Apparatus for the processing of solid mixed waste containing radioactive and hazardous materials

DOEpatents

Gotovchikov, Vitaly T.; Ivanov, Alexander V.; Filippov, Eugene A.

1999-03-16

Apparatus for the continuous heating and melting of a solid mixed waste bearing radioactive and hazardous materials to form separate metallic, slag and gaseous phases for producing compact forms of the waste material to facilitate disposal includes a copper split water-cooled (cold) crucible as a reaction vessel for receiving the waste material. The waste material is heated by means of the combination oaf plasma torch directed into the open upper portion of the cold crucible and an electromagnetic flux produced by induction coils disposed about the crucible which is transparent to electromagnetic fields. A metallic phase of the waste material is formed in a lower portion of the crucible and is removed in the form of a compact ingot suitable for recycling and further processing. A glass-like, non-metallic slag phase containing radioactive elements is also formed in the crucible and flows out of the open upper portion of the crucible into a slag ingot mold for disposal. The decomposition products of the organic and toxic materials are incinerated and converted to environmentally safe gases in the melter.

Processing of solid mixed waste containing radioactive and hazardous materials

DOEpatents

Gotovchikov, Vitaly T.; Ivanov, Alexander V.; Filippov, Eugene A.

1998-05-12

Apparatus for the continuous heating and melting of a solid mixed waste bearing radioactive and hazardous materials to form separate metallic, slag and gaseous phases for producing compact forms of the waste material to facilitate disposal includes a copper split water-cooled (cold) crucible as a reaction vessel for receiving the waste material. The waste material is heated by means of the combination of a plasma torch directed into the open upper portion of the cold crucible and an electromagnetic flux produced by induction coils disposed about the crucible which is transparent to electromagnetic fields. A metallic phase of the waste material is formed in a lower portion of the crucible and is removed in the form of a compact ingot suitable for recycling and further processing. A glass-like, non-metallic slag phase containing radioactive elements is also formed in the crucible and flows out of the open upper portion of the crucible into a slag ingot mold for disposal. The decomposition products of the organic and toxic materials are incinerated and converted to environmentally safe gases in the melter.

Apparatus for the processing of solid mixed waste containing radioactive and hazardous materials

DOEpatents

Gotovchikov, V.T.; Ivanov, A.V.; Filippov, E.A.

1999-03-16

Apparatus for the continuous heating and melting of a solid mixed waste bearing radioactive and hazardous materials to form separate metallic, slag and gaseous phases for producing compact forms of the waste material to facilitate disposal includes a copper split water-cooled (cold) crucible as a reaction vessel for receiving the waste material. The waste material is heated by means of the combination of a plasma torch directed into the open upper portion of the cold crucible and an electromagnetic flux produced by induction coils disposed about the crucible which is transparent to electromagnetic fields. A metallic phase of the waste material is formed in a lower portion of the crucible and is removed in the form of a compact ingot suitable for recycling and further processing. A glass-like, non-metallic slag phase containing radioactive elements is also formed in the crucible and flows out of the open upper portion of the crucible into a slag ingot mold for disposal. The decomposition products of the organic and toxic materials are incinerated and converted to environmentally safe gases in the melter. 6 figs.

Processing of solid mixed waste containing radioactive and hazardous materials

DOEpatents

Gotovchikov, V.T.; Ivanov, A.V.; Filippov, E.A.

1998-05-12

Apparatus for the continuous heating and melting of a solid mixed waste bearing radioactive and hazardous materials to form separate metallic, slag and gaseous phases for producing compact forms of the waste material to facilitate disposal includes a copper split water-cooled (cold) crucible as a reaction vessel for receiving the waste material. The waste material is heated by means of the combination of a plasma torch directed into the open upper portion of the cold crucible and an electromagnetic flux produced by induction coils disposed about the crucible which is transparent to electromagnetic fields. A metallic phase of the waste material is formed in a lower portion of the crucible and is removed in the form of a compact ingot suitable for recycling and further processing. A glass-like, non-metallic slag phase containing radioactive elements is also formed in the crucible and flows out of the open upper portion of the crucible into a slag ingot mold for disposal. The decomposition products of the organic and toxic materials are incinerated and converted to environmentally safe gases in the melter. 6 figs.

Controlling mechanisms of metals release form cement-based waste form in acetic acid solution

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

Cheng, Kuang Ye.

1991-01-01

The purpose of this dissertation is to identify the individual leaching mechanisms of metals by knowing the pH profile within the leached specimen and the physical and chemical properties of the leached material. Leaching of cement-based waste form in acetic acid solutions with different acidic strengths has been investigated in this work. The pH profile along the acid penetration route in the cement-based waste form was identified by various pH color indicators. The pH in the surface altered layer varies from 5.0 to 6.0, which is very close to the pH in the bulk leachate. A reacting zone, where themore » pH abruptly changes from 6 to 12, sharply divides the altered surface layer from the remaining unleached waste form or kernel. Leaching of metals is controlled by the acidity available in the leachant. Dissolution of alkaline materials leaves a silica-rich layer on the surface of the cement-based waste form. This surface layer exhibits different properties than those of the unleached material. The surface layer has a higher water content, is lighter weight, and is soft and friable. Furthermore, the abundant silicate content on the solid surface detains portion of the leached metals, while they are moving through the leached layer into bulk solution. The leaching of metals is a consequence of acid penetration. The distance from the solid/solution interface to the front of the leaching boundary can be regarded as the depth of leaching zone, where the metals dissolve and diffuse out of the waste form. The metal ions diffuse through the leached layer may be retarded on the solid surface by the pH-dependent adsorption reactions. It is found that the leaching process through the leached layer is diffusion-controlled for calcium and cadmium, whereas diffusion and adsorption occur simultaneously in the leached layer for lead and arsenic.« less

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.

Canister arrangement for storing radioactive waste

DOEpatents

Lorenzo, D.K.; Van Cleve, J.E. Jr.

1980-04-23

The subject invention relates to a canister arrangement for jointly storing high level radioactive chemical waste and metallic waste resulting from the reprocessing of nuclear reactor fuel elements. A cylindrical steel canister is provided with an elongated centrally disposed billet of the metallic waste and the chemical waste in vitreous form is disposed in the annulus surrounding the billet.

Canister arrangement for storing radioactive waste

DOEpatents

Lorenzo, Donald K.; Van Cleve, Jr., John E.

1982-01-01

The subject invention relates to a canister arrangement for jointly storing high level radioactive chemical waste and metallic waste resulting from the reprocessing of nuclear reactor fuel elements. A cylindrical steel canister is provided with an elongated centrally disposed billet of the metallic waste and the chemical waste in vitreous form is disposed in the annulus surrounding the billet.

Closed Fuel Cycle Waste Treatment Strategy

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

Vienna, J. D.; Collins, E. D.; Crum, J. V.

This study is aimed at evaluating the existing waste management approaches for nuclear fuel cycle facilities in comparison to the objectives of implementing an advanced fuel cycle in the U.S. under current legal, regulatory, and logistical constructs. The study begins with the Global Nuclear Energy Partnership (GNEP) Integrated Waste Management Strategy (IWMS) (Gombert et al. 2008) as a general strategy and associated Waste Treatment Baseline Study (WTBS) (Gombert et al. 2007). The tenets of the IWMS are equally valid to the current waste management study. However, the flowsheet details have changed significantly from those considered under GNEP. In addition, significantmore » additional waste management technology development has occurred since the GNEP waste management studies were performed. This study updates the information found in the WTBS, summarizes the results of more recent technology development efforts, and describes waste management approaches as they apply to a representative full recycle reprocessing flowsheet. Many of the waste management technologies discussed also apply to other potential flowsheets that involve reprocessing. These applications are occasionally discussed where the data are more readily available. The report summarizes the waste arising from aqueous reprocessing of a typical light-water reactor (LWR) fuel to separate actinides for use in fabricating metal sodium fast reactor (SFR) fuel and from electrochemical reprocessing of the metal SFR fuel to separate actinides for recycle back into the SFR in the form of metal fuel. The primary streams considered and the recommended waste forms include; Tritium in low-water cement in high integrity containers (HICs); Iodine-129: As a reference case, a glass composite material (GCM) formed by the encapsulation of the silver Mordenite (AgZ) getter material in a low-temperature glass is assumed. A number of alternatives with distinct advantages are also considered including a fused silica waste form with encapsulated nano-sized AgI crystals; Carbon-14 immobilized as a CaCO3 in a cement waste form; Krypton-85 stored as a compressed gas; An aqueous reprocessing high-level waste (HLW) raffinate waste immobilized by the vitrification process; An undissolved solids (UDS) fraction from aqueous reprocessing of LWR fuel either included in the borosilicate HLW glass or immobilized in the form of a metal alloy or titanate ceramics; Zirconium-based LWR fuel cladding hulls and stainless steel (SS) fuel assembly hardware super-compacted for disposal or purified for reuse (or disposal as low-level waste, LLW) of Zr by reactive gas separations; Electrochemical process salt HLW incorporated into a glass bonded Sodalite waste form; and Electrochemical process UDS and SS cladding hulls melted into an iron based alloy waste form. Mass and volume estimates for each of the recommended waste forms based on the source terms from a representative flowsheet are reported. In addition to the above listed primary waste streams, a range of secondary process wastes are generated by aqueous reprocessing of LWR fuel, metal SFR fuel fabrication, and electrochemical reprocessing of SFR fuel. These secondary wastes have been summarized and volumes estimated by type and classification. The important waste management data gaps and research needs have been summarized for each primary waste stream and selected waste process.« less

Chemically bonded phosphate ceramics of trivalent oxides of iron and manganese

DOEpatents

Wagh, Arun S.; Jeong, Seung-Young

2002-01-01

A new method for combining elemental iron and other metals to form an inexpensive ceramic to stabilize arsenic, alkaline red mud wastes, swarfs, and other iron or metal-based additives, to create products and waste forms which can be poured or dye cast.

Corrosion mechanisms for metal alloy waste forms: experiment and theory Level 4 Milestone M4FT-14LA0804024 Fuel Cycle Research & Development

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

Liu, Xiang-Yang; Taylor, Christopher D.; Kim, Eunja

2014-07-31

This document meets Level 4 Milestone: Corrosion mechanisms for metal alloy waste forms - experiment and theory. A multiphysics model is introduces that will provide the framework for the quantitative prediction of corrosion rates of metallic waste forms incorporating the fission product Tc. The model requires a knowledge of the properties of not only the metallic waste form, but also the passive oxide films that will be generated on the waste form, and the chemistry of the metal/oxide and oxide/environment interfaces. in collaboration with experimental work, the focus of this work is on obtaining these properties from fundamental atomistic models.more » herein we describe the overall multiphysics model, which is based on MacDonald's point-defect model for passivity. We then present the results of detailed electronic-structure calculations for the determination of the compatibility and properties of Tc when incorporated into intermetallic oxide phases. This work is relevant to the formation of multi-component oxides on metal surfaces that will incorporate Tc, and provide a kinetic barrier to corrosion (i.e. the release of Tc to the environment). Atomistic models that build upon the electronic structure calculations are then described using the modified embedded atom method to simulate metallic dissolution, and Buckingham potentials to perform classical molecular dynamics and statics simulations of the technetium (and, later, iron-technetium) oxide phases. Electrochemical methods were then applied to provide some benchmark information of the corrosion and electrochemical properties of Technetium metal. The results indicate that published information on Tc passivity is not complete and that further investigation is warranted.« less

Production of iron from metallurgical waste

DOEpatents

Hendrickson, David W; Iwasaki, Iwao

2013-09-17

A method of recovering metallic iron from iron-bearing metallurgical waste in steelmaking comprising steps of providing an iron-bearing metallurgical waste containing more than 55% by weight FeO and FeO equivalent and a particle size of at least 80% less than 10 mesh, mixing the iron-bearing metallurgical waste with a carbonaceous material to form a reducible mixture where the carbonaceous material is between 80 and 110% of the stoichiometric amount needed to reduce the iron-bearing waste to metallic iron, and as needed additions to provide a silica content between 0.8 and 8% by weight and a ratio of CaO/SiO.sub.2 between 1.4 and 1.8, forming agglomerates of the reducible mixture over a hearth material layer to protect the hearth, heating the agglomerates to a higher temperature above the melting point of iron to form nodules of metallic iron and slag material from the agglomerates by melting.

Electrochemical Corrosion Studies for Modeling Metallic Waste Form Release Rates

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

Poineau, Frederic; Tamalis, Dimitri

The isotope 99Tc is an important fission product generated from nuclear power production. Because of its long half-life (t 1/2 = 2.13 ∙ 10 5 years) and beta-radiotoxicity (β⁻ = 292 keV), it is a major concern in the long-term management of spent nuclear fuel. In the spent nuclear fuel, Tc is present as an alloy with Mo, Ru, Rh, and Pd called the epsilon-phase, the relative amount of which increases with fuel burn-up. In some separation schemes for spent nuclear fuel, Tc would be separated from the spent fuel and disposed of in a durable waste form. Technetium wastemore » forms under consideration include metallic alloys, oxide ceramics and borosilicate glass. In the development of a metallic waste form, after separation from the spent fuel, Tc would be converted to the metal, incorporated into an alloy and the resulting waste form stored in a repository. Metallic alloys under consideration include Tc–Zr alloys, Tc–stainless steel alloys and Tc–Inconel alloys (Inconel is an alloy of Ni, Cr and iron which is resistant to corrosion). To predict the long-term behavior of the metallic Tc waste form, understanding the corrosion properties of Tc metal and Tc alloys in various chemical environments is needed, but efforts to model the behavior of Tc metallic alloys are limited. One parameter that should also be considered in predicting the long-term behavior of the Tc waste form is the ingrowth of stable Ru that occurs from the radioactive decay of 99Tc ( 99Tc → 99Ru + β⁻). After a geological period of time, significant amounts of Ru will be present in the Tc and may affect its corrosion properties. Studying the effect of Ru on the corrosion behavior of Tc is also of importance. In this context, we studied the electrochemical behavior of Tc metal, Tc-Ni alloys (to model Tc-Inconel alloy) and Tc-Ru alloys in acidic media. The study of Tc-U alloys has also been performed in order to better understand the nature of Tc in metallic spent fuel. Computational modeling and simulations were performed to shed light on experimental results and explain structural and kinetics trends.« less

[Limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou].

PubMed

Lin, Wen-Jie; Xiao, Tang-Fu; Ao, Zi-Qiang; Xing, Jun; Ma, Huan-Cheng; Hu, Ting-Xing

2007-03-01

With indigenous zinc smelting waste residue, contaminated soil and background soil as test substrates, a pot experiment was conducted to study the growth characteristics of Lolium perenne and Trifolium pretense on these substrates. The results showed that the major limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou were the salt-alkali stress and the lower contents of organic matter, total N, available N and total K. The heavy metals in waste residue had a high concentration, but their available forms only occupied a small proportion, with low toxicity to plant but having potential harmful risk. Contaminated soil had lower concentrations of heavy metals than waste residue, but its contained heavy metals were more in available form. The constraints of revegetation on contaminated soil were the toxicity of heavy metals and the low contents of available P and K. Mixing contaminated soil with zinc smelting waste residue could be one of the effective approaches for the substrate amendment in indigenous zinc smelting areas.

Performance of a Steel/Oxide Composite Waste Form for Combined Waste Steams from Advanced Electrochemical Processes

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

Indacochea, J. E.; Gattu, V. K.; Chen, X.

The results of electrochemical corrosion tests and modeling activities performed collaboratively by researchers at the University of Illinois at Chicago and Argonne National Laboratory as part of workpackage NU-13-IL-UIC-0203-02 are summarized herein. The overall objective of the project was to develop and demonstrate testing and modeling approaches that could be used to evaluate the use of composite alloy/ceramic materials as high-level durable waste forms. Several prototypical composite waste form materials were made from stainless steels representing fuel cladding, reagent metals representing metallic fuel waste streams, and reagent oxides representing oxide fuel waste streams to study the microstructures and corrosion behaviorsmore » of the oxide and alloy phases. Microelectrodes fabricated from small specimens of the composite materials were used in a series of electrochemical tests to assess the corrosion behaviors of the constituent phases and phase boundaries in an aggressive acid brine solution at various imposed surface potentials. The microstructures were characterized in detail before and after the electrochemical tests to relate the electrochemical responses to changes in both the electrode surface and the solution composition. The results of microscopic, electrochemical, and solution analyses were used to develop equivalent circuit and physical models representing the measured corrosion behaviors of the different materials pertinent to long-term corrosion behavior. This report provides details regarding (1) the production of the composite materials, (2) the protocol for the electrochemical measurements and interpretations of the responses of multi-phase alloy and oxide composites, (3) relating corrosion behaviors to microstructures of multi-phase alloys based on 316L stainless steel and HT9 (410 stainless steel was used as a substitute) with added Mo, Ni, and/or Mn, and (4) modeling the corrosion behaviors and rates of several alloy/oxide composite materials made with added lanthanide and uranium oxides. These analyses show the corrosion behaviors of the alloy/ceramic composite materials are very similar to the corrosion behaviors of multi-phase alloy waste forms, and that the presence of oxide inclusions does not impact the corrosion behaviors of the alloy phases. Mixing with metallic waste streams is beneficial to lanthanide and uranium oxides in that they react with Zr in the fuel waste to form highly durable zirconates. The measured corrosion behaviors suggest properly formulated composite materials would be suitable waste forms for combined metallic and oxide waste streams generated during electrometallurgical reprocessing of spent nuclear fuel. Electrochemical methods are suitable for evaluating the durability and modeling long-term behavior of composite waste forms: the degradation model developed for metallic waste forms can be applied to the alloy phases formed in the composite and an affinity-based mineral dissolution model can be applied to the ceramic phases.« less

Equilibrium Temperature Profiles within Fission Product Waste Forms

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

Kaminski, Michael D.

2016-10-01

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

Strategic Minimization of High Level Waste from Pyroprocessing of Spent Nuclear Fuel

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

Simpson, Michael F.; Benedict, Robert W.

The pyroprocessing of spent nuclear fuel results in two high-level waste streams--ceramic and metal waste. Ceramic waste contains active metal fission product-loaded salt from the electrorefining, while the metal waste contains cladding hulls and undissolved noble metals. While pyroprocessing was successfully demonstrated for treatment of spent fuel from Experimental Breeder Reactor-II in 1999, it was done so without a specific objective to minimize high-level waste generation. The ceramic waste process uses “throw-away” technology that is not optimized with respect to volume of waste generated. In looking past treatment of EBR-II fuel, it is critical to minimize waste generation for technologymore » developed under the Global Nuclear Energy Partnership (GNEP). While the metal waste cannot be readily reduced, there are viable routes towards minimizing the ceramic waste. Fission products that generate high amounts of heat, such as Cs and Sr, can be separated from other active metal fission products and placed into short-term, shallow disposal. The remaining active metal fission products can be concentrated into the ceramic waste form using an ion exchange process. It has been estimated that ion exchange can reduce ceramic high-level waste quantities by as much as a factor of 3 relative to throw-away technology.« less

Irradiation effect on leaching behavior and form of heavy metals in fly ash of municipal solid waste incinerator.

PubMed

Nam, Sangchul; Namkoong, Wan

2012-01-15

Fly ash from a municipal solid waste incinerator (MSWI) is commonly classified as hazardous waste. High-energy electron beam irradiation systems have gained popularity recently as a clean and promising technology to remove environmental pollutants. Irradiation effects on leaching behavior and form of heavy metals in MSWI fly ash have not been investigated in any significant detail. An electron beam accelerator was used in this research. Electron beam irradiation on fly ash significantly increased the leaching potential of heavy metals from fly ash. The amount of absorbed dose and the metal species affected leaching behavior. When electron beam irradiation intensity increased gradually up to 210 kGy, concentration of Pb and Zn in the leachate increased linearly as absorbed dose increased, while that of Cu underwent no significant change. Concentration of Pb and Zn in the leachate increased up to 15.5% (10.7 mg/kg), and 35.6% (9.6 mg/kg) respectively. However, only 4.8% (0.3mg/kg) increase was observed in the case of Cu. The results imply that irradiation has significant effect on the leaching behavior of heavy metals in fly ash, and the effect is quite different among the metal species tested in this study. A commonly used sequential extraction analysis which can classify a metal species into five forms was conducted to examine any change in metal form in the irradiated fly ash. Notable change in metal form in fly ash was observed when fly ash was irradiated. Change in Pb form was much greater than that of Cu form. Change in metal form was related to leaching potential of the metals. Concentration of heavy metal in leachate was positively related to the exchangeable form which is the most mobile. It may be feasible to treat fly ash by electron beam irradiation for selective recovery of valuable metals or for pretreatment prior to conventional processes. Copyright © 2011 Elsevier B.V. All rights reserved.

Options for the Separation and Immobilization of Technetium

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

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

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

Development of Alternative Technetium Waste Forms

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

Czerwinski, Kenneth

2013-09-13

The UREX+1 process is under consideration for the separation of transuranic elements from spent nuclear fuel. The first steps of this process extract the fission product technicium-99 ({sup 99}Tc) into an organic phase containing tributylphosphate together with uranium. Treatment of this stream requires the separation of Tc from U and placement into a suitable waste storage form. A potential candidate waste form involves immobilizing the Tc as an alloy with either excess metallic zirconium or stainless steel. Although Tc-Zr alloys seem to be promising waste forms, alternative materials must be investigated. Innovative studies related to the synthesis and behavior ofmore » a different class of Tc materials will increase the scientific knowledge related to development of Tc waste forms. These studies will also provide a better understanding of the behavior of {sup 99}Tc in repository conditions. A literature survey has selected promising alternative waste forms for further study: technetium metallic alloys, nitrides, oxides, sulfides, and pertechnetate salts. The goals of this project are to 1) synthesize and structurally characterize relevant technetium materials that may be considered as waste forms, 2) investigate material behavior in solution under different conditions of temperature, electrochemical potential, and radiation, and 3) predict the long-term behavior of these materials.« less

Urban Mining of E-Waste is Becoming More Cost-Effective Than Virgin Mining.

PubMed

Zeng, Xianlai; Mathews, John A; Li, Jinhui

2018-04-17

Stocks of virgin-mined materials utilized in linear economic flows continue to present enormous challenges. E-waste is one of the fastest growing waste streams, and threatens to grow into a global problem of unmanageable proportions. An effective form of management of resource recycling and environmental improvement is available, in the form of extraction and purification of precious metals taken from waste streams, in a process known as urban mining. In this work, we demonstrate utilizing real cost data from e-waste processors in China that ingots of pure copper and gold could be recovered from e-waste streams at costs that are comparable to those encountered in virgin mining of ores. Our results are confined to the cases of copper and gold extracted and processed from e-waste streams made up of recycled TV sets, but these results indicate a trend and potential if applied across a broader range of e-waste sources and metals extracted. If these results can be extended to other metals and countries, they promise to have positive impact on waste disposal and mining activities globally, as the circular economy comes to displace linear economic pathways.

Metals bioleaching from electronic waste by Chromobacterium violaceum and Pseudomonads sp.

PubMed

Pradhan, Jatindra Kumar; Kumar, Sudhir

2012-11-01

These days, electronic waste needs to be taken into consideration due to its materials content, but due to the heterogeneity of the metals present, reprocessing of electronic waste is quite limited. The bioleaching of metals from electronic waste was investigated by using cyanogenic bacterial strains (Chromobacterium violaceum, Pseudomonas aeruginosa and Pseudomonas fluorescens). A two-step bioleaching process was followed under cyanide-forming conditions for maximum metals mobilization. Both single and mixed cultures of cyanogenic bacteria were able to mobilize metals from electronic waste with different efficiencies. In all the flasks in which high metal mobilizations were observed, the consequent biomass productions were also high. Pseudomonas aeruginosa was applied in the bioleaching process for the first time and this achieved its bioleaching ability of mobilization of metals from electronic waste. Chromobacterium violaceum as a single culture and a mixture of C. violaceum and P. aeruginosa exhibited maximum metal mobilization. Chromobacterium violaceum was capable of leaching more than 79, 69, 46, 9 and 7% of Cu, Au, Zn, Fe and Ag, respectively at an electronic waste concentration of 1% w/v. Moreover, the mixture of C. violaceum and P. aeruginosa exhibited metals leaching of more than 83, 73, 49, 13 and 8% of total Cu, Au, Zn, Fe, and Ag, respectively. Precious metals were mobilized through bioleaching which might be considered as an industrial application for recycling of electronic waste in the near future.

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

NASA Astrophysics Data System (ADS)

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

2017-06-01

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

Vitrification of organics-containing wastes

DOEpatents

Bickford, Dennis F.

1997-01-01

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

Vitrification of organics-containing wastes

DOEpatents

Bickford, D.F.

1997-09-02

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

Metal Recovery from Industrial Solid Waste — Contribution to Resource Sustainability

NASA Astrophysics Data System (ADS)

Yang, Yongxiang

Increased demand of metals has driven the accelerated mining and metallurgical production in recent years, causing fast depletion of primary metals resources. On the contrary, the mining and metallurgical industry generates large amount of solid residues and waste such as tailings, slags, flue dust and leach residues, with relative low valuable metal contents. On the other hand, end-of-life (EoL) consumer products form another significant resources. The current technology and processes for primary metals production are not readily applicable for direct metals extraction from these waste materials, and special adaptation and tailor-made processes are required. In the present paper, various solid waste resources are reviewed, and current technologies and R&D trends are discussed. The recent research at author's group is illustrated for providing potential solutions to future resource problems, including metal recovery from MSW incinerator bottom ashes, zinc recovery from industrial ashes and residues, and rare earth metals recovery from EoL permanent magnets.

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

PubMed

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

2016-07-01

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

Generation of copper rich metallic phases from waste printed circuit boards.

PubMed

Cayumil, R; Khanna, R; Ikram-Ul-Haq, M; Rajarao, R; Hill, A; Sahajwalla, V

2014-10-01

The rapid consumption and obsolescence of electronics have resulted in e-waste being one of the fastest growing waste streams worldwide. Printed circuit boards (PCBs) are among the most complex e-waste, containing significant quantities of hazardous and toxic materials leading to high levels of pollution if landfilled or processed inappropriately. However, PCBs are also an important resource of metals including copper, tin, lead and precious metals; their recycling is appealing especially as the concentration of these metals in PCBs is considerably higher than in their ores. This article is focused on a novel approach to recover copper rich phases from waste PCBs. Crushed PCBs were heat treated at 1150°C under argon gas flowing at 1L/min into a horizontal tube furnace. Samples were placed into an alumina crucible and positioned in the cold zone of the furnace for 5 min to avoid thermal shock, and then pushed into the hot zone, with specimens exposed to high temperatures for 10 and 20 min. After treatment, residues were pulled back to the cold zone and kept there for 5 min to avoid thermal cracking and re-oxidation. This process resulted in the generation of a metallic phase in the form of droplets and a carbonaceous residue. The metallic phase was formed of copper-rich red droplets and tin-rich white droplets along with the presence of several precious metals. The carbonaceous residue was found to consist of slag and ∼30% carbon. The process conditions led to the segregation of hazardous lead and tin clusters in the metallic phase. The heat treatment temperature was chosen to be above the melting point of copper; molten copper helped to concentrate metallic constituents and their separation from the carbonaceous residue and the slag. Inert atmosphere prevented the re-oxidation of metals and the loss of carbon in the gaseous fraction. Recycling e-waste is expected to lead to enhanced metal recovery, conserving natural resources and providing an environmentally sustainable solution to the management of waste products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative thermodynamic and experimental study of some heavy metal behaviors during automotive shredder residues incineration

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

Trouve, G.; Kauffmann, A.; Delfosse, L.

1998-12-31

Experimental and theoretical studies of the behavior of some heavy metals were undertaken during Automotive Shredder Residues (ASR) incineration. A thermodynamic study at equilibrium was performed using a software minimizing the free Gibbs energy. The metals studied were barium, copper, lead and zinc. The studies were performed mostly at two temperatures: 1123 and 1373 K. The thermodynamic study showed that the chlorine content is the most important parameter influencing the volatility of the studied metals. It also showed that in default of chlorine in a system containing several metals, barium chloride in its condensed form is the most easily formed.more » Other metals remained in their metallic form or in the form of oxides. The presence of hydrogen in the system has a general limiting influence on the metal volatility because, especially at high temperatures, hydrogen chloride is more likely to be formed. In the experimental field, the behaviors of metals were studied using commercial polymers as waste models: a PVC mastic, a polyurethane mastic and a rubber powder. Copper and barium presented a non volatile behavior during the incineration of waste matrixes as ASR, being present also in residual ash. On the other hand, lead was completely formed in the gas phase and zinc showed an equal partitioning between the two principal phases of the treatment.« less

Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

PubMed

Rola, Kaja; Osyczka, Piotr; Kafel, Alina

2016-02-01

Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

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

PubMed

Bingham, P A; Hand, R J

2005-03-17

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

Process for electrolytically preparing uranium metal

DOEpatents

Haas, Paul A.

1989-01-01

A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

Process for electrolytically preparing uranium metal

DOEpatents

Haas, Paul A.

1989-08-01

A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

Incineration, pyrolysis and gasification of electronic waste

NASA Astrophysics Data System (ADS)

Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

2017-11-01

Three high temperature processes of the electronic waste processing: smelting/incineration, pyrolysis and gasification were shortly discussed. The most distinctive feature of electronic waste is complexity of components and their integration. This type of waste consists of polymeric materials and has high content of valuable metals that could be recovered. The purpose of thermal treatment of electronic waste is elimination of plastic components (especially epoxy resins) while leaving non-volatile mineral and metallic phases in more or less original forms. Additionally, the gaseous product of the process after cleaning may be used for energy recovery or as syngas.

Treatment of electronic waste to recover metal values using thermal plasma coupled with acid leaching--a response surface modeling approach.

PubMed

Rath, Swagat S; Nayak, Pradeep; Mukherjee, P S; Roy Chaudhury, G; Mishra, B K

2012-03-01

The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency. Copyright © 2011 Elsevier Ltd. All rights reserved.

Metals Recovery from Artificial Ore in Case of Printed Circuit Boards, Using Plasmatron Plasma Reactor

PubMed Central

Szałatkiewicz, Jakub

2016-01-01

This paper presents the investigation of metals production form artificial ore, which consists of printed circuit board (PCB) waste, processed in plasmatron plasma reactor. A test setup was designed and built that enabled research of plasma processing of PCB waste of more than 700 kg/day scale. The designed plasma process is presented and discussed. The process in tests consumed 2 kWh/kg of processed waste. Investigation of the process products is presented with their elemental analyses of metals and slag. The average recovery of metals in presented experiments is 76%. Metals recovered include: Ag, Au, Pd, Cu, Sn, Pb, and others. The chosen process parameters are presented: energy consumption, throughput, process temperatures, and air consumption. Presented technology allows processing of variable and hard-to-process printed circuit board waste that can reach up to 100% of the input mass. PMID:28773804

Metals Recovery from Artificial Ore in Case of Printed Circuit Boards, Using Plasmatron Plasma Reactor.

PubMed

Szałatkiewicz, Jakub

2016-08-10

This paper presents the investigation of metals production form artificial ore, which consists of printed circuit board (PCB) waste, processed in plasmatron plasma reactor. A test setup was designed and built that enabled research of plasma processing of PCB waste of more than 700 kg/day scale. The designed plasma process is presented and discussed. The process in tests consumed 2 kWh/kg of processed waste. Investigation of the process products is presented with their elemental analyses of metals and slag. The average recovery of metals in presented experiments is 76%. Metals recovered include: Ag, Au, Pd, Cu, Sn, Pb, and others. The chosen process parameters are presented: energy consumption, throughput, process temperatures, and air consumption. Presented technology allows processing of variable and hard-to-process printed circuit board waste that can reach up to 100% of the input mass.

Informal e-waste recycling: environmental risk assessment of heavy metal contamination in Mandoli industrial area, Delhi, India.

PubMed

Pradhan, Jatindra Kumar; Kumar, Sudhir

2014-01-01

Nowadays, e-waste is a major source of environmental problems and opportunities due to presence of hazardous elements and precious metals. This study was aimed to evaluate the pollution risk of heavy metal contamination by informal recycling of e-waste. Environmental risk assessment was determined using multivariate statistical analysis, index of geoaccumulation, enrichment factor, contamination factor, degree of contamination and pollution load index by analysing heavy metals in surface soils, plants and groundwater samples collected from and around informal recycling workshops in Mandoli industrial area, Delhi, India. Concentrations of heavy metals like As (17.08 mg/kg), Cd (1.29 mg/kg), Cu (115.50 mg/kg), Pb (2,645.31 mg/kg), Se (12.67 mg/kg) and Zn (776.84 mg/kg) were higher in surface soils of e-waste recycling areas compared to those in reference site. Level exceeded the values suggested by the US Environmental Protection Agency (EPA). High accumulations of heavy metals were also observed in the native plant samples (Cynodon dactylon) of e-waste recycling areas. The groundwater samples collected form recycling area had high heavy metal concentrations as compared to permissible limit of Indian Standards and maximum allowable limit of WHO guidelines for drinking water. Multivariate analysis and risk assessment studies based on total metal content explains the clear-cut differences among sampling sites and a strong evidence of heavy metal pollution because of informal recycling of e-waste. This study put forward that prolonged informal recycling of e-waste may accumulate high concentration of heavy metals in surface soils, plants and groundwater, which will be a matter of concern for both environmental and occupational hazards. This warrants an immediate need of remedial measures to reduce the heavy metal contamination of e-waste recycling sites.

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

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

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

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

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

DOE PAGES

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

2017-06-01

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

Decomposition Mechanism and Decomposition Promoting Factors of Waste Hard Metal for Zinc Decomposition Process (ZDP)

NASA Astrophysics Data System (ADS)

Pee, J. H.; Kim, Y. J.; Kim, J. Y.; Seong, N. E.; Cho, W. S.; Kim, K. J.

2011-10-01

Decomposition promoting factors and decomposition mechanism in the zinc decomposition process of waste hard metals which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility amount was suppressed and zinc steam pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP. Reaction was done for 2 hrs at 650 °C, which 100 % decomposed the waste hard metals that were over 30 mm thick. As for the separation-decomposition of waste hard metals, zinc melted alloy formed a liquid composed of a mixture of γ-β1 phase from the cobalt binder layer (reaction interface). The volume of reacted zone was expanded and the waste hard metal layer was decomposed-separated horizontally from the hard metal. Zinc used in the ZDP process was almost completely removed-collected by decantation and volatilization-collection process at 1000 °C. The small amount of zinc remaining in the tungsten carbide-cobalt powder which was completely decomposed was fully removed by using phosphate solution which had a slow cobalt dissolution speed.

Lauryl Amine as heavy metal collector of boiler ash from pulp and paper mill waste

NASA Astrophysics Data System (ADS)

Sembiring, M. P.; Kaban, J.; Bangun, N.; Saputra, E.

2018-04-01

Theincreasing of demand of pulp and paper products, will following with the growing the pulp and paper industryand generate significant mill waste. The total waste reached 1/3 of the amount raw materials used and ash boiler is the waste with the largest percentage of 52%. For that it takes effort to manage the existing waste. The boiler ash contained the chemical elements, it can be utilized such as fertilizer, because it also contains transition metals in form of heavy metal such as Cadmium (Cd), Cobalt (Co), Chrome (Cr), Cupprum (Cu), Ferrum (Fe), Nickel (Ni), and Zinc (Zn), the use of boiler ash must follow the threshold specified by the Government. Several studies have been undertaken to reduce and extract heavy metals from ash and sand of the boiler by using carbon dioxide as its ligand. Eelectrochemical method was used to remove and recovery of heavy metals from the incenerator. This study focused on removal of heavy metals using Lauryl Amine as collector and three solvents namely Dichloromethane, Ethanol and n-Hexane. The treatmentswas able to extract the heavy metal and generally reduce the heavy metal content of ash boiler pulp and paper mill waste. The combination treatment used toreduce the heavy metal content of 5 gram Lauryl Amine collector in Dichloromethane solvent for 4 hours process time.

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

Cayumil, R.; Khanna, R., E-mail: ritakhanna@unsw.edu.au; Ikram-Ul-Haq, M.

Highlights: • Recycling and material recovery from waste printed circuit boards is very complex. • Thermoset polymers, ceramics and metals are present simultaneously in waste PCBs. • Heat treatment of PCBs was carried out at 1150 °C under inert conditions. • Various metallic phases could be segregated out as copper based metallic droplets. • Carbon and ceramics residues can be further recycled in a range of applications. - Abstract: The rapid consumption and obsolescence of electronics have resulted in e-waste being one of the fastest growing waste streams worldwide. Printed circuit boards (PCBs) are among the most complex e-waste, containingmore » significant quantities of hazardous and toxic materials leading to high levels of pollution if landfilled or processed inappropriately. However, PCBs are also an important resource of metals including copper, tin, lead and precious metals; their recycling is appealing especially as the concentration of these metals in PCBs is considerably higher than in their ores. This article is focused on a novel approach to recover copper rich phases from waste PCBs. Crushed PCBs were heat treated at 1150 °C under argon gas flowing at 1 L/min into a horizontal tube furnace. Samples were placed into an alumina crucible and positioned in the cold zone of the furnace for 5 min to avoid thermal shock, and then pushed into the hot zone, with specimens exposed to high temperatures for 10 and 20 min. After treatment, residues were pulled back to the cold zone and kept there for 5 min to avoid thermal cracking and re-oxidation. This process resulted in the generation of a metallic phase in the form of droplets and a carbonaceous residue. The metallic phase was formed of copper-rich red droplets and tin-rich white droplets along with the presence of several precious metals. The carbonaceous residue was found to consist of slag and ∼30% carbon. The process conditions led to the segregation of hazardous lead and tin clusters in the metallic phase. The heat treatment temperature was chosen to be above the melting point of copper; molten copper helped to concentrate metallic constituents and their separation from the carbonaceous residue and the slag. Inert atmosphere prevented the re-oxidation of metals and the loss of carbon in the gaseous fraction. Recycling e-waste is expected to lead to enhanced metal recovery, conserving natural resources and providing an environmentally sustainable solution to the management of waste products.« less

Metallic elements occurrences within metallic fragments in the municipal waste incineration bottom ash

NASA Astrophysics Data System (ADS)

Kowalski, Piotr; Kasina, Monika; Michalik, Marek

2017-04-01

Bottom ash (BA) from municipal solid waste incineration (MSWI) is composed of grainy ash material, residual components and metallic fragments (from few µm up to 3-5 cm). Its mineral and chemical composition is related to the composition of the waste stream in the incinerator operational area. Wide use of thermal techniques in management of solid waste makes important the studies on valuable components and their distribution within the material in terms of their further processing. By using various valorization or extraction techniques it is possible to extend the range of its possible further application. To investigate metallic elements distribution within metallic fragments of the MSWI BA material produced in municipal waste incineration plant in Poland were collected in 2015 and 2016. BA and its components were investigated using spectroscopic methods of chemical analysis: ICP-OES, ICP-MS, LECO and EDS (used for microanalysis during SEM observations). BA is a material rich in Si (22.5 wt%), Ca (13.4 wt%), Fe (4 wt%), Al (5.2 wt%) and Na (3.5 wt%), composed of equal part of amorphous (silicate glass dominated) and crystalline phase (rich in silicates, aluminosilicates, oxides of non- and metallic elements and sulphates). The content of metallic elements (Al, Fe, Mg, Ti, Mn, Cr, Ni, Sc, Mo, Cu, Pb, Zn, Sn) is 11.5 wt% with domination of Al (5.2 wt%) and Fe (4 wt%) and elevated values of Mg (1 wt%), Ti (0.54 wt%), Cu (0.26 wt%) and Zn (0.27 wt%) (Kowalski et al., 2016). They were mostly concentrated in the form of metallic fragments, mainly as metallic inclusions in the size of 1-20 µm and separated metallic grains in the size of 50-300 µm. Metallic fragments present in the BA are characterized by their composition heterogeneity and various oxygen content. Fragments are rarely composed of single metallic element and usually in their composition up to few main elements dominated over others. The most common were Fe-, Al- and Zn-rich fragments forming respectively 70%, 15% and 5% of the total amount of fragments. Fe occurred mainly as component of metallic inclusions and separate grains. Al was mostly present in metallic fragments on grains boundaries and also and as separate grains (often oxidised), moreover Al was important component of aluminosilicates and amorphous phase. Zn-rich metallic fragments were mostly in the form of separate grains. In complex composition of metallic fragments some regularities in elements co-occurrences were observed: Fe often co-existed with Si, Ca, P, Al and Ti; Al co-occurred with Fe, Si and Ca; Zn co-existed with Ca, Al and Si. Forms and composition of metallic fragments allows to evaluate them as potential polymetallic resource, however an economically reasonable extraction techniques must be applied. Acknowledgment Research was funded by Polish National Science Centre (NCN). Scientific grant No. UMO-2014/15/B/ST10/04171. Reference Kowalski, P.R., Kasina, M. and Michalik M.: Metallic elements fractionation in municipal solid waste incineration residues, Energy Procedia, 97, 31-36, doi: 10.1016/j.egypro.2016.10.013, 2016.

[Impact of waste landfills in the Saratov region on the sanitary condition of the soil].

PubMed

Eremin, V N; Reshetnikov, M V; Sheshnev, A S

Monitoring of environment in regions of the location of waste landfills includes the implementation of the control over a sanitary condition of soils. The main origins of the spread ofpollutants into soils are the solid particles from aerosol emissions from the functioning of landfills transmitted to surrounding territories. Within zones of the impact of three largest waste landfills in the Saratov region (Aleksandrovsky, Guselsky in the city of Saratov and Balakovsky in the city of Balakovo) there were taken 152 soil samples. According to results of the estimation in soil concentration of gross and motile forms of heavy metals of the first (Zn, Cd, Ni) and the second danger classes (Cu, Cr, Pb) there was performed the analysis of coefficients of danger- K0 and total coefficients ofpollution - Zc. There was executed the assessment of both a sanitary and hygienic condition of soils and degree of danger ofpollution. The most contrast areal features of the distribution of the danger coefficient - Ko in soils are characteristic for motile forms of heavy metals. For all three studied objects persistently there is stood out the dangerous and areal pollution of soils by association of Ni and Cu . The danger ofpollution of soils by gross forms of heavy metals is minimum. The coefficient of total pollution of Zc exceeds admissible level on motile forms of heavy metals only for the soils surrounding the Balakovo landfill. In zones of the impact of waste landfills there are located the processed lands with an adverse sanitary and hygienic condition of soils. In the region of the Guselsky object soils of the processed agricultural grounds are dangerously polluted by motile forms of Ni and Cu. In vicinities of the Balakovo waste landfill considerable areas of private gardening enterprises are dangerously polluted by the motile forms of Ni, Cu and Zn.

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.

Method for distinctive estimation of stored acidity forms in acid mine wastes.

PubMed

Li, Jun; Kawashima, Nobuyuki; Fan, Rong; Schumann, Russell C; Gerson, Andrea R; Smart, Roger St C

2014-10-07

Jarosites and schwertmannite can be formed in the unsaturated oxidation zone of sulfide-containing mine waste rock and tailings together with ferrihydrite and goethite. They are also widely found in process wastes from electrometallurgical smelting and metal bioleaching and within drained coastal lowland soils (acid-sulfate soils). These secondary minerals can temporarily store acidity and metals or remove and immobilize contaminants through adsorption, coprecipitation, or structural incorporation, but release both acidity and toxic metals at pH above about 4. Therefore, they have significant relevance to environmental mineralogy through their role in controlling pollutant concentrations and dynamics in contaminated aqueous environments. Most importantly, they have widely different acid release rates at different pHs and strongly affect drainage water acidity dynamics. A procedure for estimation of the amounts of these different forms of nonsulfide stored acidity in mining wastes is required in order to predict acid release rates at any pH. A four-step extraction procedure to quantify jarosite and schwertmannite separately with various soluble sulfate salts has been developed and validated. Corrections to acid potentials and estimation of acid release rates can be reliably based on this method.

Iron and aluminium oxides containing industrial wastes as adsorbents of heavy metals: Application possibilities and limitations.

PubMed

Jacukowicz-Sobala, Irena; Ociński, Daniel; Kociołek-Balawejder, Elżbieta

2015-07-01

Industrial wastes with a high iron or aluminium oxide content are produced in huge quantities as by-products of water treatment (water treatment residuals), bauxite processing (red mud) and hard and brown coal burning in power plants (fly ash). Although they vary in their composition, the wastes have one thing in common--a high content of amorphous iron and/or aluminium oxides with a large specific surface area, whereby this group of wastes shows very good adsorbability towards heavy metals, arsenates, selenates, etc. But their physical form makes their utilisation quite difficult, since it is not easy to separate the spent sorbent from the solution and high bed hydraulic resistances occur in dynamic regime processes. Nevertheless, because of the potential benefits of utilising the wastes in industrial effluent treatment, this issue attracts much attention today. This study describes in detail the waste generation processes, the chemical structure of the wastes, their physicochemical properties, and the mechanisms of fixing heavy metals and semimetals on the surface of iron and aluminium oxides. Typical compositions of wastes generated in selected industrial plants are given. A detailed survey of the literature on the adsorption applications of the wastes, including methods of their thermal and chemical activation, as well as regeneration of the spent sorbents, is presented. The existing and potential ways of modifying the physical form of the discussed group of wastes, making it possible to overcome the basic limitation on their practical use, are discussed. © The Author(s) 2015.

Agricultural waste material as potential adsorbent for sequestering heavy metal ions from aqueous solutions - a review.

PubMed

Sud, Dhiraj; Mahajan, Garima; Kaur, M P

2008-09-01

Heavy metal remediation of aqueous streams is of special concern due to recalcitrant and persistency of heavy metals in environment. Conventional treatment technologies for the removal of these toxic heavy metals are not economical and further generate huge quantity of toxic chemical sludge. Biosorption is emerging as a potential alternative to the existing conventional technologies for the removal and/or recovery of metal ions from aqueous solutions. The major advantages of biosorption over conventional treatment methods include: low cost, high efficiency, minimization of chemical or biological sludge, regeneration of biosorbents and possibility of metal recovery. Cellulosic agricultural waste materials are an abundant source for significant metal biosorption. The functional groups present in agricultural waste biomass viz. acetamido, alcoholic, carbonyl, phenolic, amido, amino, sulphydryl groups etc. have affinity for heavy metal ions to form metal complexes or chelates. The mechanism of biosorption process includes chemisorption, complexation, adsorption on surface, diffusion through pores and ion exchange etc. The purpose of this review article is to provide the scattered available information on various aspects of utilization of the agricultural waste materials for heavy metal removal. Agricultural waste material being highly efficient, low cost and renewable source of biomass can be exploited for heavy metal remediation. Further these biosorbents can be modified for better efficiency and multiple reuses to enhance their applicability at industrial scale.

GeoMelt{sup R} ICV{sup TM} Treatment of Sellafield Pond Solids Waste - 13414

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

Witwer, Keith; Woosley, Steve; Campbell, Brett

2013-07-01

Kurion, Inc., in partnership with AMEC Ltd., is demonstrating its GeoMelt{sup R} In-Container Vitrification (ICV){sup TM} Technology to Sellafield Ltd. (SL). SL is evaluating the proposition of directly converting a container (skip/box/drum) of raw solid ILW into an immobilized waste form using thermal treatment, such that the resulting product is suitable for interim storage at Sellafield and subsequent disposal at a future Geological Disposal Facility. Potential SL feed streams include sludges, ion-exchange media, sand, plutonium contaminated material, concrete, uranium, fuel cladding, soils, metals, and decommissioning wastes. The solid wastes have significant proportions of metallic constituents in the form of containers,more » plant equipment, structural material and swarf arising from the nuclear operations at Sellafield. GeoMelt's proprietary ICV process was selected for demonstration, with the focus being high and reactive metal wastes arising from solid ILW material. A composite surrogate recipe was used to demonstrate the technology towards treating waste forms of diverse types and shapes, as well as those considered difficult to process; all the while requiring few (if any) pre-treatment activities. Key strategic objectives, along with their success criterion, were established by SL for this testing, namely: 1. Passivate and stabilize the raw waste simulant, as demonstrated by the entire quantity of material being vitrified, 2. Immobilize the radiological and chemo-toxic species, as demonstrated via indicative mass balance using elemental analyses from an array of samples, 3. Production of an inert and durable product as evidenced by transformation of reactive metals to their inert oxide forms and satisfactory leachability results using PCT testing. Two tests were performed using the GeoMelt Demonstration Unit located at AMEC's Birchwood Park Facilities in the UK. Post-melt examination of the first test indicated some of the waste simulant had not fully processed, due to insufficient processing time and melt temperature. A second test, incorporating operational experience from the first test, was performed and resulted in all of the 138 kg of feed material being treated. The waste simulant portion, at 41 kg, constituted 30 wt% of the total feed mass, with over 90% of this being made up of various reactive and non-reactive metals. The 95 liters of staged material was volume reduced to 41 liters, providing a 57% overall feed to product volume reduction in a fully passivated two-phase glass/metal product. The GeoMelt equipment operated as designed, vitrifying the entire batch of waste simulant. Post-melt analytical testing verified that 91-99+% of the radiological tracer metals were uniformly distributed within the glass/cast refractory/metal product, and the remaining fraction was captured in the offgas filtration systems. PCT testing of the glass and inner refractory liner showed leachability results that outperform the DOE regulatory limit of 2 g/m{sup 2} for the radiological species of interest (Sr, Ru, Cs, Eu, Re), and by more than an order of magnitude better for standard reference analytes (B, Na, Si). (authors)« less

Study on the behavior of heavy metals during thermal treatment of municipal solid waste (MSW) components.

PubMed

Yu, Jie; Sun, Lushi; Wang, Ben; Qiao, Yu; Xiang, Jun; Hu, Song; Yao, Hong

2016-01-01

Laboratory experiments were conducted to investigate the volatilization behavior of heavy metals during pyrolysis and combustion of municipal solid waste (MSW) components at different heating rates and temperatures. The waste fractions comprised waste paper (Paper), disposable chopstick (DC), garbage bag (GB), PVC plastic (PVC), and waste tire (Tire). Generally, the release trend of heavy metals from all MSW fractions in rapid-heating combustion was superior to that in low-heating combustion. Due to the different characteristics of MSW fractions, the behavior of heavy metals varied. Cd exhibited higher volatility than the rest of heavy metals. For Paper, DC, and PVC, the vaporization of Cd can reach as high as 75% at 500 °C in the rapid-heating combustion due to violent combustion, whereas a gradual increase was observed for Tire and GB. Zn and Pb showed a moderate volatilization in rapid-heating combustion, but their volatilities were depressed in slow-heating combustion. During thermal treatment, the additives such as kaolin and calcium can react or adsorb Pb and Zn forming stable metal compounds, thus decreasing their volatilities. The formation of stable compounds can be strengthened in slow-heating combustion. The volatility of Cu was comparatively low in both high and slow-heating combustion partially due to the existence of Al, Si, or Fe in residuals. Generally, in the reducing atmosphere, the volatility of Cd, Pb, and Zn was accelerated for Paper, DC, GB, and Tire due to the formation of elemental metal vapor. TG analysis also showed the reduction of metal oxides by chars forming elemental metal vapor. Cu2S was the dominant Cu species in reducing atmosphere below 900 °C, which was responsible for the low volatility of Cu. The addition of PVC in wastes may enhance the release of heavy metals, while GB and Tire may play an opposite effect. In controlling heavy metal emission, aluminosilicate- and calcium-based sorbents can be co-treated with fuels. Moreover, pyrolysis can be a better choice for treatment of solid waster in terms of controlling heavy metals. PVC and Tire should be separated and treated individually due to high possibility of heavy metal emission. This information may then serve as a guideline for the design of the subsequent gas cleaning plant, necessary to reduce the final emissions to the atmosphere to an acceptable level.

Effective Recovery of Vanadium from Oil Refinery Waste into Vanadium-Based Metal-Organic Frameworks.

PubMed

Zhan, Guowu; Ng, Wei Cheng; Lin, Wenlin Yvonne; Koh, Shin Nuo; Wang, Chi-Hwa

2018-03-06

Carbon black waste, an oil refinery waste, contains a high concentration of vanadium(V) leftover from the processing of crude oil. For the sake of environmental sustainability, it is therefore of interest to recover the vanadium as useful products instead of disposing of it. In this work, V was recovered in the form of vanadium-based metal-organic frameworks (V-MOFs) via a novel pathway by using the leaching solution of carbon black waste instead of commercially available vanadium chemicals. Two different types of V-MOFs with high levels of crystallinity and phase purity were fabricated in very high yields (>98%) based on a coordination modulation method. The V-MOFs exhibited well-defined and controlled shapes such as nanofibers (length: > 10 μm) and nanorods (length: ∼270 nm). Furthermore, the V-MOFs showed high catalytic activities for the oxidation of benzyl alcohol to benzaldehyde, indicating the strong potential of the waste-derived V-MOFs in catalysis applications. Overall, our work offers a green synthesis pathway for the preparation of V-MOFs by using heavy metals of industrial waste as the metal source.

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.

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.

Encapsulation of aluminium in geopolymers produced from metakaolin

NASA Astrophysics Data System (ADS)

Kuenzel, C.; Neville, T. P.; Omakowski, T.; Vandeperre, L.; Boccaccini, A. R.; Bensted, J.; Simons, S. J. R.; Cheeseman, C. R.

2014-04-01

Magnox swarf contaminated with trace levels of Al metal is an important UK legacy waste originated from the fuel rod cladding system used in Magnox nuclear power stations. Composite cements made from Portland cement and blast furnace slag form a potential encapsulation matrix. However the high pH of this system causes the Al metal to corrode causing durability issues. Geopolymers derived from metakaolin are being investigated as an alternative encapsulation matrix for Magnox swarf waste and the corrosion kinetics and surface interactions of Al with metakaolin geopolymer are reported in this paper. It is shown that the pH of the geopolymer paste can be controlled by the selection of metakaolin and the sodium silicate solution used to form the geopolymer. A decrease in pH of the activation solution reduces corrosion of the Al metal and increases the stability of bayerite and gibbsite layers formed on the Al surface. The bayerite and gibbsite act as a passivation layer which inhibits further corrosion and mitigates H2 generation. The research shows that optimised metakaolin geopolymers have potential to be used to encapsulate legacy Magnox swarf wastes.

Ice electrode electrolytic cell

DOEpatents

Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

1993-04-06

This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

Ice electrode electrolytic cell

DOEpatents

Glenn, David F.; Suciu, Dan F.; Harris, Taryl L.; Ingram, Jani C.

1993-01-01

This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

SRS stainless steel beneficial reuse program

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

Boettinger, W.L.

1997-02-01

The US Department of Energy`s (DOE) Savannah River Site (SRS) has thousands of tons of stainless steel radioactive scrap metal (RSNI). Much of the metal is volumetrically contaminated. There is no {open_quotes}de minimis{close_quotes} free release level for volumetric material, and therefore no way to recycle the metal into the normal commercial market. If declared waste, the metal would qualify as low level radioactive waste (LLW) and ultimately be dispositioned through shallow land buried at a cost of millions of dollars. The metal however could be recycled in a {open_quotes}controlled release{close_quote} manner, in the form of containers to hold other typesmore » of radioactive waste. This form of recycle is generally referred to as {open_quotes}Beneficial Reuse{close_quotes}. Beneficial reuse reduces the amount of disposal space needed and reduces the need for virgin containers which would themselves become contaminated. Stainless steel is particularly suited for long term storage because of its resistance to corrosion. To assess the practicality of stainless steel RSM recycle the SRS Benficial Reuse Program began a demonstration in 1994, funded by the DOE Office of Science and Technology. This paper discusses the experiences gained in this program.« less

Secondary Waste Form Screening Test Results—THOR® Fluidized Bed Steam Reforming Product in a Geopolymer Matrix

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

Pires, Richard P.; Westsik, Joseph H.; Serne, R. Jeffrey

2011-07-14

Screening tests are being conducted to evaluate waste forms for immobilizing secondary liquid wastes from the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Plans are underway to add a stabilization treatment unit to the Effluent Treatment Facility to provide the needed capacity for treating these wastes from WTP. The current baseline is to use a Cast Stone cementitious waste form to solidify the wastes. Through a literature survey, DuraLith alkali-aluminosilicate geopolymer, fluidized-bed steam reformation (FBSR) granular product encapsulated in a geopolymer matrix, and a Ceramicrete phosphate-bonded ceramic were identified both as candidate waste forms and alternatives to the baseline.more » These waste forms have been shown to meet waste disposal acceptance criteria, including compressive strength and universal treatment standards for Resource Conservation and Recovery Act (RCRA) metals (as measured by the toxicity characteristic leaching procedure [TCLP]). Thus, these non-cementitious waste forms should also be acceptable for land disposal. Information is needed on all four waste forms with respect to their capability to minimize the release of technetium. Technetium is a radionuclide predicted to be in the secondary liquid wastes in small quantities, but the Integrated Disposal Facility (IDF) risk assessment analyses show that technetium, even at low mass, produces the largest contribution to the estimated IDF disposal impacts to groundwater.« 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

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

Design and fabrication of metal briquette machine for shop floor

NASA Astrophysics Data System (ADS)

Pramod, R.; Kumar, G. B. Veeresh; Prashanth B., N.

2017-07-01

Efforts have to be taken to ensure efficient waste management system in shop floors, with minimum utilization of space and energy when it comes to disposing metal chips formed during machining processes. The salvaging of junk metallic chips and the us e of scrap are important for the economic production of a steelworks. For this purpose, we have fabricated a metal chip compaction machine, which can compact the metal chips into small briquettes. The project started with the survey of chips formed in shop floors and the practices involved in waste management. Study was done on the requirements for a better compaction. The heating chamber was designed taking into consideration the temperature required for an easy compaction of the metal chips. The power source for compaction and the pneumatic design for mechanism was done following the appropriate calculations regarding the air pressure provided and thrust required. The processes were tested under different conditions and found effective. The fabrication of the machine has been explained in detail and the results have been discussed.

Dissolution Behaviour of Metal Elements from Several Types of E-waste Using Leaching Test

NASA Astrophysics Data System (ADS)

Nor, Nik Hisyamudin Muhd; Amira Nordin, Nurul; Mohamad, Fariza; Jaibee, Shafizan; Ismail, Al Emran; Omar, Badrul; Fauzi Ahmad, Mohd; Rahim, Abd Khalil Abd; Kamaruddin, Muhamad Khalif Ikhwan Mohd; Turan, Faiz Mohd; Abu Bakar, Elmi; Yokoyama, Seiji

2017-08-01

Rapid development of the electrical and electronic was increasing annually due to the demand by the human being. Increasing production of electrical and electronic product led to the increasing of electric and electronic waste or can be called as the e-waste. The UN Environment Programme estimates that the world generates 20-50 million tons of the e-waste each year and the amount is raising three times faster than other forms of municipal waste. This study is focusing on the investigation of the dissolution behaviour of metal element from several types of e-waste by hydrometallurgical process. Leaching test was conducted on the e-waste by using acid as the reagent solution. Prior to the leaching test, manual dismantling, separation, and crushing process were carried out to the e-waste. The e-waste were characterized by Scanning Electron Microcopy (SEM) and the Energy Dispersive X-ray Spectroscopy (EDX) to define the elements inside the sample of e-waste. While the liquid residue from leaching test was analyzed by using Inductively Couple Plasma-Mass Spectrometer (ICP-MS) to define the dissolution behaviour of the metal element that contain in the e-waste. It was found that the longest time for dismantling process was the dismantling of laptop. The dissolution behaviour of Fe, Al, Zn and Pb elements in the e-waste has affected to the increase of pH. The increasing pH led to the reduction of the metals element during leaching process.

ACID-BASE ACCOUNT EFFECTIVENESS FOR DETERMINATION OF MINE WASTE POTENTIAL ACIDITY. (R825549C048)

EPA Science Inventory

The oxidation of sulfide minerals in mine waste is a widespread source of resource degradation, often resulting in the generation of acidic water and mobilization of heavy metals. The quantity of acid forming minerals present in mine waste, dominantly as pyrite (FeS₂

Variation and distribution of metals and metalloids in soil/ash mixtures from Agbogbloshie e-waste recycling site in Accra, Ghana.

