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Said Jalali - One of the best experts on this subject based on the ideXlab platform.
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Investigations of tungsten mine Waste geopolymeric binder: Strength and microstructure
Construction and Building Materials, 2008Co-Authors: Fernando Pacheco-torgal, João Castro-gomes, Said JalaliAbstract:Abstract This paper reports some results of a research project related to the development of a new binder using Mineral Waste mud from the Portuguese mine. Some aspects related to the effect of aggregates in the microstructure and mechanical behaviour of tungsten mine Waste geopolymeric binder are reported in the present study. Test results showed that the aggregate type influences strength development.
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Tungsten mine Waste geopolymeric binder versus ordinary portland cement based concrete : abrasion and acid resistance
2007Co-Authors: Fernando Pacheco Torgal, J. P. Castro Gomes, Said JalaliAbstract:This paper reports results of a research project related to the development of geopolymeric binder using Mineral Waste mud from the Portuguese tungsten mine Panasqueira. Abrasion and acid resistance of two ordinary Portland cement (OPC) strength class concrete mixtures (C20/25 and C30/37) and several tungsten mine Waste mud (TMWM) geopolymeric binder mixtures was evaluated. Acid resistance was performed by submitting samples to solutions of sulphuric acid, nitric acid and chloridric acid, results of weight loss are reported. Abrasion resistance was assessed by the mass loss of cubic specimens when submitted to 1000 rotations with the Los Angeles apparatus test machine. This study indicates that TMWM geopolymeric binders possess higher acid and abrasion resistance than OPC based concrete mixtures.
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alkali activated geopolymeric binder using tungesten mine Waste preliminary investigation
2005Co-Authors: Fernando Pacheco Torgal, J Castro P Gomes, Said JalaliAbstract:This paper reports preliminary results of a PhD research project related to the development of an alkaliactivated geopolymeric binder using Mineral Waste mud from the Portuguese tungsten mine Panasqueira which is still operating. Mineralogical analysis indicates that the Waste mud is compose mainly of muscovite and quartz with a high content of iron and alkali metals. Results of the dehydroxylation process are presented by x-ray diffraction and infrared emission spectroscopy patterns of quenched Waste powder and also from compressive strength of alkali-activated mortar specimens, showing a significant potential as a geopolymeric source precursor. Considerations about Portuguese industrial Waste production are made showing a high level ratio of CO2 emissions mostly from cement industry, a nation-wide lack of fly ash and blast furnace slag to be used as cementitious by-products and huge amounts of quarrying and mining Wastes and also the need to preserve it`s large and protected natural areas leading to the use of alumino-silicate Minerals as the only reasonable alternative to the development of alkali-activated friendly environmental binders. Materials raw cost comparisons between Portland cement based concretes and alkali-activated geopolymeric based concretes are also made showing that Portland cement based ones are by far the most economic ones but not for very long due to the expected increase in Portland cement cost under the recent implementation of CO2 emissions trading scheme (ETS).
Cristina Nerín - One of the best experts on this subject based on the ideXlab platform.
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Co-pyrolysis of a Mineral Waste oil/coal slurry in a continuous-mode fluidized bed reactor
Journal of Analytical and Applied Pyrolysis, 2002Co-Authors: María Jesús Lázaro, Celia Domeño, R. Moliner, Isabel Suelves, Cristina NerínAbstract:Abstract The main objective of this paper is to study the co-pyrolysis of a Spanish low rank coal and a Mineral Waste oil (MWO) slurry. The goal is to process the coal, handling it as a slurry by using a Waste as the fluid component of the slurry in a continuous-mode preparative scale pyrolysis unit. It has been shown that a MWO/coal slurry can be successfully processed in a pulsed feeding fluidized bed reactor. Liquid and gases fractions have been analysed for organic products and metals. High yields of valuable light olefins such as ethylene and propylene and light aromatics as benzene, toluene, xylene and naphthalene derivatives have been obtained. The results show that both quantity and quality of gases and liquids obtained are significantly improved in relation to those obtained from coal. Special attention has been paid to the fate of metals contained in the MWO/coal slurries and their distribution into the co-pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that metals under study are totally or partially trapped in the char formed during co-pyrolysis. This way the contents of Pb, Cu, V and Ni in the pyrolysis products leaving the reactor is substantially lower than in the feeding what will facilitate the obtention of valuable products.
