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Roland Hischier - One of the best experts on this subject based on the ideXlab platform.

  • Waste Treatment and Assessment of Long-Term Emissions (8pp)
    The International Journal of Life Cycle Assessment, 2005
    Co-Authors: Gábor Dóka, Roland Hischier
    Abstract:

    Goal, Scope and Background The disposal phase of a product’s life cycle in LCA is often neglected or based on coarse indicators like ‘kilogram waste’. The goal of report No. 13 of the ecoinvent project (Doka 2003) is to create detailed Life Cycle Inventories of waste disposal processes. The purpose of this paper is to give an overview of the models behind the waste disposal inventories in ecoinvent, to present exemplary results and to discuss the assessment of long-term emissions. This paper does not present a particular LCA study. Inventories are compiled for many different materials and various disposal technologies. Considered disposal technologies are municipal incineration and different landfill types, including sanitary landfills, hazardous waste incineration, waste deposits in deep salt mines, surface spreading of sludges, municipal wastewater treatment, and building dismantling. The inventoried technologies are largely based on Swiss plants. Inventories can be used for assessment of the disposal of common, generic waste materials like paper, plastics, packaging etc. Inventories are also used within the ecoinvent database itself to inventory the disposal of specific wastes generated during the production phase. Inventories relate as far as possible to the specific chemical composition of the waste material (waste-specific burdens). Certain expenditures are not related to the waste composition and are inventoried with average values (process-specific burdens). Methods The disposal models are based on previous work, partly used in earlier versions of ecoinvent/ETH LCI data. Important improvements were the extension of the number of considered chemical elements to 41 throughout all disposal models and new landfill models based on field data. New inventories are compiled for waste deposits in deep salt mines and building material disposal. Along with the ecoinvent data and the reports, also Excel-based software tools were created, which allow ecoinvent members to calculate waste disposal inventories from arbitrary waste compositions. The modelling of long-term emissions from landfills is a crucial part in any waste disposal process. In ecoinvent long-term emissions are defined as emissions occurring 100 years after present. They are reported in separate emission categories. The landfill inventories include long-term emissions with a time horizon of 60’000 years after present. Results and Discussion As in earlier studies, the landfills prove to be generally relevant disposal processes, as also incineration and wastewater treatment processes produce landfilled wastes. Heavy metals tend to concentrate in landfills and are washed out to a varying degree over time. Long-term emissions usually represent an important burden from landfills. Comparisons between burdens from production of materials and the burdens from their disposal show that disposal has a certain relevance. Conclusion The disposal phase should by default be included in LCA studies. The use of a material not only necessitates its production, but also requires its disposal. The created inventories and user tools facilitate heeding the disposal phase with a similar level of detail as production processes. The risk of LCA-based decisions shifting burdens from the production or use phase to the disposal phase because of data gaps can therefOre be diminished. Recommendation and Perspective Future improvements should include the modelling of metal Ore Refining waste (tailings) which is currently neglected in ecoinvent, but is likely to be relevant for metals production. The disposal technologies considered here are those of developed Western countries. Disposal in other parts of the World can differ distinctly, for logistic, climatic and economic reasons. The cross-examination of landfill models to LCIA soil fate models could be advantageous. Currently only chemical elements, like copper, zinc, nitrogen etc. are heeded by the disposal models. A possible extension could be the modelling of the behaviour of chemical compounds, like dioxins or other hydrocarbons.