PubMed

Itai, Takaaki; Otsuka, Masanari; Asante, Kwadwo Ansong; Muto, Mamoru; Opoku-Ankomah, Yaw; Ansa-Asare, Osmund Duodu; Tanabe, Shinsuke

2014-02-01

Illegal import and improper recycling of electronic waste (e-waste) are an environmental issue in developing countries around the world. African countries are no exception to this problem and the Agbogbloshie market in Accra, Ghana is a well-known e-waste recycling site. We have studied the levels of metal(loid)s in the mixtures of residual ash, formed by the burning of e-waste, and the cover soil, obtained using a portable X-ray fluorescence spectrometer (P-XRF) coupled with determination of the 1M HCl-extractable fraction by an inductively coupled plasma mass spectrometer. The accuracy and precision of the P-XRF measurements were evaluated by measuring 18 standard reference materials; this indicated the acceptable but limited quality of this method as a screening tool. The HCl-extractable levels of Al, Co, Cu, Zn, Cd, In, Sb, Ba, and Pb in 10 soil/ash mixtures varied by more than one order of magnitude. The levels of these metal(loid)s were found to be correlated with the color (i.e., soil/ash ratio), suggesting that they are being released from disposed e-waste via open burning. The source of rare elements could be constrained using correlation to the predominant metals. Human hazard quotient values based on ingestion of soil/ash mixtures exceeded unity for Pb, As, Sb, and Cu in a high-exposure scenario. This study showed that along with common metals, rare metal(loid)s are also enriched in the e-waste burning site. We suggest that risk assessment considering exposure to multiple metal(loid)s should be addressed in studies of e-waste recycling sites. © 2013. Published by Elsevier B.V. All rights reserved.

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

NASA Astrophysics Data System (ADS)

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

2017-10-01

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

ENGINEERING BULLETIN: IN SITU VITRIFICATION TREATMENT

EPA Science Inventory

In situ vitrification (ISV) uses electrical power to heat and melt soil, sludge, mine tailings, buried wastes, and sediments contaminated with organic, inorganic, and metal-bearing hazardous wastes. The molten material cools to form a hard, monolithic, chemically inert, stable...

Changes in metal speciation and pH in olive processing waste and sulphur-treated contaminated soil.

PubMed

de la Fuente, C; Clemente, R; Bernal, M P

2008-06-01

Degradation of organic matter from olive mill waste and changes in the heavy metal fractionation of a metal-contaminated calcareous soil were studied in a laboratory experiment, in which the olive mill waste was mixed with the soil and then incubated under aerobic conditions. The soil was calcareous (15% CaCO(3)) with high Zn and Pb concentrations (2058 and 2947 mg kg(-1), respectively). The organic amendment was applied at a rate equivalent to 20 g kg(-1) soil, and unamended soil was run as a control. To discern if changes in metal solubility were due to the acidic character of the waste, elemental sulphur was applied to soil as a non-organic acidifying material. The S(0) rates used were 3.14, 4.71 and 6.28 g kg(-1). The mineralisation of total organic-C (TOC) from the waste reached 14.8% of the original TOC concentration after 56 days of incubation. The CO(2)-C produced from S(0)-treated soils showed the carbonate destruction by the H(2)SO(4) formed through S(0) oxidation. The organic waste increased EDTA-extractable Zn and Pb concentrations and CaCl(2)-extractable Mn levels in soil after two days of incubation. The changes in metal availability with time indicated that the oxidation of phenols from the waste reduced Mn (IV) oxides, releasing Zn and Pb associated with this mineral phase. Organic waste addition did not decrease soil pH; the acidifying effect of S(0) did not change metal fractionation in the soil.

THERMAL ENCAPSULATION OF METALS IN SUPERFUND SOILS

EPA Science Inventory

Superfund sites frequently contain both heavy metals and organic hazardous waste. If not properly controlled, the metals may be changed to a more leachable form and may also be emitted to the atmosphere via the exhaust stack. This paper documents a batch kiln R&D test program to ...

Distribution of copper, silver and gold during thermal treatment with brominated flame retardants.

PubMed

Oleszek, Sylwia; Grabda, Mariusz; Shibata, Etsuro; Nakamura, Takashi

2013-09-01

The growing consumption of electric and electronic equipment results in creating an increasing amount of electronic waste. The most economically and environmentally advantageous methods for the treatment and recycling of waste electric and electronic equipment (WEEE) are the thermal techniques such as direct combustion, co-combustion with plastic wastes, pyrolysis and gasification. Nowadays, this kind of waste is mainly thermally treated in incinerators (e.g. rotary kilns) to decompose the plastics present, and to concentrate metals in bottom ash. The concentrated metals (e.g. copper, precious metals) can be supplied as a secondary raw material to metal smelters, while the pyrolysis of plastics allows the recovery of fuel gases, volatilising agents and, eventually, energy. Indeed, WEEE, such as a printed circuit boards (PCBs) usually contains brominated flame retardants (BFRs). From these materials, hydrobromic acid (HBr) is formed as a product of their thermal decomposition. In the present work, the bromination was studied of copper, silver and gold by HBr, originating from BFRs, such as Tetrabromobisphenol A (TBBPA) and Tetrabromobisphenol A-Tetrabromobisophenol A diglycidyl ether (TTDE) polymer; possible volatilization of the bromides formed was monitored using a thermo-gravimetric analyzer (TGA) and a laboratory-scale furnace for treating samples of metals and BFRs under an inert atmosphere and at a wide range of temperatures. The results obtained indicate that up to about 50% of copper and silver can evolve from sample residues in the form of volatile CuBr and AgBr above 600 and 1000°C, respectively. The reactions occur in the molten resin phase simultaneously with the decomposition of the brominated resin. Gold is resistant to HBr and remains unchanged in the residue. Copyright © 2013 Elsevier Ltd. All rights reserved.

Transboundary hazardous waste management. Part I: Waste management policy of importing countries.

PubMed

Fan, Kuo-Shuh; Chang, Tien Chin; Ni, Shih-Piao; Lee, Ching-Hwa

2005-12-01

Mixed metal-containing waste, polychlorinated biphenyls (PCB) containing capacitors, printed circuit boards, steel mill dust and metal sludge were among the most common wastes exported from Taiwan. Before the implementation of the self-monitoring model programme of the Basel Convention (secretariat of the Basel Convention 2001) in the Asia region, Taiwan conducted a comprehensive 4-year follow-up project involving government authorities and the waste disposal facilities of the importing countries. A total of five countries and nine plants were visited in 2001-2002. The following outcomes can be drawn from these investigations. The Chinese government adopts the strategies of 'on-site processing' and 'relative centralization' on the waste management by tightening permitting and increasing site inspection. A three-level reviewing system is adopted for the import application. The United States have not signed the Basel Convention yet; the procedures of hazardous waste import rely on bilateral agreements. Importers are not required to provide official notification from the waste exporting countries. The operation, administration, monitoring and licensing of waste treatment plants are governed by the state environmental bureau. Finland, France and Belgium are members of the European Union. The procedures and policies of waste import are similar. All of the documents associated with transboundary movement require the approval of each government involved. Practically, the notification forms and tracking forms effectively manage the waste movement.

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

NASA Astrophysics Data System (ADS)

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

2013-07-01

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

Formation of chemically bonded ceramics with magnesium dihydrogen phosphate binder

DOEpatents

Wagh, Arun S.; Jeong, Seung-Young

2004-08-17

A new method for combining magnesium oxide, MgO, and magnesium dihydrogen phosphate to form an inexpensive compactible ceramic to stabilize very low solubility metal oxides, ashes, swarfs, and other iron or metal-based additives, to create products and waste forms which can be poured or dye cast, and to reinforce and strengthen the ceramics formed by the addition of fibers to the initial ceramic mixture.

Destruction of Navy Hazardous Wastes by Supercritical Water Oxidation

DTIC Science & Technology

1994-08-01

cleaning and derusting (nitrite and citric acid solutions), electroplating ( acids and metal bearing solutions), electronics and refrigeration... acid forming chemical species or that contain a large amount of dissolved solids present a challenge to current SCWO •-chnology. Approved for public...Waste streams that contain a large amount of mineral- acid forming chemical species or that contain a large amount of dissolved solids present a challenge

Formation and corrosion of a 410 SS/ceramic composite

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

Chen, X.; Ebert, W. L.; Indacochea, J. E.

This study evaluates the possible use of alloy/ceramic composite waste forms to immobilize metallic and oxide waste streams generated during the electrochemical reprocessing of spent reactor fuel in a single waste form. A representative composite material AOC410 was made to evaluate the microstructure and corrosion behavior at alloy/ceramic interfaces by reacting 410 stainless steel with Zr, Mo, and a mixture of lanthanide oxides. Essentially all of the Zr reacted with lanthanide oxides to form lanthanide zirconate, which combined with the remaining lanthanide oxides to form a porous ceramic network encapsulated by alloy as a composite puck. Excess alloy formed amore » metal bead on top of the composite. The alloys in the composite and bead were both mixture of martensite grains and ferrite grains with carbide precipitates. FeCrMo intermetallic phases also precipitated in the ferrite grains in the composite part. Ferrite surrounding carbides was sensitized and the least corrosion resistant in electrochemical corrosion tests conducted in an acidic brine electrolyte; ferrite neighboring martensite grains and intermetallics corroded galvanically. The lanthanide oxide domains dissolved chemically, but lanthanide zirconate domains did not dissolve. The presence of oxide phases did not affect corrosion of the neighboring alloy phases. These results suggest the longterm corrosion of a composite waste form can be evaluated by using separate material degradation models for the alloy and ceramic phases.« less

Recovery of fissile materials from nuclear wastes

DOEpatents

Forsberg, Charles W.

1999-01-01

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

Characterization of the non-metal fraction of the processed waste printed circuit boards.

PubMed

Kumar, Amit; Holuszko, Maria E; Janke, Travis

2018-05-01

Electronic waste is one the fastest growing waste streams in the world and waste printed circuit boards (PCB) are the most valuable part of this stream due to the presence of gold, silver, copper, and palladium. The metal present in PCBs is mostly recovered for the market value whereas the nonmetal fractions are often ignored. This research explored the characteristics of the non-metal fraction (NMF) obtained after the processing of milled waste PCBs with a focus on responsible end-of-life solutions, in the form of non-hazardous landfilling or incineration. The NMF was characterized using sizing, assaying, loss on ignition, calorific value measurement, and thermogravimetric analysis (TGA). The result showed that the metal content in the NMF increased with decrease in the particle size for most of the metals except antimony and the result from loss on ignition (LOI) also showed that over 50% of the coarser fraction represented organic matter compared to less than 30% for the finest fraction. The study also showed that after the recovery of metals from the waste PCBs, landfill leaching for most of the metal is reduced below the environmental limits, with lead being the only exception. The lead leachate concentration of 18 mg/L was observed, which requires further treatment prior to landfilling. With an energy value of 16 GJ/t, the NMF could provide high energy recovery if incinerated but 194 mg/kg of hazardous flame retardants present in the NMF might be released if the combustion process is not closely monitored. Copyright © 2018 Elsevier Ltd. All rights reserved.

Interim waste storage for the Integral Fast Reactor

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

Benedict, R.W.; Phipps, R.D.; Condiff, D.W.

1991-01-01

The Integral Fast Reactor (IFR), which Argonne National Laboratory is developing, is an innovative liquid metal breeder reactor that uses metallic fuel and has a close coupled fuel recovery process. A pyrochemical process is used to separate the fission products from the actinide elements. These actinides are used to make new fuel for the reactor. As part of the overall IFR development program, Argonne has refurbished an existing Fuel Cycle Facility at ANL-West and is installing new equipment to demonstrate the remote reprocessing and fabrication of fuel for the Experimental Breeder Reactor II (EBR-II). During this demonstration the wastes thatmore » are produced will be treated and packaged to produce waste forms that would be typical of future commercial operations. These future waste forms would, assuming Argonne development goals are fulfilled, be essentially free of long half-life transuranic isotopes. Promising early results indicate that actinide extraction processes can be developed to strip these isotopes from waste stream and return them to the IFR type reactors for fissioning. 1 fig.« less

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

Treatment of electronic waste to recover metal values using thermal plasma coupled with acid leaching - A response surface modeling approach

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

Rath, Swagat S., E-mail: swagat.rath@gmail.com; Nayak, Pradeep; Mukherjee, P.S.

2012-03-15

Highlights: Black-Right-Pointing-Pointer Sentences/phrases were modified. Black-Right-Pointing-Pointer Necessary discussions for different figures were included. Black-Right-Pointing-Pointer More discussion have been included on the flue gas analysis. Black-Right-Pointing-Pointer Queries to both the reviewers have been given. - Abstract: The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values asmore » a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency.« less

Development of iron phosphate ceramic waste form to immobilize radioactive waste solution

NASA Astrophysics Data System (ADS)

Choi, Jongkwon; Um, Wooyong; Choung, Sungwook

2014-09-01

The objective of this research was to develop an iron phosphate ceramic (IPC) waste form using converter slag obtained as a by-product of the steel industry as a source of iron instead of conventional iron oxide. Both synthetic off-gas scrubber solution containing technetium-99 (or Re as a surrogate) and LiCl-KCl eutectic salt, a final waste solution from pyrochemical processing of spent nuclear fuel, were used as radioactive waste streams. The IPC waste form was characterized for compressive strength, reduction capacity, chemical durability, and contaminant leachability. Compressive strengths of the IPC waste form prepared with different types of waste solutions were 16 MPa and 19 MPa for LiCl-KCl eutectic salt and the off-gas scrubber simulant, respectively, which meet the minimum compressive strength of 3.45 MPa (500 psi) for waste forms to be accepted into the radioactive waste repository. The reduction capacity of converter slag, a main dry ingredient used to prepare the IPC waste form, was 4136 meq/kg by the Ce(IV) method, which is much higher than those of the conventional Fe oxides used for the IPC waste form and the blast furnace slag materials. Average leachability indexes of Tc, Li, and K for the IPC waste form were higher than 6.0, and the IPC waste form demonstrated stable durability even after 63-day leaching. In addition, the Toxicity Characteristic Leach Procedure measurements of converter slag and the IPC waste form with LiCl-KCl eutectic salt met the universal treatment standard of the leachability limit for metals regulated by the Resource Conservation and Recovery Act. This study confirms the possibility of development of the IPC waste form using converter slag, showing its immobilization capability for radionuclides in both LiCl-KCl eutectic salt and off-gas scrubber solutions with significant cost savings.

Development of iron phosphate ceramic waste form to immobilize radioactive waste solution

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

Choi, Jongkwon; Um, Wooyong; Choung, Sungwook

The objective of this research was to develop an iron phosphate ceramic (IPC) waste form using converter slag obtained as a by-product of the steel industry as a source of iron instead of conventional iron oxide. Both synthetic off-gas scrubber solution containing technetium-99 (or Re as a surrogate) and LiCl-KCl eutectic salt, a final waste solution from pyrochemical processing of spent nuclear fuel, were used as radioactive waste streams. The IPC waste form was characterized for compressive strength, reduction capacity, chemical durability, and contaminant leachability. Compressive strengths of the IPC waste form prepared with different types of waste solutions weremore » 16 MPa and 19 MPa for LiCl-KCl eutectic salt and the off-gas scrubber simulant, respectively, which meet the minimum compressive strength of 3.45 MPa (500 psi) for waste forms to be accepted into the radioactive waste repository. The reduction capacity of converter slag, a main dry ingredient used to prepare the IPC waste form, was 4,136 meq/kg by the Ce(IV) method, which is much higher than those of the conventional Fe oxides used for the IPC waste form and the blast furnace slag materials. Average leachability indexes of Tc, Li, and K for the IPC waste form were higher than 6.0, and the IPC waste form demonstrated stable durability even after 63-day leaching. In addition, the Toxicity Characteristic Leach Procedure measurements of converter slag and the IPC waste form with LiCl-KCl eutectic salt met the universal treatment standard of the leachability limit for metals regulated by the Resource Conservation and Recovery Act. This study confirms the possibility of development of the IPC waste form using converter slag, showing its immobilization capability for radionuclides in both LiCl-KCl eutectic salt and off-gas scrubber solutions with significant cost savings.« less

Recovery of metals from simulant spent lithium-ion battery as organophosphonate coordination polymers in aqueous media.

PubMed

Perez, Emilie; Andre, Marie-Laure; Navarro Amador, Ricardo; Hyvrard, François; Borrini, Julien; Carboni, Michaël; Meyer, Daniel

2016-11-05

An innovative approach is proposed for the recycling of metals from a simulant lithium-ion battery (LIBs) waste aqueous solution. Phosphonate organic linkers are introduced as precipitating agents to selectively react with the metals to form coordination polymers from an aqueous solution containing Ni, Mn and Co in a hydrothermal process. The supernatant is analyzed by ICP-AES to quantify the efficiency and the selectivity of the precipitation and the materials are characterized by Scanning Electron Microscopy (SEM), Powder X-Ray Diffraction (PXRD), Thermogravimetric Analyses (TGA) and nitrogen gas sorption (BET). Conditions have been achieved to selectively precipitate Manganese or Manganese/Cobalt from this solution with a high efficiency. This work describes a novel method to obtain potentially valuable coordination polymers from a waste metal solution that can be generalized on any waste solution. Copyright © 2016 Elsevier B.V. All rights reserved.

Process for continuous production of metallic uranium and uranium alloys

DOEpatents

Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

1995-06-06

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

Process for continuous production of metallic uranium and uranium alloys

DOEpatents

Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.

1995-01-01

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

Risks of using EDTA as an agent for trace metals dosing in anaerobic digestion of olive mill solid waste.

PubMed

Serrano, A; Pinto-Ibieta, F; Braga, A F M; Jeison, D; Borja, R; Fermoso, F G

2017-12-01

Low concentrations of trace elements in many organic wastes recommend their supplementation in order to avoid potential limitations. Different chelating agents have been used to ensure an adequate trace metal pool in the soluble fraction, by forming dissolved complexes. Ethylenediaminetetraacetic acid (EDTA) is probably the most common, although several negative effects could be associated with its usage. Biomethane potential tests were performed using Olive Mill Solid Waste as the substrate, supplementing different combinations of Fe, Co, Ni, Ba, always under the presence of EDTA. Results show that Ni and Co slightly recovered biodegradability. However, Ba supplementation resulted in worsening the methane yield coefficient in all cases. High concentration of EDTA led to decrease in the activity of anaerobic digestion. High availability of EDTA induces the capture of trace metals like Co or Ni, key trace metals for anaerobic biomass activity. While supplementing trace metals, the addition of Ba and/or EDTA must be carefully considered.

Immobilization of radioactive and hazardous wastes in a developed sulfur polymer cement (SPC) matrix

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

Wagdy, M.; Azim, Abdel; El-Gammal, Belal

Available in abstract form only. Full text of publication follows: A process has been developed for the immobilization Cs, Sr, Ce, Pb, and Cr in forms that is non-dispersible and could be safely immobilized. The simulated radioactive wastes of Cs, Sr, and Ce, and the hazardous wastes of Cr, and Pb were immobilized in the stable form of sulfur polymer cement (SPC). In this process, the contaminants (in a single form) were added to the sulfur mixture of sulfur and aromatic /or aliphatic hydrocarbons that used as polymerizing agents for sulfur (95% S, and 5% organic polymer by weight). Durabilitymore » of the fabricated SPC matrices was assessed in terms of their water of immersion, porosity, and compressive strength. The water immersion, and open porosity were found to be less than 2.5% for all the prepared matrices, whereas the compressive strength was in the range between 62.4 and 142.3 Kg.cm{sup -2}, depending on the composition of the prepared matrix. The prepared SPC matrices that characterized by X-ray diffraction (XRD) showed that the different added contaminants were stabilized during the solidification process during their reaction with sulfur and the organic polymer to form the corresponding metal sulfides. Toxicity Characteristic Leaching Procedure (TCLP), and the IAEA standard method have assessed the leachability of the prepared waste matrices. The TCLP results showed that most the concentration of the contaminants released were under their detection limit. The leach index for the investigated metals from the prepared SPC matrices was in the range of 9-11. The order of release of the investigated metals was Sr>Cs>Pb>Cr>Ce for the aliphatic polymer, and Sr>Cr>Pb>Cs>Ce for the aromatic one. The results obtained revealed a high performance for the prepared SPC matrices, as they are of low cost effect, highly available materials, and possessed good mechanical and leaching properties. Key Words: SPC/ Matrices/ Immobilization/ Wastes/ Leachability. (authors)« less

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

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

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

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

[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.

Waste gas storage

NASA Technical Reports Server (NTRS)

Vickers, Brian D. (Inventor)

1994-01-01

Method for storing a waste gas mixture comprised of nitrogen, oxygen, carbon dioxide, and inert gases, the gas mixture containing corrosive contaminants including inorganic acids and bases and organic solvents, and derived from space station operations. The gas mixture is stored under pressure in a vessel formed of a filament wound composite overwrap on a metal liner, the metal liner being pre-stressed in compression by the overwrap, thereby avoiding any tensile stress in the liner, and preventing stress corrosion cracking of the liner during gas mixture storage.

Kinetic vaporization of heavy metals during fluidized bed thermal treatment of municipal solid waste.

PubMed

Yu, Jie; Sun, Lushi; Xiang, Jun; Hu, Song; Su, Sheng

2013-02-01

Heavy metals volatilization during thermal treatment of model solid waste was theoretically and experimentally investigated in a fluidized bed reactor. Lead, cadmium, zinc and copper, the most four conventional heavy metals were investigated. Particle temperature model and metal diffusion model were established to simulate the volatilization of CdCl(2) evaporation and investigate the possible influencing factors. The diffusion coefficient, porosity and particle size had significant effects on metal volatilization. The higher diffusion coefficient and porosity resulted in the higher metal evaporation. The influence of redox conditions, HCl, water and mineral matrice were also investigated experimentally. The metal volatilization can be promoted by the injection of HCl, while oxygen played a negative role. The diffusion process of heavy metals within particles also had a significant influence on kinetics of their vaporization. The interaction between heavy metals and mineral matter can decrease metal evaporation amount by forming stable metallic species. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biochemical solubilization of toxic salts from residual geothermal brines and waste waters

DOEpatents

Premuzic, Eugene T.; Lin, Mow S.

1994-11-22

A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed, The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts, For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates.

Mechanisms and modelling of waste-cement and cement-host rock interactions

NASA Astrophysics Data System (ADS)

2017-06-01

Safe and sustainable disposal of hazardous and radioactive waste is a major concern in today's industrial societies. The hazardous waste forms originate from residues of thermal treatment of waste, fossil fuel combustion and ferrous/non-ferrous metal smelting being the most important ones in terms of waste production. Low- and intermediate-level radioactive waste is produced in the course of nuclear applications in research and energy production. For both waste forms encapsulation in alkaline, cement-based matrices is considered to ensure long-term safe disposal. Cementitious materials are in routine use as industrial materials and have mainly been studied with respect to their evolution over a typical service life of several decades. Use of these materials in waste management applications, however, requires assessments of their performance over much longer time periods on the order of thousands to several ten thousands of years.

Reclamation of soils influenced by coal mining in Southern European Russia

NASA Astrophysics Data System (ADS)

Alekseenko, Vladimir; Bech, Jaume; Alekseenko, Alexey; Shvydkaya, Natalya; Roca, Núria

2016-04-01

In the recent decades, the concentrations of metals have increased in such media of biosphere as atmosphere, hydrosphere, pedosphere. The greatest geochemical changes have occurred in soils, which are the deposing medium where the high concentrations of metals are saved for years after their direct human use. Mining sites and beneficiation zones are the areas of the highest concentrations of metals in soils. Coal mining areas in the European part of Russia (Rostov region) were selected for a detailed consideration. Soil samples were taken from the uppermost soil horizons: layer of 0-30 cm. The soil samples were analysed for gross concentrations of Cu, Zn, Pb, Ag, Sn, Mo, Ba, Co, Ni, Mn, Ti, V, Cr, Ga, P, Li, Sr, Y, Yb, Nb, Sc, and Zr, using emission spectral analysis. All ordinary analyses were carried out in the certified and accredited laboratory. The external control was conducted by the X-ray fluorescence, gravimetric, and neutron activation analyses. Calculation of random and systematic errors showed high analyses repeatability and correctness. Several cases of self-purification of soils and restoration of landscapes were discussed. The way of remediation through the flooding of mining sites with water was investigated as well as filling of natural relief depressions with soils and dumps. The process of Technosols remediation at the sites occupied by tailings of waste heaps was considered separately. In conclusion: 1. The dominant contemporary way of remediation in Southern European Russia does not prevent the spread of metals through the decades. The modern underground coal mining leads to the destruction of soils in the area directly occupied by wastes and by rock dumps located nearby. 2. Soils have not formed yet as a result of self-restoration at the waste heaps at the age of 50 years, spontaneously combusted decades ago. The vegetation formed during this time virtually eliminates the occurrence of any significant soil-forming process. The ponds formed by the flooding of burning waste heaps, do not give possibility for the formation of soils and hardly contribute to plant growth. 3. The Technosols of waste heaps' surface layers are different from the surrounding steppe soils in geochemical features and mineralogical composition at every stage of their development. 4. The atmospheric and water inflow of material from the waste heaps changes (in the cases studied - worsens) the state of steppe soils within a radius of 1 km, and leads to the increase of heavy metals content in these soils. Keywords: Technosols, Technogenic Superficial Formations, self-purification, flooding

Converting untreated waste office paper and chitosan into aerogel adsorbent for the removal of heavy metal ions.

PubMed

Li, Zhanying; Shao, Lin; Ruan, Zehai; Hu, Wenbin; Lu, Lingbin; Chen, Yongjun

2018-08-01

The utilization of waste paper, an obsolete recyclable resource, helps to save resources and protect environment. In this paper, an aerogel was prepared to convert the waste paper into a useful material, which was used to adsorb heavy metal ions and handle water pollution. Combining waste office paper and chitosan, the aerogel obtained the enhanced mechanical strength, acid resistance and high adsorption capacity (up to 156.3 mg/g for Cu 2+ ). This adsorption process obeyed the pseudo-second order model and the Langmuir model. The research showed that a coordination compound was formed between amino group and Cu 2+ during the adsorption process. The adsorbent could be regenerated well in 0.1 M H 2 SO 4 with up to 98.3% desorption efficiency. The low cost, environmental friendliness, excellent adsorption capacity and regeneration ability made this novel aerogel a promising adsorbent for heavy metal ions. And this conversion is an effective reuse way of waste paper too. Copyright © 2018 Elsevier Ltd. All rights reserved.

Distribution of copper, silver and gold during thermal treatment with brominated flame retardants

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

Oleszek, Sylwia, E-mail: sylwia_oleszek@yahoo.com; Institute of Environmental Engineering of the Polish Academy of Sciences, 34 M. Sklodowska-Curie St., 41-819 Zabrze; Grabda, Mariusz, E-mail: mariusz@mail.tagen.tohoku.ac.jp

2013-09-15

Highlights: • Copper, silver and gold during thermal treatment with brominated flame retardants. • Distribution of copper, silver and gold during thermal processing. • Thermodynamic considerations of the bromination reactions. - Abstract: The growing consumption of electric and electronic equipment results in creating an increasing amount of electronic waste. The most economically and environmentally advantageous methods for the treatment and recycling of waste electric and electronic equipment (WEEE) are the thermal techniques such as direct combustion, co-combustion with plastic wastes, pyrolysis and gasification. Nowadays, this kind of waste is mainly thermally treated in incinerators (e.g. rotary kilns) to decompose themore » plastics present, and to concentrate metals in bottom ash. The concentrated metals (e.g. copper, precious metals) can be supplied as a secondary raw material to metal smelters, while the pyrolysis of plastics allows the recovery of fuel gases, volatilising agents and, eventually, energy. Indeed, WEEE, such as a printed circuit boards (PCBs) usually contains brominated flame retardants (BFRs). From these materials, hydrobromic acid (HBr) is formed as a product of their thermal decomposition. In the present work, the bromination was studied of copper, silver and gold by HBr, originating from BFRs, such as Tetrabromobisphenol A (TBBPA) and Tetrabromobisphenol A-Tetrabromobisophenol A diglycidyl ether (TTDE) polymer; possible volatilization of the bromides formed was monitored using a thermo-gravimetric analyzer (TGA) and a laboratory-scale furnace for treating samples of metals and BFRs under an inert atmosphere and at a wide range of temperatures. The results obtained indicate that up to about 50% of copper and silver can evolve from sample residues in the form of volatile CuBr and AgBr above 600 and 1000 °C, respectively. The reactions occur in the molten resin phase simultaneously with the decomposition of the brominated resin. Gold is resistant to HBr and remains unchanged in the residue.« less

Geochemical processes controlling the distribution and concentration of metals in soils from a Patagonian (Argentina) salt marsh affected by mining residues.

PubMed

Idaszkin, Yanina L; Alvarez, María Del Pilar; Carol, Eleonora

2017-10-15

Heavy metal pollution that affects salt marshes is a major environmental concern due to its toxic nature, persistence, and potential risk to organisms and to human health. Mining waste deposits originated four decades ago, by the metallurgical extraction of heavy metals, are found near to the San Antonio salt marsh in Patagonia. The aim of the work was to determine the geochemical processes that control the distribution and concentration of Cu, Fe, Pb and Zn in the soils of this Patagonian salt marsh. A survey of the mining waste deposits was carried out where three dumps were identified. Samples were collected to determine soil texture, Eh pH, organic matter and metal contents and the soil mineralogical composition. The results shows that the soils developed over the mining waste deposits are predominantly reddish constituted mainly by iron oxide, hydroxide and highly soluble minerals such as Zn and Cu sulphates. The drainage from these deposits tends to move towards the salt marsh. Within the salt marsh, the highest concentrations of Cu, Pb and Zn occur in the sectors closest to the mining wastes deposits. The sulphide oxidation and the dissolution of the Cu, Pb and Zn sulphates could be the mainly source of these metals in the drainage water. The metals in solution that reach the salt marsh, are adsorbed by the organic matter and the fine fraction of the soils. These adsorbed metals are then remobilized by tides in the lower sectors of the marsh by desorption from the cations present in the tidal flow. On the other hand, Fe tends to form non soluble oxides, hydroxides and sulphates which remain as altering material within the mining waste deposit. Finally, the heavy metal pollutants recorded in the San Antonio salt marsh shows that the mining waste deposits that were abandoned four decades ago are still a source metal contamination. Copyright © 2017 Elsevier B.V. All rights reserved.

In situ vitrification application to buried waste: Final report of intermediate field tests at Idaho National Engineering Laboratory

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

Callow, R.A.; Weidner, J.R.; Loehr, C.A.

This report describes two in situ vitrification field tests conducted on simulated buried waste pits during June and July 1990 at the Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to access the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National Engineering Laboratory. In particular, these tests, as part of a treatability study, were designedmore » to provide essential information on the field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste. Test results indicate the process is a feasible technology for application to buried waste. 33 refs., 109 figs., 39 tabs.« less

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

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

Delbert E. Ray; Chandra S. Ray

2013-11-01

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

Biochemical solubilization of toxic salts from residual geothermal brines and waste waters

DOEpatents

Premuzic, E.T.; Lin, M.S.

1994-11-22

A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed. The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts. For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates. 54 figs.

Radioactive waste material melter apparatus

DOEpatents

Newman, D.F.; Ross, W.A.

1990-04-24

An apparatus for preparing metallic radioactive waste material for storage is disclosed. The radioactive waste material is placed in a radiation shielded enclosure. The waste material is then melted with a plasma torch and cast into a plurality of successive horizontal layers in a mold to form a radioactive ingot in the shape of a spent nuclear fuel rod storage canister. The apparatus comprises a radiation shielded enclosure having an opening adapted for receiving a conventional transfer cask within which radioactive waste material is transferred to the apparatus. A plasma torch is mounted within the enclosure. A mold is also received within the enclosure for receiving the melted waste material and cooling it to form an ingot. The enclosure is preferably constructed in at least two parts to enable easy transport of the apparatus from one nuclear site to another. 8 figs.

Radioactive waste material melter apparatus

DOEpatents

Newman, Darrell F.; Ross, Wayne A.

1990-01-01

An apparatus for preparing metallic radioactive waste material for storage is disclosed. The radioactive waste material is placed in a radiation shielded enclosure. The waste material is then melted with a plasma torch and cast into a plurality of successive horizontal layers in a mold to form a radioactive ingot in the shape of a spent nuclear fuel rod storage canister. The apparatus comprises a radiation shielded enclosure having an opening adapted for receiving a conventional transfer cask within which radioactive waste material is transferred to the apparatus. A plasma torch is mounted within the enclosure. A mold is also received within the enclosure for receiving the melted waste material and cooling it to form an ingot. The enclosure is preferably constructed in at least two parts to enable easy transport of the apparatus from one nuclear site to another.

Formation and corrosion of a 410 SS/ceramic composite

NASA Astrophysics Data System (ADS)

Chen, X.; Ebert, W. L.; Indacochea, J. E.

2016-11-01

This study addressed the possible use of alloy/ceramic composite waste forms to immobilize metallic and oxide waste streams generated during the electrochemical reprocessing of spent reactor fuel using a single waste form. A representative composite material was made to evaluate the microstructure and corrosion behavior at alloy/ceramic interfaces by reacting 410 stainless steel with Zr, Mo, and a mixture of lanthanide oxides. Essentially all of the available Zr reacted with lanthanide oxides to generate lanthanide zirconates, which combined with the unreacted lanthanide oxides to form a porous ceramic network that filled with alloy to produce a composite puck. Alloy present in excess of the pore volume of the ceramic generated a metal bead on top of the puck. The alloys in the composite and forming the bead were both mixtures of martensite grains and ferrite grains bearing carbide precipitates; FeCrMo intermetallic phases also precipitated at ferrite grain boundaries within the composite puck. Micrometer-thick regions of ferrite surrounding the carbides were sensitized and corroded preferentially in electrochemical tests. The lanthanide oxides dissolved chemically, but the lanthanide zirconates did not dissolve and are suitable host phases. The presence of oxide phases did not affect corrosion of the neighboring alloy phases.

Self-Healing Capacity of Asphalt Mixtures Including By-Products Both as Aggregates and Heating Inductors.

PubMed

Vila-Cortavitarte, Marta; Jato-Espino, Daniel; Castro-Fresno, Daniel; Calzada-Pérez, Miguel Á

2018-05-15

Major advances have been achieved in the field of self-healing by magnetic induction in which the addition of metallic particles into asphalt mixtures enables repairing their own cracks. This technology has already been proven to increase the life expectancy of roads. Nevertheless, its higher costs in comparison with conventional maintenance caused by the price of virgin metallic particles still makes it unattractive for investment. This research aimed at making this process economically accessible as well as environmentally efficient. To this end, an intense search for suitable industrial by-products to substitute both the virgin metal particles and the natural aggregates forming asphalt mixtures was conducted. The set of by-products used included sand blasting wastes, stainless shot wastes, and polished wastes as metallic particles and other inert by-products as aggregates. The results demonstrated that the by-products were adequately heated, which leads to satisfactory healing ratios in comparison with the reference mixture.

Self-Healing Capacity of Asphalt Mixtures Including By-Products Both as Aggregates and Heating Inductors

PubMed Central

Castro-Fresno, Daniel; Calzada-Pérez, Miguel Á.

2018-01-01

Major advances have been achieved in the field of self-healing by magnetic induction in which the addition of metallic particles into asphalt mixtures enables repairing their own cracks. This technology has already been proven to increase the life expectancy of roads. Nevertheless, its higher costs in comparison with conventional maintenance caused by the price of virgin metallic particles still makes it unattractive for investment. This research aimed at making this process economically accessible as well as environmentally efficient. To this end, an intense search for suitable industrial by-products to substitute both the virgin metal particles and the natural aggregates forming asphalt mixtures was conducted. The set of by-products used included sand blasting wastes, stainless shot wastes, and polished wastes as metallic particles and other inert by-products as aggregates. The results demonstrated that the by-products were adequately heated, which leads to satisfactory healing ratios in comparison with the reference mixture. PMID:29762533

I-NERI Annual Technical Progress Report 2007-004-K Development and Characterization of New High-Level Waste Forms for Achieving Waste Minimization from Pyroprocessing

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

S. Frank

The current method for the immobilization of fission products that accumulate in electrorefiner salt during the electrochemical processing of used metallic nuclear fuel is to encapsulate the electrorefiner salt in a glass-bonded sodalite ceramic waste form. This process was developed by Argonne National Laboratory in the USA and is currently performed at the Idaho National Laboratory for the treatment of Experimental Breeder Reactor-II (EBR-II) used fuel. This process utilizes a “once-through” option for the disposal of spent electrorefiner salt; where, after the treatment of the EBR-II fuel, the electrorefiner salt containing the active fission products will be disposed of inmore » the ceramic waste form (CWF). The CWF produced will have low fission product loading of approximately 2 to 5 weight percent due to the limited fuel inventory currently being processed. However; the design and implementation of advanced electrochemical processing facilities to treat used fuel would process much greater quantities fuel. With an advanced processing facility, it would be necessary to selectively remove fission products from the electrorefiner salt for salt recycle and to concentrate the fission products to reduce the volume of high-level waste from the treatment facility. The Korean Atomic Energy Research Institute and the Idaho National Laboratory have been collaborating on I-NERI research projects for a number of years to investigate both aspects of selective fission product separation from electrorefiner salt, and to develop advanced waste forms for the immobilization of the collected fission products. The first joint KAERI/INL I-NERI project titled: 2006-002-K, Separation of Fission Products from Molten LiCl-KCl Salt Used for Electrorefining of Metal Fuels, was successfully completed in 2009 by concentrating and isolating fission products from actual electrorefiner salt used for the treated used EBR-II fuel. Two separation methods were tested and from these tests were produced concentrated salt products that acted as the feed material for development of advanced waste forms investigated in this proposal. Accomplishments from the first year activities associated with this I-NERI project included the down selection of candidate waste forms to immobilize fission products separated from electrorefiner salt, and the design of equipment to fabricate actual waste forms in the Hot Fuels Examination Facility (HFEF) at the INL. Reported in this document are accomplishments from the second year (FY10) work performed at the INL, and includes the testing of waste form fabrication equipment, repeating the fission product precipitation experiment, and initial waste form fabrication efforts.« less

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 Ceramicrete binder is formed through an acid-base reaction between calcined magnesium oxide (MgO; a base) and potassium hydrogen phosphate (KH{sub 2}PO{sub 4}; an acid) in aqueous solution. The reaction product sets at room temperature to form a highly crystalline material. During the reaction, the hazardous and radioactive contaminants also react with KH{sub 2}PO{sub 4} to form highly insoluble phosphates. In this data package, physical property and waste acceptance data for Ceramicrete waste forms fabricated with wastes having compositions that were similar to those expected for secondary waste effluents, as well as secondary waste effluent simulants from the Hanford Tank Waste Treatment and Immobilization Plant were reviewed. With the exception of one secondary waste form formulation (25FA+25 W+1B.A. fabricated with the mixed simulant did not meet the compressive strength requirement), all the Ceramicrete waste forms that were reviewed met or exceeded Integrated Disposal Facility waste acceptance criteria.« less

Fractionation of Pb and Cu in the fine fraction (<10 mm) of waste excavated from a municipal landfill.

PubMed

Kaczala, Fabio; Orupõld, Kaja; Augustsson, Anna; Burlakovs, Juris; Hogland, Marika; Bhatnagar, Amit; Hogland, William

2017-11-01

The fractionation of metals in the fine fraction (<10 mm) of excavated waste from an Estonian landfill was carried out to evaluate the metal (Pb and Cu) contents and their potential towards not only mobility but also possibilities of recovery/extraction. The fractionation followed the BCR (Community Bureau of Reference) sequential extraction, and the exchangeable (F1), reducible (F2), oxidizable (F3) and residual fractions were determined. The results showed that Pb was highly associated with the reducible (F2) and oxidizable (F3) fractions, suggesting the potential mobility of this metal mainly when in contact with oxygen, despite the low association with the exchangeable fraction (F1). Cu has also shown the potential for mobility when in contact with oxygen, since high associations with the oxidizable fraction (F3) were observed. On the other hand, the mobility of metals in excavated waste can be seen as beneficial considering the circular economy and recovery of such valuables back into the economy. To conclude, not only the total concentration of metals but also a better understanding of fractionation and in which form metals are bound is very important to bring information on how to manage the fine fraction from excavated waste both in terms of environmental impacts and also recovery of such valuables in the economy.

Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana.

PubMed

Kyere, Vincent Nartey; Greve, Klaus; Atiemo, Sampson Manukure; Ephraim, James

2017-01-01

The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn). Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area.

Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana

PubMed Central

Greve, Klaus; Atiemo, Sampson Manukure

2017-01-01

The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb) and zinc (Zn). Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area. PMID:29056034

New Metal Niobate and Silicotitanate Ion Exchangers: Development and Characterization

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

Alexandra Navrotsky; Mary Lou Balmer; Tina M. Nenoff

2003-12-05

This renewal proposal outlines our current progress and future research plans for ion exchangers: novel metal niobate and silicotitanate ion exchangers and their ultimate deployment in the DOE complex. In our original study several forms (including Cs exchanged) of the heat treated Crystalline Silicotitanates (CSTs) were fully characterized by a combination of high temperature synthesis and phase identification, low temperature synthesis and phase identification, and thermodynamics. This renewal proposal is predicated on work completed in our current EMSP program: we have shown preliminary data of a novel class of niobate-based molecular sieves (Na/Nb/M/O, M = transition metals), which show exceptionallymore » high selectivity for divalent cations under extreme conditions (acid solutions, competing cations), in addition to novel silicotitanate phases which are also selective for divalent cations. Furthermore, these materials are easily converted by a high temperature in-situ heat treatment into a refractory ceramic waste form with low cation leachability. The new waste form is a perovskite phase, which is also a major component of Synroc, a titanate ceramic waste form used for sequestration of HLW wastes from reprocessed, spent nuclear fuel. These new niobate ion exchangers also shown orders of magnitude better selectivity for Sr2+ under acid conditions than any other material. The goal of the program is to reduce the costs associated with divalent cation waste removal and disposal, to minimize the risk of contamination to the environment during ion exchanger processing, and to provide DOE with materials for near-term lab-bench stimulant testing, and eventual deployment. The proposed work will provide information on the structure/property relationship between ion exchanger frameworks and selectivity for specific ions, allowing for the eventual ''tuning'' of framework for specific ion exchange needs. To date, DOE sites have become interested in on-site testing of these materials; ongoing discussions and initial experiments are occurring with Dr. Dean Peterman, Idaho National Engineering and Environmental Laboratory (INEEL) (location of the DOE/EM Waste Treatment Focus Area), and Dr. John Harbour, Savannah River Site (SRS). Yet the materials have not been optimized, and further research and development of the novel ion exchangers and testing conditions with simulants are needed. In addition, studies of the ion exchanger composition versus ion selectivity, ion exchange capacity and durability of final waste form are needed. This program will bring together three key institutions to address scientific hurdles of the separation process associated with metal niobate and silicotitanate ion exchangers, in particular for divalent cations (e.g., Sr2+). The program involves a joint effort between researchers at Pacific Northwest National Laboratory, who are leaders in structure/property relations in silicotitanates and in waste form development and performance assessment, Sandia National Laboratories, who discovered and developed crystalline silicotitanate ion exchangers (with Texas A&M and UOP) and also the novel class of divalent metal niobate ion exchangers, and the Thermochemistry Facility at UC Davis, who are world renowned experts in calorimetry and have already performed extensive thermodynamic studies on silicotitanate materials. In addition, Dr. Rodney Ewing of University of Michigan, an expert in radiation effects on materials, and Dr. Robert Roth of the National Institute of Standards and Technology and The Viper Group, a leader in phase equilibria development, will be consultants for radiation and phase studies. The research team will focus on three tasks that will provide both the basic research necessary for the development of highly selective ion exchange materials and also materials for short-term deployment within the DOE complex: (1) Structure/property relationships of a novel class of niobate-based molecular sieves (Na/Nb/M/O, M = transition metals), which show exceptionally high selectivity for divalent cations under extreme conditions (acid solutions, competing cations), (2) the role of ion exchanger structure change (both niobates and silicotitanates) on the exchange capacity (for elements such as Sr and actinide-surrogates) which results from exposure to DOE complex waste simulants, (3) thermodynamic stability of metal niobates and silicotitanate ion exchangers.« less

Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

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

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-06-08

Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Testsmore » were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal corrosion rates in water alone and in simulated sludge were near or slightly below the metal-in-water rate while nitrate-free sludge/Aquaset II decreased rates by about a factor of 3. Addition of 1 M nitrate to simulated sludge decreased the corrosion rate by a factor of ~5 while 1 M nitrate in sludge/Aquaset II mixtures decreased the corrosion rate by ~2.5 compared with the nitrate-free analogues. Mixtures of simulated sludge with Aquaset II treated with 1 M nitrate had uranium corrosion rates about a factor of 8 to 10 lower than the water-only rate law. Nitrate was found to provide substantial hydrogen mitigation for immobilized simulant sludge waste forms containing Aquaset II or Aquaset II G clay. Hydrogen attenuation factors of 1000 or greater were determined at 60°C for sludge-clay mixtures at 1 M nitrate. Hydrogen mitigation for tests with PC and Aquaset II H (which contains PC) were inconclusive because of suspected failure to overcome induction times and fully enter into anoxic corrosion. Lessening of hydrogen attenuation at ~80°C and ~95°C for simulated sludge and Aquaset II was observed with attenuation factors around 100 to 200 at 1 M nitrate. Valuable additional information has been obtained on the ability of nitrate to attenuate hydrogen gas generation from solution, simulant K Basin sludge, and simulant sludge with immobilization agents. Details on characteristics of the associated reactions were also obtained. The present testing confirms prior work which indicates that nitrate is an effective agent to attenuate hydrogen from uranium metal corrosion in water and simulated K Basin sludge to show that it is also effective in potential candidate solidified K Basin waste forms for WIPP disposal. The hydrogen mitigation afforded by nitrate appears to be sufficient to meet the hydrogen generation limits for shipping various sludge waste streams based on uranium metal concentrations and assumed waste form loadings.« less

The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions

DOE PAGES

Kolman, David Gary; Goff, George Scott; Cisneros, Michael Ruben; ...

2017-04-19

Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc +7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate ismore » relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc +4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.« less

The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions

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

Kolman, David Gary; Goff, George Scott; Cisneros, Michael Ruben

Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc +7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate ismore » relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc +4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.« less

Automation of NDE on RSRM Metal Components

NASA Technical Reports Server (NTRS)

Hartman, John; Kirby, Mark; McCool, Alex (Technical Monitor)

2002-01-01

An automated eddy current system has been designed and built, and is being implemented to inspect RSRM (Space Shuttle) metal components. The system provides a significant increase in inspection reliability, as well as other benefits such as data storage, chemical waste reduction and reduction in overall process time. This paper is in viewgraph form.

Carbonization of heavy metal impregnated sewage sludge oriented towards potential co-disposal.

PubMed

Dou, Xiaomin; Chen, Dezhen; Hu, Yuyan; Feng, Yuheng; Dai, Xiaohu

2017-01-05

Sewage sludge (SS) is adopted as a stabilizer to immobilize externally impregnated heavy metals through carbonization oriented towards the co-disposal of SS and some hazardous wastes. Firstly Cu and Pb were impregnated into SS to ascertain the impregnating capacity and leaching behaviours of heavy metals in the resulting sewage sludge char (SSC). Meanwhile, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to detect the heavy metal phase in the SSC. The results showed that within 400-800°C and an impregnating concentration ≨0.5wt%, more than 90% of the externally impregnated Cu and Pb were remained in the SSC and immobilized. And higher temperatures helped produce non-hazardous SSC. In addition, SEM and XRD analyses revealed that externally impregnated heavy metals could be converted into stable forms and evenly distributed throughout the SSC. In the second step municipal solid waste incineration fly ash (FA) was kneaded into SS and subjected to carbonization; it has been proved that the heavy metals in FA can be well immobilized in the resulting char when FA: SS mass ratio is 1:5. Those results show that sewage sludge can be co-carbonized with wastes contaminated with heavy metals to achieve co-disposal. Copyright © 2016 Elsevier B.V. All rights reserved.

Metal accumulation strategies in plants spontaneously inhabiting Zn-Pb waste deposits.

PubMed

Wójcik, Małgorzata; Sugier, Piotr; Siebielec, Grzegorz

2014-07-15

Metal (Zn, Pb, Cd, Cu, Ni, Cr) accumulation in shoots of 38 plant species spontaneously colonizing three Zn-Pb waste deposits in southern Poland was studied in order to find out if the age of the waste (30-130 years) or its type (slag or flotation residues) influence metal content in plants and to identify species potentially suitable for biomonitoring and phytoremediation. The total metal concentrations in the waste upper layers ranged from 7300 to 171,790 mg kg(-1) for Zn, from 1390 to 22,265 mg kg(-1) for Pb, and from 66 to 1,464 mg kg(-1) for Cd, whereas CaCl2-extracted fractions accounted for 0.034-0.11 %, 0.005-0.03 %, and 0.28-0.62 % of total Zn, Pb and Cd concentrations, respectively. The concentrations of Cu, Ni, and Cr in substrates and in plants were low and ranged within the background values. Metal accumulation in plant shoots was poorly correlated with both total and CaCl2-extracted forms of metals in the substrate and was highly variable among species and also specimens of the same species. The highest mean concentrations of Zn, Pb and Cd were found in Anthyllis vulneraria L. (901.5 mg kg(-1)), Echium vulgare L. (116.92 mg kg(-1)), and Hieracium piloselloides Vill. (26.86 mg kg(-1)), respectively. Besides Reseda lutea L., no species appeared to be a good indicator of polymetallic environment pollution based on chemical analysis of shoots; however, metal accumulation in the whole plant communities of a particular contaminated area might be an accurate tool for assessment of metal transfer to vegetation irrespective of the type or age of the waste. All the species studied developed a metal exclusion strategy, thus exhibiting potential for phytostabilization of metalliferous wastelands. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of a novel wet oxidation process for hazardous and mixed wastes

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

Dhooge, P.M.

1994-12-31

Many DOE waste streams and remediates contain complex and variable mixtures of organic compounds, toxic metals, and radionuclides. These materials are often dispersed in organic or inorganic matrices, such as personal protective equipment, various sludges, soils, and water. The over all objective of the effort described here is to develop a novel catalytic wet oxidation process for the treatment of these multi-component wastes, with the aim of providing a versatile, non-thermal method which will destroy hazardous organic compounds while simultaneously containing and concentrating toxic and radioactive metals for recovery or disposal in a readily stabilized matrix. The DETOX process usesmore » a unique combination of metal catalysts to increase the rate of oxidation of organic materials. The metal catalysts are in the form of salts dissolved in a dilute acid solution. A typical catalyst composition is 60% ferric chloride, 3--4% hydrochloric acid, 0.13% platinum ions, and 0.13% ruthenium ions in a water solution. The catalyst solution is maintained at 423--473 K. Wastes are introduced into contact with the solution, where their organic portion is oxidized to carbon dioxide and water. If the organic portion is chlorinated, hydrogen chloride will be produced as a product. The process is a viable alternative to incineration for the treatment of organic mixed wastes. Estimated costs for waste treatment using the process are from $2.50/kg to $25.00/kg, depending on the size of the unit and the amount of waste processed. Process units can be mobile for on-site treatment of wastes. Results from phase 1 and 2, design and engineering studies, are described.« less

Degradation of organic pollutants by Ag, Cu and Sn doped waste non-metallic printed circuit boards.

PubMed

Ramaswamy, Kadari; Radha, Velchuri; Malathi, M; Vithal, Muga; Munirathnam, Nagegownivari R

2017-02-01

The disposal and reuse of waste printed circuit boards have been the major global concerns. Printed circuit boards, a form of Electronic waste (hereafter e-waste), have been chemically processed, doped with Ag + , Cu 2+ and Sn 2+ , and used as visible light photocatalysts against the degradation of methylene blue and methyl violet. The elemental analyses of pristine and metal doped printed circuit board were obtained using energy dispersive X-ray fluorescence (EDXRF) spectra and inductively coupled plasma optical emission spectroscopy (ICP-OES). The morphology of parent and doped printed circuit board was obtained from scanning electron microscopy (SEM) measurements. The photocatalytic activity of parent and metal doped samples was carried out for the decomposition of organic pollutants, methylene blue and methyl violet, under visible light irradiation. Metal doped waste printed circuit boards (WPCBs) have shown higher photocatalytic activity against the degradation of methyl violet and methylene blue under visible light irradiation. Scavenger experiments were performed to identify the reactive intermediates responsible for the degradation of methylene blue and methyl violet. The reactive species responsible for the degradation of MV and MB were found to be holes and hydroxyl radicals. A possible mechanism of degradation of methylene blue and methyl violet is given. The stability and reusability of the catalysts are also investigated. Copyright © 2016. Published by Elsevier Ltd.

Scientific Background for Processing of Aluminum Waste

NASA Astrophysics Data System (ADS)

Kononchuk, Olga; Alekseev, Alexey; Zubkova, Olga; Udovitsky, Vladimir

2017-11-01

Changing the source of raw materials for producing aluminum and the emergence of a huge number of secondary alumina waste (foundry slag, sludge, spent catalysts, mineral parts of coal and others that are formed in various industrial enterprises) require the creation of scientific and theoretical foundations for their processing. In this paper, the aluminum alloys (GOST 4784-97) are used as an aluminum raw material component, containing the aluminum component produced as chips in the machine-building enterprises. The aluminum waste is a whole range of metallic aluminum alloys including elements: magnesium, copper, silica, zinc and iron. Analysis of the aluminum waste A1- Zn-Cu-Si-Fe shows that depending on the content of the metal the dissolution process of an aluminum alloy should be treated as the result of the chemical interaction of the metal with an alkaline solution. It is necessary to consider the behavior of the main components of alloys in an alkaline solution as applied to the system Na2O - Al2O3 - SiO2 - CO2 - H2O.

Refining technology for the recycling of stainless steel radioactive scrap metals, FY 94 bi-annual report

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

Mizia, R.E.; Atteridge, D.G.; Buckentin, J.

1994-08-01

The research addressed under this project is the recycling of metallic nuclear-related by-product materials under the direction of Westinghouse Idaho Nuclear Company (WINCO). The program addresses the recycling of radioactive scrap metals (RSM) for beneficial re-use within the DOE complex; in particular, this program addresses the recycling of stainless steel RSM. It is anticipated that various stainless steel components under WINCO control at the Idaho Falls Engineering Laboratory (INEL), such as fuel pool criticality barriers and fuel storage racks will begin to be recycled in FY94-95. The end product of this recycling effort is expected to be waste and overpackmore » canisters for densified high level waste for the Idaho Waste Immobilization Facility and/or the Universal Canister System for dry (interim) storage of spent fuel. The specific components of this problem area that are presently being, or have been, addressed by CAAMSEC are: (1) the melting/remelting of stainless steel RSM into billet form; (2) the melting/remelting initial research focus will be on the use of radioactive surrogates to study; (3) the cost effectiveness of RSM processing oriented towards privatization of RSM reuse and/or resale. Other components of this problem that may be addressed under program extension are: (4) the melting/remelting of carbon steel; (5) the processing of billet material into product form which shall meet all applicable ASTM requirements; and, (6) the fabrication of an actual prototypical product; the present concept of an end product is a low carbon Type 304/316 stainless steel cylindrical container for densified and/or vitrified high level radioactive waste and/or the Universal Canister System for dry (interim) storage of spent fuel. The specific work reported herein covers the melting/remelting of stainless steel {open_quotes}scrap{close_quotes} metal into billet form and the study of surrogate material removal effectiveness by various remelting techniques.« less

Treatment of halogen-containing waste and other waste materials

DOEpatents

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

1997-01-01

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

Treatment of halogen-containing waste and other waste materials

DOEpatents

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

1997-03-18

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

Bench-scale operation of the DETOX wet oxidation process for mixed waste

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

Dhooge, P.M.

1993-01-01

Waste matrices containing organics, radionuclides, and metals pose difficult problems in waste treatment and disposal when the organic compounds and/or metals are considered to be hazardous. A means of destroying hazardous organic components while safely containing and concentrating metals would be extremely useful in mixed waste volume reduction or conversion to a radioactive-only form. Previous studies have found the DETOX, a patented process utilizing a novel catalytic wet oxidation by iron(III) oxidant, cold have successful application to mixed wastes, and to many other waste types. This paper describes the results of bench scale studies of DETOX applied to the componentsmore » of liquid mixed wastes, with the goal of establishing parameters for the design of a prototype waste treatment unit. Apparent organic reaction rate orders, and the dependence of apparent reaction rate on the contact area, were measured for vacuum pump oil, scintillation fluids, and trichloroethylene. It was found that reaction rate was proportional to contact area above about 2.% w/w loading of organic. Oxidations in a 4 liter. volume, mixed bench top reactor have given destruction efficiencies of 99.9999+% for common organics. Reaction rates achieved in the mixedbench top reactor were one to two orders of magnitude greater than had been achieved in unmixed reactions; a thoroughly mixed reactor should be capable of oxidizing 10. to 100.+ grams of organic per liter-hour,depending on the nature and concentration of the organic.« less

Bench-scale operation of the DETOX wet oxidation process for mixed waste

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

Dhooge, P.M.

1993-03-01

Waste matrices containing organics, radionuclides, and metals pose difficult problems in waste treatment and disposal when the organic compounds and/or metals are considered to be hazardous. A means of destroying hazardous organic components while safely containing and concentrating metals would be extremely useful in mixed waste volume reduction or conversion to a radioactive-only form. Previous studies have found the DETOX, a patented process utilizing a novel catalytic wet oxidation by iron(III) oxidant, cold have successful application to mixed wastes, and to many other waste types. This paper describes the results of bench scale studies of DETOX applied to the componentsmore » of liquid mixed wastes, with the goal of establishing parameters for the design of a prototype waste treatment unit. Apparent organic reaction rate orders, and the dependence of apparent reaction rate on the contact area, were measured for vacuum pump oil, scintillation fluids, and trichloroethylene. It was found that reaction rate was proportional to contact area above about 2.% w/w loading of organic. Oxidations in a 4 liter. volume, mixed bench top reactor have given destruction efficiencies of 99.9999+% for common organics. Reaction rates achieved in the mixedbench top reactor were one to two orders of magnitude greater than had been achieved in unmixed reactions; a thoroughly mixed reactor should be capable of oxidizing 10. to 100.+ grams of organic per liter-hour,depending on the nature and concentration of the organic.« less

Zirconia ceramics for excess weapons plutonium waste

NASA Astrophysics Data System (ADS)

Gong, W. L.; Lutze, W.; Ewing, R. C.

2000-01-01

We synthesized a zirconia (ZrO 2)-based single-phase ceramic containing simulated excess weapons plutonium waste. ZrO 2 has large solubility for other metallic oxides. More than 20 binary systems A xO y-ZrO 2 have been reported in the literature, including PuO 2, rare-earth oxides, and oxides of metals contained in weapons plutonium wastes. We show that significant amounts of gadolinium (neutron absorber) and yttrium (additional stabilizer of the cubic modification) can be dissolved in ZrO 2, together with plutonium (simulated by Ce 4+, U 4+ or Th 4+) and impurities (e.g., Ca, Mg, Fe, Si). Sol-gel and powder methods were applied to make homogeneous, single-phase zirconia solid solutions. Pu waste impurities were completely dissolved in the solid solutions. In contrast to other phases, e.g., zirconolite and pyrochlore, zirconia is extremely radiation resistant and does not undergo amorphization. Baddeleyite (ZrO 2) is suggested as the natural analogue to study long-term radiation resistance and chemical durability of zirconia-based waste forms.

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

PubMed

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

2006-06-01

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

Comparative studies on acid leaching of zinc waste materials

NASA Astrophysics Data System (ADS)

Rudnik, Ewa; Włoch, Grzegorz; Szatan, Leszek

2017-11-01

Three industrial waste materials were characterized in terms of their elemental and phase compositions, leaching behaviour in 10% sulfuric acid solution as well as leaching thermal effects. Slag from melting of mixed metallic scrap contained about 50% Zn and 10% Pb. It consisted mainly of various oxides and oxy-chlorides of metals. Zinc spray metallizing dust contained about 77% Zn in form of zinc and/or zinc-iron oxides, zinc metal and Zn-Fe intermetallic. Zinc ash from hot dip galvanizing was a mixture of zinc oxide, metallic zinc and zinc hydroxide chloride and contained about 80% Zn. Dissolution efficiency of zinc from the first material was 80% (independently on the solid to liquid ratio, 50-150 kg/m3), while decrease of the efficacy from 80% to 60% with increased solid to liquid ratio for the two remaining materials was observed. Both increase in the temperature (20 °C to 35 °C) and agitation rate (300 rpm to 900 rpm) did not improve seriously the leaching results. In all cases, transfer of zinc ions to the leachate was accompanied by different levels of solution contamination, depending on the type of the waste. Leaching of the materials was exothermic with the similar reaction heats for two high oxide-type products (slag, zinc ash) and higher values for the spray metallizing dust.