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Valuable Products from Mineral Waste Oils Containing Heavy Metals
Environmental Science & Technology, 2000Co-Authors: María Jesús Lázaro, Cristina Nerín, R. Moliner, Isabel Suelves, Celia DomeñoAbstract:The main objective of this paper is to study the conversion of Mineral Waste oils (MWO) containing heavy metals into valuable products via pyrolysis. The pyrolysis of the MWO has been carried out in a continuous-mode preparative scale pyrolysis unit containing a bed of char obtained from the Samca coal, a low-rank coal. Temperature of 625 °C and 700 °C and pressures of 0.1 and 1 MPa have been used. High yields of valuable light olefins as ethylene and propylene and light aromatics as BTX and naphthalene derivatives have been obtained. Special attention has been paid to the fate of the metals contained in the MWO during pyrolysis and their distribution into the pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that the Samca coal chars used has the ability to take up some of the metals under study, but the behavior of each metal is different. So, while Pb and Cu are mostly retained in the coal char bed, V is not affected, and Cd, Ni, a...
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Determination of PCBs in some Mineral Waste oils
Toxicological & Environmental Chemistry, 1996Co-Authors: Cristina Nerín, Celia Domeño, I. Echarri, A. R. TornésAbstract:Different clean‐up procedures for PCB analysis are compared. Sulphuric acid‐silica gel column was the most effective clean‐up procedure to determine PCBs in Mineral Waste oils.
Stephen Hillier - One of the best experts on this subject based on the ideXlab platform.
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Use of hydraulic binders for reducing sulphate leaching: application to gypsiferous soil sampled in Ile-de-France region (France)
Environmental Science and Pollution Research, 2018Co-Authors: Vincent Trincal, Vincent Thiéry, Yannick Mamindy-pajany, Stephen HillierAbstract:Polluted soils are a serious environmental risk worldwide and consist of millions of tons of Mineral Waste to be treated. In order to ensure their sustainable management, various remediation options must be considered. Hydraulic binder treatment is one option that may allow a stabilisation of pollution and thus offer a valorisation as secondary raw materials rather than considering them as Waste. In this study, we focused on sulphate-polluted soil and tested the effectiveness of several experimental hydraulic binders. The aim was to transform gypsum into ettringite, a much less soluble sulphate, and therefore to restrict the potential for sulphate pollutant release. The environmental assessment of five formulations using hydraulic binders was compared to the gypsiferous soil before treatment (contaminated in sulphate). The approach was to combine leaching tests with Mineralogical quantifications using among others thermogravimetric and XRD methods. In the original soil and in the five formulations, leaching tests indicate sulphate release above environmental standards. However, hydraulic binders promote ettringite formation, as well as a gypsum content reduction as observed by SEM. The stabilisation of sulphates is, however, insufficient, probably as a result of the very high content of gypsum in the unusual soil used. The Mineralogical reactions highlighted during the hydration of hydraulic binders are promising; they could pave the way for the development of new industrial mixtures that would have a positive environmental impact by allowing reuse of soils that would otherwise be classified as Waste.
