroeder; D.N. Swanston

1992-01-01

Field tests of the load-carrying capacity of epoxy-grouted rock anchors in poor quality bedrock on Wrangel Island in southeast Alaska demonstrated the effectiveness of rock anchors as substitutes for stump anchors for logging system guylines. Ultimate capacity depends mainly on rock hardness or strength and length of the imbedded anchor.

Soil Improvement By Jet Grout Method And Geogrid Against Liquefaction: Example Of Samsun-Tekkeköy

NASA Astrophysics Data System (ADS)

Öztürk, Seda; Banu İkizler, S.; Şadoǧlu, Erol; Dadaşbilge, Ozan; Angın, Zekai

2017-04-01

scenarios of earthquakes with 6.0, 6.5, 7.0 and 7.2 magnitudes. As a result of the analyses made, it has been deemed necessary to improve the soil in order to prevent or reduce the liquefaction effects which may occur in a possible earthquake due to the presence of liquefaction potential in the research area. For this purpose, jet grouting method and geogrid fill system, which are used widely in Turkey, have been chosen as appropriate improvement methods. Geogrids are strong in tension so they are commonly used to reinforce subsoils below foundations. Additionally, jet grouting method provides high bearing capacity; it is solution to the settlement problems, it can be applied to almost any kind of soil and it has a short production period. Within this scope, optimal solution was obtained with 616 pieces of 8 m and 12 m jet grout columns with the diameter of 0.65 m and with geogrid mechanical fillings laid on jet grout columns. Thus, not only the risk of liquefaction was eliminated but also an improvement of more than 3 times of the bearing capacity of the foundation was acquired. In addition, the required quality control tests were carried out for the jet grout columns built in the research area and no adverse effects were observed. Key words: Liquefaction, soil improvement, jet grouting, geogrid

Integration of National Laboratory and Low-Activity Waste Pre-Treatment System Technology Service Providers - 16435

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

Subramanian, Karthik H.; Thien, Michael G.; Wellman, Dawn M.

The National Laboratories are a critical partner and provide expertise in numerous aspects of the successful execution of the Direct-Feed Low Activity Waste Program. The National Laboratories are maturing the technologies of the Low-Activity Waste Pre-Treatment System (LAWPS) consistent with DOE Order 413.3B “Program and Project Management for the Acquisition of Capital Assets” expectations. The National Laboratories continue to mature waste forms, i.e. glass and secondary waste grout, for formulations and predictions of long-term performance as inputs to performance assessments. The working processes with the National Laboratories have been developed in procurements, communications, and reporting to support the necessary delivery-basedmore » technology support. The relationship continues to evolve from planning and technology development to support of ongoing operations and integration of multiple highly coordinated facilities.« less

Changes in soil aggregate stability under different irrigation doses of waste water

NASA Astrophysics Data System (ADS)

Morugán, Alicia; García-Orenes, Fuensanta; Mataix-Solera, Jorge; Arcenegui, Victoria; Bárcenas, Gema

2010-05-01

Freshwater availability and soil degradation are two of the most important environmental problems in the Mediterranean area acerbated by incorrect agricultural use of irrigation in which organic matter is not correctly managed, the use of low quality water for irrigation, and the inefficiency of dose irrigation. For these reasons strategies for saving water and for the restoration of the mean properties of soil are necessary. The use of treated waste water for the irrigation of agricultural land could be a good solution to these problems, as it reduces the utilization of fresh water and could potentially improve key soil properties. In this work we have been studying, for more than three years, the effects on soil properties of different doses of irrigation with waste water. Here we show the results on aggregate stability. The study is located in an agricultural area at Biar (Alicante, SE of Spain), with a crop of grape (Vitis labrusca). Three types of waters are being used in the irrigation of the soil: fresh water (control) (TC), and treated waste water from secondary (T2) and tertiary treatment (T3). Three different doses of irrigation have been applied to fit the efficiency of the irrigation to the crop and soil type: D10 (10 L m-2 every week during 17 months), D50 (50 L m-2 every fifteen days during 14 moths) and D30 (30 L m-2 every week during 6 months up to present day). The results showed a clear decrease of aggregate stability during the period we used the second dose (D50) independent of the type of water used. That dose of irrigation and frequency produced strong wetting and drying cycles (WD) in the soil, and this is suspected to be the main factor responsible for the results. When we changed the dose of irrigation to D30, reducing the quantity per event and increasing the frequency, the soil aggregate stability started to improve. This dose avoids strong drying periods between irrigation events and the aggregate stability is confirmed to be slowly

Composting technology in waste stabilization: On the methods, challenges and future prospects.

PubMed

Onwosi, Chukwudi O; Igbokwe, Victor C; Odimba, Joyce N; Eke, Ifeanyichukwu E; Nwankwoala, Mary O; Iroh, Ikemdinachi N; Ezeogu, Lewis I

2017-04-01

Composting technology has become invaluable in stabilization of municipal waste due to its environmental compatibility. In this review, different types of composting methods reportedly applied in waste management were explored. Further to that, the major factors such as temperature, pH, C/N ratio, moisture, particle size that have been considered relevant in the monitoring of the composting process were elucidated. Relevant strategies to improve and optimize process effectiveness were also addressed. However, during composting, some challenges such as leachate generation, gas emission and lack of uniformity in assessing maturity indices are imminent. Here in, these challenges were properly addressed and some strategies towards ameliorating them were proffered. Finally, we highlighted some recent technologies that could improve composting. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ultrasonic waste activated sludge disintegration for improving anaerobic stabilization.

PubMed

Tiehm, A; Nickel, K; Zellhorn, M; Neis, U

2001-06-01

The pretreatment of waste activated sludge by ultrasonic disintegration was studied in order to improve the anaerobic sludge stabilization. The ultrasound frequency was varied within a range from 41 to 3217 kHz. The impact of different ultrasound intensities and treatment times was examined. Sludge disintegration was most significant at low frequencies. Low-frequency ultrasound creates large cavitation bubbles which upon collapse initiate powerful jet streams exerting strong shear forces in the liquid. The decreasing sludge disintegration efficiency observed at higher frequencies was attributed to smaller cavitation bubbles which do not allow the initiation of such strong shear forces. Short sonication times resulted in sludge floc deagglomeration without the destruction of bacteria cells. Longer sonication brought about the break-up of cell walls, the sludge solids were distintegrated and dissolved organic compounds were released. The anaerobic digestion of waste activated sludge following ultrasonic pretreatment causing microbial cell lysis was significantly improved. There was an increase in the volatile solids degradation as well as an increase in the biogas production. The increase in digestion efficiency was proportional to the degree of sludge disintegration. To a lesser degree the deagglomeration of sludge flocs also augmented the anaerobic volatile solids degradation.

Optical characteristics of waste stabilization ponds: recommendations for monitoring.

PubMed

Davies-Colley, R J; Craggs, R J; Park, J; Nagels, J W

2005-01-01

The optical character of waste stabilization ponds (WSPs) is of concern for several reasons. Algal photosynthesis, which produces oxygen for waste oxidation in WSPs, is influenced by attenuation of sunlight in ponds. Disinfection in WSPs is influenced by optical characteristics because solar UV exposure usually dominates inactivation. The optical nature of WSPs effluent also affects assimilation by receiving waters. Despite the importance of light behaviour in WSPs, few studies have been made of their optical characteristics. We discuss simple optical measures suitable for routine monitoring of WSPs (including at sites remote from laboratories): optical density of filtrates - an index of dissolved coloured organic (humic) matter, visual clarity - to provide an estimate of the beam attenuation coefficient (a fundamental quantity needed for optical modelling) colour (hue) - as an indicator of general WSP 'condition' and irradiance attenuation quantifying depth of light penetration. The value of optical characterisation of WSPs is illustrated with reference to optical data for WSPs in NZ (including high-rate algal ponds) treating dairy cattle wastewater versus domestic sewage. We encourage increased research on optical characteristics of WSPs and the incorporation of optical measures in monitoring and modelling of WSP performance.

Small hazardous waste generators in developing countries: use of stabilization/solidification process as an economic tool for metal wastewater treatment and appropriate sludge disposal.

PubMed

Silva, Marcos A R; Mater, Luciana; Souza-Sierra, Maria M; Corrêa, Albertina X R; Sperb, Rafael; Radetski, Claudemir M

2007-08-25

The aim of this study was to propose a profitable destination for an industrial sludge that can cover the wastewater treatment costs of small waste generators. Optimized stabilization/solidification technology was used to treat hazardous waste from an electroplating industry that is currently released untreated to the environment. The stabilized/solidified (S/S) waste product was used as a raw material to build concrete blocks, to be sold as pavement blocks or used in roadbeds and/or parking lots. The quality of the blocks containing a mixture of cement, lime, clay and waste was evaluated by means of leaching and solubility tests according to the current Brazilian waste regulations. Results showed very low metal leachability and solubility of the block constituents, indicating a low environmental impact. Concerning economic benefits from the S/S process and reuse of the resultant product, the cost of untreated heavy metal-containing sludge disposal to landfill is usually on the order of US$ 150-200 per tonne of waste, while 1tonne of concrete roadbed blocks (with 25% of S/S waste constitution) has a value of around US$ 100. The results of this work showed that the cement, clay and lime-based process of stabilization/solidification of hazardous waste sludge is sufficiently effective and economically viable to stimulate the treatment of wastewater from small industrial waste generators.

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.

Concrete and cement composites used for radioactive waste deposition.

PubMed

Koťátková, Jaroslava; Zatloukal, Jan; Reiterman, Pavel; Kolář, Karel

2017-11-01

This review article presents the current state-of-knowledge of the use of cementitious materials for radioactive waste disposal. An overview of radwaste management processes with respect to the classification of the waste type is given. The application of cementitious materials for waste disposal is divided into two main lines: i) as a matrix for direct immobilization of treated waste form; and ii) as an engineered barrier of secondary protection in the form of concrete or grout. In the first part the immobilization mechanisms of the waste by cement hydration products is briefly described and an up-to date knowledge about the performance of different cementitious materials is given, including both traditional cements and alternative binder systems. The advantages, disadvantages as well as gaps in the base of information in relation to individual materials are stated. The following part of the article is aimed at description of multi-barrier systems for intermediate level waste repositories. It provides examples of proposed concepts by countries with advanced waste management programmes. In the paper summary, the good knowledge of the material durability due to its vast experience from civil engineering is highlighted however with the urge for specific approach during design and construction of a repository in terms of stringent safety requirements. Copyright © 2017 Elsevier Ltd. All rights reserved.

Grouted pile to sleeves connections: Design provisions for the new ISO Standard for offshore structures

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

Harwood, R.G.; Billington, C.J.; Buitrago, J.

1996-12-01

A Technical Core Group (TCG) was set up in March 1994 to review the design practice provisions for grouted pile to sleeve connections, mechanical connections and repairs as part of the international harmonization process for the new ISO Standard, ISO 13819-2, Petroleum and Natural Gas Industries--Offshore Structures, Part 2: Fixed Steel Structures. This paper provides an overview of the development of the proposed new design provisions for grouted connections including, the gathering and screening of the data, the evolution of the design formulae, and the evaluation of the resistance factor. Detailed comparisons of the new formulae with current design practicemore » (API, HSE and DnV) are also included. In the development of the new provisions the TCG has been given access to the largest database ever assembled on this topic. This database includes all the major testing programs performed over the last 20 years, and recent UK and Norwegian research projects not previously reported. The limitations in the database are discussed and the areas where future research would be of benefit are highlighted.« less

CASE STUDY: IN-SITU SOLIDIFICATION/STABILIZATION OF HAZARDOUS ACID WASTE OIL SLUDGE AND LESSONS LEARNED

EPA Science Inventory

The South 8th Street site contained a 2.5 acre oily sludge pit with very low pH waste produced by oil recycling activities. This sludge was treated using in-situ solidification/stabilization technology applied by deep soil mixing augers. The problems encountered, solutions develo...

Oxygen respirometry to assess stability and maturity of composted municipal solid waste

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

Iannotti, D.A.; Grebus, M.E.; Toth, B.L.

1994-11-01

The stability and maturity of compost prepared from municipal solid waste (MSW) at a full-scale composting plant was assessed through chemical, physical, and biological assays. Respiration bioassays used to determine stability (O{sub 2} and CO{sub 2} respirometry) were sensitive to process control problems at the composting plant and indicated increasing stability with time. Radish (Raphanus sativus L.) and ryegrass (Lolium perenne L.) growth bioassays revealed that immature compost samples inhibited growth. Growth of ryegrass in potting mix prepared with cured compost not amended with fertilizer was enhanced as compared to a pest control. Garden cress (Lepidium sativum L.) seed germination,more » used as an indicator of phytotoxicity, revealed inhibition of germination at all compost maturity levels. The phytotoxicity was though to be salt-related. Spearman rank-order correlations demonstrated that O{sub 2} respirometry, water-soluble organic C, and the water extract organic C to organic N ratio, significantly correlated with compost age and best indicated an acceptable level of stability. Oxygen respirometry also best predicted the potential for ryegrass growth, and an acceptable level of compost maturity. 31 refs., 4 figs., 5 tabs.« less

STABILIZATION OF MERCURY IN WASTE MATERIAL FROM THE SULFUR BANK MERCURY MINE, INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

Three innovative technologies for stabilization of mercury were demonstrated in a treatability study performed on two waste rock materials from the Sulfur Bank Mercury Mine, a Superfund site in northern California. The treatability study was jointly sponsored by two EPA programs:...

Anaerobic digestion of solid slaughterhouse waste: study of biological stabilization by Fourier Transform infrared spectroscopy and thermogravimetry combined with mass spectrometry.

PubMed

Cuetos, María José; Gómez, Xiomar; Otero, Marta; Morán, Antonio

2010-07-01

In this paper, Fourier Transform infrared spectroscopy (FTIR) along with thermogravimetric analysis together with mass spectrometry (TG-MS analysis) were employed to study the organic matter transformation attained under anaerobic digestion of slaughterhouse waste and to establish the stability of the digestates obtained when compared with fresh wastes. Digestate samples studied were obtained from successful digestion and failed systems treating slaughterhouse waste and the organic fraction of municipal solid wastes. The FTIR spectra and TG profiles from well stabilized products (from successful digestion systems) showed an increase in the aromaticity degree and the reduction of volatile content and aliphatic structures as stabilization proceeded. On the other hand, the FTIR spectra of non-stable reactors showed a high aliphaticity degree and fat content. When comparing differential thermogravimetry (DTG) profiles of the feed and digestate samples obtained from all successful anaerobic systems, a reduction in the intensity of the low-temperature range (approximately 300 degrees C) peak was observed, while the weight loss experienced at high-temperature (450-550 degrees C) was variable for the different systems. Compared to the original waste, the intensity of the weight loss peak in the high-temperature range decreased in the reactors with higher hydraulic retention time (HRT) whereas its intensity increased and the peak was displaced to higher temperatures for the digesters with lower HRT.

Microencapsulation and storage stability of polyphenols from Vitis vinifera grape wastes.

PubMed

Aizpurua-Olaizola, Oier; Navarro, Patricia; Vallejo, Asier; Olivares, Maitane; Etxebarria, Nestor; Usobiaga, Aresatz

2016-01-01

Wine production wastes are an interesting source of natural polyphenols. In this work, wine wastes extracts were encapsulated through vibration nozzle microencapsulation using sodium alginate as polymer and calcium chloride as hardening reagent. An experimental design approach was used to obtain calcium-alginate microbeads with high polyphenol content and good morphological features. In this way, the effect of pressure, frequency, voltage and the distance to the gelling bath were optimized for two nozzles of 150 and 300 μm. Long-term stability of the microbeads was studied for 6 months taking into account different storage conditions: temperatures (4 °C and room temperature), in darkness and in presence of light, and the addition of chitosan to the gelling bath. Encapsulated polyphenols were found to be much more stable compared to free polyphenols regardless the encapsulation procedure and storage conditions. Moreover, slightly lower degradation rates were obtained when chitosan was added to the gelling bath. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of concrete mix proportions for minimizing/eliminating shrinkage cracks in slabs and high performance grouts : final report.

DOT National Transportation Integrated Search

2017-02-01

The two focus areas of this research address longstanding problems of (1) cracking of concrete slabs due to creep and shrinkage and (2) high performance compositions for grouting and joining precast concrete structural elements. Cracking of bridge de...

Long-term leaching behavior of phenol in cement/activated-carbon solidified/stabilized hazardous waste.

PubMed

Liu, Jianguo; Nie, Xiaoqin; Zeng, Xianwei; Su, Zhaoji

2013-01-30

The long-term leaching behavior of phenol in solidified/stabilized (S/S) hazardous wastes cured for 28 d with different amounts of activated carbon (AC) was investigated using synthetic inorganic acid (H(2)SO(4):HNO(3) = 2:1, pH = 3.2), acetic acid buffer (HAc/NaAc, pH = 4.93), and deionized water as leachants to simulate the leaching of phenol in three exposure scenarios: acid-precipitation, co-disposal, and neutral-precipitation. Phenol immobilization was enhanced by AC adsorption and impaired by the growth of micropores with increasing amount of AC; thus the optimal added amount of AC to be to added S/S wastes was 2%. The leaching behavior of phenol in co-disposal scenario was unpredictable due to inadequate ionization of HAc in the HAc-NaAc buffer solution. The findings indicated that S/S products should be disposed of in hazardous waste landfills rather than municipal solid waste landfills. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison between rice husk ash grown in different regions for stabilizing fly ash from a solid waste incinerator.

PubMed

Benassi, L; Bosio, A; Dalipi, R; Borgese, L; Rodella, N; Pasquali, M; Depero, L E; Bergese, P; Bontempi, E

2015-08-15

The Stabilization of heavy metals from municipal solid waste incineration (MSWI) fly ash by rice husk ash (RHA) is under intense study as an effective strategy to recover and reuse industrial and agricultural waste together. We compare the metal entrapment performances of RHA from different Asian rice sources – namely from Japonica rice grown in Italy and Indica rice grown in India – Physicochemical and morphological characterization of the final stabilized material show that the same thermal treatment may result in marked structural differences in the silica contained in the two RHA. Remarkably, one of them displays a crystalline silica content, although obtained by a thermal treatment below 800 °C. We also find that the presence of an alkali metal ion (potassium) in the rice husk plays a crucial role in the attainment of the final silica phase. These physicochemical differences are mirrored by different stabilization yields by the two RHA. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rice Husk Ash to Stabilize Heavy Metals Contained in Municipal Solid Waste Incineration Fly Ash: First Results by Applying New Pre-treatment Technology

PubMed Central

Benassi, Laura; Franchi, Federica; Catina, Daniele; Cioffi, Flavio; Rodella, Nicola; Borgese, Laura; Pasquali, Michela; Depero, Laura E.; Bontempi, Elza

2015-01-01

A new technology was recently developed for municipal solid waste incineration (MSWI) fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA), an agricultural byproduct material (COSMOS-RICE project). The obtained final inert can be applied in several applications to produce “green composites”. In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC) was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste. PMID:28793605

Thermal Stability and Material Balance of Nanomaterials in Waste Incineration

NASA Astrophysics Data System (ADS)

Paur, H.-R.; Baumann, W.; Hauser, M.; Lang, I.; Teuscher, N.; Seifert, H.; Stapf, D.

2017-06-01

Nanostructured materials are widely used to improve the properties of consumer products such as tires, cosmetics, light weight equipment etc. Due to their complex composition these products are hardly recycled and thermal treatment is preferred. In this study we investigated the thermal stability and material balance of nanostructured metal oxides in flames and in an industrial waste incinerator. We studied the size distribution of nanostructured metal oxides (CeO2, TiO2, SiO2) in a flame reactor and in a heated reaction tube. In the premixed ethylene/air flame, nano-structured CeO2 partly evaporates forming a new particle mode. This is probably due to chemical reactions in the flame. In addition sintering of agglomerates takes place in the flame. In the electrically heated reaction tube however only sintering of the agglomerated nanomaterials is observed. Ceria has a low background in waste incinerators and is therefore a suitable tracer for investigating the fate of nanostructured materials. Low concentrations of Ceria were introduced by a two-phase nozzle into the post-combustion zone of a waste incinerator. By the incineration of coal dust in a burning chamber the Ceria nanoparticles are mainly found in the size range of the fly ash (1 - 10 µm) because of agglomeration. With gas as a fuel less agglomeration was observed and the Ceria nanoparticles were in the particle size range below 1 µm.

Cadmium tolerance and antibiotic resistance in Escherichia coli isolated from waste stabilization ponds.

PubMed

Patra, Sova; Das, T K; Avila, C; Cabello, V; Castillo, F; Sarkar, D; Lahiri, Susmita; Jana, B B

2012-04-01

The incidence pattern of cadmium tolerance and antibiotics resistance by Escherichia coli was examined periodically from the samples of water, sludge and intestine of fish raised in waste stabilization ponds in a sewage treatment plant. Samples of water and sludge were collected from all the selected ponds and were monitored for total counts of fecal coliform (FC), total coliform (TC) and the population of Escherichia coli, which was also obtained from the intestine of fishes. Total counts of both FC and TC as well as counts of E. coli were markedly reduced from the facultative pond to the last maturation pond. Tolerance limit to cadmium by E. coli tended to decline as the distance of the sewage effluent from the source increased; the effective lethal concentration of cadmium ranged from 0.1 mM in split chamber to 0.05 mM in first maturation pond. E. coli isolated from water, sludge and fish gut were sensitive to seven out of ten antibiotics tested. It appears that holistic functions mediated through the mutualistic growth of micro algae and heterotrophic bacteria in the waste stabilization ponds were responsible for the promotion of water quality and significant reduction of coliform along the sewage effluent gradient.

The Performance of Underground Radioactive Waste Storage Tanks at the Savannah River Site: A 60-Year Historical Perspective

DOE PAGES

Wiersma, Bruce J.

2014-02-08

The Savannah River Site produced weapons-grade materials for nearly 35 years between 1953 and 1988. The legacy of this production is nearly 37 million gallons of radioactive waste. Since the 1950s, the liquid waste has been stored in large, underground carbon steel waste tanks. During the past 20 years, the site has begun to process the waste so that it may be stored in vitrified and grout forms, which are more suitable for long-term storage. Over the history of the site, some tanks have experienced leakage of the waste to the secondary containment. This article is a review of themore » instances of leakage and corrosion degradation that the tanks and associated equipment have experienced since the first tanks were built. Furthermore, the activities that the site has taken to mitigate the degradation and manage the service life of the tank for its anticipated lifetime are reviewed.« less

Slope stability of bioreactor landfills during leachate injection: effects of heterogeneous and anisotropic municipal solid waste conditions.

PubMed

Giri, Rajiv K; Reddy, Krishna R

2014-03-01

In bioreactor landfills, leachate recirculation can significantly affect the stability of landfill slope due to generation and distribution of excessive pore fluid pressures near side slope. The current design and operation of leachate recirculation systems do not consider the effects of heterogeneous and anisotropic nature of municipal solid waste (MSW) and the increased pore gas pressures in landfilled waste caused due to leachate recirculation on the physical stability of landfill slope. In this study, a numerical two-phase flow model (landfill leachate and gas as immiscible phases) was used to investigate the effects of heterogeneous and anisotropic nature of MSW on moisture distribution and pore-water and capillary pressures and their resulting impacts on the stability of a simplified bioreactor landfill during leachate recirculation using horizontal trench system. The unsaturated hydraulic properties of MSW were considered based on the van Genuchten model. The strength reduction technique was used for slope stability analyses as it takes into account of the transient and spatially varying pore-water and gas pressures. It was concluded that heterogeneous and anisotropic MSW with varied unit weight and saturated hydraulic conductivity significantly influenced the moisture distribution and generation and distribution of pore fluid pressures in landfill and considerably reduced the stability of bioreactor landfill slope. It is recommended that heterogeneous and anisotropic MSW must be considered as it provides a more reliable approach for the design and leachate operations in bioreactor landfills.

Stable isotope signatures for characterising the biological stability of landfilled municipal solid waste

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

Wimmer, Bernhard, E-mail: bernhard.wimmer@ait.ac.at; Hrad, Marlies; Huber-Humer, Marion

Highlights: ► The isotopic signature of δ{sup 13}C-DIC of leachates is linked to the reactivity of MSW. ► Isotopic signatures of leachates depend on aerobic/anaerobic conditions in landfills. ► In situ aeration of landfills can be monitored by isotope analysis in leachate. ► The isotopic analysis of leachates can be used for assessing the stability of MSW. ► δ{sup 13}C-DIC of leachates helps to define the duration of landfill aftercare. - Abstract: Stable isotopic signatures of landfill leachates are influenced by processes within municipal solid waste (MSW) landfills mainly depending on the aerobic/anaerobic phase of the landfill. We investigated themore » isotopic signatures of δ{sup 13}C, δ{sup 2}H and δ{sup 18}O of different leachates from lab-scale experiments, lysimeter experiments and a landfill under in situ aeration. In the laboratory, columns filled with MSW of different age and reactivity were percolated under aerobic and anaerobic conditions. In landfill simulation reactors, waste of a 25 year old landfill was kept under aerobic and anaerobic conditions. The lysimeter facility was filled with mechanically shredded fresh waste. After starting of the methane production the waste in the lysimeter containments was aerated in situ. Leachate and gas composition were monitored continuously. In addition the seepage water of an old landfill was collected and analysed periodically before and during an in situ aeration. We found significant differences in the δ{sup 13}C-value of the dissolved inorganic carbon (δ{sup 13}C-DIC) of the leachate between aerobic and anaerobic waste material. During aerobic degradation, the signature of δ{sup 13}C-DIC was mainly dependent on the isotopic composition of the organic matter in the waste, resulting in a δ{sup 13}C-DIC of −20‰ to −25‰. The production of methane under anaerobic conditions caused an increase in δ{sup 13}C-DIC up to values of +10‰ and higher depending on the actual reactivity of

Influence of fiber treatment on dimensional stabilities of rattan waste composite boards

NASA Astrophysics Data System (ADS)

Zuraida, A.; Insyirah, Y.; Maisarah, T.; Zahurin, H.

2018-01-01

The main drawback of using natural fibers in composite boards is its hydrophilic properties which absorb a high volume of moisture. This results in low dimensional stability of the produced composite boards. Hence, the purpose of this study is to investigate the effects of fibers’ treatment processes of the rattan waste fibers on the dimensional stabilities of composite boards. The collected fibers underwent two types of retting processes, namely a water treatment and alkaline treatment retting processes; where the fibers were soaked in water and a 1% sodium hydroxide (NaOH) solution, respectively. The fibers were dried and mixed with poly(lactic) acid (PLA) pellets with ratio of 30% fibers: 70% matrix; before being fabricated into composite boards via a hot-pressing process and were labelled as RF/PLA, WRF/PLA, CRF/PLA for untreated rattan, rattan treated by water retting, rattan treated by chemical retting, respectively. The produced composite boards were cut and soaked in water for 24 hours for dimensional stability in terms of water absorption and thickness swelling tests. The results showed that WRF/PLA has the lowest water absorption (3.2%), and the CRF/PLA had the highest water absorption (23.2%). The thickness swelling showed a similar trend as water absorption. The presence of void contents and fibers damaged the insides of the boards, which contributed to low dimensional stabilities of the composite boards. It can be concluded that water retting facilitated in improving dimensional stability of the produced composite board.