  • Waste Treatment and Assessment of Long-Term Emissions (8pp)
    International Journal of Life Cycle Assessment, 2004
    Co-Authors: Gábor Dóka, Roland Hischier
    Abstract:

    Conclusion. The disposal phase should by default be included in LCA studies. The use of a material not only necessitates its production, but also requires its disposal. The created inven- tories and user tools facilitate heeding the disposal phase with a similar level of detail as production processes. The risk of LCA-based decisions shifting burdens from the production or use phase to the disposal phase because of data gaps can there- fOre be diminished. Recommendation and Perspective. Future improvements should include the modelling of metal Ore Refining waste (tailings) which is currently neglected in ecoinvent, but is likely to be relevant for metals production. The disposal technologies con- sidered here are those of developed Western countries. Dis- posal in other parts of the World can differ distinctly, for logis- tic, climatic and economic reasons. The cross-examination of landfill models to LCIA soil fate models could be advantageous. Currently only chemical elements, like copper, zinc, nitrogen etc. are heeded by the disposal models. A possible extension could be the modelling of the behaviour of chemical compounds, like dioxins or other hydrocarbons. Abstract Goal, Scope and Background. The disposal phase of a product's life cycle in LCA is often neglected or based on coarse indica- tors like 'kilogram waste'. The goal of report No. 13 of the ecoinvent project (Doka 2003) is to create detailed Life Cycle Inventories of waste disposal processes. The purpose of this paper is to give an overview of the models behind the waste disposal inventories in ecoinvent, to present exemplary results and to discuss the assessment of long-term emissions. This paper does not present a particular LCA study. Inventories are compiled for many different materials and various disposal technologies. Considered disposal technologies are municipal incineration and different landfill types, including sanitary landfills, hazardous waste incineration, waste deposits in deep salt mines, surface spreading of sludges, municipal wastewater treatment, and build- ing dismantling. The inventoried technologies are largely based on Swiss plants. Inventories can be used for assessment of the disposal of common, generic waste materials like paper, plas- tics, packaging etc. Inventories are also used within the ecoinvent database itself to inventory the disposal of specific wastes gen- erated during the production phase. Inventories relate as far as possible to the specific chemical composition of the waste mate- rial (waste-specific burdens). Certain expenditures are not re- lated to the waste composition and are inventoried with aver- age values (process-specific burdens). Methods. The disposal models are based on previous work, partly used in earlier versions of ecoinvent/ETH LCI data. Important improvements were the extension of the number of considered chemical elements to 41 throughout all disposal models and new landfill models based on field data. New inventories are compiled for waste deposits in deep salt mines and building ma- terial disposal. Along with the ecoinvent data and the reports, also Excel-based software tools were created, which allow ecoinvent members to calculate waste disposal inventories from arbitrary waste compositions. The modelling of long-term emis- sions from landfills is a crucial part in any waste disposal proc- ess. In ecoinvent long-term emissions are defined as emissions occurring 100 years after present. They are reported in separate emission categories. The landfill inventories include long-term emissions with a time horizon of 60'000 years after present. Results and Discussion. As in earlier studies, the landfills prove to be generally relevant disposal processes, as also incineration and wastewater treatment processes produce landfilled wastes. Heavy metals tend to concentrate in landfills and are washed out to a varying degree over time. Long-term emissions usually represent an important burden from landfills. Comparisons be- tween burdens from production of materials and the burdens from their disposal show that disposal has a certain relevance. 1 Motivation Waste disposal is a somewhat neglected part in life cycle inventories. For production and use phases elaborate data

Dmitrii V. Mescheryakov - One of the best experts on this subject based on the ideXlab platform.

  • Inorganic Wastes in the Manufacture of Glass and Glass‐Ceramics: Quartz‐Feldspar Waste of Ore Refining, Metallurgical Slag, Limestone Dust, and Phosphorus Slurry
    Journal of the American Ceramic Society, 2004
    Co-Authors: Alexander Gorokhovsky, Jose Ivan Escalante-garcia, Vladilen Gorokhovsky, Dmitrii V. Mescheryakov
    Abstract:

    This work presents the results of an investigation on producing diopside glass-ceramic materials based on various combinations of quartz-feldspar waste from Ore Refining and limestone dust. Other industrial wastes were added to contribute as nucleation agents; when the concentration of the latter was insufficient, they were added in the pure state. Additionally, relatively high concentrations of alkalis were used to accelerate glass melting. Low-cost materials with promising exploitation properties were produced. A two-stage regime of crystallization of the basic glass composition was determined, including nucleation at 720°C and crystal growth at 950°C. Local environmental regulations must be considered for the selection of the type of admixtures and the combination of wastes.