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Use of hydraulic binders for reducing sulphate leaching: application to gypsiferous soil sampled in Ile-de-France region (France)
Environmental Science and Pollution Research, 2018Co-Authors: Vincent Trincal, Vincent Thiéry, Yannick Mamindy-pajany, Stephen HillierAbstract:Polluted soils are a serious environmental risk worldwide and consist of millions of tons of Mineral Waste to be treated. In order to ensure their sustainable management, various remediation options must be considered. Hydraulic binder treatment is one option that may allow a stabilisation of pollution and thus offer a valorisation as secondary raw materials rather than considering them as Waste. In this study, we focused on sulphate-polluted soil and tested the effectiveness of several experimental hydraulic binders. The aim was to transform gypsum into ettringite, a much less soluble sulphate, and therefore to restrict the potential for sulphate pollutant release. The environmental assessment of five formulations using hydraulic binders was compared to the gypsiferous soil before treatment (contaminated in sulphate). The approach was to combine leaching tests with Mineralogical quantifications using among others thermogravimetric and XRD methods. In the original soil and in the five formulations, leaching tests indicate sulphate release above environmental standards. However, hydraulic binders promote ettringite formation, as well as a gypsum content reduction as observed by SEM. The stabilisation of sulphates is, however, insufficient, probably as a result of the very high content of gypsum in the unusual soil used. The Mineralogical reactions highlighted during the hydration of hydraulic binders are promising; they could pave the way for the development of new industrial mixtures that would have a positive environmental impact by allowing reuse of soils that would otherwise be classified as Waste.
Carol M. Jantzen - One of the best experts on this subject based on the ideXlab platform.
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Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105 And AN-103) By Fluidized Bed Steam Reformation
2014Co-Authors: Carol M. Jantzen, Connie C. Herman, Charles L. Crawford, Christopher J. Bannochie, P Paul Burket, G Gene Daniel, A. D. Cozzi, Charles A. Nash, Donald H. Miller, D. M. MissimerAbstract:One of the immobilization technologies under consideration as a Supplemental Treatment for Hanford’s Low Activity Waste (LAW) is Fluidized Bed Steam Reforming (FBSR). The FBSR technology forms a Mineral Waste form at moderate processing temperatures thus retaining and atomically bonding the halides, sulfates, and technetium in the Mineral phases (nepheline, sodalite, nosean, carnegieite). Additions of kaolin clay are used instead of glass formers and the Minerals formed by the FBSR technology offers (1) atomic bonding of the radionuclides and constituents of concern (COC) comparable to glass, (2) short and long term durability comparable to glass, (3) disposal volumes comparable to glass, and (4) higher Na2O and SO{sub 4} Waste loadings than glass. The higher FBSR Na{sub 2}O and SO{sub 4} Waste loadings contribute to the low disposal volumes but also provide for more rapid processing of the LAW. Recent FBSR processing and testing of Hanford radioactive LAW (Tank SX-105 and AN-103) Waste is reported and compared to previous radioactive and non-radioactive LAW processing and testing.
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Radioactive Demonstration Of Mineralized Waste Forms Made From Hanford Low Activity Waste (Tank SX-105, Tank AN-103, And AZ-101/102) By Fluidized Bed Steam Reformation (FBSR)
2013Co-Authors: Carol M. Jantzen, Charles L. Crawford, Christopher J. Bannochie, P Paul Burket, A. D. Cozzi, Donald H. Miller, D. M. Missimer, William E. Daniel, H. K. Hall, Charles A. NashAbstract:Fluidized Bed Steam Reforming (FBSR) is a robust technology for the immobilization of a wide variety of radioactive Wastes. Applications have been tested at the pilot scale for the high sodium, sulfate, halide, organic and nitrate Wastes at the Hanford site, the Idaho National Laboratory (INL), and the Savannah River Site (SRS). Due to the moderate processing temperatures, halides, sulfates, and technetium are retained in Mineral phases of the feldspathoid family (nepheline, sodalite, nosean, carnegieite, etc). The feldspathoid Minerals bind the contaminants such as Tc-99 in cage (sodalite, nosean) or ring (nepheline) structures to surrounding aluminosilicate tetrahedra in the feldspathoid structures. The granular FBSR Mineral Waste form that is produced has a comparable durability to LAW glass based on the short term PCT testing in this study, the INL studies, SPFT and PUF testing from previous studies as given in the columns in Table 1-3 that represent the various durability tests. Monolithing of the granular product was shown to be feasible in a separate study. Macro-encapsulating the granular product provides a decrease in leaching compared to the FBSR granular product when the geopolymer is correctly formulated.