Electrochemical/Pyrometallurgical Waste Stream Processing and Waste Form Fabrication

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

Steven Frank; Hwan Seo Park; Yung Zun Cho

This report summarizes treatment and waste form options being evaluated for waste streams resulting from the electrochemical/pyrometallurgical (pyro ) processing of used oxide nuclear fuel. The technologies that are described are South Korean (Republic of Korea – ROK) and United States of America (US) ‘centric’ in the approach to treating pyroprocessing wastes and are based on the decade long collaborations between US and ROK researchers. Some of the general and advanced technologies described in this report will be demonstrated during the Integrated Recycle Test (IRT) to be conducted as a part of the Joint Fuel Cycle Study (JFCS) collaboration betweenmore » US Department of Energy (DOE) and ROK national laboratories. The JFCS means to specifically address and evaluated the technological, economic, and safe guard issues associated with the treatment of used nuclear fuel by pyroprocessing. The IRT will involve the processing of commercial, used oxide fuel to recover uranium and transuranics. The recovered transuranics will then be fabricated into metallic fuel and irradiated to transmutate, or burn the transuranic elements to shorter lived radionuclides. In addition, the various process streams will be evaluated and tested for fission product removal, electrolytic salt recycle, minimization of actinide loss to waste streams and waste form fabrication and characterization. This report specifically addresses the production and testing of those waste forms to demonstrate their compatibility with treatment options and suitability for disposal.« less

Using imaging spectroscopy to map acidic mine waste

USGS Publications Warehouse

Swayze, G.A.; Smith, K.S.; Clark, R.N.; Sutley, S.J.; Pearson, R.M.; Vance, J.S.; Hageman, P.L.; Briggs, P.H.; Meier, A.L.; Singleton, M.J.; Roth, S.

2000-01-01

The process of pyrite oxidation at the surface of mine waste may produce acidic water that is gradually neutralized as it drains away from the waste, depositing different Fe-bearing secondary minerals in roughly concentric zones that emanate from mine-waste piles. These Fe-bearing minerals are indicators of the geochemical conditions under which they form. Airborne and orbital imaging spectrometers can be used to map these mineral zones because each of these Fe-bearing secondary minerals is spectrally unique. In this way, imaging spectroscopy can be used to rapidly screen entire mining districts for potential sources of surface acid drainage and to detect acid producing minerals in mine waste or unmined rock outcrops. Spectral data from the AVIRIS instrument were used to evaluate mine waste at the California Gulch Superfund Site near Leadville, CO. Laboratory leach tests of surface samples show that leachate pH is most acidic and metals most mobile in samples from the inner jarosite zone and that leachate pH is near-neutral and metals least mobile in samples from the outer goethite zone.

Waste gasification vs. conventional Waste-to-Energy: a comparative evaluation of two commercial technologies.

PubMed

Consonni, Stefano; Viganò, Federico

2012-04-01

A number of waste gasification technologies are currently proposed as an alternative to conventional Waste-to-Energy (WtE) plants. Assessing their potential is made difficult by the scarce operating experience and the fragmentary data available. After defining a conceptual framework to classify and assess waste gasification technologies, this paper compares two of the proposed technologies with conventional WtE plants. Performances are evaluated by proprietary software developed at Politecnico di Milano and compared on the basis of a coherent set of assumptions. Since the two gasification technologies are configured as "two-step oxidation" processes, their energy performances are very similar to those of conventional plants. The potential benefits that may justify their adoption relate to material recovery and operation/emission control: recovery of metals in non-oxidized form; collection of ashes in inert, vitrified form; combustion control; lower generation of some pollutants. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

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

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

Geochemical position of Pb, Zn and Cd in soils near the Olkusz mine/smelter, South Poland: effects of land use, type of contamination and distance from pollution source.

PubMed

Chrastný, Vladislav; Vaněk, Aleš; Teper, Leslaw; Cabala, Jerzy; Procházka, Jan; Pechar, Libor; Drahota, Petr; Penížek, Vít; Komárek, Michael; Novák, Martin

2012-04-01

The soils adjacent to an area of historical mining, ore processing and smelting activities reflects the historical background and a mixing of recent contamination sources. The main anthropogenic sources of metals can be connected with historical and recent mine wastes, direct atmospheric deposition from mining and smelting processes and dust particles originating from open tailings ponds. Contaminated agriculture and forest soil samples with mining and smelting related pollutants were collected at different distances from the source of emission in the Pb-Zn-Ag mining area near Olkusz, Upper Silesia to (a) compare the chemical speciation of metals in agriculture and forest soils situated at the same distance from the point source of pollution (paired sampling design), (b) to evaluate the relationship between the distance from the polluter and the retention of the metals in the soil, (c) to describe mineralogy transformation of anthropogenic soil particles in the soils, and (d) to assess the effect of deposited fly ash vs. dumped mining/smelting waste on the mobility and bioavailability of metals in the soil. Forest soils are much more affected with smelting processes than agriculture soils. However, agriculture soils suffer from the downward metal migration more than the forest soils. The maximum concentrations of Pb, Zn, and Cd were detected in a forest soil profile near the smelter and reached about 25 g kg(- 1), 20 g kg(- 1) and 200 mg kg(- 1) for Pb, Zn and Cd, respectively. The metal pollutants from smelting processes are less stable under slightly alkaline soil pH then acidic due to the metal carbonates precipitation. Metal mobility ranges in the studied forest soils are as follows: Pb > Zn ≈ Cd for relatively circum-neutral soil pH (near the smelter), Cd > Zn > Pb for acidic soils (further from the smelter). Under relatively comparable pH conditions, the main soil properties influencing metal migration are total organic carbon and cation exchange capacity. The mobilization of Pb, Zn and Cd in soils depends on the persistence of the metal-containing particles in the atmosphere; the longer the time, the more abundant the stable forms. The dumped mining/smelting waste is less risk of easily mobilizable metal forms, however, downward metal migration especially due to the periodical leaching of the waste was observed.

[Recent advance in solidification/stabilization technology for the remediation of heavy metals-contaminated soil].

PubMed

Hao, Han-zhou; Chen, Tong-bin; Jin, Meng-gui; Lei, Mei; Liu, Cheng-wu; Zu, Wen-pu; Huang, Li-mi

2011-03-01

Remediation of heavy metals-contaminated soil is still a difficulty and a hotspot of international research projects. At present, the technologies commonly adopted for the remediation of contaminated sites mainly include excavation, solidification/stabilization (S/S), soil washing, soil vapor extraction (SVE), thermal treatment, and bioremediation. Based on the S/S technical guidelines of Unite State Environmental Protection Agency (EPA) and United Kingdom Environment Agency (EA) and the domestic and foreign patents, this paper introduced the concepts of S/S and its development status at home and abroad, and discussed its future development directions. Solidification refers to a process that binds contaminated media with a reagent, changing the media's physical properties via increasing its compressive strength, decreasing its permeability, and encapsulating the contaminants to form a solid material. Stabilization refers to the process that involves a chemical reaction which reduces the leachability of a waste, chemically immobilizes the waste and reduces its solubility, making the waste become less harmful or less mobile. S/S technology includes cement solidification, lime pozzolanic solidification, plastic materials stabilization, vitrification, and regent-based stabilization. Stabilization (or immobilization) treatment processes convert contaminants to less mobile forms through chemical or thermal interactions. In stabilization technology, the aim of adding agents is to change the soil physical and chemical properties through pH control technology, redox potential technology, precipitation techniques, adsorption technology, and ion-exchange technology that change the existing forms of heavy metals in soil, and thus, reduce the heavy metals bioavailability and mobility. This review also discussed the S/S evaluation methods, highlighted the need to enhance S/S technology in the molecular bonding, soil polymers, and formulation of China's S/S technical guidelines.

SOx/NOx sorbent and process of use

DOEpatents

Ziebarth, M.S.; Hager, M.J.; Beeckman, J.W.; Plecha, S.

1993-01-19

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 600 C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and dripped to form the stabilizing spheroidal alumina particles. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

SOX/NOX sorbent and process of use

DOEpatents

Ziebarth, M.S.; Hager, M.J.; Beeckman, J.W.; Plecha, S.

1995-05-09

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 600 C is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and dripped to form the stabilized spheroidal alumina particles. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths. 3 figs.

SOX/NOX sorbent and process of use

DOEpatents

Ziebarth, Michael S.; Hager, Michael J.; Beeckman, Jean W.; Plecha, Stanislaw

1995-01-01

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 600.degree. C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and dripped to form the stabilized spheroidal alumina particles. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

SOx/NOx sorbent and process of use

DOEpatents

Ziebarth, Michael S.; Hager, Michael J.; Beeckman, Jean W.; Plecha, Stanislaw

1993-01-19

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 600.degree. C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and dripped to form the stabilizing spheroidal alumina particles. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

Development of materials for the removal of metal ions from radioactive and non-radioactive waste streams

NASA Astrophysics Data System (ADS)

Hasan, Md. Shameem

Nuclear wastes that were generated during cold-war era from various nuclear weapon programs are presently stored in hundreds of tanks across the United States. The composition of these wastes is rather complex containing both radionuclides and heavy metals, such as 137Cs, 90Sr, Al, Pb, Cr, and Cd. In this study, chitosan based biosorbents were prepared to adsorb some of these metal ions. Chitosan is a partially acetylated glucosamine biopolymer encountered in the cell walls of fungi. In its natural form this material is soft and has a tendency to agglomerate or form gels. Various methods were used to modify chitosan to avoid these problems. Chitosan is generally available commercially in the form of flakes. For use in an adsorption system, chitosan was made in the form of beads to reduce the pressure drop in an adsorption column. In this research, spherical beads were prepared by mixing chitosan with perlite and then by dropwise addition of the slurry mixture into a NaOH precipitation bath. Beads were characterized using Fourier Transform InfraRed Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy dispersive spectroscopy (EDS), Tunneling Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), and Thermogravimetric Analysis (TGA). The SEM, EDS, and TEM data indicated that the beads were porous in nature. The TGA data showed that bead contained about 32% chitosan. The surface area, pore volume, and porosity of the beads were determined from the BET surface area that was measured using N2 as adsorbate at 77K. Adsorption and desorption of Cr(VI), Cr(III), Cd(II), U(VI), Cu(II), from aqueous solutions of these metal ions were studied to evaluate the adsorption capacities of the beads for these metals ions. Equilibrium adsorption data of these metals on the beads were found to correlate well with the Langmuir isotherm equation. Chitosan coated perlite beads had negligible adsorption capacity for Sr(II) and Cs(I). It was found that Fullers earth had very good capacity for these two metals. However, the mechanical strength of Fullers earth granules available commercially was not sufficient for use in a column. In this study chitosan was used as a binder to make Fullers earth beads and were used for adsorption of Cs(I) and Sr(II). (Abstract shortened by UMI.)

Metal leaching from refinery waste hydroprocessing catalyst.

PubMed

Marafi, Meena; Rana, Mohan S

2018-05-18

The present study aims to develop an eco-friendly methodology for the recovery of nickel (Ni), molybdenum (Mo), and vanadium (V) from the refinery waste spent hydroprocessing catalyst. The proposed process has two stages: the first stage is to separate alumina, while the second stage involves the separation of metal compounds. The effectiveness of leaching agents, such as NH 4 OH, (NH 4 ) 2 CO 3 , and (NH 4 ) 2 S 2 O 8 , for the extraction of Mo, V, Ni, and Al from the refinery spent catalyst has been reported as a function of reagent concentration (0.5 to 2.0 molar), leaching time (1 to 6 h), and temperature (35 to 60°C). The optimal leaching conditions were achieved to obtain the maximum recovery of Mo, Ni, and V metals. The effect of the mixture of multi-ammonium salts on the metal extraction was also studied, which showed an adverse effect for Ni and V, while marginal improvement was observed for Mo leaching. The ammonium salts can form soluble metal complexes, in which stability or solubility depends on the nature of ammonium salt and the reaction conditions. The extracted metals and support can be reused to synthesize a fresh hydroprocessing catalyst. The process will reduce the refinery waste and recover the expensive metals. Therefore, the process is not only important from an environmental point of view but also vital from an economic perspective.

Non-combustible waste vitrification with plasma torch melter.

PubMed

Park, J K; Moon, Y P; Park, B C; Song, M J; Ko, K S; Cho, J M

2001-05-01

Non-combustible radioactive wastes generated from Nuclear Power Plants (NPPs) are composed of concrete, glass, asbestos, metal, sand, soil, spent filters, etc. The melting tests for concrete, glass, sand, and spent filters were carried out using a 60 kW plasma torch system. The surrogate wastes were prepared for the tests. Non-radioactive Co and Cs were added to the surrogates in order to simulate the radioactive waste. Several kinds of surrogate prepared by their own mixture or by single waste were melted with the plasma torch system to produce glassy waste forms. The characteristics of glassy waste forms were examined for the volume reduction factor (VRF) and the leach rate. The VRFs were estimated through the density measurement of the surrogates and the glassy waste forms, and were turned out to be 1.2-2.4. The EPA (Environmental Protection Agency) Toxicity Characteristic Leaching Procedure (TCLP) was used to determine the leach resistance for As, Ba, Hg, Pb, Cd, Cr, Se, Co, and Cs. The leaching index was calculated using the total content of each element in both the waste forms and the leachant. The TCLP tests resulted in that the leach rates for all elements except Co and Cs were lower than those of the Universal Treatment Standard (UTS) limits. There were no UTS limits for Co and Cs, and their leach rate & index from the experiments were resulted in around 10 times higher than those of other elements.

From agricultural use of sewage sludge to nutrient extraction: A soil science outlook.

PubMed

Kirchmann, Holger; Börjesson, Gunnar; Kätterer, Thomas; Cohen, Yariv

2017-03-01

The composition of municipal wastewater and sewage sludge reflects the use and proliferation of elements and contaminants within society. In Sweden, official statistics show that concentrations of toxic metals in municipal sewage sludge have steadily decreased, by up to 90 %, since the 1970s, due to environmental programmes and statutory limits on metals in sludge and soil. Results from long-term field experiments show that reduced metal pollution during repeated sewage sludge application has reversed negative trends in soil biology. Despite this Swedish success story, organic waste recycling from Swedish towns and cities to arable land is still limited to only about 20 % of the total amount produced. Resistance among industries and consumers to products grown on land treated with sewage sludge may not always be scientifically grounded; however, there are rational obstacles to application of sewage sludge to land based on its inherent properties rather than its content of pollutants. We argue that application of urban organic wastes to soil is an efficient form of recycling for small municipalities, but that organic waste treatment from large cities requires other solutions. The large volumes of sewage sludge collected in towns and cities are not equitably distributed back to arable land because of the following: (i) The high water and low nutrient content in sewage sludge make long-distance transportation too expensive; and (ii) the low plant availability of nutrients in sewage sludge results in small yield increases even after many years of repeated sludge addition. Therefore, nutrient extraction from urban wastes instead of direct organic waste recycling is a possible way forward. The trend for increased combustion of urban wastes will make ash a key waste type in future. Combustion not only concentrates the nutrients in the ash but also leads to metal enrichment; hence, direct application of the ash to land is most often not possible. However, inorganic fertiliser (e.g. mono-ammonium phosphate fertiliser, MAP) can be produced from metal-contaminated sewage sludge ash in a process whereby the metals are removed. We argue that the view on organic waste recycling needs to be diversified in order to improve the urban-rural nutrient cycle, since only recycling urban organic wastes directly is not a viable option to close the urban-rural nutrient cycle. Recovery and recycling of nutrients from organic wastes are a possible solution. When organic waste recycling is complemented by nutrient extraction, some nutrient loops within society can be closed, enabling more sustainable agricultural production in future.

Properties of a Novel Ion-Exchange Film

NASA Technical Reports Server (NTRS)

Street, Kenneth W.; Hill, Carol M.; Philipp, Warren H.; Tanner, Stephen P.; Gorse, Joseph; Lusk, Amy; Taylor, Jason; Dickens, Jason

2002-01-01

A new ion-exchange material (based on polyacrylic acid) and some of its analytical applications have been reported. This paper contains data on the ion-exchange properties of the film form of the material and its potential application to the decontamination of waste water and drinking water. The film has a high exchange capacity of 5 to 6 meq/g and a pK(sub a) of 5.7. The calcium form is the most effective for removing metal ions from solution, and the optimum pH range is between 5 and 7. The exchange rates are slower for the film than for bead and powder forms of the ion-exchange material; otherwise, the properties are similar. The film is effective when hard water solutions are employed and also when metal ions are in the complex matrix of waste water from electroplating. The film can be used in flow systems having a flow channel large enough to allow passage of turbid solutions.

Properties of a Novel Ion-Exchange Film

NASA Technical Reports Server (NTRS)

Street, Kenneth W.; Hill, Carol M.; Philipp, Warren H.; Tanner, Stephen P.; Gorse, Joseph; Lusk, Amy; Taylor, Jason; Dickens, Jason

2004-01-01

A new ion-exchange material (based on polyacrylic acid) and some of its analytical applications have been reported. This paper contains data on the ion-exchange properties of the film form of the material and its potential application to the decontamination of waste water and drinking water. The film has a high exchange capacity of 5 to 6 meq/g and a pK(sub a) of 5.7. The calcium form is the most effective for removing metal ions from solution, and the optimum pH range is between 5 and 7. The exchange rates are slower for the film than for bead and powder forms of the ion-exchange material; otherwise, the properties are similar. The film is effective when hard water solutions are employed and also when metal ions are in the complex matrix of waste water from electroplating. The film can be used in flow systems having a flow channel large enough to allow passage of turbid solutions.

Influence of supercritical water treatment on heavy metals in medical waste incinerator fly ash.

PubMed

Bo, Da; Zhang, Fu-Shen; Zhao, Lijuan

2009-10-15

In this work, medical waste (MW) incinerator fly ashes from different types of incinerators were subjected to supercritical water (SCW) and SCW+H(2)O(2) (SCWH) treatments. Sequential extraction experiments showed that, after SCW treatment, heavy metals in exchangeable and carbonate forms in the ashes could be transferred into other relatively stable forms, e.g., Ba and Cr into residual fraction, Cu and Pb into organic matter fraction. SCWH treatment could stabilize heavy metals in Fe-Mn oxides and residual fractions. However, the behavior of As was quite different from heavy metals, which could be leached out from residue fraction after SCW and SWCH treatments. The leached As tended to absorb onto Fe-Mn oxides and organic matters under near neutral environment, but it could react with Ca(2+) at lower pH, increasing the mobility of this element. Therefore, it is necessary to neutralize acidic ash to near neutral condition before subjecting it to SCW and SCWH treatments so as to effectively stabilize hazardous elements in the ash. Consequently, it is believed that SCWH treatment is an effective alternative for hazardous elements detoxification in MW fly ash.

Fabricating Structural Stiffeners By Superplastic Forming

NASA Technical Reports Server (NTRS)

Bales, Thomas T.; Shinn, Joseph M., Jr.; Hales, Stephen J.; James, William F.

1994-01-01

Superplastic forming (SPF) of aluminum alloys effective technique for making strong, lightweight structural components conforming to close dimensional tolerances. Technique applied in experimental fabrication of prototypes of stiffening ribs for cylindrical tanks. When making structural panel, stiffening ribs spot-welded to metal skin. Use of discrete eliminates machining waste, and use of SPF. Cost of fabrication reduced.

Plasma methods for metals recovery from metal-containing waste.

PubMed

Changming, Du; Chao, Shang; Gong, Xiangjie; Ting, Wang; Xiange, Wei

2018-04-27

Metal-containing waste, a kind of new wastes, has a great potential for recycling and is also difficult to deal with. Many countries pay more and more attention to develop the metal recovery process and equipment of this kind of waste as raw material, so as to solve the environmental pollution and comprehensively utilize the discarded metal resources. Plasma processing is an efficient and environmentally friendly way for metal-containing waste. This review mainly discuss various metal-containing waste types, such as printed circuit boards (PCBs), red mud, galvanic sludge, Zircon, aluminium dross and incinerated ash, and the corresponding plasma methods, which include DC extended transferred arc plasma reactor, DC non-transferred arc plasma torch, RF thermal plasma reactor and argon and argon-hydrogen plasma jets. In addition, the plasma arc melting technology has a better purification effect on the extraction of useful metals from metal-containing wastes, a great capacity of volume reduction of waste materials, and a low leaching toxicity of solid slag, which can also be used to deal with all kinds of metal waste materials, having a wide range of applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Turning Waste Chemicals into Wealth-A New Approach To Synthesize Efficient Cathode Material for an Li-O2 Battery.

PubMed

Yao, Ying; Wu, Feng

2017-09-20

An Li-O 2 battery requires the oxygen-breathing cathode to be highly electronically conductive, rapidly oxygen diffusive, structurally stable, and often times electrocatalytically active. Catalyst-decorated porous carbonaceous materials are the chosen air cathode in this regard. Alternatively, biomass-derived carbonaceous materials possess great ability to remove heavy and toxic metal ions from waste, forming a metal-adsorbed porous carbonaceous material. The similar structure between the air cathode and the metal-adsorbed biomass-derived carbon nicely bridges these two irrelevant areas. In this study, we investigated the electrochemical activity of a biochar material Ag-ESB directly synthesized from ethanol sludge residue in a rechargeable aprotic Li-O 2 battery. Ag ions were adsorbed from sewage and became Ag nanoparticles with uniform coverage on the biochar surface. The as-prepared material exhibits good electrochemical behavior in battery testing, especially toward the battery efficiency and cyclability. This study provides the possibility of synthetically efficient cathode material by reusing "waste" such as biofuel sludge residue. It is an economically and environmentally friendly approach both for an energy-storage system and for waste recycling.

Biotechnology in the management and resource recovery from metal bearing solid wastes: Recent advances.

PubMed

Sethurajan, Manivannan; van Hullebusch, Eric D; Nancharaiah, Yarlagadda V

2018-04-01

Solid metalliferous wastes (sludges, dusts, residues, slags, red mud and tailing wastes) originating from ferrous and non-ferrous metallurgical industries are a serious environmental threat, when waste management practices are not properly followed. Metalliferous wastes generated by metallurgical industries are promising resources for biotechnological extraction of metals. These wastes still contain significant amounts of valuable non-ferrous metals, sometimes precious metals and also rare earth elements. Elemental composition and mineralogy of the metallurgical wastes is dependent on the nature of mining site and composition of primary ores mined. Most of the metalliferous wastes are oxidized in nature and contain less/no reduced sulfidic minerals (which can be quite well processed by biohydrometallurgy). However, application of biohydrometallurgy is more challenging while extracting metals from metallurgical wastes that contain oxide minerals. In this review, origin, elemental composition and mineralogy of the metallurgical solid wastes are presented. Various bio-hydrometallurgical processes that can be considered for the extraction of non-ferrous metals from metal bearing solid wastes are reviewed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Environmental impacts of unmanaged solid waste at a former base metal mining and ore processing site (Kirki, Greece).

PubMed

Liakopoulos, Alexandros; Lemière, Bruno; Michael, Konstantinos; Crouzet, Catherine; Laperche, Valérie; Romaidis, Ioannis; Drougas, Iakovos; Lassin, Arnault

2010-11-01

The Kirki project aimed to identify, among the mining waste abandoned at a mine and processing plant, the most critical potential pollution sources, the exposed milieus and the main pathways for contamination of a littoral area. This was accompanied by the definition of a monitoring network and remedial options. For this purpose, field analytical methods were extensively used to allow a more precise identification of the source, to draw relevant conceptual models and outline a monitoring network. Data interpretation was based on temporal series and on a geographical model. A classification method for mining waste was established, based on data on pollutant contents and emissions, and their long-term pollution potential. Mining waste present at the Kirki mine and plant sites comprises (A) extraction waste, mainly metal sulfide-rich rocks; (B) processing waste, mainly tailings, with iron and sulfides, sulfates or other species, plus residues of processing reagents; and (C) other waste, comprising leftover processing reagents and Pb-Zn concentrates. Critical toxic species include cadmium and cyanide. The stormy rainfall regime and hilly topography favour the flush release of large amounts of pollutants. The potential impacts and remedial options vary greatly. Type C waste may generate immediate and severe chemical hazards, and should be dealt with urgently by careful removal, as it is localised in a few spots. Type B waste has significant acid mine drainage potential and contains significant amounts of bioavailable heavy metals and metalloids, but they may also be released in solid form into the surface water through dam failure. The most urgent action is thus dams consolidation. Type A waste is by far the most bulky, and it cannot be economically removed. Unfortunately, it is also the most prone to acid mine drainage (seepage pH 1 to 2). This requires neutralisation to prevent acid water accelerating heavy metals and metalloids transfer. All waste management options require the implementation of a monitoring network for the design of a remediation plan, efficiency control, and later, community alert in case of accidental failure of mitigation/remediation measures. A network design strategy based on field measurements, laboratory validation and conceptual models is proposed.

Mercury-impacted scrap metal: Source and nature of the mercury.

PubMed

Finster, Molly E; Raymond, Michelle R; Scofield, Marcienne A; Smith, Karen P

2015-09-15

The reuse and recycling of industrial solid wastes such as scrap metal is supported and encouraged both internationally and domestically, especially when such wastes can be used as substitutes for raw material. However, scrap metal processing facilities, such as mini-mills, have been identified as a source of mercury (Hg) emissions in the United States. This research aims to better define some of the key issues related to the source and nature of mercury in the scrap metal waste stream. Overall, it is difficult to pinpoint the key mercury sources feeding into scrap metal recycling facilities, quantify their associated mercury concentrations, or determine which chemical forms are most significant. Potential sources of mercury in scrap metal include mercury switches from discarded vehicles, electronic-based scrap from household appliances and related industrial systems, and Hg-impacted scrap metal from the oil and gas industry. The form of mercury associated with scrap metal varies and depends on the source type. The specific amount of mercury that can be adsorbed and retained by steel appears to be a function of both metallurgical and environmental factors. In general, the longer the steel is in contact with a fluid or condensate that contains measurable concentrations of elemental mercury, the greater the potential for mercury accumulation in that steel. Most mercury compounds are thermally unstable at elevated temperatures (i.e., above 350 °C). As such, the mercury associated with impacted scrap is expected to be volatilized out of the metal when it is heated during processing (e.g., shredding or torch cutting) or melted in a furnace. This release of fugitive gas (Hg vapor) and particulates, as well as Hg-impacted bag-house dust and control filters, could potentially pose an occupational exposure risk to workers at a scrap metal processing facility. Thus, identifying and characterizing the key sources of Hg-impacted scrap, and understanding the nature and extent of associated releases, represent a practical research need that is essential for improving the environmental management of Hg-impacted scrap and assessing measures to protect workers from potential health and safety hazards that might be posed by mercury and Hg-impacted scrap. Copyright © 2015 Elsevier Ltd. All rights reserved.

Monitoring Metal Pollution Levels in Mine Wastes around a Coal Mine Site Using GIS

NASA Astrophysics Data System (ADS)

Sanliyuksel Yucel, D.; Yucel, M. A.; Ileri, B.

2017-11-01

In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey) are evaluated using geographical information system (GIS) tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

Comparative assessment of metallurgical recovery of metals from electronic waste with special emphasis on bioleaching.

PubMed

Priya, Anshu; Hait, Subrata

2017-03-01

Waste electrical and electronic equipment (WEEE) or electronic waste (e-waste) is one of the fastest growing waste streams in the urban environment worldwide. The core component of printed circuit board (PCB) in e-waste contains a complex array of metals in rich quantity, some of which are toxic to the environment and all of which are valuable resources. Therefore, the recycling of e-waste is an important aspect not only from the point of waste treatment but also from the recovery of metals for economic growth. Conventional approaches for recovery of metals from e-waste, viz. pyrometallurgical and hydrometallurgical techniques, are rapid and efficient, but cause secondary pollution and economically unviable. Limitations of the conventional techniques have led to a shift towards biometallurgical technique involving microbiological leaching of metals from e-waste in eco-friendly manner. However, optimization of certain biotic and abiotic factors such as microbial species, pH, temperature, nutrients, and aeration rate affect the bioleaching process and can lead to profitable recovery of metals from e-waste. The present review provides a comprehensive assessment on the metallurgical techniques for recovery of metals from e-waste with special emphasis on bioleaching process and the associated factors.

Foam and gel methods for the decontamination of metallic surfaces

DOEpatents

Nunez, Luis; Kaminski, Michael Donald

2007-01-23

Decontamination of nuclear facilities is necessary to reduce the radiation field during normal operations and decommissioning of complex equipment. In this invention, we discuss gel and foam based diphosphonic acid (HEDPA) chemical solutions that are unique in that these solutions can be applied at room temperature; provide protection to the base metal for continued applications of the equipment; and reduce the final waste form production to one step. The HEDPA gels and foams are formulated with benign chemicals, including various solvents, such as ionic liquids and reducing and complexing agents such as hydroxamic acids, and formaldehyde sulfoxylate. Gel and foam based HEDPA processes allow for decontamination of difficult to reach surfaces that are unmanageable with traditional aqueous process methods. Also, the gel and foam components are optimized to maximize the dissolution rate and assist in the chemical transformation of the gel and foam to a stable waste form.

Thermodynamic assessment of the rhodium-ruthenium-oxygen (Rh-Ru-O) system

NASA Astrophysics Data System (ADS)

Gossé, S.; Bordier, S.; Guéneau, C.; Brackx, E.; Domenger, R.; Rogez, J.

2018-03-01

Ruthenium (Ru) and rhodium (Rh) are abundant platinum-group metals formed during burn-up of nuclear fuels. Under normal operating conditions, Rh and Ru accumulate and predominantly form metallic precipitates with other fission products like Mo, Pd and Tc. In the framework of vitrification of high-level nuclear waste, these fission products are poorly soluble in molten glasses. They precipitate as metallic particles and oxide phases. Moreover, these Ru and Rh rich phases strongly depend on temperature and the oxygen fugacity of the glass melt. In case of severe accidental conditions with air ingress, oxidation of the Ru and Rh is possible. At low temperatures (T < 1422 K for rhodium sesquioxide and T < 1815 K for ruthenium dioxide), the formed oxides are relatively stable. On the other hand, at high temperatures (T > 1422 K for rhodium sesquioxide and T > 1815 K for ruthenium dioxide), they may decompose into (Rh)-FCC or (Ru)-HCP metallic phases and radiotoxic volatile gaseous species. A thermodynamic assessment of the Rh-Ru-O system will enable the prediction of: (1) the metallic and oxide phases that form during the vitrification of high-level nuclear wastes and (2) the release of volatile gaseous species during a severe accident. The Calphad method developed herein employs a thermodynamic approach in the investigation of the thermochemistry of rhodium and ruthenium at high temperatures. Current literature on the thermodynamic properties and phase diagram data enables preliminary thermodynamic assessments of the Rh-O and Ru-O systems. Additionally, select compositions in the ternary Rh-Ru-O system underwent experimental tests to complement data found in literature and to establish the phase equilibria in the ternary system.

Glass Ceramic Waste Forms for Combined CS+LN+TM Fission Products Waste Streams

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

Crum, Jarrod V.; Turo, Laura A.; Riley, Brian J.

2010-09-23

In this study, glass ceramics were explored as an alternative waste form for glass, the current baseline, to be used for immobilizing alkaline/alkaline earth + lanthanide (CS+LN) or CS+LN+transition metal (TM) fission-product waste streams generated by a uranium extraction (UREX+) aqueous separations type process. Results from past work on a glass waste form for the combined CS+LN waste streams showed that as waste loading increased, large fractions of crystalline phases precipitated upon slow cooling.[1] The crystalline phases had no noticeable impact on the waste form performance by the 7-day product consistency test (PCT). These results point towards the development ofmore » a glass ceramic waste form for treating CS+LN or CS+LN+TM combined waste streams. Three main benefits for exploring glass ceramics are: (1) Glass ceramics offer increased solubility of troublesome components in crystalline phases as compared to glass, leading to increased waste loading; (2) The crystalline network formed in the glass ceramic results in higher heat tolerance than glass; and (3) These glass ceramics are designed to be processed by the same melter technology as the current baseline glass waste form. It will only require adding controlled canister cooling for crystallization into a glass ceramic waste form. Highly annealed waste form (essentially crack free) with up to 50X lower surface area than a typical High-Level Waste (HLW) glass canister. Lower surface area translates directly into increased durability. This was the first full year of exploring glass ceramics for the Option 1 and 2 combined waste stream options. This work has shown that dramatic increases in waste loading are achievable by designing a glass ceramic waste form as an alternative to glass. Table S1 shows the upper limits for heat, waste loading (based on solubility), and the decay time needed before treatment can occur for glass and glass ceramic waste forms. The improvements are significant for both combined waste stream options in terms of waste loading and/or decay time required before treatment. For Option 1, glass ceramics show an increase in waste loading of 15 mass % and reduction in decay time of 24 years. Decay times of {approx}50 years or longer are close to the expected age of the fuel that will be reprocessed when the modified open or closed fuel cycle is expected to be put into action. Option 2 shows a 2x to 2.5x increase in waste loading with decay times of only 45 years. Note that for Option 2 glass, the required decay time before treatment is only 35 years because of the waste loading limits related to the solubility of MoO{sub 3} in glass. If glass was evaluated for similar waste loadings as those achieved in Option 2 glass ceramics, the decay time would be significantly longer than 45 years. These glass ceramics are not optimized, but already they show the potential to dramatically reduce the amount of waste generated while still utilizing the proven processing technology used for glass production.« less

A review on human health consequences of metals exposure to e-waste in China.

PubMed

Song, Qingbin; Li, Jinhui

2015-01-01

As the world's the largest dumping ground for e-waste, much of the population in China is exposed to heavy metals due to informal e-waste recycling processes. We reviewed recent studies on body burdens and human health effects of heavy metals from the major e-waste recycling sites in China. The results showed that the residents in the e-waste recycling sites are facing a potential higher daily intake of heavy metals. Moreover, heavy metals had entered subjects' bodies (the collected 5 tissue samples). Additionally,individual exposure to heavy metals in e-waste has also caused negative health outcomes,especially in neonates and children. We also recorded plausible outcomes associated with exposure to e wast (to heavy metals). A precautionary approach toward exposure, especially in neonates and children, therefore seems warranted.

Sox/Nox Sorbent And Process Of Use

DOEpatents

Ziebarth, Michael S.; Hager, Michael J.; Beeckman, Jean W.; Plecha, Stanislaw

1995-06-27

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 650.degree. C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and spray dried to form the stabilized spheroidal alumina particles having a particle size of less than 500 microns. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

Sox/Nox Sorbent And Process Of Use

DOEpatents

Ziebarth, Michael S.; Hager, Michael J.; Beeckman, Jean W.; Plecha, Stanislaw

1996-12-17

An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 650.degree. C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and spray dried to form the stabilized spheroidal alumina particles having a particle size of less than 500 microns. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

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

Finster, Molly E; Raymond, Michelle R.; Scofield, Marcienne A.

The reuse and recycling of industrial solid wastes such as scrap metal is supported and encouraged both internationally and domestically, especially when such wastes can be used as substitutes for raw material. However, scrap metal processing facilities, such as mini-mills, have been identified as a source of mercury (Hg) emissions in the United States. This research aims to better define some of the key issues related to the source and nature of mercury in the scrap metal waste stream. Overall, it is difficult to pinpoint the key mercury sources feeding into scrap metal recycling facilities, quantify their associated mercury concentrations,more » or determine which chemical forms are most significant. Potential sources of mercury in scrap metal include mercury switches from discarded vehicles, electronic-based scrap from household appliances and related industrial systems, and Hg-impacted scrap metal from the oil and gas industry. The form of mercury associated with scrap metal varies and depends on the source type. The specific amount of mercury that can be adsorbed and retained by steel appears to be a function of both metallurgical and environmental factors. In general, the longer the steel is in contact with a fluid or condensate that contains measurable concentrations of elemental mercury, the greater the potential for mercury accumulation in that steel. Most mercury compounds are thermally unstable at elevated temperatures (i.e., above 350°C). As such, the mercury associated with impacted scrap is expected to be volatilized out of the metal when it is heated during processing (e.g., shredding or torch cutting) or melted in a furnace. This release of fugitive gas (Hg vapor) and particulates, as well as Hg-impacted bag-house dust and control filters, could potentially pose an occupational exposure risk to workers at a scrap metal processing facility. Thus, identifying and characterizing the key sources of Hg-impacted scrap, and understanding the nature and extent of associated releases, represent a practical research need that is essential for improving the environmental management of Hg-impacted scrap and assessing measures to protect workers from potential health and safety hazards that might be posed by mercury and Hg-impacted scrap.« less

Chemical pyrolysis of E-waste plastics: Char characterization.

PubMed

Shen, Yafei; Chen, Xingming; Ge, Xinlei; Chen, Mindong

2018-05-15

This work studied the disposal of the non-metallic fraction from waste printed circuit board (NMF-WPCB) via the chemical pretreatments followed by pyrolysis. As a main heavy metal, the metallic Cu could be significantly removed by 92.4% using the HCl leaching process. Subsequently, the organic-Br in the brominated flame retardants (BFRs) plastics could be converted into HBr by pyrolysis. The alkali pretreatment was benefit for the Br fixation in the solid char. The Br fixation efficiency could reach up to 53.6% by the NaOH pretreatment followed by the pyrolysis process. The formed HBr could react with NaOH/KOH to generate the stabilized NaBr/KBr. Therefore, the integrated chemical pretreatment could be used for the eco-friendly disposal of the NMF-WPCB via pyrolysis. Copyright © 2018 Elsevier Ltd. All rights reserved.

INNOVATIVE PRACTICES FOR TREATING WASTE STREAMS CONTAINING HEAVY METALS: A WASTE MINIMIZATION APPROACH

EPA Science Inventory

Innovative practices for treating waste streams containing heavy metals often involve technologies or systems that either reduce the amount of waste generated or recover reusable resources. With the land disposal of metal treatment residuals becoming less of an accepted waste man...

Heavy metal contamination of surface soil in electronic waste dismantling area: site investigation and source-apportionment analysis.

PubMed

Jinhui Li; Huabo Duan; Pixing Shi

2011-07-01

The dismantling and disposal of electronic waste (e-waste) in developing countries is causing increasing concern because of its impacts on the environment and risks to human health. Heavy-metal concentrations in the surface soils of Guiyu (Guangdong Province, China) were monitored to determine the status of heavy-metal contamination on e-waste dismantling area with a more than 20 years history. Two metalloids and nine metals were selected for investigation. This paper also attempts to compare the data among a variety of e-waste dismantling areas, after reviewing a number of heavy-metal contamination-related studies in such areas in China over the past decade. In addition, source apportionment of heavy metal in the surface soil of these areas has been analysed. Both the MSW open-burning sites probably contained invaluable e-waste and abandoned sites formerly involved in informal recycling activities are the new sources of soil-based environmental pollution in Guiyu. Although printed circuit board waste is thought to be the main source of heavy-metal emissions during e-waste processing, requirement is necessary to soundly manage the plastic separated from e-waste, which mostly contains heavy metals and other toxic substances.

Environmental assessment of cement/foundry sludge products.

PubMed

Ruiz, M C; Andrés, A; Irabien, A

2003-05-01

This work deals with the environmental assessment of products based on cement and a waste from a cast iron activity. The waste is a foundry sludge from wastewater treatment previously characterized. This industrial waste shows a high water content (62.4%) and a hazardous behavior due to its metallic content mainly Zn (16.5%), together with a low fraction of organic pollutants, mainly phenolic compounds. The feasibility of immobilizing both typs of contaminants was studied using Portland cement as binder at different cement/waste ratios. The parameters of environmental control were the ecotoxicity and mobilization of zinc and phenolic compounds, all determined on the basis of compliance leaching tests. The acid neutralization capacity of the cement/waste products was measured in order to obtain information on their buffering capacity. Experimental results from chemical analysis of leachates led to a non ecotoxic character of cement/waste products Although the metallic ions were mobilized within the cement mattices, the organic matter did not allow the formation of monolithic forms and an efficient immobilization of phenolic compounds. Concerning the acid neutralization capacity, this parameter was shown to depend mainly on the quantity of cement, although a decrease in alkalinity was observed when the amount of water in the cement/waste products increased.

Accumulation of heavy metals by vegetables grown in mine wastes

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

Cobb, G.P.; Sands, K.; Waters, M.

2000-03-01

Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assessmore » metal content in the immediate plant environment. This analysis verified heterogeneous metal content of the mine wastes. The four plant species effectively accumulated and translocated lead, cadmium, arsenic, and zinc. Tomato and bean plants contained the four metals mainly in the roots and little was translocated to the fruits. Radish roots accumulated less metals compared to the leaves, whereas lettuce roots and leaves accumulated similar concentrations of the four metals. Lettuce leaves and radish roots accumulated significantly more metals than bean and tomato fruits. This accumulation pattern suggests that consumption of lettuce leaves or radish roots from plants grown in mine wastes would pose greater risks to humans and wildlife than would consumption of beans or tomatoes grown in the same area. The potential risk may be mitigated somewhat in humans, as vegetables grown in mine wastes exhibited stunted growth and chlorosis.« less

Cermets and method for making same

DOEpatents

Aaron, W. Scott; Kinser, Donald L.; Quinby, Thomas C.

1983-01-01

The present invention is directed to a method for making a wide variety of general-purpose cermets and for radioactive waste disposal from ceramic powders prepared from urea-dispersed solutions containing various metal values. The powders are formed into a compact and subjected to a rapid temperature increase in a reducing atmosphere. During this reduction, one or more of the more readily reducible oxides in the compact is reduced to a selected substoichiometric state at a temperature below the eutectic phase for that particular oxide or oxides and then raised to a temperature greater than the eutectic temperature to provide a liquid phase in the compact prior to the reduction of the liquid phase forming oxide to solid metal. This liquid phase forms at a temperature below the melting temperature of the metal and bonds together the remaining particulates in the cermet to form a solid polycrystalline cermet.

Evaluation of the nephrotoxicity of complex mixtures containing organics and metals: advantages and disadvantages of the use of real-world complex mixtures.

PubMed

Simmons, J E; Yang, R S; Berman, E

1995-02-01

As part of a multidisciplinary health effects study, the nephrotoxicity of complex industrial waste mixtures was assessed. Adult, male Fischer 344 rats were gavaged with samples of complex industrial waste and nephrotoxicity evaluated 24 hr later. Of the 10 tested samples, 4 produced increased absolute or relative kidney weight, or both, coupled with a statistically significant alteration in at least one of the measured serum parameters (urea nitrogen (BUN), creatinine (CREAT), and BUN/CREAT ratio). Although the waste samples had been analyzed for a number of organic chemicals and 7 of the 10 samples were analyzed also for 12 elemental metals and metalloids, their nephrotoxicity was not readily predicted from the partial chemical characterization data. Because the chemical form or speciation of the metals was unknown, it was not possible to estimate their contribution to the observed biological response. Various experimental approaches, including use of real-world complex mixtures, chemically defined synthetic mixtures, and simple mixtures, will be necessary to adequately determine the potential human health risk from exposure to complex chemical mixtures.

A dipeptide-based superhydrogel: Removal of toxic dyes and heavy metal ions from waste water.

PubMed

Nandi, Nibedita; Baral, Abhishek; Basu, Kingshuk; Roy, Subhasish; Banerjee, Arindam

2017-01-01

A short peptide-based molecule has been found to form a strong hydrogel at phosphate buffer solution of pH 7.46. The hydrogel has been characterized thoroughly using various techniques including field emission scanning electron microscopy (FE-SEM), wide angle powder X-ray diffraction (PXRD), and rheological analysis. It has been observed from FE-SEM images that entangled nanofiber network is responsible for gelation. Rheological investigation demonstrates that the self-assembly of this synthetic dipeptide results in the formation of mechanically strong hydrogel with storage modulus (G') around 10 4 Pa. This gel has been used for removing both cationic and anionic toxic organic dyes (Brilliant Blue, Congo red, Malachite Green, Rhodamine B) and metal ions (Co 2+ and Ni 2+ ) from waste water. Moreover, only a small amount of the gelator is required (less than 1 mg/mL) for preparation of this superhydrogel and even this hydrogel can be reused three times for dye/metal ion absorption. This signifies the importance of the hydrogel towards waste water management. © 2016 Wiley Periodicals, Inc.

LISREL Model Medical Solid Infectious Waste Hazardous Hospital Management In Medan City

NASA Astrophysics Data System (ADS)

Simarmata, Verawaty; Siahaan, Ungkap; Pandia, Setiaty; Mawengkang, Herman

2018-01-01

Hazardous and toxic waste resulting from activities at most hospitals contain various elements of medical solid waste ranging from heavy metals that have the nature of accumulative toxic which are harmful to human health. Medical waste in the form of gas, liquid or solid generally include the category or the nature of the hazard and toxicity waste. The operational in activities of the hospital aims to improve the health and well-being, but it also produces waste as an environmental pollutant waters, soil and gas. From the description of the background of the above in mind that the management of solid waste pollution control medical hospital, is one of the fundamental problems in the city of Medan and application supervision is the main business licensing and control alternatives in accordance with applicable regulations.

Metal solubilization from metal-containing solid materials by cyanogenic Chromobacterium violaceum.

PubMed

Faramarzi, Mohammad A; Stagars, Marion; Pensini, Enrico; Krebs, Walter; Brandl, Helmut

2004-09-30

Different cyanogenic bacterial strains (Chromobacterium violaceum, Pseudomonas fluorescens, Bacillus megaterium) were cultivated under cyanide-forming conditions in the presence of metal-containing solids such as nickel powder or electronic scrap. All microorganisms were able to form water-soluble metal cyanides, however, with different efficiencies. C. violaceum was able to mobilize nickel as tetracyanonickelate [Ni(CN)4(2-)] from fine-grained nickel powder. Gold was microbially solubilized as dicyanaoaurate [Au(CN)2-] from electronic waste. Additionally, cyanide-complexed copper was detected during biological treatment of shredded printed circuit boards scrap. Regarding the formation of tetracyanonickelate, C. violaceum was more effective than P. fluorescens or B. megaterium. Besides a few previous reports on gold solubilization from gold-containing ores or native gold by C. violaceum, the findings demonstrate for the first time the microbial mobilization of metals other than gold from solid materials and represent a novel type of microbial metal mobilization based on the ability of certain microbes to form HCN. The results might have the potential for industrial applications (biorecovery, bioremediation) regarding the treatment of metal-containing solids since metal cyanides can easily be separated by chromatographic means and be recovered by sorption onto activated carbon.

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

Bae, Wookeun; Shin, Eung Bai; Lee, Kil Chul

The potential hazard of landfill wastes was previously evaluated by examining the extraction procedures for individual waste, although various wastes were co-disposed of in actual landfills. This paper investigates the reduction of extraction-procedure toxicity by co-disposing various combinations of two wastes. When two wastes are mixed homogeneously, the extraction of heavy metals from the waste mixture is critically affected by the extract pH. Thus, co-disposal wastes will have a resultant pH between the pH values of its constituent. The lower the resultant pH, the lower the concentrations of heavy metals in the extract. When these wastes are extracted sequentially, themore » latter extracted waste has a stronger influence on the final concentration of heavy metals in the extract. Small-scale lysimeter experiments confirm that when heavy-metal-bearing leachates Generated from hazardous-waste lysimeters are passed through a nonhazardous-waste lysimeter filled with compost, briquette ash, or refuse-incineration ashes, the heavy-metal concentration in the final leachates decreases significantly. Thus, the heavy-metal leaching could be attenuated if a less extraction-procedure-toxic waste were placed at the bottom of a landfill. 3 refs., 4 figs., 5 tabs.« less

Getters for improved technetium containment in cementitious waste forms

DOE PAGES

Asmussen, R. Matthew; Pearce, Carolyn I.; Miller, Brian W.; ...

2017-07-26

A cementitious waste form, Cast Stone, is a possible candidate technology for the immobilization of low activity nuclear waste (LAW) at the Hanford site. This paper focuses on the addition of getter materials to Cast Stone that can sequester Tc from the LAW, and in turn, lower Tc release from the Cast Stone. Two getters which produce different products upon sequestering Tc from LAW were tested: Sn(II) apatite (Sn-A) that removes Tc as a Tc(IV)-oxide and potassium metal sulfide (KMS-2) that removes Tc as a Tc(IV)-sulfide species, allowing for a comparison of stability of the form of Tc upon enteringmore » the waste form. The Cast Stone with KMS-2 getter had the best performance with addition equivalent to ~0.08 wt% of the total waste form mass. The observed diffusion (D obs) of Tc decreased from 4.6 ± 0.2 × 10 -12 cm 2/s for Cast Stone that did not contain a getter to 5.4 ± 0.4 × 10 -13 cm 2/s for KMS-2 containing Cast Stone. Finally, it was found that Tc-sulfide species are more stable against re-oxidation within getter containing Cast Stone compared with Tc-oxide and is the origin of the decrease in Tc D obs when using the KMS-2.« less

Getters for improved technetium containment in cementitious waste forms.

PubMed

Asmussen, R Matthew; Pearce, Carolyn I; Miller, Brian W; Lawter, Amanda R; Neeway, James J; Lukens, Wayne W; Bowden, Mark E; Miller, Micah A; Buck, Edgar C; Serne, R Jeffery; Qafoku, Nikolla P

2018-01-05

A cementitious waste form, Cast Stone, is a possible candidate technology for the immobilization of low activity nuclear waste (LAW) at the Hanford site. This work focuses on the addition of getter materials to Cast Stone that can sequester Tc from the LAW, and in turn, lower Tc release from the Cast Stone. Two getters which produce different products upon sequestering Tc from LAW were tested: Sn(II) apatite (Sn-A) that removes Tc as a Tc(IV)-oxide and potassium metal sulfide (KMS-2) that removes Tc as a Tc(IV)-sulfide species, allowing for a comparison of stability of the form of Tc upon entering the waste form. The Cast Stone with KMS-2 getter had the best performance with addition equivalent to ∼0.08wt% of the total waste form mass. The observed diffusion (D obs ) of Tc decreased from 4.6±0.2×10 -12 cm 2 /s for Cast Stone that did not contain a getter to 5.4±0.4×10 -13 cm 2 /s for KMS-2 containing Cast Stone. It was found that Tc-sulfide species are more stable against re-oxidation within getter containing Cast Stone compared with Tc-oxide and is the origin of the decrease in Tc D obs when using the KMS-2. Copyright © 2017 Elsevier B.V. All rights reserved.

Glass corrosion in natural environments

NASA Technical Reports Server (NTRS)

Thorpe, Arthur N.; Barkatt, Aaron

1992-01-01

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

Process for the displacement of cyanide ions from metal-cyanide complexes

DOEpatents

Smith, Barbara F.; Robinson, Thomas W.

1997-01-01

The present invention relates to water-soluble polymers and the use of such water-soluble polymers in a process for the displacement of the cyanide ions from the metal ions within metal-cyanide complexes. The process waste streams can include metal-cyanide containing electroplating waste streams, mining leach waste streams, mineral processing waste streams, and related metal-cyanide containing waste streams. The metal ions of interest are metals that give very strong complexes with cyanide, mostly iron, nickel, and copper. The physical separation of the water-soluble polymer-metal complex from the cyanide ions can be accomplished through the use of ultrafiltration. Once the metal-cyanide complex is disrupted, the freed cyanide ions can be recovered for reuse or destroyed using available oxidative processes rendering the cyanide nonhazardous. The metal ions are released from the polymer, using dilute acid, metal ion oxidation state adjustment, or competing chelating agents, and collected and recovered or disposed of by appropriate waste management techniques. The water-soluble polymer can then be recycled. Preferred water-soluble polymers include polyethyleneimine and polyethyleneimine having a catechol or hydroxamate group.

Flow analysis of metals in a municipal solid waste management system.

PubMed

Jung, C H; Matsuto, T; Tanaka, N

2006-01-01

This study aimed to identify the metal flow in a municipal solid waste (MSW) management system. Outputs of a resource recovery facility, refuse derived fuel (RDF) production facility, carbonization facility, plastics liquefaction facility, composting facility, and bio-gasification facility were analyzed for metal content and leaching concentration. In terms of metal content, bulky and incombustible waste had the highest values. Char from a carbonization facility, which treats household waste, had a higher metal content than MSW incinerator bottom ash. A leaching test revealed that Cd and Pb in char and Pb in RDF production residue exceeded the Japanese regulatory criteria for landfilling, so special attention should be paid to final disposal of these substances. By multiplying metal content and the generation rate of outputs, the metal content of input waste to each facility was estimated. For most metals except Cr, the total contribution ratio of paper/textile/plastics, bulky waste, and incombustible waste was over 80%. Approximately 30% of Cr originated from plastic packaging. Finally, several MSW management scenarios showed that most metals are transferred to landfills and the leaching potential of metals to the environment is quite small.

Flow analysis of metals in a municipal solid waste management system

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

Jung, C.H.; Matsuto, T.; Tanaka, N.

2006-07-01

This study aimed to identify the metal flow in a municipal solid waste (MSW) management system. Outputs of a resource recovery facility, refuse derived fuel (RDF) production facility, carbonization facility, plastics liquefaction facility, composting facility, and bio-gasification facility were analyzed for metal content and leaching concentration. In terms of metal content, bulky and incombustible waste had the highest values. Char from a carbonization facility, which treats household waste, had a higher metal content than MSW incinerator bottom ash. A leaching test revealed that Cd and Pb in char and Pb in RDF production residue exceeded the Japanese regulatory criteria formore » landfilling, so special attention should be paid to final disposal of these substances. By multiplying metal content and the generation rate of outputs, the metal content of input waste to each facility was estimated. For most metals except Cr, the total contribution ratio of paper/textile/plastics, bulky waste, and incombustible waste was over 80%. Approximately 30% of Cr originated from plastic packaging. Finally, several MSW management scenarios showed that most metals are transferred to landfills and the leaching potential of metals to the environment is quite small.« less

Innovative methodology for electrical conductivity measurements and metal partition in biosolid pellets

NASA Astrophysics Data System (ADS)

Jordan, Manuel Miguel; Rincón-Mora, Beatriz; Belén Almendro-Candel, María; Navarro-Pedreño, José; Gómez-Lucas, Ignacio; Bech, Jaume

2017-04-01

Use of biosolids to improve the nutrient content in a soil is a common practice. The obligation to restore abandoned mine and the correct application of biosolids is guaranteed by the legislation on waste management, biosolids and soil conservation (Jordán et al. 2008). The present research was conducted to determine electrical conductivity in dry wastes (pellets) using a innovative methodology (Camilla and Jordán, 2009). On the other hand, the present study was designed to examine the distribution of selected heavy metals in biosolid pellets, and also to relate the distribution patterns of these metals. In this context, heavy metal concentrations were studied in biosolid pellets under different pressures. Electrical conductivity measurements were taken in biosolid pellets under pressures on the order of 50 to 150 MPa and with currents of 10-15 A. Measurements of electrical conductivity and heavy metal content for different areas (H1, H2, and H3) were taken. Total content of metals was determined following microwave digestion and analysed by ICP/MS. Triplicate portions were weighed in polycarbonate centrifuge tubes and sequentially extracted. The distribution of chemical forms of Cd, Ni, Cr, and Pb in the biosolids was studied using a sequential extraction procedure that fractionates the metal into soluble-exchangeable, specifically sorbed-carbonate bound, oxidizable, reducible, and residual forms. The residual, reducible, and carbonate-sorbed forms were dominant. Higher Cr and Ni content were detected in pellets made with biosolids from the H3. The highest Cd and Ni values were detected in the H2. The trends of the conductivity curves were similar for the sludge from the isolation surface (H1) and for the mesophilous area (H2). In the case of the thermophilous area (H3), the electrical conductivity showed extremely high values. This behaviour was similar in the case of the Cr and Ni content. However, in the case of Cd and Pb, the highest values were detected in the H2. This experiment could be useful for establishing a general rule for taking measurements of electrical conductivity and heavy metals in biosolid pellets and other types of dry wastes. References Camilla S, Jordán MM (2009) Electrical conductivity measurements in sewage sludge pellets: innovative techniques for environmental management. J Hazard Mater 168:1260-1263 Jordán, MM, Rincón-Mora, B; Almendro, MB (2015). Heavy metal distribution and electrical conductivity measurements in biosolid pellets. J, Soils and Sediments, 16 1176-118

Leachability of heavy metals in geopolymer-based materials synthesized from red mud and rice husk ash

NASA Astrophysics Data System (ADS)

Nguyen, Hoc Thang; Pham, Vo Thi Ha Quyen; Dang, Thanh Phong; Dao, Thanh Khe

2018-04-01

Red mud is an industrial waste generated during aluminum production from bauxite whereas rice husk ash is an agricultural waste from burning of rice husk that could cause negative impact on the environment if not properly managed. This study demonstrates the utilization of red mud in combination with rice husk ash to form a geopolymer-based material which can be used as bricks or replacement for traditional cement materials. The focus of this study is on the leachability of heavy metals in the raw materials and the geopolymer as this would be significant in assessing the environmental impact of the product. Leachability of metals such as Cu, Zn, Cd, Pb, Fe, and Cr was evaluated based on European (EN 124572-2 EU CEN TC292/ CEN TC 308) standard with pH value 7. Results indicate that the leachability of these metals in the geopolymer matrix is lower than that of the raw materials.

A review of metal recovery from spent petroleum catalysts and ash.

PubMed

Akcil, Ata; Vegliò, Francesco; Ferella, Francesco; Okudan, Mediha Demet; Tuncuk, Aysenur

2015-11-01

With the increase in environmental awareness, the disposal of any form of hazardous waste has become a great concern for the industrial sector. Spent catalysts contribute to a significant amount of the solid waste generated by the petrochemical and petroleum refining industry. Hydro-cracking and hydrodesulfurization (HDS) catalysts are extensively used in the petroleum refining and petrochemical industries. The catalysts used in the refining processes lose their effectiveness over time. When the activity of catalysts decline below the acceptable level, they are usually regenerated and reused but regeneration is not possible every time. Recycling of some industrial waste containing base metals (such as V, Ni, Co, Mo) is estimated as an economical opportunity in the exploitation of these wastes. Alkali roasted catalysts can be leached in water to get the Mo and V in solution (in which temperature plays an important role during leaching). Several techniques are possible to separate the different metals, among those selective precipitation and solvent extraction are the most used. Pyrometallurgical treatment and bio-hydrometallurgical leaching were also proposed in the scientific literature but up to now they did not have any industrial application. An overview on patented and commercial processes was also presented. Copyright © 2015 Elsevier Ltd. All rights reserved.

Basic repository environmental assessment design basis, Lavender Canyon site

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

Not Available

1988-01-01

This study examines the engineering factors and costs associated with the construction, operation, and decommissioning of a high-level nuclear waste repository in salt in the Paradox Basin in Lavender Canyon, Utah. The study assumes a repository capacity of 36,000 metric tons of heavy metal (MTHM) of unreprocessed spent fuel and 36,000 MTHM of commercial high-level reprocessing waste, along with 7020 canisters of defense high-level reprocessing waste and associated quantities of remote- and contact-handled transuranic waste (TRU). With the exception of TRU, all the waste forms are placed in 300- to 1000-year-life carbon-steel waste packages in a collocated waste handling andmore » packaging facility (WHPF), which is also described. The construction, operation, and decommissioning of the proposed repository is estimated to cost approximately $5.51 billion. Costs include those for the collocated WHPP, engineering, and contingency, but exclude waste form assembly and shipment to the site and waste package fabrication and shipment to the site. These costs reflect the relative average wage rates of the region and the relatively sound nature of the salt at this site. Construction would require an estimated 7.75 years. Engineering factors and costs are not strongly influenced by environmental considerations. 51 refs., 24 figs., 20 tabs.« less

Development studies of a novel wet oxidation process

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

Rogers, T.W.; Dhooge, P.M.

1995-12-01

Many DOE waste streams and remediates contain complex and variable mixtures of organic compounds, toxic metals, and radionuclides. These materials are often dispersed in organic or inorganic matrices, such as personal protective equipment, various sludges, soils, and water. Incineration and similar combustive processes do not appear to be viable options for treatment of these waste streams due to various considerations. There is a need for non-combustion processes with a wide application range to treat the large majority of these waste forms. The non-combustion process should also be safe, effective, cost-competitive, permit-able, and preferrably mobile. This paper describes the DETOX processmore » of organic waste oxidation.« less

Evaluation of final waste forms and recommendations for baseline alternatives to group and glass

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

Bleier, A.