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

Not Available

The purpose of this analysis is to provide information necessary for the Department of Energy (DOE) to evaluate the practical utility of the Nitrate to Ammonia and Ceramic or Glass (NAC/NAG/NAX) process, which is under development in the Oak Ridge National Laboratory. The NAC/NACx/NAX process can convert aqueous radioactive nitrate-laden waste to a glass, ceramic, or grout solid waste form. The tasks include, but are not limited to, the following: Identify current commercial technologies to meet hazardous and radiological waste disposal requirements. The technologies may be thermal or non-thermal but must be all inclusive (i.e., must convert a radionuclide-containing nitratemore » waste with a pH around 12 to a stable form that can be disposed at permitted facilities); evaluate and compare DOE-sponsored vitrification, grouting, and minimum additive waste stabilization projects for life-cycle costs; compare the technologies above with respect to material costs, capital equipment costs, operating costs, and operating efficiencies. For the NAC/NAG/NAX process, assume aluminum reactant is government furnished and ammonia gas may be marketed; compare the identified technologies with respect to frequency of use within DOE for environmental management applications with appropriate rationale for use; Assess the potential size of the DOE market for the NAC/NAG/NAX process; assess and off-gas issues; and compare with international technologies, including life-cycle estimates.« less

UNDERGROUNG PLACEMENT OF COAL PROCESSING WASTE AND COAL COMBUSTION BY-PRODUCTS BASED PASTE BACKFILL FOR ENHANCED MINING ECONOMICS

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

Y.P. Chugh; D. Biswas; D. Deb

2002-06-01

This project has successfully demonstrated that the extraction ratio in a room-and-pillar panel at an Illinois mine can be increased from the current value of approximately 56% to about 64%, with backfilling done from the surface upon completion of all mining activities. This was achieved without significant ground control problems due to the increased extraction ratio. The mined-out areas were backfilled from the surface with gob, coal combustion by-products (CCBs), and fine coal processing waste (FCPW)-based paste backfill containing 65%-70% solids to minimize short-term and long-term surface deformations risk. This concept has the potential to increase mine productivity, reduce miningmore » costs, manage large volumes of CCBs beneficially, and improve the miner's health, safety, and environment. Two injection holes were drilled over the demonstration panel to inject the paste backfill. Backfilling was started on August 11, 1999 through the first borehole. About 9,293 tons of paste backfill were injected through this borehole with a maximum flow distance of 300-ft underground. On September 27, 2000, backfilling operation was resumed through the second borehole with a mixture of F ash and FBC ash. A high-speed auger mixer (new technology) was used to mix solids with water. About 6,000 tons of paste backfill were injected underground through this hole. Underground backfilling using the ''Groutnet'' flow model was simulated. Studies indicate that grout flow over 300-foot distance is possible. Approximately 13,000 tons of grout may be pumped through a single hole. The effect of backfilling on the stability of the mine workings was analyzed using SIUPANEL.3D computer program and further verified using finite element analysis techniques. Stiffness of the backfill mix is most critical for enhancing the stability of mine workings. Mine openings do not have to be completely backfilled to enhance their stability. Backfill height of about 50% of the seam height is

Effect of the raw materials and mixing ratio of composted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa.

PubMed

Kaboré, Théodore Wind-Tinbnoma; Houot, Sabine; Hien, Edmond; Zombré, Prosper; Hien, Victor; Masse, Dominique

2010-02-01

The effect of raw materials and their proportions in initial mixtures on organic matter (OM) stabilization and nitrogen (N) availability during pit composting in Sub-Saharan Africa was assessed using biochemical fractionation and laboratory incubations to characterize composts sampled throughout the composting process. Stabilization of OM occurred more rapidly in mixtures with slaughter-house wastes, it was progressive in mixture with household refuses while tree leaves compost remained unstable. Carbon mineralization from compost samples was positively correlated to water soluble and hemicellulose-like organic fractions. Mixtures containing large proportions of household refuses reached the highest stability and total N but available N remained weak. Slaughter-house wastes in the initial mixtures made possible to reach good OM stabilization and the largest N availability. The nature of initial mixing influenced composting parameters, OM stabilization and N availability. It is suggested mixing household refuses and slaughter-house wastes with tree leaves to reach better amending and fertilizer qualities of composts.

Anaerobic digestion of municipal solid wastes containing variable proportions of waste types.

PubMed

Akunna, J C; Abdullahi, Y A; Stewart, N A

2007-01-01

In many parts of the world there are significant seasonal variations in the production of the main organic wastes, food and green wastes. These waste types display significant differences in their biodegradation rates. This study investigated the options for ensuring process stability during the start up and operation of thermophilic high-solids anaerobic digestion of feedstock composed of varying proportions of food and green wastes. The results show that high seed sludge to feedstock ratio (or low waste loading rate) is necessary for ensuring process pH stability without chemical addition. It was also found that the proportion of green wastes in the feedstock can be used to regulate process pH, particularly when operating at high waste loading rates (or low seed sludge to feedstock ratios). The need for chemical pH correction during start-up and digestion operation decreased with increase in green wastes content of the feedstock. Food wastes were found to be more readily biodegradable leading to higher solids reduction while green wastes brought about pH stability and higher digestate solid content. Combining both waste types in various proportions brought about feedstock with varying buffering capacity and digestion performance. Thus, careful selection of feedstock composition can minimise the need for chemical pH regulation as well as reducing the cost for digestate dewatering for final disposal.

Data Package for Secondary Waste Form Down-Selection—Cast Stone

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

Serne, R. Jeffrey; Westsik, Joseph H.

2011-09-05

Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations andmore » leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.« less

DEMONSTRATION OF LEACHXS/ORCHESTRA CAPABILITIES BY SIMULATING CONSTITUENT RELEASE FROM A CEMENTITIOUS WASTE FORM IN A REINFORCED CONCRETE VAULT

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

Langton, C.; Meeussen, J.; Sloot, H.

2010-03-31

The objective of the work described in this report is to demonstrate the capabilities of the current version of LeachXS{trademark}/ORCHESTRA for simulating chemical behavior and constituent release processes in a range of applications that are relevant to the CBP. This report illustrates the use of LeachXS{trademark}/ORCHESTRA for the following applications: (1) Comparing model and experimental results for leaching tests for a range of cementitious materials including cement mortars, grout, stabilized waste, and concrete. The leaching test data includes liquid-solid partitioning as a function of pH and release rates based on laboratory column, monolith, and field testing. (2) Modeling chemical speciationmore » of constituents in cementitious materials, including liquid-solid partitioning and release rates. (3) Evaluating uncertainty in model predictions based on uncertainty in underlying composition, thermodynamic, and transport characteristics. (4) Generating predominance diagrams to evaluate predicted chemical changes as a result of material aging using the example of exposure to atmospheric conditions. (5) Modeling coupled geochemical speciation and diffusion in a three layer system consisting of a layer of Saltstone, a concrete barrier, and a layer of soil in contact with air. The simulations show developing concentration fronts over a time period of 1000 years. (6) Modeling sulfate attack and cracking due to ettringite formation. A detailed example for this case is provided in a separate article by the authors (Sarkar et al. 2010). Finally, based on the computed results, the sensitive input parameters for this type of modeling are identified and discussed. The chemical speciation behavior of substances is calculated for a batch system and also in combination with transport and within a three layer system. This includes release from a barrier to the surrounding soil as a function of time. As input for the simulations, the physical and chemical properties of

Stability assessment of lycopene microemulsion prepared using tomato industrial waste against various processing conditions.

PubMed

Amiri-Rigi, Atefeh; Abbasi, Soleiman

2017-11-01

Green separation techniques are growing at a greater rate than solvent extraction as a result of the constant consumer drive to 'go natural'. Considering the increasing evidence of the health benefits of lycopene and massive tomato industrial waste, in the present study, lycopene was extracted from tomato industrial waste using microemulsion technique and its mean droplet size and size distribution was determined. Moreover, the effects of pasteurization, sterilization, freeze-thaw cycles and ultraviolet (UV) irradiation on the thermodynamic stability, turbidity and lycopene concentration of the lycopene microemulsion were monitored. Freeze-thaw cycles, pasteurization and short exposure to UV irradiation showed no or negligible influence on lycopene content and turbidity of the microemulsion. However, long exposure to UV (260 min) reduced the lycopene content and turbidity by 34% and 10%, respectively. HHST (higher-heat shorter-time) and sterilization also reduced lycopene content (25%) and increased turbidity (32%). The lycopene microemulsion showed satisfactory stability over a process where its monodispersity and nanosize could be of potential advantage to the food and related industries. Regarding the carcinogenicity of synthetic colourants, potential applications of the lycopene microemulsion include in soft drinks and minced meat, which would result in a better colour and well-documented health-promoting qualities. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Anaerobic co-digestion of livestock and vegetable processing wastes: fibre degradation and digestate stability.

PubMed

Molinuevo-Salces, Beatriz; Gómez, Xiomar; Morán, Antonio; García-González, Mari Cruz

2013-06-01

Anaerobic digestion of livestock wastes (swine manure (SM) and poultry litter (PL)) and vegetable processing wastes (VPW) mixtures was evaluated in terms of methane yield, volatile solids removal and lignocellulosic material degradation. Batch experiments were performed with 2% VS (volatile solids) to ensure complete conversion of TVFAs (total volatile fatty acids) and to avoid ammonia inhibition. Experimental methane yields obtained for the mixtures resulted in higher values than those obtained from the sum of the methane yields from the individual components. VPW addition to livestock wastes before anaerobic digestion also resulted in improved VS elimination. In SM-VPW co-digestions, CH4 yield increased from 111 to 244 mL CH4 g VS added(-1), and the percentage of VS removed increased from 50% to 86%. For PL-VPW co-digestions, the corresponding values were increased from 158 to 223 mL CH4 g VS added(-1) and from 70% to 92% VS removed. Hemicelluloses and more than 50% of cellulose were degraded during anaerobic digestion. Thermal analyses indicated that the stabilization of the wastes during anaerobic digestion resulted in significantly less energy being released by digestate samples than fresh samples. Copyright © 2013 Elsevier Ltd. All rights reserved.

ENVIRONMENTAL TECHNOLOGY VERIFICATION PROGRAM: PROTOCOL FOR THE VERIFICATION OF GROUTING MATERIALS FOR INFRASTRUCTURE REHABILITATION AT THE UNIVERSITY OF HOUSTON - CIGMAT

EPA Science Inventory

This protocol was developed under the Environmental Protection Agency's Environmental Technology Verification (ETV) Program, and is intended to be used as a guide in preparing laboratory test plans for the purpose of verifying the performance of grouting materials used for infra...

Residence time effects on technetium reduction in slag-based cementitious materials.

PubMed

Arai, Yuji; Powell, Brian A; Kaplan, D I

2018-01-15

A long-term disposal of technetium-99 ( 99 Tc) has been considered in a type of cementitious formulation, slag-based grout, at the U.S. Department of Energy, Savannah River Site, Aiken SC, U.S.A. Blast furnace slag, which contains S and Fe electron donors, has been used in a mixture with fly ash, and Portland cement to immobilize 99 Tc(VII)O 4 - (aq) in low level radioactive waste via reductive precipitation reaction. However the long-term stability of Tc(IV) species is not clearly understood as oxygen gradually diffuses into the solid structure. In this study, aging effects of Tc speciation were investigated as a function of depth (<2.5cm) in slag-based grout using X-ray absorption spectroscopy. All of Fe(II) in solids was oxidized to Fe(III) after 117d. However, elemental S, sulfide, and sulfoxide persists at the 0-8mm depths even after 485d, suggesting the presence of a reduced zone below the surface few millimeters. Pertechnetate was successfully reduced to Tc(IV) after 29d. Distorted hydrolyzed Tc(IV) octahedral molecules were partially sulfidized and or polymerized at all depths (0-8mm) and were stable in 485d aged sample. The results of this study suggest that variable S species contribute to stabilize the partially sulfidized Tc(IV) species in aged slag-based grout. Copyright © 2017 Elsevier B.V. All rights reserved.

Use of thermal analysis techniques (TG-DSC) for the characterization of diverse organic municipal waste streams to predict biological stability prior to land application

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

Fernandez, Jose M., E-mail: joseman@sas.upenn.edu; Plaza, Cesar; Polo, Alfredo

2012-01-15

Highlights: Black-Right-Pointing-Pointer Thermal analysis was used to assess stability and composition of organic matter in three diverse municipal waste streams. Black-Right-Pointing-Pointer Results were compared with C mineralization during 90-day incubation, FTIR and {sup 13}C NMR. Black-Right-Pointing-Pointer Thermal analysis reflected the differences between the organic wastes before and after the incubation. Black-Right-Pointing-Pointer The calculated energy density showed a strong correlation with cumulative respiration. Black-Right-Pointing-Pointer Conventional and thermal methods provide complimentary means of characterizing organic wastes. - Abstract: The use of organic municipal wastes as soil amendments is an increasing practice that can divert significant amounts of waste from landfill, and providesmore » a potential source of nutrients and organic matter to ameliorate degraded soils. Due to the high heterogeneity of organic municipal waste streams, it is difficult to rapidly and cost-effectively establish their suitability as soil amendments using a single method. Thermal analysis has been proposed as an evolving technique to assess the stability and composition of the organic matter present in these wastes. In this study, three different organic municipal waste streams (i.e., a municipal waste compost (MC), a composted sewage sludge (CS) and a thermally dried sewage sludge (TS)) were characterized using conventional and thermal methods. The conventional methods used to test organic matter stability included laboratory incubation with measurement of respired C, and spectroscopic methods to characterize chemical composition. Carbon mineralization was measured during a 90-day incubation, and samples before and after incubation were analyzed by chemical (elemental analysis) and spectroscopic (infrared and nuclear magnetic resonance) methods. Results were compared with those obtained by thermogravimetry (TG) and differential scanning calorimetry (DSC

Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

NASA Astrophysics Data System (ADS)

Zhao, Tong; Liu, Changyou

2017-12-01

Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

A hybrid method for quasi-three-dimensional slope stability analysis in a municipal solid waste landfill.

PubMed

Yu, L; Batlle, F

2011-12-01

Limited space for accommodating the ever increasing mounds of municipal solid waste (MSW) demands the capacity of MSW landfill be maximized by building landfills to greater heights with steeper slopes. This situation has raised concerns regarding the stability of high MSW landfills. A hybrid method for quasi-three-dimensional slope stability analysis based on the finite element stress analysis was applied in a case study at a MSW landfill in north-east Spain. Potential slides can be assumed to be located within the waste mass due to the lack of weak foundation soils and geosynthetic membranes at the landfill base. The only triggering factor of deep-seated slope failure is the higher leachate level and the relatively high and steep slope in the front. The valley-shaped geometry and layered construction procedure at the site make three-dimensional slope stability analyses necessary for this landfill. In the finite element stress analysis, variations of leachate level during construction and continuous settlement of the landfill were taken into account. The "equivalent" three-dimensional factor of safety (FoS) was computed from the individual result of the two-dimensional analysis for a series of evenly spaced cross sections within the potential sliding body. Results indicate that the hybrid method for quasi-three-dimensional slope stability analysis adopted in this paper is capable of locating roughly the spatial position of the potential sliding mass. This easy to manipulate method can serve as an engineering tool in the preliminary estimate of the FoS as well as the approximate position and extent of the potential sliding mass. The result that FoS obtained from three-dimensional analysis increases as much as 50% compared to that from two-dimensional analysis implies the significance of the three-dimensional effect for this study-case. Influences of shear parameters, time elapse after landfill closure, leachate level as well as unit weight of waste on FoS were also

Prediction of chemical speciation in stabilized/solidified wastes using a general chemical equilibrium model. Part 1: Chemical representation of cementitious binders

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

Park, J.Y.; Batchelor, B.

1999-03-01

Chemical equilibrium models are useful to evaluate stabilized/solidified waste. A general equilibrium model, SOLTEQ, a modified version of MINTEQA2 for S/S, was applied to predict the chemical speciations in the stabilized/solidified waste form. A method was developed to prepare SOLTEQ input data that can chemically represent various stabilized/solidified binders. Taylor`s empirical model was used to describe partitioning of alkali ions. As a result, SOLTEQ could represent chemical speciation in pure binder systems such as ordinary Portland cement and ordinary Portland cement + fly ash. Moreover, SOLTEQ could reasonably describe the effects on the chemical speciation due to variations in water-to-cement,more » fly ash contents, and hydration times of various binder systems. However, this application of SOLTEQ was not accurate in predicting concentrations of Ca, Si, and SO{sub 4} ions, due to uncertainties in the CSH solubility model and K{sub sp} values of cement hydrates at high pH values.« less

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

Carter, E.

A new class of grout material based on molten wax offers a dramatic improvement in permeation grouting performance. This new material makes a perfect in situ containment of buried radioactive waste both feasible and cost effective. This paper describes various ways the material can be used to isolate buried waste in situ. Potential applications described in the paper include buried radioactive waste in deep trenches, deep shafts, Infiltration trenches, and large buried objects. Use of molten wax for retrieval of waste is also discussed. Wax can also be used for retrieval of air sensitive materials or drummed waste. This papermore » provides an analysis of the methods of application and the expected performance and cost of several potential projects. (authors)« less

Mercury stabilization in chemically bonded phosphate ceramics

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

Wagh, A. S.; Singh, D.; Jeong, S. Y.

2000-04-04

Mercury stabilization and solidification is a significant challenge for conventional stabilization technologies. This is because of the stringent regulatory limits on leaching of its stabilized products. In a conventional cement stabilization process, Hg is converted at high pH to its hydroxide, which is not a very insoluble compound; hence the preferred route for Hg sulfidation to convert it into insoluble cinnabar (HgS). Unfortunately, efficient formation of this compound is pH-dependent. At a high pH, one obtains a more soluble Hg sulfate, in a very low pH range, insufficient immobilization occurs because of the escape of hydrogen sulfide, while efficient formationmore » of HgS occurs only in a moderately acidic region. Thus, the pH range of 4 to 8 is where stabilization with Chemically Bonded Phosphate Ceramics (CBPC) is carried out. This paper discusses the authors experience on bench-scale stabilization of various US Department of Energy (DOE) waste streams containing Hg in the CBPC process. This process was developed to treat DOE's mixed waste streams. It is a room-temperature-setting process based on an acid-base reaction between magnesium oxide and monopotassium phosphate solution that forms a dense ceramic within hours. For Hg stabilization, addition of a small amount (< 1 wt.%) of Na{sub 2}S or K{sub 2}S is sufficient in the binder composition. Here the Toxicity Characteristic Leaching Procedure (TCLP) results on CBPC waste forms of surrogate waste streams representing secondary Hg containing wastes such as combustion residues and Delphi DETOX{trademark} residues are presented. The results show that although the current limit on leaching of Hg is 0.2 mg/L, the results from the CBPC waste forms are at least one order lower than this stringent limit. Encouraged by these results on surrogate wastes, they treated actual low-level Hg-containing mixed waste from their facility at Idaho. TCLP results on this waste are presented here. The efficient

Bio-lubricants derived from waste cooking oil with improved oxidation stability and low-temperature properties.

PubMed

Li, Weimin; Wang, Xiaobo

2015-01-01

Waste cooking oil (WCO) was chemically modified via epoxidation using H2O2 followed by transesterification with methanol and branched alcohols (isooctanol, isotridecanol and isooctadecanol) to produce bio-lubricants with improved oxidative stability and low temperature properties. Physicochemical properties of synthesized bio-lubricants such as pour point (PP), cloud point (CP), viscosity, viscosity index (VI), oxidative stability, and corrosion resistant property were determined according to standard methods. The synthesized bio-lubricants showed improved low temperature flow performances compared with WCO, which can be attributing to the introduction of branched chains in their molecular structures. What's more, the oxidation stability of the WCO showed more than 10 folds improvement due to the elimination of -C=C-bonds in the WCO molecule. Tribological performances of these bio-lubricants were also investigated using four-ball friction and wear tester. Experimental results showed that derivatives of WCO exhibited favorable physicochemical properties and tribological performances which making them good candidates in formulating eco-friendly lubricants.

Stabilizing Waste Materials for Landfills

ERIC Educational Resources Information Center

Environmental Science and Technology, 1977

1977-01-01

The test procedures used to evaluate the suitability of landfilled materials of varying stability and to determine the leachate from such materials are reviewed. A process for stabilizing a mixture of sulfur dioxide sludge, fly ash, and bottom ash with lime and other additives for deposition in landfills is detailed. (BT)

Stable isotope signatures for characterising the biological stability of landfilled municipal solid waste.

PubMed

Wimmer, Bernhard; Hrad, Marlies; Huber-Humer, Marion; Watzinger, Andrea; Wyhlidal, Stefan; Reichenauer, Thomas G

2013-10-01

stability of the organic matter in landfilled municipal solid waste and can be used for monitoring the progress of in situ aeration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Performance Test on Polymer Waste Form - 12137

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

Lee, Se Yup

Polymer solidification was attempted to produce stable waste form for the boric acid concentrates and the dewatered spent resins. The polymer mixture was directly injected into the mold or drum which was packed with the boric acid concentrates and the dewatered spent resins, respectively. The waste form was produced by entirely curing the polymer mixture. A series of performance tests was conducted including compressive strength test, water immersion test, leach test, thermal stability test, irradiation stability test and biodegradation stability test for the polymer waste forms. From the results of the performance tests for the polymer waste forms, it ismore » believed that the polymer waste form is very stable and can satisfy the acceptance criteria for permanent disposal. At present, performance tests with full scale polymer waste forms are being carried out in order to obtain qualification certificate by the regulatory institute in Korea. Polymer waste forms were prepared with the surrogate of boric acid concentrates and the surrogate of spent ion exchange resins respectively. Waste forms were also made in lab scale and in full scale. Lab. scale waste forms were directly subjected to a series of the performance tests. In the case of full scale waste form, the test specimens for the performance test were taken from a part of waste form by coring. A series of performance tests was conducted including compressive strength test, thermal stability test, irradiation stability test and biodegradation stability test, water immersion test, leach test, and free standing water for the polymer waste forms. In addition, a fire resistance test was performed on the waste forms by the requirement of the regulatory institute in Korea. Every polymer waste forms containing the boric acid concentrates and the spent ion exchange resins had exhibited excellent structural integrity of more than 27.58 MPa (4,000 psi) of compressive strength. On thermal stability testing

Validation of an in situ solidification/stabilization technique for hazardous barium and cyanide waste for safe disposal into a secured landfill.

PubMed

Vaidya, Rucha; Kodam, Kisan; Ghole, Vikram; Surya Mohan Rao, K

2010-09-01

The aim of the present study was to devise and validate an appropriate treatment process for disposal of hazardous barium and cyanide waste into a landfill at a Common Hazardous Waste Treatment Storage Disposal Facility (CHWTSDF). The waste was generated during the process of hardening of steel components and contains cyanide (reactive) and barium (toxic) as major contaminants. In the present study chemical fixation of the contaminants was carried out. The cyanide was treated by alkali chlorination with calcium hypochlorite and barium by precipitation with sodium sulfate as barium sulfate. The pretreated mixture was then solidified and stabilized by binding with a combination of slag cement, ordinary Portland cement and fly ash, molded into blocks (5 x 5 x 5 cm) and cured for a period of 3, 7 and 28 days. The final experiments were conducted with 18 recipe mixtures of waste + additive:binder (W:B) ratios. The W:B ratios were taken as 80:20, 70:30 and 50:50. The optimum proportions of additives and binders were finalized on the basis of the criteria of unconfined compressive strength and leachability. The leachability studies were conducted using the Toxicity Characteristic Leaching Procedure. The blocks were analyzed for various physical and leachable chemical parameters at the end of each curing period. Based on the results of the analysis, two recipe mixtures, with compositions - 50% of [waste + (120 g Ca(OCl)(2) + 290 g Na(2)SO(4)) kg(-1) of waste] + 50% of binders, were validated for in situ stabilization into a secured landfill of CHWTSDF. 2010 Elsevier Ltd. All rights reserved.

Treatment of mercury containing waste

DOEpatents

Kalb, Paul D.; Melamed, Dan; Patel, Bhavesh R; Fuhrmann, Mark

2002-01-01

A process is provided for the treatment of mercury containing waste in a single reaction vessel which includes a) stabilizing the waste with sulfur polymer cement under an inert atmosphere to form a resulting mixture and b) encapsulating the resulting mixture by heating the mixture to form a molten product and casting the molten product as a monolithic final waste form. Additional sulfur polymer cement can be added in the encapsulation step if needed, and a stabilizing additive can be added in the process to improve the leaching properties of the waste form.

River Protection Project (RPP) Dangerous Waste Training Plan

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

POHTO, R.E.

2000-03-09

This supporting document contains the training plan for dangerous waste management at River Protection Project TSD Units. This document outlines the dangerous waste training program developed and implemented for all Treatment, Storage, and Disposal (TSD) Units operated by River Protection Project (RPP) in the Hanford 200 East, 200 West and 600 Areas and the <90 Day Accumulation Area at 209E. Operating TSD Units managed by RPP are: the Double-Shell Tank (DST) System, 204-AR Waste Unloading Facility, Grout, and the Single-Shell Tank (SST) System. The program is designed in compliance with the requirements of Washington Administrative Code (WAC) 173-303-330 and Titlemore » 40 Code of Federal Regulations (CFR) 265.16 for the development of a written dangerous waste training program and the Hanford Facility Permit. Training requirements were determined by an assessment of employee duties and responsibilities. The RPP training program is designed to prepare employees to operate and maintain the Tank Farms in a safe, effective, efficient, and environmentally sound manner. In addition to preparing employees to operate and maintain the Tank Farms under normal conditions, the training program ensures that employees are prepared to respond in a prompt and effective manner should abnormal or emergency conditions occur. Emergency response training is consistent with emergency responses outlined in the following Building Emergency Plans: HNF-IP-0263-TF and HNF-=IP-0263-209E.« less

Municipal waste stabilization in a reactor with an integrated active and passive aeration system.

PubMed

Kasinski, Slawomir; Slota, Monika; Markowski, Michal; Kaminska, Anna

2016-04-01

To test whether an integrated passive and active aeration system could be an effective solution for aerobic decomposition of municipal waste in technical conditions, a full-scale composting reactor was designed. The waste was actively aerated for 5d, passively aerated for 35 d, and then actively aerated for 5d, and the entire composting process was monitored. During the 45-day observation period, changes in the fractional, morphological and physico-chemical characteristics of the waste at the top of the reactor differed from those in the center of the reactor. The fractional and morphological analysis made during the entire process of stabilization, showed the total reduction of organic matter measured of 82 wt% and 86 wt% at the respective depths. The reduction of organic matter calculated using the results of Lost of Ignition (LOI) and Total Organic Carbon (TOC) showed, respectively, 40.51-46.62% organic matter loss at the top and 45.33-53.39% in the center of the reactor. At the end of the process, moisture content, LOI and TOC at the top were 3.29%, 6.10% and 4.13% higher, respectively, than in the center. The results showed that application of passive aeration in larger scale simultaneously allows the thermophilic levels to be maintained during municipal solid waste composting process while not inhibiting microbial activity in the reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of remedial grouting on the ground-water flow system at Red Rock Dam near Pella, Iowa

USGS Publications Warehouse

Linhart, S. Mike; Schaap, Bryan D.

2001-01-01

Hydrographs, statistical analysis of waterlevel data, and water-chemistry data suggest that underseepage on the northeast side of the dam has been reduced but not completely eliminated. Some areas appear to have been affected to a greater degree and for a longer period of time than other areas. Future monitoring of water levels, water chemistry, and stable isotopes can aid in the evaluation of the long-term effectiveness of remedial grouting.

DSC and curing kinetics study of epoxy grouting diluted with furfural -acetone slurry

NASA Astrophysics Data System (ADS)

Yin, H.; Sun, D. W.; Li, B.; Liu, Y. T.; Ran, Q. P.; Liu, J. P.

2016-07-01

The use of furfural-acetone slurry as active diluents of Bisphenol-A epoxy resin (DGEBA) groutings has been studied by dynamic and non-isothermal DSC for the first time. Curing kinetics study was investigated by non-isothermal differential scanning calorimetries at different heating rates. Activation enery (Ea) was calculated based on Kissinger and Ozawa Methods, and the results showed that Ea increased from 58.87 to 71.13KJ/mol after the diluents were added. The furfural-acetone epoxy matrix could cure completely at the theoretical curing temperature of 365.8K and the curing time of 139mins, which were determined by the kinetic model parameters.

Use of thermal analysis techniques (TG-DSC) for the characterization of diverse organic municipal waste streams to predict biological stability prior to land application.

PubMed

Fernández, José M; Plaza, César; Polo, Alfredo; Plante, Alain F

2012-01-01

The use of organic municipal wastes as soil amendments is an increasing practice that can divert significant amounts of waste from landfill, and provides a potential source of nutrients and organic matter to ameliorate degraded soils. Due to the high heterogeneity of organic municipal waste streams, it is difficult to rapidly and cost-effectively establish their suitability as soil amendments using a single method. Thermal analysis has been proposed as an evolving technique to assess the stability and composition of the organic matter present in these wastes. In this study, three different organic municipal waste streams (i.e., a municipal waste compost (MC), a composted sewage sludge (CS) and a thermally dried sewage sludge (TS)) were characterized using conventional and thermal methods. The conventional methods used to test organic matter stability included laboratory incubation with measurement of respired C, and spectroscopic methods to characterize chemical composition. Carbon mineralization was measured during a 90-day incubation, and samples before and after incubation were analyzed by chemical (elemental analysis) and spectroscopic (infrared and nuclear magnetic resonance) methods. Results were compared with those obtained by thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques. Total amounts of CO(2) respired indicated that the organic matter in the TS was the least stable, while that in the CS was the most stable. This was confirmed by changes detected with the spectroscopic methods in the composition of the organic wastes due to C mineralization. Differences were especially pronounced for TS, which showed a remarkable loss of aliphatic and proteinaceous compounds during the incubation process. TG, and especially DSC analysis, clearly reflected these differences between the three organic wastes before and after the incubation. Furthermore, the calculated energy density, which represents the energy available per unit of organic

The influences of inoculants from municipal sludge and solid waste on compost stability, maturity and enzyme activities during chicken manure composting.