  • inorganic wastes in the manufacture of glass and glass ceramics quartz feldspar waste of Ore Refining metallurgical slag limestone dust and phosphorus slurry
    Journal of the American Ceramic Society, 2004
    Co-Authors: Alexander Gorokhovsky, Vladilen Gorokhovsky, J I Escalantegarcia, Dmitrii V. Mescheryakov
    Abstract:

    This work presents the results of an investigation on producing diopside glass-ceramic materials based on various combinations of quartz-feldspar waste from Ore Refining and limestone dust. Other industrial wastes were added to contribute as nucleation agents; when the concentration of the latter was insufficient, they were added in the pure state. Additionally, relatively high concentrations of alkalis were used to accelerate glass melting. Low-cost materials with promising exploitation properties were produced. A two-stage regime of crystallization of the basic glass composition was determined, including nucleation at 720°C and crystal growth at 950°C. Local environmental regulations must be considered for the selection of the type of admixtures and the combination of wastes.

Gábor Dóka - One of the best experts on this subject based on the ideXlab platform.

  • Waste Treatment and Assessment of Long-Term Emissions (8pp)
    The International Journal of Life Cycle Assessment, 2005
    Co-Authors: Gábor Dóka, Roland Hischier
    Abstract:

    Goal, Scope and Background The disposal phase of a product’s life cycle in LCA is often neglected or based on coarse indicators like ‘kilogram waste’. The goal of report No. 13 of the ecoinvent project (Doka 2003) is to create detailed Life Cycle Inventories of waste disposal processes. The purpose of this paper is to give an overview of the models behind the waste disposal inventories in ecoinvent, to present exemplary results and to discuss the assessment of long-term emissions. This paper does not present a particular LCA study. Inventories are compiled for many different materials and various disposal technologies. Considered disposal technologies are municipal incineration and different landfill types, including sanitary landfills, hazardous waste incineration, waste deposits in deep salt mines, surface spreading of sludges, municipal wastewater treatment, and building dismantling. The inventoried technologies are largely based on Swiss plants. Inventories can be used for assessment of the disposal of common, generic waste materials like paper, plastics, packaging etc. Inventories are also used within the ecoinvent database itself to inventory the disposal of specific wastes generated during the production phase. Inventories relate as far as possible to the specific chemical composition of the waste material (waste-specific burdens). Certain expenditures are not related to the waste composition and are inventoried with average values (process-specific burdens). Methods The disposal models are based on previous work, partly used in earlier versions of ecoinvent/ETH LCI data. Important improvements were the extension of the number of considered chemical elements to 41 throughout all disposal models and new landfill models based on field data. New inventories are compiled for waste deposits in deep salt mines and building material disposal. Along with the ecoinvent data and the reports, also Excel-based software tools were created, which allow ecoinvent members to calculate waste disposal inventories from arbitrary waste compositions. The modelling of long-term emissions from landfills is a crucial part in any waste disposal process. In ecoinvent long-term emissions are defined as emissions occurring 100 years after present. They are reported in separate emission categories. The landfill inventories include long-term emissions with a time horizon of 60’000 years after present. Results and Discussion As in earlier studies, the landfills prove to be generally relevant disposal processes, as also incineration and wastewater treatment processes produce landfilled wastes. Heavy metals tend to concentrate in landfills and are washed out to a varying degree over time. Long-term emissions usually represent an important burden from landfills. Comparisons between burdens from production of materials and the burdens from their disposal show that disposal has a certain relevance. Conclusion The disposal phase should by default be included in LCA studies. The use of a material not only necessitates its production, but also requires its disposal. The created inventories and user tools facilitate heeding the disposal phase with a similar level of detail as production processes. The risk of LCA-based decisions shifting burdens from the production or use phase to the disposal phase because of data gaps can therefOre be diminished. Recommendation and Perspective Future improvements should include the modelling of metal Ore Refining waste (tailings) which is currently neglected in ecoinvent, but is likely to be relevant for metals production. The disposal technologies considered here are those of developed Western countries. Disposal in other parts of the World can differ distinctly, for logistic, climatic and economic reasons. The cross-examination of landfill models to LCIA soil fate models could be advantageous. Currently only chemical elements, like copper, zinc, nitrogen etc. are heeded by the disposal models. A possible extension could be the modelling of the behaviour of chemical compounds, like dioxins or other hydrocarbons.