1997-09-01

An assessment of final waste forms was made as part of the Federal Facilities Compliance Agreement/Development, Demonstration, Testing, and Evaluation (FFCA/DDT&E) Program because supplemental waste-form technologies are needed for the hazardous, radioactive, and mixed wastes of concern to the Department of Energy and the problematic wastes on the Oak Ridge Reservation. The principal objective was to identify a primary waste-form candidate as an alternative to grout (cement) and glass. The effort principally comprised a literature search, the goal of which was to establish a knowledge base regarding four areas: (1) the waste-form technologies based on grout and glass, (2) candidatemore » alternatives, (3) the wastes that need to be immobilized, and (4) the technical and regulatory constraints on the waste-from technologies. This report serves, in part, to meet this goal. Six families of materials emerged as relevant; inorganic, organic, vitrified, devitrified, ceramic, and metallic matrices. Multiple members of each family were assessed, emphasizing the materials-oriented factors and accounting for the fact that the two most prevalent types of wastes for the FFCA/DDT&E Program are aqueous liquids and inorganic sludges and solids. Presently, no individual matrix is sufficiently developed to permit its immediate implementation as a baseline alternative. Three thermoplastic materials, sulfur-polymer cement (inorganic), bitumen (organic), and polyethylene (organic), are the most technologically developed candidates. Each warrants further study, emphasizing the engineering and economic factors, but each also has limitations that regulate it to a status of short-term alternative. The crystallinity and flexible processing of sulfur provide sulfur-polymer cement with the highest potential for short-term success via encapsulation. Long-term immobilization demands chemical stabilization, which the thermoplastic matrices do not offer. Among the properties of the remaining candidates, those of glass-ceramics (devitrified matrices) represent the best compromise for meeting the probable stricter disposal requirements in the future.« less

Thermal treatment of toxic metals of industrial hazardous wastes with fly ash and clay.

PubMed

Singh, I B; Chaturvedi, K; Morchhale, R K; Yegneswaran, A H

2007-03-06

Waste generated from galvanizing and metal finishing processes is considered to be a hazardous due to the presence of toxic metals like Pb, Cu, Cr, Zn, etc. Thermal treatment of such types of wastes in the presence of clay and fly ash can immobilizes their toxic metals to a maximum level. After treatment solidified mass can be utilized in construction or disposed off through land fillings without susceptibility of re-mobilization of toxic metals. In the present investigation locally available clay and fly ash of particular thermal power plant were used as additives for thermal treatment of both of the wastes in their different proportions at 850, 900 and 950 degrees C. Observed results indicated that heating temperature to be a key factor in the immobilization of toxic metals of the waste. It was noticed that the leachability of metals of the waste reduces to a negligible level after heating at 950 degrees C. Thermally treated solidified specimen of 10% waste and remaining clay have shown comparatively a higher compressive strength than clay fired bricks used in building construction. Though, thermally heated specimens made of galvanizing waste have shown much better strength than specimen made of metal finishing waste. The lechability of toxic metals like Cr, Cu, Pb and Zn became far below from their regulatory threshold after heating at 950 degrees C. Addition of fly ash did not show any improvement either in engineering property or in leachability of metals from the solidified mass. X-ray diffraction (XRD) analysis of the solidified product confirmed the presence of mixed phases of oxides of metals.

Synergistic effect of biogenic Fe3+ coupled to S° oxidation on simultaneous bioleaching of Cu, Co, Zn and As from hazardous Pyrite Ash Waste.

PubMed

Panda, Sandeep; Akcil, Ata; Mishra, Srabani; Erust, Ceren

2017-03-05

Pyrite ash, a waste by-product formed during roasting of pyrite ores, is a good source of valuable metals. The waste is associated with several environmental issues due to its dumping in sea and/or land filling. Although several other management practices are available for its utilization, the waste still awaits and calls for an eco-friendly biotechnological application for metal recovery. In the present study, chemolithotrophic meso-acidophilic iron and sulphur oxidisers were evaluated for the first time towards simultaneous mutli-metal recovery from pyrite ash. XRD and XRF analysis indicated higher amount of Hematite (Fe 2 O 3 ) in the sample. ICP-OES analysis indicated concentrations of Cu>Zn>Co>As that were considered for bioleaching. Optimization studies indicated Cu - 95%, Co - 97%, Zn - 78% and As - 60% recovery within 8days at 10% pulp density, pH - 1.75, 10% (v/v) inoculum and 9g/L Fe 2+ . The productivity of the bioleaching system was found to be Cu - 1696ppm/d (12% dissolution/d), Co - 338ppm/d (12.2% dissolution/d), Zn k 576ppm/d (9.8% dissolution/d) and As - 75ppm/d (7.5% dissolution/d). Synergistic actions for Fe 2+ - S° oxidation by iron and sulphur oxidisers were identified as the key drivers for enhanced metal dissolution from pyrite ash sample. Copyright © 2016 Elsevier B.V. All rights reserved.

Prospects for Fungal Bioremediation of Acidic Radioactive Waste Sites: Characterization and Genome Sequence of Rhodotorula taiwanensis MD1149.

PubMed

Tkavc, Rok; Matrosova, Vera Y; Grichenko, Olga E; Gostinčar, Cene; Volpe, Robert P; Klimenkova, Polina; Gaidamakova, Elena K; Zhou, Carol E; Stewart, Benjamin J; Lyman, Mathew G; Malfatti, Stephanie A; Rubinfeld, Bonnee; Courtot, Melanie; Singh, Jatinder; Dalgard, Clifton L; Hamilton, Theron; Frey, Kenneth G; Gunde-Cimerman, Nina; Dugan, Lawrence; Daly, Michael J

2017-01-01

Highly concentrated radionuclide waste produced during the Cold War era is stored at US Department of Energy (DOE) production sites. This radioactive waste was often highly acidic and mixed with heavy metals, and has been leaking into the environment since the 1950s. Because of the danger and expense of cleanup of such radioactive sites by physicochemical processes, in situ bioremediation methods are being developed for cleanup of contaminated ground and groundwater. To date, the most developed microbial treatment proposed for high-level radioactive sites employs the radiation-resistant bacterium Deinococcus radiodurans . However, the use of Deinococcus spp. and other bacteria is limited by their sensitivity to low pH. We report the characterization of 27 diverse environmental yeasts for their resistance to ionizing radiation (chronic and acute), heavy metals, pH minima, temperature maxima and optima, and their ability to form biofilms. Remarkably, many yeasts are extremely resistant to ionizing radiation and heavy metals. They also excrete carboxylic acids and are exceptionally tolerant to low pH. A special focus is placed on Rhodotorula taiwanensis MD1149, which was the most resistant to acid and gamma radiation. MD1149 is capable of growing under 66 Gy/h at pH 2.3 and in the presence of high concentrations of mercury and chromium compounds, and forming biofilms under high-level chronic radiation and low pH. We present the whole genome sequence and annotation of R. taiwanensis strain MD1149, with a comparison to other Rhodotorula species. This survey elevates yeasts to the frontier of biology's most radiation-resistant representatives, presenting a strong rationale for a role of fungi in bioremediation of acidic radioactive waste sites.

Prospects for Fungal Bioremediation of Acidic Radioactive Waste Sites: Characterization and Genome Sequence of Rhodotorula taiwanensis MD1149

PubMed Central

Tkavc, Rok; Matrosova, Vera Y.; Grichenko, Olga E.; Gostinčar, Cene; Volpe, Robert P.; Klimenkova, Polina; Gaidamakova, Elena K.; Zhou, Carol E.; Stewart, Benjamin J.; Lyman, Mathew G.; Malfatti, Stephanie A.; Rubinfeld, Bonnee; Courtot, Melanie; Singh, Jatinder; Dalgard, Clifton L.; Hamilton, Theron; Frey, Kenneth G.; Gunde-Cimerman, Nina; Dugan, Lawrence; Daly, Michael J.

2018-01-01

Highly concentrated radionuclide waste produced during the Cold War era is stored at US Department of Energy (DOE) production sites. This radioactive waste was often highly acidic and mixed with heavy metals, and has been leaking into the environment since the 1950s. Because of the danger and expense of cleanup of such radioactive sites by physicochemical processes, in situ bioremediation methods are being developed for cleanup of contaminated ground and groundwater. To date, the most developed microbial treatment proposed for high-level radioactive sites employs the radiation-resistant bacterium Deinococcus radiodurans. However, the use of Deinococcus spp. and other bacteria is limited by their sensitivity to low pH. We report the characterization of 27 diverse environmental yeasts for their resistance to ionizing radiation (chronic and acute), heavy metals, pH minima, temperature maxima and optima, and their ability to form biofilms. Remarkably, many yeasts are extremely resistant to ionizing radiation and heavy metals. They also excrete carboxylic acids and are exceptionally tolerant to low pH. A special focus is placed on Rhodotorula taiwanensis MD1149, which was the most resistant to acid and gamma radiation. MD1149 is capable of growing under 66 Gy/h at pH 2.3 and in the presence of high concentrations of mercury and chromium compounds, and forming biofilms under high-level chronic radiation and low pH. We present the whole genome sequence and annotation of R. taiwanensis strain MD1149, with a comparison to other Rhodotorula species. This survey elevates yeasts to the frontier of biology's most radiation-resistant representatives, presenting a strong rationale for a role of fungi in bioremediation of acidic radioactive waste sites. PMID:29375494

The presence of zinc in Swedish waste fuels.

PubMed

Jones, Frida; Bisaillon, Mattias; Lindberg, Daniel; Hupa, Mikko

2013-12-01

Zinc (Zn) is a chemical element that has gained more attention lately owing to its possibility to form corrosive deposits in large boilers, such as Waste-to-Energy plants. Zn enters the boilers in many different forms and particularly in waste, the amount of Zn is hard to determine due to both the heterogeneity of waste in general but also due to the fact that little is yet published specifically about the Zn levels in waste. This study aimed to determine the Zn in Swedish waste fuels by taking regular samples from seven different and geographically separate waste combustion plants over a 12-month period. The analysis shows that there is a relation between the municipal solid waste (MSW) content and the Zn-content; high MSW-content gives lower Zn-content. This means that waste combustion plants with a higher share of industrial and commercial waste and/or building and demolition waste would have a higher share of Zn in the fuel. The study also shows that in Sweden, the geographic location of the plant does not have any effect on the Zn-content. Furthermore, it is concluded that different seasons appear not to affect the Zn concentrations significantly. In some plants there was a clear correlation between the Zn-content and the content of other trace metals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Metallic elements fractionation in municipal solid waste incineration residues

NASA Astrophysics Data System (ADS)

Kowalski, Piotr R.; Kasina, Monika; Michalik, Marek

2016-04-01

Municipal solid waste incineration (MSWI) residues are represented by three main materials: bottom ash, fly ash and air pollution control (APC) residues. Among them ˜80 wt% is bottom ash. All of that materials are products of high temperature (>1000° C) treatment of waste. Incineration process allows to obtain significant reduction of waste mass (up to 70%) and volume (up to 90%) what is commonly used in waste management to reduce the amount need to be landfilled or managed in other way. Incineration promote accumulation non-combustible fraction of waste, which part are metallic elements. That type of concentration is object of concerns about the incineration residues impact on the environment and also gives the possibility of attempts to recover them. Metallic elements are not equally distributed among the materials. Several factors influence the process: melting points, volatility and place and forms of metallic occurrence in the incinerated waste. To investigate metallic elements distribution in MSWI residues samples from one of the biggest MSW incineration plant in Poland were collected in 2015. Chemical analysis with emphasis on the metallic elements content were performed using inductively coupled plasma optical emission (ICP-OES) and mass spectrometry (ICP-MS). The bottom ash was a SiO2-CaO-Al2O3-Fe2O3-Na2O rich material, whereas fly ash and APC residues were mostly composed of CaO and SiO2. All of the materials were rich in amorphous phase occurring together with various, mostly silicate crystalline phases. In a mass of bottom ash 11 wt% were metallic elements but also in ashes 8.5 wt% (fly ash) and ˜4.5 wt% (APC residues) of them were present. Among the metallic elements equal distribution between bottom and fly ash was observed for Al (˜3.85 wt%), Mn (770 ppm) and Ni (˜65 ppm). In bottom ash Fe (5.5 wt%), Cr (590 ppm) and Cu (1250 ppm) were concentrated. These values in comparison to fly ash were 5-fold higher for Fe, 3-fold for Cu and 1.5-fold for Cr. In comparison to bottom ash, in fly ash 10-fold more Zn was present (8070 ppm), 4-fold more Sn (540 ppm) and also 2-fold more Ti (1.1 wt%), Pb (460 ppm) and Sn (540 ppm). Although APC residue is the material produced in the smallest quantities, in its composition some high concentrations of metallic elements were also present. Contents of Zn (>1 wt%), Pb (2560 ppm) and Sn (875 ppm) were much higher than in bottom and fly ash. Obtained results confirmed that fractionation of elements occurs during the municipal waste incineration and further detailed study of the residues may allow better understanding of the process. Acknowledgment: Research was funded by Polish National Science Centre (NCN). Scientific grant No. UMO-2014/15/B/ST10/04171.

Thermal and hydrometallurgical recovery methods of heavy metals from municipal solid waste fly ash.

PubMed

Kuboňová, L; Langová, Š; Nowak, B; Winter, F

2013-11-01

Heavy metals in fly ash from municipal solid waste incinerators are present in high concentrations. Therefore fly ash must be treated as a hazardous material. On the other hand, it may be a potential source of heavy metals. Zinc, lead, cadmium, and copper can be relatively easily removed during the thermal treatment of fly ash, e.g. in the form of chlorides. In return, wet extraction methods could provide promising results for these elements including chromium and nickel. The aim of this study was to investigate and compare thermal and hydrometallurgical treatment of municipal solid waste fly ash. Thermal treatment of fly ash was performed in a rotary reactor at temperatures between 950 and 1050°C and in a muffle oven at temperatures from 500 to 1200°C. The removal more than 90% was reached by easy volatile heavy metals such as cadmium and lead and also by copper, however at higher temperature in the muffle oven. The alkaline (sodium hydroxide) and acid (sulphuric acid) leaching of the fly ash was carried out while the influence of temperature, time, concentration, and liquid/solid ratio were investigated. The combination of alkaline-acidic leaching enhanced the removal of, namely, zinc, chromium and nickel. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Study on the Heat Flow Characteristics of IRSS

NASA Astrophysics Data System (ADS)

Cho, Yong-Jin; Ko, Dae-Eun

2017-11-01

The infrared signatures emitted from the hot waste gas generated by the combustion engine and generator of a naval ship and from the metal surface around the funnel are the targets of the enemy threatening weapon system, thereby reducing the survivability of the ship. Such infrared signatures are reduced by installing an infrared signature suppression system (IRSS) in the naval ship. An IRSS consists of three parts: an eductor that creates a turbulent flow in the waste gas, a mixing tube that mixes the waste gas with the ambient air, and a diffuser that forms an air film using the pressure difference between the waste gas and the outside air. This study analyzed the test model of the IRSS developed by an advanced company and, based on this, conducted heat flow analyses as a basic study to improve the performance of the IRSS. The results were compared and analyzed considering various turbulence models. As a result, the temperatures and velocities of the waste gas at the eductor inlet and the diffuser outlet as well as the temperature of the diffuser metal surface were obtained. It was confirmed that these results were in good agreement with the measurement results of the model test.

Metallurgical recovery of metals from electronic waste: a review.

PubMed

Cui, Jirang; Zhang, Lifeng

2008-10-30

Waste electric and electronic equipment, or electronic waste, has been taken into consideration not only by the government but also by the public due to their hazardous material contents. In the detailed literature survey, value distributions for different electronic waste samples were calculated. It is showed that the major economic driver for recycling of electronic waste is from the recovery of precious metals. The state of the art in recovery of precious metals from electronic waste by pyrometallurgical processing, hydrometallurgical processing, and biometallurgical processing are highlighted in the paper. Pyrometallurgical processing has been a traditional technology for recovery of precious metals from waste electronic equipment. However, state-of-the-art smelters are highly depended on investments. Recent research on recovery of energy from PC waste gives an example for using plastics in this waste stream. It indicates that thermal processing provides a feasible approach for recovery of energy from electronic waste if a comprehensive emission control system is installed. In the last decade, attentions have been removed from pyrometallurgical process to hydrometallurgical process for recovery of metals from electronic waste. In the paper, hydrometallurgical processing techniques including cyanide leaching, halide leaching, thiourea leaching, and thiosulfate leaching of precious metals are detailed. In order to develop an environmentally friendly technique for recovery of precious metals from electronic scrap, a critical comparison of main leaching methods is analyzed for both economic feasibility and environmental impact. It is believed that biotechnology has been one of the most promising technologies in metallurgical processing. Bioleaching has been used for recovery of precious metals and copper from ores for many years. However, limited research was carried out on the bioleaching of metals from electronic waste. In the review, initial researches on the topic are presented. In addition, mechanisms and models of biosorption of precious metal ions from solutions are discussed.

Informal E-waste recycling in developing countries: review of metal(loid)s pollution, environmental impacts and transport pathways.

PubMed

Ackah, Michael

2017-11-01

Crude or primitive recycling practices are often adopted in material resource recovery from E-waste in developing nations. Significant human health and environmental impacts may occur because of such practices. Literature on metal(loid)s pollution during E-waste processing is fragmented. Here, I review the health and environmental impacts of E-waste recycling operations and transport pathways of metal(loid)s, dispersed during operations. This paper is organised into five sections. Section 1 relates to the background of global E-waste generation and legal/illegal trade, citing specific cases from Ghana and other developing nations. Section 2 provides a brief information on sources of metal(loid)s in E-waste. Section 3 describes characteristics of informal E-waste recycling operations in developing nations. Section 4 examines the health and environmental impacts in E-waste recycling while section 5 evaluates major transport pathways of metal(loid)s contaminants.

Fiber reinforced concrete: An advanced technology for LL/ML radwaste conditioning and disposal

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

Tchemitcheff, E.; Verdier, A.

Radioactive waste immobilization is an integral part of operations in nuclear facilities. The goal of immobilization is to contain radioactive materials in a waste form which can maintain its integrity over very long periods of time, thus effectively isolating the materials from the environment and hence from the public. This is true regardless of the activity of the waste, including low-, and medium-level waste (LLW, MLW). A multiple-year research effort by Cogema culminated in the development of a new process to immobilize nuclear waste in concrete containers reinforced with metal fibers. The fiber concrete containers satisfy all French safety requirementsmore » relating to waste immobilization and disposal, and have been certified by ANDRA, the national radioactive waste management agency. The fiber concrete containers have been fabricated on a production scale since July 1990 by Sogefibre, a jointly-owned subsidiary of SGN and Compagnie Generale des Eaux.« less

Recycling of spent lithium-ion battery with polyvinyl chloride by mechanochemical process.

PubMed

Wang, Meng-Meng; Zhang, Cong-Cong; Zhang, Fu-Shen

2017-09-01

In the present study, cathode materials (C/LiCoO 2 ) of spent lithium-ion batteries (LIBs) and waste polyvinyl chloride (PVC) were co-processed via an innovative mechanochemical method, i.e. LiCoO 2 /PVC/Fe was co-grinded followed by water-leaching. This procedure generated recoverable LiCl from Li by the dechlorination of PVC and also generated magnetic CoFe 4 O 6 from Co. The effects of different additives (e.g. alkali metals, non-metal oxides, and zero-valent metals) on (i) the conversion rates of Li and Co and (ii) the dechlorination rate of PVC were investigated, and the reaction mechanisms were explored. It was found that the chlorine atoms in PVC were mechanochemically transformed into chloride ions that bound to the Li in LiCoO 2 to form LiCl. This resulted in reorganization of the Co and Fe crystals to form the magnetic material CoFe 4 O 6 . This study provides a more environmentally-friendly, economical, and straightforward approach for the recycling of spent LIBs and waste PVC compared to traditional processes. Copyright © 2017. Published by Elsevier Ltd.

Economic aspects of metals recover

NASA Astrophysics Data System (ADS)

Wieczorek, Daria; Kwaśniewska, Dobrawa

2018-03-01

One of the modern economy models is circular economy in which wastes should be considered as resource and used in an efficient and sustainable way. This also concerns to metals included in scraps. However, the need for metal recovery from waste is not only the result of the latest economic trends but also the result of large and constantly changing demand for metals. Shrinking natural sources of metals, concentrations of ores in small number of countries in the world and resulting from this dependence on import, geopolitical situation, new technologies demands are only a few most important determinants that have been changing the structure of the metal market over years. In this chapter, authors focused on the presentation of economic aspects of metal recovery from various sources. The chapter presents the characteristic of metal market elements (supply, demand and price) and changes that took place over decades, underlining the structure of precious and highly desirable metal market elements. Balance between the demand and supply ensures price stability and rationalizes inflation. However, growing demand on many means that secure supply chains, such as recycling and material recovery, are essential to ensure continuity in the supply chain and guarantee unrestricted technological progress and innovation. The data included in this chapter presents also the concentration of different metals and group of metals in wastes pointing that recycling of waste can become one of the possibilities of acquiring missing and critical metals. Metal-laden wastes include a few groups: waste electrical and electronic equipments, catalysts of different application, introduced on chemical, petrochemical or automotive market, galvanic wastes and wastewaters. The profitability assessment of recycling processes is very complicated. Nevertheless cited data shows that profitability of recovery depends on the metal analyzed and the type of waste. It must be underline that an optimized management of wastes is of a great importance for the global economy and allow achieving not only economic but also environmental and social benefits.

Concentration of precious metals during their recovery from electronic waste.

PubMed

Cayumil, R; Khanna, R; Rajarao, R; Mukherjee, P S; Sahajwalla, V

2016-11-01

The rapid growth of electronic devices, their subsequent obsolescence and disposal has resulted in electronic waste (e-waste) being one of the fastest increasing waste streams worldwide. The main component of e-waste is printed circuit boards (PCBs), which contain substantial quantities of precious metals in concentrations significantly higher than those typically found in corresponding ores. The high value and limited reserves of minerals containing these metals makes urban mining of precious metals very attractive. This article is focused on the concentration and recovery of precious metals during pyro-metallurgical recycling of waste PCBs. High temperature pyrolysis was carried out for ten minutes in a horizontal tube furnace in the temperature range 800-1350°C under Argon gas flowing at 1L/min. These temperatures were chosen to lie below and above the melting point (1084.87°C) of copper, the main metal in PCBs, to study the influence of its physical state on the recovery of precious metals. The heat treatment of waste PCBs resulted in two different types of solid products, namely a carbonaceous non-metallic fraction (NMFs) and metallic products, composed of copper rich foils and/or droplets and tin-lead rich droplets and some wires. Significant proportions of Ag, Au, Pd and Pt were found concentrated within two types of metallic phases, with very limited quantities retained by the NMFs. This process was successful in concentrating several precious metals such as Ag, Au, Pd and Pt in a small volume fraction, and reduced volumes for further processing/refinement by up to 75%. The amounts of secondary wastes produced were also minimised to a great extent. The generation of precious metals rich metallic phases demonstrates high temperature pyrolysis as a viable approach towards the recovery of precious metals from e-waste. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mass, energy and material balances of SRF production process. Part 3: solid recovered fuel produced from municipal solid waste.

PubMed

Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

2015-02-01

This is the third and final part of the three-part article written to describe the mass, energy and material balances of the solid recovered fuel production process produced from various types of waste streams through mechanical treatment. This article focused the production of solid recovered fuel from municipal solid waste. The stream of municipal solid waste used here as an input waste material to produce solid recovered fuel is energy waste collected from households of municipality. This article presents the mass, energy and material balances of the solid recovered fuel production process. These balances are based on the proximate as well as the ultimate analysis and the composition determination of various streams of material produced in a solid recovered fuel production plant. All the process streams are sampled and treated according to CEN standard methods for solid recovered fuel. The results of the mass balance of the solid recovered fuel production process showed that 72% of the input waste material was recovered in the form of solid recovered fuel; 2.6% as ferrous metal, 0.4% as non-ferrous metal, 11% was sorted as rejects material, 12% as fine faction and 2% as heavy fraction. The energy balance of the solid recovered fuel production process showed that 86% of the total input energy content of input waste material was recovered in the form of solid recovered fuel. The remaining percentage (14%) of the input energy was split into the streams of reject material, fine fraction and heavy fraction. The material balances of this process showed that mass fraction of paper and cardboard, plastic (soft) and wood recovered in the solid recovered fuel stream was 88%, 85% and 90%, respectively, of their input mass. A high mass fraction of rubber material, plastic (PVC-plastic) and inert (stone/rock and glass particles) was found in the reject material stream. © The Author(s) 2014.

Retrieval of Au, Ag, Cu precious metals coupled with electric energy production via an unconventional coupled redox fuel cell reactor.

PubMed

Zhang, Hui-Min; Fan, Zheng; Xu, Wei; Feng, Xiao; Wu, Zu-Cheng

2017-09-15

The recovery of heavy metals from aqueous solutions or e-wastes is of upmost importance. Retrieval of Au, Ag, and Cu with electricity generation through building an ethanol-metal coupled redox fuel cells (CRFCs) is demonstrated. The cell was uniquely assembled on PdNi/C anode the electro-oxidation of ethanol takes place to give electrons and then go through the external circuit reducing metal ions to metallic on the cathode, metals are recovered. Taking an example of removal of 100mgL -1 gold in 0.5M HAc-NaAc buffer solution as the catholyte, 2.0M ethanol in 1.0M alkaline solution as the anolyte, an open circuit voltage of 1.4V, more than 96% of gold removal efficiency in 20h, and equivalent energy production of 2.0kWhkg -1 of gold can be readily achieved in this system. When gold and copper ions coexist, it was confirmed that metallic Cu is formed on the cathodic electrode later than metallic Au formation by XPS analysis. Thus, this system can achieve step by step electrodeposition of gold and copper while the two metal ions coexisting. This work develops a new approach to retrieve valuable metals from aqueous solution or e-wastes. Copyright © 2017 Elsevier B.V. All rights reserved.

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) of U and Pu as well as on actual U-contaminated waste water. In particular, the leaching level of mercury in the Toxicity Characteristic Leaching Procedure (TCLP) test was reduced from 5000 to 0.00085 ppm, and the leaching level of cerium in the long term leaching test (ANS 16.1 test) was below the detection limit. These results show that the chemically bonded phosphate ceramics process may be a simple, inexpensive, and efficient method for stabilizing low-level mixed waste streams.

Projected Salt Waste Production from a Commercial Pyroprocessing Facility

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

Simpson, Michael F.

Pyroprocessing of used nuclear fuel inevitably produces salt waste from electrorefining and/or oxide reduction unit operations. Various process design characteristics can affect the actual mass of such waste produced. This paper examines both oxide and metal fuel treatment, estimates the amount of salt waste generated, and assesses potential benefit of process options to mitigate the generation of salt waste. For reference purposes, a facility is considered in which 100 MT/year of fuel is processed. Salt waste estimates range from 8 to 20 MT/year from considering numerous scenarios. It appears that some benefit may be derived from advanced processes for separatingmore » fission products from molten salt waste, but the degree of improvement is limited. Waste form production is also considered but appears to be economically unfavorable. Direct disposal of salt into a salt basin type repository is found to be the most promising with respect to minimizing the impact of waste generation on the economic feasibility and sustainability of pyroprocessing.« less

The study of heavy metals leaching from waste foundry sands using a one-step extraction

NASA Astrophysics Data System (ADS)

Bożym, Marta

2017-10-01

There are a number of leaching test which are used to evaluate the effect of foundry waste disposal on the environment (TCLP, SPLP, ASTM at al.). Because the spent foundry sand are usually deposited at the ground level and they have a similar structure to the soil, survey mobility of metals using the same methods seems appropriate. One-step extraction allows for the evaluation of the mobility and bioavailability of metals in soil and waste. Waste foundry sands have been successfully used as a component in manufactured soils in U.S., but concern over metal contamination must be eliminated before considering this direction of use. The study evaluated the leaching of heavy metals (Cd, Pb, Cu, Zn, Cr, Ni) from deposited waste foundry sands. The overall, as well as heavy metals were extracted by different type of extractants: H2O, CH3COOH, HCl, EDTA, MgCl2 and NaCOOH. These extractants are most commonly used to study the mobility and bioavailability of metals in soil and waste. In the present study applicable standards and methodology described in the literature in analysis were used. The results allowed to evaluate the bioavailability of metals leached from those wastes.

Prolonged toxicity characteristic leaching procedure for nickel and copper aluminates.

PubMed

Shih, Kaimin; Tang, Yuanyuan

2011-04-01

The toxicity characteristic leaching procedure (TCLP) is a regulatory testing method widely employed to evaluate the environmental friendliness of waste materials. TCLP analysis provides a fast, easy and economical way to determine the mobility of waste pollutants under simulated landfill conditions. Recent studies on metal stabilization have reported the potential for nickel and copper aluminates to form in thermal treatment conditions, and suggested a more reliable method of stabilizing hazardous metals, particularly when products are to be reused. There is thus an urgent need for a convenient and effective method of quantifying metal leachability and identifying the metal leaching behavior of sparingly soluble materials. In this study, standard TCLP analysis was modified into a prolonged leaching experiment to investigate the leaching behavior of nickel and copper oxides (NiO and CuO) and their aluminates (NiAl(2)O(4), CuAl(2)O(4) and CuAlO(2)). The results demonstrate the difficulty of differentiating the leachability of highly insoluble phases, such as NiO and NiAl(2)O(4), using the standard TCLP. The prolonged TCLP method, however, confirmed NiAl(2)O(4) to have a lower degree of intrinsic leachability than NiO and that it could be expected to undergo congruent dissolution under landfill conditions. For the more soluble copper system, the aluminates were still found to possess a much lower degree of leachability, and their leaching behavior to follow an incongruent dissolution pattern. The results of this study prove prolonged TCLP analysis to be a convenient and effective way to evaluate the environmental friendliness of metal waste and to identify the leaching behavior of waste materials.

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...

Method for recovering metals from waste

DOEpatents

Wicks, George G.; Clark, David E.; Schulz, Rebecca L.

2000-01-01

A method for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300-800.degree. C. to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000-1,550.degree. C. at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

Method for recovering metals from waste

DOEpatents

Wicks, George G.; Clark, David E.; Schulz, Rebecca L.

1998-01-01

A method for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300.degree.-800.degree. C. to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000.degree.-1,550.degree. C. at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

Method for recovering metals from waste

DOEpatents

Wicks, G.G.; Clark, D.E.; Schulz, R.L.

1998-12-01

A method is described for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300--800 C to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000--1,550 C at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification. 2 figs.

Bio-processing of solid wastes and secondary resources for metal extraction - A review.

PubMed

Lee, Jae-Chun; Pandey, Banshi Dhar

2012-01-01

Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed in eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted. Copyright © 2011 Elsevier Ltd. All rights reserved.

Method for storage of solid waste

DOEpatents

Mecham, William J.

1976-01-01

Metal canisters for long-term storage of calcined highlevel radioactive wastes can be made self-sealing against a breach in the canister wall by the addition of powdered cement to the canister with the calcine before it is sealed for storage. Any breach in the canister wall will permit entry of water which will mix with the cement and harden to form a concrete patch, thus sealing the opening in the wall of the canister and preventing the release of radioactive material to the cooling water or atmosphere.

Dry halide method for separating the components of spent nuclear fuels

DOEpatents

Christian, Jerry Dale; Thomas, Thomas Russell; Kessinger, Glen F.

1998-01-01

The invention is a nonaqueous, single method for processing multiple spent nuclear fuel types by separating the fission- and transuranic products from the nonradioactive and fissile uranium product. The invention has four major operations: exposing the spent fuels to chlorine gas at temperatures preferably greater than 1200.degree. C. to form volatile metal chlorides; removal of the fission product chlorides, transuranic product chlorides, and any nickel chloride and chromium chloride in a molten salt scrubber at approximately 400.degree. C.; fractional condensation of the remaining volatile chlorides at temperatures ranging from 164.degree. C. to 2.degree. C.; and regeneration and recovery of the transferred spent molten salt by vacuum distillation. The residual fission products, transuranic products, and nickel- and chromium chlorides are converted to fluorides or oxides for vitrification. The method offers the significant advantages of a single, compact process that is applicable to most of the diverse nuclear fuels, minimizes secondary wastes, segregates fissile uranium from the high level wastes to resolve potential criticality concerns, segregates nonradioactive wastes from the high level wastes for volume reduction, and produces a common waste form glass or glass-ceramic.

Dry halide method for separating the components of spent nuclear fuels

DOEpatents

Christian, J.D.; Thomas, T.R.; Kessinger, G.F.

1998-06-30

The invention is a nonaqueous, single method for processing multiple spent nuclear fuel types by separating the fission and transuranic products from the nonradioactive and fissile uranium product. The invention has four major operations: exposing the spent fuels to chlorine gas at temperatures preferably greater than 1200 C to form volatile metal chlorides; removal of the fission product chlorides, transuranic product chlorides, and any nickel chloride and chromium chloride in a molten salt scrubber at approximately 400 C; fractional condensation of the remaining volatile chlorides at temperatures ranging from 164 to 2 C; and regeneration and recovery of the transferred spent molten salt by vacuum distillation. The residual fission products, transuranic products, and nickel- and chromium chlorides are converted to fluorides or oxides for vitrification. The method offers the significant advantages of a single, compact process that is applicable to most of the diverse nuclear fuels, minimizes secondary wastes, segregates fissile uranium from the high level wastes to resolve potential criticality concerns, segregates nonradioactive wastes from the high level wastes for volume reduction, and produces a common waste form glass or glass-ceramic. 3 figs.

Immobilization of metal wastes by reaction with H2S in anoxic basins: concept and elaboration.

PubMed

Schuiling, R D

2013-10-01

Metal wastes are produced in large quantities by a number of industries. Their disposal in isolated waste deposits is certain to cause many subsequent problems, because every material will sooner or later return to the geochemical cycle. The sealing of disposal sites usually starts to leak, often within a short time after the disposal site has been filled. The contained heavy metals are leached from the waste deposit and will contaminate the soil and the groundwater. It is evident that storage as metal sulfides in a permanently anoxic environment is the only safe way to handle metal wastes. The world's largest anoxic basin, the Black Sea, can serve as a georeactor. The metal wastes are sustainably transformed into harmless and immobile solids. These are incorporated in the lifeless bottom muds, where they are stored for millions of years.

Environmental effects of heavy metals derived from the e-waste recycling activities in China: a systematic review.

PubMed

Song, Qingbin; Li, Jinhui

2014-12-01

As the world's leading manufacturing country, China has become the largest dumping ground for e-waste, resulting in serious pollution of heavy metals in China. This study reviews recent studies on environmental effects of heavy metals from the e-waste recycling sites in China, especially Taizhou, Guiyu, and Longtang. The intensive uncontrolled processing of e-waste in China has resulted in the release of large amounts of heavy metals in the local environment, and caused high concentrations of metals to be present in the surrounding air, dust, soils, sediments and plants. Though the pollution of many heavy metals was investigated in the relevant researches, the four kinds of heavy metals (Cu, Pb, Cd and Cr) from e-waste recycling processes attracted more attention. The exceedance of various national and international standards imposed negative effects to the environment, which made the local residents face with the serious heavy metal exposure. In order to protect the environment and human health, there is an urgent need to control and monitor the informal e-waste recycling operations. Copyright © 2014 Elsevier Ltd. All rights reserved.

CEM V based special cementitious materials investigated by means of SANS method. Preliminary results

NASA Astrophysics Data System (ADS)

Dragolici, A. C.; Balasoiu, M.; Orelovich, O. L.; Ionascu, L.; Nicu, M.; Soloviov, D. V.; Kuklin, A. I.; Lizunov, E. I.; Dragolici, F.

2017-05-01

The management of the radioactive waste assume the conditioning in a cement matrix as an embedding, stable, disposal material. Cement matrix is the first and most important engineering barrier against the migration in the environment of the radionuclides contained in the waste packages. Knowing how the microstructure develops is therefore desirable in order to assess the compatibility of radioactive streams with cement and predict waste form performance during storage and disposal. For conditioning wastes containing radioactive aluminum new formulas of low basicity cements, using coatings as a barrier between the metal and the conditioning environment or introducing a corrosion inhibitor in the matrix system are required. Preliminary microstructure investigation of such improved CEM V based cement matrix is reported.

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

Osmanlioglu, Ahmet Erdal

Available in abstract form only. Full text of publication follows: Naturally occurring radioactive material (NORM) in concentrated forms arises both in industry and in nature where natural radioisotopes accumulate at particular sites. Technically enhanced naturally occurring radioactive materials (TE-NORM) often occurs in an acidic environment where precipitates containing radionuclides plate out onto pipe walls, filters, tank linings, etc. Because of the radionuclides are selectively deposited at these sites, radioactivity concentration is extremely higher than the natural concentration. This paper presents characterization and related considerations of TE-NORM wastes in Turkey. Generally, accumulation conditions tend to favour the build-up of radium. Asmore » radium is highly radio-toxic, handling, treatment, storage and disposal of such material requires careful management. Turkey has the only low level waste processing and storage facility (WPSF) in Istanbul. This facility has interim storage buildings and storage area for storage of packaged radioactive waste which are containing artificial radioisotopes, but there is an increasing demand for the storage to accept bulk concentrated TE-NORM wastes from iron-steel and related industries. Most of these wastes generated from scrap metal piles which are imported from other countries. These wastes generally contain radium. (authors)« less

Bio-processing of solid wastes and secondary resources for metal extraction - A review

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

Lee, Jae-chun; Pandey, Banshi Dhar, E-mail: bd_pandey@yahoo.co.uk; CSIR - National Metallurgical Laboratory, Jamshedpur 831007

2012-01-15

Highlights: Black-Right-Pointing-Pointer Review focuses on bio-extraction of metals from solid wastes of industries and consumer goods. Black-Right-Pointing-Pointer Bio-processing of certain effluents/wastewaters with metals is also included in brief. Black-Right-Pointing-Pointer Quantity/composition of wastes are assessed, and microbes used and leaching conditions included. Black-Right-Pointing-Pointer Bio-recovery using bacteria, fungi and archaea is highlighted for resource recycling. Black-Right-Pointing-Pointer Process methodology/mechanism, R and D direction and scope of large scale use are briefly included. - Abstract: Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed inmore » eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted.« less

Use of Carboxymethyl-beta-cyclodextrin (CMCD) as Flushing Agent for Remediation of Metal Contaminated Soil

NASA Astrophysics Data System (ADS)

Skold, M. E.; Thyne, G. D.; McCray, J. E.; Drexler, J. W.

2005-12-01

One of the major challenges in remediating soil and ground water is the presence of mixed organic and inorganic contaminants. Due to their very different behavior, research has to a large extent focused on remediation of either organic or inorganic contaminants rather than mixed waste. Cyclodextrins (CDs) are a group of non-toxic sugar based molecules that do not sorb to soil particles and do not experience pore size exclusion. Thus, they have good hydraulic properties. CDs enhance the solubility of organic compounds by forming inclusion complexes between organic contaminants and the non-polar cavity at the center of the CD. By substituting functional groups to the cyclodextrin molecule it can form complexes with heavy metals. Previous studies have shown that carboxymethyl-beta-cyclodextrin (CMCD) can simultaneously complex organic and inorganic contaminants. The aim of this study is to compare how strongly CMCD complexes several common heavy metals, radioactive elements and a common divalent cation. Results from batch experiments show that CMCD has the ability to complex a wide array of heavy metals and radioactive elements. The solubility of metal oxalates and metal oxides clearly increased in the presence of CMCD. Logarithmic conditional formation constants ranged from 3.5 to 6 for heavy metals and from 3 to 6 for radioactive elements. Calcium, which may compete for binding sites, has a logarithmic conditional formation constant of 3.1. Batch experiments performed at 10 and 25 degrees C showed little temperature effect on conditional formation constants. Results from batch experiments were compared to results from column experiments where Pb was sorbed onto hydrous ferric oxide coated sand and subsequently removed by a CMCD solution. The results indicate that CMCD is a potential flushing agent for remediation of mixed waste sites.

Turning Waste Chemicals into Wealth—A New Approach To Synthesize Efficient Cathode Material for an Li–O 2 Battery

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

Yao, Ying; Wu, Feng

An Li–O 2 battery requires the oxygen-breathing cathode to be highly electronically conductive, rapidly oxygen diffusive, structurally stable, and often times electrocatalytically active. Catalyst-decorated porous carbonaceous materials are the chosen air cathode in this regard. Alternatively, biomass-derived carbonaceous materials possess great ability to remove heavy and toxic metal ions from waste, forming a metal-adsorbed porous carbonaceous material. The similar structure between the air cathode and the metal-adsorbed biomass-derived carbon nicely bridges these two irrelevant areas. In this study, we investigated the electrochemical activity of a biochar material Ag-ESB directly synthesized from ethanol sludge residue in a rechargeable aprotic Li–O 2more » battery. Ag ions were adsorbed from sewage and became Ag nanoparticles with uniform coverage on the biochar surface. The as-prepared material exhibits good electrochemical behavior in battery testing, especially toward the battery efficiency and cyclability. This study provides the possibility of synthetically efficient cathode material by reusing “waste” such as biofuel sludge residue. It is an economically and environmentally friendly approach both for an energy-storage system and for waste recycling.« less

Fuel conditioning facility electrorefiner start-up results

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

Goff, K.M.; Mariani, R.D.; Vaden, D.

1996-05-01

At ANL-West, there are several thousand kilograms of metallic spent nuclear fuel containing bond sodium. This fuel will be treated in the Fuel Conditioning Facility (FCF) at ANL-West to produce stable waste forms for storage and disposal. The treatment operations will make use of an electrometallurgical process employing molten salts and liquid metals. The treatment equipment is presently undergoing testing with depleted uranium. Operations with irradiated fuel will commence when the environmental evaluation for FCF is complete.

Disposal of spent fuel

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

Blomeke, J O; Ferguson, D E; Croff, A G

1978-01-01

Based on preliminary analyses, spent fuel assemblies are an acceptable form for waste disposal. The following studies appear necessary to bring our knowledge of spent fuel as a final disposal form to a level comparable with that of the solidified wastes from reprocessing: 1. A complete systems analysis is needed of spent fuel disposition from reactor discharge to final isolation in a repository. 2. Since it appears desirable to encase the spent fuel assembly in a metal canister, candidate materials for this container need to be studied. 3. It is highly likely that some ''filler'' material will be needed betweenmore » the fuel elements and the can. 4. Leachability, stability, and waste-rock interaction studies should be carried out on the fuels. The major disadvantages of spent fuel as a disposal form are the lower maximum heat loading, 60 kW/acre versus 150 kW/acre for high-level waste from a reprocessing plant; the greater long-term potential hazard due to the larger quantities of plutonium and uranium introduced into a repository; and the possibility of criticality in case the repository is breached. The major advantages are the lower cost and increased near-term safety resulting from eliminating reprocessing and the treatment and handling of the wastes therefrom.« less

An overview of metals recovery from thermal power plant solid wastes.

PubMed

Meawad, Amr S; Bojinova, Darinka Y; Pelovski, Yoncho G

2010-12-01

Thermal power plants (TPPs) that burn fossil fuels emit several pollutants linked to the environmental problems of acid rain, urban ozone, and the possibility of global climate change. As coal is burned in a power plant, its noncombustible mineral content is partitioned into bottom ash, which remains in the furnace, and fly ash, which rises with flue gases. Two other by-products of coal combustion air-pollution control technologies are flue gas desulfurization (FGD) wastes and fluidized-bed combustion (FBC) wastes. This paper analyzed and summarized the generation, characteristics and application of TPP solid wastes and discussed the potential effects of such solid wastes on the environment. On this basis, a review of a number of methods for recovery of metals from TPP solid wastes was made. They usually contain a quantity of valuable metals and they are actually a secondary resource of metals. By applying mineral processing technologies and hydrometallurgical and biohydrometallurgical processes, it is possible to recover metals such as Al, Ga, Ge, Ca, Cd, Fe, Hg, Mg, Na, Ni, Pb, Ra, Th, V, Zn, etc., from TPP solid wastes. Recovery of metals from such wastes and its utilization are important not only for saving metal resources, but also for protecting the environment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Nuclear waste storage container with metal matrix

DOEpatents

Sump, Kenneth R.

1978-01-01

The invention relates to a storage container for high-level waste having a metal matrix for the high-level waste, thereby providing greater impact strength for the waste container and increasing heat transfer properties.

Method for processing aqueous wastes

DOEpatents

Pickett, John B.; Martin, Hollis L.; Langton, Christine A.; Harley, Willie W.

1993-01-01

A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

[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.

Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

PubMed

Drobíková, Klára; Plachá, Daniela; Motyka, Oldřich; Gabor, Roman; Kutláková, Kateřina Mamulová; Vallová, Silvie; Seidlerová, Jana

2016-02-01

Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combining Nitrilotriacetic Acid and Permeable Barriers for Enhanced Phytoextraction of Heavy Metals from Municipal Solid Waste Compost by and Reduced Metal Leaching.

PubMed

Zhao, Shulan; Jia, Lina; Duo, Lian

2016-05-01

Phytoextraction has the potential to remove heavy metals from contaminated soil, and chelants can be used to improve the capabilities of phytoextraction. However, environmentally persistent chelants can cause metal leaching and groundwater pollution. A column experiment was conducted to evaluate the viability of biodegradable nitrilotriacetic acid (NTA) to increase the uptake of heavy metals (Cd, Cr, Ni, Pb, Cu, and Zn) by L. in municipal solid waste (MSW) compost and to evaluate the effect of two permeable barrier materials, bone meal and crab shell, on metal leaching. The application of NTA significantly increased the concentrations and uptake of heavy metals in . The enhancement was more pronounced at higher dosages of NTA. In the 15 mmol kg NTA treatment using a crab shell barrier, the Cr and Ni concentrations in the plant shoots increased by approximately 8- and 10-fold, respectively, relative to the control. However, the addition of NTA also caused significant heavy metal leaching from the MSW compost. Bone meal and crab shell barriers positioned between the compost and the subsoil were effective in preventing metal leaching down through the soil profile by the retention of metals in the barrier. The application of a biodegradable chelant and the use of permeable barriers is a viable form of enhanced phytoextraction to increase the removal of metals and to reduce possible leaching. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

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

Asmussen, R. Matthew; Pearce, Carolyn I.; Miller, Brian W.

A cementitious waste form, Cast Stone, is a possible candidate technology for the immobilization of low activity nuclear waste (LAW) at the Hanford site. This paper focuses on the addition of getter materials to Cast Stone that can sequester Tc from the LAW, and in turn, lower Tc release from the Cast Stone. Two getters which produce different products upon sequestering Tc from LAW were tested: Sn(II) apatite (Sn-A) that removes Tc as a Tc(IV)-oxide and potassium metal sulfide (KMS-2) that removes Tc as a Tc(IV)-sulfide species, allowing for a comparison of stability of the form of Tc upon enteringmore » the waste form. The Cast Stone with KMS-2 getter had the best performance with addition equivalent to ~0.08 wt% of the total waste form mass. The observed diffusion (D obs) of Tc decreased from 4.6 ± 0.2 × 10 -12 cm 2/s for Cast Stone that did not contain a getter to 5.4 ± 0.4 × 10 -13 cm 2/s for KMS-2 containing Cast Stone. Finally, it was found that Tc-sulfide species are more stable against re-oxidation within getter containing Cast Stone compared with Tc-oxide and is the origin of the decrease in Tc D obs when using the KMS-2.« less

Characterization of ash melting behaviour at high temperatures under conditions simulating combustible solid waste gasification.

PubMed

Niu, Miaomiao; Dong, Qing; Huang, Yaji; Jin, Baosheng; Wang, Hongyan; Gu, Haiming

2018-05-01

To achieve high-temperature gasification-melting of combustible solid waste, ash melting behaviour under conditions simulating high-temperature gasification were studied. Raw ash (RA) and gasified ash (GA) were prepared respectively by waste ashing and fluidized bed gasification. Results of microstructure and composition of the two-ash indicated that GA showed a more porous structure and higher content of alkali and alkali earth metals among metallic elements. Higher temperature promoted GA melting and could reach a complete flowing state at about 1250°C. The order of melting rate of GA under different atmospheres was reducing condition > inert condition > oxidizing condition, which might be related to different existing forms of iron during melting and different flux content with atmosphere. Compared to RA, GA showed lower melting activity at the same condition due to the existence of an unconverted carbon and hollow structure. The melting temperature for sufficient melting and separation of GA should be at least 1250°C in this work.

Transformation of heavy metal fractionation under changing environments: a case study of a drainage system in an e-waste dismantling community.

PubMed

Damrongsiri, Seelawut

2018-04-01

The change in environmental conditions during the transportation of contaminated soil and sediment was expected to affect the transformation of heavy metal fractionation. This study disclosed the serious contamination of copper (Cu), lead (Pb), and zinc (Zn) in the sewer sediment of an e-waste dismantling community in Thailand which may be caused by flushed contaminated soil and e-waste fragments. Two environmental conditions were simulated to observe the transformation of heavy metal fractionation. The anoxic sewer condition was induced using high substrate and sulfate in a closed container. The aeration of anoxic contaminated sediment was applied to simulate the transformation to an oxidative environment. The BCR sequential extraction was applied for heavy metal fractionation in this study. The study results exhibited that when heavy metal contaminated soil was transferred into this induced anoxic condition, fractionation was redistributed based on the chemical change of system that tends to be associated into F3 (oxidizable fraction) > F2 (reducible fraction) > F1 (acid soluble/exchangeable fraction). Cu exhibited the outstanding capability association to F3. The iron sulfide was not observed as usual due to its lower capability than Cu, Pb, and Zn. When contaminated sediment was transported to a more oxidative environment, the heavy metals fractionation would be redistributed again among those new environment media. It is noteworthy that F3 of Cu was stable even in oxic conditions. F2 of Fe was not developed by this oxic condition, possibly because its dehydration process was limited. The redistribution under an oxic environment became F1 > F2 > F3 indicating their more available form. This transformation was imperative and should be taken into account in heavy metal contaminated site management and control.

Heavy metals in hair of residents in an e-waste recycling area, south China: contents and assessment of bodily state.

PubMed

Zheng, Jing; Luo, Xiao-Jun; Yuan, Jian-Gang; He, Luo-Yiyi; Zhou, Yi-Hui; Luo, Yong; Chen, She-Jun; Mai, Bi-Xian; Yang, Zhong-Yi

2011-11-01

Heavy metals were measured in hair from occupationally and nonoccupationally exposed populations in an e-waste recycling area and from residents from a control rural town. The levels of five heavy metals were in the following order of Zn > Pb, Cu > Cd > Ni, with the highest levels found in the occupationally exposed workers. The levels of Cd, Pb, and Cu were significantly higher in residents from the e-waste recycling area than in the control area. Elevated Cd, Pb, and Cu contents along with significant positive correlations between them in hair from the e-waste recycling area indicated that these metals were likely to have originated from the e-waste recycling activities. The similarity in heavy metal pattern between children and occupationally exposed workers indicated that children are particularly vulnerable to heavy metal pollution caused by e-waste recycling activities. The increased Cu exposure might be a benefit for the insufficient intake of Cu in the studied area. However, the elevated hair Cd and Pb levels implied that the residents in the e-waste area might be at high risk of toxic metal, especially for children and occupationally exposed workers.

Fate of metals contained in waste electrical and electronic equipment in a municipal waste treatment process

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

Oguchi, Masahiro, E-mail: oguchi.masahiro@nies.go.jp; Sakanakura, Hirofumi, E-mail: sakanakura@nies.go.jp; Terazono, Atsushi, E-mail: terazono@nies.go.jp

2012-01-15

Highlights: Black-Right-Pointing-Pointer The fate of 55 metals during shredding and separation of WEEE was investigated. Black-Right-Pointing-Pointer Most metals were mainly distributed to the small-grain fraction. Black-Right-Pointing-Pointer Much of metals in WEEE being treated as municipal waste in Japan end up in landfills. Black-Right-Pointing-Pointer Pre-sorting of small digital products reduces metals to be landfilled at some level. Black-Right-Pointing-Pointer Consideration of metal recovery from other middle-sized WEEE is still important. - Abstract: In Japan, waste electrical and electronic equipment (WEEE) that is not covered by the recycling laws are treated as municipal solid waste. A part of common metals are recovered duringmore » the treatment; however, other metals are rarely recovered and their destinations are not clear. This study investigated the distribution ratios and substance flows of 55 metals contained in WEEE during municipal waste treatment using shredding and separation techniques at a Japanese municipal waste treatment plant. The results revealed that more than half of Cu and most of Al contained in WEEE end up in landfills or dissipate under the current municipal waste treatment system. Among the other metals contained in WEEE, at least 70% of the mass was distributed to the small-grain fraction through the shredding and separation and is to be landfilled. Most kinds of metals were concentrated several fold in the small-grain fraction through the process and therefore the small-grain fraction may be a next target for recovery of metals in terms of both metal content and amount. Separate collection and pre-sorting of small digital products can work as effective way for reducing precious metals and less common metals to be landfilled to some extent; however, much of the total masses of those metals would still end up in landfills and it is also important to consider how to recover and utilize metals contained in other WEEE such as audio/video equipment.« less

U.S. program assessing nuclear waste disposal in space - A status report

NASA Technical Reports Server (NTRS)

Rice, E. E.; Priest, C. C.; Friedlander, A. L.

1980-01-01

Various concepts for the space disposal of nuclear waste are discussed, with attention given to the destinations now being considered (high earth orbit, lunar orbit, lunar surface, solar orbit, solar system escape, sun). Waste mixes are considered in the context of the 'Purex' (Plutonium and Uranium extraction) process and the potential forms for nuclear waste disposal (ORNL cermet, Boro-silicate glass, Metal matrix, Hot-pressed supercalcine) are described. Preliminary estimates of the energy required and the cost surcharge needed to support the space disposal of nuclear waste are presented (8 metric tons/year, requiring three Shuttle launches). When Purex is employed, the generated electrical energy needed to support the Shuttle launches is shown to be less than 1%, and the projected surcharge to electrical users is shown to be slightly more than two mills/kW-hour.

Remaining Sites Verification Package for the 116-C-3, 105-C Chemical Waste Tanks, Waste Site Reclassification Form 2008-002

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

L. M. Dittmer

2008-01-31

The 116-C-3 waste site consisted of two underground storage tanks designed to receive mixed waste from the 105-C Reactor Metals Examination Facility chemical dejacketing process. Confirmatory evaluation and subsequent characterization of the site determined that the southern tank contained approximately 34,000 L (9,000 gal) of dejacketing wastes, and that the northern tank was unused. In accordance with this evaluation, the verification sampling and modeling results support a reclassification of this site to Interim Closed Out. The results of verification sampling demonstrate that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils.more » The results also show that residual contaminant concentrations are protective of groundwater and the Columbia River.« less

40 CFR Appendix Xi to Part 268 - Metal Bearing Wastes Prohibited From Dilution in a Combustion Unit According to 40 CFR 268.3(c)

Code of Federal Regulations, 2013 CFR

2013-07-01

... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. XI Appendix XI to Part 268—Metal Bearing Wastes Prohibited From Dilution in a Combustion... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Metal Bearing Wastes Prohibited From...

40 CFR Appendix Xi to Part 268 - Metal Bearing Wastes Prohibited From Dilution in a Combustion Unit According to 40 CFR 268.3(c)

Code of Federal Regulations, 2014 CFR

2014-07-01

... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. XI Appendix XI to Part 268—Metal Bearing Wastes Prohibited From Dilution in a Combustion... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Metal Bearing Wastes Prohibited From...

Process for treating waste water having low concentrations of metallic contaminants

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

Looney, Brian B; Millings, Margaret R; Nichols, Ralph L

A process for treating waste water having a low level of metallic contaminants by reducing the toxicity level of metallic contaminants to an acceptable level and subsequently discharging the treated waste water into the environment without removing the treated contaminants.

The Use of Induction Melting for the Treatment of Metal Radioactive Waste - 13088

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

Zherebtsov, Alexander; Pastushkov, Vladimir; Poluektov, Pavel

2013-07-01

The aim of the work is to assess the efficacy of induction melting metal for recycling radioactive waste in order to reduce the volume of solid radioactive waste to be disposed of, and utilization of the metal. (authors)

Biomineralization of copper: Solutions for waste remediation and biomining

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

Ashby, C.R.; Thompson, S.A.; Crusberg, T.C.

1997-12-31

The fungus Penicillium ochro-chloron is able to extract copper from aqueous solutions and form insoluble copper precipitates within the matrix of fungal mycelia. The formation of these complexes is probably a detoxification mechanism used by the organism to deal with the potentially lethal concentrations of heavy metals. Metal immobilization occurs external to the cells but within the mycelia when the solubility products of copper phosphate and copper oxalate are exceeded. This process may be exploited in biomining to remove and recover copper and perhaps other heavy metals that have become solubilized in pit mine lakes.

Mechanochemical processing of molybdenum and vanadium sulfides for metal recovery from spent catalysts wastes.

PubMed

Li, Zhao; Chen, Min; Zhang, Qiwu; Liu, Xinzhong; Saito, Fumio

2017-02-01

This work describes the mechanochemical transformations of molybdenum and vanadium sulfides into corresponding molybdate and vanadate, to serve as a new environment-friendly approach for processing hazardous spent hydrodesulphurization (HDS) catalysts solid waste to achieve an easy recovery of not only molybdenum and vanadium but also nickel and cobalt. Co-grinding the molybdenum and vanadium sulfides with oxidants and sodium carbonate stimulates solid-state reactions without any heating aid to form metal molybdates and vanadates. The reactions proceed with an increase in grinding time and were enhanced by using more sodium carbonate and stronger oxidant. The necessary conditions for the successful transformation can be explained on the basis of thermodynamic analyses, namely a negative change in Gibbs free energy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterizing the environmental impact of metals in construction and demolition waste.

PubMed

Yu, Danfeng; Duan, Huabo; Song, Qingbin; Li, Xiaoyue; Zhang, Hao; Zhang, Hui; Liu, Yicheng; Shen, Weijun; Wang, Jinben

2018-05-01

Large quantities of construction and demolition (C&D) waste are generated in China every year, but their potential environmental impacts on the surrounding areas are rarely assessed. This study focuses on metals contained in C&D waste, characterizing the metal concentrations and their related environmental risks. C&D waste samples were collected in Shenzhen City, China, from building demolition sites, renovation areas undergoing refurbishment, landfill sites, and recycling companies (all located in Shenzhen city) that produce recycled aggregate, in order to identify pollution levels of the metals As, Cd, Cr, Cu, Pb, Ni, and Zn. The results showed that (1) the metal concentrations in most demolition and renovation waste samples were below the soil environmental quality standard for agricultural purposes (SQ-Agr.) in China; (2) Cd, Cu, and Zn led to relatively higher environmental risks than other metals, especially for Zn (DM5 tile sample, 360 mg/kg; R4 tile sample, 281 mg/kg); (3) non-inert C&D waste such as wall insulation and foamed plastic had high concentrations of As and Cd, so that these materials required special attention for sound waste management; and (4) C&D waste collected from landfill sites had higher concentrations of Cd and Cu than did waste collected from demolition and refurbishment sites.

An overview of the Gold King Mine Release and its Transport ...

EPA Pesticide Factsheets

On August 5, 2015, a large acidic mine pool trapped behind a collapsed mine structure and rock debris in the Gold King Mine (GKM) was accidently breached releasing approximately 11.3 million liters (3 million gallons) of low pH (~3) metal contaminated mine drainage into a small tributary in the headwaters of the Animas River in southwestern Colorado. The release introduced approximately 490,000 kg of dissolved and particulate metals over a 12-hour period into the Animas River at Silverton, CO, located 13 km downstream from the mine. The mine effluent contained 2,900 kg of dissolved metals. Most of the released metals were eroded from the old waste pile outside the mine entrance and within Cement Creek by the rushing water. The release introduced large quantities of particulate aluminum, iron, manganese, lead, copper, arsenic and zinc to the Animas River, of which 15,000 kg was in dissolved form To be presented at the New Mexico Water Institute Symposium, 2nd Annual Conference on Environmental Conditionsof the Animas and San Juan Watersheds with Emphasis on Gold King Mine and Other Mine Waste Issues.

Calcium phosphate stabilization of fly ash with chloride extraction.

PubMed

Nzihou, Ange; Sharrock, Patrick

2002-01-01

Municipal solid waste incinerator by products include fly ash and air pollution control residues. In order to transform these incinerator wastes into reusable mineral species, soluble alkali chlorides must be separated and toxic trace elements must be stabilized in insoluble form. We show that alkali chlorides can be extracted efficiently in an aqueous extraction step combining a calcium phosphate gel precipitation. In such a process, sodium and potassium chlorides are obtained free from calcium salts, and the trace metal ions are immobilized in the calcium phosphate matrix. Moderate calcination of the chemically treated fly ash leads to the formation of cristalline hydroxylapatite. Fly ash spiked with copper ions and treated by this process shows improved stability of metal ions. Leaching tests with water or EDTA reveal a significant drop in metal ion dissolution. Hydroxylapatite may trap toxic metals and also prevent their evaporation during thermal treatments. Incinerator fly ash together with air pollution control residues, treated by the combined chloride extraction and hydroxylapatite formation process may be considered safe to use as a mineral filler in value added products such as road base or cement blocks.

E.I. DuPont De Nemours & Company/Oberlin Filter Company Microfiltration Technology. Applications Analysis Report

EPA Science Inventory

This report evaluates the DuPont/Oberlin microfiltration technology’s ability to remove metals (present in soluble or insoluble form) and particulates from liquid wastes while producing a dry filter cake and a filtrate that meet applicable disposal requirements. This report also ...