PubMed

Li, Shuyan; Li, Jijin; Yuan, Jing; Li, Guoxue; Zang, Bing; Li, Yangyang

2017-07-01

The aim of this study was to investigate the influence of inoculants on compost stability, maturity and enzyme activities during composting of chicken manure and cornstalk. Two microbial inoculants (originated from aerobic municipal sludge and municipal solid waste, respectively) were used in composting at the rate of 0.3% of initial raw materials (wet weight). No microbial inoculums were added to the control. The experiment was conducted under aerobic conditions for 53 days. The results show that enzyme activity is an important index to comprehensively evaluate the composting stability and maturity. Microbes originated from sludge works best in terms of composting stability and maturity (C:N ratio decreased from 15.5 to 10, and germination index increased to 109%). Microbial inoculums originated from sludge and municipal solid waste extended the time of thermophilic phase for 11 and 7 days, respectively. Microbial inoculums originated from sludge and MSW significantly increased the average of catalase activity (by 15.0% and 12.1%, respectively), urease activity (by 21.5% and 12.2%, respectively) and cellulase activity (by 32.1% and 26.1%, respectively) during composting.

Impact assessment of intermediate soil cover on landfill stabilization by characterizing landfilled municipal solid waste.

PubMed

Qi, Guangxia; Yue, Dongbei; Liu, Jianguo; Li, Rui; Shi, Xiaochong; He, Liang; Guo, Jingting; Miao, Haomei; Nie, Yongfeng

2013-10-15

Waste samples at different depths of a covered municipal solid waste (MSW) landfill in Beijing, China, were excavated and characterized to investigate the impact of intermediate soil cover on waste stabilization. A comparatively high amount of unstable organic matter with 83.3 g kg(-1) dry weight (dw) total organic carbon was detected in the 6-year-old MSW, where toxic inorganic elements containing As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn of 10.1, 0.98, 85.49, 259.7, 530.4, 30.5, 84.0, and 981.7 mg kg(-1) dw, respectively, largely accumulated because of the barrier effect of intermediate soil cover. This accumulation resulted in decreased microbial activities. The intermediate soil cover also caused significant reduction in moisture in MSW under the soil layer, which was as low as 25.9%, and led to inefficient biodegradation of 8- and 10-year-old MSW. Therefore, intermediate soil cover with low permeability seems to act as a barrier that divides a landfill into two landfill cells with different degradation processes by restraining water flow and hazardous matter. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Avocado waste for finishing pigs: Impact on muscle composition and oxidative stability during chilled storage.

PubMed

Hernández-López, Silvia H; Rodríguez-Carpena, Javier G; Lemus-Flores, Clemente; Grageola-Nuñez, Fernando; Estévez, Mario

2016-06-01

The utilization of agricultural waste materials for pig feeding may be an interesting option for reducing production costs and contributing to sustainability and environmental welfare. In the present study, a mixed diet enriched with avocado waste (TREATED) is used for finishing industrial genotype pigs. The muscle longissimus thoracis et lomborum (LTL) from TREATED pigs was analyzed for composition and oxidative and color stability and compared with muscles obtained from pigs fed a CONTROL diet. Dietary avocado had significant impact on the content and composition of intramuscular fat (IMF), reducing the lipid content in LTL muscles and increasing the degree of unsaturation. This did not increase the oxidative instability of samples. On the contrary, muscles from TREATED pigs had significantly lower lipid and protein oxidation rates during chilled storage. The color of the muscles from TREATED pigs was also preserved from oxidation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Possible interactions between recirculated landfill leachate and the stabilized organic fraction of municipal solid waste.

PubMed

Calabrò, Paolo S; Mancini, Giuseppe

2012-05-01

The stabilized organic fraction of municipal solid waste (SOFMSW) is a product of the mechanical/biological treatment (MBT) of mixed municipal solid waste (MMSW). SOFMSW is considered a 'grey' compost and the presence of pollutants (particularly heavy metals) and residual glass and plastic normally prevents agricultural use, making landfills the typical final destination for SOFMSW. Recirculation of leachate in landfills can be a cost-effective management option, but the long-term sustainability of such a practice must be verified. Column tests were carried out to examine the effect of SOFMSW on leachate recirculation. The results indicate that organic matter may be biologically degraded and metals (copper and zinc) are effectively entrapped through a combination of physical (adsorption), biological (bacterial sulfate reduction), and chemical (precipitation of metal sulfides) processes, while other chemicals (i.e. ammonia nitrogen and chloride) are essentially unaffected by filtration through SOFMSW.

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)

Impact of sludge layer geometry on the hydraulic performance of a waste stabilization pond.

PubMed

Ouedraogo, Faissal R; Zhang, Jie; Cornejo, Pablo K; Zhang, Qiong; Mihelcic, James R; Tejada-Martinez, Andres E

2016-08-01

Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems. Published by Elsevier Ltd.

Discontinuum-Equivalent Continuum Analysis of the Stability of Tunnels in a Deep Coal Mine Using the Distinct Element Method

NASA Astrophysics Data System (ADS)

Shreedharan, Srisharan; Kulatilake, Pinnaduwa H. S. W.

2016-05-01

An imperative task for successful underground mining is to ensure the stability of underground structures. This is more so for deep excavations which may be under significantly high stresses. In this manuscript, we present stability studies on two tunnels, a horseshoe-shaped and an inverted arch-shaped tunnel, in a deep coal mine in China, performed using the 3DEC distinct element code. The rock mass mechanical property values for the tunnel shapes have been estimated through a back-analysis procedure using available field deformation data. The back-analysis has been carried out through a pseudo-time dependent support installation routine which incorporates the effect of time through a stress-relaxation mechanism. The back-analysis indicates that the rock mass cohesion, tensile strength, uniaxial compressive strength, and elastic modulus values are about 35-45 % of the corresponding intact rock property values. Additionally, the importance of incorporating stress relaxation before support installation has been illustrated through the increased support factor of safety and reduced grout failures. The calibrated models have been analyzed for different supported and unsupported cases to estimate the significance and adequacy of the current supports being used in the mine and to suggest a possible optimization. The effects of supports have been demonstrated using deformations and yield zones around the tunnels, and average factors of safety and grout failures of the supports. The use of longer supports and floor bolting has provided greater stability for the rock masses around the tunnels. Finally, a comparison between the two differently shaped tunnels establishes that the inverted arch tunnel may be more efficient in reducing roof sag and floor heave for the existing geo-mining conditions.

Grout Impregnation of Pre-Placed Recycled Concrete Pavement (RCP) for Rapid Repair of Deteriorated Portland Cement Concrete Airfield Pavement

DTIC Science & Technology

2007-04-01

generation, to reduce the amount of cement required, and to provide additional tensile strength to the concrete. Although there was limited success with...generally less workable and requires more cement due to the increased water requirements. He further states that with the equipment currently...52- Table 9. Results of the Type III Grout Scoping Study Mixture Water Cement Ratio Sand Replicate Compressive Strength MPa (psi) Flow Cone

Fault Frictional Stability in a Nuclear Waste Repository

NASA Astrophysics Data System (ADS)

Orellana, Felipe; Violay, Marie; Scuderi, Marco; Collettini, Cristiano

2016-04-01

Exploitation of underground resources induces hydro-mechanical and chemical perturbations in the rock mass. In response to such disturbances, seismic events might occur, affecting the safety of the whole engineering system. The Mont Terri Rock Laboratory is an underground infrastructure devoted to the study of geological disposal of nuclear waste in Switzerland. At the site, it is intersected by large fault zones of about 0.8 - 3 m in thickness and the host rock formation is a shale rock named Opalinus Clay (OPA). The mineralogy of OPA includes a high content of phyllosilicates (50%), quartz (25%), calcite (15%), and smaller proportions of siderite and pyrite. OPA is a stiff, low permeable rock (2×10-18 m2), and its mechanical behaviour is strongly affected by the anisotropy induced by bedding planes. The evaluation of fault stability and associated fault slip behaviour (i.e. seismic vs. aseismic) is a major issue in order to ensure the long-term safety and operation of the repository. Consequently, experiments devoted to understand the frictional behaviour of OPA have been performed in the biaxial apparatus "BRAVA", recently developed at INGV. Simulated fault gouge obtained from intact OPA samples, were deformed at different normal stresses (from 4 to 30 MPa), under dry and fluid-saturated conditions. To estimate the frictional stability, the velocity-dependence of friction was evaluated during velocity steps tests (1-300 μm/s). Slide-hold-slide tests were performed (1-3000 s) to measure the amount of frictional healing. The collected data were subsequently modelled with the Ruina's slip dependent formulation of the rate and state friction constitutive equations. To understand the deformation mechanism, the microstructures of the sheared gouge were analysed. At 7 MPa normal stress and under dry conditions, the friction coefficient decreased from a peak value of μpeak,dry = 0.57 to μss,dry = 0.50. Under fluid-saturated conditions and same normal stress, the

Design and characterization of microporous zeolitic hydroceramic waste forms for the solidification and stabilization of sodium bearing wastes

NASA Astrophysics Data System (ADS)

Bao, Yun

During the production of nuclear weapon by the DOE, large amounts of liquid waste were generated and stored in millions of gallons of tanks at Savannah River, Hanford and INEEL sites. Typically, the waste contains large amounts of soluble NaOH, NaNO2 and NaNO3 and small amounts of soluble fission products, cladding materials and cleaning solution. Due to its high sodium content it has been called sodium bearing waste (SBW). We have formulated, tested and evaluated a new type of hydroceramic waste form specifically designed to solidify SBW. Hydroceramics can be made from an alumosilicate source such as metakaolin and NaOH solutions or the SBW itself. Under mild hydrothermal conditions, the mixture is transformed into a solid consisting of zeolites. This process leads to the incorporation of radionuclides into lattice sites and the cage structures of the zeolites. Hydroceramics have high strength and inherent stability in realistic geologic settings. The process of making hydroceramics from a series of SBWs was optimized. The results are reported in this thesis. Some SBWs containing relatively small amounts of NaNO3 and NaNO2 (SigmaNOx/Sigma Na<25 mol%) can be directly solidified with metakaolin. The remaining SBW having high concentrations of nitrate and nitrite (SigmaNOx/Sigma Na>25 mol%) require pretreatment since a zeolitic matrix such as cancrinite is unable to host more than 25 mol% nitrate/nitrite. Two procedures to denitrate/denitrite followed by solidification were developed. One is based on calcination in which a reducing agent such as sucrose and metakaolin have been chosen as a way of reducing nitrate and nitrite to an acceptable level. The resulting calcine can be solidified using additional metakaolin and NaOH to form a hydroceramic. As an alternate, a chemical denitration/denitrition process using Si and Al powders as the reducing agents, followed by adding metakaolin to the solution prepare a hydroceramic was also investigated. Si and Al not only are

Evaluation of methane oxidation activity in waste biocover soil during landfill stabilization.

PubMed

He, Ruo; Wang, Jing; Xia, Fang-Fang; Mao, Li-Juan; Shen, Dong-Sheng

2012-10-01

Biocover soil has been demonstrated to have high CH(4) oxidation capacity and is considered as a good alternative cover material to mitigate CH(4) emission from landfills, yet the response of CH(4) oxidation activity of biocover soils to the variation of CH(4) loading during landfill stabilization is poorly understood. Compared with a landfill cover soil (LCS) collected from Hangzhou Tianziling landfill cell, the development of CH(4) oxidation activity of waste biocover soil (WBS) was investigated using simulated landfill systems in this study. Although a fluctuation of influent CH(4) flux occurred during landfill stabilization, the WBS covers showed a high CH(4) removal efficiency of 94-96% during the entire experiment. In the LCS covers, the CH(4) removal efficiencies varied with the fluctuation of CH(4) influent flux, even negative ones occurred due to the storage of CH(4) in the soil porosities after the high CH(4) influent flux of ~137 gm(-2) d(-1). The lower concentrations of O(2) and CH(4) as well as the higher concentration of CO(2) were observed in the WBS covers than those in the LCS covers. The highest CH(4) oxidation rates of the two types of soil covers both occurred in the bottom layer (20-30 cm). Compared to the LCS, the WBS showed higher CH(4) oxidation activity and methane monooxygenase activity over the course of the experiment. Overall, this study indicated the WBS worked well for the fluctuation of CH(4) influent flux during landfill stabilization. Copyright © 2012 Elsevier Ltd. All rights reserved.

Review of Concrete Biodeterioration in Relation to Buried Nuclear Waste

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

Turick, C; Berry, C.

Long-term storage of low level radioactive material in below ground concrete disposal units (DUs) (Saltstone Disposal Facility) is a means of depositing wastes generated from nuclear operations of the U.S. Department of Energy. Based on the currently modeled degradation mechanisms, possible microbial induced effects on the structural integrity of buried low level wastes must be addressed. Previous international efforts related to microbial impacts on concrete structures that house low level radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the recent research in thismore » field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete vaults housing stored wastes and the wastes themselves. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources like components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The results of this review suggest that microbial activity in Saltstone, (grouted low level radioactive waste) is unlikely due to very high pH and osmotic pressure. Biodegradation of the concrete vaults housing the radioactive waste however, is a possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Results from this review point to parameters to focus on for modeling activities and also, possible options for mitigation that would minimize concrete biodegradation. In addition, key chemical components that drive

Development of the Use of Alternative Cements for the Treatment of Intermediate Level Waste

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

Hayes, M.; Godfrey, I.H.

2007-07-01

This paper describes initial development studies undertaken to investigate the potential use of alternative, non ordinary Portland cement (OPC) based encapsulation matrices to treat historic legacy wastes within the UK's Intermediate Level Waste (ILW) inventory. Currently these wastes are encapsulated in composite OPC cement systems based on high replacement with blast furnace slag of pulverised fuel ash. However, the high alkalinity of these cements can lead to high corrosion rates with reactive metals found in some wastes releasing hydrogen and forming expansive corrosion products. This paper therefore details preliminary results from studies on two commercial products, calcium sulfo-aluminate (CSA) andmore » magnesium phosphate (MP) cement which react with a different hydration chemistry, and which may allow wastes containing these metals to be encapsulated with lower reactivity. The results indicate that grouts can be formulated from both cements over a range of water contents and reactant ratios that have significantly improved fluidity in comparison to typical OPC cements. All designed mixes set in 24 hours with zero bleed and the pH values in the plastic state were in the range 10-11 for CSA and 5-7 for MP cements. In addition, a marked reduction in aluminium corrosion rate has been observed in both types of cements compared to a composite OPC system. These results therefore provide encouragement that both cement types can provide a possible alternative to OPC in the immobilisation of reactive wastes, however further investigation is needed. (authors)« less

Determining the release of radionuclides from tank waste residual solids. FY2015 report

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

King, William D.; Hobbs, David T.

Methodology development for pore water leaching studies has been continued to support Savannah River Site High Level Waste tank closure efforts. For FY2015, the primary goal of this testing was the achievement of target pH and Eh values for pore water solutions representative of local groundwater in the presence of grout or grout-representative (CaCO 3 or FeS) solids as well as waste surrogate solids representative of residual solids expected to be present in a closed tank. For oxidizing conditions representative of a closed tank after aging, a focus was placed on using solid phases believed to be controlling pH andmore » E h at equilibrium conditions. For three pore water conditions (shown below), the target pH values were achieved to within 0.5 pH units. Tank 18 residual surrogate solids leaching studies were conducted over an E h range of approximately 630 mV. Significantly higher Eh values were achieved for the oxidizing conditions (ORII and ORIII) than were previously observed. For the ORII condition, the target Eh value was nearly achieved (within 50 mV). However, E h values observed for the ORIII condition were approximately 160 mV less positive than the target. E h values observed for the RRII condition were approximately 370 mV less negative than the target. Achievement of more positive and more negative E h values is believed to require the addition of non-representative oxidants and reductants, respectively. Plutonium and uranium concentrations measured during Tank 18 residual surrogate solids leaching studies under these conditions (shown below) followed the general trends predicted for plutonium and uranium oxide phases, assuming equilibrium with dissolved oxygen. The highest plutonium and uranium concentrations were observed for the ORIII condition and the lowest concentrations were observed for the RRII condition. Based on these results, it is recommended that these test methodologies be used to conduct leaching studies with actual Tank 18 residual

LEACHING BOUNDARY MOVEMENT IN SOLIDIFIED/STABILIZED WASTE FORMS

EPA Science Inventory

Investigation of the leaching of cement-based waste forms in acetic acid solutions found that acids attacked the waste form from the surface toward the center. A sharp leaching boundary was identified in every leached sample, using pH color indica- tors. The movement of the leach...

Improvement of fruit and vegetable waste anaerobic digestion performance and stability with co-substrates addition.

PubMed

Bouallagui, H; Lahdheb, H; Ben Romdan, E; Rachdi, B; Hamdi, M

2009-04-01

The effect of fish waste (FW), abattoir wastewater (AW) and waste activated sludge (WAS) addition as co-substrates on the fruit and vegetable waste (FVW) anaerobic digestion performance was investigated under mesophilic conditions using four anaerobic sequencing batch reactors (ASBR) with the aim of finding the better co-substrate for the enhanced performance of co-digestion. The reactors were operated at an organic loading rate of 2.46-2.51 g volatile solids (VS)l(-1)d(-1), of which approximately 90% were from FVW, and a hydraulic retention time of 10 days. It was observed that AW and WAS additions with a ratio of 10% VS enhanced biogas yield by 51.5% and 43.8% and total volatile solids removal by 10% and 11.7%, respectively. However FW addition led to improvement of the process stability, as indicated by the low VFAs/Alkalinity ratio of 0.28, and permitted anaerobic digestion of FVW without chemical alkali addition. Despite a considerable decrease in the C/N ratio from 34.2 to 27.6, the addition of FW slightly improved the gas production yield (8.1%) compared to anaerobic digestion of FVW alone. A C/N ratio between 22 and 25 seemed to be better for anaerobic co-digestion of FVW with its co-substrates. The most significant factor for enhanced FVW digestion performance was the improved organic nitrogen content provided by the additional wastes. Consequently, the occurrence of an imbalance between the different groups of anaerobic bacteria which may take place in unstable anaerobic digestion of FVW could be prevented.

New factors in the design, operation and performance of waste-stabilization ponds

PubMed Central

Marais, G. v. R.

1966-01-01

In the developing countries, the unit costs of waste-stabilization ponds are generally low. Moreover, in the tropics and subtropics, the environmental conditions are conducive to a high level of pond performance. In view of this, the theory, operation and performance of such ponds under these conditions have been studied. It is shown that the Hermann & Gloyna and Marais & Shaw theories of the degradation action in oxidation ponds can be integrated, and that account can be taken of the effect of the sludge layer. In Lusaka, Zambia, anaerobic conditions are much more likely to occur in summer than in winter, because of intense stratification. It is confirmed that a series of maturation or oxidation ponds is more efficient than a single pond of equivalent volume. When aqua privies and septic tanks are used as anaerobic pretreatment units, the area of the primary oxidation ponds can be reduced and there is less likelihood that anaerobic conditions will develop in them in summer. The use of self-topping aqua privies, discharging through sewers to oxidation ponds, has made possible the economic installation of water-carriage systems of waste disposal in low-cost high-density housing areas. In the oxidation ponds, typhoid bacteria appear to be more resistant than indicator organisms; helminths, cysts and ova settle out; there are no snails and, if peripheral vegetation is removed, mosquitos will not breed. PMID:5296235

Integrity assessment of grouted posttensioning cables and reinforced concrete of a nuclear containment building

NASA Astrophysics Data System (ADS)

Philipose, K.; Shenton, B.

2011-04-01

The Containment Buildings of CANDU Nuclear Generating Stations were designed to house nuclear reactors and process equipment and also to provide confinement of releases from a potential nuclear accident such as a Loss Of Coolant Accident (LOCA). To meet this design requirement, a post-tensioning system was designed to induce compressive stresses in the structure to counteract the internal design pressure. The CANDU reactor building at Gentilly-1 (G-1), Quebec, Canada (250 MWe) was built in the early 1970s and is currently in a decommissioned state. The structure at present is under surveillance and monitoring. In the year 2000, a field investigation was conducted as part of a condition assessment and corrosion was detected in some of the grouted post-tension cable strands. However, no further work was done at that time to determine the cause, nature, impact and extent of the corrosion. An investigation of the Gentilly-1 containment building is currently underway to assess the condition of grouted post-tensioning cables and reinforced concrete. At two selected locations, concrete and steel reinforcements were removed from the containment building wall to expose horizontal cables. Individual cable strands and reinforcement bars were instrumented and measurements were taken in-situ before removing them for forensic examination and destructive testing to determine the impact of ageing and corrosion. Concrete samples were also removed and tested in a laboratory. The purpose of the field investigation and laboratory testing, using this structure as a test bed, was also to collect material ageing data and to develop potential Nondestructive Examination (NDE) methods to monitor Containment Building Integrity. The paper describes the field work conducted and the test results obtained for concrete, reinforcement and post-tensioning cables.

ENGINEERING BULLETIN: SOLIDIFICATION/STABILIZATION OF ORGANICS AND INORGANICS

EPA Science Inventory

Solidification refers to techniques that encapsulate hazardous waste into a solid material of high structural integrity. Encapsulation involves either fine waste particles (microencapsulation) or a large block or container of wastes (macroencapsulation). Stabilization refe...

Leaching boundary movement in solidified/stabilized waste forms

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

Kuang Ye Cheng; Bishop, P.L.

1992-02-01

Investigation of the leaching of cement-based waste forms in acetic acid solutions found that acids attacked the waste form from the surface toward the center. A sharp leaching boundary was identified in every leached sample, using pH color indicators. The movement of the leaching boundary was found to be a single diffusion-controlled process.

Ray Grout | NREL

Science.gov Websites

cross flow from peta-scale, high-fidelity simulations in collaboration with the gas turbine industry. A stratified combustion in the stabilization of flames above a jet in cross flow. Earlier work involved using

[Effect of sodium carbonate assisted hydrothermal process on heavy metals stabilization in medical waste incinerator fly ash].

PubMed

Jin, Jian; Li, Xiao-dong; Chi, Yong; Yan, Jian-hua

2010-04-01

A sodium carbonate assisted hydrothermal process was induced to stabilize the fly ash from medical waste incinerator. The results showed that sodium carbonate assisted hydrothermal process reduced the heavy metals leachability of fly ash, and the heavy metal waste water from the process would not be a secondary pollution. The leachability of heavy metals studied in this paper were Cd 1.97 mg/L, Cr 1.56 mg/L, Cu 2.56 mg/L, Mn 17.30 mg/L, Ni 1.65 mg/L, Pb 1.56 mg/L and Zn 189.00 mg/L, and after hydrothermal process with the optimal experimental condition (Na2CO3/fly ash dosage = 5/20, reaction time = 8 h, L/S ratio = 10/1) the leachability reduced to < 0.02 mg/L for Cd, Cr, Cu, Mn, Ni, Pb, and 0.05 mg/L for Zn, according to GB 5085.3-2007. Meanwhile, the concentrations of heavy metals in effluent after hydrothermal process were less than 0.8 mg/L. The heavy metals leachability and concentration in effluent reduced with prolonged reaction time. Prolonged aging can affect the leachability of metals as solids become more crystalline, and heavy metals transferred inside of crystalline. The mechanism of heavy metal stabilization can be concluded to the co precipitation and adsorption effect of aluminosilicates formation, crystallization and aging process.

Determining Optimal Waste Volume From an Intravenous Catheter

PubMed Central

Baker, Rachel B.; Summer, Suzanne S.; Lawrence, Michelle; Shova, Amy; McGraw, Catherine A.; Khoury, Jane

2013-01-01

Waste is blood drawn from an intravenous (IV) catheter to remove saline before obtaining a blood sample. This study examines the minimum waste volume resulting in an undiluted sample. A repeated measures design was used. Investigators placed an IV catheter in 60 healthy adults and obtained samples at baseline and following waste volume ranging from 0.5 mL to 3 mL. A random effects mixed model was used to determine the stabilizing point. For sodium and glucose measurements, this stabilizing point was 1 mL of waste. Knowing that only 1 mL of waste is needed will prevent clinicians from obtaining extra waste and discarding blood needlessly. PMID:23455970

Analysis of the stability of high-solids anaerobic digestion of agro-industrial waste and sewage sludge.

PubMed

Aymerich, E; Esteban-Gutiérrez, M; Sancho, L

2013-09-01

The pilot-scale high-solids anaerobic digestion (HS-AD) of agro-industrial wastes and sewage sludge was analysed in terms of stability by monitoring the most common parameters used to check the performance of anaerobic digesters, i.e. Volatile Fatty Acids (VFA), ammonia nitrogen, pH, alkalinity and methane production. The results reflected similar evolution for the parameters analysed, except for an experiment that presented an unsuccessful start-up. The rest of the experiments ran successfully, although the threshold values proposed in the literature for the detection of an imbalance in wet processes were exceeded, proving the versatility of HS-AD to treat different wastes. The results evidence the need for understanding the dynamics of a high-solids system so as to detect periods of imbalance and to determine inhibitory levels for different compounds formed during anaerobic decomposition. Moreover, the findings presented here could be useful in developing an experimental basis to construct new control strategies for HS-AD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Leachates from solid wastes: chemical and eco(geno)toxicological differences between leachates obtained from fresh and stabilized industrial organic sludge.

PubMed

Chiochetta, Claudete G; Goetten, Luís C; Almeida, Sônia M; Quaranta, Gaetana; Cotelle, Sylvie; Radetski, Claudemir M

2014-01-01

The chemical and ecotoxicological characteristics of fresh and stabilized industrial organic sludge leachates were compared to obtain information regarding how the stabilization process can influence the ecotoxic potential of this industrial waste, which could be used for the amendment of degraded soil. Physicochemical analysis of the sludge leachates, as well as a battery of eco(geno)toxicity tests on bacteria, algae, daphnids, and higher plants (including Vicia faba genotoxicity test) and the determination of hydrolytic enzyme activity, was performed according to standard methods. The chemical comparison of the two types of leachate showed that the samples obtained from stabilized sludge had a lower organic content and higher metal content than leachates of the fresh sludge. The eco(geno)toxicological results obtained with aquatic organisms showed that the stabilized sludge leachate was more toxic than the fresh sludge leachate, both originating from the same industrial organic sludge sample. Nevertheless, phytotoxicity tests carried out with a reference peat soil irrigated with stabilized sludge leachate showed the same toxicity as the fresh sludge leachate. In the case of the industrial solid organic sludge studied, stabilization through a biodegradation process promoted a higher metal mobility/bioavailability/eco(geno)toxicity in the stabilized sludge leachate compared to the fresh sludge leachate.

Saltstone SDU6 Modeling Study

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

Lee, Si Y.; Hyun, Sinjae

2013-01-10

A new disposal unit, designated as Saltstone Disposal Unit 6 (SDU6), is being designed for support of site accelerated closure goals and salt waste projections identified in the new Liquid Waste System Plan. The unit is a cylindrical disposal cell of 375 ft in diameter and 43 ft in height, and it has a minimum 30 million gallons of capacity. SRNL was requested to evaluate the impact of an increased grout placement height on the flow patterns radially spread on the floor and to determine whether grout quality is impacted by the height. The primary goals of the work aremore » to develop the baseline Computational Fluid Dynamics (CFD) model and to perform the evaluations for the flow patterns of grout material in SDU6 as a function of elevation of grout discharge port and grout rheology. Two transient grout models have been developed by taking a three-dimensional multiphase CFD approach to estimate the domain size of the grout materials radially spread on the facility floor and to perform the sensitivity analysis with respect to the baseline design and operating conditions such as elevation height of the discharge port and fresh grout properties. For the CFD modeling calculations, air-grout Volume of Fluid (VOF) method combined with Bingham plastic and time-dependent grout models were used for examining the impact of fluid spread performance for the initial baseline configurations and to evaluate the impact of grout pouring height on grout quality. The grout quality was estimated in terms of the air volume fraction for the grout layer formed on the SDU6 floor, resulting in the change of grout density. The study results should be considered as preliminary scoping analyses since benchmarking analysis is not included in this task scope. Transient analyses with the Bingham plastic model were performed with the FLUENTTM code on the high performance parallel computing platform in SRNL. The analysis coupled with a transient grout aging model was performed by using ANSYS

Stabilization of tannery sludge by co-treatment with aluminum anodizing sludge and phytotoxicity of end-products.