  • Waste Treatment and Assessment of Long-Term Emissions (8pp)
    International Journal of Life Cycle Assessment, 2004
    Co-Authors: Gábor Dóka, Roland Hischier
    Abstract:

    Conclusion. The disposal phase should by default be included in LCA studies. The use of a material not only necessitates its production, but also requires its disposal. The created inven- tories and user tools facilitate heeding the disposal phase with a similar level of detail as production processes. The risk of LCA-based decisions shifting burdens from the production or use phase to the disposal phase because of data gaps can there- fOre be diminished. Recommendation and Perspective. Future improvements should include the modelling of metal Ore Refining waste (tailings) which is currently neglected in ecoinvent, but is likely to be relevant for metals production. The disposal technologies con- sidered here are those of developed Western countries. Dis- posal in other parts of the World can differ distinctly, for logis- tic, climatic and economic reasons. The cross-examination of landfill models to LCIA soil fate models could be advantageous. Currently only chemical elements, like copper, zinc, nitrogen etc. are heeded by the disposal models. A possible extension could be the modelling of the behaviour of chemical compounds, like dioxins or other hydrocarbons. Abstract Goal, Scope and Background. The disposal phase of a product's life cycle in LCA is often neglected or based on coarse indica- tors like 'kilogram waste'. The goal of report No. 13 of the ecoinvent project (Doka 2003) is to create detailed Life Cycle Inventories of waste disposal processes. The purpose of this paper is to give an overview of the models behind the waste disposal inventories in ecoinvent, to present exemplary results and to discuss the assessment of long-term emissions. This paper does not present a particular LCA study. Inventories are compiled for many different materials and various disposal technologies. Considered disposal technologies are municipal incineration and different landfill types, including sanitary landfills, hazardous waste incineration, waste deposits in deep salt mines, surface spreading of sludges, municipal wastewater treatment, and build- ing dismantling. The inventoried technologies are largely based on Swiss plants. Inventories can be used for assessment of the disposal of common, generic waste materials like paper, plas- tics, packaging etc. Inventories are also used within the ecoinvent database itself to inventory the disposal of specific wastes gen- erated during the production phase. Inventories relate as far as possible to the specific chemical composition of the waste mate- rial (waste-specific burdens). Certain expenditures are not re- lated to the waste composition and are inventoried with aver- age values (process-specific burdens). Methods. The disposal models are based on previous work, partly used in earlier versions of ecoinvent/ETH LCI data. Important improvements were the extension of the number of considered chemical elements to 41 throughout all disposal models and new landfill models based on field data. New inventories are compiled for waste deposits in deep salt mines and building ma- terial disposal. Along with the ecoinvent data and the reports, also Excel-based software tools were created, which allow ecoinvent members to calculate waste disposal inventories from arbitrary waste compositions. The modelling of long-term emis- sions from landfills is a crucial part in any waste disposal proc- ess. In ecoinvent long-term emissions are defined as emissions occurring 100 years after present. They are reported in separate emission categories. The landfill inventories include long-term emissions with a time horizon of 60'000 years after present. Results and Discussion. As in earlier studies, the landfills prove to be generally relevant disposal processes, as also incineration and wastewater treatment processes produce landfilled wastes. Heavy metals tend to concentrate in landfills and are washed out to a varying degree over time. Long-term emissions usually represent an important burden from landfills. Comparisons be- tween burdens from production of materials and the burdens from their disposal show that disposal has a certain relevance. 1 Motivation Waste disposal is a somewhat neglected part in life cycle inventories. For production and use phases elaborate data

Alexander Gorokhovsky - One of the best experts on this subject based on the ideXlab platform.