Cold crucible induction melter test for crystalline ceramic waste form fabrication: A feasibility assessment

DOE PAGES

Amoroso, Jake W.; Marra, James; Dandeneau, Christopher S.; ...

2017-01-18

The first scaled proof-of-principle cold crucible induction melter (CCIM) test to process a multiphase ceramic waste form from a simulated combined (Cs/Sr, lanthanide and transition metal fission products) commercial used nuclear fuel waste stream was recently conducted in the United States. X-ray diffraction, 2-D X-ray absorption near edge structure (XANES), electron microscopy, inductively coupled plasma-atomic emission spectroscopy (and inductively coupled plasma-mass spectroscopy for Cs), and product consistency tests were used to characterize the fabricated CCIM material. Characterization analyses confirmed that a crystalline ceramic with a desirable phase assemblage was produced from a melt using a CCIM. We identified primary hollandite,more » pyrochlore/zirconolite, and perovskite phases in addition to minor phases rich in Fe, Al, or Cs. The material produced in the CCIM was chemically homogeneous and displayed a uniform phase assemblage with acceptable aqueous chemical durability.« less

Determination of the Pb, Cr, and Cd distribution patterns with various chlorine additives in the bottom ashes of a low-temperature two-stage fluidized bed incinerator by chemical sequential extraction.

PubMed

Peng, Tzu-Huan; Lin, Chiou-Liang; Wey, Ming-Yen

2015-09-15

A novel low-temperature two-stage fluidized bed (LTTSFB) incinerator has been successfully developed to control heavy-metal emissions during municipal solid waste (MSW) treatment. However, the characteristics of the residual metal patterns during this process are still unclear. The aim of this study was to investigate the metal patterns in the different partitions of the LTTSFB bottom ash by chemical sequential extraction. Artificial waste was used to simulate the MSW. Different parameters including the first-stage temperature, chloride additives, and operating gas velocity were also considered. Results indicated that during the low-temperature treatment process, a high metal mobility phase exists in the first-stage sand bed. The main patterns of Cd, Pb, and Cr observed were the water-soluble, exchangeable, and residual forms, respectively. With the different Cl additives, the results showed that polyvinyl chloride addition increased metal mobility in the LTTSFB bottom ash, while, sodium chloride addition may have reduced metal mobility due to the formation of eutectic material. The second-stage sand bed was found to have a lower risk of metal leaching. The results also suggested that, the residual ashes produced by the LTTSFB system must be taken into consideration given their high metal mobility. Copyright © 2015 Elsevier B.V. All rights reserved.

Status of electronic waste recycling techniques: a review.

PubMed

Abdelbasir, Sabah M; Hassan, Saad S M; Kamel, Ayman H; El-Nasr, Rania Seif

2018-05-08

The increasing use of electrical and electronic equipment leads to a huge generation of electronic waste (e-waste). It is the fastest growing waste stream in the world. Almost all electrical and electronic equipment contain printed circuit boards as an essential part. Improper handling of these electronic wastes could bring serious risk to human health and the environment. On the other hand, proper handling of this waste requires a sound management strategy for awareness, collection, recycling, and reuse. Nowadays, the effective recycling of this type of waste has been considered as a main challenge for any society. Printed circuit boards (PCBs), which are the base of many electronic industries, are rich in valuable heavy metals and toxic halogenated organic substances. In this review, the composition of different PCBs and their harmful effects are discussed. Various techniques in common use for recycling the most important metals from the metallic fractions of e-waste are illustrated. The recovery of metals from e-waste material after physical separation through pyrometallurgical, hydrometallurgical, or biohydrometallurgical routes is also discussed, along with alternative uses of non-metallic fraction. The data are explained and compared with the current e-waste management efforts done in Egypt. Future perspectives and challenges facing Egypt for proper e-waste recycling are also discussed.

Method for recovering materials from waste

DOEpatents

Wicks, G.G.; Clark, D.E.; Schulz, R.L.

1994-01-01

A method for recovering metals from metals-containing wastes, a vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300--800{degrees}C to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1000--1550{degrees}C at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

A new strain for recovering precious metals from waste printed circuit boards.

PubMed

Ruan, Jujun; Zhu, Xingjiong; Qian, Yiming; Hu, Jian

2014-05-01

A new strain, Pseudomonas Chlororaphis (PC), was found for dissolving gold, silver, and copper from the metallic particles of crushed waste printed circuit boards (PCBs). The optimized conditions that greatly improved the ability of producing CN- (for dissolving metals) were obtained. Dissolving experiments of pure gold, silver, and copper showed that the metals could be changed into Au+, Ag+, and Cu2+. PC cells and their secreta would adsorb metallic ions. Meanwhile, metallic ions destroyed the growth of PC. Dissolving experiments of metallic particles from crushed waste PCBs were performed by PC. The results indicated that 8.2% of the gold, 12.1% silver, and 52.3% copper were dissolved into solution. This paper contributed significance information to recovering precious metals from waste PCBs by bioleaching. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Method for forming consumable electrodes from metallic chip scraps

DOEpatents

Girshov, Vladimir Leonidovich; Podpalkin, Arcady Munjyvich; Treschevskiy, Arnold Nikolayevich; Abramov, Alexey Alexandrovich

2005-10-11

The method relates to metallurgical recycling of waste products, preferably titanium alloys chips scrap. Accordingly after crushing and cleaning, the chip scrap is subjected to vacuum-thermal degassing (VTD); the chip scrap is pressed into briquettes; the briquettes are placed into a mould allowing sufficient remaining space for the addition of molten metal alloy; the mould is pre-heated before filling with the molten metal alloy; the mould remaining space is filled with molten metal alloy. After cooling, the electrode is removed from the mould. The method provides a means for 100% use of chip scrap in producing consumable electrodes having increased mechanical strength and reduced interstitial impurities content leading to improved secondary cast alloys.

Method for treating materials for solidification

DOEpatents

Jantzen, Carol M.; Pickett, John B.; Martin, Hollis L.

1995-01-01

A method for treating materials such as wastes for solidification to form a solid, substantially nonleachable product. Addition of reactive silica rather than ordinary silica to the material when bringing the initial molar ratio of its silica constituent to a desired ratio within a preselected range increases the solubility and retention of the materials in the solidified matrix. Materials include hazardous, radioactive, mixed, and heavy metal species. Amounts of other constituents of the material, in addition to its silica content are also added so that the molar ratio of each of these constituents is within the preselected ranges for the final solidified product. The mixture is then solidified by cement solidification or vitrification. The method can be used to treat a variety of wastes, including but not limited to spent filter aids from waste water treatment, waste sludges, combinations of spent filter aids and waste sludges, combinations of supernate and waste sludges, incinerator ash, incinerator offgas blowdown, combinations of incinerator ash and offgas blowdown, cementitious wastes and contaminated soils.

Impact of informal electronic waste recycling on metal concentrations in soils and dusts.

PubMed

Ohajinwa, Chimere May; van Bodegom, Peter M; Vijver, Martina G; Peijnenburg, Willie J G M

2018-07-01

Electronic and electrical equipment contains over 1000 different substances, including metals. During informal e-waste recycling some of these substances such as metals, are released into the environment causing environmental pollution. This study assessed the impact of different informal e-waste recycling activities (burning, dismantling, and repairing) on metal concentrations in top soils and various dust. A comparative cross-sectional study design was adopted to assess metal concentrations in top soils and in various dust samples from multiple e-waste recycling sites. Metal concentrations at e-waste recycling sites were compared to the concentrations at control sites in three study locations in Nigeria (Lagos, Ibadan, and Aba). In the three study locations, mean metal concentrations at the e-waste recycling sites exceeded the concentrations at the control sites and the Nigerian standard guideline values by 100 s to 1000 s times. Burning sites showed the highest pollution level, followed by dismantling sites, then repair sites. Our findings show serious environmental and public health concerns. The metal concentrations were also higher than levels reported in other studies at the same locations in Nigeria, indicating that the situation is worsening. This study provides scientific evidence for an urgent need to develop effective strategies to strengthen enforcement of existing e-waste regulations in Nigeria. Copyright © 2018 Elsevier Inc. All rights reserved.

Impact of metals in surface matrices from formal and informal electronic-waste recycling around Metro Manila, the Philippines, and intra-Asian comparison.

PubMed

Fujimori, Takashi; Takigami, Hidetaka; Agusa, Tetsuro; Eguchi, Akifumi; Bekki, Kanae; Yoshida, Aya; Terazono, Atsushi; Ballesteros, Florencio C

2012-06-30

We report concentrations, enrichment factors, and hazard indicators of 11 metals (Ag, As, Cd, Co, Cu, Fe, In, Mn, Ni, Pb, and Zn) in soil and dust surface matrices from formal and informal electronic waste (e-waste) recycling sites around Metro Manila, the Philippines, referring to soil guidelines and previous data from various e-waste recycling sites in Asia. Surface dust from e-waste recycling sites had higher levels of metal contamination than surface soil. Comparison of formal and informal e-waste recycling sites (hereafter, "formal" and "informal") revealed differences in specific contaminants. Formal dust contained a mixture of serious pollutant metals (Ni, Cu, Pb, and Zn) and Cd (polluted modestly), quite high enrichment metals (Ag and In), and crust-derived metals (As, Co, Fe, and Mn). For informal soil, concentration levels of specific metals (Cd, Co, Cu, Mn, Ni, Pb, and Zn) were similar among Asian recycling sites. Formal dust had significantly higher hazardous risk than the other matrices (p<0.005), excluding informal dust (p=0.059, almost significant difference). Thus, workers exposed to formal dust should protect themselves from hazardous toxic metals (Pb and Cu). There is also a high health risk for children ingesting surface matrices from informal e-waste recycling sites. Copyright © 2012 Elsevier B.V. All rights reserved.

Forming artificial soils from waste materials for mine site rehabilitation

NASA Astrophysics Data System (ADS)

Yellishetty, Mohan; Wong, Vanessa; Taylor, Michael; Li, Johnson

2014-05-01

Surface mining activities often produce large volumes of solid wastes which invariably requires the removal of significant quantities of waste rock (overburden). As mines expand, larger volumes of waste rock need to be moved which also require extensive areas for their safe disposal and containment. The erosion of these dumps may result in landform instability, which in turn may result in exposure of contaminants such as trace metals, elevated sediment delivery in adjacent waterways, and the subsequent degradation of downstream water quality. The management of solid waste materials from industrial operations is also a key component for a sustainable economy. For example, in addition to overburden, coal mines produce large amounts of waste in the form of fly ash while sewage treatment plants require disposal of large amounts of compost. Similarly, paper mills produce large volumes of alkaline rejected wood chip waste which is usually disposed of in landfill. These materials, therefore, presents a challenge in their use, and re-use in the rehabilitation of mine sites and provides a number of opportunities for innovative waste disposal. The combination of solid wastes sourced from mines, which are frequently nutrient poor and acidic, with nutrient-rich composted material produced from sewage treatment and alkaline wood chip waste has the potential to lead to a soil suitable for mine rehabilitation and successful seed germination and plant growth. This paper presents findings from two pilot projects which investigated the potential of artificial soils to support plant growth for mine site rehabilitation. We found that pH increased in all the artificial soil mixtures and were able to support plant establishment. Plant growth was greatest in those soils with the greatest proportion of compost due to the higher nutrient content. These pot trials suggest that the use of different waste streams to form an artificial soil can potentially be used in mine site rehabilitation where there is a nutrient-rich source of waste.

Corrosion of Metal Inclusions In Bulk Vitrification Waste Packages. Erratum

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

Smith, Gary L.

This report refers to or contains K g values for glasses LAWA44, LAWB45 and LAWC22 affected by calculations errors as identified by Papathanassiu et al. (2011). The corrected K g values are reported in an erratum included in the revised version of the original report. The revised report can be referenced as follows: Pierce E. M. et al. (2004) Waste Form Release Data Package for the 2005 Integrated Disposal Facility Performance Assessment. PNNL-14805 Rev. 0 Erratum. Pacific Northwest National Laboratory, Richland, WA, USA.

Method for extracting metals from aqueous waste streams for long term storage

DOEpatents

Chaiko, D.J.

1995-03-07

A liquid-liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average individual particle sizes of approximately 40 nanometers. 2 figs.

Method for extracting metals from aqueous waste streams for long term storage

DOEpatents

Chaiko, D.J.

1993-01-01

A liquid-liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average. individual particle sizes of approximately 40 manometers.

Method for extracting metals from aqueous waste streams for long term storage

DOEpatents

Chaiko, David J.

1995-01-01

A liquid--liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average individual particle sizes of approximately 40 nanometers.

Mass, energy and material balances of SRF production process. Part 2: SRF produced from construction and demolition waste.

PubMed

Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

2014-11-01

In this work, the fraction of construction and demolition waste (C&D waste) complicated and economically not feasible to sort out for recycling purposes is used to produce solid recovered fuel (SRF) through mechanical treatment (MT). The paper presents the mass, energy and material balances of this SRF production process. All the process streams (input and output) produced in MT waste sorting plant to produce SRF from C&D waste are sampled and treated according to CEN standard methods for SRF. Proximate and ultimate analysis of these streams is performed and their composition is determined. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. By mass balance means the overall mass flow of input waste material stream in the various output streams and material balances mean the mass flow of components of input waste material stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. The results from mass balance of SRF production process showed that of the total input C&D waste material to MT waste sorting plant, 44% was recovered in the form of SRF, 5% as ferrous metal, 1% as non-ferrous metal, and 28% was sorted out as fine fraction, 18% as reject material and 4% as heavy fraction. The energy balance of this SRF production process showed that of the total input energy content of C&D waste material to MT waste sorting plant, 74% was recovered in the form of SRF, 16% belonged to the reject material and rest 10% belonged to the streams of fine fraction and heavy fraction. From the material balances of this process, mass fractions of plastic (soft), paper and cardboard, wood and plastic (hard) recovered in the SRF stream were 84%, 82%, 72% and 68% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC) and rubber material was found in the reject material stream. Streams of heavy fraction and fine fraction mainly contained non-combustible material (such as stone/rock, sand particles and gypsum material). Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of spreading olive mill waste water on agricultural soils for leaching of metal micronutrients and cations.

PubMed

Aharonov-Nadborny, R; Tsechansky, L; Raviv, M; Graber, E R

2017-07-01

Olive mill waste water (OMWW) is an acidic (pH 4-5), saline (EC ∼ 5-10 mS cm -1 ), blackish-red aqueous byproduct of the three phase olive oil production process, with a high chemical oxygen demand (COD) of up to 220,000 mg L -1 . OMWW is conventionally disposed of by uncontrolled dumping into the environment or by semi-controlled spreading on agricultural soils. It was hypothesized that spreading such liquids on agricultural soils could result in the release and mobilization of indigenous soil metals. The effect of OMWW spreading on leaching of metal cations (Na, K, Mg, Mn, Fe, Cu, Zn) was tested in four non-contaminated agricultural soils having different textures (sand, clay loam, clay, and loam) and chemical properties. While the OMWW contributed metals to the soil solution, it also mobilized indigenous soil metals as a function of soil clay content, cation exchange capacity (CEC), and soil pH-buffer capacity. Leaching of soil-originated metals from the sandy soil was substantially greater than from the loam and clay soils, while the clay loam was enriched with metals derived from the OMWW. These trends were attributed to cation exchange and organic-metal complex formation. The organic matter fraction of OMWW forms complexes with metal cations; these complexes may be mobile or precipitate, depending on the soil chemical and physical environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methods for recovering precious metals from industrial waste

NASA Astrophysics Data System (ADS)

Canda, L.; Heput, T.; Ardelean, E.

2016-02-01

The accelerated rate of industrialization increases the demand for precious metals, while high quality natural resources are diminished quantitatively, with significant operating costs. Precious metals recovery can be successfully made from waste, considered to be secondary sources of raw material. In recent years, concerns and interest of researchers for more increasing efficient methods to recover these metals, taking into account the more severe environmental protection legislation. Precious metals are used in a wide range of applications, both in electronic and communications equipment, spacecraft and jet aircraft engines and for mobile phones or catalytic converters. The most commonly recovered precious metals are: gold from jewellery and electronics, silver from X- ray films and photographic emulsions, industrial applications (catalysts, batteries, glass/mirrors), jewellery; platinum group metals from catalytic converters, catalysts for the refining of crude oil, industrial catalysts, nitric acid manufacturing plant, the carbon-based catalyst, e-waste. An important aspect is the economic viability of recycling processes related to complex waste flows. Hydrometallurgical and pyrometallurgical routes are the most important ways of processing electrical and electronic equipment waste. The necessity of recovering precious metals has opened new opportunities for future research.

Leachability of heavy metals from growth media containing source-separated municipal solid waste compost

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

Sawhney, B.L.; Bugbee, G.J.; Stilwell, D.E.

1994-07-01

The leaching of heavy metals in source-separated municipal solid waste (MSW) compost was determined by irrigation leaching of growth medium, admixed with varying amounts of compost, used for container grown plants. Perennial flowers (black-eyed Susan, Rudbeckia hirta L.) were grown in 2-L containers filled with the growth medium for a 10-wk period. Rainfall was supplemented with overhead irrigation to supply 2 cm of water per day. Leachates collected over each 2-wk period were analyzed for Cd, Cr, Cu, Ni, Pb, and Zn using atomic spectrometry. Concentrations of the heavy metals in the leachates increased with increasing proportions of MSW compostmore » in the growth medium, but decreased with time of leaching. Leaching of the metals occurred at relatively high concentrations initially, followed by continued leaching at low concentrations. The initial leaching of heavy metals is attributed to their soluble or exchangeable forms and the subsequent slow leaching to the solid compounds. The concentrations of the heavy metals remained below the current drinking water standards in all treatments throughout the leaching period. The results thus suggest that contamination of groundwater with heavy metals from source-separated MSW compost applied as a soil amendment should be negligible, as the low concentrations in the leachates leaving the surface soil would be further attenuated by the subsoil. 29 refs., 6 figs., 1 tab.« less

40 CFR 761.340 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... leaching characteristics for storage or disposal. (a) Existing accumulations of non-liquid, non-metal PCB bulk product waste. (b) Non-liquid, non-metal PCB bulk product waste from processes that continuously generate new waste. (c) Non-liquid PCB remediation waste from processes that continuously generate new...

In situ formation of phosphate barriers in soil

DOEpatents

Moore, Robert C.

2002-01-01

Reactive barriers and methods for making reactive barriers in situ in soil for sequestering soil ontaminants including actinides and heavy metals. The barrier includes phosphate, and techniques are disclosed for forming specifically apatite barriers. The method includes injecting dilute reagents into soil in proximity to a contamination plume or source such as a waste drum to achieve complete or partial encapsulation of the waste. Controlled temperature and pH facilitates rapid formation of apatite, for example, where dilute aqueous calcium chloride and dilute aqueous sodium phosphate are the selected reagents. Mixing of reagents to form precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

Foamed lightweight materials made from mixed scrap metal waste powder and sewage sludge ash.

PubMed

Wang, Kuen-Sheng; Chiou, Ing-Jia

2004-10-01

The porous properties and pozzolanic effects of sewage sludge ash (SSA) make it possible to produce lightweight materials. This study explored the effects of different metallic foaming agents, made from waste aluminium products, on the foaming behaviours and engineering characteristics, as well as the microstructure of sewage sludge ash foamed lightweight materials. The results indicated that aluminium powder and mixed scrap metal waste powder possessed similar chemical compositions. After proper pre-treatment, waste aluminium products proved to be ideal substitutes for metallic foaming agents. Increasing the amount of mixed scrap metal waste by 10-15% compared with aluminium powder would produce a similar foaming ratio and compressive strength. The reaction of the metallic foaming agents mainly produced pores larger than 10 microm, different from the hydration reaction of cement that produced pores smaller than 1 microm mostly. To meet the requirements of the lightweight materials characteristics and the compressive strength, the amount of SSA could be up to 60-80% of the total solids. An adequate amount of aluminium powder is 0.5-0.9% of the total solids. Increasing the fineness of the mixed scrap metal waste powder could effectively reduce the amount required and improve the foaming ratio.

Thermal and hydrometallurgical recovery methods of heavy metals from municipal solid waste fly ash

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

Kuboňová, L., E-mail: lenka.kubonova@vsb.cz; Langová, Š.; Nowak, B.

2013-11-15

Highlights: • MSW fly ash was thermally and hydrometallurgically treated to remove heavy metals. • More than 90% of easy volatile heavy metals (Cd and Pb) were removed thermally. • More than 90% of Cd, Cr, Cu an Zn were removed by alkaline – acid leaching. • The best results were obtained for the solution of 3 M NaOH and 2 M H{sub 2}SO{sub 4}. - Abstract: Heavy metals in fly ash from municipal solid waste incinerators are present in high concentrations. Therefore fly ash must be treated as a hazardous material. On the other hand, it may be amore » potential source of heavy metals. Zinc, lead, cadmium, and copper can be relatively easily removed during the thermal treatment of fly ash, e.g. in the form of chlorides. In return, wet extraction methods could provide promising results for these elements including chromium and nickel. The aim of this study was to investigate and compare thermal and hydrometallurgical treatment of municipal solid waste fly ash. Thermal treatment of fly ash was performed in a rotary reactor at temperatures between 950 and 1050 °C and in a muffle oven at temperatures from 500 to 1200 °C. The removal more than 90% was reached by easy volatile heavy metals such as cadmium and lead and also by copper, however at higher temperature in the muffle oven. The alkaline (sodium hydroxide) and acid (sulphuric acid) leaching of the fly ash was carried out while the influence of temperature, time, concentration, and liquid/solid ratio were investigated. The combination of alkaline-acidic leaching enhanced the removal of, namely, zinc, chromium and nickel.« less

Urinary heavy metal levels and relevant factors among people exposed to e-waste dismantling.

PubMed

Wang, Hongmei; Han, Mei; Yang, Suwen; Chen, Yanqing; Liu, Qian; Ke, Shen

2011-01-01

Primitive electronic waste (e-waste) recycling has become a growing environmental concern, and toxic heavy metals released from e-waste activities may continue to threaten the health of local people. To study the impact of heavy metals in people around e-waste sites, 349 people from e-waste recycling sites (exposure group) and 118 people from a green plantation (control group) were surveyed, and their urinary levels of lead (UPb), cadmium (UCd), manganese (UMn), copper (UCu), and Zinc (UZn) were assayed. Questionnaire surveys for risk factors were also performed and analyzed by using the Pearson correlation analysis. Results indicated that the levels of urinary Cd in both occupational dismantling people {GM(GSD) 0.72(0.71) ug/L} and non-occupational dismantling people {GM(GSD) 0.50(0.79) ug/L} were higher than the control group {GM(GSD) 0.27(0.85) ug/L}. Further analyses of correlations between urinary heavy metal levels and exposure factors in the exposed group revealed positive relationship between the duration of dismantling and the level of UPb (p < 0.05). Meanwhile, rice sources from local village have a positive correlation with the level of UPb and UCd (p < 0.01). Other factors, however, may also have influences on heavy metal burden, and not all urinary heavy metal levels can be contributed to e-waste dismantling exposure levels. Primitive e-waste recycling activities may contribute to the changes of urinary heavy metal levels and increase the health risk for those chronically working on e-waste dismantling. Copyright © 2010 Elsevier Ltd. All rights reserved.

Safe disposal of surplus plutonium

NASA Astrophysics Data System (ADS)

Gong, W. L.; Naz, S.; Lutze, W.; Busch, R.; Prinja, A.; Stoll, W.

2001-06-01

About 150 tons of weapons grade and weapons usable plutonium (metal, oxide, and in residues) have been declared surplus in the USA and Russia. Both countries plan to convert the metal and oxide into mixed oxide fuel for nuclear power reactors. Russia has not yet decided what to do with the residues. The US will convert residues into a ceramic, which will then be over-poured with highly radioactive borosilicate glass. The radioactive glass is meant to provide a deterrent to recovery of plutonium, as required by a US standard. Here we show a waste form for plutonium residues, zirconia/boron carbide (ZrO 2/B 4C), with an unprecedented combination of properties: a single, radiation-resistant, and chemically durable phase contains the residues; billion-year-old natural analogs are available; and criticality safety is given under all conceivable disposal conditions. ZrO 2/B 4C can be disposed of directly, without further processing, making it attractive to all countries facing the task of plutonium disposal. The US standard for protection against recovery can be met by disposal of the waste form together with used reactor fuel.

Assessment of heavy metal contamination in soil due to leachate migration from an open dumping site

NASA Astrophysics Data System (ADS)

Kanmani, S.; Gandhimathi, R.

2013-03-01

The concentration of heavy metals was studied in the soil samples collected around the municipal solid waste (MSW) open dumpsite, Ariyamangalam, Tiruchirappalli, Tamilnadu to understand the heavy metal contamination due to leachate migration from an open dumping site. The dump site receives approximately 400-470 tonnes of municipal solid waste. Solid waste characterization was carried out for the fresh and old municipal solid waste to know the basic composition of solid waste which is dumped in the dumping site. The heavy metal concentration in the municipal solid waste fine fraction and soil samples were analyzed. The heavy metal concentration in the collected soil sample was found in the following order: Mn > Pb > Cu > Cd. The presence of heavy metals in soil sample indicates that there is appreciable contamination of the soil by leachate migration from an open dumping site. However, these pollutants species will continuously migrated and attenuated through the soil strata and after certain period of time they might contaminate the groundwater system if there is no action to be taken to prevent this phenomenon.

Hydrogen generation from caustic aluminum reaction

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

REYNOLDS, D.A.

2001-10-23

A ''crawler'' is to enter the AY farm annulus to clean the metal surface for corrosion measurements. The ''crawler'' weighs about 190 pounds of which 150 pounds are aluminum. (These values are supplied by the vender of the ''crawler''.) There is a potential that cleaning the surface of the metal may cause a leak to occur in the primary tank wall and the waste may contact the aluminum. The hydroxide in the waste may react with the aluminum and form hydrogen gas. The purpose of this analysis is to estimate the rate of hydrogen gas generation and the time tomore » reach the lower flammable limit (LFL) in the annulus. Surface area of the aluminum piece is estimated to be 2 sq.ft. (This value was given by the vender.) SA:= 2 {center_dot} ft{sup 2}.« less

Oil palm biomass as an adsorbent for heavy metals.

PubMed

Vakili, Mohammadtaghi; Rafatullah, Mohd; Ibrahim, Mahamad Hakimi; Abdullah, Ahmad Zuhairi; Salamatinia, Babak; Gholami, Zahra

2014-01-01

Many industries discharge untreated wastewater into the environment. Heavy metals from many industrial processes end up as hazardous pollutants of wastewaters.Heavy metal pollution has increased in recent decades and there is a growing concern for the public health risk they may pose. To remove heavy metal ions from polluted waste streams, adsorption processes are among the most common and effective treatment methods. The adsorbents that are used to remove heavy metal ions from aqueous media have both advantages and disadvantages. Cost and effectiveness are two of the most prominent criteria for choosing adsorbents. Because cost is so important, great effort has been extended to study and find effective lower cost adsorbents.One class of adsorbents that is gaining considerable attention is agricultural wastes. Among many alternatives, palm oil biomasses have shown promise as effective adsorbents for removing heavy metals from wastewater. The palm oil industry has rapidly expanded in recent years, and a large amount of palm oil biomass is available. This biomass is a low-cost agricultural waste that exhibits, either in its raw form or after being processed, the potential for eliminating heavy metal ions from wastewater. In this article, we provide background information on oil palm biomass and describe studies that indicate its potential as an alternative adsorbent for removing heavy metal ions from wastewater. From having reviewed the cogent literature on this topic we are encouraged that low-cost oil-palm-related adsorbents have already demonstrated outstanding removal capabilities for various pollutants.Because cost is so important to those who choose to clean waste streams by using adsorbents, the use of cheap sources of unconventional adsorbents is increasingly being investigated. An adsorbent is considered to be inexpensive when it is readily available, is environmentally friendly, is cost-effective and be effectively used in economical processes. The advantages that oil palm biomass has includes the following:available and exists in abundance, appears to be effective technically, and can be integrated into existing processes. Despite these advantages, oil palm biomasses have disadvantages such as low adsorption capacity, increased COD, BOD and TOC. These disadvantages can be overcome by modifying the biomass either chemically or thermally. Such modification creates a charged surface and increases the heavy metal ion binding capacity of the adsorbent.

Nanoparticles: their potential toxicity, waste and environmental management.

PubMed

Bystrzejewska-Piotrowska, Grazyna; Golimowski, Jerzy; Urban, Pawel L

2009-09-01

This literature review discusses specific issues related to handling of waste containing nanomaterials. The aims are (1) to highlight problems related to uncontrolled release of nanoparticles to the environment through waste disposal, and (2) to introduce the topics of nanowaste and nanotoxicology to the waste management community. Many nanoparticles used by industry contain heavy metals, thus toxicity and bioaccumulation of heavy metals contained in nanoparticles may become important environmental issues. Although bioavailability of heavy metals contained in nanoparticles can be lower than those present in soluble form, the toxicity resulting from their intrinsic nature (e.g. their size, shape or density) may be significant. An approach to the treatment of nanowaste requires understanding of all its properties--not only chemical, but also physical and biological. Progress in nanowaste management also requires studies of the environmental impact of the new materials. The authors believe Amara's law is applicable to the impact of nanotechnologies, and society might overestimate the short-term effects of these technologies, while underestimating the long-term effects. It is necessary to have basic information from companies about the level and nature of nanomaterials produced or emitted and about the expectation of the life cycle time of nanoproducts as a basis to estimate the level of nanowaste in the future. Without knowing how companies plan to use and store recycled and nonrecycled nanomaterials, development of regulations is difficult. Tagging of nanoproducts is proposed as a means to facilitate separation and recovery of nanomaterials.

State-of-the-art of recycling e-wastes by vacuum metallurgy separation.

PubMed

Zhan, Lu; Xu, Zhenming

2014-12-16

In recent era, more and more electric and electronic equipment wastes (e-wastes) are generated that contain both toxic and valuable materials in them. Most studies focus on the extraction of valuable metals like Au, Ag from e-wastes. However, the recycling of metals such as Pb, Cd, Zn, and organics has not attracted enough attentions. Vacuum metallurgy separation (VMS) processes can reduce pollution significantly using vacuum technique. It can effectively recycle heavy metals and organics from e-wastes in an environmentally friendly way, which is beneficial for both preventing the heavy metal contaminations and the sustainable development of resources. VMS can be classified into several methods, such as vacuum evaporation, vacuum carbon reduction and vacuum pyrolysis. This paper respectively reviews the state-of-art of these methods applied to recycling heavy metals and organics from several kinds of e-wastes. The method principle, equipment used, separating process, optimized operating parameters and recycling mechanism of each case are illustrated in details. The perspectives on the further development of e-wastes recycling by VMS are also presented.

Metal leachability, heavy metals, polycyclic aromatic hydrocarbons and polychlorinated biphenyls in fly and bottom ashes of a medical waste incineration facility.

PubMed

Valavanidis, Athanasios; Iliopoulos, Nikiforos; Fiotakis, Konstantinos; Gotsis, George

2008-06-01

Medical waste from hospitals and other healthcare institutions has become an imperative environmental and public safety problem. Medical waste in Greece has become one of the most urgent environmental problems, because there are 14,000 tons produced annually, of which only a small proportion is incinerated. In the prefecture of Attica there is only one modern municipal medical waste incinerator (started 2004) burning selected infectious hospital waste (5-6 tons day(-1)). Fly and bottom residues (ashes) are collected and stored temporarily in barrels. High values of metal leachability prohibit the landfilling of these ashes, as imposed by EU directives. In the present study we determined quantitatively the heavy metals and other elements in the fly and bottom ashes of the medical waste incinerator, by inductively coupled plasma emission spectrometry (ICP) and by energy dispersive X-ray analysis (EDAX). Heavy metals, which are very toxic, such as Pb, Cd, Ni, Cr, Cu and Zn were found in high concentrations in both fly and bottom ashes. Metal leachability of fly and bottom ashes by water and kerosene was measured by ICP and the results showed that toxic metals in both ashes, such as Pb, Cr, Cd, Cu and Zn, have high leaching values. These values indicate that metals can become soluble and mobile if ash is deposited in landfills, thus restricting their burial according to EU regulations. Analysis of polychlorinated biphenyls and polycyclic aromatic hydrocarbons in fly and bottom ashes showed that their concentrations were very low. This is the first known study in Greece and the results showed that incineration of medical waste can be very effective in minimizing the most hazardous and infectious health-care waste. The presence of toxic metals with high leachability values remains an important draw back of incineration of medical waste and various methods of treating these residues to diminish leaching are been considered at present to overcome this serious technical problem.

Prototype Development of Remote Operated Hot Uniaxial Press (ROHUP) to Fabricate Advanced Tc-99 Bearing Ceramic Waste Forms - 13381

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

Alaniz, Ariana J.; Delgado, Luc R.; Werbick, Brett M.

The objective of this senior student project is to design and build a prototype construction of a machine that simultaneously provides the proper pressure and temperature parameters to sinter ceramic powders in-situ to create pellets of rather high densities of above 90% (theoretical). This ROHUP (Remote Operated Hot Uniaxial Press) device is designed specifically to fabricate advanced ceramic Tc-99 bearing waste forms and therefore radiological barriers have been included in the system. The HUP features electronic control and feedback systems to set and monitor pressure, load, and temperature parameters. This device operates wirelessly via portable computer using Bluetooth{sup R} technology.more » The HUP device is designed to fit in a standard atmosphere controlled glove box to further allow sintering under inert conditions (e.g. under Ar, He, N{sub 2}). This will further allow utilizing this HUP for other potential applications, including radioactive samples, novel ceramic waste forms, advanced oxide fuels, air-sensitive samples, metallic systems, advanced powder metallurgy, diffusion experiments and more. (authors)« less

Method for processing aqueous wastes

DOEpatents

Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

1993-12-28

A method is presented for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply. 4 figures.

Recovery of metals and nonmetals from electronic waste by physical and chemical recycling processes.

PubMed

Kaya, Muammer

2016-11-01

This paper reviews the existing and state of art knowledge for electronic waste (e-waste) recycling. Electrical and/or electronic devices which are unwanted, broken or discarded by their original users are known as e-waste. The main purpose of this article is to provide a comprehensive review of e-waste problem, strategies of e-waste management and various physical, chemical and metallurgical e-waste recycling processes, their advantages and disadvantages towards achieving a cleaner process of waste utilization, with special attention towards extraction of both metallic values and nonmetallic substances. The hazards arise from the presence of heavy metals Hg, Cd, Pb, etc., brominated flame retardants (BFRs) and other potentially harmful substances in e-waste. Due to the presence of these substances, e-waste is generally considered as hazardous waste and, if improperly managed, may pose significant human and environmental health risks. This review describes the potential hazards and economic opportunities of e-waste. Firstly, an overview of e-waste/printed circuit board (PCB) components is given. Current status and future perspectives of e-waste/PCB recycling are described. E-waste characterization, dismantling methods, liberation and classification processes are also covered. Manual selective dismantling after desoldering and metal-nonmetal liberation at -150μm with two step crushing are seen to be the best techniques. After size reduction, mainly physical separation processes employing gravity, electrostatic, magnetic separators, froth floatation, etc. have been critically reviewed here for separation of metals and nonmetals, along with useful utilizations of the nonmetallic materials. The recovery of metals from e-waste material after physical separation through pyrometallurgical, hydrometallurgical or biohydrometallurgical routes is also discussed along with purification and refining. Suitable PCB recycling flowsheets for industrial applications are also given. It seems that hydrometallurgical route will be a key player in the base and precious metals recoveries from e-waste. E-waste recycling will be a very important sector in the near future from economic and environmental perspectives. Recycling technology aims to take today's waste and turn it into conflict-free, sustainable polymetallic secondary resources (i.e. Urban Mining) for tomorrow. Recycling technology must ensure that e-waste is processed in an environmentally friendly manner, with high efficiency and lowered carbon footprint, at a fraction of the costs involved with setting multibillion dollar smelting facilities. Taking into consideration our depleting natural resources, this Urban Mining approach offers quite a few benefits. This results in increased energy efficiency and lowers demand for mining of new raw materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Niobate-based octahedral molecular sieves

DOEpatents

Nenoff, Tina M.; Nyman, May D.

2006-10-17

Niobate-based octahedral molecular sieves having significant activity for multivalent cations and a method for synthesizing such sieves are disclosed. The sieves have a net negatively charged octahedral framework, comprising niobium, oxygen, and octahedrally coordinated lower valence transition metals. The framework can be charge balanced by the occluded alkali cation from the synthesis method. The alkali cation can be exchanged for other contaminant metal ions. The ion-exchanged niobate-based octahedral molecular sieve can be backexchanged in acidic solutions to yield a solution concentrated in the contaminant metal. Alternatively, the ion-exchanged niobate-based octahedral molecular sieve can be thermally converted to a durable perovskite phase waste form.

Niobate-based octahedral molecular sieves

DOEpatents

Nenoff, Tina M.; Nyman, May D.

2003-07-22

Niobate-based octahedral molecular sieves having significant activity for multivalent cations and a method for synthesizing such sieves are disclosed. The sieves have a net negatively charged octahedral framework, comprising niobium, oxygen, and octahedrally coordinated lower valence transition metals. The framework can be charge balanced by the occluded alkali cation from the synthesis method. The alkali cation can be exchanged for other contaminant metal ions. The ion-exchanged niobate-based octahedral molecular sieve can be backexchanged in acidic solutions to yield a solution concentrated in the contaminant metal. Alternatively, the ion-exchanged niobate-based octahedral molecular sieve can be thermally converted to a durable perovskite phase waste form.

Quantification of the resource recovery potential of municipal solid waste incineration bottom ashes

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

Allegrini, Elisa, E-mail: elia@env.dtu.dk; Maresca, Alberto; Olsson, Mikael Emil

2014-09-15

Highlights: • Ferrous and non-ferrous metals were quantified in MSWI bottom ashes. • Metal recovery system efficiencies for bottom ashes were estimated. • Total content of critical elements was determined in bottom ash samples. • Post-incineration recovery is not viable for most critical elements. - Abstract: Municipal solid waste incineration (MSWI) plays an important role in many European waste management systems. However, increasing focus on resource criticality has raised concern regarding the possible loss of critical resources through MSWI. The primary form of solid output from waste incinerators is bottom ashes (BAs), which also have important resource potential. Based onmore » a full-scale Danish recovery facility, detailed material and substance flow analyses (MFA and SFA) were carried out, in order to characterise the resource recovery potential of Danish BA: (i) based on historical and experimental data, all individual flows (representing different grain size fractions) within the recovery facility were quantified, (ii) the resource potential of ferrous (Fe) and non-ferrous (NFe) metals as well as rare earth elements (REE) was determined, (iii) recovery efficiencies were quantified for scrap metal and (iv) resource potential variability and recovery efficiencies were quantified based on a range of ashes from different incinerators. Recovery efficiencies for Fe and NFe reached 85% and 61%, respectively, with the resource potential of metals in BA before recovery being 7.2%ww for Fe and 2.2%ww for NFe. Considerable non-recovered resource potential was found in fine fraction (below 2 mm), where approximately 12% of the total NFe potential in the BA were left. REEs were detected in the ashes, but the levels were two or three orders of magnitude lower than typical ore concentrations. The lack of REE enrichment in BAs indicated that the post-incineration recovery of these resources may not be a likely option with current technology. Based on these results, it is recommended to focus on limiting REE-containing products in waste for incineration and improving pre-incineration sorting initiatives for these elements.« less

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation of non-recyclable wastes (e.g., polychlorinated biphenyl... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Waste management plan. 60.55c Section...

Micron-size metal-binding hydrogel particles improve germination and radicle elongation of Australian metallophyte grasses in mine waste rock and tailings.

PubMed

Guterres, J; Rossato, L; Pudmenzky, A; Doley, D; Whittaker, M; Schmidt, S

2013-03-15

Metal contamination of landscapes as a result of mining and other industrial activities is a pervasive problem worldwide. Metal contaminated soils often lack effective vegetation cover and are prone to contaminant leaching and dispersion through erosion, leading to contamination of the environment. Metal-binding hydrogel particle amendments could ameliorate mine wastes prior to planting and enhance seedling emergence. In this study, micron-size thiol functional cross-linked acrylamide polymer hydrogel particles (X3) were synthesised and tested in laboratory-scale experiments on phytotoxic mine wastes to determine their capacity to: (i) increase substrate water holding capacity (WHC); (ii) reduce metal availability to plants to below the phytotoxicity threshold; and (iii) enhance germination characteristics and early radicle development of two Australian metallophyte grasses under limiting and non-limiting water conditions. Addition of X3 to mine wastes significantly increased their WHC and lowered toxic soluble metal concentrations in mine waste leachates. Germination percentages and radicle elongation of both grasses in wastes were significantly increased. Highest germination percentages and greater radicle development recorded in X3 amended wastes under water limited conditions suggests that X3 was able to ameliorate metal toxicity to radicles, and provide moisture, which improved the imbibition and consequent germination of the seeds. Copyright © 2013 Elsevier B.V. All rights reserved.

An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

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

Mauthoor, Sumayya, E-mail: sumayya.mauthoor@umail.uom.ac.mu; Mohee, Romeela; Kowlesser, Prakash

2014-10-15

Highlights: • Scrap metal processing wastes. • Areas of applications for slag, electric arc furnace dust, mill scale and wastewater sludge. • Waste generation factor of 349.3 kg per ton of steel produced. • Waste management model. - Abstract: This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described andmore » an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.« less

The Toxicological Geochemistry of Dusts, Soils, and Other Earth Materials: Insights From In Vitro Physiologically-based Geochemical Leach Tests

NASA Astrophysics Data System (ADS)

Plumlee, G. S.; Ziegler, T. L.; Lamothe, P.; Meeker, G. P.; Sutley, S.

2003-12-01

Exposure to mineral dusts, soils, and other earth materials results in chemical reactions between the materials and different body fluids that include, depending upon the exposure route, lung fluids, gastrointestinal fluids, and perspiration. In vitro physiologically-based geochemical leach tests provide useful insights into these chemical reactions and their potential toxicological implications. We have conducted such leach tests on a variety of earth materials, including asbestos, volcanic ash, dusts from dry lake beds, mine wastes, wastes left from the roasting of mercury ores, mineral processing wastes, coal dusts and coal fly ash, various soils, and complex dusts generated by the World Trade Center collapse. Size-fractionated samples of earth materials that have been well-characterized mineralogically and chemically are reacted at body temperature (37 C) for periods from 2 hours up to multiple days with various proportions of simulated lung, gastric, intestinal, and/or plasma-based fluids. Results indicate that different earth materials may have quite different solubility and dissolution behavior in vivo, depending upon a) the mineralogic makeup of the material, and b) the exposure route. For example, biodurable minerals such as asbestos and volcanic ash particles, whose health effects result because they dissolve very slowly in vivo, bleed off low levels of trace metals into the simulated lung fluids; these include metals such as Fe and Cr that are suspected by health scientists of contributing to the generation of reactive oxygen species and resulting DNA damage in vivo. In contrast, dry lake bed dusts and concrete-rich dusts are highly alkaline and bioreactive, and cause substantial pH increases and other chemical changes in the simulated body fluids. Many of the earth materials tested contain a variety of metals that can be quite soluble (bioaccessible), depending upon the material and the simulated body fluid composition. For example, due to their acidic pH and high chloride concentrations, simulated gastric fluids are most efficient at solubilizing metals such as Hg, Pb, Zn, and others that form strong chloride complexes; although these metals tend to partially reprecipitate in the near-neutral simulated intestinal fluids, complexes with organic ligands (i.e., amino and carboxylic acids) enhance their solubility. These metals are also quite soluble in near-neutral, protein-rich plasma-based fluids because they form strong complexes with the proteins. In contrast, metalloids that form oxyanion species (such as As, Cr, Mo, W) are commonly more soluble in near-neutral pH simulated lung fluids than in simulated gastric fluids.

Modeling the energy content of combustible ship-scrapping waste at Alang-Sosiya, India, using multiple regression analysis.

PubMed

Reddy, M Srinivasa; Basha, Shaik; Joshi, H V; Sravan Kumar, V G; Jha, B; Ghosh, P K

2005-01-01

Alang-Sosiya is the largest ship-scrapping yard in the world, established in 1982. Every year an average of 171 ships having a mean weight of 2.10 x 10(6)(+/-7.82 x 10(5)) of light dead weight tonnage (LDT) being scrapped. Apart from scrapped metals, this yard generates a massive amount of combustible solid waste in the form of waste wood, plastic, insulation material, paper, glass wool, thermocol pieces (polyurethane foam material), sponge, oiled rope, cotton waste, rubber, etc. In this study multiple regression analysis was used to develop predictive models for energy content of combustible ship-scrapping solid wastes. The scope of work comprised qualitative and quantitative estimation of solid waste samples and performing a sequential selection procedure for isolating variables. Three regression models were developed to correlate the energy content (net calorific values (LHV)) with variables derived from material composition, proximate and ultimate analyses. The performance of these models for this particular waste complies well with the equations developed by other researchers (Dulong, Steuer, Scheurer-Kestner and Bento's) for estimating energy content of municipal solid waste.

Applications of fiber reinforced concrete containers in France and in Slovakia

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

Verdier, A.; Delgrande, J.; Remias, V.

Radioactive waste immobilization is an integral part of operations in nuclear facilities. The goal of immobilization is to contain radioactive materials in a waste form which can maintain its integrity over very long periods of time, thus effectively isolating the materials from the environment and hence from the public. This is true regardless of the activity of the waste, including low-, and medium-level waste (LLW, MLW). A multiple-year research effort by COGEMA culminated in the development of a new process to immobilize nuclear waste in concrete containers reinforced with metal fibers. The fiber reinforced concrete containers satisfy all French safetymore » requirements relating to waste immobilization and disposal, and have been certified by ANDRA, the national radioactive waste management agency. The fiber reinforced concrete containers have been fabricated on a production scale since July 1990 by Sogefibre, a jointly-owned subsidiary of SGN and Campaign Generale des Eaux. This technology is being transferred to Slovenske Elektrarne (Slovak Power Plant) to intern the waste produced by Bohunice and Mochovce power plants in cubical fiber reinforced concrete containers.« less

Removal of heavy metals from aqueous waste streams using surface-modified nanosized TiO{sub 2} photocatalysts.

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

Meshkov, N. K.

1998-08-27

Titanium dioxide (TiO{sub 2}) colloidal particles ({approximately}45{angstrom}) whose surfaces were modified with chelating agents for photocatalytic removal of heavy-metal ions and their subsequent reduction to metallic form were investigated. Experiments were performed on nanoparticle TiO{sub 2} colloids derivatized with bidentate and tridentate ligands (thiolactic acid [TLA], cysteine, and alanine [ALA]) in batch mode in a photoreactor with 254nm light. We used catalysts designed and synthesized for selective and efficient removal of Pb and Cu with and without added hole scavenger (methanol). Parallel experiments also have been carried out in the dark to study metal ion adsorption properties. Solutions have beenmore » filtered to remove TiO{sub 2}, and metal particulates. Both the native solution and the metal deposited on the nanocrystalline TiO{sub 2} particles were analyzed. Results demonstrate that for the case of lead, the most effective TiO{sub 2} surface modifier was TLA (>99% Pb(II) removed from solution). Experiments performed to study Cn removal using TiO{sub 2} colloids modified with alanine showed that copper ions were effectively removed and reduced to metallic form in the presence of methanol.« less

Assessment of sanitary landfill leachate characterizations and its impacts on groundwater at Alexandria.

PubMed

Hassan, Ahmed Hossam; Ramadan, Mohamed Hassan

2005-01-01

The total amount of solid waste generated in Alexandria is 2820 tons/d which increases to 3425 tons/day during summer. In the past, 77% of the collected solid wastes was open dumped. The open dumping sites did not have the minimum requirements for pollution control. Following the exacerbation of the problem, the Alexandria Governorate contracted a company to carry out the solid waste management. The contracted company transferred 75% of the daily generated solid wastes to a new constructed sanitary lanfill. The site receives a daily average of 1910 tons. The landfilling is performed by trench method in the form of cells. The produced leachate is discharged into two lined aerated lagoons. The biogas formed from biodegradation of landfilled solid wastes is burned and the produced heat is used for drying the lagoons leachate. The remaining residues are relandfilled. The study aims at assessment of the solid waste sanitary landfill leachate characterization and its impacts on the groundwater. The analysis of the collected data confirms that leachates from the landfill are severely contaminated with organics, salts, and heavy metals. The fluctuations in concentration levels of the different parameters were attributed to aging and thickness of waste layers, stage of decomposition, and re-landfilling of the concentrated residues from the drying lagoons. The concentrations of NH4-N (600 mg/l) indicated that the process of stabilization was still in the initial stages and attributed to the compaction process. The high BOD5 results (28,833 mg/l) indicated that the process of stabilization was in the initial stages which were very slow. The high COD results (45,240 mg/l) can be attributed to the compaction of the wastes which also retards the degradation of the solid wastes. The BOD and COD values indicated clearly severe contamination. The BOD5/COD ratio measured in the current study (0.64) indicated that the leachate of the present study was biodegradable and unstabilized, and required time and favourable conditions for anaerobic biodegradation. Heavy metals were lower compared with what have been observed in other countries. Re-landfilling of the residue after drying the leachate in lagoons and the short time of biodegradation in the landfill site were factors which effected the high strength of most of the parameters concentrations of the leachate. Assessment of groundwater contamination through piezometer wells around the active cells indicated that there was no contamination from the leachate to the groundwater surrounding the site. The study recommended emphasizing the importance of adjusting the biodegradation factors, the monitoring program, the prohibition of disposing heavy metals, determination of the leachate generation rate, and treatment of leachate.

40 CFR 60.52a - Standard for municipal waste combustor metals.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for municipal waste combustor metals. 60.52a Section 60.52a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... September 20, 1994 § 60.52a Standard for municipal waste combustor metals. (a) On and after the date on...

40 CFR 60.52a - Standard for municipal waste combustor metals.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for municipal waste combustor metals. 60.52a Section 60.52a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... September 20, 1994 § 60.52a Standard for municipal waste combustor metals. (a) On and after the date on...

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

Chemical and biological extraction of metals present in E waste: A hybrid technology

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

Pant, Deepak, E-mail: deepakpant1@rediffmail.com; Joshi, Deepika; Upreti, Manoj K.

2012-05-15

Highlights: Black-Right-Pointing-Pointer Hybrid methodology for E waste management. Black-Right-Pointing-Pointer Efficient extraction of metals. Black-Right-Pointing-Pointer Trace metal extraction is possible. - Abstract: Management of metal pollution associated with E-waste is widespread across the globe. Currently used techniques for the extraction of metals from E-waste by using either chemical or biological leaching have their own limitations. Chemical leaching is much rapid and efficient but has its own environmental consequences, even the future prospects of associated nanoremediation are also uncertain. Biological leaching on the other hand is comparatively a cost effective technique but at the same moment it is time consuming and themore » complete recovery of the metal, alone by biological leaching is not possible in most of the cases. The current review addresses the individual issues related to chemical and biological extraction techniques and proposes a hybrid-methodology which incorporates both, along with safer chemicals and compatible microbes for better and efficient extraction of metals from the E-waste.« less

The influence of metal speciation in combustion waste on the efficiency of Cu, Pb, Zn, Cd, Ni and Cr bioleaching in a mixed culture of sulfur-oxidizing and biosurfactant-producing bacteria.

PubMed

Karwowska, Ewa; Wojtkowska, Małgorzata; Andrzejewska, Dorota

2015-12-15

Metal leachability from ash and combustion slag is related to the physico-chemical properties, including their speciation in the waste. Metals speciation is an important factor that influences the efficiency of metal bioleaching from combustion wastes in a mixed culture of acidophilic and biosurfactant-producing bacteria. It was observed that individual metals tended to occur in different fractions, which reflects their susceptibility to bioleaching. Cr and Ni were readily removed from wastes when present with a high fraction bound to carbonates. Cd and Pb where not effectively bioleached when present in high amounts in a fraction bound to organic matter. The best bioleaching results were obtained for power plant slag, which had a high metal content in the exchangeable, bound to carbonates and bound to Fe and Mg oxides fractions- the metal recovery percentage for Zn, Cu and Ni from this waste exceeded 90%. Copyright © 2015 Elsevier B.V. All rights reserved.

Utilization of flotation wastes of copper slag as raw material in cement production.

PubMed

Alp, I; Deveci, H; Süngün, H

2008-11-30

Copper slag wastes, even if treated via processes such as flotation for metal recovery, still contain heavy metals with hazardous properties posing environmental risks for disposal. This study reports the potential use of flotation waste of a copper slag (FWCS) as iron source in the production of Portland cement clinker. The FWCS appears a suitable raw material as iron source containing >59% Fe(2)O(3) mainly in the form of fayalite (Fe(2)SiO(4)) and magnetite (Fe(3)O(4)). The clinker products obtained using the FWCS from the industrial scale trial operations over a 4-month period were characterised for the conformity of its chemical composition and the physico-mechanical performance of the resultant cement products was evaluated. The data collected for the clinker products produced using an iron ore, which is currently used as the cement raw material were also included for comparison. The results have shown that the chemical compositions of all the clinker products including those of FWCS are typical of a Portland cement clinker. The mechanical performance of the standard mortars prepared from the FWCS clinkers were found to be similar to those from the iron ore clinkers with the desired specifications for the industrial cements e.g. CEM I type cements. Furthermore, the leachability tests (TCLP and SPLP) have revealed that the mortar samples obtained from the FWCS clinkers present no environmental problems while the FWCS could act as the potential source of heavy metal contamination. These findings suggest that flotation wastes of copper slag (FWCS) can be readily utilised as cement raw material due to its availability in large quantities at low cost with the further significant benefits for waste management/environmental practices of the FWCS and the reduced production and processing costs for cement raw materials.

Quantification of the resource recovery potential of municipal solid waste incineration bottom ashes.

PubMed

Allegrini, Elisa; Maresca, Alberto; Olsson, Mikael Emil; Holtze, Maria Sommer; Boldrin, Alessio; Astrup, Thomas Fruergaard

2014-09-01

Municipal solid waste incineration (MSWI) plays an important role in many European waste management systems. However, increasing focus on resource criticality has raised concern regarding the possible loss of critical resources through MSWI. The primary form of solid output from waste incinerators is bottom ashes (BAs), which also have important resource potential. Based on a full-scale Danish recovery facility, detailed material and substance flow analyses (MFA and SFA) were carried out, in order to characterise the resource recovery potential of Danish BA: (i) based on historical and experimental data, all individual flows (representing different grain size fractions) within the recovery facility were quantified, (ii) the resource potential of ferrous (Fe) and non-ferrous (NFe) metals as well as rare earth elements (REE) was determined, (iii) recovery efficiencies were quantified for scrap metal and (iv) resource potential variability and recovery efficiencies were quantified based on a range of ashes from different incinerators. Recovery efficiencies for Fe and NFe reached 85% and 61%, respectively, with the resource potential of metals in BA before recovery being 7.2%ww for Fe and 2.2%ww for NFe. Considerable non-recovered resource potential was found in fine fraction (below 2mm), where approximately 12% of the total NFe potential in the BA were left. REEs were detected in the ashes, but the levels were two or three orders of magnitude lower than typical ore concentrations. The lack of REE enrichment in BAs indicated that the post-incineration recovery of these resources may not be a likely option with current technology. Based on these results, it is recommended to focus on limiting REE-containing products in waste for incineration and improving pre-incineration sorting initiatives for these elements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of soil heavy metal pollution caused by e-waste recycling activities and traditional industrial operations.

PubMed

He, Kailing; Sun, Zehang; Hu, Yuanan; Zeng, Xiangying; Yu, Zhiqiang; Cheng, Hefa

2017-04-01

The traditional industrial operations are well recognized as an important source of heavy metal pollution, while that caused by the e-waste recycling activities, which have sprouted in some developing countries, is often overlooked. This study was carried out to compare the status of soil heavy metal pollution caused by the traditional industrial operations and the e-waste recycling activities in the Pearl River Delta, and assess whether greater attention should be paid to control the pollution arising from e-waste recycling activities. Both the total contents and the chemical fractionation of major heavy metals (As, Cr, Cd, Ni, Pb, Cu, and Zn) in 50 surface soil samples collected from the e-waste recycling areas and 20 soil samples from the traditional industrial zones were determined. The results show that the soils in the e-waste recycling areas were mainly polluted by Cu, Zn, As, and Cd, while Cu, Zn, As, Cd, and Pb were the major heavy metals in the soils from the traditional industrial zones. Statistical analyses consistently show that Cu, Cd, Pb, and Zn in the surface soils from both types of sites were contributed mostly by human activities, while As, Cr, and Ni in the soils were dominated by natural background. No clear distinction was found on the pollution characteristic of heavy metals in the surface soils between the e-waste recycling areas and traditional industrial zones. The potential ecological risk posed by heavy metals in the surface soils from both types of sites, which was dominated by that from Cd, ranged from low to moderate. Given the much shorter development history of e-waste recycling and its largely unregulated nature, significant efforts should be made to crack down on illegal e-waste recycling and strengthen pollution control for related activities.

Chemical stabilization of metals in mine wastes by transformed red mud and other iron compounds: laboratory tests.

PubMed

Ardau, C; Lattanzi, P; Peretti, R; Zucca, A

2014-01-01

A series of static and kinetic laboratory-scale tests were designed in order to evaluate the efficacy of transformed red mud (TRM) from bauxite refining residues, commercial zero-valent iron, and synthetic iron (III) hydroxides as sorbents/reagents to minimize the generation of acid drainage and the release of toxic elements from multi-contaminant-laden mine wastes. In particular, in some column experiments the percolation of meteoric water through a waste pile, alternated with periods of dryness, was simulated. Wastes were placed in columns together with sorbents/reagents in three different set-ups: as blended amendment (mixing method), as a bed at the bottom of the column (filtration method), or as a combination of the two previous methods. The filtration methods, which simulate the creation of a permeable reactive barrier downstream of a waste pile, are the most effective, while the use of sorbents/reagents as amendments leads to unsatisfactory results, because of the selective removal of only some contaminants. The efficacy of the filtration method is not significantly affected by the periods of dryness, except for a temporary rise of metal contents in the leachates due to dissolution of soluble salts formed upon evaporation in the dry periods. These results offer original information on advantages/limits in the use of TRM for the treatment of multi-contaminant-laden mine wastes, and represent the starting point for experimentation at larger scale.

Interaction of Heavy Metal Ions with Carbon and Iron Based Particles

PubMed Central

Fialova, Dana; Kremplova, Monika; Melichar, Lukas; Kopel, Pavel; Hynek, David; Adam, Vojtech; Kizek, Rene

2014-01-01

Due to the rapid development of industry and associated production of toxic waste, especially heavy metals, there is a great interest in creating and upgrading new sorption materials to remove these pollutants from the environment. This study aims to determine the effectiveness of different carbon forms (graphene, expanded carbon, multi-wall nanotubes) and paramagnetic particles (Fe2O3) for adsorption of cadmium(II), lead(II), and copper(II) on its surface, with different interaction time from 1 min to 24 h. The main attention is paid to the detection of these metals using differential pulse voltammetry. Based on the obtained results, graphene and Fe2O3 are found to be good candidates for removal of heavy metals from the environment. PMID:28788566

A reactive distillation process for the treatment of LiCl-KCl eutectic waste salt containing rare earth chlorides

NASA Astrophysics Data System (ADS)

Eun, H. C.; Choi, J. H.; Kim, N. Y.; Lee, T. K.; Han, S. Y.; Lee, K. R.; Park, H. S.; Ahn, D. H.

2016-11-01

The pyrochemical process, which recovers useful resources (U/TRU metals) from used nuclear fuel using an electrochemical method, generates LiCl-KCl eutectic waste salt containing radioactive rare earth chlorides (RECl3). It is necessary to develop a simple process for the treatment of LiCl-KCl eutectic waste salt in a hot-cell facility. For this reason, a reactive distillation process using a chemical agent was achieved as a method to separate rare earths from the LiCl-KCl waste salt. Before conducting the reactive distillation, thermodynamic equilibrium behaviors of the reactions between rare earth (Nd, La, Ce, Pr) chlorides and the chemical agent (K2CO3) were predicted using software. The addition of the chemical agent was determined to separate the rare earth chlorides into an oxide form using these equilibrium results. In the reactive distillation test, the rare earth chlorides in LiCl-KCl eutectic salt were decontaminated at a decontamination factor (DF) of more than 5000, and were mainly converted into oxide (Nd2O3, CeO2, La2O3, Pr2O3) or oxychloride (LaOCl, PrOCl) forms. The LiCl-KCl was purified into a form with a very low concentration (<1 ppm) for the rare earth chlorides.

Environmental Management vitrification activities

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

Krumrine, P.H.