PubMed

Pantazopoulou, E; Zebiliadou, O; Mitrakas, M; Zouboulis, A

2017-03-01

A global demand for efficient re-utilization of produced solid wastes, which is based on the principles of re-use and recycling, results to a circular economy, where one industry's waste becomes another's raw material and it can be used in a more efficient and sustainable way. In this study, the influence of a by-product addition, such as aluminum anodizing sludge, on tannery waste (air-dried sludge) stabilization was examined. The chemical characterization of tannery waste leachate, using the EN 12457-2 standard leaching test, reveals that tannery waste cannot be accepted even in landfills for hazardous wastes, according to the EU Decision 2003/33/EC. The stabilization of tannery waste was studied applying different ratios of tannery waste and aluminum anodizing sludge, i.e. 50:50, 60:40, 70:30 and 80:20 ratios respectively. Subsequently, the stabilization rate of the qualified as optimum homogenized mixture of 50:50 ratio was also tested during time (7, 15 and 30days). Moreover, this stabilized product was subjected to phytotoxicity tests using the Lepidium sativum, Sinapis alba and Sorghum saccharatum seeds. The experimental results showed that aluminum anodizing sludge managed to stabilize effectively chromium and organic content of tannery waste, which are the most problematic parameters influencing its subsequent disposal. As a result, tannery waste stabilized with the addition of aluminum anodizing sludge at 50:50 ratio can be accepted in non-hazardous waste landfills, as chromium and dissolved organic carbon concentrations in the respective leachate are below the relevant regulation limits, while the stabilized waste shows decreased phytotoxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluating laser-driven Bremsstrahlung radiation sources for imaging and analysis of nuclear waste packages.

PubMed

Jones, Christopher P; Brenner, Ceri M; Stitt, Camilla A; Armstrong, Chris; Rusby, Dean R; Mirfayzi, Seyed R; Wilson, Lucy A; Alejo, Aarón; Ahmed, Hamad; Allott, Ric; Butler, Nicholas M H; Clarke, Robert J; Haddock, David; Hernandez-Gomez, Cristina; Higginson, Adam; Murphy, Christopher; Notley, Margaret; Paraskevoulakos, Charilaos; Jowsey, John; McKenna, Paul; Neely, David; Kar, Satya; Scott, Thomas B

2016-11-15

A small scale sample nuclear waste package, consisting of a 28mm diameter uranium penny encased in grout, was imaged by absorption contrast radiography using a single pulse exposure from an X-ray source driven by a high-power laser. The Vulcan laser was used to deliver a focused pulse of photons to a tantalum foil, in order to generate a bright burst of highly penetrating X-rays (with energy >500keV), with a source size of <0.5mm. BAS-TR and BAS-SR image plates were used for image capture, alongside a newly developed Thalium doped Caesium Iodide scintillator-based detector coupled to CCD chips. The uranium penny was clearly resolved to sub-mm accuracy over a 30cm(2) scan area from a single shot acquisition. In addition, neutron generation was demonstrated in situ with the X-ray beam, with a single shot, thus demonstrating the potential for multi-modal criticality testing of waste materials. This feasibility study successfully demonstrated non-destructive radiography of encapsulated, high density, nuclear material. With recent developments of high-power laser systems, to 10Hz operation, a laser-driven multi-modal beamline for waste monitoring applications is envisioned. Copyright © 2016. Published by Elsevier B.V.

Enhancement of poly(3-hydroxybutyrate) thermal and processing stability using a bio-waste derived additive.

PubMed

Persico, Paola; Ambrogi, Veronica; Baroni, Antonio; Santagata, Gabriella; Carfagna, Cosimo; Malinconico, Mario; Cerruti, Pierfrancesco

2012-12-01

Poly(3-hydroxybutyrate) (PHB) is a biodegradable polymer, whose applicability is limited by its brittleness and narrow processing window. In this study a pomace extract (EP), from the bio-waste of winery industry, was used as thermal and processing stabilizer for PHB, aimed to engineer a totally bio-based system. The results showed that EP enhanced the thermal stability of PHB, which maintained high molecular weights after processing. This evidence was in agreement with the slower decrease in viscosity over time observed by rheological tests. EP also affected the melt crystallization kinetics and the overall crystallinity extent. Finally, dynamic mechanical and tensile tests showed that EP slightly improved the polymer ductility. The results are intriguing, in view of the development of sustainable alternatives to synthetic polymer additives, thus increasing the applicability of bio-based materials. Moreover, the reported results demonstrated the feasibility of the conversion of an agro-food by-product into a bio-resource in an environmentally friendly and cost-effective way. Copyright © 2012 Elsevier B.V. All rights reserved.

Reuse of Boron Waste as an Additive in Road Base Material

PubMed Central

Zhang, Yutong; Guo, Qinglin; Li, Lili; Jiang, Ping; Jiao, Yubo; Cheng, Yongchun

2016-01-01

The amount of boron waste increases year by year. There is an urgent demand to manage it in order to reduce the environmental impact. In this paper, boron waste was reused as an additive in road base material. Lime and cement were employed to stabilize the waste mixture. Mechanical performances of stabilized mixture were evaluated by experimental methods. A compaction test, an unconfined compressive test, an indirect tensile test, a modulus test, a drying shrinkage test, and a frost resistance test were carried out. Results indicated that mechanical strengths of lime-stabilized boron waste mixture (LSB) satisfy the requirements of road base when lime content is greater than 8%. LSB can only be applied in non-frozen regions as a result of its poor frost resistance. The lime–cement-stabilized mixture can be used in frozen regions when lime and cement contents are 8% and 5%, respectively. Aggregate reduces the drying shrinkage coefficient effectively. Thus, aggregate is suggested for mixture stabilization properly. This work provides a proposal for the management of boron waste. PMID:28773539

Summary of Group Development and Testing for Single Shell Tank Closure at Hanford

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

Harbour, John, R.

2005-04-28

This report is a summary of the bench-scale and large scale experimental studies performed by Savannah River National Laboratory for CH2M HILL to develop grout design mixes for possible use in producing fill materials as a part of Tank Closure of the Single-Shell Tanks at Hanford. The grout development data provided in this report demonstrates that these design mixes will produce fill materials that are ready for use in Hanford single shell tank closure. The purpose of this report is to assess the ability of the proposed grout specifications to meet the current requirements for successful single shell tank closuremore » which will include the contracting of services for construction and operation of a grout batch plant. The research and field experience gained by SRNL in the closure of Tanks 17F and 20F at the Savannah River Site was leveraged into the grout development efforts for Hanford. It is concluded that the three Hanford grout design mixes provide fill materials that meet the current requirements for successful placement. This conclusion is based on the completion of recommended testing using Hanford area materials by the operators of the grout batch plant. This report summarizes the regulatory drivers and the requirements for grout mixes as tank fill material. It is these requirements for both fresh and cured grout properties that drove the development of the grout formulations for the stabilization, structural and capping layers.« less

Evaluation of Biodegradability of Waste Before and After Aerobic Treatment

NASA Astrophysics Data System (ADS)

Suchowska-Kisielewicz, Monika; Jędrczak, Andrzej; Sadecka, Zofia

2014-12-01

An important advantage of use of an aerobic biostabilization of waste prior to its disposal is that it intensifies the decomposition of the organic fraction of waste into the form which is easily assimilable for methanogenic microorganisms involved in anaerobic decomposition of waste in the landfill. In this article it is presented the influence of aerobic pre-treatment of waste as well as leachate recirculation on susceptibility to biodegradation of waste in anaerobic laboratory reactors. The research has shown that in the reactor with aerobically treated waste stabilized with recilculation conversion of the organic carbon into the methane is about 45% higher than in the reactor with untreated waste stabilized without recirculation.

Effects of trace element addition on process stability during anaerobic co-digestion of OFMSW and slaughterhouse waste.

PubMed

Moestedt, J; Nordell, E; Shakeri Yekta, S; Lundgren, J; Martí, M; Sundberg, C; Ejlertsson, J; Svensson, B H; Björn, A

2016-01-01

This study used semi-continuous laboratory scale biogas reactors to simulate the effects of trace-element addition in different combinations, while degrading the organic fraction of municipal solid waste and slaughterhouse waste. The results show that the combined addition of Fe, Co and Ni was superior to the addition of only Fe, Fe and Co or Fe and Ni. However, the addition of only Fe resulted in a more stable process than the combined addition of Fe and Co, perhaps indicating a too efficient acidogenesis and/or homoacetogenesis in relation to a Ni-deprived methanogenic population. The results were observed in terms of higher biogas production (+9%), biogas production rates (+35%) and reduced VFA concentration for combined addition compared to only Fe and Ni. The higher stability was supported by observations of differences in viscosity, intraday VFA- and biogas kinetics as well as by the 16S rRNA gene and 16S rRNA of the methanogens. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of solidification/stabilization effects of calcite between Australian and South Korean cements

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

Lee, Dongjin; Waite, T. David; Swarbrick, Gareth

2005-11-15

The differences in the effect of calcite on the strength and stability of Pb-rich wastes solidified and stabilized using Australian and South Korean ordinary Portland cements are examined in this study. Pb-rich waste stabilized using Australian OPC has been shown to possess both substantially higher unconfined compressive strength and lead immobilization ability than South Korean OPC as a result of its higher C{sub 3}S content and the associated enhanced degree of precipitation of lead on the surfaces of silicate phases present. Calcite addition is observed to have an accelerating effect on the OPC-induced solidification/stabilization of Pb-rich wastes as gauged bymore » the unconfined compressive strength and leachability of the solids formed. This effect is observed to be far more dramatic for South Korean OPC than for Australian OPC. Using scanning electron microscopy, waste stabilized with cement and calcite was observed to develop significantly greater proportions of hydrated crystals than wastes stabilized with cement alone. The results of X-ray diffraction studies have shown that the presence of calcite in South Korean OPC results in greater acceleration in the formation of portlandite than is the case for Australian OPC.« less

75 FR 39008 - Environmental Management Site-Specific Advisory Board, Idaho National Laboratory

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-07

... Dry Storage. Waste Area Group--7 Update. In-Situ Grouting. Comment Resolution--Environmental... meeting be announced in the Federal Register. DATES: Wednesday, July 14, 2010 8 a.m.-5 p.m. Opportunities... management in the areas of environmental restoration, waste management, and related activities. Tentative...

Stabilization of lead in an alkali-activated municipal solid waste incineration fly ash-Pyrophyllite-based system.

PubMed

Shiota, Kenji; Nakamura, Takafumi; Takaoka, Masaki; Aminuddin, Siti Fatimah; Oshita, Kazuyuki; Fujimori, Takashi

2017-10-01

This work focuses on the stabilization and speciation of lead (Pb) in a composite solid produced from an alkali-activated municipal solid waste incineration fly ash (MSWIFA)-pyophyllite-based system. The solid product was synthesized after mixtures of raw materials (dehydrated pyrophyllite, MSWIFA, 14 mol/L aqueous sodium hydroxide, and sodium silicate solution) were cured at 105 °C for 24 h. The product could reduce the leaching of Pb and the Pb concentration in the leachate was 7.0 × 10 -3 using the Japanese leaching test and 9.7 × 10 -4  mg/L using toxicity characteristics leaching procedure method, which satisfied the respective test criteria and successfully stabilized Pb in this system. The solid product had a compressive strength of 2 MPa and consisted mainly of crystalline phases. Scanning electron microscopy with X-ray analysis and X-ray absorption fine structure suggested that Pb was present along with Al, Si, and O, and that the atomic environment around the Pb was similar to that of PbSiO 3 . These results suggest that the alkali-activated MSWIFA-pyrophyllite-based system could be used to stabilize Pb in MSWIFA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mercury stabilization in chemically bonded phosphate ceramics

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

Wagh, Arun S.; Jeong, Seung-Young; Singh, Dileep

1997-07-01

We have investigated mercury stabilization in chemically bonded phosphate ceramic (CBPC) using four surrogate waste streams that represent U.S. Department of Energy (DOE) ash, soil, and two secondary waste streams resulting from the destruction of DOE`s high-organic wastes by the DETOX{sup SM} Wet Oxidation Process. Hg content in the waste streams was 0.1 to 0.5 wt.% (added as soluble salts). Sulfidation of Hg and its concurrent stabilization in the CBPC matrix yielded highly nonleachable waste forms. The Toxicity Characteristic Leaching Procedure showed that leaching levels were well below the U.S. Environmental Protection Agency`s regulatory limits. The American Nuclear Society`s ANSmore » 16.1 immersion test also gave very high leaching indices, indicating excellent retention of the contaminants. In particular, leaching levels of Hg in the ash waste form were below the measurement detection limit in neutral and alkaline water, negligibly low but measureable in the first 72 h of leaching in acid water, and below the detection limit after that. These studies indicate that the waste forms are stable in a wide range of chemical environments during storage. 9 refs., 5 tabs.« less

Stabilization of cesium in alkali-activated municipal solid waste incineration fly ash and a pyrophyllite-based system.

PubMed

Shiota, Kenji; Nakamura, Takafumi; Takaoka, Masaki; Aminuddin, Siti Fatimah; Oshita, Kazuyuki; Fujimori, Takashi

2017-11-01

Environmentally sound treatments are required to dispose of municipal solid waste incineration fly ash (MSWIFA) contaminated with radioactive cesium (Cs) from the Fukushima Daiichi nuclear power plant accident in Japan. This study focuses on the stabilization of Cs using an alkali-activated MSWIFA and pyophyllite-based system. Three composite solid products were synthesized after mixtures of raw materials (dehydrated pyrophyllite, MSWIFA, 14 mol/L aqueous sodium hydroxide, and sodium silicate solution) were cured at 105 °C for 24 h. Three types of MSWIFAs were prepared as raw fly ash, raw fly ash with 0.1% CsCl, and raw fly ash with 40% CsCl to understand the stabilization mechanism of Cs. Cs stabilization in two solid products was successful, with less than 6.9% leaching observed from two types tests, and was partly successful for the solid product with the highest concentration of Cs. X-ray diffraction showed that all of the solid products produced several crystalline phases, and that pollucite was formed in the highest Cs concentration product. The X-ray absorption fine structure and scanning electron microscopy with X-ray analysis suggested that most Cs species formed pollucite in the two solid products from MSWIFA with added CsCl. This system provides a technique for the direct stabilization of Cs in MSWIFA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Clay Improvement with Burned Olive Waste Ash

PubMed Central

Mutman, Utkan

2013-01-01

Olive oil is concentrated in the Mediterranean basin countries. Since the olive oil industries are incriminated for a high quantity of pollution, it has become imperative to solve this problem by developing optimized systems for the treatment of olive oil wastes. This study proposes a solution to the problem. Burned olive waste ash is evaluated for using it as clay stabilizer. In a laboratory, bentonite clay is used to improve olive waste ash. Before the laboratory, the olive waste is burned at 550°C in the high temperature oven. The burned olive waste ash was added to bentonite clay with increasing 1% by weight from 1% to 10%. The study consisted of the following tests on samples treated with burned olive waste ash: Atterberg Limits, Standard Proctor Density, and Unconfined Compressive Strength Tests. The test results show promise for this material to be used as stabilizer and to solve many of the problems associated with its accumulation. PMID:23766671

Application of electrochemical peroxidation (ECP) process for waste-activated sludge stabilization and system optimization using response surface methodology (RSM).

PubMed

Gholikandi, Gagik Badalians; Kazemirad, Khashayar

2018-03-01

In this study, the performance of the electrochemical peroxidation (ECP) process for removing the volatile suspended solids (VSS) content of waste-activated sludge was evaluated. The Fe 2+ ions required by the process were obtained directly from iron electrodes in the system. The performance of the ECP process was investigated in various operational conditions employing a laboratory-scale pilot setup and optimized by response surface methodology (RSM). According to the results, the ECP process showed its best performance when the pH value, current density, H 2 O 2 concentration and the retention time were 3, 3.2 mA/cm 2 , 1,535 mg/L and 240 min, respectively. In these conditions, the introduced Fe 2+ concentration was approximately 500 (mg/L) and the VSS removal efficiency about 74%. Moreover, the results of the microbial characteristics of the raw and the stabilized sludge demonstrated that the ECP process is able to remove close to 99.9% of the coliforms in the raw sludge during the stabilization process. The energy consumption evaluation showed that the required energy of the ECP reactor (about 1.8-2.5 kWh (kg VSS removed) -1 ) is considerably lower than for aerobic digestion, the conventional waste-activated sludge stabilization method (about 2-3 kWh (kg VSS removed) -1 ). The RSM optimization process showed that the best operational conditions of the ECP process comply with the experimental results, and the actual and the predicted results are in good conformity with each other. This feature makes it possible to predict the introduced Fe 2+ concentrations into the system and the VSS removal efficiency of the process precisely.

An Investigation on the Persistence of Uranium Hydride during Storage of Simulant Nuclear Waste Packages.

PubMed

Stitt, C A; Harker, N J; Hallam, K R; Paraskevoulakos, C; Banos, A; Rennie, S; Jowsey, J; Scott, T B

2015-01-01

Synchrotron X-rays have been used to study the oxidation of uranium and uranium hydride when encapsulated in grout and stored in de-ionised water for 10 months. Periodic synchrotron X-ray tomography and X-ray powder diffraction have allowed measurement and identification of the arising corrosion products and the rates of corrosion. The oxidation rates of the uranium metal and uranium hydride were slower than empirically derived rates previously reported for each reactant in an anoxic water system, but without encapsulation in grout. This was attributed to the grout acting as a physical barrier limiting the access of oxidising species to the uranium surface. Uranium hydride was observed to persist throughout the 10 month storage period and industrial consequences of this observed persistence are discussed.

Repair, Evaluation, Maintenance, and Rehabilitation Research Program. State-of-the-Art Procedures for Sealing Coastal Structures with Grouts and Concretes

DTIC Science & Technology

1989-04-01

the shape it had as it was ex- truded from the grout tube . Figure 3 shows the type of voids in which the ma- terial is expected to form a barrier...has promising characteristics for coastal engi- neering applications. Microfine Cement, a company which markets ultrafine ce- ment, claims the product...can penetrate fine sand, and is strong and durable with a 4- to 5-hr set time. Fifty percent of Microfine Cement’s particles are less than 4 microns

Stabilization of Pb and Cd contaminated soils and soil quality improvements using waste oyster shells.

PubMed

Ok, Yong Sik; Lim, Jung Eun; Moon, Deok Hyun

2011-02-01

Large amounts of oyster shells are produced as a by-product of shellfish farming in coastal regions without beneficial use options. Accordingly, this study was conducted to evaluate the potential for the use of waste oyster shells (WOS) containing a high amount of CaCO₃ to improve soil quality and to stabilize heavy metals in soil. To accomplish this, an incubation experiment was conducted to evaluate the ability of the addition of 1-5 wt% WOS to stabilize the Pb (total 1,246 mg/kg) and Cd (total 17 mg/kg) in a contaminated soil. The effectiveness of the WOS treatments was evaluated using various single extraction techniques. Soil amended with WOS was cured for 30 days complied with the Korean Standard Test method (0.1 M·HCl extraction). The Pb and Cd concentrations were less than the Korean warning and countermeasure standards following treatment with 5 wt% WOS. Moreover, the concentrations of Cd were greatly reduced in response to WOS treatment following extraction using 0.01 M·CaCl₂, which is strongly associated with phytoavailability. Furthermore, the soil pH and exchangeable Ca increased significantly in response to WOS treatment. Taken together, the results of this study indicated that WOS amendments improved soil quality and stabilized Pb and Cd in contaminated soil. However, extraction with 0.43 M·CH₃ COOH revealed that remobilization of heavy metals can occur when the soil reaches an acidic condition.

Co-disposal of electronic waste with municipal solid waste in bioreactor landfills.

PubMed

Visvanathan, C; Visvanthan, C; Yin, Nang Htay; Karthikeyan, Obuli P

2010-12-01

Three pilot scale lysimeters were adopted to evaluate the stability pattern and leaching potential of heavy metals from MSW landfills under the E-waste co-disposed condition. One lysimeter served as control and solely filled with MSW, whereas the other two lysimeters were provided with 10% and 25% of E-waste scraps (% by weight), respectively. The reactors were monitored over a period of 280 days at ambient settings with continuous leachate recirculation. Stabilization pattern of carbon appears to be more than 50% in all the three lysimeters with irrespective of their operating conditions. Iron and zinc concentrations were high in leachate during bioreactor landfill operation and correlating with the TCLP leachability test results. In contrast, Pb concentration was around <0.6 mg/L, but which showed maximum leaching potential under TCLP test conditions. But, no heavy metal accumulation was found with leachate recirculation practices in lysimeters. Mobility of the metal content from the E-waste was found to be amplified with the long term disposal or stabilization within landfills. The results showed that the TCLP test cannot be completely reliable tool for measuring long-term leachability of toxic substances under landfill condition; rather landfill lysimeter studies are necessary to get the real scenario. Copyright © 2010 Elsevier Ltd. All rights reserved.

Space disposal of nuclear wastes

NASA Technical Reports Server (NTRS)

Priest, C. C.; Nixon, R. F.; Rice, E. E.

1980-01-01

The DOE has been studying several options for nuclear waste disposal, among them space disposal, which NASA has been assessing. Attention is given to space disposal destinations noting that a circular heliocentric orbit about halfway between Earth and Venus is the reference option in space disposal studies. Discussion also covers the waste form, showing that parameters to be considered include high waste loading, high thermal conductivity, thermochemical stability, resistance to leaching, fabrication, resistance to oxidation and to thermal shock. Finally, the Space Shuttle nuclear waste disposal mission profile is presented.

Method of waste stabilization via chemically bonded phosphate ceramics

DOEpatents

Wagh, Arun S.; Singh, Dileep; Jeong, Seung-Young

1998-01-01

A method for regulating the reaction temperature of a ceramic formulation process is provided comprising supplying a solution containing a monovalent alkali metal; mixing said solution with an oxide powder to create a binder; contacting said binder with bulk material to form a slurry; and allowing the slurry to cure. A highly crystalline waste form is also provided consisting of a binder containing potassium and waste substrate encapsulated by the binder.

An Investigation on the Persistence of Uranium Hydride during Storage of Simulant Nuclear Waste Packages

PubMed Central

Harker, N. J.; Hallam, K. R.; Paraskevoulakos, C.; Banos, A.; Rennie, S.; Jowsey, J.

2015-01-01

Synchrotron X-rays have been used to study the oxidation of uranium and uranium hydride when encapsulated in grout and stored in de-ionised water for 10 months. Periodic synchrotron X-ray tomography and X-ray powder diffraction have allowed measurement and identification of the arising corrosion products and the rates of corrosion. The oxidation rates of the uranium metal and uranium hydride were slower than empirically derived rates previously reported for each reactant in an anoxic water system, but without encapsulation in grout. This was attributed to the grout acting as a physical barrier limiting the access of oxidising species to the uranium surface. Uranium hydride was observed to persist throughout the 10 month storage period and industrial consequences of this observed persistence are discussed. PMID:26176551

Integrating EDDS-enhanced washing with low-cost stabilization of metal-contaminated soil from an e-waste recycling site.

PubMed

Beiyuan, Jingzi; Tsang, Daniel C W; Ok, Yong Sik; Zhang, Weihua; Yang, Xin; Baek, Kitae; Li, Xiang-Dong

2016-09-01

While chelant-enhanced soil washing has been widely studied for metal extraction from contaminated soils, there are concerns about destabilization and leaching of residual metals after remediation. This study integrated 2-h soil washing enhanced by biodegradable ethylenediaminedisuccinic acid (EDDS) and 2-month stabilization using agricultural waste product (soybean stover biochar pyrolyzed at 300 and 700 °C), industrial by-product (coal fly ash (CFA)), and their mixture. After integration with 2-month stabilization, the leachability and mobility of residual metals (Cu, Zn, and Pb) in the field-contaminated soil were significantly reduced, especially for Cu, in comparison with 2-h EDDS washing alone. This suggested that the metals destabilized by EDDS-washing could be immobilized by subsequent stabilization with biochar and CFA. Moreover, when the remediation performance was evaluated for phytoavailability and bioaccessibility, prior EDDS washing helped to achieve a greater reduction in the bioavailable fraction of metals than sole stabilization treatment. This was probably because the weakly-bound metals were first removed by EDDS washing before stabilization. Both individual and combined applications of biochar and CFA showed comparable effectiveness regardless of the difference in material properties, possibly due to the high level of amendments (150 ton ha(-1)). Based on the mobility and bioaccessibility results, the estimated human health risk (primarily resulting from Pb) could be mitigated to an acceptable level in water consumption pathway or reduced by half in soil ingestion pathway. These results suggest that an integration of EDDS washing with soil stabilization can alleviate post-remediation impacts of residual metals in the treated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Method of waste stabilization via chemically bonded phosphate ceramics

DOEpatents

Wagh, A.S.; Singh, D.; Jeong, S.Y.

1998-11-03

A method for regulating the reaction temperature of a ceramic formulation process is provided comprising supplying a solution containing a monovalent alkali metal; mixing said solution with an oxide powder to create a binder; contacting said binder with bulk material to form a slurry; and allowing the slurry to cure. A highly crystalline waste form is also provided consisting of a binder containing potassium and waste substrate encapsulated by the binder. 3 figs.

Select geotechnical properties of a lime stabilized expansive soil amended with bagasse ash and coconut shell powder

NASA Astrophysics Data System (ADS)

James, Jijo; Pandian, P. Kasinatha

2018-03-01

Lime stabilization has been and still is one of the most preferred methods for stabilization of expansive soils. However, in the recent times, utilization of solid waste materials in soil stabilization has gained prominence as an effective means to manage wastes generated from various sources. In this work, an attempt has been made to utilize waste materials from two sources as auxiliary additives to lime in the stabilization of an expansive soil. Bagasse ash (BA), a waste by-product from the sugar industry and Coconut shell powder (CSP), a processed waste obtained from left over coconut shells of oil extraction industry were used as auxiliary additives. An expansive soil obtained from a local field was subjected to chemical, mineral, microstructural and geotechnical characterization in the laboratory and stabilized using 3% lime. The waste materials were subjected to chemical, mineral and microstructural characterization. The stabilization process was amended with four different contents viz. 0.25%, 0.5%, 1% and 2% of BA and CSP separately and the effect of the amendment was studied on the unconfined compressive strength (UCS), plasticity, swell-shrink and microstructural characteristics of the expansive soil. The results of the study indicated that BA amendment of lime stabilization performed better than CSP in improving the UCS, plasticity, swell-shrink and microstructure of the lime stabilized expansive soil.

Anaerobic digestion of food waste stabilized by lime mud from papermaking process.

PubMed

Zhang, Jishi; Wang, Qinqing; Zheng, Pengwei; Wang, Yusong

2014-10-01

The effects of lime mud from papermaking process (LMP) addition as buffer agent and inorganic nutrient on the anaerobic digestion stability of food waste (FW) were investigated under mesophilic conditions with the aim of avoiding volatile fatty acids accumulation, and inorganic elements deficiency. When LMP concentration ranged from 6.0 to 10g/L, the FW anaerobic digestion could maintain efficient and stable state. These advantages are attributed to the existence of Ca, Na, Mg, K, Fe, and alkaline substances that favor the methanogenic process. The highest CH4 yield of 272.8mL/g-VS was obtained at LMP and VS concentrations of 10.0 and 19.8g/L, respectively, with the corresponding lag-phase time of 3.84d and final pH of 8.4. The methanogens from residue digestates mainly consisted of Methanobrevibacter, coccus-type and sarcina-type methanogens with LMP addition compared to Methanobacteria in control. However, higher concentration of LMP inhibited methanogenic activities and methane production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of scale and Froude number on the hydraulics of waste stabilization ponds.

PubMed

Vieira, Isabela De Luna; Da Silva, Jhonatan Barbosa; Ide, Carlos Nobuyoshi; Janzen, Johannes Gérson

2018-01-01

This paper presents the findings from a series of computational fluid dynamics simulations to estimate the effect of scale and Froude number on hydraulic performance and effluent pollutant fraction of scaled waste stabilization ponds designed using Froude similarity. Prior to its application, the model was verified by comparing the computational and experimental results of a model scaled pond, showing good agreement and confirming that the model accurately reproduces the hydrodynamics and tracer transport processes. Our results showed that the scale and the interaction between scale and Froude number has an effect on the hydraulics of ponds. At 1:5 scale, the increase of scale increased short-circuiting and decreased mixing. Furthermore, at 1:10 scale, the increase of scale decreased the effluent pollutant fraction. Since the Reynolds effect cannot be ignored, a ratio of Reynolds and Froude numbers was suggested to predict the effluent pollutant fraction for flows with different Reynolds numbers.