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Environmental Issues and Waste Management Technologies in the Ceramic and Nuclear Industries IX - Characterization and Performance of Fluidized Bed Steam Reforming (FBSR) Product as a Final Waste Form
Ceramic Transactions Series, 2012Co-Authors: Carol M. JantzenAbstract:A demonstration of Fluidized Bed Steam Reforming (FBSR) was recently completed on a Hanford Low Activity Waste (LAW) simulant. This technology produced stable Mineral phases (feldspathoids) when co-fired with clay. The Mineral phases are cage structured and were determined to retain anions as well as cations such as Re (simulant for Tc) in the Mineral cages. The FBSR Mineral Waste form exhibited incongruent leaching characteristics during Product Consistency Testing (PCT or ASTM C1285). FBSR Mineral Waste forms are EPA regulatory compliant at the Universal Treatment Standard (UTS) making delisting an attractive option for this Waste form.
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Fluidized Bed Steam Reformed (FBSR) Mineral Waste Forms: Characterization and Durability Testing
2007Co-Authors: Carol M. Jantzen, Troy H. Lorier, John M. Pareizs, James C. MarraAbstract:Fluidized Bed Steam Reforming (FBSR) is being considered as a Mineralizing technology for the immobilization of a wide variety of Wastes that are high in organics, nitrates-nitrites, halides, and/or sulfates. These Wastes include the decontaminated High Level Waste (HLW) supernates referred to as low activity Waste (LAW) at Department of Energy (DOE) sites in the United States and Waste streams that may be generated by the advanced nuclear fuel cycle flowsheets that are being considered by the Global Nuclear Energy Partnership (GNEP) initiative. The organics are pyrolyzed into CO{sub 2} and steam in the absence of air. The FBSR Mineral Waste form is a granular but can subsequently be made into a monolith for disposal if necessary. The Waste form is a multiphase Mineral assemblage of Na-Al-Si (NAS) feldspathoid Minerals (sodalite, nosean, and nepheline) with cage and ring structures that sequester radionuclides like Tc-99 and Cs-137 and anions such as SO{sub 4}, I, F, and Cl. Iron bearing spinel Minerals are also formed and these phases stabilize Resource Conservation and Recovery Act (RCRA) hazardous species such as Cr and Ni. Dissolution rates ({eta}) and activation energies of dissolution are parameters needed for Performance Assessments (PA) to be completed on themore » FBSR Mineral Waste form. These parameters are defined in this study by Single Pass Flow Through (SPFT) testing. The dissolution rate ({eta}) and the activation energies for dissolution calculated in this study agree with the available rate and activation energy data for natural single crystal nepheline. (authors)« less
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Fluidized Bed Steam Reformed Mineral Waste Forms: Characterization and Durability Testing
2006Co-Authors: Carol M. Jantzen, Troy H. Lorier, John M. Pareizs, James C. MarraAbstract:Fluidized Bed Steam Reforming (FBSR) is being considered as a potential technology for the immobilization of a wide variety of high sodium low activity Wastes (LAW) such as those existing at the Hanford site, at the Idaho National Laboratory (INL), and the Savannah River Site (SRS). The addition of clay, charcoal, and a catalyst as co-reactants with the Waste denitrates the aqueous Wastes and forms a granular Mineral Waste form that can subsequently be made into a monolith for disposal if necessary. The Waste form produced is a multiphase Mineral assemblage of Na-Al-Si (NAS) feldspathoid Minerals with cage and ring structures and iron bearing spinel Minerals. The Mineralization occurs at moderate temperatures between 650-750 C in the presence of superheated steam. The cage and ring structured feldspathoid Minerals atomically bond radionuclides like Tc-99 and Cs-137 and anions such as SO{sub 4}, I, F, and Cl. The spinel Minerals stabilize Resource Conservation and Recovery Act (RCRA) hazardous species such as Cr and Ni. Granular Mineral Waste forms were made from (1) a basic Hanford Envelope A low activity Waste (LAW) simulant and (2) an acidic INL simulant commonly referred to as sodium bearing Waste (SBW) in pilot scale facilities at the Science Applications International Corporation (SAIC) Science and Technology Applications Research (STAR) facility in Idaho Falls, ID. The FBSR Waste forms were characterized and the durability tested via ASTM C1285 (Product Consistency Test), the Environmental Protection Agency (EPA) Toxic Characteristic Leaching Procedure (TCLP), and the Single Pass Flow Through (SPFT) test. The results of the SPFT testing and the activation energies for dissolution are discussed in this study.