1996-05-01

Both the Mixed Waste and Landfill Stabilization Focus Areas as part of the Office of Technology Development efforts within the Department of Energy`s (DOE) Environmental Management (EM) Division have been developing various vitrification technologies as a treatment approach for the large quantities of transuranic (TRU), TRU mixed and Mixed Low Level Wastes that are stored in either landfills or above ground storage facilities. The technologies being developed include joule heated, plasma torch, plasma arc, induction, microwave, combustion, molten metal, and in situ methods. There are related efforts going into development glass, ceramic, and slag waste form windows of opportunity formore » the diverse quantities of heterogeneous wastes needing treatment. These studies look at both processing parameters, and long term performance parameters as a function of composition to assure that developed technologies have the right chemistry for success.« less

Analysis of total metals in waste molding and core sands from ferrous and non-ferrous foundries.

PubMed

Miguel, Roberto E; Ippolito, James A; Leytem, April B; Porta, Atilio A; Banda Noriega, Roxana B; Dungan, Robert S

2012-11-15

Waste molding and core sands from the foundry industry are successfully being used around the world in geotechnical and soil-related applications. Although waste foundry sands (WFSs) are generally not hazardous in nature, relevant data is currently not available in Argentina. This study aimed to quantify metals in waste molding and core sands from foundries using a variety of metal-binder combinations. Metal concentrations in WFSs were compared to those in virgin silica sands (VSSs), surface soils and soil guidance levels. A total analysis for Ag, Al, Ba, Be, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Te, Tl, V, and Zn was conducted on 96 WFSs and 14 VSSs collected from 17 small and medium-sized foundries. The majority of WFSs analyzed, regardless of metal cast and binder type, contained metal concentrations similar to those found in VSSs and native soils. In several cases where alkyd urethane binder was used, Co and Pb concentrations were elevated in the waste sands. Elevated Cr, Mo, Ni, and Tl concentrations associated with VSSs should not be an issue since these metals are bound within the silica sand matrix. Because of the naturally low metal concentrations found in most WFSs examined in this study, they should not be considered hazardous waste, thus making them available for encapsulated and unencapsulated beneficial use applications. Published by Elsevier Ltd.

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

One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. The current plan for waste isolation consists of stacking low-level waste packages on a trench floor, surrounding the stacks with reinforced steel, and encasing these packages in concrete. These concrete-encased waste stacks are expected to vary in size with maximum dimensions of 6.4 m long, 2.7 m wide, and 4 m high. The waste stacks are expectedmore » to have a surrounding minimum thickness of 15 cm of concrete encasement. These concrete-encased waste packages are expected to withstand environmental exposure (solar radiation, temperature variations, and precipitation) until an interim soil cover or permanent closure cover is installed, and to remain largely intact thereafter. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability of the surrounding soil to retard radionuclide migration. The retardation factors for radionuclides contained in the waste packages can be determined from measurements of diffusion coefficients for these contaminants through concrete and fill material. Some of the mobilization scenarios include (1) potential leaching of waste form before permanent closure cover is installed; (2) after the cover installation, long-term diffusion of radionuclides from concrete waste form into surrounding fill material; (3) diffusion of radionuclides from contaminated soils into adjoining concrete encasement and clean fill material. Additionally, the rate 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 suggesting structural and chemical changes to concrete waste forms which may affect contaminant containment and waste form performance. However, continued research is necessitated by the need to understand: the mechanism of contaminant release; the significance of contaminant release pathways; how waste form performance is affected by the full range of environmental conditions within the disposal facility; the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of waste form aging on chemical, physical, and radiological properties, and the associated impact on contaminant release. Recent reviews conducted by the National Academies of Science recognized the efficacy of cementitious materials for waste isolation, but further noted the significant shortcomings in our current understanding and testing protocol for evaluating the performance of various formulations.« less

Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques.

PubMed

Zhu, Yumin; Zhang, Hua; Shao, Liming; He, Pinjing

2015-01-01

Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste (MSW). In this study, we investigated fine particles of <2mm, which are small fractions in MSW but constitute a significant component of the total heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of <10 μm within the fine particles. Zn-Cu, Pb-Fe and Fe-Mn-Cr had significant correlations in terms of spatial distribution. The overlapped enrichment, spatial association, and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions (such as scraps of organic wastes or ceramics) or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction (such as food waste) is a preferable means of facilitating the beneficial utilization of the stabilized products. Copyright © 2014. Published by Elsevier B.V.

SALTSTONE VAULT CLASSIFICATION SAMPLES MODULAR CAUSTIC SIDE SOLVENT EXTRACTION UNIT/ACTINIDE REMOVAL PROCESS WASTE STREAM APRIL 2011

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

Eibling, R.

Savannah River National Laboratory (SRNL) was asked to prepare saltstone from samples of Tank 50H obtained by SRNL on April 5, 2011 (Tank 50H sampling occurred on April 4, 2011) during 2QCY11 to determine the non-hazardous nature of the grout and for additional vault classification analyses. The samples were cured and shipped to Babcock & Wilcox Technical Services Group-Radioisotope and Analytical Chemistry Laboratory (B&W TSG-RACL) to perform the Toxic Characteristic Leaching Procedure (TCLP) and subsequent extract analysis on saltstone samples for the analytes required for the quarterly analysis saltstone sample. In addition to the eight toxic metals - arsenic, barium,more » cadmium, chromium, mercury, lead, selenium and silver - analytes included the underlying hazardous constituents (UHC) antimony, beryllium, nickel, and thallium which could not be eliminated from analysis by process knowledge. Additional inorganic species determined by B&W TSG-RACL include aluminum, boron, chloride, cobalt, copper, fluoride, iron, lithium, manganese, molybdenum, nitrate/nitrite as Nitrogen, strontium, sulfate, uranium, and zinc and the following radionuclides: gross alpha, gross beta/gamma, 3H, 60Co, 90Sr, 99Tc, 106Ru, 106Rh, 125Sb, 137Cs, 137mBa, 154Eu, 238Pu, 239/240Pu, 241Pu, 241Am, 242Cm, and 243/244Cm. B&W TSG-RACL provided subsamples to GEL Laboratories, LLC for analysis for the VOCs benzene, toluene, and 1-butanol. GEL also determines phenol (total) and the following radionuclides: 147Pm, 226Ra and 228Ra. Preparation of the 2QCY11 saltstone samples for the quarterly analysis and for vault classification purposes and the subsequent TCLP analyses of these samples showed that: (1) The saltstone waste form disposed of in the Saltstone Disposal Facility in 2QCY11 was not characteristically hazardous for toxicity. (2) The concentrations of the eight RCRA metals and UHCs identified as possible in the saltstone waste form were present at levels below the UTS. (3) Most of the inorganic species measured in the leachate do not exceed the MCL, SMCL or TW limits. (4) The inorganic waste species that exceeded the MCL by more than a factor of 10 were nitrate, nitrite and the sum of nitrate and nitrite. (5) Analyses met all quality assurance specifications of US EPA SW-846. (6) The organic species (benzene, toluene, 1-butanol, phenol) were either not detected or were less than reportable for the vault classification samples. (7) The gross alpha and radium isotopes could not be determined to the MCL because of the elevated background which raised the detection limits. (8) Most of the beta/gamma activity was from 137Cs and its daughter 137mBa. (9) The concentration of 137Cs and 90Sr were present in the leachate at concentrations 1/40th and 1/8th respectively than in the 2003 vault classification samples. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the SCHWMR R.61-79.261.24(b) RCRA metals requirements for a nonhazardous waste form. The TCLP leachate concentrations for nitrate, nitrite and the sum of nitrate and nitrite were greater than 10x the MCLs in SCDHEC Regulations R.61-107.19, Part I A, which confirms the Saltstone Disposal Facility classification as a Class 3 Landfill. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the R.61-79.268.48(a) non wastewater treatment standards.« less

A New Strategy for Heavy Metal Polluted Environments: A Review of Microbial Biosorbents

PubMed Central

Ayangbenro, Ayansina Segun; Babalola, Olubukola Oluranti

2017-01-01

Persistent heavy metal pollution poses a major threat to all life forms in the environment due to its toxic effects. These metals are very reactive at low concentrations and can accumulate in the food web, causing severe public health concerns. Remediation using conventional physical and chemical methods is uneconomical and generates large volumes of chemical waste. Bioremediation of hazardous metals has received considerable and growing interest over the years. The use of microbial biosorbents is eco-friendly and cost effective; hence, it is an efficient alternative for the remediation of heavy metal contaminated environments. Microbes have various mechanisms of metal sequestration that hold greater metal biosorption capacities. The goal of microbial biosorption is to remove and/or recover metals and metalloids from solutions, using living or dead biomass and their components. This review discusses the sources of toxic heavy metals and describes the groups of microorganisms with biosorbent potential for heavy metal removal. PMID:28106848

Electroplating wastes in marine environments: A case history at Quonset Point, Rhode Island

USGS Publications Warehouse

Eisler, Ronald; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

1995-01-01

All U.S. Navy electroplating and metal-finishing wastes are now required to pass through industrial-wastewater treatment plants and other treatment facilities for the removal of heavy metals and other potentially hazardous materials. In 1984 a total of 235,191 metric tons (t) of electroplating and metal-finishing wastes from 70 U.S. Navy installations - primarily shipyards, aviation depots, air stations, and weapons plants - were treated.1 Electroplating wastes were not always fully treated.

Role of Bioadsorbents in Reducing Toxic Metals

PubMed Central

Jaishankar, Monisha; Biju, Vinai George; Krishnamurthy Nideghatta Beeregowda

2016-01-01

Industrialization and urbanization have led to the release of increasing amounts of heavy metals into the environment. Metal ion contamination of drinking water and waste water is a serious ongoing problem especially with high toxic metals such as lead and cadmium and less toxic metals such as copper and zinc. Several biological materials have attracted many researchers and scientists as they offer both cheap and effective removal of heavy metals from waste water. Therefore it is urgent to study and explore all possible sources of agrobased inexpensive adsorbents for their feasibility in the removal of heavy metals. The objective was to study inexpensive adsorbents like various agricultural wastes such as sugarcane bagasse, rice husk, oil palm shell, coconut shell, and coconut husk in eliminating heavy metals from waste water and their utilization possibilities based on our research and literature survey. It also shows the significance of developing and evaluating new potential biosorbents in the near future with higher adsorption capacity and greater reusable options. PMID:28090207

Role of Bioadsorbents in Reducing Toxic Metals.

PubMed

Mathew, Blessy Baby; Jaishankar, Monisha; Biju, Vinai George; Krishnamurthy Nideghatta Beeregowda

2016-01-01

Industrialization and urbanization have led to the release of increasing amounts of heavy metals into the environment. Metal ion contamination of drinking water and waste water is a serious ongoing problem especially with high toxic metals such as lead and cadmium and less toxic metals such as copper and zinc. Several biological materials have attracted many researchers and scientists as they offer both cheap and effective removal of heavy metals from waste water. Therefore it is urgent to study and explore all possible sources of agrobased inexpensive adsorbents for their feasibility in the removal of heavy metals. The objective was to study inexpensive adsorbents like various agricultural wastes such as sugarcane bagasse, rice husk, oil palm shell, coconut shell, and coconut husk in eliminating heavy metals from waste water and their utilization possibilities based on our research and literature survey. It also shows the significance of developing and evaluating new potential biosorbents in the near future with higher adsorption capacity and greater reusable options.

Integrating bioavailability approaches into waste rock evaluations

USGS Publications Warehouse

Ranville, James F.; Blumenstein, E. P.; Adams, Michael J.; Choate, LaDonna M.; Smith, Kathleen S.; Wildeman, Thomas R.

2006-01-01

The presence of toxic metals in soils affected by mining, industry, agriculture and urbanization, presents problems to human health, the establishment and maintenance of plant and animal habitats, and the rehabilitation of affected areas. A key to managing these problems is predicting the fraction of metal in a given soil that will be biologically labile, and potentially harmful ('bioavailable'). The molecular form of metals and metalloids, particularly the uncomplexed (free) form, controls their bioavailability and toxicity in solution. One computational approach for determining bioavailability, the biotic ligand model (BLM), takes into account not only metal complexation by ligands in solution, but also competitive binding of hardness cations (Ca 2+,Mg 2+,) and metal ions to biological receptor sites. The more direct approach to assess bioavailability is to explicitly measure the response of an organism to a contaminant. A number of microbial enzyme tests have been developed to assess the impact of pollution in a rapid and procedurally simple way. These different approaches in making bioavailability predictions may have value in setting landuse priorities, remediation goals, and habitat reclamation strategies.

Pollution distribution of heavy metals in surface soil at an informal electronic-waste recycling site.

PubMed

Fujimori, Takashi; Takigami, Hidetaka

2014-02-01

We studied distribution of heavy metals [lead (Pb), copper (Cu) and zinc (Zn)] in surface soil at an electronic-waste (e-waste) recycling workshop near Metro Manila in the Philippines to evaluate the pollution size (spot size, small area or the entire workshop), as well as to assess heavy metal transport into the surrounding soil environment. On-site length-of-stride-scale (~70 cm) measurements were performed at each surface soil point using field-portable X-ray fluorescence (FP-XRF). The surface soil at the e-waste recycling workshop was polluted with Cu, Zn and Pb, which were distributed discretely in surface soil. The site was divided into five areas based on the distance from an entrance gate (y-axis) of the e-waste recycling workshop. The three heavy metals showed similar concentration gradients in the y-axis direction. Zn, Pb and Cu concentrations were estimated to decrease to half of their maximum concentrations at ~3, 7 and 7 m from the pollution spot, respectively, inside the informal e-waste recycling workshop. Distance from an entrance may play an important role in heavy metal transport at the soil surface. Using on-site FP-XRF, we evaluated the metal ratio to characterise pollution features of the solid surface. Variability analysis of heavy metals revealed vanishing surficial autocorrelation over metre ranges. Also, the possibility of concentration prediction at unmeasured points using geostatistical kriging was evaluated, and heavy metals had a relative "small" pollution scales and remained inside the original workshop compared with toxic organohalogen compounds. Thus, exposure to heavy metals may directly influence the health of e-waste workers at the original site rather than the surrounding habitat and environmental media.

10 CFR Appendix I to Part 110 - Illustrative List of Reprocessing Plant Components Under NRC Export Licensing Authority

Code of Federal Regulations, 2014 CFR

2014-01-01

... dissolution, solvent extraction, and process liquor storage. There may also be equipment for thermal denitration of uranium nitrate, conversion of plutonium nitrate to oxide metal, and treatment of fission product waste liquor to a form suitable for long term storage or disposal. However, the specific type and...

10 CFR Appendix I to Part 110 - Illustrative List of Reprocessing Plant Components Under NRC Export Licensing Authority

Code of Federal Regulations, 2013 CFR

2013-01-01

... dissolution, solvent extraction, and process liquor storage. There may also be equipment for thermal denitration of uranium nitrate, conversion of plutonium nitrate to oxide metal, and treatment of fission product waste liquor to a form suitable for long term storage or disposal. However, the specific type and...

10 CFR Appendix I to Part 110 - Illustrative List of Reprocessing Plant Components Under NRC Export Licensing Authority

Code of Federal Regulations, 2012 CFR

2012-01-01

... dissolution, solvent extraction, and process liquor storage. There may also be equipment for thermal denitration of uranium nitrate, conversion of plutonium nitrate to oxide metal, and treatment of fission product waste liquor to a form suitable for long term storage or disposal. However, the specific type and...

Impeding 99Tc(IV) mobility in novel waste forms

PubMed Central

Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; Kruger, Albert A.; Lukens, Wayne W.; Rousseau, Roger; Glezakou, Vassiliki-Alexandra

2016-01-01

Technetium (99Tc) is an abundant, long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state. Tc immobilization is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels has been proposed as a novel method to increase Tc retention in glass waste forms during vitrification. However, experiments under high-temperature and oxic conditions show reoxidation of Tc(IV) to volatile pertechnetate, Tc(VII). Here we examine this problem with ab initio molecular dynamics simulations and propose that, at elevated temperatures, doping with first row transition metal can significantly enhance Tc retention in magnetite in the order Co>Zn>Ni. Experiments with doped spinels at 700 °C provide quantitative confirmation of the theoretical predictions in the same order. This work highlights the power of modern, state-of-the-art simulations to provide essential insights and generate theory-inspired design criteria of complex materials at elevated temperatures. PMID:27357121

Principles of Product Quality Control of German Radioactive Waste Forms from the Reprocessing of Spent Fuel: Vitrification, Compaction and Numerical Simulation - 12529

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

Tietze-Jaensch, Holger; Schneider, Stephan; Aksyutina, Yuliya

2012-07-01

The German product quality control is inter alia responsible for control of two radioactive waste forms of heat generating waste: a) homogeneous vitrified HLW and b) heterogeneous compacted hulls, end-pieces and technological metallic waste. In either case, significantly different metrology is employed at the site of the conditioning plant for the obligatory nuclide inventory declaration. To facilitate an independent evaluation and checking of the accompanying documentation numerical simulations are carried out. The physical and chemical properties of radioactive waste residues are used to assess the data consistency and uncertainty margins, as well as to predict the long-term behavior of themore » radioactive waste. This is relevant for repository acceptance and safety considerations. Our new numerical approach follows a bottom-up simulation starting from the burn-up behavior of the fuel elements in the reactor core. The output of these burn-up calculations is then coupled with a program that simulates the material separation in the subsequent dissolution and extraction processes normalized to the mass balance. Follow-up simulations of the separated reprocessing lines of a) the vitrification of highly-active liquid and b) the compaction of residual intermediate-active metallic hulls remaining after fuel pellets dissolution, end-pieces and technological waste, allows calculating expectation values for the various repository relevant properties of either waste stream. The principles of the German product quality control of radioactive waste residues from the spent fuel reprocessing have been introduced and explained. Namely, heat generating homogeneous vitrified HLW and heterogeneous compacted metallic MLW have been discussed. The advantages of a complementary numerical property simulation have been made clear and examples of benefits are presented. We have compiled a new program suite to calculate the physical and radio-chemical properties of common nuclear waste residues. The immediate benefit is the independent assessment of radio-active inventory declarations and much facilitated product quality control of waste residues that need to be returned to Germany and submitted to a German HLW-repository requirements. Wherever possible, internationally accepted standard programs are used and embedded. The innovative coupling of burn-up calculations (SCALE) with neutron and gamma transport codes (MCPN-X) allows an application in the world of virtual waste properties. If-then-else scenarios of hypothetical waste material compositions and distributions provide valuable information of long term nuclide property propagation under repository conditions over a very long time span. Benchmarking the program with real residue data demonstrates the power and remarkable accuracy of this numerical approach, boosting the reliability of the confidence aforementioned numerous applications, namely the proof tool set for on-the-spot production quality checking and data evaluation and independent verification. Moreover, using the numerical bottom-up approach helps to avoid the accumulation of fake activities that may gradually build up in a repository from the so-called conservative or penalizing nuclide inventory declarations. The radioactive waste properties and the hydrolytic and chemical stability can be predicted. The interaction with invasive chemicals can be assessed and propagation scenarios can be developed from reliable and sound data and HLW properties. Hence, the appropriate design of a future HLW repository can be based upon predictable and quality assured waste characteristics. (authors)« less

Waste Minimization Study on Pyrochemical Reprocessing Processes

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

Boussier, H.; Conocar, O.; Lacquement, J.

2006-07-01

Ideally a new pyro-process should not generate more waste, and should be at least as safe and cost effective as the hydrometallurgical processes currently implemented at industrial scale. This paper describes the thought process, the methodology and some results obtained by process integration studies to devise potential pyro-processes and to assess their capability of achieving this challenging objective. As example the assessment of a process based on salt/metal reductive extraction, designed for the reprocessing of Generation IV carbide spent fuels, is developed. Salt/metal reductive extraction uses the capability of some metals, aluminum in this case, to selectively reduce actinide fluoridesmore » previously dissolved in a fluoride salt bath. The reduced actinides enter the metal phase from which they are subsequently recovered; the fission products remain in the salt phase. In fact, the process is not so simple, as it requires upstream and downstream subsidiary steps. All these process steps generate secondary waste flows representing sources of actinide leakage and/or FP discharge. In aqueous processes the main solvent (nitric acid solution) has a low boiling point and evaporate easily or can be removed by distillation, thereby leaving limited flow containing the dissolved substance behind to be incorporated in a confinement matrix. From the point of view of waste generation, one main handicap of molten salt processes, is that the saline phase (fluoride in our case) used as solvent is of same nature than the solutes (radionuclides fluorides) and has a quite high boiling point. So it is not so easy, than it is with aqueous solutions, to separate solvent and solutes in order to confine only radioactive material and limit the final waste flows. Starting from the initial block diagram devised two years ago, the paper shows how process integration studies were able to propose process fittings which lead to a reduction of the waste variety and flows leading at an 'ideal' new block diagram allowing internal solvent recycling, and self eliminating reactants. This new flowsheet minimizes the quantity of inactive inlet flows that would have inevitably to be incorporated in a final waste form. The study identifies all knowledge gaps to be filled and suggest some possible R and D issues to confirm or infirm the feasibility of the proposed process fittings. (authors)« less

Thermal Pretreatment For TRU Waste Sorting

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

Sasaki, T.; Aoyama, Y.; Miyamoto, Y.

2008-07-01

Japan Atomic Energy Agency conducted a study on thermal treatment of TRU waste to develop a removal technology for materials that are forbidden for disposal. The thermal pretreatment in which hot nitrogen and/or air is introduced to the waste is a process of removing combustibles, liquids, and low melting point metals from PVC wrapped TRU waste. In this study, thermal pretreatment of simulated waste was conducted using a desktop thermal treatment vessel and a laboratory scale thermal pretreatment system. Combustibles and low melting point metals are effectively separated from wastes by choosing appropriate temperature of flowing gases. Combustibles such asmore » papers, PVC, oil, etc. were removed and low melting point metals such as zinc, lead, and aluminum were separated from the simulated waste by the thermal pretreatment. (authors)« less

Introduction to Exide Corporations`s high temperature metals recovery system

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

Rozelle, P.L.; Baranski, J.P.; Bitler, J.A.

1995-12-31

Environmental strategies concerning the processing and ultimate fate of wastes and byproducts are of ever increasing importance to the public and business sectors in the world today. Recycling materials and reusing energy from wastes and byproducts results in a reduction of environmental impacts and the cost of disposal. These are the key steps in reaching the ultimate goal of waste minimization. In response to these needs, Exide Corporation, in its vision to develop waste minimization programs, has developed the Exide High Temperature Metals Recovery (EHTMR) process. This process can treat a variety of wastes and byproducts where metals contents aremore » an issue, recover the metal values for reuse, and produce a metals-depleted slag that can be marketable under the most stringent proposed EPA regulations for leachability of contaminants. The central feature of the EHTMR process is the exposure of treated materials to a transferred arc plasma generated in an electric furnace. The process achieves a reduction in costs and liability by recovering portions of a waste that can be recycled or reclaimed and produces a slag that has beneficial use to society.« 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

Today's challange in MSW incineration

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

Vaux, W.G.

A decade ago, incinerator ash was of little concern. There wasn't much of it, and it was treated like soil of fill and therefore disposed of without much concern. Today, however, the situation is far different. Waste-to-energy plants reduce the amount of trash they process by 90%, but they require environmentally sound landfills to dispose of residue. This paper examines the management of incinerator ash. At its best, incinerator ash is well burned out; at worst, it is more pyrolized and contains unburned carbon. This latter case is likely following receipt of rain-saturated waste at the incinerator. Ash contains aboutmore » 15 to 20 weight of unburnables; for example metal cans, ceramics, other metals and so on. According to the author, recent work on presence of combustion products in the ash does not show appreciable levels of dioxins leaching form ash.« less

Nonhazardous solvent composition and method for cleaning metal surfaces

DOEpatents

Googin, John M.; Simandl, Ronald F.; Thompson, Lisa M.

1993-01-01

A solvent composition for displacing greasy and oily contaminants as well as water and/or aqueous residue from metallic surfaces, especially surfaces of radioactive materials so that such surfaces can be wiped clean of the displaced contaminants, water and/or aqueous residue. The solvent composition consists essentially of a blend of nonpolar aliphatic hydrocarbon solvent having a minimum flash point of about 140.degree. F. and 2 to 25 volume percent of a polar solvent having a flash point sufficiently high so as to provide the solvent composition with a minimum flash point of at least 140.degree. F. The solvent composition is nonhazardous so that when it is used to clean the surfaces of radioactive materials the waste in the form of paper or cloth wipes, lab coats and the like used in the cleaning operation is not considered to be mixed waste composed of a hazardous solvent and a radioactive material.

Nonhazardous solvent composition and method for cleaning metal surfaces

DOEpatents

Googin, J.M.; Simandl, R.F.; Thompson, L.M.

1993-05-04

A solvent composition for displacing greasy and oily contaminants as well as water and/or aqueous residue from metallic surfaces, especially surfaces of radioactive materials so that such surfaces can be wiped clean of the displaced contaminants, water and/or aqueous residue. The solvent composition consists essentially of a blend of nonpolar aliphatic hydrocarbon solvent having a minimum flash point of about 140 F and 2 to 25 volume percent of a polar solvent having a flash point sufficiently high so as to provide the solvent composition with a minimum flash point of at least 140 F. The solvent composition is nonhazardous so that when it is used to clean the surfaces of radioactive materials the waste in the form of paper or cloth wipes, lab coats and the like used in the cleaning operation is not considered to be mixed waste composed of a hazardous solvent and a radioactive material.

Method for solidification of radioactive and other hazardous waste

DOEpatents

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

2002-01-01

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

Quantification and classification of ship scraping waste at Alang-Sosiya, India.

PubMed

Srinivasa Reddy, M; Basha, Shaik; Sravan Kumar, V G; Joshi, H V; Ghosh, P K

2003-12-01

Alang-Sosiya located on the Western Coast of Gulf of Cambay, is the largest ship recycling yard in the world. Every year on average 365 ships having a mean weight (2.10x10(6)+/-7.82x10(5) LDT) are scrapped. This industry generates a huge quantity of solid waste in the form of broken wood, rubber, insulation materials, paper, metals, glass and ceramics, plastics, leather, textiles, food waste, chemicals, paints, thermocol, sponge, ash, oil mixed sponges, miscellaneous combustible and non-combustible. The quantity and composition of solid waste was collected for a period of three months and the average values are presented in this work. Sosiya had the most waste 15.63 kg/m(2) compared to Alang 10.19 kg/m(2). The combustible solid waste quantity was around 83.0% of the total solid waste available at the yard, which represents an average weight of 9.807 kg/m(2); whereas, non-combustible waste is 1.933 kg/m(2). There is not much difference between the average of total solid waste calculated from the sampling data (96.71 MT/day) and the data provided by the port authorities (96.8 MT/day).

Effect of chemical pretreatment on pyrolysis of non-metallic fraction recycled from waste printed circuit boards.

PubMed

Shen, Yafei

2018-06-01

The non-metallic fraction from waste printed circuit boards (NMF-WPCB) generally consists of plastics with high content of Br, glass fibers and metals (e.g. Cu), which are normally difficult to dispose. This work aims to study the chemical pretreatments by using alkalis, acids and alkali-earth-metal salts on pyrolysis of NMF-WPCB. Char (60-79%) and volatile matter (21-40%) can be produced via the pyrolysis process. In particular, the ash content can reach up to 42-56%, which was attributed to the high content of glass fibers and other minerals. Copper (Cu, 2.5%), calcium (Ca, 28.7%), and aluminum (Al, 6.9%) were the main metal constituents. Meanwhile, silicon (Si, 28.3%) and bromine (Br, 26.4%) were the predominant non-metallic constituents. The heavy metals such as Cu were significantly reduced by 92.4% with the acid (i.e. HCl) pretreatment. It has been proved that the organic Br in the plastics (e.g. BFR) can be transformed into HBr via the pyrolysis process at relatively high temperature. It was noteworthy that the alkali pretreatment was more benefit for the Br fixation in the solid char. Particularly, the Br fixation efficiency can reach up to 53.6% by the sodium hydroxide (NaOH) pretreatment with the pyrolysis process. The formed HBr can react with NaOH to generate NaBr. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preparation of hierarchical porous carbon from waste printed circuit boards for high performance electric double-layer capacitors

NASA Astrophysics Data System (ADS)

Du, Xuan; Wang, Li; Zhao, Wei; Wang, Yi; Qi, Tao; Li, Chang Ming

2016-08-01

Renewable clean energy and resources recycling have become inevitable choices to solve worldwide energy shortages and environmental pollution problems. It is a great challenge to recycle tons of waste printed circuit boards (PCB) produced every year for clean environment while creating values. In this work, low cost, high quality activated carbons (ACs) were synthesized from non-metallic fractions (NMF) of waste PCB to offer a great potential for applications of electrochemical double-layer capacitors (EDLCs). After recovering metal from waste PCB, hierarchical porous carbons were produced from NMF by carbonization and activation processes. The experimental results exhibit that some pores were formed after carbonization due to the escape of impurity atoms introduced by additives in NMF. Then the pore structure was further tailored by adjusting the activation parameters. Roles of micropores and non-micropores in charge storage were investigated when the hierarchical porous carbons were applied as electrode of EDLCs. The highest specific capacitance of 210 F g-1 (at 50 mA g-1) and excellent rate capability were achieved when the ACs possessing a proper micropores/non-micropores ratio. This work not only provides a promising method to recycle PCB, but also investigates the structure tailoring arts for a rational hierarchical porous structure in energy storage/conversion.

Environmentally Benign, Rapid, and Selective Extraction of Gold from Ores and Waste Electronic Materials.

PubMed

Yue, Chunlin; Sun, Huaming; Liu, Wen-Jing; Guan, Binbin; Deng, Xudong; Zhang, Xu; Yang, Peng

2017-08-01

The extraction of gold from ores and electronic waste is an important topic worldwide, as this precious metal has immense value in a variety of fields. However, serious environmental pollution and high energy consumption due to the use of toxic oxidation reagents and harsh reaction conditions is a well-known problem in the gold industry. Herein, we report a new chemical method based on the combined use of N-bromosuccinimide (NBS) and pyridine (Py), which has a greatly decreased environmental impact and reagent cost, as well as mild reaction requirements. This method can directly leach Au 0 from gold ore and electronic waste to form Au III in water. The process is achieved in a yield of approximately 90 % at room temperature and a nearly neutral pH. The minimum dose of NBS/Py is as low as 10 mm, which exhibits low toxicity towards mammalian cells and animals as well as aquatic creatures. The high leaching selectivity of Au over other metals during gold leaching is demonstrated, showing that this method has great potential for practical industrial application towards the sustainable refining of gold from ores and electronic waste. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inventory of heavy metal content in organic waste applied as fertilizer in agriculture: evaluating the risk of transfer into the food chain.

PubMed

Lopes, Carla; Herva, Marta; Franco-Uría, Amaya; Roca, Enrique

2011-07-01

In this work, an environmental risk assessment of reusing organic waste of differing origins and raw materials as agricultural fertilizers was carried out. An inventory of the heavy metal content in different organic wastes (i.e., compost, sludge, or manure) from more than 80 studies at different locations worldwide is presented. The risk analysis was developed by considering the heavy metal (primarily Cd, Cu, Ni, Pb, and Zn) concentrations in different organic residues to assess their potential environmental accumulation and biotransfer to the food chain and humans. A multi-compartment model was used to estimate the fate and distribution of metals in different environmental compartments, and a multi-pathway model was used to predict human exposure. The obtained hazard index for each waste was concerning in many cases, especially in the sludge samples that yielded an average value of 0.64. Among the metals, Zn was the main contributor to total risk in all organic wastes due to its high concentration in the residues and high biotransfer potential. Other more toxic metals, like Cd or Pb, represented a negligible contribution. These results suggest that the Zn content in organic waste should be reduced or more heavily regulated to guarantee the safe management and reuse of waste residues according to the current policies promoted by the European Union.

Organochlorines in surface soil at electronic-waste wire burning sites and metal contribution evaluated using quantitative X-ray speciation

NASA Astrophysics Data System (ADS)

Fujimori, Takashi; Takigami, Hidetaka; Takaoka, Masaki

2013-04-01

Heavy metals and toxic chlorinated aromatic compounds (aromatic-Cls) such as dioxins and polychlorinated biphenyls (PCBs) are found at high concentrations and persist in surface soil at wire burning sites (WBSs) in developing countries in which various wire cables are recycled to yield pure metals. Chlorine K-edge near-edge X-ray absorption fine structure (NEXAFS) is used to detect the specific chemical form of Cl and estimate its amount using a spectrum jump in the solid phase. Quantitative X-ray speciation of Cl was applied to study the mechanisms of aromatic-Cls formation in surface soil at WBSs in Southeast Asia. Relationships between aromatic-Cls and chlorides of heavy metals were evaluated because heavy metals are promoters of the thermochemical solid-phase formation of aromatic-Cls.

Bacteria in Nanoparticle Synthesis: Current Status and Future Prospects

PubMed Central

2014-01-01

Microbial metal reduction can be a strategy for remediation of metal contaminations and wastes. Bacteria are capable of mobilization and immobilization of metals and in some cases, the bacteria which can reduce metal ions show the ability to precipitate metals at nanometer scale. Biosynthesis of nanoparticles (NPs) using bacteria has emerged as rapidly developing research area in green nanotechnology across the globe with various biological entities being employed in synthesis of NPs constantly forming an impute alternative for conventional chemical and physical methods. Optimization of the processes can result in synthesis of NPs with desired morphologies and controlled sizes, fast and clean. The aim of this review is, therefore, to make a reflection on the current state and future prospects and especially the possibilities and limitations of the above mentioned bio-based technique for industries. PMID:27355054

Geochemical and mineralogical controls on metal(loid) mobility in the oxide zone of the Prairie Creek Deposit, NWT

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

Stavinga, Drew; Jamieson, Heather; Layton-Matthews, Daniel

2017-02-01

Prairie Creek is an unmined high grade Zn-Pb-Ag deposit in the southern Mackenzie Mountains of the Northwest Territories, located in a 320 km2 enclave surrounded by the Nahanni National Park reserve. The upper portion of the quartz-carbonate-sulphide vein mineralization has undergone extensive oxidation, forming high grade zones, rich in smithsonite (ZnCO3) and cerussite (PbCO3). This weathered zone represents a significant resource and a potential component of mine waste material. This study is focused on characterizing the geochemical and mineralogical controls on metal(loid) mobility under mine waste conditions, with particular attention to the metal carbonates as a potential source of tracemore » elements to the environment. Analyses were conducted using a combination of microanalytical techniques (electron microprobe, scanning electron microscopy with automated mineralogy, laser-ablation inductively-coupled mass spectrometry, and synchrotron-based element mapping, micro-X-ray diffraction and micro-X-ray absorbance). The elements of interest included Zn, Pb, Ag, As, Cd, Cu, Hg, Sb and Se.« less

Effect of Particulate Matter Mineral Composition on Environmentally Persistent Free Radical (EPFR) Formation.

PubMed

Feld-Cook, Elisabeth E; Bovenkamp-Langlois, Lisa; Lomnicki, Slawo M

2017-09-19

Environmentally Persistent Free Radicals (EPFRs) are newly discovered, long-lived surface bound radicals that form on particulate matter and combustion borne particulates, such as fly ash. Human exposure to such particulates lead to translocation into the lungs and heart resulting in cardio-vascular and respiratory disease through the production of reactive oxygen species. Analysis of some waste incinerator fly ashes revealed a significant difference between their EPFR contents. Although EPFR formation occurs on the metal domains, these differences were correlated with the altering concentration of calcium and sulfur. To analyze these phenomena, surrogate fly ashes were synthesized to mimic the presence of their major mineral components, including metal oxides, calcium, and sulfur. The results of this study led to the conclusion that the presence of sulfates limits formation of EPFRs due to inhibition or poisoning of the transition metal active sites necessary for their formation. These findings provide a pathway toward understanding differences in EPFR presence on particulate matter and uncover the possibility of remediating EPFRs from incineration and hazardous waste sites.

Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

PubMed

Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

2014-11-01

Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

40 CFR 60.52a - Standard for municipal waste combustor metals.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Municipal Waste Combustors for Which Construction Is Commenced After December 20, 1989 and On or Before September 20, 1994 § 60.52a Standard for municipal waste combustor metals. (a) On and after the date on... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for municipal waste combustor...

Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

PubMed

Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

2014-12-01

Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals. Copyright © 2014. Published by Elsevier Ltd.

Radioactive waste material disposal

DOEpatents

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

1995-10-24

The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

Radioactive waste material disposal

DOEpatents

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

1995-01-01

The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

Assessment of mobility and bioavailability of contaminants in MSW incineration ash with aquatic and terrestrial bioassays.

PubMed

Ribé, V; Nehrenheim, E; Odlare, M

2014-10-01

Incineration of municipal solid waste (MSW) is a waste treatment method which can be sustainable in terms of waste volume reduction as well as a source of renewable energy. In the process fly and bottom ash is generated as a waste material. The ash residue may vary greatly in composition depending on the type of waste incinerated and it can contain elevated levels of harmful contaminants such as heavy metals. In this study, the ecotoxicity of a weathered, untreated incineration bottom ash was characterized as defined by the H14 criterion of the EU Waste Framework Directive by means of an elemental analysis, leaching tests followed by a chemical analysis and a combination of aquatic and solid-phase bioassays. The experiments were conducted to assess the mobility and bioavailability of ash contaminants. A combination of aquatic and terrestrial bioassays was used to determine potentially adverse acute effects of exposure to the solid ash and aqueous ash leachates. The results from the study showed that the bottom ash from a municipal waste incineration plant in mid-Sweden contained levels of metals such as Cu, Pb and Zn, which exceeded the Swedish EPA limit values for inert wastes. The chemical analysis of the ash leachates showed high concentrations of particularly Cr. The leachate concentration of Cr exceeded the limit value for L/S 10 leaching for inert wastes. Filtration of leachates prior to analysis may have underestimated the leachability of complex-forming metals such as Cu and Pb. The germination test of solid ash and ash leachates using T. repens showed a higher inhibition of seedling emergence of seeds exposed to the solid ash than the seeds exposed to ash leachates. This indicated a relatively low mobility of toxicants from the solid ash into the leachates, although some metals exceeded the L/S 10 leaching limit values for inert wastes. The Microtox® toxicity test showed only a very low toxic response to the ash leachate exposure, while the D. magna immobility test showed a moderately high toxic effect of the ash leachates. Overall, the results from this study showed an ecotoxic effect of the solid MSW bottom ash and the corresponding ash leachates. The material may therefore pose an environmental risk if used in construction applications. However, as the testing of the solid ash was rather limited and the ash leachate showed an unusually high leaching of Cr, further assessments are required in order to conclusively characterize the bottom ash studied herein as hazardous according to the H14 criterion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nanopore reactive adsorbents for the high-efficiency removal of waste species

DOEpatents

Yang, Arthur Jing-Min; Zhang, Yuehua

2005-01-04

A nanoporous reactive adsorbent incorporates a relatively small number of relatively larger reactant, e.g., metal, enzyme, etc., particles (10) forming a discontinuous or continuous phase interspersed among and surrounded by a continuous phase of smaller adsorbent particles (12) and connected interstitial pores (14) therebetween. The reactive adsorbent can effectively remove inorganic or organic impurities in a liquid by causing the liquid to flow through the adsorbent. For example, silver ions may be adsorbed by the adsorbent particles (12) and reduced to metallic silver by reducing metal, such as ions, as the reactant particles (10). The column can be regenerated by backwashing with the liquid effluent containing, for example, acetic acid.

Speciation and Characterization of E-Waste, Using Analytical Techniques

NASA Astrophysics Data System (ADS)

López, C. Cortés; Cruz, V. E. Reyes; Rodríguez, M. A. Veloz; Ávila, J. Hernández; Badillo, J. Flores; Murcia, J. A. Cobos

Electronic waste (e-waste), have a high potential as a source of precious metals, since they can contain metals like silver, gold, platinum, copper, zinc, nickel, tin and others. In this paper some e-waste were characterized using several analytical techniques as Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and inductively coupled plasma (ICP) in addition to the thermodynamic study by Pourbaix diagrams of silver (Ag), gold (Au), platinum (Pt), copper (Cu), nickel (Ni), tin (Sn) and zinc (Zn); considering an average low concentration of HNO3 (10% v/v). With results of the characterization was determined that the e-waste is an ideal source for the recovery of valuable metals. Similarly, the thermodynamic studies showed that it is possible to obtain all metallic species except Pt, in a potential window of 1.45V to 2.0V vs SCE.

Slags and ashes from municipal waste incineration in Poland - mineralogical and chemical composition

NASA Astrophysics Data System (ADS)

Kowalski, Piotr; Michalik, Marek

2013-04-01

In the next few years there will be a large change in the waste management system in Poland. Its primary aim will be reduction of the amount of landfilled waste by enhancing level of recycling, waste segregation, composting of biomass and incineration. The biggest investment during this transformation is construction of nine incinerators with assumed slags production around 200 thousand tons per year. Slag production is accompanied by fly ash generating. This ash can be a valuable raw material as fly ash from the power industry. Waste management system transformation will cause big increase in slag production in comparison to the present amount and will require taking necessary steps to ensure environmental safety. For this purpose, studies of slags and fly ashes in terms of environmental risk and potential impact on human health are significant. The object of the study are fly ashes and slags produced in the biggest municipal waste incineration power plant in Poland. Two series of samples obtained in municipal waste incineration process were studied in order to characterize mineralogical and chemical composition and to determine the concentrations of heavy metals and their possible negative environmental impact. Characteristics of these materials will be the basis for determining their value in application, for example in building industry. Mineralogical characteristic of slags was based on X-ray diffraction. Characteristic of structures and forms of occurrence of mineral phases was based on the optical microscopy and SEM imaging coupled with EDS analysis. Chemical analysis were performed using ICP-MS/ICP-AES methods. They allowed to follow variability between studied samples and gave basic information about metals. Metals in samples of slag and ashes are present as component of mineral phases and in the form of metallic inclusions in glass or minerals. Potentially hazardous concentrations for environment are observed for copper (330-4900ppm), zinc (1500-8100ppm) and lead (50-2400ppm). All samples are rich in amorphous phase. Municipal slags are rich in Si, Ca and Al, whereas Fe and Na are minor component. Fly ashes from incineration of waste are similar to Ca-type ashes from power industry. They are rich in Ca and Si and they contain minor amount of Al, K and Na. The main mineral components of municipal slags are quartz, gehlenite, calcite and lime. They are present in all samples. Smaller quantities of apatite, wollastonite, feldspar, anhydrite and magnetite were also detected. In addition to main components, two groups of associated minerals can be identified. The first group is represented by wollastonite and apatite, whereas in the second group magnetite and feldspar or anhydrite were detected. Moreover, if feldspar is present in the sample there is no anhydrite. Also the presence of magnetite is correlated with the absence of wollastonite and apatite. In all fly ash samples quartz, calcite, anhydrite, lime and halite or sylvite are present. Minor components are periclase, portlandite and syngenite, wollastonite and meionite. Here we can observe also some dependence. When halite and syngenite are present in sample there is no wollastonite and when gelenite is present, portlandite is absent.

Heavy metal content of combustible municipal solid waste in Denmark.

PubMed

Riber, Christian; Fredriksen, Gry S; Christensen, Thomas H

2005-04-01

Data on the heavy metal composition of outlets from Danish incinerators was used to estimate the concentration of Zn, Cu, Pb, Cr, Ni, Cd, As and Hg in combustible waste (wet as received) at 14 Danish incinerators, representing about 80% of the waste incinerated in Denmark. Zn (1020 mg kg(-1)), Cu (620 mg kg(-1)) and Pb (370 mg kg(-1)) showed the highest concentration, whereas Hg (0.6 mg kg(-1)) showed the lowest concentration. The variation among the incinerators was in most cases within a factor of two to three, except for Cr that in two cases showed unexplained high concentrations. The fact that the data represent many incinerators and, in several cases, observations from a period of 4 to 5 years provides a good statistical basis for evaluating the content of heavy metals in combustible Danish waste. Such data may be used for identifying incinerators receiving waste with high concentrations of heavy metals suggesting the introduction of source control, or, if repeated in time, the data must also be used for monitoring the impacts of national regulation controlling heavy metals. It is recommended that future investigations consider the use of sample digestion methods that ensure complete digestion in order to use the data for determining the total heavy metal content of waste.

Bio-extraction of precious metals from urban solid waste

NASA Astrophysics Data System (ADS)

Das, Subhabrata; Natarajan, Gayathri; Ting, Yen-Peng

2017-01-01

Reduced product lifecycle and increasing demand for electronic devices have resulted in the generation of huge volumes of electronic waste (e-waste). E-wastes contain high concentrations of toxic heavy metals, which have detrimental effects on health and the environment. However, e-wastes also contain significant concentrations of precious metals such as gold, silver and palladium, which can be a major driving force for recycling of urban waste. Cyanogenic bacteria such as Chromobacterium violaceum generate cyanide as a secondary metabolite which mobilizes gold into solution via a soluble gold-cyanide complex. However, compared to conventional technology for metal recovery, this approach is not effective, owing largely to the low concentration of lixiviants produced by the bacteria. To overcome the challenges of bioleaching of gold from e-waste, several strategies were adopted to enhance gold recovery rates. These included (i) pretreatment of e-waste to remove competing metal ions, (ii) mutation to adapt the bacteria to high pH environment, (iii) metabolic engineering to produce higher cyanide lixiviant, and (iv) spent medium leaching with adjusted initial pH. Compared to 7.1 % recovery by the wild type bacteria, these strategies achieved gold recoveries of 11.3%, 22.5%, 30% and 30% respectively at 0.5% w/v pulp density respectively. Bioleached gold was finally mineralized and precipitated as gold nanoparticles using the bacterium Delftia acidovorans. This study demonstrates the potential for enhancement of biocyanide production and gold recovery from electronic waste through different strategies, and extraction of solid gold from bioleached leachate.

Inhibition of acid mine drainage and immobilization of heavy metals from copper flotation tailings using a marble cutting waste

NASA Astrophysics Data System (ADS)

Tozsin, Gulsen

2016-01-01

Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide bearing wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings (sulfide- bearing wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the pH value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neutralizer. For comparison, CaCO3 was also used as a neutralizing agent. The average pH value of the leachate was 2.1 at the beginning of the experiment ( t = 0). In the experiment employing the marble cutting waste, the pH value of the leachate changed from 6.5 to 7.8, and the sulfate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings.

40 CFR Appendix V to Part 265 - Examples of Potentially Incompatible Waste

Code of Federal Regulations, 2013 CFR

2013-07-01

... Calcium Lithium Magnesium Potassium Sodium Zinc powder Other reactive metals and metal hydrides Potential... concentrated waste in Groups 1-A or 1-B Water Calcium Lithium Metal hydrides Potassium SO2Cl2, SOCl2, PCl3...

40 CFR Appendix V to Part 265 - Examples of Potentially Incompatible Waste

Code of Federal Regulations, 2012 CFR

2012-07-01

... Calcium Lithium Magnesium Potassium Sodium Zinc powder Other reactive metals and metal hydrides Potential... concentrated waste in Groups 1-A or 1-B Water Calcium Lithium Metal hydrides Potassium SO2Cl2, SOCl2, PCl3...

40 CFR Appendix V to Part 265 - Examples of Potentially Incompatible Waste

Code of Federal Regulations, 2014 CFR

2014-07-01

... Calcium Lithium Magnesium Potassium Sodium Zinc powder Other reactive metals and metal hydrides Potential... concentrated waste in Groups 1-A or 1-B Water Calcium Lithium Metal hydrides Potassium SO2Cl2, SOCl2, PCl3...

Leaching characteristics, ecotoxicity, and risk assessment based management of mine wastes

NASA Astrophysics Data System (ADS)

Kim, J.; Ju, W. J.; Jho, E. H.; Nam, K.; Hong, J. K.

2016-12-01

Mine wastes generated during mining activities in metal mines generally contain high concentrations of metals that may impose toxic effects to surrounding environment. Thus, it is necessary to properly assess the mining-impacted landscapes for management. The study investigated leaching characteristics, potential environmental effects, and human health risk of mine wastes from three different metal mines in South Korea (molybdenum mine, lead-zinc mine, and magnetite mine). The heavy metal concentrations in the leachates obtained by using the Korean Standard Test Method for Solid Wastes (STM), Toxicity Characteristics Leaching Procedure (TCLP), and Synthetic Precipitation Leaching Procedure (SPLP) met the Korea Waste Control Act and the USEPA region 3 regulatory levels accordingly, even though the mine wastes contained high concentrations of metals. Assuming that the leachates may get into nearby water sources, the leachate toxicity was tested using Daphnia Magna. The toxic unit (TU) values after 24 h and 48 h exposure of all the mine wastes tested met the Korea Allowable Effluent Water Quality Standards (TU<1). The column leaching test showed that the lead-zinc mine waste may have long-term toxic effects (TU>1 for the eluent at L/S of 30) implying that the long-term effect of mine wastes left in mining areas need to be assessed. Considering reuse of mine wastes as a way of managing mine wastes, the human health risk assessment of reusing the lead-zinc mine waste in industrial areas was carried out using the bioavailable fraction of the heavy metals contained in the mine wastes, which was determined by using the Solubility/Bioavailability Research Consortium method. There may be potential carcinogenic risk (9.7E-05) and non-carcinogenic risk (HI, Hazard Index of 1.0E+00) as CR≧1.0E-05 has carcinogenic risk and HI≧1.0E+00 has non-carcinogenic risk. Overall, this study shows that not only the concentration-based assessment but ecological toxic effect and human health risk based assessments can be utilized for mining-impacted landscapes management.

In Situ Quantification of [Re(CO)3]+ by Fluorescence Spectroscopy in Simulated Hanford Tank Waste.

PubMed

Branch, Shirmir D; French, Amanda D; Lines, Amanda M; Rapko, Brian M; Heineman, William R; Bryan, Samuel A

2018-02-06

A pretreatment protocol is presented that allows for the quantitative conversion and subsequent in situ spectroscopic analysis of [Re(CO) 3 ] + species in simulated Hanford tank waste. In this test case, the nonradioactive metal rhenium is substituted for technetium (Tc-99), a weak beta emitter, to demonstrate proof of concept for a method to measure a nonpertechnetate form of technetium in Hanford tank waste. The protocol encompasses adding a simulated waste sample containing the nonemissive [Re(CO) 3 ] + species to a developer solution that enables the rapid, quantitative conversion of the nonemissive species to a luminescent species which can then be detected spectroscopically. The [Re(CO) 3 ] + species concentration in an alkaline, simulated Hanford tank waste supernatant can be quantified by the standard addition method. In a test case, the [Re(CO) 3 ] + species was measured to be at a concentration of 38.9 μM, which was a difference of 2.01% from the actual concentration of 39.7 μM.

Treatment of Waste Lubricating Oil by Chemical and Adsorption Process Using Butanol and Kaolin

NASA Astrophysics Data System (ADS)

Riyanto; Ramadhan, B.; Wiyanti, D.

2018-04-01

Treatment of waste lubricating oil by chemical and adsorption process using butanol and kaolin has been done. Quality of lubricating oil after treatment was analysis using Atomic Absorption Spectrophotometer (AAS) and Gas Chromatography-Mass Spectrometry (GC-MS). The effects of the treatment of butanol, KOH, and kaolin to metals contain in waste lubricating oil treatment have been evaluated. Treatment of waste lubricating oil has been done using various kaolin weight, butanol, and KOH solution. The result of this research show metal content of Ca, Mg, Pb, Fe and Cr in waste lubricating oil before treatment are 1020.49, 367.02, 16.40, 36.76 and 1,80 ppm, respectively. The metal content of Ca, Mg, Pb, Fe and Cr in the waste lubricating oil after treatment are 0.17, 9.85, 34.07, 78.22 and 1.20 ppm, respectively. The optimum condition for treatment of waste lubricating oil using butanol, KOH, and kaolin is 30 mL, 3.0 g and 1.5 g, respectively. Chemical and adsorption method using butanol and kaolin can be used for decrease of metals contain in waste lubricating oil.

A long-term static immersion experiment on the leaching behavior of heavy metals from waste printed circuit boards.

PubMed

Zhao, Guo-Hua; Luo, Xing-Zhang; Chen, Gui; Zhao, Yong-Jun

2014-08-01

Printed circuit boards (PCBs) are the main components of electrical and electronic equipment (EEE). Waste PCBs contain several kinds of heavy metals, including Cu, Pb and Zn. We characterize the leaching of heavy metals (Cu, Pb, Zn and Ni) from waste PCBs in a pH range of 3.0 to 5.6 using a novel approach based on batch pH-static leaching experiments in this work. The results indicate that the leaching behavior of Cu, Pb, Zn and Ni is strongly dependent on pH. Leaching behavior also varies with different pH values and leaching times. The maximum concentrations of Cu, Pb, Zn and Ni in leachate from waste PCBs were 335.00, 17.57, 2.40 and 2.33 mg L(-1), respectively. The highest Pb, Ni, and Cu concentrations leached significantly exceeded the European Union waste-acceptance limit values with respect to inert waste landfills. The leaching of metals follows the shrinking core model with surface reaction control.

Urban Biomining: Biological Extraction of Metals and Materials from Electronics Waste Using a Synthetic Biology Approach

NASA Astrophysics Data System (ADS)

Urbina-Navarrete, J.; Rothschild, L.

2016-12-01

End-of-life electronics waste (e-waste) containing toxic and valuable materials is a rapidly progressing human health and environmental issue. Using synthetic biology tools, we have developed a recycling method for e-waste. Our innovation is to use a recombinant version of a naturally-occurring silica-degrading enzyme to depolymerize the silica in metal- and glass- containing e-waste components, and subsequently, to use engineered bacterial surfaces to bind and separate metals from a solution. The bacteria with bound metals can then be used as "bio-ink" to print new circuits using a novel plasma jet electronics printing technology. Here, we present the results from our initial studies that focus on the specificity of metal-binding motifs for a cognate metal. The candidate motifs that show high affinity and specificity will be engineered into bacterial surfaces for downstream applications in biologically-mediated metal recycling. Since the chemistry and role of Cu in metalloproteins is relatively well-characterized, we are using Cu as a proxy to elucidate metal and biological ligand interactions with various metals in e-waste. We assess the binding parameters of 3 representative classes of Cu-binding motifs using isothermal titration calorimetry; 1) natural motifs found in metalloproteins, 2) consensus motifs, and 3) rationally designed peptides that are predicted, in silico, to bind Cu. Our results indicate that naturally-occurring motifs have relative high affinity and specificity for Cu (association constant for Cu Ka 104 M-1, Zn Ka 103 M-1) when competing ions are present in the aqueous milieu. However, motifs developed through rational design by applying quantum mechanical methods that take into account complexation energies of the elemental binding partners and molecular geometry of the cognate metal, not only show high affinity for the cognate metal (Cu Ka 106 M-1), but they show specificity and discrimination against other metal ions that would be competitors for the same binding sites. This is an initial proof-of-concept study that focuses on Cu-binding; however the overall objective of this research is to have peptides that selectively bind many metals from e-waste and this would allow for the separation of the metals from a solution, at ambient temperatures and under non-toxic conditions.

Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge.

PubMed

Åmand, Lars-Erik; Kassman, Håkan

2013-08-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW(th) circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel. Copyright © 2013 Elsevier Ltd. All rights reserved.

Change of heavy metal speciation, mobility, bioavailability, and ecological risk during potassium ferrate treatment of waste-activated sludge.

PubMed

Yu, Ming; Zhang, Jian; Tian, Yu

2018-05-01

The effects of potassium ferrate treatment on the heavy metal concentrations, speciation, mobility, bioavailability, and environmental risk in waste-activated sludge (WAS) at various dosages of potassium ferrate and different treatment times were investigated. Results showed that the total concentrations of all metals (except Cd) were decreased slightly after treatment and the order of metal concentrations in WAS and treated waste-activated sludge (TWAS) was Mg > Zn > Cu > Cr > Pb > Ni > Cd. Most heavy metals in WAS remained in TWAS after potassium ferrate treatment with metal residual rates over 67.8% in TWAS. The distribution of metal speciation in WAS was affected by potassium ferrate treatment. The bioavailability and the mobility of heavy metals (except Mg) in TWAS were mitigated, compared to those in WAS. Meanwhile, the environmental risk of heavy metals (except Pb and Cu) was alleviated after potassium ferrate treatment.

Treatment of waste printed wire boards in electronic waste for safe disposal.

PubMed

Niu, Xiaojun; Li, Yadong

2007-07-16

The printed wire boards (PWBs) in electronic waste (E-waste) have been found to contain large amounts of toxic substances. Studies have concluded that the waste PWBs are hazardous wastes because they fails the toxicity characteristic leaching procedure (TCLP) test with high level of lead (Pb) leaching out. In this study, two treatment methods - high-pressure compaction and cement solidification - were explored for rendering the PWBs into non-hazardous forms so that they may be safely disposed or used. The high-pressure compaction method could turn the PWBs into high-density compacts with significant volume reduction, but the impact resistance of the compacts was too low to keep them intact in the environment for a long run. In contrast, the cement solidification could turn the PWBs into strong monoliths with high impact resistance and relatively high compressive strength. The leaching of the toxic heavy metal Pb from the solidified samples was evaluated by both a dynamic leaching test and the TCLP test. The dynamic leaching results revealed that Pb could be effectively confined in the solidified products under very harsh environmental conditions. The TCLP test results showed that the leaching level of Pb was far below the regulatory level of 5mg/L, suggesting that the solidified PWBs are no longer hazardous. It was concluded that the cement solidification is an effective way to render the waste PWBs into environmentally benign forms so that they can be disposed of as ordinary solid wastes or beneficially used in the place of concrete in some applications.

[Environmental toxicity of waste foundry sand].

PubMed

Zhang, Hai-Feng; Wang, Yu-Jue; Wang, Jin-Lin; Huang, Tian-You; Xiong, Ying

2013-03-01

The metal leaching characteristics and volatile organic compounds (VOCs) of five different types of waste foundry sands were analyzed with the toxicity characteristic leaching procedure (TCLP) and head space-gas chromatography (HS-GC). Microtox and soil dehydrogenase activity (DHA) tests were then used to evaluate the bio-effects of these waste sands. The results showed that due to the different metals poured and casting materials used to make the sand molds, there was significant difference among the five waste foundry sands in the compositions and concentrations of metal and organic pollutants. The concentrations of Fe in the leachates of iron and steel casting waste foundry sand exceeded the maximal allowable concentrations specified in the National Standard of Drinking Water Quality, whereas the As concentration in the leachate of aluminum casting waste foundry sand exceeded the standard. The five waste foundry sands had quite different compositions and levels of VOCs, which resulted in different levels of inhibition effects on the luminescent bacteria (30% and 95%). Additionally, the soil DHA tests suggested that metal pollutants in waste foundry sands may inhibit the soil microbial activity, whereas organics in the sands may slightly promote the microbial activity. The results of this study indicated that the waste foundry sands may pose considerable threat to the environment when improperly disposed.

LEACHING OF METALS FROM MINERAL PROCESSING WASTE

EPA Science Inventory

The purpose of this project is to test the leaching of Mineral processing Waste (MPW) contaminated with heavy metals using scientifically defendable leaching tests other than TCLP. Past experience and literature have shown that TCLP underestiates the levels of metals such as oxoa...

40 CFR 423.11 - Specialized definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... air conditioning wastes are not included. (c) The term chemical metal cleaning waste means any wastewater resulting from the cleaning of any metal process equipment with chemical compounds, including, but... from cleaning [with or without chemical cleaning compounds] any metal process equipment including, but...

40 CFR 423.11 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chemical metal cleaning waste means any wastewater resulting from the cleaning of any metal process equipment with chemical compounds, including, but not limited to, boiler tube cleaning. (d) The term metal cleaning waste means any wastewater resulting from cleaning [with or without chemical cleaning compounds...

40 CFR 423.11 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... chemical metal cleaning waste means any wastewater resulting from the cleaning of any metal process equipment with chemical compounds, including, but not limited to, boiler tube cleaning. (d) The term metal cleaning waste means any wastewater resulting from cleaning [with or without chemical cleaning compounds...

LEACHING OF METALS FROM MINERAL PROCESSING WASTE

EPA Science Inventory

The purpose of this project is to test the leaching of Mineral Processing Waste (MPW) contaminated with heavy metals using scientifically defendable leaching tests other than TCLP. Past experience and literature have shown that TCLP underestimates the levels of metals such as oxo...

Environmental applications of chitosan and its derivatives.