AN EVALUATION OF FACTORS AFFECTING THE SOLIDIFICATION/STABILIZATION OF HEAVY METAL SLUDGE

EPA Science Inventory

Solidification/stabilization (SIS) of hazardous waste involves mixing the waste with a binder material to enhance the physical properties of the waste and to immobilize contaminants that may be detrimental to the environment. Many hazardous wastes contain materials that are know...

High-level waste disposal, ethics and thermodynamics

NASA Astrophysics Data System (ADS)

Schwartz, Michael O.

2008-06-01

Moral philosophy applied to nuclear waste disposal can be linked to paradigmatic science. Simple thermodynamic principles tell us something about rightness or wrongness of our action. Ethical judgement can be orientated towards the chemical compatibility between waste container and geological repository. A container-repository system as close as possible to thermodynamic equilibrium is ethically acceptable. It aims at unlimited stability, similar to the stability of natural metal deposits within the Earth’s crust. The practicability of the guideline can be demonstrated.

Road Maintenance Experience Using Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization as Ground Rehabilitation

NASA Astrophysics Data System (ADS)

Fakhar, A. M. M.; Asmaniza, A.

2016-07-01

There are many types of ground rehabilation and improvement that can be consider and implement in engineering construction works for soil improvement in order to prevent road profile deformation in later stage. However, when comes to road maintenance especially on operated expressways, not all method can be apply directly as it must comply to opreation's working window and lane closure basis. Key factors that considering ideal proposal for ground rehabilitation are time, cost, quality and most importantly practicality. It should provide long lifespan structure in order to reduce continuous cycle of maintenance. Thus, this paper will present two approaches for ground rehabilitation, namely Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization. The first approach is an injection system which consists two-parts chemical grout of Isocynate and Polyol when mixed together within soil structure through injection will polymerized with volume expansion. The strong expansion of grouting causes significant compression and compacting of the surrounding soil and subsequently improve ground properties and uplift sunken structure. The later is a cold in-place recyclying whereby mixture process that combines in-situ soil materials, cement, white powder (alkaline) additive and water to produce hard yet flexible and durable ground layer that act as solid foundation with improved bearing capacity. The improvement of the mechanical behaviour of soil through these two systems is investigated by an extensive testing programme which includes in-situ and laboratory test in determining properties such as strength, stiffness, compressibility, bearing capacity, differential settlement and etc.

Nuclear waste management. Semiannual progress report, October 1982-March 1983

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

Chikalla, T.D.; Powell, J.A.

1983-06-01

This document is one of a series of technical progress reports designed to report radioactive waste management programs at the Pacific Northwest Laboratory. Accomplishments in the following programs are reported: waste stabilization; Materials Characterization Center; waste isolation; low-level waste management; remedial action; and supporting studies.

Stabilization Pond Operation and Maintenance Manual.

ERIC Educational Resources Information Center

Sexauer, Willard N.; Karn, Roger V.

This manual provides the waste stabilization pond operator with the basics necessary for the treatment of wastewater in stabilization ponds. The material is organized as a comprehensive guide that follows the normal operation and maintenance procedures from the time the wastewater enters the left station until it leaves the pond. A comprehensive…

Stabilization/solidification of radioactive salt waste by using xSiO2-yAl2O3-zP2O5 (SAP) material at molten salt state.

PubMed

Park, Hwan-Seo; Kim, In-Tae; Cho, Yong-Zun; Eun, Hee-Chul; Lee, Han-Soo

2008-12-15

The molten salt waste from the pyroprocess is one of the problematic wastes to directly apply a conventional process such as vitrification or ceramization. This study suggested a novel method using a reactive material for metal chlorides at a molten temperature of salt waste, and then converting them into manageable product at a high temperature. The inorganic composite, SAP (SiO2-Al2O3-P2O5), synthesized by a conventional sol-gel process has three or four distinctive domains that are bonded sequentially, Si-O-Si-O-A-O-P-O-P. The P-rich phase in the SAP composite is unstable for producing a series of reactive sites when in contact with a molten LiCl salt. After the reaction, metal aluminosilicate, metal aluminophosphate, metal phosphates and gaseous chlorines are generated. From this process, the volatile salt waste is stabilized and it is possible to apply a high temperature process. The reaction products were fabricated successfully by using a borosilicate glass with an arbitrary composition as a chemical binder. There was a low possibility for the valorization of radionuclides up to 1200 degrees C, based on the result of the thermo gravimetric analysis. The Cs and Sr leach rates by the PCT-A method were about 1 x 10(-3) g/(m2 day). For the final disposal of the problematic salt waste, this approach suggested the design concept of an effective stabilizer for metal chlorides and revealed the chemical route to the fabrication of monolithic wasteform by using a composite as an example. Using this method, we could obtain a higher disposal efficiency and lower waste volume, compared with the present immobilization methods.

Application of Hydrophilic Silanol-Based Chemical Grout for Strengthening Damaged Reinforced Concrete Flexural Members

PubMed Central

Ju, Hyunjin; Lee, Deuck Hang; Cho, Hae-Chang; Kim, Kang Su; Yoon, Seyoon; Seo, Soo-Yeon

2014-01-01

In this study, hydrophilic chemical grout using silanol (HCGS) was adopted to overcome the performance limitations of epoxy materials used for strengthening existing buildings and civil engineering structures. The enhanced material performances of HCGS were introduced, and applied to the section enlargement method, which is one of the typical structural strengthening methods used in practice. To evaluate the excellent structural strengthening performance of the HCGS, structural tests were conducted on reinforced concrete beams, and analyses on the flexural behaviors of test specimens were performed by modified partial interaction theory (PIT). In particular, to improve the constructability of the section enlargement method, an advanced strengthening method was proposed, in which the precast panel was directly attached to the bottom of the damaged structural member by HCGS, and the degree of connection of the test specimens, strengthened by the section enlargement method, were quantitatively evaluated by PIT-based analysis. PMID:28788708

Application of Hydrophilic Silanol-Based Chemical Grout for Strengthening Damaged Reinforced Concrete Flexural Members.

PubMed

Ju, Hyunjin; Lee, Deuck Hang; Cho, Hae-Chang; Kim, Kang Su; Yoon, Seyoon; Seo, Soo-Yeon

2014-06-23

In this study, hydrophilic chemical grout using silanol (HCGS) was adopted to overcome the performance limitations of epoxy materials used for strengthening existing buildings and civil engineering structures. The enhanced material performances of HCGS were introduced, and applied to the section enlargement method, which is one of the typical structural strengthening methods used in practice. To evaluate the excellent structural strengthening performance of the HCGS, structural tests were conducted on reinforced concrete beams, and analyses on the flexural behaviors of test specimens were performed by modified partial interaction theory (PIT). In particular, to improve the constructability of the section enlargement method, an advanced strengthening method was proposed, in which the precast panel was directly attached to the bottom of the damaged structural member by HCGS, and the degree of connection of the test specimens, strengthened by the section enlargement method, were quantitatively evaluated by PIT-based analysis.

High-solids anaerobic co-digestion of sewage sludge and food waste in comparison with mono digestions: stability and performance.

PubMed

Dai, Xiaohu; Duan, Nina; Dong, Bin; Dai, Lingling

2013-02-01

System stability and performance of high-solids anaerobic co-digestion of dewatered sludge (DS) and food waste (FW) in comparison with mono digestions were investigated. System stability was improved in co-digestion systems with co-substrate acting as a diluting agent to toxic chemicals like ammonia or Na(+). For high-solids digestion of DS, the addition of FW not only improved system stability but also greatly enhanced volumetric biogas production. For high-solids digestion of FW, the addition of DS could reduce Na(+) concentration and help maintain satisfactory stability during the conversion of FW into biogas. System performances of co-digestion systems were mainly determined by the mixing ratios of DS and FW. Biogas production and volatile solids (VSs) reduction in digestion of the co-mixture of DS and FW increased linearly with higher ratios of FW. A kinetic model, which aimed to forecast the performance of co-digestion and to assist reactor design, was developed from long-term semi-continuous experiments. Maximum VS reduction for DS and FW was estimated to be 44.3% and 90.3%, respectively, and first order constant k was found to be 0.17d(-1) and 0.50 d(-1), respectively. Experimental data of co-digestion were in good conformity to the predictions of the model. Copyright © 2012 Elsevier Ltd. All rights reserved.

Implementation plan for underground waste storage tank surveillance and stabilization improvements

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

Dukelow, G.T.; Maupin, V.D.; Mihalik, L.A.

1989-04-01

Several studies have addressed the need to upgrade the methods currently used for surveillance of underground waste storage tanks, particularly single-shell tanks (SST), which are susceptible to leaks and intrusions. Fifty tasks were proposed to enhance the existing surveillance program; however, prudent budget management dictates that only the tasks with the highest potential for success be selected and funded. This plan identifies fourteen inexpensive improvements that may be implemented in less than two years. Recent developments stress the need to complete interim stabilization of these tanks more quickly than now budgeted and to identify methods to salvage or eliminate themore » interstitial liquid left behind after saltwell jet-pumping. The plan calls for the use of available resources to remove saltwell liquid from SSTs as rapidly as possible rather than committing to new surveillance technologies that might not lead to near-term improvements. This plan describes the selection criteria and provides cost estimates and schedules for implementing the recommendations of the task forces. The proposed improvements result in completion of jet-pumping in FY 1994, two years ahead of the current FY 1996 milestone. While the accelerated plan requires more funding in the early years, the total cost will be the same as completing the work in FY 1996.« less

IMPROVED WELL PLUGGING EQUIPMENT AND WASTE MANGEMENT TECHNIQUES EXCEED ALARA GOALS AT THE OAK RIDGE NATIONAL LABORATORY

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

Whiteside, R.; Pawlowicz, R.; Whitehead, L.

2002-02-25

In 2000, Bechtel Jacobs Company LLC (BJC) contracted Tetra Tech NUS, Inc. (TtNUS) and their sub-contractor, Texas World Operations, Inc. (TWO), to plug and abandon (P&A) 111 wells located in the Melton Valley area of Oak Ridge National Laboratory (ORNL). One hundred and seven of those wells were used to monitor fluid movement and subsurface containment of the low level radioactive liquid waste/grout slurry that was injected into the Pumpkin Valley Shale Formation, underlying ORNL. Four wells were used as hydrofracture injection wells to emplace the waste in the shale formation. Although the practice of hydrofracturing was and is consideredmore » by many to pose no threat to human health or the environment, the practice was halted in 1982 after the Federal Underground Injection Control regulations were enacted by United States Environmental Protection Agency (USEPA) making it necessary to properly close the wells. The work is being performed for the United States Department of Energy Oak Ridge Operations (DOE ORO). The project team is using the philosophy of minimum waste generation and the principles of ALARA (As Low As Reasonably Achievable) as key project goals to minimize personnel and equipment exposure, waste generation, and project costs. Achievement of these goals was demonstrated by the introduction of several new pieces of custom designed well plugging and abandonment equipment that were tested and used effectively during field operations. Highlights of the work performed and the equipment used are presented.« less

Foaming in simulated radioactive waste.

PubMed

Bindal, S K; Nikolov, A D; Wasan, D T; Lambert, D P; Koopman, D C

2001-10-01

Radioactive waste treatment process usually involves concentration of radionuclides before waste can be immobilized by storing it in stable solid form. Foaming is observed at various stages of waste processing like SRAT (sludge receipt and adjustment tank) and melter operations. This kind of foaming greatly limits the process efficiency. The foam encountered can be characterized as a three-phase foam that incorporates finely divided solids (colloidal particles). The solid particles stabilize foaminess in two ways: by adsorption of biphilic particles at the surfaces of foam lamella and by layering of particles trapped inside the foam lamella. During bubble generation and rise, solid particles organize themselves into a layered structure due to confinement inside the foam lamella, and this structure provides a barrier against the coalescence of the bubbles, thereby causing foaming. Our novel capillary force balance apparatus was used to examine the particle-particle interactions, which affect particle layer formation in the foam lamella. Moreover, foaminess shows a maximum with increasing solid particle concentration. To explain the maximum in foaminess, a study was carried out on the simulated sludge, a non-radioactive simulant of the radioactive waste sludge at SRS, to identify the parameters that affect the foaming in a system characterized by the absence of surface-active agents. This three-phase foam does not show any foam stability unlike surfactant-stabilized foam. The parameters investigated were solid particle concentration, heating flux, and electrolyte concentration. The maximum in foaminess was found to be a net result of two countereffects that arise due to particle-particle interactions: structural stabilization and depletion destabilization. It was found that higher electrolyte concentration causes a reduction in foaminess and leads to a smaller bubble size. Higher heating fluxes lead to greater foaminess due to an increased rate of foam lamella

Crystalline phase, microstructure, and aqueous stability of zirconolite-barium borosilicate glass-ceramics for immobilization of simulated sulfate bearing high-level liquid waste

NASA Astrophysics Data System (ADS)

Wu, Lang; Xiao, Jizong; Wang, Xin; Teng, Yuancheng; Li, Yuxiang; Liao, Qilong

2018-01-01

The crystalline phase, microstructure, and aqueous stability of zirconolite-barium borosilicate glass-ceramics with different content (0-30 wt %) of simulated sulfate bearing high-level liquid waste (HLLW) were evaluated. The sulfate phase segregation in vitrification process was also investigated. The results show that the glass-ceramics with 0-20 wt% of HLLW possess mainly zirconolite phase along with a small amount baddeleyite phase. The amount of perovskite crystals increases while the amount of zirconolite crystals decreases when the HLLW content increases from 20 to 30 wt%. For the samples with 20-30 wt% HLLW, yellow phase was observed during the vitrification process and it disappeared after melting at 1150 °C for 2 h. The viscosity of the sample with 16 wt% HLLW (HLLW-16) is about 27 dPa·s at 1150 °C. The addition of a certain amount (≤20 wt %) of HLLW has no significant change on the aqueous stability of glass-ceramic waste forms. After 28 days, the 90 °C PCT-type normalized leaching rates of Na, B, Si, and La of the sample HLLW-16 are 7.23 × 10-3, 1.57 × 10-3, 8.06 × 10-4, and 1.23 × 10-4 g·m-2·d-1, respectively.

Diffusion and Leaching Behavior of Radionuclides in Category 3 Waste Encasement Concrete and Soil Fill Material – Summary Report

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

Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.

2011-08-31

of diffusion of radionuclides may be affected by the formation of structural cracks in concrete, the carbonation of the buried waste form, and any potential effect of metallic iron (in the form of rebars) on the mobility of radionuclides. The radionuclides iodine-129 ({sup 129}I), technetium-99 ({sup 99}Tc), and uranium-238 ({sup 238}U) are identified as long-term dose contributors in Category 3 waste (Mann et al. 2001; Wood et al. 1995). Because of their anionic nature in aqueous solutions, {sup 129}I, {sup 99}Tc, and carbonate-complexed {sup 238}U may readily leach into the subsurface environment (Serne et al. 1989, 1992a, b, 1993, and 1995). The leachability and/or diffusion of radionuclide species must be measured to assess the long-term performance of waste grouts when contacted with vadose-zone pore water or groundwater. Although significant research has been conducted on the design and performance of cementitious waste forms, the current protocol conducted to assess radionuclide stability within these waste forms has been limited to the Toxicity Characteristic Leaching Procedure, Method 1311 Federal Registry (EPA 1992) and ANSI/ANS-16.1 leach test (ANSI 1986). These tests evaluate the performance under water-saturated conditions and do not evaluate the performance of cementitious waste forms within the context of waste repositories which are located within water-deficient vadose zones. Moreover, these tests assess only the diffusion of radionuclides from concrete waste forms and neglect evaluating the mechanisms of retention, stability of the waste form, and formation of secondary phases during weathering, which may serve as long-term secondary hosts for immobilization of radionuclides. The results of recent investigations conducted under arid and semi-arid conditions (Al-Khayat et al. 2002; Garrabrants et al. 2002; Garrabrants and Kosson 2003; Garrabrants et al. 2004; Gervais et al. 2004; Sanchez et al. 2002; Sanchez et al. 2003) provide valuable information

Thermal treatment of stabilized air pollution control residues in a waste incinerator pilot plant. Part 2: Leaching characteristics of bottom ashes.

PubMed

Baun, Dorthe L; Christensen, Thomas H; Bergfeldt, Brita; Vehlow, Jürgen; Mogensen, Erhardt P B

2004-02-01

With the perspective of generating only one solid residue from waste incineration, co-feeding of municipal solid waste and air pollution control residues stabilized by the Ferrox process was investigated in the TAMARA pilot plant incinerator as described in Bergfeldt et al. (Waste Management Research, 22, 49-57, 2004). This paper reports on leaching from the combined bottom ashes. Batch leaching test, pH-static leaching tests, availability tests and column leaching tests were used to characterize the leaching properties. The leaching properties are key information in the context of reuse in construction or in landfilling of the combined residue. In general, the combined bottom ashes had leaching characteristics similar to the reference bottom ash, which contained no APC residue. However, As and Pb showed slightly elevated leaching from the combined bottom ashes, while Cr showed less leaching. The investigated combined bottom ashes had contents of metals comparable to what is expected at steady state after continuous co-feeding of APC residues. Only Cd and Pb were partly volatilized (30-40%) during the incineration process and thus the combined bottom ashes had lower contents of Cd and Pb than expected at steady state. Furthermore, a major loss of Hg was, not surprisingly, seen and co-feeding of Ferrox-products together with municipal solid waste will require dedicated removal of Hg in the flue gas to prevent a build up of Hg in the system. In spite of this, a combined single solid residue from waste incineration seems to be a significant environmental improvement to current technology.

The removal of thermo-tolerant coliform bacteria by immobilized waste stabilization pond algae.

PubMed

Pearson, H W; Marcon, A E; Melo, H N

2011-01-01

This study investigated the potential of laboratory- scale columns of immobilized micro-algae to disinfect effluents using thermo-tolerant coliforms (TTC) as a model system. Cells of a Chlorella species isolated from a waste stabilization pond complex in Northeast Brazil were immobilized in calcium alginate, packed into glass columns and incubated in contact with TTC suspensions for up to 24 hours. Five to six log removals of TTC were achieved in 6 hours and 11 log removals in 12 hours contact time. The results were similar under artificial light and shaded sunlight. However little or no TTC removal occurred in the light in columns of alginate beads without immobilized algae present or when the immobilized algae were incubated in the dark suggesting that the presence of both algae and light were necessary for TTC decay. There was a positive correlation between K(b) values for TTC and increasing pH in the effluent from the immobilized algal columns within the range pH 7.2 and 8.9. The potential of immobilized algal technology for wastewater disinfection may warrant further investigation.

In-service Inspection of Radioactive Waste Tanks at the Savannah River Site – 15410

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

Wiersma, Bruce; Maryak, Matthew; Baxter, Lindsay

2015-01-12

Liquid radioactive wastes from the Savannah River Site (SRS) separation process are stored in large underground carbon steel tanks. The high level wastes are processed in several of the tanks and then transferred by piping to other site facilities for further processing before they are stabilized in a vitrified or grout waste form. Based on waste removal and processing schedules, many of the tanks will be required to be in service for times exceeding the initial intended life. Until the waste is removed from storage, transferred, and processed, the materials and structures of the tanks must maintain a confinement functionmore » by providing a barrier to the environment and by maintaining acceptable structural stability during design basis events, which include loadings from both normal service and abnormal (e.g., earthquake) conditions. A structural integrity program is in place to maintain the structural and leak integrity functions of these waste tanks throughout their intended service life. In-service inspection (ISI) is an essential element of a comprehensive structural integrity program for the waste tanks at the Savannah River Site (SRS). The ISI program was developed to determine the degree of degradation the waste tanks have experienced due to service conditions. As a result of the inspections, an assessment can be made of the effectiveness of corrosion controls for the waste chemistry, which precludes accelerated localized and general corrosion of the waste tanks. Ultrasonic inspections (UT) are performed to detect and quantify the degree of general wall thinning, pitting and cracking as a measure of tank degradation. The results from these inspections through 2013, for the 27 Type III/IIIA tanks, indicate no reportable in-service corrosion degradation in the primary tank (i.e., general, pitting, or cracking). The average wall thickness for all tanks remains above the manufactured nominal thickness minus 0.25 millimeter and the largest pit identified is

Construction of Fluid - solid Coupling Model with Improved Richards - BP & Its Engineering Application

NASA Astrophysics Data System (ADS)

Xie, Chengyu; Jia, Nan; Shi, Dongping; Lu, Hao

2017-10-01

In order to study the slurry diffusion law during grouting, Richards unsaturated-saturated model was introduced, the definition of the grouting model is clear, the Richards model control equation was established, And the BP neural network was introduced, the improved fluid-solid coupling model was constructed, Through the use of saturated - unsaturated seepage flow model, As well as the overflow boundary iterative solution of the mixed boundary conditions, the free surface is calculated. Engineering practice for an example, with the aid of multi - field coupling analysis software, the diffusion law of slurry was simulated numerically. The results show that the slurry diffusion rule is affected by grouting material, initial pressure and other factors. When the slurry starts, it flows in the cracks along the upper side of the grouting hole, when the pressure gradient is reduced to the critical pressure, that is, to the lower side of the flow, when the slurry diffusion stability, and ultimately its shape like an 8. The slurry is spread evenly from the overall point of view, from the grouting mouth toward the surrounding evenly spread, it gradually reaches saturation by non-saturation, and it is not a purely saturated flow, when the slurry spread and reach a saturated state, the diffusion time is the engineering grouting time.

Semi-dynamic leaching tests of nickel containing wastes stabilized/solidified with magnesium potassium phosphate cements.

PubMed

Torras, Josep; Buj, Irene; Rovira, Miquel; de Pablo, Joan

2011-02-28

Herein is presented a study on the long-term leaching behaviour of nickel containing wastes stabilized/solidified with magnesium potassium phosphate cements. Two different semi-dynamic leaching tests were carried out on monolithic materials: ANS 16.1 test with liquid-to-solid ratio (L/S) of 10 dm(3) kg(-1) and increasing renewal times, and ASTM C1308 test with liquid-to-solid ratio (L/S) of 100 dm(3) kg(-1) and constant renewal time of 1 day. ASTM C1308 provides a lower degree of saturation of the leachant with respect to the leached material. The effectiveness of magnesium potassium phosphate cements for the inertization of nickel was proved. XRD analyses showed the presence of bobierrite on the monolith's surface after the leaching test, which had not been detected prior to the leaching test. In addition, the calculated cumulative release of the main components of the stabilization matrix (Mg(2+), total P and K(+)) was represented versus time in logarithmic scale and it was determined if the leaching mechanism corresponds to diffusion. Potassium is released by diffusion, while total phosphorous and magnesium show dissolution. Magnesium release in ANS 16.1 is slowed down because of saturation of the leachant. Experimental results demonstrate the importance of L/S ratio and renewal times in semi-dynamic leaching tests. Copyright © 2010 Elsevier B.V. All rights reserved.

Simulation and analysis on ultrasonic testing for the cement grouting defects of the corrugated pipe

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

Qingbang, Han; Ling, Chen; Changping, Zhu

2014-02-18

The defects exist in the cement grouting process of prestressed corrugated pipe may directly impair the bridge safety. In this paper, sound fields propagation in concrete structures with corrugated pipes and the influence of various different defects are simulated and analyzed using finite element method. The simulation results demonstrate a much complex propagation characteristic due to multiple reflection, refraction and scattering, where the scattering signals caused by metal are very strong, while the signals scattered by an air bubble are weaker. The influence of defect both in time and frequency domain are found through deconvolution treatment. In the time domain,more » the deconvolution signals correspond to larger defect display a larger head wave amplitude and shorter arrive time than those of smaller defects; in the frequency domain, larger defect also shows a stronger amplitude, lower center frequency and lower cutoff frequency.« less

[Co-composting high moisture vegetable waste and flower waste in a sequential fed operation].

PubMed

Zhang, Xiangfeng; Wang, Hongtao; Nie, Yongfeng

2003-11-01

Co-composting of high moisture vegetable wastes (celery and cabbage) and flower wastes (carnation) were studied in a sequential fed bed. The preliminary materials of composting were celery and carnation wastes. The sequential fed materials of composting were cabbage wastes and were fed every 4 days. Moisture content of mixture materials was between 60% and 70%. Composting was done in an aerobic static bed of composting based temperature feedback and control via aeration rate regulation. Aeration was ended when temperature of the pile was about 40 degrees C. Changes of composting of temperature, aeration rate, water content, organic matter, ash, pH, volume, NH4(+)-N, and NO3(-)-N were studied. Results show that co-composting of high moisture vegetable wastes and flower wastes, in a sequential fed aerobic static bed based temperature feedback and control via aeration rate regulation, can stabilize organic matter and removal water rapidly. The sequential fed operation are effective to overcome the difficult which traditional composting cannot applied successfully where high moisture vegetable wastes in more excess of flower wastes, such as Dianchi coastal.

Optimization of waste combinations during in-vessel composting of agricultural waste.

PubMed

Varma, V Sudharsan; Kalamdhad, Ajay S; Kumar, Bimlesh

2017-01-01

In-vessel composting of agricultural waste is a well-described approach for stabilization of compost within a short time period. Although composting studies have shown the different combinations of waste materials for producing good quality compost, studies of the particular ratio of the waste materials in the mix are still limited. In the present study, composting was conducted with a combination of vegetable waste, cow dung, sawdust and dry leaves using a 550 L rotary drum composter. Application of a radial basis functional neural network was used to simulate the composting process. The model utilizes physico-chemical parameters with different waste materials as input variables and three output variables: volatile solids, soluble biochemical oxygen demand and carbon dioxide evolution. For the selected model, the coefficient of determination reached the high value of 0.997. The complicated interaction of agricultural waste components during composting makes it a nonlinear problem so it is difficult to find the optimal waste combinations for producing quality compost. Optimization of a trained radial basis functional model has yielded the optimal proportion as 62 kg, 17 kg and 9 kg for vegetable waste, cow dung and sawdust, respectively. The results showed that the predictive radial basis functional model described for drum composting of agricultural waste was well suited for organic matter degradation and can be successfully applied.

The management of arsenic wastes: problems and prospects.

PubMed

Leist, M; Casey, R J; Caridi, D

2000-08-28

Arsenic has found widespread use in agriculture and industry to control a variety of insect and fungicidal pests. Most of these uses have been discontinued, but residues from such activities, together with the ongoing generation of arsenic wastes from the smelting of various ores, have left a legacy of a large number of arsenic-contaminated sites. The treatment and/or removal of arsenic is hindered by the fact that arsenic has a variety of valence states. Arsenic is most effectively removed or stabilized when it is present in the pentavalent arsenate form. For the removal of arsenic from wastewater, coagulation, normally using iron, is the preferred option. The solidification/stabilization of arsenic is not such a clear-cut process. Factors such as the waste's interaction with the additives (e.g. iron or lime), as well as any effect on the cement matrix, all impact on the efficacy of the fixation. Currently, differentiation between available solidification/stabilization processes is speculative, partly due to the large number of differing leaching tests that have been utilized. Differences in the leaching fluid, liquid-to-solid ratio, and agitation time and method all impact significantly on the arsenic leachate concentrations. This paper reviews options available for dealing with arsenic wastes, both solid and aqueous through an investigation of the methods available for the removal of arsenic from wastewater as well as possible solidification/stabilization options for a variety of waste streams.

Method for primary containment of cesium wastes

DOEpatents

Angelini, Peter; Lackey, Walter J.; Stinton, David P.; Blanco, Raymond E.; Bond, Walter D.; Arnold, Jr., Wesley D.

1983-01-01

A method for producing a cesium-retentive waste form, characterized by a high degree of compositional stability and mechanical integrity, is provided by subjecting a cesium-loaded zeolite to heat under conditions suitable for stabilizing the zeolite and immobilizing the cesium, and coating said zeolite for sufficient duration within a suitable environment with at least one dense layer of pyrolytic carbon to seal therein said cesium to produce a final, cesium-bearing waste form. Typically, the zeolite is stabilized and the cesium immobilized in less than four hours by confinement within an air environment maintained at about 600.degree. C. Coatings are thereafter applied by confining the calcined zeolite within a coating environment comprising inert fluidizing and carbon donor gases maintained at 1,000.degree. C. for a suitable duration.