Celia Domeño - One of the best experts on this subject based on the ideXlab platform.
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Co-pyrolysis of a Mineral Waste oil/coal slurry in a continuous-mode fluidized bed reactor
Journal of Analytical and Applied Pyrolysis, 2002Co-Authors: María Jesús Lázaro, Celia Domeño, R. Moliner, Isabel Suelves, Cristina NerínAbstract:Abstract The main objective of this paper is to study the co-pyrolysis of a Spanish low rank coal and a Mineral Waste oil (MWO) slurry. The goal is to process the coal, handling it as a slurry by using a Waste as the fluid component of the slurry in a continuous-mode preparative scale pyrolysis unit. It has been shown that a MWO/coal slurry can be successfully processed in a pulsed feeding fluidized bed reactor. Liquid and gases fractions have been analysed for organic products and metals. High yields of valuable light olefins such as ethylene and propylene and light aromatics as benzene, toluene, xylene and naphthalene derivatives have been obtained. The results show that both quantity and quality of gases and liquids obtained are significantly improved in relation to those obtained from coal. Special attention has been paid to the fate of metals contained in the MWO/coal slurries and their distribution into the co-pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that metals under study are totally or partially trapped in the char formed during co-pyrolysis. This way the contents of Pb, Cu, V and Ni in the pyrolysis products leaving the reactor is substantially lower than in the feeding what will facilitate the obtention of valuable products.
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Valuable Products from Mineral Waste Oils Containing Heavy Metals
Environmental Science & Technology, 2000Co-Authors: María Jesús Lázaro, Cristina Nerín, R. Moliner, Isabel Suelves, Celia DomeñoAbstract:The main objective of this paper is to study the conversion of Mineral Waste oils (MWO) containing heavy metals into valuable products via pyrolysis. The pyrolysis of the MWO has been carried out in a continuous-mode preparative scale pyrolysis unit containing a bed of char obtained from the Samca coal, a low-rank coal. Temperature of 625 °C and 700 °C and pressures of 0.1 and 1 MPa have been used. High yields of valuable light olefins as ethylene and propylene and light aromatics as BTX and naphthalene derivatives have been obtained. Special attention has been paid to the fate of the metals contained in the MWO during pyrolysis and their distribution into the pyrolysis products. In particular, the distribution of six metals (Cd, Ni, Pb, Cu, Cr, V) has been studied. The data show that the Samca coal chars used has the ability to take up some of the metals under study, but the behavior of each metal is different. So, while Pb and Cu are mostly retained in the coal char bed, V is not affected, and Cd, Ni, a...
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Determination of PCBs in some Mineral Waste oils
Toxicological & Environmental Chemistry, 1996Co-Authors: Cristina Nerín, Celia Domeño, I. Echarri, A. R. TornésAbstract:Different clean‐up procedures for PCB analysis are compared. Sulphuric acid‐silica gel column was the most effective clean‐up procedure to determine PCBs in Mineral Waste oils.