PubMed

Yong, Soon Kong; Shrivastava, Manoj; Srivastava, Prashant; Kunhikrishnan, Anitha; Bolan, Nanthi

2015-01-01

Chitosan originates from the seafood processing industry and is one of the most abundant of bio-waste materials. Chitosan is a by-product of the alkaline deacetylation process of chitin. Chemically, chitosan is a polysaccharide that is soluble in acidic solution and precipitates at higher pHs. It has great potential for certain environmental applications, such as remediation of organic and inorganic contaminants, including toxic metals and dyes in soil, sediment and water, and development of contaminant sensors. Traditionally, seafood waste has been the primary source of chitin. More recently, alternative sources have emerged such as fungal mycelium, mushroom and krill wastes, and these new sources of chitin and chitosan may overcome seasonal supply limitations that have existed. The production of chitosan from the above-mentioned waste streams not only reduces waste volume, but alleviates pressure on landfills to which the waste would otherwise go. Chitosan production involves four major steps, viz., deproteination, demineralization, bleaching and deacetylation. These four processes require excessive usage of strong alkali at different stages, and drives chitosan's production cost up, potentially making the application of high-grade chitosan for commercial remediation untenable. Alternate chitosan processing techniques, such as microbial or enzymatic processes, may become more cost-effective due to lower energy consumption and waste generation. Chitosan has proved to be versatile for so many environmental applications, because it possesses certain key functional groups, including - OH and -NH2 . However, the efficacy of chitosan is diminished at low pH because of its increased solubility and instability. These deficiencies can be overcome by modifying chitosan's structure via crosslinking. Such modification not only enhances the structural stability of chitosan under low pH conditions, but also improves its physicochemical characteristics, such as porosity, hydraulic conductivity, permeability, surface area and sorption capacity. Crosslinked chitosan is an excellent sorbent for trace metals especially because of the high flexibility of its structural stability. Sorption of trace metals by chitosan is selective and independent of the size and hardness of metal ions, or the physical form of chitosan (e.g., film, powder and solution). Both -OH and -NH2 groups in chitosan provide vital binding sites for complexing metal cations. At low pH, -NH3 + groups attract and coagulate negatively charged contaminants such as metal oxyanions, humic acids and dye molecules. Grafting certain functional molecules into the chitin structure improves sorption capacity and selectivity for remediating specific metal ions. For example, introducing sulfur and nitrogen donor ligands to chitosan alters the sorption preference for metals. Low molecular weight chitosan derivatives have been used to remediate metal contaminated soil and sediments. They have also been applied in permeable reactive barriers to remediate metals in soil and groundwater. Both chitosan and modified chitosan have been used to phytoremediate metals; however, the mechanisms by which they assist in mobilizing metals are not yet well understood. In addition, microbes have been used in combination with chitosan to remediate metals (e.g., Cu and Zn) in contaminated soils. Chitosan has also been used to remediate organic contaminants, such as oil-based wastewater, dyes, tannins, humic acids, phenols, bisphenoi-A, p-benzoquinone, organo-phosphorus insecticides, among others. Chitosan has also been utilized to develop optical and electrochemical sensors for in-situ detection of trace contaminants. In sensor technology, naturally-derived chitosan is used primarily as an immobilizing agent that results from its enzyme compatibility, and stabilizing effect on nanoparticles. Contaminant-sensing agents, such as enzymes, microbes and nanoparticles, have been homogeneously immobilized in chitosan gels by using coagulating (e.g., alginate, phosphate) or crosslinking agents (e.g., GA, ECH). Such immobilization maintains the stability of sensing elements in the chitosan gel phase, and prevents inactivation and loss of the sensing agent. In this review, we have shown that chitosan, an efficient by-product of a waste biomaterial, has great potential for many environmental applications. With certain limitations, chitosan and its derivatives can be used for remediating contaminated soil and wastewater. Notwithstanding, further research is needed to enhance the physicochemical properties of chitosan and mitigate its deficiencies.

The containment of toxic wastes: I. Long term metal movement in soils over a covered metalliferous waste heap at Parc lead-zinc mine, North Wales.

PubMed

Shu, J; Bradshaw, A D

1995-01-01

In order to stabilise and contain a toxic metalliferous waste heap at Parc Mine, North Wales, it was covered with 30-40 cm layer of quarry waste in 1977-1978, and sown with a grass/clover seed mixture. This study has examined subsequent metal movement in the cover material and its effect on vegetation. The results, especially when compared with previous observations, give no evidence of upward migration of metals by capillarity in the cover material. Sideways movement of leachate, however, appears to be carrying the metals into the cover material on the sloping sides, giving rise to increasing concentrations of heavy metals in the vegetation and dieback in some places. Root growth on the flat top of the heap is greater than on the slope, but the roots have not penetrated the waste and the contents of Pb, Zn and Cd in surface vegetation remain low. Surface covering of toxic waste with coarse materials restricting capillary rise is therefore a valid reclamation technique so long as lateral movement of toxic leachate can be controlled.

40 CFR 62.14103 - Emission limits for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2010 CFR

2010-07-01

... combustor metals, acid gases, organics, and nitrogen oxides. 62.14103 Section 62.14103 Protection of... combustor metals, acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals are specified in paragraphs (a)(1) through (a)(3) of this section. (1) The owner or...

Environmental assessment and management of metal-rich wastes generated in acid mine drainage passive remediation systems.

PubMed

Macías, Francisco; Caraballo, Manuel A; Nieto, José Miguel

2012-08-30

As acid mine drainage (AMD) remediation is increasingly faced by governments and mining industries worldwide, the generation of metal-rich solid residues from the treatments plants is concomitantly raising. A proper environmental management of these metal-rich wastes requires a detailed characterization of the metal mobility as well as an assessment of this new residues stability. The European standard leaching test EN 12457-2, the US EPA TCLP test and the BCR sequential extraction procedure were selected to address the environmental assessment of dispersed alkaline substrate (DAS) residues generated in AMD passive treatment systems. Significant discrepancies were observed in the hazardousness classification of the residues according to the TCLP or EN 12457-2 test. Furthermore, the absence of some important metals (like Fe or Al) in the regulatory limits employed in both leaching tests severely restricts their applicability for metal-rich wastes. The results obtained in the BCR sequential extraction suggest an important influence of the landfill environmental conditions on the metals released from the wastes. To ensure a complete stability of the pollutants in the studied DAS-wastes the contact with water or any other leaching solutions must be avoided and a dry environment needs to be provided in the landfill disposal selected. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of methods of preparation on distribution of heavy metals in different size fractions of municipal solid waste composts.

PubMed

Saha, J K; Panwar, N R; Coumar, M Vassanda

2013-11-01

The present study compares the distribution and nature of heavy metals in composts from 12 cities of India, prepared from different types of processed urban solid wastes, namely mixed wastes (MWC), partially segregated wastes (PSWC), and segregated bio-wastes (BWC). Compost samples were physically fractionated by wet sieving, followed by extraction of heavy metals by dilute HCl and NaOH. Bigger particles (>0.5 mm) constituted the major fraction in all three types of composts and had a relatively lower concentration of organic matter and heavy metals, the effect being more pronounced in MWC and PSWC in which a significant portion of the heavy metals was distributed in finer size fractions. Cd, Ni, Pb, and Zn were extracted to a greater extent by acid than by alkali, the difference being greater in MWC, which contained a higher amount of mineral matter. In contrast, Cu and Cr were extracted to a greater extent by dilute alkali, particularly from BWC containing a higher amount of organic matter. Water-soluble heavy metals were generally related to the water-soluble C or total C content as well as to pH, rather than to their total contents. This study concludes that wet sieving with dilute acid can effectively reduce heavy metal load in MWC and PSWC.

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... characteristic wastes from elemental phosphorus processing; radioactive wastes mixed with EPA Hazardous wastes... identified characteristic wastes from elemental phosphorus processing, radioactive waste mixed with D004-D011...

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... characteristic wastes from elemental phosphorus processing; radioactive wastes mixed with EPA Hazardous wastes... identified characteristic wastes from elemental phosphorus processing, radioactive waste mixed with D004-D011...

Functional magnetic microspheres

NASA Technical Reports Server (NTRS)

Rembaum, Alan (Inventor); Landel, Robert F. (Inventor); Yen, Shiao-Ping S. (Inventor)

1981-01-01

Functional magnetic particles are formed by dissolving a mucopolysaccharide such as chitosan in acidified aqueous solution containing a mixture of ferrous chloride and ferric chloride. As the pH of the solution is raised magnetite is formed in situ in the solution by raising the pH. The dissolved chitosan is a polyelectrolyte and forms micelles surrounding the granules at pH of 8-9. The chitosan precipitates on the granules to form microspheres containing the magnetic granules. On addition of the microspheres to waste aqueous streams containing dissolved ions, the hydroxyl and amine functionality of the chitosan forms chelates binding heavy metal cations such as lead, copper, and mercury and the chelates in turn bind anions such as nitrate, fluoride, phosphate and borate.

Children with health impairments by heavy metals in an e-waste recycling area.

PubMed

Zeng, Xiang; Xu, Xijin; Boezen, H Marike; Huo, Xia

2016-04-01

E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals derived from electronic waste (e-waste), such as, lead (Pb), cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), aluminum (Al) and cobalt (Co), differ in their chemical composition, reaction properties, distribution, metabolism, excretion and biological transmission. Our previous studies showed that heavy metal exposure have adverse effects on children's health including lower birth weight, lower anogenital distance, lower Apgar scores, lower current weight, lower lung function, lower hepatitis B surface antibody levels, higher prevalence of attention-deficit/hyperactivity disorder, and higher DNA and chromosome damage. Heavy metals influence a number of diverse systems and organs, resulting in both acute and chronic effects on children's health, ranging from minor upper respiratory irritation to chronic respiratory, cardiovascular, nervous, urinary and reproductive disease, as well as aggravation of pre-existing symptoms and disease. These effects of heavy metals on children's health are briefly discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biomining: metal recovery from ores with microorganisms.

PubMed

Schippers, Axel; Hedrich, Sabrina; Vasters, Jürgen; Drobe, Malte; Sand, Wolfgang; Willscher, Sabine

2014-01-01

Biomining is an increasingly applied biotechnological procedure for processing of ores in the mining industry (biohydrometallurgy). Nowadays the production of copper from low-grade ores is the most important industrial application and a significant part of world copper production already originates from heap or dump/stockpile bioleaching. Conceptual differences exist between the industrial processes of bioleaching and biooxidation. Bioleaching is a conversion of an insoluble valuable metal into a soluble form by means of microorganisms. In biooxidation, on the other hand, gold is predominantly unlocked from refractory ores in large-scale stirred-tank biooxidation arrangements for further processing steps. In addition to copper and gold production, biomining is also used to produce cobalt, nickel, zinc, and uranium. Up to now, biomining has merely been used as a procedure in the processing of sulfide ores and uranium ore, but laboratory and pilot procedures already exist for the processing of silicate and oxide ores (e.g., laterites), for leaching of processing residues or mine waste dumps (mine tailings), as well as for the extraction of metals from industrial residues and waste (recycling). This chapter estimates the world production of copper, gold, and other metals by means of biomining and chemical leaching (bio-/hydrometallurgy) compared with metal production by pyrometallurgical procedures, and describes new developments in biomining. In addition, an overview is given about metal sulfide oxidizing microorganisms, fundamentals of biomining including bioleaching mechanisms and interface processes, as well as anaerobic bioleaching and bioleaching with heterotrophic microorganisms.

Theoretic model and computer simulation of separating mixture metal particles from waste printed circuit board by electrostatic separator.

PubMed

Li, Jia; Xu, Zhenming; Zhou, Yaohe

2008-05-30

Traditionally, the mixture metals from waste printed circuit board (PCB) were sent to the smelt factory to refine pure copper. Some valuable metals (aluminum, zinc and tin) with low content in PCB were lost during smelt. A new method which used roll-type electrostatic separator (RES) to recovery low content metals in waste PCB was presented in this study. The theoretic model which was established from computing electric field and the analysis of forces on the particles was used to write a program by MATLAB language. The program was design to simulate the process of separating mixture metal particles. Electrical, material and mechanical factors were analyzed to optimize the operating parameters of separator. The experiment results of separating copper and aluminum particles by RES had a good agreement with computer simulation results. The model could be used to simulate separating other metal (tin, zinc, etc.) particles during the process of recycling waste PCBs by RES.

The use of sugar and alcohol industry waste in the adsorption of potentially toxic metals.

PubMed

Santos, Oseas Silva; Mendonça, André Gustavo Ribeiro; Santos, Josué Carinhanha Caldas; Silva, Amanda Paulina Bezerra; Costa, Silvanio Silverio Lopes; Oliveira, Luciana Camargo; Carmo, Janaina Braga; Botero, Wander Gustavo

2016-01-01

One of the waste products of the industrial process of the sugar and alcohol agribusiness is filter cake (FC). This waste product has high levels of organic matter, mainly proteins and lipids, and is rich in calcium, nitrogen, potassium and phosphorous. In this work we characterized samples of FC from sugar and alcohol industries located in sugarcane-producing regions in Brazil and assessed the adsorption of potentially toxic metals (Cu(II), Cd(II), Pb(II), Ni(II) and Cr(III)) by this waste in mono- and multi-elemental systems, seeking to use FC as an adsorbent in contaminated environments. The characterization of FCs showed significant differences between the samples and the adsorption studies showed retention of over 90% of potentially toxic metals. In a competitive environment (multi-metallic solution), the FC was effective in adsorbing all metals except lead, but less effective compared to the mono-metallic solution. These results show the potential for use of this residue as an adsorbent in contaminated environments.

Keratinase production and biodegradation of polluted secondary chicken feather wastes by a newly isolated multi heavy metal tolerant bacterium-Alcaligenes sp. AQ05-001.

PubMed

Yusuf, Ibrahim; Ahmad, Siti Aqlima; Phang, Lai Yee; Syed, Mohd Arif; Shamaan, Nor Aripin; Abdul Khalil, Khalilah; Dahalan, Farrah Aini; Shukor, Mohd Yunus

2016-12-01

Biodegradation of agricultural wastes, generated annually from poultry farms and slaughterhouses, can solve the pollution problem and at the same time yield valuable degradation products. But these wastes also constitute environmental nuisance, especially in Malaysia where their illegal disposal on heavy metal contaminated soils poses a serious biodegradation issue as feather tends to accumulate heavy metals from the surrounding environment. Further, continuous use of feather wastes as cheap biosorbent material for the removal of heavy metals from effluents has contributed to the rising amount of polluted feathers, which has necessitated the search for heavy metal-tolerant feather degrading strains. Isolation, characterization and application of a novel heavy metal-tolerant feather-degrading bacterium, identified by 16S RNA sequencing as Alcaligenes sp. AQ05-001 in degradation of heavy metal polluted recalcitrant agricultural wastes, have been reported. Physico-cultural conditions influencing its activities were studied using one-factor-at-a-time and a statistical optimisation approach. Complete degradation of 5 g/L feather was achieved with pH 8, 2% inoculum at 27 °C and incubation period of 36 h. The medium optimisation after the response surface methodology (RSM) resulted in a 10-fold increase in keratinase production (88.4 U/mL) over the initial 8.85 U/mL when supplemented with 0.5% (w/v) sucrose, 0.15% (w/v) ammonium bicarbonate, 0.3% (w/v) skim milk, and 0.01% (w/v) urea. Under optimum conditions, the bacterium was able to degrade heavy metal polluted feathers completely and produced valuable keratinase and protein-rich hydrolysates. About 83% of the feathers polluted with a mixture of highly toxic metals were degraded with high keratinase activities. The heavy metal tolerance ability of this bacterium can be harnessed not only in keratinase production but also in the bioremediation of heavy metal-polluted feather wastes. Copyright © 2016. Published by Elsevier Ltd.

EFFECT OF LIQUID TO SOLID RATIO ON LEACHING OF METALS FROM MINERAL PROCESSING WASTE

EPA Science Inventory

Various anthropogenic activities generate hazardous solid wastes that are affluent in heavy metals, which can cause significant damage to the environment an human health. A mineral processing waste was used to study the effect of liquid to solid ratio (L/S) on the leaching behav...

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

Lister, Tedd E; Parkman, Jacob A; Diaz Aldana, Luis A

A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anodemore » of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.« less

Chemical and biological extraction of metals present in E waste: A hybrid technology.

PubMed

Pant, Deepak; Joshi, Deepika; Upreti, Manoj K; Kotnala, Ravindra K

2012-05-01

Management of metal pollution associated with E-waste is widespread across the globe. Currently used techniques for the extraction of metals from E-waste by using either chemical or biological leaching have their own limitations. Chemical leaching is much rapid and efficient but has its own environmental consequences, even the future prospects of associated nanoremediation are also uncertain. Biological leaching on the other hand is comparatively a cost effective technique but at the same moment it is time consuming and the complete recovery of the metal, alone by biological leaching is not possible in most of the cases. The current review addresses the individual issues related to chemical and biological extraction techniques and proposes a hybrid-methodology which incorporates both, along with safer chemicals and compatible microbes for better and efficient extraction of metals from the E-waste. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of temperature on copper, iron and lead leaching from e-waste using citrate solutions.

PubMed

Torres, Robinson; Segura-Bailón, Brenda; Lapidus, Gretchen T

2018-01-01

E-waste is a potential source of large quantities of metals. The ability of citrate solutions to recover base metals from these materials has been demonstrated. In the present study, the effect of the temperature on base metal leaching capacity by the citrate solutions is determined. The material employed consisted of a mechanically prepared, gravity concentrated e-waste, with a metallic content greater than 90%. The leaching conditions were selected based on previous research performed by the authors (0.5 M sodium citrate, pH 4.5 and 20 g per liter e-waste concentrate). Leaching tests were performed at temperatures between 0° and 70 °C. The initial leaching rates for the three metals increased with temperature. However, these tapered off with time for temperatures above 30 °C, which can be associated to citrate destruction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II).

PubMed

Agarwal, Rashmi A

2018-03-09

A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr 2 O 3 /CrO 2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

Acquisition of Co metal from spent lithium-ion battery using emulsion liquid membrane technology and emulsion stability test

NASA Astrophysics Data System (ADS)

Yuliusman; Wulandari, P. T.; Amiliana, R. A.; Huda, M.; Kusumadewi, F. A.

2018-03-01

Lithium-ion batteries are the most common type to be used as energy source in mobile phone. The amount of lithium-ion battery wastes is approximated by 200 – 500 ton/year. In one lithium-ion battery, there are 5 – 20% of cobalt metal, depend on the manufacturer. One of the way to recover a valuable metal from waste is leaching process then continued with extraction, which is the aim of this study. Spent lithium-ion batteries will be characterized with EDX and AAS, the result will show the amount of cobalt metal with form of LiCoO2 in the cathode. Hydrochloric acid concentration used is 4 M, temperature 80°C, and reaction time 1 hour. This study will discuss the emulsion stability test on emulsion liquid membrane. The purpose of emulsion stability test in this study was to determine optimum concentration of surfactant and extractant to produce a stable emulsion. Surfactant and extractant used were SPAN 80 and Cyanex 272 respectively with both concentrations varied. Membrane and feed phase ratios used in this experiment was 1 : 2. The optimum results of this study were SPAN 80 concentrations of 10% w/v and Cyanex 272 0.7 M.

Synthesis of non-toxic As and Cr nanoparticles through redox activity of highly flexible layered coordination polymer of Ni(II)

NASA Astrophysics Data System (ADS)

Agarwal, Rashmi A.

2018-03-01

A simple method for the sequestration of As(III) and Cr(VI) from water has been demonstrated by utilizing a highly flexible porous coordination polymer (PCP) of Ni(II) in its as synthesized form or without solvent removal. This PCP reduces the high toxicity of As(III) and Cr(VI) ions into non-toxic As(0) and Cr/Cr2O3/CrO2 (zero, tri and tetravalent) nanoparticles (NPs) within its pores, and this is characterized by powder x-ray diffraction, x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. The high functionality of this polymer is due to the presence of monodentate carboxylate groups of a benzenetricarboxylate linker, which provide anchoring sites to the metal ions of the metal precursors. Due to the highly oxidising nature of these toxic ions, a redox reaction takes place between the framework metal ions and toxic metal ions, which is explained by an electron paramagnetic resonance study. This is the first report to synthesize non-toxic, as well as useful, NPs of As and Cr from their highly toxic ions within the cavities of a PCP for remediation of the toxic waste stream and contaminated waste water.

Removal of heavy metals from waste streams

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

Spence, M.D.; Kozaruk, J.M.; Melvin, M.

1988-07-19

A method for removing heavy metals from effluent water is described comprising performing sequentially the following steps: (a) adding from 7-333 ppm of an anionic surfactant to the effluent water to provide coagulatable heavy metal ion; (b) adjusting the effluent water pH to within the range of 8 to 10, (c) providing from 10-200 ppm of a cationic coagulant to coagulate the heavy metal ion, (d) providing from 0.3 to 5.0 ppm of a polymeric flocculant whereby a heavy metal containing floc is formed for removal from the effluent water, and, (e) then removing the floc from the effluent water,more » wherein the anionic surfactant is sodium lauryl ether sulfate. The cationic coagulant is selected from the group consisting of diallyl dimethylammonium chloride polymer, epichlorohydrin dimethylamine polymer, ethylene amine polymer, polyaluminum chloride, and alum; and the flocculant is an acrylamide/sodium acrylate copolymer having an RSV greater than 23.« less

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water.

PubMed

Ellison, Michael B; de Nys, Rocky; Paul, Nicholas A; Roberts, David A

2014-01-01

The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn) and metalloids (As and Se) in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in "clean" water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn) more rapidly than metalloids (As, Mo and Se). Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

Waste Isolation Pilot Plant Materials Interface Interactions Test: Papers presented at the Commission of European Communities workshop on in situ testing of radioactive waste forms and engineered barriers

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

Molecke, M.A.; Sorensen, N.R.; Wicks, G.G.

The three papers in this report were presented at the second international workshop to feature the Waste Isolation Pilot Plant (WIPP) Materials Interface Interactions Test (MIIT). This Workshop on In Situ Tests on Radioactive Waste Forms and Engineered Barriers was held in Corsendonk, Belgium, on October 13--16, 1992, and was sponsored by the Commission of the European Communities (CEC). The Studiecentrum voor Kernenergie/Centre D`Energie Nucleaire (SCK/CEN, Belgium), and the US Department of Energy (via Savannah River) also cosponsored this workshop. Workshop participants from Belgium, France, Germany, Sweden, and the United States gathered to discuss the status, results and overviews ofmore » the MIIT program. Nine of the twenty-five total workshop papers were presented on the status and results from the WIPP MIIT program after the five-year in situ conclusion of the program. The total number of published MIIT papers is now up to almost forty. Posttest laboratory analyses are still in progress at multiple participating laboratories. The first MIIT paper in this document, by Wicks and Molecke, provides an overview of the entire test program and focuses on the waste form samples. The second paper, by Molecke and Wicks, concentrates on technical details and repository relevant observations on the in situ conduct, sampling, and termination operations of the MIIT. The third paper, by Sorensen and Molecke, presents and summarizes the available laboratory, posttest corrosion data and results for all of the candidate waste container or overpack metal specimens included in the MIIT program.« less

Three-Loop Automatic of Control System the Landfill of Household Solid Waste

NASA Astrophysics Data System (ADS)

Sereda, T. G.; Kostarev, S. N.

2017-05-01

The analysis of models of governance ground municipal solid waste (MSW). Considered a distributed circuit (spatio-temporal) ground control model. Developed a dynamic model of multicontour control landfill. Adjustable parameters are defined (the ratio of CH4 CO2 emission/fluxes, concentrations of heavy metals ions) and control (purging array, irrigation, adding reagents). Based on laboratory studies carried out with the analysis of equity flows and procedures developed by the transferring matrix that takes into account the relationship control loops. A system of differential equations in the frequency and time domains. Given the numerical approaches solving systems of differential equations in finite differential form.

Incineration and pyrolysis vs. steam gasification of electronic waste.

PubMed

Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

2018-05-15

Constructional complexity of items and their integration are the most distinctive features of electronic wastes. These wastes consist of mineral and polymeric materials and have high content of valuable metals that could be recovered. Elimination of polymeric components (especially epoxy resins) while leaving non-volatile mineral and metallic phases is the purpose of thermal treatment of electronic wastes. In the case of gasification, gaseous product of the process may be, after cleaning, used for energy recovery or chemical synthesis. If not melted, metals from solid products of thermal treatment of electronic waste could be recovered by hydrometallurgical processing. Three basic, high temperature ways of electronic waste processing, i.e. smelting/incineration, pyrolysis and steam gasification were shortly discussed in the paper, giving a special attention to gasification under steam, illustrated by laboratory experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

Metals removal and recovery in bioelectrochemical systems: A review.

PubMed

Nancharaiah, Y V; Venkata Mohan, S; Lens, P N L

2015-11-01

Metal laden wastes and contamination pose a threat to ecosystem well being and human health. Metal containing waste streams are also a valuable resource for recovery of precious and scarce elements. Although biological methods are inexpensive and effective for treating metal wastewaters and in situ bioremediation of metal(loid) contamination, little progress has been made towards metal(loid) recovery. Bioelectrochemical systems are emerging as a new technology platform for removal and recovery of metal ions from metallurgical wastes, process streams and wastewaters. Biodegradation of organic matter by electroactive biofilms at the anode has been successfully coupled to cathodic reduction of metal ions. Until now, leaching of Co(II) from LiCoO2 particles, and removal of metal ions i.e. Co(III/II), Cr(VI), Cu(II), Hg(II), Ag(I), Se(IV), and Cd(II) from aqueous solutions has been demonstrated. This article reviews the state of art research of bioelectrochemical systems for removal and recovery of metal(loid) ions and pertaining removal mechanisms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Potential resource and toxicity impacts from metals in waste electronic devices.

PubMed

Woo, Seung H; Lee, Dae Sung; Lim, Seong-Rin

2016-04-01

As a result of the continuous release of new electronic devices, existing electronic devices are quickly made obsolete and rapidly become electronic waste (e-waste). Because e-waste contains a variety of metals, information about those metals with the potential for substantial environmental impact should be provided to manufacturers, recyclers, and disposers to proactively reduce this impact. This study assesses the resource and toxicity (i.e., cancer, noncancer, and ecotoxicity) potentials of various heavy metals commonly found in e-waste from laptop computers, liquid-crystal display (LCD) monitors, LCD TVs, plasma TVs, color cathode ray tube (CRT) TVs, and cell phones and then evaluates such potentials using life cycle impact-based methods. Resource potentials derive primarily from Cu, Sb, Ag, and Pb. Toxicity potentials derive primarily from Pb, Ni, and Hg for cancer toxicity; from Pb, Hg, Zn, and As for noncancer toxicity; and from Cu, Pb, Hg, and Zn for ecotoxicity. Therefore, managing these heavy metals should be a high priority in the design, recycling, and disposal stages of electronic devices. © 2015 SETAC.

Benchmarking Anthropogenic Heavy Metals Emissions: Australian and Global Urban Environmental Health Risk Based Indicators of Sustainability

ERIC Educational Resources Information Center

Dejkovski, Nick

2016-01-01

In Australia, the impacts of urbanisation and human activity are evident in increased waste generation and the emissions of metals into the air, land or water. Metals that have accumulated in urban soils almost exclusively anthropogenically can persist for long periods in the environment. Anthropogenic waste emissions containing heavy metals are a…

Characterization of Printed Circuit Boards for Metal and Energy Recovery after Milling and Mechanical Separation

PubMed Central

Bizzo, Waldir A.; Figueiredo, Renata A.; de Andrade, Valdelis F.

2014-01-01

The proper disposal of electrical and electronic waste is currently a concern of researchers and environmental managers not only because of the large volume of such waste generated, but also because of the heavy metals and toxic substances it contains. This study analyzed printed circuit boards (PCBs) from discarded computers to determine their metal content and characterized them as solid waste and fuel. The analysis showed that PCBs consist of approximately 26% metal, made up mainly of copper, lead, aluminum, iron and tin, as well as other heavy metals such as cadmium and nickel. Comparison with the results of other studies indicated that the concentration of precious metals (gold and silver) has declined over time. Analysis of the leachate revealed high concentrations of cadmium and lead, giving the residue the characteristics of hazardous waste. After milling the PCBs, we found that larger amounts of metal were concentrated in smaller fractions, while the lightest fraction, obtained by density separation, had a gross calorific value of approximately 11 MJ/kg, although with a high ash content. Milling followed by density separation proved potentially useful for recovery of metals and energy-rich fractions. PMID:28788692

[Determination of metals in waste bag filter of steel works by microwave digestion-flame atomic absorption spectrometry].

PubMed

Ning, Xun-An; Zhou, Yun; Liu, Jing-Yong; Wang, Jiang-Hui; Li, Lei; Ma, Xiao-Guo

2011-09-01

A method of microwave digestion technique-flame atomic absorption spectrometry was proposed to determine the total contents of Cu, Zn, Pb, Cd, Cr and Ni in five different kinds of waste bag filters from a steel plant. The digestion effects of the six acid systems on the heavy metals digestion were studied for the first time. The relative standard deviation (RSD) of the method was between 1.02% and 9.35%, and the recovery rates obtained by standard addition method ranged from 87.7% to 105.6%. The results indicated that the proposed method exhibited the advantages of simplicity, speediness, accuracy and repeatability, and it was suitable for determining the metal elements of the waste bag filter. The results also showed that different digestion systems should be used according to different waste bag filters. The waste bag filter samples from different production processes had different metal elements content. The Pb and Zn were the highest in the waste bag filters, while the Cu, Ni, Cd and Cr were relatively lower. These determination results provided the scientific data for further treatment and disposal of the waste bag filter.

Waste printed circuit board recycling techniques and product utilization.

PubMed

Hadi, Pejman; Xu, Meng; Lin, Carol S K; Hui, Chi-Wai; McKay, Gordon

2015-01-01

E-waste, in particular waste PCBs, represents a rapidly growing disposal problem worldwide. The vast diversity of highly toxic materials for landfill disposal and the potential of heavy metal vapors and brominated dioxin emissions in the case of incineration render these two waste management technologies inappropriate. Also, the shipment of these toxic wastes to certain areas of the world for eco-unfriendly "recycling" has recently generated a major public outcry. Consequently, waste PCB recycling should be adopted by the environmental communities as an ultimate goal. This article reviews the recent trends and developments in PCB waste recycling techniques, including both physical and chemical recycling. It is concluded that the physical recycling techniques, which efficiently separate the metallic and nonmetallic fractions of waste PCBs, offer the most promising gateways for the environmentally-benign recycling of this waste. Moreover, although the reclaimed metallic fraction has gained more attention due to its high value, the application of the nonmetallic fraction has been neglected in most cases. Hence, several proposed applications of this fraction have been comprehensively examined. Copyright © 2014 Elsevier B.V. All rights reserved.

Safety Checklist

DTIC Science & Technology

1994-05-01

given prior to issuing or renewing an OF 346? 13. Are operators’ DA Forms 348 reviewed annually for— a. Safety awards? b. Expiration of permits...2. Family safety. Are soldiers instructed to— _ a. Rid basements, closets, and attics of old rugs, papers, mattresses, broken furniture , and...place oily polishing rags or waste in covered metal cans? d. Store paint in tightly closed containers? e. Warn family members to never use gasoline

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

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

Asmussen, Robert M.; Lawter, Amanda R.; Stephenson, John R.

Washington River Protection Solutions (WRPS) is collecting relevant available data on waste forms for use as a supplemental immobilization technology, to provide the additional capacity needed to treat low-activity waste (LAW) in Hanford Site tanks and complete the tank waste cleanup mission in a timely and cost-effective manner. One candidate supplemental waste form, fabricated using a low-temperature process, is a cementitious grout called Cast Stone. Cast Stone has been under investigation for this application at Pacific Northwest National Laboratory (PNNL) since initial screening tests in FY13. This report is the culmination of work to lower the diffusivities of Tc andmore » I from Cast Stone using getters. Getters are compounds added to a system designed to selectively sequester a species of interest to provide increased stability to the species. The work contained within this report is related to waste form development and testing, and does not directly support the 2017 integrated disposal facility (IDF) performance assessment. However, this work contains valuable information which may be used in performance assessment maintenance past FY17, and in future waste form development. This report on performance characterization of Tc and I getters in Cast Stone fabricated with simulated LAW covers several areas of interest and major findings to WRPS: investigating performance of potassium metal sulfide (KMS-2-SS) and tin (II) apatite (Sn-A) as Tc getters when incorporated into Cast Stone; investigating performance of silver exchanged zeolite (Ag-Z) and argentite (Arg) as I getters when incorporated into Cast Stone; utilizing sequential addition of Tc and I getters to overcome any deleterious interactions between the getters in solution; determining, for the first time, Tc distribution within the cured Cast Stone and its evolution during leaching; and performing solid state characterization of getters and Cast Stone samples to support leach test findings and develop a mechanistic understanding of the processes that control Tc and I release into solution.« less

Economic evaluation of an electrochemical process for the recovery of metals from electronic waste.

PubMed

Diaz, Luis A; Lister, Tedd E

2018-04-01

As the market of electronic devices continues to evolve, the waste stream generated from antiquated technology is increasingly view as an alternative to substitute primary sources of critical a value metals. Nevertheless, the sustainable recovery of materials can only be achieved by environmentally friendly processes that are economically competitive with the extraction from mineral ores. Hence, This paper presents the techno-economic assessment for a comprehensive process for the recovery of metals and critical materials from e-waste, which is based in an electrochemical recovery (ER) technology. Economic comparison is performed with the treatment of e-waste via smelting, which is currently the primary route for recycling metals from electronics. Results indicate that the electrochemical recovery process is a competitive alternative for the recovery of value from electronic waste when compared with the traditional black Cu smelting process. A significantly lower capital investment, 2.9 kg e-waste per dollar of capital investment, can be achieved with the ER process vs. 1.3 kg per dollar in the black Cu smelting process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Waste separation: Does it influence municipal waste combustor emissions?

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

Chandler, A.J.; Rigo, H.G.

1996-09-01

It has been suggested that MSW incinerator emissions show significant variations because of the heterogeneous nature of the waste fed to the furnace. This argument has even been used to propose banning certain materials from incinerators. However, data previously reported by the authors suggests that a large portion of the trace metals come from natural sources. Furthermore, full scale incinerator spiking experiments suggest that certain forms of trace metals have minimal effects on stack emissions. Similar studies with chlorinated plastics have failed to identify a significant effect on incinerator dioxin emissions. The implication of segregating the lawn and garden wastemore » and other fines from the furnace feed is explored using data from a 400 tpd mass burn facility equipped with a conditioning tower, dry reactor and fabric filter air pollution control system (APCS) preceded by an NRT separation system. The stack emissions have been tested periodically since commissioning to characterize emissions for various seasons using both processed fuel and raw MSW. Front end processing to remove selected portions of the waste stream based upon size or physical properties, i.e. fines, grass, or ferrous materials, did not result in a statistically significant difference in stack emissions. System operating regime, and in particular those that effect the effective air to cloth ratio in the fabric filter, appear to be the principal influence on emission levels.« less

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.

Selective extraction and recovery of rare earth metals from phosphor powders in waste fluorescent lamps using an ionic liquid system.

PubMed

Yang, Fan; Kubota, Fukiko; Baba, Yuzo; Kamiya, Noriho; Goto, Masahiro

2013-06-15

The recycling of rare earth metals from phosphor powders in waste fluorescent lamps by solvent extraction using ionic liquids was studied. Acid leaching of rare earth metals from the waste phosphor powder was examined first. Yttrium (Y) and europium (Eu) dissolved readily in the acid solution; however, the leaching of other rare earth metals required substantial energy input. Ionization of target rare earth metals from the waste phosphor powders into the leach solution was critical for their successful recovery. As a high temperature was required for the complete leaching of all rare earth metals, ionic liquids, for which vapor pressure is negligible, were used as an alternative extracting phase to the conventional organic diluent. An extractant, N, N-dioctyldiglycol amic acid (DODGAA), which was recently developed, showed a high affinity for rare earth metal ions in liquid-liquid extraction although a conventional commercial phosphonic extractant did not. An effective recovery of the rare earth metals, Y, Eu, La and Ce, from the metal impurities, Fe, Al and Zn, was achieved from the acidic leach solution of phosphor powders using an ionic liquid containing DODGAA as novel extractant system. Copyright © 2013 Elsevier B.V. All rights reserved.

Systematic characterization of generation and management of e-waste in China.

PubMed

Duan, Huabo; Hu, Jiukun; Tan, Quanyin; Liu, Lili; Wang, Yanjie; Li, Jinhui

2016-01-01

Over the last decade, there has been much effort to promote the management of e-waste in China. Policies have been affected to prohibit imports and to control pollution. Research has been conducted in laboratories and on large-scale industrial operations. A subsidy system to support sound e-waste recycling has been put in place. However, the handling of e-waste is still a concern in China and the issue remains unresolved. There has been relatively little work to follow up this issue or to interpret continuing problems from the perspective of sustainable development. This paper first provides a brief overview of conventional and emerging environmental pollution in Chinese "famous" e-waste dismantling areas, including Guiyu in Guangdong and Wenling in Zhejiang. Environmentalists have repeatedly proven that these areas are significantly polluted. Importing and backyard recycling are decreasing but are ongoing. Most importantly, no work is being done to treat or remediate the contaminated environmental media. The situation is exacerbated by the rising tide of e-waste generated by domestic update of various electronics. This study, therefore, employs a Sales Obsolescence Model approach to predict the generation of e-waste. When accounting for weight, approximately 8 million tons of e-waste will be generated domestically in 2015, of which around 50% is ferrous metals, followed by miscellaneous plastic (30%), copper metal and cables (8%), aluminum (5%), and others (7%). Of this, 3.6% will come from scrap PCBs and 0.2% from lead CRT glass. While more and more end-of-life electronics have been collected and treated by formal or licensed recyclers in China in terms of our analysis, many of them only have dismantling and separation activities. Hazardous e-wastes, including those from PCBs, CRT glass, and brominated flame retardant (BFR) plastics, have become problematic and probably flow to small or backyard recyclers without environmentally sound management. Traditional technologies are still being used to recover precious metals--such as cyanide method of gold hydrometallurgy--from e-waste. While recovery rates of precious metals from e-waste are above 50%, it has encountered some challenges from environmental considerations. Worse, many critical metals contained in e-waste are lost because the recovery rates are less than 1%. On the other hand, this implies that there is opportunity to develop the urban mine of the critical metals from e-waste.

Development of Technosols in abandoned mine lands to reduce hazards to ecosystems and human health

NASA Astrophysics Data System (ADS)

Zornoza, Raúl; Martínez-Martínez, Silvia; Acosta, Jose A.; Ángeles Muñoz, M.; Gómez-Garrido, Melisa; Gabarrón, Maria; Gómez-López, Maria Dolores; Faz, Ángel

2017-04-01

Mine tailings and residues dumped into the environment owing to mine ore processing activities have numerous restrictions affecting their development into natural soils, such as strong acidity, high concentrations and mobility of metals and metalloids, high salinity and extremely low organic matter content, which hinders the development of vegetation. This leads to the presence of bare surfaces which act as sources of water pollution and metal containing dusts, affecting natural ecosystems and populated areas in the surroundings. Therefore, there is a need to develop strategies to reduce the impact of tailings and mine residues spread on mine landscapes to reduce environmental and public health hazards and guarantee true land reclamation. One effective remediation option is the creation of Technosols by use of different materials, wastes and amendments derived from anthropogenic activities. For this purpose, the proper selection of materials is critical to convert metals to forms less soluble, mobile and toxic, so microorganisms, vegetation and animals can grow, and erosion rates are minimized so that metals do not reach populated areas. This goal can be achieved by applying materials with metal stabilization potential, to transform bioavailable metal species into geochemically stable forms. For this purpose, we have created Technosols in different mine tailings ponds located in SE Spain by use of different materials such as pig manure, pig slurry and marble waste. After 6 months of Technosol creation in field, seedlings from different native plant species were manually introduced for afforestation of the area. To monitor the evolution of soil quality and vegetation cover, four plots (10 m x 10 m) were established in each tailings pond, which were monitored every 6 months for 3 years. Results indicated that the created Technosol was efficient at significantly decreasing metal mobility by 90-99% depending on the metal. In addition, soil quality, fertility and structure increased, associated to increased microbial biomass and activity and development of vegetation. Vegetation cover at the end of the study was 65% of the total surface, with appearance of second generation individuals, suggesting the self-sustainability of the new ecosystem. Owing to the creation of a soil, metals are immobilized and soil particles are retained by increased soil aggregate stability and vegetation cover; so, the dispersion of metals to the surroundings by erosion and leaching is minimized, decreasing the hazards for human health and the environment.

Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

PubMed Central

Adama, M.; Esena, R.; Fosu-Mensah, B.; Yirenya-Tawiah, D.

2016-01-01

Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites. PMID:27034685

Impeding 99Tc(IV) mobility in novel waste forms

DOE PAGES

Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; ...

2016-06-30

Technetium ( 99Tc) is a long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state1. Immobilization of Tc in mineral substrates is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels2, 3 has been proposed as a novel method to increase Tc retention in glass waste forms. However, experiments with Tc-magnetite under high temperature and oxic conditions showed re-oxidation of Tc(IV) to volatile pertechnetate Tc(VII)O4-.4, 5 Here we address this problem with large-scale ab initio molecular dynamics simulations and propose that elevated temperatures, 1st row transition metal dopants can significantly enhancemore » Tc retention in the order Co > Zn > Ni. Experiments with doped spinels at T=700 ºC provided quantitative confirmation of increased Tc retention in the same order predicted by theory. This work highlights the power of modern state-of-the-art simulations to provide essential insights and generate bottom-up design criteria of complex oxide materials at elevated temperatures.« less

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... include, but is not limited to, elements such as segregation and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation...

40 CFR 60.55c - Waste management plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... include, but is not limited to, elements such as segregation and recycling of paper, cardboard, plastics, glass, batteries, food waste, and metals (e.g., aluminum cans, metals-containing devices); segregation...

Biosolid colloid-mediated transport of copper, zinc, and lead in waste-amended soils.

PubMed

Karathanasis, A D; Johnson, D M C; Matocha, C J

2005-01-01

Increasing land applications of biosolid wastes as soil amendments have raised concerns about potential toxic effects of associated metals on the environment. This study investigated the ability of biosolid colloids to transport metals associated with organic waste amendments through subsurface soil environments with leaching experiments involving undisturbed soil monoliths. Biosolid colloids were fractionated from a lime-stabilized, an aerobically digested, and a poultry manure organic waste and applied onto the monoliths at a rate of 0.7 cm/h. Eluents were monitored for Cu, Zn, Pb, and colloid concentrations over 16 to 24 pore volumes of leaching. Mass-balance calculations indicated significantly higher (up to 77 times) metal elutions in association with the biosolid colloids in both total and soluble fractions over the control treatments. Eluted metal loads varied with metal, colloid, and soil type, following the sequences Zn = Cu > Pb, and ADB > PMB > LSB colloids. Colloid and metal elution was enhanced by decreasing pH and colloid size, and increasing soil macroporosity and organic matter content. Breakthrough curves were mostly irregular, showing several maxima and minima as a result of preferential macropore flow and multiple clogging and flushing cycles. Soil- and colloid-metal sorption affinities were not reliable predictors of metal attenuation/elution loads, underscoring the dynamic nature of transport processes. The findings demonstrate the important role of biosolid colloids as contaminant carriers and the significant risk they pose, if unaccounted, for soil and ground water contamination in areas receiving heavy applications of biosolid waste amendments.

A critical review of the bioavailability and impacts of heavy metals in municipal solid waste composts compared to sewage sludge.

PubMed

Smith, Stephen R

2009-01-01

The content, behaviour and significance of heavy metals in composted waste materials is important from two potentially conflicting aspects of environmental legislation in terms of: (a) defining end-of-waste criteria and increasing recycling of composted residuals on land and (b) protecting soil quality by preventing contamination. This review examines the effects of heavy metals in compost and amended soil as a basis for achieving a practical and sustainable balance between these different policy objectives, with particular emphasis on agricultural application. All types of municipal solid waste (MSW) compost contain more heavy metals than the background concentrations present in soil and will increase their contents in amended soil. Total concentrations of heavy metals in source-segregated and greenwaste compost are typically below UK PAS100 limits and mechanical segregated material can also comply with the metal limits in UK PAS100, although this is likely to be more challenging. Zinc and Pb are numerically the elements present in the largest amounts in MSW-compost. Lead is the most limiting element to use of mechanically-segregated compost in domestic gardens, but concentrations are typically below risk-based thresholds that protect human health. Composted residuals derived from MSW and greenwaste have a high affinity for binding heavy metals. There is general consensus in the scientific literature that aerobic composting processes increase the complexation of heavy metals in organic waste residuals, and that metals are strongly bound to the compost matrix and organic matter, limiting their solubility and potential bioavailability in soil. Lead is the most strongly bound element and Ni the weakest, with Zn, Cu and Cd showing intermediate sorption characteristics. The strong metal sorption properties of compost produced from MSW or sewage sludge have important benefits for the remediation of metal contaminated industrial and urban soils. Compost and sewage sludge additions to agricultural and other soils, with background concentrations of heavy metals, raise the soil content and the availability of heavy metals for transfer into crop plants. The availability in soil depends on the nature of the chemical association between a metal with the organic residual and soil matrix, the pH value of the soil, the concentration of the element in the compost and the soil, and the ability of the plant to regulate the uptake of a particular element. There is no evidence of increased metal release into available forms as organic matter degrades in soil once compost applications have ceased. However, there is good experimental evidence demonstrating the reduced bioavailability and crop uptake of metals from composted biosolids compared to other types of sewage sludge. It may therefore be inferred that composting processes overall are likely to contribute to lowering the availability of metals in amended soil compared to other waste biostabilisation techniques. The total metal concentration in compost is important in controlling crop uptake of labile elements, like Zn and Cu, which increases with increasing total content of these elements in compost. Therefore, low metal materials, which include source-segregated and greenwaste composts, are likely to have inherently lower metal availabilities overall, at equivalent metal loading rates to soil, compared to composted residuals with larger metal contents. This is explained because the compost matrix modulates metal availability and materials low in metals have stronger sorption capacity compared to high metal composts. Zinc is the element in sewage sludge-treated agricultural soil identified as the main concern in relation to potential impacts on soil microbial activity and is also the most significant metal in compost with regard to soil fertility and microbial processes. However, with the exception of one study, there is no other tangible evidence demonstrating negative impacts of heavy metals applied to soil in compost on soil microbial processes and only positive effects of compost application on the microbial status and fertility of soil are reported. The negative impacts on soil microorganisms apparent in one long-term field experiment could be explained by the exceptionally high concentrations of Cd and other elements in the applied compost, and of Cd in the compost-amended soil, which are unrepresentative of current practice and compost quality. The metal contents of source-segregated MSW or greenwaste compost are smaller compared to mechanically-sorted MSW-compost and sewage sludge, and low metal materials also have the smallest potential metal availabilities. Composting processes also inherently reduce metal availability compared to other organic waste stabilisation methods. Therefore, risks to the environment, human health, crop quality and yield, and soil fertility, from heavy metals in source-segregated MSW or greenwaste-compost are minimal. Furthermore, composts produced from mechanically-segregated MSW generally contain fewer metals than sewage sludge used as an agricultural soil improver under controlled conditions. Consequently, the metal content of mechanically-segregated MSW-compost does not represent a barrier to end-use of the product. The application of appropriate preprocessing and refinement technologies is recommended to minimise the contamination of mechanically-segregated MSW-compost as far as practicable. In conclusion, the scientific evidence indicates that conservative, but pragmatic limits on heavy metals in compost may be set to encourage recycling of composted residuals and contaminant reduction measures, which at the same time, also protect the soil and environment from potentially negative impacts caused by long-term accumulation of heavy metals in soil.

Effect of vermicomposting on calcium, sulphur and some heavy metal content of different biodegradable organic wastes under liming and microbial inoculation.

PubMed

Das, Debabrata; Bhattacharyya, Pradip; Ghosh, B C; Banik, Pabitra

2012-01-01

A study was conducted to evaluate the changes in total calcium and sulphur and some heavy metal (Zn, Cu, and Pb) concentration of different organic wastes affected by liming and microorganism inoculation. Vermicomposting was an effective technology for disposal of organic substrates like municipal solid wastes (MSW), possessing comparatively higher concentration of heavy metals. The addition of lime in initial organic substrates significantly (P ≤ 0.05) increased total calcium and total sulphur content of vermicomposts. Inoculation of microorganisms significantly (P ≤ 0.05) reduced the heavy metal content of final products as compared to control. Fungal strains were comparatively more effective in detoxification of heavy metals than B. polymyxa.

Phytotoxicity of tin mine waste and accumulation of involved heavy metals in common buckwheat (Fagopyrum esculentum Moench).

PubMed

Franzaring, Jürgen; Damsohn, Walter; Fangmeier, Andreas; Schlosser, Sonja; Kurz, Hannes; Büttner, Philipp

2018-04-16

Extraction and processing of cassiterite (SnO 2 ) left large tailings with high concentrations of tin, tungsten, molybdenum and lithium. Information on the phytotoxicity of mine waste is important with regard to ecological hazards. Exposure studies help to identify plants useful for the stabilization of waste tips and the phytomining of metals. A greenhouse study was performed using a dilution series of mine waste and four crops, a halophytic and a metallophytic species to derive dose response curves. Based on effective doses for growth reductions, sensitivity increased in the following order: maize > common buckwheat > quinoa > garden bean. Element analyses in different species and compartments of common buckwheat grown in a mixture of standard soil and 25% of the mine waste showed that only low levels of the metals were taken up and that transfer to seed tissues was negligible. As indicated by soil metal levels prior to and after the experiment, only lithium and arsenic proved to be plant available and reached high levels in green tissues while seed levels were low. The experiment confirmed differences in the uptake of metals with regard to elements and species. Common buckwheat is a suited candidate for cultivation on metal polluted soils.

Seasonal changes in chemical and mineralogical composition of sewage sludge incineration residues and their potential for metallic elements and valuable components recovery

NASA Astrophysics Data System (ADS)

Kasina, Monika; Kowalski, Piotr R.; Michalik, Marek

2017-04-01

Increasing energy needs, the implementation of the circular economy principles and rising environmental awareness caused that waste management is becoming a major social and economic issue. The EU Member States have committed to a significant reduction in the amount of waste produced and landfilled and to use their inherent energy and raw materials potential. One of the most reasonable option to fulfil these commitments is waste incineration. The aim of the waste incineration is to reduce their volume and toxicity by disinfection and detoxification at high temperatures. Thermal process and reduction of volume allows the recovery of minerals and metallic elements from residues as well as the energy production (waste-to-energy strategy) during incineration. As a result of waste incineration a variety of solid residues (bottom ash, fly ash, air pollution control residues) and technological waste (gas waste, wastewater) are produced. The goal of this study is to characterize fly ash and air pollution control (APC) residues formed as a result of municipal sewage sludge incineration in terms of their chemical and mineral composition and their extractive potential. Residues were sampled quarterly to study their seasonal changes in composition. The fly ash was a Si-P-C-Fe-Al dominated material, whereas the APC residues composition was dominated by Na-rich soluble phases. The removal of soluble phase ( 98% of the material) from the APC residues by dissolution in deionised water caused significant mass reduction and concentration of non-soluble elements. The main mineral phases in fly ash were quartz, hematite, Fe-PO4, whitlockite and feldspar, while in APC thenardite, and in lower amount calcite, apatite and quartz were present. The chemical composition of fly ash was practically invariable in different seasons, but significant differences were observed in APC residues. The lowest concentrations of all elements and the highest TOC content were measured in the samples collected in the spring 2016. The highest concentrations for most of the elements were measured in summer 2016 except for the Ca, Sn, Zn, Cd, Sb, and Ag which concentrations were the highest in the winter time 2015. Even though the seasonal changes in metallic and/or potentially valuable elements concentrations are visible their overall content is low. In addition they are dispersed within crystalline and amorphous phase, therefore it seems to be inappropriate to consider this material as a source of valuable elements. Due to high phosphorus content in the fly ash, equal to the low grade phosphorus ore, both in the form of phosphate minerals as well as dispersed within minerals can be treated as a potential source of this critical raw material. Acknowledgment: The study was supported by Polish National Science Centre. NCN grant No UMO-2014/15/B/ST10/04171

ECLSS Universal Waste Management System (UWMS) Metal Materials Compatibility Study- Electrochemical and Crevice Corrosion Evaluation

NASA Technical Reports Server (NTRS)

Lee, R. E.

2017-01-01

Electrochemical and crevice corrosion laboratory test results are presented for three noble metal candidates with possible application on the Universal Waste Management System (UWMS) in support of the Environmental Control and Life Support System (ECLSS) aboard the International Space Station (ISS). The three metal candidates, which included Inconel 625, Hastelloy C276 and Titanium 6Al-4V, were evaluated in two solutions representative of the acidic pretreatment formulations utilized during processing of waste liquids within the ECLSS. Final test results and data analysis indicated that the passive layer on all three metals provides excellent corrosion protection in both solutions under standard test conditions.

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

NASA Astrophysics Data System (ADS)

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

2017-11-01

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

Process for vitrification of contaminated sodium oxide

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

Blair, H.T.; Mellinger, G.B.

1983-03-01

A glass composition was developed to accommodate 30 wt % sodium oxide and resist devitrification and leaching. An in-can melting process that is compatible with a comtaminated sodium calciner developed by Argonne National Laboratory was tested both on a laboratory and on an engineering scale and found to be viable. The Liquid Metal Fast Breeder Reactor experimental program continues to produce elemental sodium contaminated with radionuclides. This material is presently in temporary storage facilities because the current criterion will not permit alkali metals to be disposed of in shallow land burials. As a first step in treatment, Argonne National Laboratorymore » (ANL) has developed a calciner that will convert the sodium metal to an oxide. In work supported by the U.S. Department of Energy, Pacific Northwest Laboratory (PNL) is developing and demonstrating a process that is compatible with the calciner and facilities at ANL-West for incorporating sodium oxide into a glass. Glass, which normally contains sodium oxide, was chosen as the waste form because it is chemically durable and nondispersible. It is simple to produce, and the technology for incorporating nuclear wastes into glass is well developed.« less

Metal-binding hydrogel particles alleviate soil toxicity and facilitate healthy plant establishment of the native metallophyte grass Astrebla lappacea in mine waste rock and tailings.

PubMed

Bigot, M; Guterres, J; Rossato, L; Pudmenzky, A; Doley, D; Whittaker, M; Pillai-McGarry, U; Schmidt, S

2013-03-15

Soil contaminants are potentially a major threat to human and ecosystem health and sustainable production of food and energy where mineral processing wastes are discharged into the environment. In extreme conditions, metal concentrations in wastes often exceed even the metal tolerance thresholds of metallophytes (metal-tolerant plants) and sites remain barren with high risks of contaminant leaching and dispersion into the environment via erosion. A novel soil amendment based on micron-size thiol functional cross-linked acrylamide polymer hydrogel particles (X3) binds toxic soluble metals irreversibly and significantly reduces their concentrations in the soil solution to below the phytotoxicity thresholds. X3 mixed into the top 50mm of phytotoxic mine waste materials in pots in glasshouse conditions reduced total soluble concentrations of toxic contaminants by 90.3-98.7% in waste rock, and 88.6-96.4% in tailings immediately after application. After 61 days, quality of unamended bottom layer of X3-treated pots was also significantly improved in both wastes. Combination of X3 and metallophytes was more efficient at improving soil solution quality than X3 alone. Addition of X3 to substrates increased substrate water retention and water availability to plants by up to 108% and 98% for waste rock and tailings respectively. Soil quality improvement by X3 allowed successful early establishment of the native metallophyte grass Astrebla lappacea on both wastes where plants failed to establish otherwise. Copyright © 2013 Elsevier B.V. All rights reserved.

Controls on the Mobility of Antimony in Mine Waste from Three Deposit Types

NASA Astrophysics Data System (ADS)

Jamieson, H.; Radková, A. B.; Fawcett, S.

2017-12-01

Antimony can be considered both a critical metal and an environmental hazard, with a toxicity similar to arsenic. It is concentrated in stibnite deposits, but also present in polymetallic and precious metal ores, frequently accompanied by arsenic. We have studied the mineralogical controls on the mobility of antimony in three types of mine waste: stibnite tailings from an antimony mine, tetrahedrite-bearing waste rock from copper mining, and gold mine tailings and ore roaster waste. Our results demonstrate that the tendency of antimony to leach into the aqueous environment or remain sequestered in solid phases depends on the primary host minerals and conditions governing the precipitation of secondary antimony-hosting phases. In tailings at the Beaver Brook antimony mine in Newfoundland, Canada, stibnite oxidizes rapidly, and secondary minerals such as the relatively insoluble Sb-Fe tripuhyite-like phase and Sb-bearing goethite. However, under dry conditions, the most important secondary Sb host is the Mg-Sb hydroxide brandholzite, but this easily soluble mineral disappears when it rains. Antimony that was originally hosted in tetrahedrite, a complex multi-element sulfosalt, in the historic waste rock piles at Špania Dolina-Piesky, Slovakia, is not as mobile as Cu and As during weathering but reprecipiates to a mixture of tripuhyite and romeite. Finally, the original antimony-hosting minerals, both stibnite and sulphosalts, in the gold ore at Giant Mine, Yellowknife, Canada were completely destroyed during ore roasting. In tailings-contaminated sediments, antimony persists in roaster-generated iron oxide phases, except under reducing conditions where some of the antimony forms a Sb-S phase. The combined presence of antimony and arsenic in mine waste complicates risk assessment but in general, our findings suggest that antimony is less mobile than arsenic in the environment.

Speciation and leaching of trace metal contaminants from e-waste contaminated soils.

PubMed

Cui, Jin-Li; Luo, Chun-Ling; Tang, Chloe Wing-Yee; Chan, Ting-Shan; Li, Xiang-Dong

2017-05-05

Primitive electrical and electronic waste (e-waste) recycling activities have caused serious environmental problems. However, little is known about the speciation and leaching behaviors of metal contaminants at e-waste contaminated sites. This study investigated trace metal speciation/mobilization from e-waste polluted soil through column leaching experiments involving irrigation with rainwater for almost 2.5 years. Over the experimental period, Cu and Zn levels in the porewater were 0.14±0.08mg/L, and 0.16±0.08mg/L, respectively, increasing to 0.33±0.16mg/L, and 0.69±0.28mg/L with plant growth. The amounts of Cu, Zn, and Pb released in surface soil (0-2cm) contributed 43.8%, 22.5%, and 13.8%, respectively, to the original levels. The released Cu and Zn were primarily caused by the mobilization of the carbonate species of metals, including Cu(OH) 2 , CuCO 3 , and Zn 5 (CO 3 ) 2 (OH) 6 , and amorphous Fe/Mn oxides associated fractions characterized by sequential extraction coupling with X-ray absorption spectroscopy. During the experiments, trace metals were not detected in the effluent, and the re-sequestration of trace metals was mainly attributed to the adsorption on the abundant Fe/Mn oxides in the sub-layer soil. This study quantitatively elucidated the molecular speciation of Cu and Zn in e-waste contaminated soil during the column leaching process. Copyright © 2017 Elsevier B.V. All rights reserved.

Sequential Extraction Results and Mineralogy of Mine Waste and Stream Sediments Associated With Metal Mines in Vermont, Maine, and New Zealand

USGS Publications Warehouse

Piatak, N.M.; Seal, R.R.; Sanzolone, R.F.; Lamothe, P.J.; Brown, Z.A.; Adams, M.

2007-01-01

We report results from sequential extraction experiments and the quantitative mineralogy for samples of stream sediments and mine wastes collected from metal mines. Samples were from the Elizabeth, Ely Copper, and Pike Hill Copper mines in Vermont, the Callahan Mine in Maine, and the Martha Mine in New Zealand. The extraction technique targeted the following operationally defined fractions and solid-phase forms: (1) soluble, adsorbed, and exchangeable fractions; (2) carbonates; (3) organic material; (4) amorphous iron- and aluminum-hydroxides and crystalline manganese-oxides; (5) crystalline iron-oxides; (6) sulfides and selenides; and (7) residual material. For most elements, the sum of an element from all extractions steps correlated well with the original unleached concentration. Also, the quantitative mineralogy of the original material compared to that of the residues from two extraction steps gave insight into the effectiveness of reagents at dissolving targeted phases. The data are presented here with minimal interpretation or discussion and further analyses and interpretation will be presented elsewhere.