The Role of Ceramics in a Resurgent Nuclear Industry

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

Marra, J

2006-02-28

With fuel oil and natural gas prices near record highs and worldwide energy demands increasing at an alarming rate, there is growing interest in revitalization of the nuclear power industry within the United States and across the globe. Ceramic materials have long played a very important part in the commercial nuclear industry with applications throughout the entire fuel cycle; from fuel fabrication to waste stabilization. As the international community begins to look at advanced fuel cycles that minimize waste and increase proliferation resistance, ceramic materials will play an even larger role. Many of the advanced reactor concepts being evaluated operatemore » at high-temperature requiring the use of durable, heat-resistant materials. Ceramic fuels are being investigated for a variety of Generation IV reactor concepts. These include the traditional TRISO-coated particles as well as advanced inert-matrix fuels. In order to minimize wastes and legacy materials, ceramic processes are also being applied to fuel reprocessing operations. Ceramic materials continue to provide a vital contribution in ''closing the fuel cycle'' by stabilization of associated low-level and high-level wastes in highly durable grout, ceramics, and glass. In the next five years, programs that are currently in the conceptual phase will begin laboratory- and engineering-scale demonstrations. This will require production-scale demonstrations of several ceramic technologies from fuel form development to advanced stabilization methods. Within the next five to ten years, these demonstrations will move to even larger scales and will also include radioactive demonstrations of these advanced technologies. These radioactive demonstrations are critical to program success and will require advances in ceramic materials associated with nuclear energy applications.« less

Co-treatment of flotation waste, neutralization sludge, and arsenic-containing gypsum sludge from copper smelting: solidification/stabilization of arsenic and heavy metals with minimal cement clinker.

PubMed

Liu, De-Gang; Min, Xiao-Bo; Ke, Yong; Chai, Li-Yuan; Liang, Yan-Jie; Li, Yuan-Cheng; Yao, Li-Wei; Wang, Zhong-Bing

2018-03-01

Flotation waste of copper slag (FWCS), neutralization sludge (NS), and arsenic-containing gypsum sludge (GS), both of which are difficult to dispose of, are major solid wastes produced by the copper smelting. This study focused on the co-treatment of FWCS, NS, and GS for solidification/stabilization of arsenic and heavy metals with minimal cement clinker. Firstly, the preparation parameters of binder composed of FWCS, NS, and cement clinker were optimized to be FWCS dosage of 40%, NS dosage of 10%, cement clinker dosage of 50%, mill time of 1.5 h, and water-to-binder ratio of 0.25. On these conditions, the unconfined compressive strength (UCS) of the binder reached 43.24 MPa after hydration of 28 days. Then, the binder was used to solidify/stabilize the As-containing GS. When the mass ratio of binder-to-GS was 5:5, the UCS of matrix can reach 11.06 MPa after hydration of 28 days, meeting the required UCS level of MU10 brick in China. Moreover, arsenic and other heavy metals in FWCS, NS, and GS were effectively solidified or stabilized. The heavy metal concentrations in leachate were much lower than those in the limits of China standard leaching test (CSLT). Therefore, the matrices were potential to be used as bricks in some constructions. XRD analysis shows that the main hydration products of the matrix were portlandite and calcium silicate hydrate. These hydration products may play a significant role in the stabilization/solidification of arsenic and heavy metals.

Sequential anaerobic/aerobic digestion for enhanced sludge stabilization: comparison of the process performance for mixed and waste sludge [corrected].

PubMed

Tomei, M Concetta; Carozza, Nicola Antonello

2015-05-01

Sequential anaerobic-aerobic digestion has been demonstrated as a promising alternative for enhanced sludge stabilization. In this paper, a feasibility study of the sequential digestion applied to real waste activated sludge (WAS) and mixed sludge is presented. Process performance is evaluated in terms of total solid (TS) and volatile solid (VS) removal, biogas production, and dewaterability trend in the anaerobic and double-stage digested sludge. In the proposed digestion lay out, the aerobic stage was operated with intermittent aeration to reduce the nitrogen load recycled to the wastewater treatment plant (WWTP). Experimental results showed a very good performance of the sequential digestion process for both waste and mixed sludge, even if, given its better digestibility, higher efficiencies are observed for mixed sludge. VS removal efficiencies in the anaerobic stage were 48 and 50% for waste and mixed sludge, respectively, while a significant additional improvement of the VS removal of 25% for WAS and 45% for mixed sludge has been obtained in the aerobic stage. The post-aerobic stage, operated with intermittent aeration, was also efficient in nitrogen removal, providing a significant decrease of the nitrogen content in the supernatant: nitrification efficiencies of 90 and 97% and denitrification efficiencies of 62 and 70% have been obtained for secondary and mixed sludges, respectively. A positive effect due to the aerobic stage was also observed on the sludge dewaterability in both cases. Biogas production, expressed as Nm(3)/(kgVSdestroyed), was 0.54 for waste and 0.82 for mixed sludge and is in the range of values reported in the literature in spite of the low anaerobic sludge retention time of 15 days.

Short-term effects of sugarcane waste products from ethanol production plant as soil amendments on sugarcane growth and metal stabilization.

PubMed

Akkajit, Pensiri; DeSutter, Thomas; Tongcumpou, Chantra

2013-05-01

Numerous waste products have been widely studied and used as soil amendments and metal immobilizing agents. Waste utilization from ethanol production processes as soil amendments is one of the most promising and sustainable options to help utilize materials effectively, reduce waste disposal, and add value to byproducts. As a consequence, this present work carried out a four-month pot experiment of sugarcane (Saccharum officinarum L.) cultivation in Cd and Zn contaminated soil to determine the effect of three sugarcane waste products (boiler ash, filter cake and vinasse) as soil amendment on sugarcane growth, metal translocation and accumulation in sugarcane, and fractionation of Cd and Zn in soil by the BCR sequential extraction. Four treatments were tested: (1) non-amended soil; (2) 3% w/w boiler ash; (3) 3% w/w filter cake; and (4) a combination of 1.5% boiler ash and 1.5% vinasse (w/w). Our findings showed the improved biomass production of sugarcanes; 6 and 3-fold higher for the above ground parts (from 8.5 to 57.6 g per plant) and root (from 2.1 to 6.59 g per plant), respectively, as compared to non-amended soil. Although there was no significant difference in Cd and Zn uptake in sugarcane (mg kg(-1)) between the non-amended soil and the treated soils (0.44 to 0.52 mg Cd kg(-1) and 39.9 to 48.1 mg Zn kg(-1), respectively), the reduction of the most bioavailable Cd concentration (BCR1 + 2) in the treated soils (35.4-54.5%) and the transformation of metal into an insoluble fraction (BCR3) highlighted the beneficial effects of sugarcane waste-products in promoting the sugarcane growth and Cd stabilization in soil.

Stabilization of NaCl-containing cuttings wastes in cement concrete by in situ formed mineral phases.

PubMed

Filippov, Lev; Thomas, Fabien; Filippova, Inna; Yvon, Jacques; Morillon-Jeanmaire, Anne

2009-11-15

Disposal of NaCl-containing cuttings is a major environmental concern due to the high solubility of chlorides. The present work aims at reducing the solubility of chloride by encapsulation in low permeability matrix as well as lowering its solubility by trapping into low-solubility phases. Both the studied materials were cuttings from an oil-based mud in oil drillings containing about 50% of halite, and cuttings in water-based mud from gas drilling containing 90% of halite. A reduction in the amount of dissolved salt from 41 to 19% according to normalized leaching tests was obtained by addition of potassium ortho-phosphate in the mortar formula of oil-based cuttings, while the aluminium dihydrogeno-phosphate is even more efficient for the stabilization of water-based cuttings with a NaCl content of 90%. Addition of ortho-phosphate leads to form a continuous and weakly soluble network in the cement matrix, which reduces the release of salt. The formed mineralogical phases were apatite and hydrocalumite. These phases encapsulate the salt grains within a network, thus lowering its interaction with water or/and trap chloride into low-solubility phases. The tested approaches allow to develop a confinement process of NaCl-containing waste of various compositions that can be applied to wastes, whatever the salt content and the nature of the drilling fluids (water or oil).

System for Odorless Disposal of Human Waste

NASA Technical Reports Server (NTRS)

Jennings, Dave; Lewis, Tod

1987-01-01

Conceptual system provides clean, hygienic storage. Disposal system stores human wastes compactly. Releases no odor or bacteria and requires no dangerous chemicals or unpleasant handling. Stabilizes waste by natural process of biodegradation in which microbial activity eventually ceases and ordors and bacteria reduced to easily contained levels. Simple and reliable and needs little maintenance.

Cost Analysis of Remediation Systems for Depleted Uranium

DTIC Science & Technology

2014-04-01

situ stabilization and phytoremediation . In-situ stabilization includes the use of amend- ments, capping, and grouting to immobilize the contaminant in...its current location. Adding amendments to the soil solidifies the DU into insoluble particles. Phytoremediation is the use of plants to help reduce

Recovery and safer disposal of phosphate coating sludge by solidification/stabilization.

PubMed

Ucaroglu, Selnur; Talinli, Ilhan

2012-08-30

Solidification/stabilization (S/S) of automotive phosphate coating sludge (PS) containing potentially toxic heavy metals was studied. The hazardous characteristics of this waste were assessed according to both Turkish and U.S. Environmental Protection Agency (EPA) regulations for hazardous solid waste. Unconfined compressive strength (UCS) and leaching behavior tests of the solidified/stabilized product were performed. Solidification studies were conducted using Portland cement (PC) as the binder. UCS was found to decrease with increasing waste content. It was found that recovery of the waste for construction applications was possible when the waste content of the mortar was 20% and below, but solidification for safe disposal was achieved only when higher waste concentrations were added. Cu, Cr, Ni, Pb and Zn were found to be significantly immobilized by the solidification/stabilization process. Ni and Zn, which were present at particularly high concentrations (2.281 and 135.318 g/kg respectively) in the PS, had highest the retention levels (94.87% and 98.74%, respectively) in the PC mortars. The organic contaminants and heavy metals present in PS were determined to be immobilized by the S/S process in accordance with the BS 6920 standard. Thus, the potential for hazardous PS waste to adversely impact human health and the environment was effectively eliminated by the S/S procedure. We conclude that S/S-treated PS is safe for disposal in landfills, while recovery of S/S-treated PS constituents remains possible. Copyright © 2012 Elsevier Ltd. All rights reserved.

US Department of Energy Plutonium Stabilization and Immobilization Workshop, December 12-14, 1995: Final proceedings

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

NONE

1996-05-01

The purpose of the workshop was to foster communication within the technical community on issues surrounding stabilization and immobilization of the Department`s surplus plutonium and plutonium- contaminated wastes. The workshop`s objectives were to: build a common understanding of the performance, economics and maturity of stabilization and immobilization technologies; provide a system perspective on stabilization and immobilization technology options; and address the technical issues associated with technologies for stabilization and immobilization of surplus plutonium and plutonium- contaminated waste. The papers presented during this workshop have been indexed separately.

DEMONSTRATION BULLETIN: SOLIDIFICATION/STABILIZATION OF ORGANIC/INORGANIC CONTAMINANTS - SILICATE TECHNOLOGY CORPORATION

EPA Science Inventory

Silicate Technology Corporation's (STC's) technology for treating hazardous waste utilizes silicate compounds to stabilize organic and inorganic constituents in contaminated soils and sludges. STC has developed two groups of reagents: SOILSORB HM for treating wastes with inorgan...

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.

Alternative disposal options for transuranic waste

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

Loomis, G.G.

1994-12-31

Three alternative concepts are proposed for the final disposal of stored and retrieved buried transuranic waste. These proposed options answer criticisms of the existing U.S. Department of Energy strategy of directly disposing of stored transuranic waste in deep, geological salt formations at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico. The first option involves enhanced stabilization of stored waste by thermal treatment followed by convoy transportation and internment in the existing WIPP facility. This concept could also be extended to retrieved buried waste with proper permitting. The second option involves in-state, in situ internment using an encapsulating lensmore » around the waste. This concept applies only to previously buried transuranic waste. The third option involves sending stored and retrieved waste to the Nevada Test Site and configuring the waste around a thermonuclear device from the U.S. or Russian arsenal in a specially designed underground chamber. The thermonuclear explosion would transmute plutonium and disassociate hazardous materials while entombing the waste in a national sacrifice area.« less

Revegetation in abandoned quarries with landfill stabilized waste and gravels: water dynamics and plant growth - a case study

NASA Astrophysics Data System (ADS)

Zhang, Cheng-liang; Feng, Jing-jing; Rong, Li-ming; Zhao, Ting-ning

2017-11-01

Large amounts of quarry wastes are produced during quarrying. Though quarry wastes are commonly used in pavement construction and concrete production, in situ utilization during ecological restoration of abandoned quarries has the advantage of simplicity. In this paper, rock fragments 2-3 cm in size were mixed with landfill stabilized waste (LSW) in different proportions (LSW : gravel, RL), which was called LGM. The water content, runoff and plant growth under natural precipitation were monitored for 2 years using a runoff plot experiment. LGM with a low fraction of LSW was compacted to different degrees to achieve an appropriate porosity; water dynamics and plant growth of compacted LGM were studied in a field experiment. The results showed the following: (1) LGM can be used during restoration in abandoned quarries as growing material for plants. (2) RL had a significant effect on the infiltration and water-holding capacity of LGM and thus influenced the retention of precipitation, water condition and plant growth. LGM with RL ranging from 8:1 to 3:7 was suitable for plant growth, and the target species grew best when RL was 5:5. (3) Compaction significantly enhanced water content of LGM with a low RL of 2:8, but leaf water content of plants was lower or unchanged in the more compacted plots. Moderate compaction was beneficial to the survival and growth of Robinia pseudoacacia L. Platycladus orientalis (L.) Franco and Medicago sativa L. were not significantly affected by compaction, and they grew better under a high degree of compaction, which was disadvantageous for the uppermost layer of vegetation.

Leaching characteristics of copper flotation waste before and after vitrification.

PubMed

Coruh, Semra; Ergun, Osman Nuri

2006-12-01

Copper flotation waste from copper production using a pyrometallurgical process contains toxic metals such as Cu, Zn, Co and Pb. Because of the presence of trace amounts of these highly toxic metals, copper flotation waste contributes to environmental pollution. In this study, the leaching characteristics of copper flotation waste from the Black Sea Copper Works in Samsun, Turkey have been investigated before and after vitrification. Samples obtained from the factory were subjected to toxicity tests such as the extraction procedure toxicity test (EP Tox), the toxicity characteristic leaching procedure (TCLP) and the "method A" extraction procedure of the American Society of Testing and Materials. The leaching tests showed that the content of some elements in the waste before vitrification exceed the regulatory limits and cannot be disposed of in the present form. Therefore, a stabilization or inertization treatment is necessary prior to disposal. Vitrification was found to stabilize heavy metals in the copper flotation waste successfully and leaching of these metals was largely reduced. Therefore, vitrification can be an acceptable method for disposal of copper flotation waste.

Secondary Waste Form Down-Selection Data Package—Fluidized Bed Steam Reforming Waste Form

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

Qafoku, Nikolla; Westsik, Joseph H.; Strachan, Denis M.

2011-09-12

The Hanford Site in southeast Washington State has 56 million gallons of radioactive and chemically hazardous wastes stored in 177 underground tanks (ORP 2010). The U.S. Department of Energy (DOE), Office of River Protection (ORP), through its contractors, is constructing the Hanford Tank Waste Treatment and Immobilization Plant (WTP) to convert the radioactive and hazardous wastes into stable glass waste forms for disposal. Within the WTP, the pretreatment facility will receive the retrieved waste from the tank farms and separate it into two treated process streams. These waste streams will be vitrified, and the resulting waste canisters will be sentmore » to offsite (high-level waste [HLW]) and onsite (immobilized low-activity waste [ILAW]) repositories. As part of the pretreatment and ILAW processing, liquid secondary wastes will be generated that will be transferred to the Effluent Treatment Facility (ETF) on the Hanford Site for further treatment. These liquid secondary wastes will be converted to stable solid waste forms that will be disposed of in the Integrated Disposal Facility (IDF). To support the selection of a waste form for the liquid secondary wastes from WTP, Washington River Protection Solutions (WRPS) has initiated secondary waste form testing work at Pacific Northwest National Laboratory (PNNL). In anticipation of a down-selection process for a waste form for the Solidification Treatment Unit to be added to the ETF, PNNL is developing data packages to support that down-selection. The objective of the data packages is to identify, evaluate, and summarize the existing information on the four waste forms being considered for stabilizing and solidifying the liquid secondary wastes. At the Hanford Site, the FBSR process is being evaluated as a supplemental technology for treating and immobilizing Hanford LAW radioactive tank waste and for treating secondary wastes from the WTP pretreatment and LAW vitrification processes.« less

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

Pickenheim, B.; Hansen, E.; Leishear, R.

A 10-inch READCO mixer is used for mixing the premix (45 (wt%) fly ash, 45 wt% slag, and 10 wt% portland cement) with salt solution in the Saltstone Production Facility (SPF). The Saltstone grout free falls into the grout hopper which feeds the suction line leading to the Watson SPX 100 duplex hose pump. The Watson SPX 100 pumps the grout through approximately 1500 feet of piping prior to being discharged into the Saltstone Disposal Facility (SDF) vaults. The existing grout hopper has been identified by the Saltstone Enhanced Low Activity Waste Disposal (ELAWD) project for re-design. The current nominalmore » working volume of this hopper is 12 gallons and does not permit handling an inadvertent addition of excess dry feeds. Saltstone Engineering has proposed a new hopper tank that will have a nominal working volume of 300 gallons and is agitated with a mechanical agitator. The larger volume hopper is designed to handle variability in the output of the READCO mixer and process upsets without entering set back during processing. The objectives of this task involve scaling the proposed hopper design and testing the scaled hopper for the following processing issues: (1) The effect of agitation on radar measurement. Formation of a vortex may affect the ability to accurately measure the tank level. The agitator was run at varying speeds and with varying grout viscosities to determine what parameters cause vortex formation and whether measurement accuracy is affected. (2) A dry feeds over addition. Engineering Calculating X-ESR-Z-00017 1 showed that an additional 300 pounds of dry premix added to a 300 gallon working volume would lower the water to premix ratio (W/P) from the nominal 0.60 to 0.53 based on a Salt Waste Processing Facility (SWPF) salt simulant. A grout with a W/P of 0.53 represents the upper bound of grout rheology that could be processed at the facility. A scaled amount of dry feeds will be added into the hopper to verify that this is a recoverable

Modern technology for landfill waste placement

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

Hansen, D.L.

1995-12-31

The City of Albany, New York, together with the principals of Landfill Service Corporation, proposed in November 1991 to demonstrate the successful practice of biostabilized solid waste placement in the newly constructed, double composite lined Interim Landfill located at Rapp Road in the City of Albany. This is a small facility, only 12 acres in area, which is immediately adjacent to residential neighbors. Significant advancements have been made for the control of environmental factors (odors, vectors, litter) while successfully achieving waste stabilization and air space conservations goals. Also, the procedure consumes a significant quantity of landfill leachate. The benefits ofmore » this practice include a dramatic improvement in the orderlines of waste placement with significant reduction of windblown dust and litter. The biostabilization process also reduces the presence of typical landfill vectors such as flies, crows, seagulls and rodents. All of these factors can pose serious problems for nearby residents to the City of Albany`s Interim landfill site. The physically and biologically uniform character of the stabilized waste mass can result in more uniform future landfill settlement and gas production properties. This can allow for more accurate prediction of postclosure conditions and reduction or elimination of remedial costs attendant to post closure gross differential settlement. Recent research in Europe indicates that aerobic pretreatment of waste also reduces contaminant loading of leachate.« less

Comparison of slope stability in two Brazilian municipal landfills.

PubMed

Gharabaghi, B; Singh, M K; Inkratas, C; Fleming, I R; McBean, E

2008-01-01

The implementation of landfill gas to energy (LFGTE) projects has greatly assisted in reducing the greenhouse gases and air pollutants, leading to an improved local air quality and reduced health risks. The majority of cities in developing countries still dispose of their municipal waste in uncontrolled 'open dumps.' Municipal solid waste landfill construction practices and operating procedures in these countries pose a challenge to implementation of LFGTE projects because of concern about damage to the gas collection infrastructure (horizontal headers and vertical wells) caused by minor, relatively shallow slumps and slides within the waste mass. While major slope failures can and have occurred, such failures in most cases have been shown to involve contributory factors or triggers such as high pore pressures, weak foundation soil or failure along weak geosynthetic interfaces. Many researchers who have studied waste mechanics propose that the shear strength of municipal waste is sufficient such that major deep-seated catastrophic failures under most circumstances require such contributory factors. Obviously, evaluation of such potential major failures requires expert analysis by geotechnical specialists with detailed site-specific information regarding foundation soils, interface shearing resistances and pore pressures both within the waste and in clayey barrier layers or foundation soils. The objective of this paper is to evaluate the potential use of very simple stability analyses which can be used to study the potential for slumps and slides within the waste mass and which may represent a significant constraint on construction and development of the landfill, on reclamation and closure and on the feasibility of a LFGTE project. The stability analyses rely on site-specific but simple estimates of the unit weight of waste and the pore pressure conditions and use "generic" published shear strength envelopes for municipal waste. Application of the slope stability

STABILIZATION/SOLIDIFICATION OF CERCLA AND RCRA WASTES

EPA Science Inventory

This Handbook provides U.S. EPA regional staff responsible for reviewing CERCLA remedial action plans and RCRA permit applications with a tool for interpreting information on stabilization/solidification treatment. As a practical day-to-day reference guide, it will also provide t...

Tritium systems test assembly stabilization

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

Jasen, W. G.; Michelotti, R. A.; Anast, K. R.

The Tritium Systems Test Assembly (TSTA) was a facility dedicated to tritium technology Research and Development (R&D) primarily for future fusion power reactors. The facility was conceived in mid 1970's, operations commenced in early 1980's, stabilization and deactivation began in 2000 and were completed in 2003. The facility will remain in a Surveillance and Maintenance (S&M) mode until the Department of Energy (DOE) funds demolition of the facility, tentatively in 2009. A safe and stable end state was achieved by the TSTA Facility Stabilization Project (TFSP) in anticipation of long term S&M. At the start of the stabilization project, withmore » an inventory of approximately 140 grams of tritium, the facility was designated a Hazard Category (HC) 2 Non-Reactor Nuclear facility as defined by US Department of Energy standard DOE-STD-1027-92 (1997). The TSTA facility comprises a laboratory area, supporting rooms, offices and associated laboratory space that included more than 20 major tritium handling systems. The project's focus was to reduce the tritium inventory by removing bulk tritium, tritiated water wastes, and tritium-contaminated high-inventory components. Any equipment that remained in the facility was stabilized in place. All of the gloveboxes and piping were rendered inoperative and vented to atmosphere. All equipment, and inventoried tritium contamination, remaining in the facility was left in a safe-and-stable state. The project used the End Points process as defined by the DOE Office of Environmental Management (web page http://www.em.doe.- gov/deact/epman.htmtlo) document and define the end state required for the stabilization of TSTA Facility. The End Points process added structure that was beneficial through virtually all phases of the project. At completion of the facility stabilization project the residual tritium inventory was approximately 3,000 curies, considerably less than the 1.6-gram threshold for a HC 3 facility. TSTA is now designated

Reductive solidification/stabilization of chromate in municipal solid waste incineration fly ash by ascorbic acid and blast furnace slag.

PubMed

Zhou, Xian; Zhou, Min; Wu, Xian; Han, Yi; Geng, Junjun; Wang, Teng; Wan, Sha; Hou, Haobo

2017-09-01

Fly ash is a hazardous byproduct of municipal solid waste incineration (MSWI). Cementitious material that is based on ground-granulated blast furnace slag (GGBFS) has been tested and proposed as a binder to stabilize Pb, Cd, and Zn in MSWI fly ash (FA). Cr, however, still easily leaches from MSWI FA. Different reagents, such as ascorbic acid (VC), NaAlO 2 , and trisodium salt nonahydrate, were investigated as potential Cr stabilizers. The results of the toxicity characteristic leaching procedure (TCLP) showed that VC significantly improved the stabilization of Cr via the reduction of Cr(VI) to Cr(III). VC, however, could interfere with the hydration process. Most available Cr was transformed into stable Cr forms at the optimum VC content of 2 wt%. Cr leaching was strongly pH dependent and could be represented by a quintic polynomial model. The results of X-ray diffraction and scanning electron microscopy-energy dispersive analysis revealed that hollow spheres in raw FA were partially filled with hydration products, resulting in the dense and homogeneous microstructure of the solidified samples. The crystal structures of C-S-H and ettringite retained Zn and Cr ions. In summary, GGBFS-based cementitious material with the low addition of 2 wt% VC effectively immobilizes Cr-bearing MSWI FA. Copyright © 2017. Published by Elsevier Ltd.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1999-07-20

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1998-03-24

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Composition and process for the encapsulation and stabilization of radioactive hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1997-07-15

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a ``clean`` polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1998-03-24

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a ``clean`` polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Composition and process for the encapsulation and stabilization of radioactive hazardous and mixed wastes

DOEpatents

Kalb, Paul D.; Colombo, Peter

1997-01-01

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogenous molten matrix. The molten matrix may be directed in a "clean" polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment.

Composition and process for the encapsulation and stabilization of radioactive, hazardous and mixed wastes

DOEpatents

Kalb, P.D.; Colombo, P.

1999-07-20

The present invention provides a composition and process for disposal of radioactive, hazardous and mixed wastes. The present invention preferably includes a process for multibarrier encapsulation of radioactive, hazardous and mixed wastes by combining substantially simultaneously dry waste powder, a non-biodegradable thermoplastic polymer and an anhydrous additive in an extruder to form a homogeneous molten matrix. The molten matrix may be directed in a clean'' polyethylene liner, allowed to cool, thus forming a monolithic waste form which provides a multibarrier to the dispersion of wastes into the environment. 2 figs.

Benchmarking of DFLAW Solid Secondary Wastes and Processes with UK/Europe Counterparts

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

Brown, Elvie E.; Swanberg, David J.; Surman, J.

This report provides information and background on UK solid wastes and waste processes that are similar to those which will be generated by the Direct-Feed Low Activity Waste (DFLAW) facilities at Hanford. The aim is to further improve the design case for stabilizing and immobilizing of solid secondary wastes, establish international benchmarking and review possibilities for innovation.

Recycle of Zirconium from Used Nuclear Fuel Cladding: A Major Element of Waste Reduction

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

Collins, Emory D; DelCul, Guillermo D; Terekhov, Dmitri

2011-01-01

Feasibility tests were initiated to determine if the zirconium in commercial used nuclear fuel (UNF) cladding can be recovered in sufficient purity to permit re-use, and if the recovery process can be operated economically. Initial tests are being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Early results indicate that quantitative recovery can be accomplished and product contamination with alloy constituents can be controlled sufficiently to meet purification requirements. Future tests with actual radioactive UNF claddingmore » are planned. The objective of current research is to determine the feasibility of recovery and recycle of zirconium from used fuel cladding wastes. Zircaloy cladding, which contains 98+% of hafnium-free zirconium, is the second largest mass, on average {approx}25 wt %, of the components in used U.S. light-water-reactor fuel assemblies. Therefore, recovery and recycle of the zirconium would enable a large reduction in geologic waste disposal for advanced fuel cycles. Current practice is to compact or grout the cladding waste and store it for subsequent disposal in a geologic repository. This paper describes results of initial tests being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Future tests with actual radioactive UNF cladding are planned.« less

A Citizen's Guide to Solidification and Stabilization

EPA Pesticide Factsheets

This guide describes how solidification and stabilization refer to a group of cleanup methods that prevent or slow the release of harmful chemicals from wastes, such as contaminated soil, sediment, and sludge.

DEMONSTRATION BULLETIN: SOLIDIFICATION/STABILIZATION PROCESS, Hazcon, Inc.

EPA Science Inventory

The solidification/stabilization technology mixes hazardous wastes, cement, water and an additive called Chloranan. Chloranan, a nontoxic chemical, encapsulates organic molecules, rendering them ineffective in retarding or inhibiting solidification. This treatment technol...

APPLICATIONS ANALYSIS REPORT: SITE PROGRAM DEMONSTRATION TEST SOLIDITECH, INC. SOLIDIFICATION/ STABILIZATION PROCESS

EPA Science Inventory

This Applications Analysis Report evaluates the Soliditech, Inc., solidification/ stabilization process for the on-site treatment of waste materials. The Soliditech process mixes and chemically treats waste material with Urrichem (a proprietary reagent), additives, pozzolanic mat...

Delayed addition of nitrogen-rich substrates during composting of municipal waste: Effects on nitrogen loss, greenhouse gas emissions and compost stability.

PubMed

Nigussie, Abebe; Bruun, Sander; Kuyper, Thomas W; de Neergaard, Andreas

2017-01-01

Municipal waste is usually composted with an N-rich substrate, such as manure, to increase the N content of the product. This means that a significant amount of nitrogen can be lost during composting. The objectives of this study were (i) to investigate the effect of split addition of a nitrogen-rich substrate (poultry manure) on nitrogen losses and greenhouse gas emissions during composting and to link this effect to different bulking agents (coffee husks and sawdust), and (ii) to assess the effect of split addition of a nitrogen-rich substrate on compost stability and sanitisation. The results showed that split addition of the nitrogen-rich substrate reduced nitrogen losses by 9% when sawdust was used and 20% when coffee husks were used as the bulking agent. Depending on the bulking agent used, split addition increased cumulative N 2 O emissions by 400-600% compared to single addition. In contrast, single addition increased methane emissions by up to 50% compared to split addition of the substrate. Hence, the timing of the addition of the N-rich substrate had only a marginal effect on total non-CO 2 greenhouse gas emissions. Split addition of the N-rich substrate resulted in compost that was just as stable and effective at completely eradicating weed seeds as single addition. These findings therefore show that split addition of a nitrogen-rich substrate could be an option for increasing the fertilising value of municipal waste compost without having a significant effect on total greenhouse gas emissions or compost stability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Controlled Landfill Project in Yolo County, California for Environmental Benefits of Waste Stabilization and Minimization of Greenhouse Gas Emissions

NASA Astrophysics Data System (ADS)

Yazdani, R.; Augenstein, D.; Kieffer, J.; Cohen, K.

2003-12-01

The Department of Public Works of Yolo County, California, USA has been testing an advanced approach to landfill bioreactors, controlled (or "enhanced") landfilling, at its Yolo County Central Landfill site near Davis, CA, since 1994. Overall objectives have been the management of waste landfilling for: (1) rapid completion of total gas generation; (2) maximum, high-efficiency gas capture; (3) waste volume reduction; and (4) maximum greenhouse gas and carbon sequestration benefits. Methane generation is controlled and enhanced through carefully managed moisture additions, and by taking advantage of landfill temperature elevation. The generated landfill methane, an important greenhouse gas, is recovered with high efficiency through extraction from a porous recovery layer beneath a surface geomembrane cover. Instrumentation included a total of 56 moisture and 15 temperature sensors in the two cells, gas flow monitoring by positive displacement gas meters, and accurate quantification of liquid inputs and outputs. Gas composition, waste volume reduction, base hydrostatic head, and a range of environmental compliance parameters has been monitored since 1995. Partitioning gas tracer tests using the injection of two gases at dilute concentrations in the landfill have also been initiated to compute the fraction of pore space occupied by water between the points of tracer injection and tracer measurement. There has been rapid waste volume reduction in the enhanced cell that corresponds to the solids' reduction to gas. Monitoring is planned for the next several years, until stabilization parameters are determined complete. Encouraging performance is indicated by: (1) sensor data; (2) gas generation results; (3) data from landfill cores; and (4) decomposition-related indicators including rapid volume reduction. When data are synthesized, project results have attractive implications for new approaches to landfill management. Over seven-years, methane recoveries have averaged

Photostabilization of a landfill containing coal combustion waste

Treesearch

Christopher Barton; Donald Marx; Domy Adriano; Bon Jun Koo; Lee Newman; Stephen Czapka; John Blake

2005-01-01

The establishment of a vegetative cover to enhance evapotranspiration and control runoff and drainage was examined as a method for stabilizing a landfill containing coal combustion waste. Suitable plant species and pretreatment techniques in the form of amendments, tilling, and chemical stabilization were evaluated. A randomized plot design consisting of three...

Phytostabilization of a landfill containing coal combustion waste

Treesearch

Christopher Barton; Donald Marx; Domy Adriano; Bon Jun Koo; Lee Newman; Stephen Czapka; John Blake

2005-01-01

The establishment of a vegetative cover to enhance evapotranspiration and control runoff and drainage was examined as a method for stabilizing a landfill containing coal combustion waste. Suitable plant species and pretreatment techniques in the form of amendments, tilling, and chemical stabilization were evaluated. A randomized plot design consisting of three...

Minimally processed beetroot waste as an alternative source to obtain functional ingredients.

PubMed

Costa, Anne Porto Dalla; Hermes, Vanessa Stahl; Rios, Alessandro de Oliveira; Flôres, Simone Hickmann

2017-06-01

Large amounts of waste are generated by the minimally processed vegetables industry, such as those from beetroot processing. The aim of this study was to determine the best method to obtain flour from minimally processed beetroot waste dried at different temperatures, besides producing a colorant from such waste and assessing its stability along 45 days. Beetroot waste dried at 70 °C originates flour with significant antioxidant activity and higher betalain content than flour produced from waste dried at 60 and 80 °C, while chlorination had no impact on the process since microbiological results were consistent for its application. The colorant obtained from beetroot waste showed color stability for 20 days and potential antioxidant activity over the analysis period, thus it can be used as a functional additive to improve nutritional characteristics and appearance of food products. These results are promising since minimally processed beetroot waste can be used as an alternative source of natural and functional ingredients with high antioxidant activity and betalain content.

Co-treatment of fruit and vegetable waste in sludge digesters. An analysis of the relationship among bio-methane generation, process stability and digestate phytotoxicity.

PubMed

Di Maria, Francesco; Sordi, Alessio; Cirulli, Giuseppe; Gigliotti, Giovanni; Massaccesi, Luisa; Cucina, Mirko

2014-09-01

The co-digestion of a variable amount of fruit and vegetable waste in a waste mixed sludge digester was investigated using a pilot scale apparatus. The organic loading rate (OLR) was increased from 1.46 kg VS/m(3) day to 2.8 kg VS/m(3) day. The hydraulic retention time was reduced from 14 days to about 10 days. Specific bio-methane production increased from about 90 NL/kg VS to the maximum value of about 430 NL/kg VS when OLR was increased from 1.46 kg VS/m(3) day to 2.1 kg VS/m(3) day. A higher OLR caused an excessive reduction in the hydraulic retention time, enhancing microorganism wash out. Process stability evaluated by the total volatile fatty acids concentration (mg/l) to the alkalinity buffer capacity (eq. mg/l CaCO3) ratio (i.e. FOS/TAC) criterion was <0.1 indicating high stability for OLR <2.46 kg VS/m(3 )day. For higher OLR, FOS/TAC increased rapidly. Residual phytotoxicty of the digestate evaluated by the germination index (GI) (%) was quite constant for OLR<2.46 kg VS/m(3)day, which is lower than the 60% limit, indicating an acceptable toxicity level for crops. For OLR>2.46 kg VS/m(3) day, GI decreased rapidly. This corresponding trend between FOS/TAC and GI was further investigated by the definition of the GI ratio (GIR) parameter. Comparison between GIR and FOS/TAC suggests that GI could be a suitable criterion for evaluating process stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

EVALUATION OF WASTE STABILIZED BY THE SOLIDITECH SITE TECHNOLOGY

EPA Science Inventory

The Soliditech technology demonstration was conducted at the Imperial Oil Company/Champion Chemicals Superfund Site in Monmouth County, New Jersey. ontamination at this site includes PCBs, lead (with various other metals) and oil and grease. his process mixes the waste material w...

10 CFR 61.62 - Funding for disposal site closure and stabilization.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Section 61.62 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Financial Assurances § 61.62 Funding for disposal site closure and stabilization. (a) The... and stabilization, including: (1) Decontamination or dismantlement of land disposal facility...

10 CFR 61.62 - Funding for disposal site closure and stabilization.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Section 61.62 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Financial Assurances § 61.62 Funding for disposal site closure and stabilization. (a) The... and stabilization, including: (1) Decontamination or dismantlement of land disposal facility...

10 CFR 61.62 - Funding for disposal site closure and stabilization.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Section 61.62 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Financial Assurances § 61.62 Funding for disposal site closure and stabilization. (a) The... and stabilization, including: (1) Decontamination or dismantlement of land disposal facility...

10 CFR 61.62 - Funding for disposal site closure and stabilization.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Section 61.62 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Financial Assurances § 61.62 Funding for disposal site closure and stabilization. (a) The... and stabilization, including: (1) Decontamination or dismantlement of land disposal facility...

10 CFR 61.62 - Funding for disposal site closure and stabilization.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Section 61.62 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Financial Assurances § 61.62 Funding for disposal site closure and stabilization. (a) The... and stabilization, including: (1) Decontamination or dismantlement of land disposal facility...

Further contributions to the understanding of nitrogen removal in waste stabilization ponds.

PubMed

Bastos, R K X; Rios, E N; Sánchez, I A

2018-06-01

A set of experiments were conducted in Brazil in a pilot-scale waste stabilization pond (WSP) system (a four-maturation-pond series) treating an upflow anaerobic sludge blanket (UASB) reactor effluent. Over a year and a half the pond series was monitored under two flow rate conditions, hence also different hydraulic retention times and surface loading rates. On-site and laboratory trials were carried out to assess: (i) ammonia losses by volatilization using acrylic capture chambers placed at the surface of the ponds; (ii) organic nitrogen sedimentation rates using metal buckets placed at the bottom of the ponds for collecting settled particulate matter; (iii) nitrogen removal by algal uptake based on the nitrogen content of the suspended particulate matter in samples from the ponds' water column. In addition, nitrification and denitrification rates were measured in laboratory-based experiments using pond water and sediment samples. The pond system achieved high nitrogen removal (69% total nitrogen and 92% ammonia removal). The average total nitrogen removal rates varied from 10,098 to 3,849 g N/ha·d in the first and the last ponds, respectively, with the following fractions associated with the various removal pathways: (i) 23.5-45.6% sedimentation of organic nitrogen; (ii) 13.1-27.8% algal uptake; (iii) 1.2-3.1% ammonia volatilization; and (iv) 0.15-0.34% nitrification-denitrification.

Morphology and pH changes in leached solidified/stabilized waste forms

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

Cheng, K.Y.; Bishop, P.L.

1996-12-31

Leaching of cement-based waste forms in acetic acid solutions with different acidic strengths has been investigated in this work. The examination of the morphology and pH profile along the acid penetration route by an optical microscope and various pH color indicators is reported. A clear-cut leaching boundary, where the pH changes from below 6 in the leached surface layers to above 12 in the unleached waste form, was observed in every leached sample.

Importance of microscopy in durability studies of solidified and stabilized contaminated soils

USGS Publications Warehouse

Klich, I.; Wilding, L.P.; Drees, L.R.; Landa, E.R.

1999-01-01

Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or achieved in a laboratory warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical

Stress relaxation of grouted entirely large diameter B-GFRP soil nail

NASA Astrophysics Data System (ADS)

Li, Guo-wei; Ni, Chun; Pei, Hua-fu; Ge, Wan-ming; Ng, Charles Wang Wai

2013-08-01

One of the potential solutions to steel-corrosion-related problems is the usage of fiber reinforced polymer (FRP) as a replacement of steel bars. In the past few decades, researchers have conducted a large number of experimental and theoretical studies on the behavior of small size glass fiber reinforce polymer (GFRP) bars (diameter smaller than 20 mm). However, the behavior of large size GFRP bar is still not well understood. Particularly, few studies were conducted on the stress relaxation of grouted entirely large diameter GFRP soil nail. This paper investigates the effect of stress levels on the relaxation behavior of GFRP soil nail under sustained deformation ranging from 30% to 60% of its ultimate strain. In order to study the behavior of stress relaxation, two B-GFRP soil nail element specimens were developed and instrumented with fiber Bragg grating (FBG) strain sensors which were used to measure strains along the B-GFRP bars. The test results reveal that the behavior of stress relaxation of B-GFRP soil nail element subjected to pre-stress is significantly related to the elapsed time and the initial stress of relaxation procedure. The newly proposed model for evaluating stress relaxation ratio can substantially reflect the influences of the nature of B-GFRP bar and the property of grip body. The strain on the nail body can be redistributed automatically. Modulus reduction is not the single reason for the stress degradation.

SOLIDIFICATION/STABILIZATION: IS IT ALWAYS APPROPRIATE?

EPA Science Inventory

The findings of recent research and evaluation efforts are assessed to determine whether solidification/stabilization (S/S) has been properly and appropriately applied for different types of hazardous wastes. Results from these studies are mixed and, as a result, the need for pro...

Characterization and remediation of a mixed waste-contaminated site at Kirtland Air Force Base, New Mexico

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

Johnston, J.W.; Thacker, M.S.; DeWitt, C.B.

In the area of environmental restoration, one of the most challenging problems is the task of remediating mixed waste-contaminated sites. This paper discusses a successful Interim Corrective Measure (ICM) performed at a mixed waste-contaminated site on Kirtland Air Force Base (AFB) in Albuquerque, New Mexico. The site, known as RW-68, Cratering Area and Radium Dump/Slag Piles, was used during the late 1940s and early 1950s for the destruction and incineration of captured World War II aircraft. It contained 19 slag piles totaling approximately 150 tons of slag, ash, refractory brick, and metal debris. The piles were contaminated with radium-226 andmore » RCRA-characteristic levels of heavy metals. Therefore, the piles were considered mixed waste. To eliminate the threat to human health and the environment, an ICM of removal, segregation, stabilization, and disposal was conducted from October through December 1996. Approximately 120 cubic yards (cu yds) of mixed waste, 188 cu yds of low-level radioactive-contaminated soil, 1 cu yd of low-level radioactive-contaminated debris, 5 cu yds of RCRA-characteristic hazardous waste, and 45 tons of nonhazardous debris were stabilized and disposed of during the ICM. To render the RCRA metals and radionuclides insoluble, stabilization was performed on the mixed and RCRA-characteristic waste streams. All stabilized material was subjected to TCLP analysis to verify it no longer exhibited RCRA-characteristic properties. Radiological and geophysical surveys were conducted concurrently with site remediation activities. These surveys provided real-time documentation of site conditions during each phase of the ICM and confirmed successful cleanup of the site. The three radioactive waste streams, stabilized mixed waste, low-level radioactive-contaminated soil, and low-level radioactive-contaminated debris, were disposed of at the Envirocare low-level radioactive disposal facility.« less

EARTHSAWtm IN-SITU CONTAINMENT OF PITS AND TRENCHES

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

Ernest E. Carter, P.E.

2002-09-20

EarthSaw{trademark} is a proposed technology for construction of uniform high quality barriers under and around pits and trenches containing buried radioactive waste without excavating or disturbing the waste. The method works by digging a deep vertical trench around the perimeter of a site, filling that trench with high specific gravity grout sealant, and then cutting a horizontal bottom pathway at the base of the trench with a simple cable saw mechanism. The severed block of earth becomes buoyant in the grout and floats on a thick layer of grout, which then cures into an impermeable barrier. The ''Interim Report onmore » task 1 and 2'' which is incorporated into this report as appendix A, provided theoretical derivations, field validation of formulas, a detailed quantitative engineering description of the technique, engineering drawings of the hardware, and a computer model of how the process would perform in a wide variety of soil conditions common to DOE waste burial sites. The accomplishments of task 1 and 2 are also summarized herein Task 3 work product provides a comprehensive field test plan in Appendix B and a health and safety plan in Appendix C and proposal for a field-scale demonstration of the EarthSaw barrier technology. The final report on the subcontracted stress analysis is provided in Appendix D. A copy of the unified computer model is provided as individual non-functional images of each sheet of the spreadsheet and separately as a Microsoft Excel 2000 file.« less

Mercury leaching from hazardous industrial wastes stabilized by sulfur polymer encapsulation.

PubMed

López, Félix A; Alguacil, Francisco J; Rodríguez, Olga; Sierra, María José; Millán, Rocío

2015-01-01

European Directive 2013/39/EU records mercury as a priority hazardous substance. Regulation n° 2008/1102/EC banned the exportation of mercury and required the safe storage of any remaining mercury compounds. The present work describes the encapsulation of three wastes containing combinations of HgS, HgSe, HgCl2, HgO2, Hg3Se2Cl2, HgO and Hg(0), according to patent of Spanish National Research Council WO2011/029970A2. The materials obtained were subjected to leaching tests according to standards UNE-EN-12457 and CEN/TS 14405:2004. The results are compared with the criteria established in the Council Decision 2003/33/EC for the acceptance of waste at landfills. The Hg concentrations of all leachates were <0.01mgHg/kg for a liquid/solid ratio of 10l/kg. All three encapsulated materials therefore meet the requirements for storage in inert waste landfills. Copyright © 2014 Elsevier Ltd. All rights reserved.

Arsenic waste management: a critical review of testing and disposal of arsenic-bearing solid wastes generated during arsenic removal from drinking water.

PubMed

Clancy, Tara M; Hayes, Kim F; Raskin, Lutgarde

2013-10-01

Water treatment technologies for arsenic removal from groundwater have been extensively studied due to widespread arsenic contamination of drinking water sources. Central to the successful application of arsenic water treatment systems is the consideration of appropriate disposal methods for arsenic-bearing wastes generated during treatment. However, specific recommendations for arsenic waste disposal are often lacking or mentioned as an area for future research and the proper disposal and stabilization of arsenic-bearing waste remains a barrier to the successful implementation of arsenic removal technologies. This review summarizes current disposal options for arsenic-bearing wastes, including landfilling, stabilization, cow dung mixing, passive aeration, pond disposal, and soil disposal. The findings from studies that simulate these disposal conditions are included and compared to results from shorter, regulatory tests. In many instances, short-term leaching tests do not adequately address the range of conditions encountered in disposal environments. Future research directions are highlighted and include establishing regulatory test conditions that align with actual disposal conditions and evaluating nonlandfill disposal options for developing countries.

DEMONSTRATION BULLETIN - SOLIDIFICATION/ STABILIZATION PROCESS, SOLIDTECH, INC.

EPA Science Inventory

The Soliditech solidification/stabilization technology mixes hazardous waste materials in soils or sludges with pozzolanic material (cement, fly ash, or kiln dust), a proprietary additive called Urrichem, other proprietary additives, and water. The process is designed to aid ...

PREPARATION OF U-PLANT FOR FINAL DEMOLITION AND DISPOSAL - 12109E

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

FARABEE OA; HERZOG B; CAMERON C

2012-02-16

The U-Plant is one of the five major nuclear materials processing facilities at Hanford and was chosen as a pilot project to develop the modalities for closure of the other four facilities at Hanford and the rest of the Department of Energy (DOE) complex. The remedy for this facility was determined by a Record of Decision (ROD) pursuant to the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). That remedy was to 'Close in Place - Partially Demolished Structure'. The U-Plant facility is identified as the 221-U Building and is a large, concrete structure nominally 247m (810 ft)more » long, 20 M (66 ft) wide and 24 m (77 ft) high with approximately 9 m (30 ft) being below grade level. It is a robust facility with walls ranging from 0.9 m to 2.7 m (3 ft to 9 ft) thick. One large room extends the entire length of the building that provides access to 40 sub-grade processing cells containing tanks, piping and other components. The work breakdown was divided into three major deliverables: (1) Tank D-10 Removal: removal of Tank D-10, which contained TRU waste; (2) Equipment Disposition: placement of contaminated equipment in the sub-grade cells; and (3) Canyon Grouting: grouting canyon void spaces to the maximum extent practical. A large number of pieces of contaminated equipment (pumps, piping, centrifuges, tanks, etc) from other facilities that had been stored on the canyon operating floor were placed inside of the sub-grade cells as final disposition, grouted and the cell shield plug reinstalled. This action precluded a large volume of waste being transported to another burial site. Finally, {approx}19,000 m3 ({approx}25,000 yd3) of grout was placed inside of the cells (in and around the contaminated equipment), in the major galleries. the ventilation tunnel, the external ventilation duct, and the hot pipe trench to minimize the potential for void spaces and to reduce the mobility, solubility, and/or toxicity of the grouted waste

Stabilization process of metallic mercury by sulphur

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

Vaudey, Claire-Emilie; Bardy, Maud; Huc, Christelle

2013-07-01

The technical field of this subject can be described as the treatment of mercury based wastes in order to stock or eliminate them. Toxic mercury vapours prevent from directly stocking or incinerating the wastes. Therefore, some processes have already been implemented to reduce the mercury mobility. Those immobilization processes are created to avoid mercury release in the atmosphere by volatilization or in the soil by leaching. Among the 3 current processes: encapsulation, amalgamation and stabilization, we took an interest on the last one. Stabilization can be defined as an immobilization due to a combination between a molecule and motionless particlesmore » to reduce the release of dangerous elements in the atmosphere or the biosphere. The most common technique of metallic mercury stabilization found in readings is the sulphur amalgamation technique. It consists in the chemical reaction: Hg + S → HgS. A mercury sulphide is then produced and is very insoluble in the water. A 386 deg. C heating transforms it in red sulphide. The obtained mixture can be easily and safely stored in a waste storage. In this context, solid sulphur is added in wide excess compared to the liquid mercury to cause the reaction: Hg(l) + S(s) → HgS(s) with a molar ratio between 1/6.5 and 1/19. The main drawback of this technique is the generation of an important waste quantity: a mixture of HgS and sulphur. Moreover there's no guarantee about the absence of mercury vapours. Therefore there's a real need to improve the ratio and the safety of the reaction, which is the purpose of this study. The volume of the created product is greatly reduced in this case and authorizes significant savings on storage costs. The other experimental parameters discussed in this study are temperature, volume, flask type and mixing speed. (authors)« less

The Geopolitics of Nuclear Waste.

ERIC Educational Resources Information Center

Marshall, Eliot

1991-01-01

The controversy surrounding the potential storage of nuclear waste at Yucca Mountain, Nevada, is discussed. Arguments about the stability of the site and the groundwater situation are summarized. The role of the U.S. Department of Energy and other political considerations are described. (CW)

The use of waste ceramic tile in cement production

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

Ay, N.; Uenal, M.

In ceramic tile production, because of various reasons, unsold fired products come out. These are waste tiles and only a little part of them are used. Remainings create environmental problems. If these waste tiles are used in cement production, this pollution decreases. In this study, usage of waste tile as pozzolan was studied. Waste tile was added into Portland cement in 25%, 30%, 35%, and 40% weight ratios. Pozzolanic properties of waste tile and setting time, volume stability, particle size, density, specific surface area, and strength of cement including waste tile were investigated. The test results indicated that the wastemore » tiles show pozzolanic properties, and chemical and physical properties of the cement including tile conforms to cement standard up to the addition of 35% waste tile.« less

TECHNOLOGY EVALUATION REPORT: CHEMFIX TECHNOLOGIES, INC. - SOLIDIFICATION/STABILIZATION PROCESS - CLACKAMAS, OREGON - VOLUME II

EPA Science Inventory

The CHEMFIX solidification/stabilization process was evaluated in the U.S. Environmental Protection Agency's SITE program. Waste from an uncontrolled hazardous waste site was treated by the CHEMFIX process and subjected to a variety of physical and chemical test methods. Physical...

Microbial stabilization and mass reduction of wastes containing radionuclides and toxic metals

DOEpatents

Francis, A.J.; Dodge, C.J.; Gillow, J.B.

1991-09-10

A process is provided to treat wastes containing radionuclides and toxic metals with Clostridium sp. BFGl to release a large fraction of the waste solids into solution and convert the radionuclides and toxic metals to a more concentrated and stable form with concurrent volume and mass reduction. The radionuclides and toxic metals being in a more stable form are available for recovery, recycling and disposal. 18 figures.

Microbial stabilization and mass reduction of wastes containing radionuclides and toxic metals

DOEpatents

Francis, Arokiasamy J.; Dodge, Cleveland J.; Gillow, Jeffrey B.

1991-01-01

A process is provided to treat wastes containing radionuclides and toxic metals with Clostridium sp. BFGl to release a large fraction of the waste solids into solutin and convert the radionuclides and toxic metals to a more concentrated and stable form with concurrent volume and mass reduction. The radionuclides and toxic metals being in a more stable form are available for recovery, recycling and disposal.

75 FR 9590 - Environmental Management Site-Specific Advisory Board, Idaho National Laboratory

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

... current agenda): Progress to Cleanup. InSitu Grouting--Work Plan Follow-up Discussion. Experimental... meeting be announced in the Federal Register. DATES: Tuesday, March 16, 2010, 8 a.m.-5 p.m. Opportunities... in the areas of environmental restoration, waste management, and related activities. Tentative Topics...

Effect of aeration rate and waste load on evolution of volatile fatty acids and waste stabilization during thermophilic aerobic digestion of a model high strength agricultural waste.

PubMed

Ugwuanyi, J Obeta; Harvey, L M; McNeil, B

2005-04-01

Thermophilic aerobic digestion (TAD) is a relatively new, dynamic and versatile low technology for the economic processing of high strength waste slurries. Waste so treated may be safely disposed of or reused. In this work a model high strength agricultural waste, potato peel, was subjected to TAD to study the effects of oxygen supply at 0.1, 0.25, 0.5 and 1.0 vvm (volume air per volume slurry per minute) under batch conditions at 55 degrees C for 156 h on the process. Process pH was controlled at 7.0 or left unregulated. Effects of waste load, as soluble chemical oxygen demand (COD), on TAD were studied at 4.0, 8.0, 12.0 and 16.0 gl(-1) (soluble COD) at pH 7.0, 0.5 vvm and 55 degrees C. Efficiency of treatment, as degradation of total solids, total suspended solids and soluble solid, as well as soluble COD significantly increased with aeration rate, while acetate production increased as the aeration rate decreased or waste load increased, signifying deterioration in treatment. Negligible acetate, and no other acids were produced at 1.0 vvm. Production of propionate and other acids increased after acetate concentration had started to decrease and, during unregulated reactions coincided with the drop in the pH of the slurry. Acetate production was more closely associated with periods of oxygen limitation than were other acids. Reduction in oxygen availability led to deterioration in treatment efficiency as did increase in waste load. These variables may be manipulated to control treated waste quality.

Application of advanced techniques for the assessment of bio-stability of biowaste-derived residues: A minireview.

PubMed

Lü, Fan; Shao, Li-Ming; Zhang, Hua; Fu, Wen-Ding; Feng, Shi-Jin; Zhan, Liang-Tong; Chen, Yun-Min; He, Pin-Jing

2018-01-01

Bio-stability is a key feature for the utilization and final disposal of biowaste-derived residues, such as aerobic compost or vermicompost of food waste, bio-dried waste, anaerobic digestate or landfilled waste. The present paper reviews conventional methods and advanced techniques used for the assessment of bio-stability. The conventional methods are reclassified into two categories. Advanced techniques, including spectroscopic (fluorescent, ultraviolet-visible, infrared, Raman, nuclear magnetic resonance), thermogravimetric and thermochemolysis analysis, are emphasized for their application in bio-stability assessment in recent years. Their principles, pros and cons are critically discussed. These advanced techniques are found to be convenient in sample preparation and to supply diversified information. However, the viability of these techniques as potential indicators for bio-stability assessment ultimately lies in the establishment of the relationship of advanced ones with the conventional methods, especially with the methods based on biotic response. Furthermore, some misuses in data explanation should be noted. Copyright © 2017 Elsevier Ltd. All rights reserved.

A continuous operating protection system called COPS

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

Chaperon, G.

1987-01-01

The continuous operating protection system called COPS is a diverless solution to achieve the stabilization and protection of subsea pipelines and cables: the system is based on the use of a continuous fabric form work mattress which is spread on the sea bed over the pipeline or cable to be protected by a remotely controlled underwater crawler and simultaneously filled with cement grout. The method has been successfully used in the GULLFAKS field where about 3.6 km of grout mattresses having a cross section of 2 meters by 0.2 meters have been laid. The performances of the system are presentedmore » as well as a trade off comparison with the other stabilization and protection methods currently used: burying, rock dumping or placement of covers.« less

Improved oxidative stability of biodiesel via alternative processing methods using cottonseed oil

USDA-ARS?s Scientific Manuscript database

Biodiesel from waste cooking oil (WCO) requires antioxidants to meet oxidation stability specifications set forth in ASTM D6751 or EN 14214. In contrast, unrefined cottonseed oil (CSO), containing tocopherols and gossypol, produces biodiesel of higher oxidation stability. However, only a portion of ...

Method for the capture and storage of waste

DOEpatents

None

2017-01-24

Systems and methods for capturing waste are disclosed. The systems and methods provide for a high level of confinement and long term stability. The systems and methods include adsorbing waste into a metal-organic framework (MOF), and applying pressure to the MOF material's framework to crystallize or make amorphous the MOF material thereby changing the MOF's pore structure and sorption characteristics without collapsing the MOF framework.