Heavy metals contamination and their risk assessment around the abandoned base metals and Au-Ag mines in Korea

NASA Astrophysics Data System (ADS)

Chon, Hyo-Taek

2017-04-01

Heavy metals contamination in the areas of abandoned Au-Ag and base metal mines in Korea was investigated in order to assess the level of metal pollution, and to draw general summaries about the fate of toxic heavy metals in different environments. Efforts have been made to compare the level of heavy metals, chemical forms, and plant uptake of heavy metals in each mine site. In the base-metals mine areas, significant levels of Cd, Cu, Pb and Zn were found in mine dump soils developed over mine waste materials and tailings. Leafy vegetables tend to accumulate heavy metals(in particular, Cd and Zn) higher than other crop plants, and high metal concentrations in rice crops may affect the local residents' health. In the Au-Ag mining areas, arsenic would be the most characteristic contaminant in the nearby environment. Arsenic and heavy metals were found to be mainly associated with sulfide gangue minerals, and the mobility of these metals would be enhanced by the effect of continuing weathering and oxidation. According to the sequential extraction of metals in soils, most heavy metals were identified as non-residual chemical forms, and those are very susceptible to the change of ambient conditions of a nearby environment. The concept of pollution index(PI) of soils gives important information on the extent and degree of multi-element contamination, and can be applied to the evaluation of mine soils before their agricultural use and remediation. The risk assessment process comprising exposure assessment, dose-response assessment, and risk characterization was discussed, and the results of non-cancer risk of As, Cd, and Zn, and those of cancer risk of As were suggested.

Studying microfungi-mineral interactions in sulphide-bearing waste-rock dumps: a 7 years survey in the Libiola mine, North-Eastern Italy

NASA Astrophysics Data System (ADS)

Marescotti, P.; Cecchi, G.; Di Piazza, S.; Lucchetti, G.; Zotti, M.

2015-12-01

Sulphide-bearing waste-rock dumps represent complex geological systems characterised by high percentages of low-grade mineralisations and non-valuable sulphides (such as pyrite and pyrrhotite). The sulphide oxidation triggers acid mine drainage (AMD) processes and the release of several metals of environmental concern. The severe physicochemical properties of these metal-contaminated environments tend to inhibit soil forming processes and represent an important stress factor for the biotic communities by exerting a strong selective pressure. Some macro- and micro-fungi are pioneer and extremophile organisms, which may survive and tolerate high concentrations of toxic metals in contaminated environments. Many studies show the fungal capability to bioaccumulate, biosorb, and store in their cells a high concentration of ecotoxic metals. A 7 years multidisciplinary survey was carried out in the Libiola sulphide mine. The results evidenced that the waste rock dumps of the area are characterized by an extremely poor flora and a specific mycobiota, due to the soil acidity, high concentration of trace metals, and unavailability or paucity of nutrients and organic matter. Our studies allowed the complete mineralogical, geochemical, and mycological characterization of one of the biggest dumps of the mine. 30 microfungal vital strains were isolated in pure cultures and studied with molecular and morphological approach, for their identification. The results allowed the isolation of some rare and important extremophilic species. Penicillium was the most recurrent genus, together with Trichoderma and Cladosporium. In particular, Penicillium glandicola is a rare species previously isolated from cave or arid environments, whereas P. brevicompactum is one of the most important fungi for metal corrosion. Hence, some bioaccumulation tests allowed to select a Trichoderma harzianum strain efficient to uptake Cu and Ag from pyrite-bearing soils, highlighting its central role in fungal remediation protocol. Further studies are in progress to investigate the potential interactions between microfungi and sulphides from the Libiola mine soils and to evaluate the fungal role in the biomineralisation and deactivation/mobilisation of toxic metals.

Extractive waste management: A risk analysis approach.

PubMed

Mehta, Neha; Dino, Giovanna Antonella; Ajmone-Marsan, Franco; Lasagna, Manuela; Romè, Chiara; De Luca, Domenico Antonio

2018-05-01

Abandoned mine sites continue to present serious environmental hazards because the heavy metals associated with extractive waste are continuously released into the environment, where they threaten human life and the environment. Remediating and securing extractive waste are complex, lengthy and costly processes. Thus, in most European countries, a site is considered for intervention when it poses a risk to human health and the surrounding environment. As a consequence, risk analysis presents a viable decisional approach towards the management of extractive waste. To evaluate the effects posed by extractive waste to human health and groundwater, a risk analysis approach was used for an abandoned nickel extraction site in Campello Monti in North Italy. This site is located in the Southern Italian Alps. The area consists of large and voluminous mafic rocks intruded by mantle peridotite. The mining activities in this area have generated extractive waste. A risk analysis of the site was performed using Risk Based Corrective Action (RBCA) guidelines, considering the properties of extractive waste and water for the properties of environmental matrices. The results showed the presence of carcinogenic risk due to arsenic and risks to groundwater due to nickel. The results of the risk analysis form a basic understanding of the current situation at the site, which is affected by extractive waste. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterisation of metals in the electronic waste of complex mixtures of end-of-life ICT products for development of cleaner recovery technology

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

Sun, Z.H.I.; Xiao, Y.; Sietsma, J.

2015-01-15

Highlights: • New characterisation methodology has been established to understand an industrially processed ICT waste. • Particle size distribution, composition, thermal–chemical behaviour and occurrence of metals were considered. • The characterisation provides direct guidelines for values recovery from the waste. - Abstract: Recycling of valuable metals from electronic waste, especially complex mixtures of end-of-life information and communication technology (ICT) products, is of great difficulty due to their complexity and heterogeneity. One of the important reasons is the lack of comprehensive characterisation on such materials, i.e. accurate compositions, physical/chemical properties. In the present research, we focus on developing methodologies for themore » characterisation of metals in an industrially processed ICT waste. The morphology, particle size distribution, compositional distribution, occurrence, liberation as well as the thermo-chemical properties of the ICT waste were investigated with various characterisation techniques, including X-ray Fluorescence Spectrometry (XRF), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) with energy dispersed spectroscopy (EDS). Due to the high heterogeneity of the material, special sample preparation procedures were introduced to minimise the discrepancies during compositional analyses. As a result, a clearer overview of the ICT waste has been reached. This research provides better understanding of the extractability of each metal and improves the awareness of potential obstacles for extraction. It will lead to smarter decisions during further development of a clean and effective recovery process.« less

Environmental assessment of mining industry solid pollution in the mercurial district of Azzaba, northeast Algeria.

PubMed

Seklaoui, M'hamed; Boutaleb, Abdelhak; Benali, Hanafi; Alligui, Fadila; Prochaska, Walter

2016-11-01

To date, there have been few detailed studies regarding the impact of mining and metallogenic activities on solid fractions in the Azzaba mercurial district (northeast Algeria) despite its importance and global similarity with large Hg mines. To assess the degree, distribution, and sources of pollution, a physical inventory of apparent pollution was developed, and several samples of mining waste, process waste, sediment, and soil were collected on regional and local scales to determine the concentration of Hg and other metals according to their existing mineralogical association. Several physico-chemical parameters that are known to influence the pollution distribution are realized. The extremely high concentrations of all metals exceed all norms and predominantly characterize the metallurgic and mining areas; the metal concentrations significantly decrease at significant low distances from these sources. The geo-accumulation index, which is the most realistic assessment method, demonstrates that soils and sediments near waste dumps and abandoned Hg mines are extremely polluted by all analyzed metals. The pollution by these metals decreases significantly with distance, which indicates a limited dispersion. The results of a clustering analysis and an integrated pollution index suggest that waste dumps, which are composed of calcine and condensation wastes, are the main source of pollution. Correlations and principal component analysis reveal the important role of hosting carbonate rocks in limiting pollution and differentiating calcine wastes from condensation waste, which has an extremely high Hg concentration (˃1 %).

Innovative Concept for the Recovery of Silver and Indium by a Combined Treatment of Jarosite and Electric Arc Furnace Dust

NASA Astrophysics Data System (ADS)

Wegscheider, S.; Steinlechner, S.; Leuchtenmüller, M.

2017-02-01

Industrial wastes such as slags, dust, or precipitation residues contain significant amounts of valuable metals like zinc, lead, and copper as well as precious metals like silver and indium. Nevertheless, a lot of these waste materials are not recycled, and therefore, many valuable metals end up being sent to landfills. Because of harmful components in the waste, it is often necessary to send it to specialized landfills for hazardous wastes, which leads to environmental problems as well as additional costs. Consequently, the recovery of the valuable metals from the residues represents a sensible task to decrease the negative impact on the environment and to reduce costs for maintaining a landfill. In addition, recycling helps to decrease the dependency from primary resources. The present study deals with the behavior of different metals in a pyro-metallurgical treatment for a mixture of jarosite and electric arc furnace dust with a special focus on indium and silver.

Hazardous waste status of discarded electronic cigarettes.

PubMed

Krause, Max J; Townsend, Timothy G

2015-05-01

The potential for disposable electronic cigarettes (e-cigarettes) to be classified as hazardous waste was investigated. The Toxicity Characteristic Leaching Procedure (TCLP) was performed on 23 disposable e-cigarettes in a preliminary survey of metal leaching. Based on these results, four e-cigarette products were selected for replicate analysis by TCLP and the California Waste Extraction Test (WET). Lead was measured in leachate as high as 50mg/L by WET and 40mg/L by TCLP. Regulatory thresholds were exceeded by two of 15 products tested in total. Therefore, some e-cigarettes would be toxicity characteristic (TC) hazardous waste but a majority would not. When disposed in the unused form, e-cigarettes containing nicotine juice would be commercial chemical products (CCP) and would, in the United States (US), be considered a listed hazardous waste (P075). While household waste is exempt from hazardous waste regulation, there are many instances in which such waste would be subject to regulation. Manufactures and retailers with unused or expired e-cigarettes or nicotine juice solution would be required to manage these as hazardous waste upon disposal. Current regulations and policies regarding the availability of nicotine-containing e-cigarettes worldwide were reviewed. Despite their small size, disposable e-cigarettes are consumed and discarded much more quickly than typical electronics, which may become a growing concern for waste managers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Immobilization of metals in contaminated soil from E-waste recycling site by dairy-manure-derived biochar.

PubMed

Chen, Zhiliang; Zhang, Jianqiang; Liu, Minchao; Wu, Yingxin; Yuan, Zhihui

2017-08-24

E-waste is a growing concern around the world and varieties of abandoned E-waste recycling sites, especially in urban area, need to remediate immediately. The impacts of dairy-manure-derived biochars (BCs) on the amelioration of soil properties, the changes in the morphologies as well as the mobility of metals were studied to test their efficacy in immobilization of metals for a potential restoration of vegetation landscape in abandoned E-waste recycling site. The amendment with BCs produced positive effects on bioavailability and mobility reduction for Pb, Cd, Zn and Cu depending on BC ratio and incubation time. The BCs promoted the transformation of species of heavy metals to a more stable fraction, and the metals concentrations in Toxicity Characteristic Leaching Procedure extract declined significantly, especially Pb and Cu. Besides, the BCs ameliorated the substrate with increasing the soil pH, cations exchangeable capacity and available phosphorous, which suggested BC as a potential amendment material for abandoned E-waste recycling sites before restoration of vegetation landscape. Generally, the BC modified by alkaline treatment has a higher efficacy, probably due to increase of specific surface area and porosity as well as the functional groups after alkaline treatment.

Hydrometallurgical Recovery of Metals from Large Printed Circuit Board Pieces.

PubMed

Jadhav, U; Hocheng, H

2015-09-29

The recovery of precious metals from waste printed circuit boards (PCBs) is an effective recycling process. This paper presents a promising hydrometallurgical process to recover precious metals from waste PCBs. To simplify the metal leaching process, large pieces of PCBs were used instead of a pulverized sample. The chemical coating present on the PCBs was removed by sodium hydroxide (NaOH) treatment prior to the hydrometallurgical treatment. Among the leaching reagents examined, hydrochloric acid (HCl) showed great potential for the recovery of metals. The HCl-mediated leaching of waste PCBs was investigated over a range of conditions. Increasing the acid concentration decreased the time required for complete metal recovery. The shaking speed showed a pronounced positive effect on metal recovery, but the temperature showed an insignificant effect. The results showed that 1 M HCl recovered all of the metals from 4 cm × 4 cm PCBs at room temperature and 150 rpm shaking speed in 22 h.

Hydrometallurgical Recovery of Metals from Large Printed Circuit Board Pieces

PubMed Central

Jadhav, U.; Hocheng, H.

2015-01-01

The recovery of precious metals from waste printed circuit boards (PCBs) is an effective recycling process. This paper presents a promising hydrometallurgical process to recover precious metals from waste PCBs. To simplify the metal leaching process, large pieces of PCBs were used instead of a pulverized sample. The chemical coating present on the PCBs was removed by sodium hydroxide (NaOH) treatment prior to the hydrometallurgical treatment. Among the leaching reagents examined, hydrochloric acid (HCl) showed great potential for the recovery of metals. The HCl-mediated leaching of waste PCBs was investigated over a range of conditions. Increasing the acid concentration decreased the time required for complete metal recovery. The shaking speed showed a pronounced positive effect on metal recovery, but the temperature showed an insignificant effect. The results showed that 1 M HCl recovered all of the metals from 4 cm × 4 cm PCBs at room temperature and 150 rpm shaking speed in 22 h. PMID:26415827

Limitation of tritium outgassing from tritiated solid waste drums

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

Liger, K.; Trabuc, P.; Lefebvre, X.

2015-03-15

In the framework of the development of fusion thermonuclear reactors, tritiated solid waste is foreseen and will have to be managed. The management of tritiated waste implies limitations in terms of activity and tritium degassing. The degassing tritium can be under the form of tritiated hydrogen, tritiated water and, in some specific cases, negligible amount of tritiated volatile organic compound. Hence, considering the major forms of degassing tritium, CEA has developed a mixed-compound dedicated to tritium trapping in drums. Based on several experiments, the foreseen mixed compound is composed of MnO{sub 2}, Ag{sub 2}O, Pt and molecular sieve, the threemore » first species having the ability to convert tritiated hydrogen into tritiated water and the last one acting as a trap for tritiated water. To assess the performance of the trapping mixture, experimental tests were performed at room temperature on tritiated dust composed of beryllium and carbon. It was shown that the metallic oxides mixture used for tritiated hydrogen conversion is efficient and that tritiated water adsorption was limited due to an inefficient regeneration of the molecular sieve prior to its use. Apart from this point, the tritium release from waste was reduced by a factor of 5.5, which can be improved up to 87 if the adsorption step is efficient.« less

[Correlation of Persistent Free Radicals, PCDD/Fs and Metals in Waste Incineration Fly Ash].

PubMed

Wang, Tian-jiao; Chen, Tong; Zhan, Ming-xiu; Guo, Ying; Li, Xiao-dong

2016-03-15

Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.

Colloids from the aqueous corrosion of uranium nuclear fuel

NASA Astrophysics Data System (ADS)

Kaminski, M. D.; Dimitrijevic, N. M.; Mertz, C. J.; Goldberg, M. M.

2005-12-01

Colloids may enhance the subsurface transport of radionuclides and potentially compromise the long-term safe operation of the proposed radioactive waste repository at Yucca Mountain. Little data is available on colloid formation for the many different waste forms expected to be buried in the repository. This work expands the sparse database on colloids formed during the corrosion of metallic uranium nuclear fuel. We characterized spherical UO 2 and nickel-rich montmorilonite smectite-clay colloids formed during the corrosion of uranium metal fuel under bathtub conditions at 90 °C. Iron and chromium oxides and calcium carbonate colloids were present but were a minor population. The estimated upper concentration of the UO 2 and clays was 4 × 10 11 and 7 × 10 11-3 × 10 12 particles/L, respectively. However, oxygen eventually oxidized the UO 2 colloids, forming long filaments of weeksite K 2(UO 2) 2Si 6O 15 · 4H 2O that settled from solution, reducing the UO 2 colloid population and leaving predominantly clay colloids. The smectite colloids were not affected by oxygen. Plutonium was not directly observed within the UO 2 colloids but partitioned completely to the colloid size fraction. The plutonium concentration in the colloidal fraction was slightly higher than the value used in the viability assessment model, and does not change in concentration with exposure to oxygen. This paper provides conclusive evidence for single-phase radioactive colloids composed of UO 2. However, its impact on repository safety is probably small since oxygen and silica availability will oxidize and effectively precipitate the UO 2 colloids from concentrated solutions.

ELECTROLYTIC REDUCTION OF NITRIC ACID SOLUTIONS

DOEpatents

Alter, H.W.; Barney, D.L.

1958-09-30

A process is presented for the treatment of radioactivc waste nitric acid solutions. The nitric acid solution is neutralized with an alkali metal hydroxide in an amount sufficient to precipitate insoluble hydroxides, and after separation of the precipitate the solution is electrolyzed to convert the alkali nitrate formed, to alkali hydroxide, gaseous ammonla and oxygen. The solution is then reusable after reducing the volume by evaporating the water and dissolved ammonia.

The carbonaceous sorbent based on the secondary silica-containing material from oil extraction industry

NASA Astrophysics Data System (ADS)

Starostina, I. V.; Stolyarov, D. V.; Anichina, Ya N.; Porozhnyuk, E. V.

2018-01-01

The object of research in this work is the silica-containing waste of oil extraction industry - the waste kieselghur (diatomite) sludge from precoat filtering units, used for the purification of vegetable oils from organic impurities. As a result of the thermal modification of the sludge, which contains up to 70% of organic impurities, a finely-dispersed low-porous carbonaceous mineral sorption material is formed. The modification of the sludge particles surface causes the substantial alteration of its physical, chemical, adsorption and structural properties - the organic matter is charred, the particle size is reduced, and on the surface of diatomite particles a carbon layer is formed, which deposits in macropores and partially occludes them. The amount of mesopores is increased, along with the specific surface of the obtained product. The optimal temperature of sludge modification is 500°C. The synthesized carbonaceous material can be used as an adsorbing agent for the purification of wastewater from heavy metal ions. The sorption capacity of Cu2+ ions amounted to 14.2 mg·g-1 and for Ni2+ ions - 17.0 mg·g-1. The obtained values exceed the sorption capacity values of the initial kieselghur, used as a filtering charge, for the researched metal ions.

Silicotitanate molecular sieve and condensed phases

DOEpatents

Nenoff, Tina M.; Nyman, May D.

2002-01-01

A new microporous crystalline molecular sieve material having the formula Cs.sub.3 TiSi.sub.3 O.sub.95.cndot.3H.sub.2 O and its hydrothermally condensed phase, Cs.sub.2 TiSi.sub.6 O.sub.15, are disclosed. The microporous material can adsorb divalent ions of radionuclides or other industrial metals such as chromium, nickel, lead, copper, cobalt, zinc, cadmium, barium, and mercury, from aqueous or hydrocarbon solutions. The adsorbed metal ions can be leached out for recovery purposes or the microporous material can be hydrothermally condensed to a radiation resistant, structurally and chemically stable phase which can serve as a storage waste form for radionuclides.

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

DTIC Science & Technology

2010-01-21

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

Identifying Metals as Marker for Waste Burning Aerosol Particles in New Delhi

NASA Astrophysics Data System (ADS)

Kumar, Sudhanshu

2012-07-01

{Identifying Metals as Marker for Waste Burning Aerosol Particles in New Delhi } Tracing of aerosol sources is an important task helpful for making control strategy, and for climate change study. However, it is a difficult job as aerosols have several sources, involve in complex atmospheric processing, degradation and removal processes. Several approaches have been used for this task, e.g., models, which are based on the input of chemical species; stable- and radio-isotope compositions of certain species; chemical markers in which trace metals are the better options because they persist in atmosphere until the life of a particle. For example, K and Hg are used for biomass and coal burning tracings, respectively. Open waste burning has recently been believed to be a considerable source of aerosols in several mega cities in India and China. To better understand this source contribution in New Delhi aerosols, we have conducted aerosol sampling at a landfill site (Okhla), and in proximity (within 1 km distance) of this site. Aerosol filter samples were acid digested in microwave digestion system and analyzed using inductively coupled plasma -- high resolution mass spectrometry (ICP-HRMS) for getting metal signatures in particles. The metals, e.g., Sn, Sb and As those are found almost negligible in remote aerosols, are maximized in these waste burning aerosols. Sample collected in other location of New Delhi also shows the considerable presence of these metals in particles. Preliminary studies of isotopic ratios of these metals suggested that these metals, especially Sn can be used as marker for tracing the open waste burning sources of aerosols in New Delhi.

Comparative evaluation of short-term leach tests for heavy metal release from mineral processing waste

USGS Publications Warehouse

Al-Abed, S. R.; Hageman, P.L.; Jegadeesan, G.; Madhavan, N.; Allen, D.

2006-01-01

Evaluation of metal leaching using a single leach test such as the Toxicity Characteristic Leaching Procedure (TCLP) is often questionable. The pH, redox potential (Eh), particle size and contact time are critical variables in controlling metal stability, not accounted for in the TCLP. This paper compares the leaching behavior of metals in mineral processing waste via short-term extraction tests such as TCLP, Field Leach Test (FLT) used by USGS and deionized water extraction tests. Variation in the extracted amounts was attributed to the use of different particle sizes, extraction fluid and contact time. In the controlled pH experiments, maximum metal extraction was obtained at acidic pH for cationic heavy metals such as Cu, Pb and Zn, while desorption of Se from the waste resulted in high extract concentrations in the alkaline region. Precipitation of iron, caused by a pH increase, probably resulted in co-precipitation and immobilization of Cu, Pb and Zn in the alkaline pH region. A sequential extraction procedure was performed on the original waste and the solid residue from the Eh-pH experiments to determine the chemical speciation and distribution of the heavy metals. In the as-received waste, Cu existed predominantly in water soluble or sulfidic phases, with no binding to carbonates or iron oxides. Similar characteristics were observed for Pb and Zn, while Se existed mostly associated with iron oxides or sulfides. Adsorption/co-precipitation of Cu, Se and Pb on precipitated iron hydroxides was observed in the experimental solid residues, resulting in metal immobilization above pH 7.

40 CFR 60.52b - Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2013 CFR

2013-07-01

... metals, acid gases, organics, and nitrogen oxides. 60.52b Section 60.52b Protection of Environment... § 60.52b Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a... (total mass), corrected to 7 percent oxygen. (d) The limits for nitrogen oxides are specified in...

40 CFR 60.52b - Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2012 CFR

2012-07-01

... metals, acid gases, organics, and nitrogen oxides. 60.52b Section 60.52b Protection of Environment... § 60.52b Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a... (total mass), corrected to 7 percent oxygen. (d) The limits for nitrogen oxides are specified in...

40 CFR 60.52b - Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2011 CFR

2011-07-01

... metals, acid gases, organics, and nitrogen oxides. 60.52b Section 60.52b Protection of Environment... § 60.52b Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a... (total mass), corrected to 7 percent oxygen. (d) The limits for nitrogen oxides are specified in...

40 CFR 60.52b - Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2014 CFR

2014-07-01

... metals, acid gases, organics, and nitrogen oxides. 60.52b Section 60.52b Protection of Environment... § 60.52b Standards for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a... (total mass), corrected to 7 percent oxygen. (d) The limits for nitrogen oxides are specified in...

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

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

This paper provides an overview of research evaluating the use of tellurite glass as a waste form for salt wastes from electrochemical processing. The capacities to immobilize different salts were evaluated including: a LiCl-Li2O oxide reduction salt (for oxide fuel) containing fission products, a LiCl-KCl eutectic salt (for metallic fuel) containing fission products, and SrCl2. Physical and chemical properties of the glasses were characterized by using X-ray diffraction, bulk density measurements, chemical durability tests, scanning electron microscopy, and energy dispersive X-ray emission spectroscopy. These glasses were found to accommodate high concentrations of halide salts and have high densities. However, improvementsmore » are needed to meet chemical durability requirements.« less

The pH-dependent leaching behavior of slags from various stages of a copper smelting process: Environmental implications.

PubMed

Jarošíková, Alice; Ettler, Vojtěch; Mihaljevič, Martin; Kříbek, Bohdan; Mapani, Ben

2017-02-01

The leaching behaviors of primary copper (Cu) slags originating from Ausmelt, reverbatory, and converter furnaces operating under a single technological process were compared to a residual slag tailing obtained by slag re-processing via flotation and metal recovery. The EN 12457-2 leaching test, used for assessment of the hazardous properties, was followed by the CEN/TS 14997 pH-static leaching test (pH range 3-12). Both leaching experiments were coupled with a mineralogical investigation of the primary and secondary phases as well as geochemical modeling. Metals (Cd, Cu, Pb, Zn) exhibit the highest leaching at low pH. Under acidic conditions (pH 3-6), Ausmelt slag and slag tailing exhibited higher metal leaching compared to other slag types. Very low leaching of metals (far below EU limits for non-hazardous waste) was observed at natural pH (7.9-9.0) for all the studied slag samples. In contrast, relatively high leaching of As was observed over the entire pH range, especially for Ausmelt slag (exceeding the EU limit for hazardous waste by 1.7×). However, geochemical modeling and scanning electron microscopy indicated that formation of stable Ca-Cu-Pb arsenates and the binding of As to newly formed Fe (oxyhydr)oxides play an important role in efficient As immobilization at the slag-water interface. In contrast, no controls were predicted for Sb, whose leaching was almost pH-independent. Nevertheless Sb leached concentrations at natural pH were below EU limit for hazardous waste. Re-processing of primary Cu slags for metal recovery, and subsequent co-disposal of the resulting slag tailing with dolomite-rich mine tailing and local laterite is suitable for stabilizing the remaining contaminants (except Sb) and limiting their leaching into the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: implications for dissemination of heavy metals.

PubMed

Wu, Qihang; Leung, Jonathan Y S; Geng, Xinhua; Chen, Shejun; Huang, Xuexia; Li, Haiyan; Huang, Zhuying; Zhu, Libin; Chen, Jiahao; Lu, Yayin

2015-02-15

Illegal e-waste recycling activity has caused heavy metal pollution in many developing countries, including China. In recent years, the Chinese government has strengthened enforcement to impede such activity; however, the heavy metals remaining in the abandoned e-waste recycling site can still pose ecological risk. The present study aimed to investigate the concentrations of heavy metals in soil and water in the vicinity of an abandoned e-waste recycling site in Longtang, South China. Results showed that the surface soil of the former burning and acid-leaching sites was still heavily contaminated with Cd (>0.39 mg kg(-1)) and Cu (>1981 mg kg(-1)), which exceeded their respective guideline levels. The concentration of heavy metals generally decreased with depth in both burning site and paddy field, which is related to the elevated pH and reduced TOM along the depth gradient. The pond water was seriously acidified and contaminated with heavy metals, while the well water was slightly contaminated since heavy metals were mostly retained in the surface soil. The use of pond water for irrigation resulted in considerable heavy metal contamination in the paddy soil. Compared with previous studies, the reduced heavy metal concentrations in the surface soil imply that heavy metals were transported to the other areas, such as pond. Therefore, immediate remediation of the contaminated soil and water is necessary to prevent dissemination of heavy metals and potential ecological disaster. Copyright © 2014 Elsevier B.V. All rights reserved.

Geochemical characterization of slags, other mines wastes, and their leachates from the Elizabeth and Ely mines (Vermont), the Ducktown mining district (Tennessee), and the Clayton smelter site (Idaho)

USGS Publications Warehouse

Piatak, Nadine M.; Seal, Robert R.; Hammarstrom, Jane M.; Meier, Allen L.; Briggs, Paul H.

2003-01-01

Waste-rock material produced at historic metal mines contains elevated concentrations of potentially toxic trace elements. Two types of mine waste were examined in this study: sintered waste rock and slag. The samples were collected from the Elizabeth and Ely mines in the Vermont copper belt (Besshi-type massive sulfide deposits), from the Copper Basin mining district near Ducktown, Tennessee (Besshi-type massive sulfide deposits), and from the Clayton silver mine in the Bayhorse mining district, Idaho (polymetallic vein and replacement deposits). The data in this report are presented as a compilation with minimal interpretation or discussion. A detailed discussion and interpretation of the slag data are presented in a companion paper. Data collected from sintered waste rock and slag include: (1) bulk rock chemistry, (2) mineralogy, (3) and the distribution of trace elements among phases for the slag samples. In addition, the reactivity of the waste material under surficial conditions was assessed by examining secondary minerals formed on slag and by laboratory leaching tests using deionized water and a synthetic solution approximating precipitation in the eastern United States.

Toxic metals in WEEE: characterization and substance flow analysis in waste treatment processes.

PubMed

Oguchi, Masahiro; Sakanakura, Hirofumi; Terazono, Atsushi

2013-10-01

Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. Copyright © 2012 Elsevier B.V. All rights reserved.

Method for producing chemically bonded phosphate ceramics and for stabilizing contaminants encapsulated therein utilizing reducing agents

DOEpatents

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

2000-01-01

Known phosphate ceramic formulations are improved and the ability to produce iron-based phosphate ceramic systems is enabled by the addition of an oxidizing or reducing step during the acid-base reactions that form the phosphate ceramic products. The additives allow control of the rate of the acid-base reactions and concomitant heat generation. In an alternate embodiment, waste containing metal anions are stabilized in phosphate ceramic products by the addition of a reducing agent to the phosphate ceramic mixture. The reduced metal ions are more stable and/or reactive with the phosphate ions, resulting in the formation of insoluble metal species within the phosphate ceramic matrix, such that the resulting chemically bonded phosphate ceramic product has greater leach resistance.

Rubber industry

NASA Astrophysics Data System (ADS)

Staszak, Maciej

2018-03-01

Following chapter presents short introductory description of rubber and rubber industry. The main problem of rubber industry is the way of the usage of spent tires. Furthermore very important group of problems arise considering the metal and nonmetal additives which are significant component of the vulcanized rubber. The key attention is dedicated to typical ways of rubber usage in utilization and recovery of metals from spent rubber materials concentrating specifically on used tires processing. The method of recovery of rare metals from rubber tires was described. The rubber debris finds widest use in the field of waste metal solutions processing. The environmental pollution caused by metals poses serious threat to humans. Several applications of the use of waste rubber debris to remove metals from environmental waters were described. Moreover, the agriculture usage of waste tire rubber debris is described, presenting systems where the rubber material can be useful as a soil replacement.

Thermal immobilization of Cr, Cu and Zn of galvanizing wastes in the presence of clay and fly ash.

PubMed

Singh, I B; Chaturvedi, K; Yegneswaran, A H

2007-07-01

In the present investigation thermal treatment of galvanizing waste with clay and fly ash has been carried out to immobilize Cr, Zn, Cu and other metals of the waste at temperature range 850 degrees C to 950 degrees C. Leaching of the metals from the waste and solidified product was analyzed using toxic characteristic leaching procedure (TCLP). Results indicated that the composition of waste and clay treatment temperature are the key factors in determining the stability of solidified product. After heating at 950 degrees C, the solidified specimens of 10% waste with clay have shown comparatively a high compressive strength and less water absorption. However, a decrease in compressive strength and increase in water absorption were noticed after addition of 15% of waste with clay. The leachability of all the metals present in the waste was found to reduce considerably with the increase of treatment temperature. In the case of Cr and Zn, their leachabilty was found at unacceptable levels from the treated product obtained after heating at 850 degrees C However, their leachability was reduced significantly within an acceptable level after treatment at 950 degrees C. The thermal treatment has shown an increase of re-oxidation trend of Cr (III) to Cr (VI) up to 900 degrees C of heating and this trend became almost zero after heating at 950 degrees C. Addition of fly ash did not show any improvement in strength, durability and leachability of metals from the thermally treated product. X-ray diffraction (XRD) analysis of the product confirmed the presence of mixed phases of oxides of toxic metals.

Report: transboundary hazardous waste management. part II: performance auditing of treatment facilities in importing countries.

PubMed

Chang, Tien-Chin; Ni, Shih-Piao; Fan, Kuo-Shuh; Lee, Ching-Hwa

2006-06-01

Before implementing the self-monitoring model programme of the Basel Convention in the Asia, Taiwan has conducted a comprehensive 4-year follow-up project to visit the governmental authorities and waste-disposal facilities in the countries that import waste from Taiwan. A total of nine treatment facilities, six of which are reported in this paper, and the five countries where the plants are located were visited in 2001-2002. France, Belgium and Finland primarily handled polychlorinated biphenyl capacitors, steel mill dust and metal waste. The United States accepted metal sludge, mainly electroplating sludge, from Taiwan. Waste printed circuit boards, waste wires and cables, and a mixture of waste metals and electronics were the major items exported to China. Relatively speaking, most treatment plants for hazardous waste paid close attention to environmental management, such as pollution control and monitoring, site zoning, system management regarding occupational safety and hygiene, data management, permits application, and image promotion. Under the tight restrictions formulated by the central environment agency, waste treatment plants in China managed the environmental issues seriously. For example, one of the treatment plants had ISO 14001 certification. It is believed that with continuous implementation of regulations, more improvement is foreseeable. Meanwhile, Taiwan and China should also continuously enhance their collaboration regarding the transboundary management of hazardous waste.

Secondary Waste Cast Stone Waste Form Qualification Testing Plan

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

Westsik, Joseph H.; Serne, R. Jeffrey

2012-09-26

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). Cast Stone – a cementitious waste form, has been selected for solidification of this secondary waste stream after treatment in the ETF. The secondary-waste Cast Stone waste form must be acceptablemore » for disposal in the IDF. This secondary waste Cast Stone waste form qualification testing plan outlines the testing of the waste form and immobilization process to demonstrate that the Cast Stone waste form can comply with the disposal requirements. Specifications for the secondary-waste Cast Stone waste form have not been established. For this testing plan, Cast Stone specifications are derived from specifications for the immobilized LAW glass in the WTP contract, the waste acceptance criteria for the IDF, and the waste acceptance criteria in the IDF Permit issued by the State of Washington. This testing plan outlines the testing needed to demonstrate that the waste form can comply with these waste form specifications and acceptance criteria. The testing program must also demonstrate that the immobilization process can be controlled to consistently provide an acceptable waste form product. This testing plan also outlines the testing needed to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support performance assessment analyses of the long-term environmental impact of the secondary-waste Cast Stone waste form in the IDF« less

Method of treating waste water

DOEpatents

Deininger, James P.; Chatfield, Linda K.

1995-01-01

A process of treating water to remove metal ion contaminants contained therein, said metal ion contaminants selected from the group consisting of metals in Groups 8, 1b, 2b, 4a, 5a, or 6a of the periodic table, lanthanide metals, and actinide metals including transuranic element metals, by adjusting the pH of a metal ion contaminant-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with a mixture of an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, in an amount sufficient to form a precipitate within the water source, the amount the mixture of ferrate and water soluble salt effective to reduce the metal ion contaminant concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced metal ion contaminant concentration, and separating the supernatant liquid having the reduced metal ion contaminant concentration from the admixture is provided. A composition of matter including an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, is also provided.

Novel waste printed circuit board recycling process with molten salt.

PubMed

Riedewald, Frank; Sousa-Gallagher, Maria

2015-01-01

The objective of the method was to prove the concept of a novel waste PCBs recycling process which uses inert, stable molten salts as the direct heat transfer fluid and, simultaneously, uses this molten salt to separate the metal products in either liquid (solder, zinc, tin, lead, etc.) or solid (copper, gold, steel, palladium, etc.) form at the operating temperatures of 450-470 °C. The PCB recovery reactor is essentially a U-shaped reactor with the molten salt providing a continuous fluid, allowing molten salt access from different depths for metal recovery. A laboratory scale batch reactor was constructed using 316L as suitable construction material. For safety reasons, the inert, stable LiCl-KCl molten salts were used as direct heat transfer fluid. Recovered materials were washed with hot water to remove residual salt before metal recovery assessment. The impact of this work was to show metal separation using molten salts in one single unit, by using this novel reactor methodology. •The reactor is a U-shaped reactor filled with a continuous liquid with a sloped bottom representing a novel reactor concept.•This method uses large PCB pieces instead of shredded PCBs as the reactor volume is 2.2 L.•The treated PCBs can be removed via leg B while the process is on-going.

A comparative study of sorption of chromium (III) onto chitin and chitosan

NASA Astrophysics Data System (ADS)

Singh, Pooja; Nagendran, R.

2016-06-01

Heavy metals have always been the most hazardous components in the wastewater of industries like electroplating, automobiles, mining facilities and fertilizer manufacturers. Treatment of heavy metal laden wastewater requires expensive operational and maintenance systems. Food processing industries create a huge amount of shell waste which is sold to poultry farms in powdered form but the quantity thus used is still not comparable to the left over waste. The shell contains chitin which acts as an adsorbent for the heavy metals and can be used to treat heavy metal wastewater. The paper presents a study on the use of chitin and its processed product, chitosan, to remove chromium. Shake flask experiment was conducted to compare the adsorptive capacity of chitin and chitosan for chromium removal from simulated solution and isotherm studies were carried out. The studies showed that the chitosan was a better adsorbent than chitin. Both chitin and chitosan gave best adsorption results at pH 3. Chitin exhibited maximum chromium removal of 49.98 % in 20 min, whereas chitosan showed 50 % removal efficiency at a contact time of 20 min showing higher adsorptive capacity for chromium than chitin. The Langmiur and Freundlich isotherm studies showed very good adsorption capacity and monolayer interaction according to the regression coefficient 0.973 for chitosan and 0.915 for chitin. The regression coefficient for Freundlich isotherm was 0.894 and 0.831 for chitosan and chitin, respectively.

Novel waste printed circuit board recycling process with molten salt

PubMed Central

Riedewald, Frank; Sousa-Gallagher, Maria

2015-01-01

The objective of the method was to prove the concept of a novel waste PCBs recycling process which uses inert, stable molten salts as the direct heat transfer fluid and, simultaneously, uses this molten salt to separate the metal products in either liquid (solder, zinc, tin, lead, etc.) or solid (copper, gold, steel, palladium, etc.) form at the operating temperatures of 450–470 °C. The PCB recovery reactor is essentially a U-shaped reactor with the molten salt providing a continuous fluid, allowing molten salt access from different depths for metal recovery. A laboratory scale batch reactor was constructed using 316L as suitable construction material. For safety reasons, the inert, stable LiCl–KCl molten salts were used as direct heat transfer fluid. Recovered materials were washed with hot water to remove residual salt before metal recovery assessment. The impact of this work was to show metal separation using molten salts in one single unit, by using this novel reactor methodology. • The reactor is a U-shaped reactor filled with a continuous liquid with a sloped bottom representing a novel reactor concept. • This method uses large PCB pieces instead of shredded PCBs as the reactor volume is 2.2 L. • The treated PCBs can be removed via leg B while the process is on-going. PMID:26150977

Distribution of metals and brominated flame retardants (BFRs) in sediments, soils and plants from an informal e-waste dismantling site, South China.

PubMed

Wang, Junxia; Liu, Lili; Wang, Jinfu; Pan, Bishu; Fu, Xiaoxu; Zhang, Gang; Zhang, Long; Lin, Kuangfei

2015-01-01

Brominated flame retardants (BFRs, including polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol-A (TBBPA)) and metals (Cu, Zn, Pb, Cd, Ni, Hg and As) in sediments, soils and herb plants from unregulated e-waste disposal sites were examined. The metal concentrations, ∑PBDE and TBBPA concentrations in all samples from the examined e-waste dismantling sites were relatively high in comparison with those of rural and urban areas around the world. The PBDE and TBBPA levels in soils significantly decreased with increasing distance from the e-waste dismantling sites, indicating that PBDEs and TBBPA had similar transport potential from the e-waste dismantling process as a point source to the surrounding region. BDE-209 and TBBPA predominated in all samples, which is consistent with the evidence that the deca-BDE and TBBPA commercial mixtures were extensively used in electronic products. Metals, PBDEs and TBBPA displayed significant positive correlations with TOC, whereas the correlations with pH were insignificant, indicating that TOC was a major factor governing the spatial distribution, transportation and fate in sediments and soils. A significant relationship between log-transformed metals and BFR concentrations indicated common pollution sources. Moreover, cluster analysis and principal component analysis further confirmed that the metals and BFRs had a common source, and penta- and deca-BDE commercial products may be two sources of PBDEs in this region.

Carbon-Carbon Bond Formation and Hydrogen Production in the Ketonization of Aldehydes.

PubMed

Orozco, Lina M; Renz, Michael; Corma, Avelino

2016-09-08

Aldehydes possess relatively high chemical energy, which is the driving force for disproportionation reactions such as Cannizzaro and Tishchenko reactions. Generally, this energy is wasted if aldehydes are transformed into carboxylic acids with a sacrificial oxidant. Here, we describe a cascade reaction in which the surplus energy of the transformation is liberated as molecular hydrogen for the oxidation of heptanal to heptanoic acid by water, and the carboxylic acid is transformed into potentially industrially relevant symmetrical ketones by ketonic decarboxylation. The cascade reaction is catalyzed by monoclinic zirconium oxide (m-ZrO2 ). The reaction mechanism has been studied through cross-coupling experiments between different aldehydes and acids, and the final symmetrical ketones are formed by a reaction pathway that involves the previously formed carboxylic acids. Isotopic studies indicate that the carboxylic acid can be formed by a hydride shift from the adsorbed aldehyde on the metal oxide surface in the absence of noble metals. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lignor process for acidic rock drainage treatment.

PubMed

Zhuang, J M; Walsh, T

2004-09-01

The process using lignosulfonates for acidic rock drainage (ARD) treatment is referred to as the Lignor process. Lignosulfonates are waste by-products produced in the sulfite pulping process. The present study has shown lignosulfonates are able to protect lime from developing an external surface coating, and hence to favor its dissociation. Further, the addition of lignosulfonates to ARD solutions increased the dotting and settling rate of the formed sludge. The capability of lignosulfonates to form stable metal-lignin complexes makes them very useful in retaining metal ions and thus improving the long-term stability of the sludge against leaching. The Lignor process involves metal sorption with lignosulfonates, ARD neutralization by lime to about pH 7, pH adjustment with caustic soda to 9.4 - 9.6, air oxidation to lower the pH to a desired level, and addition of a minimum amount of FeCl3 for further removal of dissolved metals. The Lignor process removes all concerned metals (especially Al and Mn) from the ARD of the Britannia Mine (located at Britannia Beach, British Columbia, Canada) to a level lower than the limits of the B.C. Regulations. Compared with the high-density sludge (HDS) process, the Lignor process has many advantages, such as considerable savings in lime consumption, greatly reduced sludge volume, and improved sludge stability.

Evaluation of the public health risks associated with semivolatile metal and dioxin emissions from hazardous waste incinerators.

PubMed Central

Sedman, R M; Esparza, J R

1991-01-01

The public health impacts associated with stack emissions from hazardous waste incinerators have become a major concern in recent years. Most evaluations of incinerator stack emissions have focused on three classes of compounds: metals, semivolatile, and volatile compounds. These investigations have been complicated by the difficulty and expense of analyzing the emissions and the limited amount of toxicity information for many of the compounds that have been detected. The results of over 20 trial burns at hazardous waste incinerators were assembled in an attempt to determine which compounds may pose a significant threat to the public health. The risks associated with semivolatile emissions were found to be inconsequential, although further study of dioxins and dibenzofurans emissions appears to be warranted. The risk associated with the emission of cadmium and perhaps chromium (VI) may pose a significant risk to public health at certain facilities. Controls on waste feed or air pollution control devices should be employed to reduce the emission of these metals. Any monitoring of metal emissions from hazardous waste incinerators should focus on cadmium and chromium (VI). PMID:1954929

Fractionation study in bioleached metallurgy wastes using six-step sequential extraction.

PubMed

Krasnodebska-Ostrega, Beata; Pałdyna, Joanna; Kowalska, Joanna; Jedynak, Łukasz; Golimowski, Jerzy

2009-08-15

The stored metallurgy wastes contain residues from ore processing operations that are characterized by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria. In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland (Szklary). Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied. Analyses of the extracts were performed by ICP-MS and FAAS. To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. 80-100% of total metal concentrations were mobilized after the proposed treatment. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.

Metals and polybrominated diphenyl ethers leaching from electronic waste in simulated landfills.

PubMed

Kiddee, Peeranart; Naidu, Ravi; Wong, Ming H

2013-05-15

Landfills established prior to the recognition of potential impacts from the leaching of heavy metals and toxic organic compounds often lack appropriate barriers and pose significant risks of contamination of groundwater. In this study, bioavailable metal(oids) and polybrominated diphenyl ethers (PBDEs) in leachates from landfill columns that contained intact or broken e-waste were studied under conditions that simulate landfills in terms of waste components and methods of disposal of e-wastes, and with realistic rainfall. Fourteen elements and PBDEs were analysed in leachates over a period of 21 months. The results demonstrate that the average concentrations of Al, Ba, Be, Cd, Co, Cr, Cu, Ni, Pb, Sb and V in leachates from the column that contained broken e-waste items were significantly higher than the column without e-waste. BDE-153 was the highest average PBDEs congener in all columns but the average of ∑PBDEs levels in columns that contained intact e-waste were (3.7 ng/l) and were not significantly higher than that in the leachates from the control column. Copyright © 2013 Elsevier B.V. All rights reserved.

Trace-metal sources and their release from mine wastes: examples from humidity cell tests of hardrock mine waste and from Warrior Basin coal

USGS Publications Warehouse

Diehl, S.F.; Smith, Kathleen S.; Desborough, G.A.; White, W.W.; Lapakko, K.A.; Goldhaber, Martin B.; Fey, David L.

2003-01-01

To assess the potential impact of metal and acid contamination from mine-waste piles, it is important to identify the mineralogic source of trace metals and their mode of occurrence. Microscopic analysis of mine-waste samples from both hard-rock and coalmine waste samples demonstrate a microstructural control, as well as mineralogic control, on the source and release of trace metals into local water systems. The samples discussed herein show multiple periods of sulfide mineralization with varying concentrations of trace metals. In the first case study, two proprietary hard-rock mine-waste samples exposed to a series of humidity cell tests (which simulate intense chemical weathering conditions) generated acid and released trace metals. Some trace elements of interest were: arsenic (45-120 ppm), copper (60-320 ppm), and zinc (30-2,500 ppm). Untested and humidity cell-exposed samples were studied by X-ray diffraction, scanning electron microscope with energy dispersive X-ray (SEM/EDX), and electron microprobe analysis. Studies of one sample set revealed arsenic-bearing pyrite in early iron- and magnesium-rich carbonate-filled microveins, and iron-, copper-, arsenic-, antimony-bearing sulfides in later crosscutting silica-filled microveins. Post humidity cell tests indicated that the carbonate minerals were removed by leaching in the humidity cells, exposing pyrite to oxidative conditions. However, sulfides in the silica-filled veins were more protected. Therefore, the trace metals contained in the sulfides within the silica-filled microveins may be released to the surface and (or) ground water system more slowly over a greater time period. In the second case study, trace metal-rich pyrite-bearing coals from the Warrior Basin, Alabama were analyzed. Arsenic-bearing pyrite was observed in a late-stage pyrite phase in microfaults and microveins that crosscut earlier arsenic.

Update Direct-Strike Lightning Environment for Stockpile-to-Target Sequence: Supplement LLNL Subcontract #B568621 Lightning Protection at the Yucca Mountain Waste Storage Facility

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

Uman, M A

2008-10-09

The University of Florida has surveyed all relevant publications reporting lightning damage to metals, metals which could be used as components of storage containers for nuclear waste materials. We show that even the most severe lightning could not penetrate the stainless steel thicknesses proposed for nuclear waste storage casks.

Effects of moisture content and initial pH in composting process on heavy metal removal characteristics of grass clipping compost used for stormwater filtration.

PubMed

Khan, Eakalak; Khaodhir, Sutha; Ruangrote, Darin

2009-10-01

Heavy metals are common contaminants in stormwater runoff. One of the devices that can be used to effectively and economically remove heavy metals from runoff is a yard waste compost stormwater filter. The primary goal of composting is to reduce waste volume rather than to produce stormwater filter media. Moisture content (MC) and initial pH, the two important parameters in composting, were studied for their effects on yard waste volume reduction and heavy metal adsorption performances of the compost. The main objective of this investigation was to examine whether the conditions that provided high yard waste volume reduction would also result in compost with good heavy metal removal performances. Manila grass was composted at different initial pHs (5-9) and MCs (30-70%) and the composts were used to adsorb cadmium, copper, lead and zinc from water. Results indicated that MC is more critical than initial pH for both volume reduction and production of compost with high metal adsorption performances. The most optimal conditions for the two attributes were not exactly the same but lower MCs of 30-40% and pH 7 or higher tended to satisfy both high volume reduction and effective metal adsorption.

Comprehensive process for the recovery of value and critical materials from electronic waste

DOE PAGES

Diaz, Luis A.; Lister, Tedd E.; Parkman, Jacob A.; ...

2016-04-08

The development of technologies that contribute to the proper disposal and treatment of electronic waste is not just an environmental need, but an opportunity for the recovery and recycle of valuable metals and critical materials. Value elements in electronic waste include gold, palladium, silver, copper, nickel, and rare earth elements (RE). Here, we present the development of a process that enables efficient recycling of metals from scrap mobile electronics. An electro recycling (ER) process, based on the regeneration of Fe 3+ as a weak oxidizer, is studied for the selective recovery of base metals while leaving precious metals for separatemore » extraction at reduced chemical demand. A separate process recovers rare earth oxides from magnets in electronics. Furthermore, recovery and extraction efficiencies ca. 90 % were obtained for the extraction of base metals from the non-ferromagnetic fraction in the two different solution matrices tested (H 2SO 4, and HCl). The effect of the pre-extraction of base metals in the increase of precious metals extraction efficiency was verified. On the other hand, the extraction of rare earths from the ferromagnetic fraction, performed by means of anaerobic extraction in acid media, was assessed for the selective recovery of rare earths. We developed a comprehensive flow sheet to process electronic waste to value products.« less

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Prohibitions on Land Disposal § 268.34 Waste... wastes are prohibited from land disposal: the wastes specified in 40 CFR Part 261 as EPA Hazardous Waste... 261. (b) Effective November 26, 1998, the following waste is prohibited from land disposal: Slag from...

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Prohibitions on Land Disposal § 268.34 Waste... wastes are prohibited from land disposal: the wastes specified in 40 CFR Part 261 as EPA Hazardous Waste... 261. (b) Effective November 26, 1998, the following waste is prohibited from land disposal: Slag from...

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Prohibitions on Land Disposal § 268.34 Waste... wastes are prohibited from land disposal: the wastes specified in 40 CFR Part 261 as EPA Hazardous Waste... 261. (b) Effective November 26, 1998, the following waste is prohibited from land disposal: Slag from...

40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2012 CFR

2012-07-01

... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment..., acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals... oxygen. (d) For approval, a State plan shall include emission limits for nitrogen oxides at least as...

40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2013 CFR

2013-07-01

... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment..., acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals... oxygen. (d) For approval, a State plan shall include emission limits for nitrogen oxides at least as...

40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2011 CFR

2011-07-01

... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment..., acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals... oxygen. (d) For approval, a State plan shall include emission limits for nitrogen oxides at least as...

40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

Code of Federal Regulations, 2014 CFR

2014-07-01

... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment..., acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals... oxygen. (d) For approval, a State plan shall include emission limits for nitrogen oxides at least as...

State of the Science Review: Potential for Beneficial Use of Waste By-Products for In-situ Remediation of Metal-Contaminated Soil and Sediment

EPA Science Inventory

Metal and metalloid contamination of soil and sediment is a widespread problem both in urban and rural areas throughout the United States (U.S. EPA, 2014). Beneficial use of waste by-products as amendments to remediate metal-contaminated soils and sediments can provide major eco...

Perspectives regarding the use of metallurgical slags as secondary metal resources - A review of bioleaching approaches.

PubMed

Potysz, Anna; van Hullebusch, Eric D; Kierczak, Jakub

2018-05-05

Smelting activity by its very nature produces large amounts of metal-bearing waste, often called metallurgical slag(s). In the past, industry used to dispose of these waste products at dumping sites without the appropriate environmental oversight. Once there, ongoing biogeochemical processes affect the stability of the slags and cause the release of metallic contaminants. Rather than viewing metallurgical slags as waste, however, such deposits should be viewed as secondary metal resources. Metal bioleaching is a "green" treatment route for metallurgical slags, currently being studied under laboratory conditions. Metal-laden leachates obtained at the bioleaching stage have to be subjected to further recovery operations in order to obtain metal(s) of interest to achieve the highest levels of purity possible. This perspective paper considers the feasibility of the reuse of base-metal slags as secondary metal resources. Special focus is given to current laboratory bioleaching approaches and associated processing obstacles. Further directions of research for development of more efficient methods for waste slag treatment are also highlighted. The optimized procedure for slag treatment is defined as the result of this review and should include following steps: i) slag characterization (chemical and phase composition and buffering capacity) following the choice of initial pH, ii) the choice of particle size, iii) the choice of the liquid-to-solid ratio, iv) the choice of microorganisms, v) the choice of optimal nutrient supply (growth medium composition). An optimal combination of all these parameters will lead to efficient extraction and generation of metal-free solid residue. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sorption of copper(II) from aqueous phase by waste biomass

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

Nagendra Rao, C.R.; Iyengar, L.; Venkobachar, C.

The objective of the present investigation is to compare three biomasses for copper uptake under different experimental conditions so as to choose the most suitable one for scaleup purposes. Ganoderma lucidum is a macrofungi, growing widely in tropical forests. Sorbent preparation requires its collection from the field. Asperigillus niger is obtained as a waste biomass from the fermentation industry. Activated sludge biomass is available from the biological waste treatment plants. The results of their potential to remove copper are presented. The copper uptake by biosorbents though, varied significantly, showed an increased trend in the range of pH 4 to 6.more » The increase in metal binding after alkali treatment was marginal for G. lucidum, significant for A. niger, and dramatic for sludge. Copper sorption capacities of M and M[sub c] were much higher than for other sorbents at pH 5.0. The effect of anionic ligands, like acetate and tartrate on copper uptake by raw and alkali treated biosorbents, was negligible as the predominant species in the presence of these ligands is divalent copper ion. Pyrophosphate, citrate, and EDTA had varying degrees of adverse effects on metal uptake. Thus, among the sorbents G. lucidum in its raw form is best suited for the practical application of copper removal from industrial effluents.« less

The impact of incinerators on human health and environment.

PubMed

Sharma, Raman; Sharma, Meenakshi; Sharma, Ratika; Sharma, Vivek

2013-01-01

Of the total wastes generated by health-care organizations, 10%-25% are biomedical wastes, which are hazardous to humans and the environment and requires specific treatment and management. For decades, incineration was the method of choice for the treatment of such infectious wastes. Incinerator releases a wide variety of pollutants depending on the composition of the waste, which leads to health deterioration and environmental degradation. The significant pollutants emitted are particulate matter, metals, acid gases, oxides of nitrogen, and sulfur, aside from the release of innumerable substances of unknown toxicity. This process of waste incineration poses a significant threat to public health and the environment. The major impact on health is the higher incidence of cancer and respiratory symptoms; other potential effects are congenital abnormalities, hormonal defects, and increase in sex ratio. The effect on the environmental is in the form of global warming, acidification, photochemical ozone or smog formation, eutrophication, and human and animal toxicity. Thus, there is a need to skip to newer, widely accepted, economical, and environment-friendly technologies. The use of hydroclaves and plasma pyrolysis for the incineration of biomedical wastes leads to lesser environmental degradation, negligible health impacts, safe handling of treated wastes, lesser running and maintenance costs, more effective reduction of microorganisms, and safer disposal.

Prevention of sulfide oxidation in sulfide-rich waste rock

NASA Astrophysics Data System (ADS)

Nyström, Elsa; Alakangas, Lena

2015-04-01

The ability to reduce sulfide oxidation in waste rock after mine closure is a widely researched area, but to reduce and/or inhibit the oxidation during operation is less common. Sulfide-rich (ca 30 % sulfur) waste rock, partially oxidized, was leached during unsaturated laboratory condition. Trace elements such as As and Sb were relatively high in the waste rock while other sulfide-associated elements such as Cu, Pb and Zn were low compared to common sulfide-rich waste rock. Leaching of unsaturated waste rock lowered the pH, from around six down to two, resulting in continuously increasing element concentrations during the leaching period of 272 days. The concentrations of As (65 mg/L), Cu (6.9 mg/L), Sb (1.2 mg/L), Zn (149 mg/L) and S (43 g/L) were strongly elevated at the end of the leaching period. Different alkaline industrial residues such as slag, lime kiln dust and cement kiln dust were added as solid or as liquid to the waste rock in an attempt to inhibit sulfide oxidation through neo-formed phases on sulfide surfaces in order to decrease the mobility of metals and metalloids over longer time scale. This will result in a lower cost and efforts of measures after mine closure. Results from the experiments will be presented.

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

DOE PAGES

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

2017-08-30

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

Physico-chemical treatment of liquid waste on an industrial plant for electrocoagulation.

PubMed

Mlakar, Matej; Levstek, Marjetka; Stražar, Marjeta

2017-10-01

Wastewater from washing, oil separators, the metal processing and detergent industries, was tested and treated for treatment of different types of liquid waste at industrial level at Domžale-Kamnik Wastewater Treatment Plant (WWTP). The effect of implementing the electrocoagulation (EC) and flotation processes, respectively, is analysed and includes the duration of the EC implementation, voltage, number of electrodes, and chemical addition, as well as the pH effect and conductivity. The tests were performed not only on various types of liquid waste, but also on different mixtures of liquid waste. Laboratory analysis of the samples before and after EC have shown an effective reduction not only in organic loads in accordance with the COD (chemical oxygen demand) parameter, but also in mineral oil content, toxic metal concentration, and surfactants. The COD in liquid waste from the detergent industry was reduced by 73% and the content of surfactants by 64%. In liquid waste from the metal processing industry, the COD decreased by up to 95%, while the content of toxic metals decreased from 59 to 99%. Similar phenomena were shown in liquid waste from oil separators, where the COD was reduced to 33% and the concentration of mineral oils by 99%. Some of the liquid wastes were mixed together in the ratio 1:1, thus allowing testing of the operation of EC technology in heterogeneous liquid waste, where the final result proved to be effective cleaning as well. After treatment in the process of EC, the limit values of the treated water proved appropriate for discharge into the sewerage system.

In situ distributions and characteristics of heavy metals in full-scale landfill layers.

PubMed

He, Pin-Jing; Xiao, Zheng; Shao, Li-Ming; Yu, Ji-Yu; Lee, Duu-Jong

2006-10-11

The leachate from methanogenic landfill normally contains low concentrations of heavy metals. Little samples had ever been collected from the full-scale landfill piles owing to technical difficulty for well drilling. We drilled two wells in Hangzhou Tianziling landfill, 20 m and 32 m in depth each, and collected solid samples of waste age of 1-4 years from both wells. The total amounts, the sequentially extracted amounts, and the chemical binding forms of heavy metals of the samples collected at different depths were measured. With the correlation between leachate production amount and the yearly rainfall amount, the leached ratio of the heavy metals were estimated only 0.13%, 1.8%, 0.15%, and 0.19% of Cu, Cd, Pb, and Zn, respectively. The heavy metals amounts in the main compositions of MSW, like glass, food waste, paper, coal cinders, were measured using fresh MSW samples. Afterward, the contents of heavy metals initially landfilled were estimated. A positive correlation was noted between the measured and the estimated initial contents of heavy metals, indicating that the low migration of heavy metals in landfill layers. However, among the metals investigated, Zn has shown better mobility inside landfill layers. Acid volatile sulfide (AVS) and the simultaneously extracted metals (SEM) were measured for all collected samples with optimal reaction conditions identified to yield nearly perfect sulfide recovery as follows: 100 g wet samples, 80 mL min(-1) N(2) flow rate, reaction time of 150 min. The SEM/AVS ratios ranged 25-45, indicating that the AVS was insufficient to immobilize the SEM. Sequential extraction using six-fraction scheme revealed that the sum of exchangeable and the avid soluble fractions of heavy metals follow: Zn>Cd>Cu, Ni, Pb>Cr. The insoluble fraction of heavy metals in MSW was high, for instance, over 80% for Cr and Pb high insoluble fractions of heavy metals in the landfilled MSW and the sorption capability of the methanogenic landfill layers should be responsible to the low concentrations of heavy metals found in leachate.

Removal of copper from aqueous solution using perlite

NASA Astrophysics Data System (ADS)

Tanaydin, Mehmet Kayra; Tanaydin, Zümra Bakici; Ince, Muharrem; Demırkiran, Nizamettin

2017-04-01

The wastewaters containing organic and inorganic pollutants after many industrial processes such as metal plating, mining, textile, alloy, battery and industrial chemicals, are often discharged to environment. Heavy metals among these pollutants have highly stable, toxic, non-degradable and carcinogenic characters. They affect not only ecological system, but also human health and many life forms. Therefore, these contaminants should be eliminated or reduced to allowable levels before releasing to environment. Most of heavy metals have toxic character even at low concentrations of about 0.1-0.3 ppm. Treatment technologies such as filtration, ion exchange, precipitation, electrodeposition, reverse osmosis, sedimentation, and adsorption have been applied for removal of heavy metals from aqueous solutions. Adsorption is one of the most common and widely applied methods to eliminate the metal ions from waste solutions because of its simplicity and cost effectiveness. Activated carbon, clay minerals, ion exchange resins and various agricultural residues can be used as adsorbent materials in this process [1-3].