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.

10 CFR 61.44 - Stability of the disposal site after closure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Stability of the disposal site after closure. 61.44 Section 61.44 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Performance Objectives § 61.44 Stability of the disposal site after closure. The disposal...

10 CFR 61.44 - Stability of the disposal site after closure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Stability of the disposal site after closure. 61.44 Section 61.44 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Performance Objectives § 61.44 Stability of the disposal site after closure. The disposal...

10 CFR 61.44 - Stability of the disposal site after closure.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Stability of the disposal site after closure. 61.44 Section 61.44 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Performance Objectives § 61.44 Stability of the disposal site after closure. The disposal...

10 CFR 61.44 - Stability of the disposal site after closure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Stability of the disposal site after closure. 61.44 Section 61.44 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Performance Objectives § 61.44 Stability of the disposal site after closure. The disposal...

10 CFR 61.44 - Stability of the disposal site after closure.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Stability of the disposal site after closure. 61.44 Section 61.44 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Performance Objectives § 61.44 Stability of the disposal site after closure. The disposal...

TECHNOLOGY EVALUATION REPORT: CHEMFIX TECHNOLOGIES, INC. - SOLIDIFICATION/STABILIZATION PROCESS - CLACKAMAS, OREGON - VOLUME I

EPA Science Inventory

The CHEMFIX solidification/stabilization process was evaluated in the U.S. Environment Protection Agency's SITE program. Waste from an uncontrolled hazardous waste site was treated by the CHEMFIX process and subjected to a variety of physical and chemical test methods. Physical t...

Shear Performance of Horizontal Joints in Short Precast Concrete Columns with Sleeve Grouted Connections under Cyclic Loading

PubMed Central

Liu, Bingyu; Chen, Jiang; Zhang, Yiping

2016-01-01

In this study, two short precast concrete columns and two cast-in-situ concrete columns were tested under cyclic loads. It was shown that the sleeve grouted connection was equivalent to the cast-in-situ connections for short columns when the axial compression ratio was 0.6. In order to determine the influence of the axial compression ratio and the shear-span ratio on the shear capacity of the horizontal joint, a FE model was established and verified. The analysis showed that the axial compression ratio is advantageous to the joint and the shear capacity of the horizontal joint increases with increase of the shear-span ratio. Based on the results, the methods used to estimate the shear capacity of horizontal joints in the Chinese Specification and the Japanese Guidelines are discussed and it was found that both overestimated the shear capacity of the horizontal joint. In addition, the Chinese Specification failed to consider the influence of the shear-span ratio. PMID:27861493

Commercial Submersible Mixing Pump For SRS Tank Waste Removal - 15223

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

Hubbard, Mike; Herbert, James E.; Scheele, Patrick W.

The Savannah River Site Tank Farms have 45 active underground waste tanks used to store and process nuclear waste materials. There are 4 different tank types, ranging in capacity from 2839 m 3 to 4921 m 3 (750,000 to 1,300,000 gallons). Eighteen of the tanks are older style and do not meet all current federal standards for secondary containment. The older style tanks are the initial focus of waste removal efforts for tank closure and are referred to as closure tanks. Of the original 51 underground waste tanks, six of the original 24 older style tanks have completed waste removalmore » and are filled with grout. The insoluble waste fraction that resides within most waste tanks at SRS requires vigorous agitation to suspend the solids within the waste liquid in order to transfer this material for eventual processing into glass filled canisters at the Defense Waste Processing Facility (DWPF). SRS suspends the solid waste by use of recirculating mixing pumps. Older style tanks generally have limited riser openings which will not support larger mixing pumps, since the riser access is typically 58.4 cm (23 inches) in diameter. Agitation for these tanks has been provided by four long shafted standard slurry pumps (SLP) powered by an above tank 112KW (150 HP) electric motor. The pump shaft is lubricated and cooled in a pressurized water column that is sealed from the surrounding waste in the tank. Closure of four waste tanks has been accomplished utilizing long shafted pump technology combined with heel removal using multiple technologies. Newer style waste tanks at SRS have larger riser openings, allowing the processing of waste solids to be accomplished with four large diameter SLPs equipped with 224KW (300 HP) motors. These tanks are used to process the waste from closure tanks for DWPF. In addition to the SLPs, a 224KW (300 HP) submersible mixer pump (SMP) has also been developed and deployed within older style tanks. The SMPs are product cooled and product lubricated

Reuse of municipal solid wastes incineration fly ashes in concrete mixtures.

PubMed

Collivignarelli, Carlo; Sorlini, Sabrina

2002-01-01

This study is aimed at assessing the feasibility of concrete production using stabilized m.s.w. (municipal solid waste) incineration fly ashes in addition to natural aggregates. The tested fly ashes were washed and milled, then stabilized by a cement-lime process and finally were reused as a "recycled aggregate" for cement mixture production, in substitution of a natural aggregate (with dosage of 200-400 kg m(-3)). These mixtures, after curing, were characterized with conventional physical-mechanical tests (compression, traction, flexure, modulus of elasticity, shrinkage). In samples containing 200 kg(waste) m(-3)(concrete), a good compressive strength was achieved after 28 days of curing. Furthermore, concrete leaching behavior was evaluated by means of different leaching tests, both on milled and on monolithic samples. Experimental results showed a remarkable reduction of metal leaching in comparison with raw waste. In some cases, similar behavior was observed in "natural" concrete (produced with natural aggregates) and in "waste containing" concrete.

Potential migration of buoyant LNAPL from intermediate level waste (ILW) emplaced in a geological disposal facility (GDF) for U.K. radioactive waste.

PubMed

Benbow, Steven J; Rivett, Michael O; Chittenden, Neil; Herbert, Alan W; Watson, Sarah; Williams, Steve J; Norris, Simon

2014-10-15

A safety case for the disposal of Intermediate Level (radioactive) Waste (ILW) in a deep geological disposal facility (GDF) requires consideration of the potential for waste-derived light non-aqueous phase liquid (LNAPL) to migrate under positive buoyancy from disposed waste packages. Were entrainment of waste-derived radionuclides in LNAPL to occur, such migration could result in a shorter overall travel time to environmental or human receptors than radionuclide migration solely associated with the movement of groundwater. This paper provides a contribution to the assessment of this issue through multiphase-flow numerical modelling underpinned by a review of the UK's ILW inventory and literature to define the nature of the associated ILW LNAPL source term. Examination has been at the waste package-local GDF environment scale to determine whether proposed disposal of ILW would lead to significant likelihood of LNAPL migration, both from waste packages and from a GDF vault into the local host rock. Our review and numerical modelling support the proposition that the release of a discrete free phase LNAPL from ILW would not present a significant challenge to the safety case even with conservative approximations. 'As-disposed' LNAPL emplaced with the waste is not expected to pose a significant issue. 'Secondary LNAPL' generated in situ within the disposed ILW, arising from the decomposition of plastics, in particular PVC (polyvinyl chloride), could form the predominant LNAPL source term. Released high molecular weight phthalate plasticizers are judged to be the primary LNAPL potentially generated. These are expected to have low buoyancy-based mobility due to their very low density contrast with water and high viscosity. Due to the inherent uncertainties, significant conservatisms were adopted within the numerical modelling approach, including: the simulation of a deliberately high organic material--PVC content wastestream (2D03) within an annular grouted waste package

Compaction of Space Mission Wastes

NASA Technical Reports Server (NTRS)

Fisher, John; Pisharody, Suresh; Wignarajah, K.

2004-01-01

The current solid waste management system employed on the International Space Station (ISS) consists of compaction, storage, and disposal. Wastes such plastic food packaging and trash are compacted manually and wrapped in duct tape footballs by the astronauts. Much of the waste is simply loaded either into the empty Russian Progress vehicle for destruction on reentry or into Shuttle for return to Earth. This manual method is wasteful of crew time and does not transition well to far term missions. Different wastes onboard spacecraft vary considerably in their characteristics and in the appropriate method of management. In advanced life support systems for far term missions, recovery of resources such as water from the wastes becomes important. However waste such as plastic food packaging, which constitutes a large fraction of solid waste (roughly 21% on ISS, more on long duration missions), contains minimal recoverable resource. The appropriate management of plastic waste is waste stabilization and volume minimization rather than resource recovery. This paper describes work that has begun at Ames Research Center on development of a heat melt compactor that can be used on near term and future missions, that can minimize crew interaction, and that can handle wastes with a significant plastic composition. The heat melt compactor takes advantage of the low melting point of plastics to compact plastic materials using a combination of heat and pressure. The US Navy has demonstrated successful development of a similar unit for shipboard application. Ames is building upon the basic approach demonstrated by the Navy to develop an advanced heat melt type compactor for space mission type wastes.

75 FR 346 - Environmental Management Site-Specific Advisory Board, Idaho National Laboratory

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-05

... current agenda): Progress to Cleanup. InSitu Grouting--Draft Remedial Design and Remedial Action Work Plan... this meeting be announced in the Federal Register. DATES: Wednesday, January 20, 2010, 8 a.m.-5 p.m... in the areas of environmental restoration, waste management, and related activities. Tentative Topics...

SIMPLE TRANSIENT CALCULATIONS OF CELL FLAMMABLE GAS CONCENTRATIONS

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

NOEMAIL), J; David Allison; John Mccord, J

2009-05-06

The Saltstone Facility at Savannah River Site (SRS) mixes low-level radiological liquid waste with grout for permanent disposal as cement in vault cells. The grout mixture is poured into each cell in approximately 17 batches (8 to 10 hours duration). The grout mixture contains ten flammable gases of concern that are released from the mixture into the cell. Prior to operations, simple parametric transient calculations were performed to develop batch parameters (including schedule of batch pours) to support operational efficiency while ensuring that a flammable gas mixture does not develop in the cell vapor space. The analysis demonstrated that amore » nonflammable vapor space environment can be achieved, with workable operational constraints, without crediting the ventilation flow as a safety system control. Isopar L was identified as the primary flammable gas of concern. The transient calculations balanced inflows of the flammable gases into the vapor space with credited outflows of diurnal breathing through vent holes and displacement from new grout pours and gases generated. Other important features of the analyses included identifying conditions that inhibited a well-mixed vapor space, the expected frequency and duration of such conditions, and the estimated level of stratification that could develop.« less

Estimating Residual Solids Volume In Underground Storage Tanks

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

Clark, Jason L.; Worthy, S. Jason; Martin, Bruce A.

2014-01-08

The Savannah River Site liquid waste system consists of multiple facilities to safely receive and store legacy radioactive waste, treat, and permanently dispose waste. The large underground storage tanks and associated equipment, known as the 'tank farms', include a complex interconnected transfer system which includes underground transfer pipelines and ancillary equipment to direct the flow of waste. The waste in the tanks is present in three forms: supernatant, sludge, and salt. The supernatant is a multi-component aqueous mixture, while sludge is a gel-like substance which consists of insoluble solids and entrapped supernatant. The waste from these tanks is retrieved andmore » treated as sludge or salt. The high level (radioactive) fraction of the waste is vitrified into a glass waste form, while the low-level waste is immobilized in a cementitious grout waste form called saltstone. Once the waste is retrieved and processed, the tanks are closed via removing the bulk of the waste, chemical cleaning, heel removal, stabilizing remaining residuals with tailored grout formulations and severing/sealing external penetrations. The comprehensive liquid waste disposition system, currently managed by Savannah River Remediation, consists of 1) safe storage and retrieval of the waste as it is prepared for permanent disposition; (2) definition of the waste processing techniques utilized to separate the high-level waste fraction/low-level waste fraction; (3) disposition of LLW in saltstone; (4) disposition of the HLW in glass; and (5) closure state of the facilities, including tanks. This paper focuses on determining the effectiveness of waste removal campaigns through monitoring the volume of residual solids in the waste tanks. Volume estimates of the residual solids are performed by creating a map of the residual solids on the waste tank bottom using video and still digital images. The map is then used to calculate the volume of solids remaining in the waste tank. The

Biodegradation and flushing of MBT wastes

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

Siddiqui, A.A., E-mail: aasiddiqui.cv@amu.ac.in; Richards, D.J.; Powrie, W.

Highlights: • Stabilization was achieved for MBT wastes of different degrees of pretreatment. • About 92% reduction in the gas generation compared with raw MSW. • Pretreatment resulted in reduced TOC, nitrogen and heavy metals in leachate. • A large proportion of carbon and nitrogen remained in the waste material. - Abstract: Mechanical–biological treatment (MBT) processes are increasingly being adopted as a means of diverting biodegradable municipal waste (BMW) from landfill, for example to comply with the EU Landfill Directive. However, there is considerable uncertainty concerning the residual pollution potential of such wastes. This paper presents the results of laboratorymore » experiments on two different MBT waste residues, carried out to investigate the remaining potential for the generation of greenhouse gases and the flushing of contaminants from these materials when landfilled. The potential for gas generation was found to be between 8% and 20% of that for raw MSW. Pretreatment of the waste reduced the potential for the release of organic carbon, ammoniacal nitrogen, and heavy metal contents into the leachate; and reduced the residual carbon remaining in the waste after final degradation from ∼320 g/kg dry matter for raw MSW to between 183 and 195 g/kg dry matter for the MBT wastes.« less

Investigation of the leaching behavior of lead in stabilized/solidified waste using a two-year semi-dynamic leaching test.

PubMed

Xue, Qiang; Wang, Ping; Li, Jiang-Shan; Zhang, Ting-Ting; Wang, Shan-Yong

2017-01-01

Long-term leaching behavior of contaminant from stabilization/solidification (S/S) treated waste stays unclear. For the purpose of studying long-term leaching behavior and leaching mechanism of lead from cement stabilized soil under different pH environment, semi-dynamic leaching test was extended to two years to investigate leaching behaviors of S/S treated lead contaminated soil. Effectiveness of S/S treatment in different scenarios was evaluated by leachability index (LX) and effective diffusion coefficient (D e ). In addition, the long-term leaching mechanism was investigated at different leaching periods. Results showed that no significant difference was observed among the values of the cumulative release of Pb, D e and LX in weakly alkaline and weakly acidic environment (pH value varied from 5.00 to 10.00), and all the controlling leaching mechanisms of the samples immersed in weakly alkaline and weakly acidic environments turned out to be diffusion. Strong acid environment would significantly affect the leaching behavior and leaching mechanism of lead from S/S monolith. The two-year variation of D e appeared to be time dependent, and D e values increased after the 210 th day in weakly alkaline and weakly acidic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, task 17208: Final report

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

Amoroso, J. W.; Marra, J. C.

2015-08-26

A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics)more » over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).« less

Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, Task 17208: Final report

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

Amoroso, J. W.; Marra, J. C.

2015-08-26

A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics)more » over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).« less

LEACHING BOUNDARY IN CEMENT-BASED WASTE FORMS

EPA Science Inventory

Cement-based fixation systems are among the most commonly employed stabilization/solidification techniques. These cement haste mixtures, however, are vulnerable to ardic leaching solutions. Leaching of cement-based waste forms in acetic acid solutions with different acidic streng...

Modeling Nitrogen Dynamics in a Waste Stabilization Pond System Using Flexible Modeling Environment with MCMC.

PubMed

Mukhtar, Hussnain; Lin, Yu-Pin; Shipin, Oleg V; Petway, Joy R

2017-07-12

This study presents an approach for obtaining realization sets of parameters for nitrogen removal in a pilot-scale waste stabilization pond (WSP) system. The proposed approach was designed for optimal parameterization, local sensitivity analysis, and global uncertainty analysis of a dynamic simulation model for the WSP by using the R software package Flexible Modeling Environment (R-FME) with the Markov chain Monte Carlo (MCMC) method. Additionally, generalized likelihood uncertainty estimation (GLUE) was integrated into the FME to evaluate the major parameters that affect the simulation outputs in the study WSP. Comprehensive modeling analysis was used to simulate and assess nine parameters and concentrations of ON-N, NH₃-N and NO₃-N. Results indicate that the integrated FME-GLUE-based model, with good Nash-Sutcliffe coefficients (0.53-0.69) and correlation coefficients (0.76-0.83), successfully simulates the concentrations of ON-N, NH₃-N and NO₃-N. Moreover, the Arrhenius constant was the only parameter sensitive to model performances of ON-N and NH₃-N simulations. However, Nitrosomonas growth rate, the denitrification constant, and the maximum growth rate at 20 °C were sensitive to ON-N and NO₃-N simulation, which was measured using global sensitivity.

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.

Geotechnical engineering for ocean waste disposal. An introduction

USGS Publications Warehouse

Lee, Homa J.; Demars, Kenneth R.; Chaney, Ronald C.; ,

1990-01-01

As members of multidisciplinary teams, geotechnical engineers apply quantitative knowledge about the behavior of earth materials toward designing systems for disposing of wastes in the oceans and monitoring waste disposal sites. In dredge material disposal, geotechnical engineers assist in selecting disposal equipment, predict stable characteristics of dredge mounds, design mound caps, and predict erodibility of the material. In canister disposal, geotechnical engineers assist in specifying canister configurations, predict penetration depths into the seafloor, and predict and monitor canister performance following emplacement. With sewage outfalls, geotechnical engineers design foundation and anchor elements, estimate scour potential around the outfalls, and determine the stability of deposits made up of discharged material. With landfills, geotechnical engineers evaluate the stability and erodibility of margins and estimate settlement and cracking of the landfill mass. Geotechnical engineers also consider the influence that pollutants have on the engineering behavior of marine sediment and the extent to which changes in behavior affect the performance of structures founded on the sediment. In each of these roles, careful application of geotechnical engineering principles can contribute toward more efficient and environmentally safe waste disposal operations.

Mercury contamination - Amalgamate (contract with NFS and ADA). Stabilize Elemental Mercury Wastes. Mixed Waste Focus Area. OST Reference Number 1675

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

None, None

1999-09-01

Through efforts led by the Mixed Waste Focus Area (MWFA) and its Mercury Working Group (HgWG), the inventory of bulk elemental mercury contaminated with radionuclides stored at various U. S. Department of Energy (DOE) sites is thought to be approximately 16 m3 (Conley et al. 1998). At least 19 different DOE sites have this type of mixed low-level waste in their storage facilities. The U. S. Environmental Protection Agency (EPA) specifies amalgamation as the treatment method for radioactively contaminated elemental mercury. Although the chemistry of amalgamation is well known, the practical engineering of a sizable amalgamation process has not beenmore » tested (Tyson 1993). To eliminate the existing DOE inventory in a reasonable timeframe, scaleable equipment is needed that can: produce waste forms that meet the EPA definition of amalgamation, produce waste forms that pass the EPA Toxicity Characteristic Leaching Procedure (TCLP) limit of 0.20 mg/L, limit mercury vapor concentrations during processing to below the Occupational Safety and Health Administration’s (OSHA) 8-hour worker exposure limit (50 mg/m3) for mercury, and perform the above economically.« less

Co-digestion of pig slaughterhouse waste with sewage sludge.

PubMed

Borowski, Sebastian; Kubacki, Przemysław

2015-06-01

Slaughterhouse wastes (SHW) are potentially very attractive substrates for biogas production. However, mono-digestion of these wastes creates great technological problems associated with the inhibitory effects of ammonia and fatty acids on methanogens as well as with the foaming in the digesters. In the following study, the co-digestion of slaughterhouse wastes with sewage sludge (SS) was undertaken. Batch and semi-continuous experiments were performed at 35°C with municipal sewage sludge and pig SHW composed of meat tissue, intestines, bristles and post-flotation sludge. In batch assays, meat tissue and intestinal wastes gave the highest methane productions of 976 and 826 dm(3)/kg VS, respectively, whereas the methane yield from the sludge was only 370 dm(3)/kg VS. The co-digestion of sewage sludge with 50% SHW (weight basis) provided the methane yield exceeding 600 dm(3)/kg VS, which was more than twice as high as the methane production from sewage sludge alone. However, when the loading rate exceeded 4 kg VS/m(3) d, a slight inhibition of methanogenesis was observed, without affecting the digester stability. The experiments showed that the co-digestion of sewage sludge with large amount of slaughterhouse wastes is feasible, and the enhanced methane production does not affect the digester stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

APPLICATIONS ANALYSIS REPORT: CHEMFIX TECHNOLOGIES, INC. - SOLIDIFICATION/STABILIZATION PROCESS

EPA Science Inventory

In support of the U.S. Environmental Protection Agency's (EPA) Superfund Innovative Technology Evaluation (SITE) Program, this report evaluates the Chemfix Technologies, Inc. (Chemfix), solidification/stabilization technology for on-site treatment of hazardous waste. The Chemfix ...

Siting industrial waste land disposal facilities in Thailand: A risk based approach

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

Fingleton, D.J.; Habegger, L.; Peters, R.

The Thailand Industrial Works Department (IWD) has established a toxic industrial waste Central Treatment and Stabilization Center (CTSC) for textile dyeing and electroplating industries located in the Thonburi region of the Bangkok metropolitan area. Industrial waste is treated, stabilized, and stored at the CTSC. Although the IWD plans to ship the stabilized sludge to the Ratchaburi Province in western Thailand for burial, the location for the land disposal site has not been selected. Assessing the relative health risks from exposure to toxic chemicals released from an industrial waste land disposal site is a complicated, data-intensive process that requires a multidisciplinarymore » approach. This process is further complicated by the unique physical and cultural characteristics exhibited by the rapidly industrializing Thai economy. The purpose of this paper is to describe the research approach taken and to detail the constraints to health risk assessments in Thailand. issues discussed include data availability and quality, effectiveness of control or mitigation methods, cultural differences, and the basic assumptions inherent in many of the risk assessment components.« less

Biostabilization of landfill waste

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

Hansen, D.L.

1995-06-01

In November 1991, the city of Albany, N.Y., together with the principals of Landfill Service Corp. (Apalachin, N.Y.), proposed to demonstrate the successful practice of biostabilized solid waste placement in the newly constructed, double-composite-lined Interim Landfill located in the city of Albany. The small landfill covers just 12 acres and is immediately adjacent to residential neighbors. The benefits of this biostabilization practice include a dramatic improvement in the orderliness of waste placement, with significant reduction of windblown dust and litter. The process also reduces the presence of typical landfill vectors such as flies, crows, seagulls, and rodents. The physically andmore » biologically uniform character of the stabilized waste mass can result in more uniform future landfill settlement and gas production properties. This can allow for more accurate prediction of post-closure conditions and reduction or elimination of remedial costs attendant to post-closure gross differential settlement.« less

TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

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

James T. Cobb, Jr.

2003-09-12

Metal-laden wastes can be stabilized and solidified using advanced clean coal technology by-products (CCTBs)--fluid bed combustor ash and spray drier solids. These utility-generated treatment chemicals are available for purchase through brokers, and commercial applications of this process are being practiced by treaters of metal-laden hazardous waste. A complex of regulations governs this industry, and sensitivities to this complex has discouraged public documentation of treatment of metal-laden hazardous wastes with CCTBs. This report provides a comprehensive public documentation of laboratory studies that show the efficacy of the stabilization and solidification of metal-laden hazardous wastes--such as lead-contaminated soils and sandblast residues--through treatmentmore » with CCTBs. It then describes the extensive efforts that were made to obtain the permits allowing a commercial hazardous waste treater to utilize CCTBs as treatment chemicals and to install the equipment required to do so. It concludes with the effect of this lengthy process on the ability of the treatment company to realize the practical, physical outcome of this effort, leading to premature termination of the project.« less

Energy recovery from solid waste. Volume 1: Summary report

NASA Technical Reports Server (NTRS)

1975-01-01

A systems analysis of energy recovery from solid waste which demonstrates the feasibility of several processes for converting solid waste to an energy form is presented. The social, legal, environmental, and political factors are considered and recommendations made in regard to legislation and policy. A technical and economic evaluation of available and developing energy-recovery processes is given with emphasis on thermal decomposition and biodegradation. A pyrolysis process is suggested. The use of prepared solid waste as a fuel supplemental to coal is considered to be the most economic process for recovery of energy from solid waste. Markets are discussed with suggestions for improving market conditions and for developing market stability. A decision procedure is given to aid a community in deciding on its options in dealing with solid waste.

Results Of Insulation Resistance Between Solar Cell String Gaps Without RTV Adhesive Grout After Electrostatic Discharge Tests With Cover Glass Flashover

NASA Astrophysics Data System (ADS)

Hoang, Bao; Wong, Frankie; Redick, Tod; Masui, Hirokazu; Endo, Taishi; Toyoda, Kazuhiro; Cho, Mengu

2011-10-01

A series of electrostatic discharge (ESD) tests was performed on solar array test coupons consisting of Advanced Triple Junction InGaP2/InGaAs/Ge solar cells. The motivation for these tests was to evaluate the effects of ESD on solar array design without room temperature vulcanized (RTV) adhesive grout between the string-to-string parallel gaps. To investigate the threshold of permanently sustained secondary arcs, various combinations of gap width, load voltage and string current were tested in a vacuum chamber equipped with an electron beam gun. This ESD test program included the ESD test circuit with simulated panel coverglass flashover. Although ESD events did not result in permanent sustained arcs, the insulation resistance between strings was found to decrease as the number of secondary arcs accumulated in the gap.

Testing and Analysis of the First Plastic Melt Waste Compactor Prototype

NASA Technical Reports Server (NTRS)

Pace, Gregory S.; Fisher, John W.

2005-01-01

A half scale Plastic Melt Waste Compactor prototype has been developed at NASA Ames Research Center. The half scale prototype unit will lead to the development of a full scale Plastic Melt Waste Compactor prototype that is representative of flight hardware that would be used on near and far term space missions. This report details the testing being done on the prototype Plastic Melt Waste Compactor by the Solid Waste Management group at NASA Ames Research Center. The tests are designed to determine the prototype's functionality, simplicity of operation, ability to contain and control noxious off-gassing, biological stability of the processed waste, and water recovery potential using a waste composite that is representative of the types of wastes produced on the International Space Station, Space Shuttle, MIR and Skylab missions.

Secondary Waste Form Down Selection Data Package – Ceramicrete

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

Cantrell, Kirk J.; Westsik, Joseph H.

2011-08-31

As part of high-level waste pretreatment and immobilized low activity waste processing, liquid secondary wastes will be generated that will be transferred to the Effluent Treatment Facility on the Hanford Site for further treatment. These liquid secondary wastes will be converted to stable solid waste forms that will be disposed in the Integrated Disposal Facility. Currently, four waste forms are being considered for stabilization and solidification of the liquid secondary wastes. These waste forms are Cast Stone, Ceramicrete, DuraLith, and Fluidized Bed Steam Reformer. The preferred alternative will be down selected from these four waste forms. Pacific Northwest National Laboratorymore » is developing data packages to support the down selection process. The objective of the data packages is to identify, evaluate, and summarize the existing information on the four waste forms being considered for stabilization and solidification of the liquid secondary wastes. The information included will be based on information available in the open literature and from data obtained from testing currently underway. This data package is for the Ceramicrete waste form. Ceramicrete is a relatively new engineering material developed at Argonne National Laboratory to treat radioactive and hazardous waste streams (e.g., Wagh 2004; Wagh et al. 1999a, 2003; Singh et al. 2000). This cement-like waste form can be used to treat solids, liquids, and sludges by chemical immobilization, microencapsulation, and/or macroencapsulation. The Ceramicrete technology is based on chemical reaction between phosphate anions and metal cations to form a strong, dense, durable, low porosity matrix that immobilizes hazardous and radioactive contaminants as insoluble phosphates and microencapsulates insoluble radioactive components and other constituents that do not form phosphates. Ceramicrete is a type of phosphate-bonded ceramic, which are also known as chemically bonded phosphate ceramics. The

Method and article for primary containment of cesium wastes. [DOE patent application

DOEpatents

Angelini, P.; Lackey, W.J.; Stinton, D.P.; Blanco, R.E.; Bond, W.D.; Arnold, W.D. Jr.

1981-09-03

A method for producing a cesium-retentive waste form, characterized by a high degree of compositional stability and mechanical integrity, is provided by subjecting a cesium-loaded zeolite to heat under conditions suitable for stabilizing the zeolite and immobilizing the cesium, and coating said zeolite for sufficient duration within a suitable environment with at least one dense layer of pyrolytic carbon to seal therein said cesium to produce a final, cesium-bearing waste form. Typically, the zolite is stabilized and the cesium immobilized in less than four hours by confinement within an air environment maintained at about 600/sup 0/C. Coatings are thereafter applied by confining the calcined zeolite within a coating environment comprising inert fluidizing and carbon donor gases maintained at 1000/sup 0/C for a suitable duration.