  • Inorganic Wastes in the Manufacture of Glass and Glass‐Ceramics: Quartz‐Feldspar Waste of Ore Refining, Metallurgical Slag, Limestone Dust, and Phosphorus Slurry
    Journal of the American Ceramic Society, 2004
    Co-Authors: Alexander Gorokhovsky, Jose Ivan Escalante-garcia, Vladilen Gorokhovsky, Dmitrii V. Mescheryakov
    Abstract:

    This work presents the results of an investigation on producing diopside glass-ceramic materials based on various combinations of quartz-feldspar waste from Ore Refining and limestone dust. Other industrial wastes were added to contribute as nucleation agents; when the concentration of the latter was insufficient, they were added in the pure state. Additionally, relatively high concentrations of alkalis were used to accelerate glass melting. Low-cost materials with promising exploitation properties were produced. A two-stage regime of crystallization of the basic glass composition was determined, including nucleation at 720°C and crystal growth at 950°C. Local environmental regulations must be considered for the selection of the type of admixtures and the combination of wastes.

  • inorganic wastes in the manufacture of glass and glass ceramics quartz feldspar waste of Ore Refining metallurgical slag limestone dust and phosphorus slurry
    Journal of the American Ceramic Society, 2004
    Co-Authors: Alexander Gorokhovsky, Vladilen Gorokhovsky, J I Escalantegarcia, Dmitrii V. Mescheryakov
    Abstract:

    This work presents the results of an investigation on producing diopside glass-ceramic materials based on various combinations of quartz-feldspar waste from Ore Refining and limestone dust. Other industrial wastes were added to contribute as nucleation agents; when the concentration of the latter was insufficient, they were added in the pure state. Additionally, relatively high concentrations of alkalis were used to accelerate glass melting. Low-cost materials with promising exploitation properties were produced. A two-stage regime of crystallization of the basic glass composition was determined, including nucleation at 720°C and crystal growth at 950°C. Local environmental regulations must be considered for the selection of the type of admixtures and the combination of wastes.

Matthew S Fountain - One of the best experts on this subject based on the ideXlab platform.

  • ion ion interactions enhance aluminum solubility in alkaline suspensions of nano gibbsite α al oh 3 with sodium nitrite nitrate
    Physical Chemistry Chemical Physics, 2020
    Co-Authors: Mateusz Dembowski, Michelle M V Snyder, Calvin H Delegard, Jacob G Reynolds, Trent R Graham, Hsiuwen Wang, Ian I Leavy, Steven R Baum, Odeta Qafoku, Matthew S Fountain
    Abstract:

    Despite widespread industrial importance, predicting metal solubilities in highly concentrated, multicomponent aqueous solutions is difficult due to poorly understood ion–ion and ion–solvent interactions. Aluminum hydroxide solid phase solubility in concentrated sodium hydroxide (NaOH) solutions is one such case, with major implications for Ore Refining, as well as processing of radioactive waste stOred at U.S. Department of Energy legacy sites, such as the Hanford Site, Washington State. The solubility of gibbsite (α-Al(OH)3) is often not well predicted because other ions affect the activity of hydroxide (OH−) and aluminate (Al(OH)4−) anions. In the present study, we systematically examined the influence of key anions, nitrite (NO2−) and nitrate (NO3−), as sodium salts on the solubility of α-Al(OH)3 in NaOH solutions taking care to establish equilibrium from both under- and oversaturation. Rapid equilibration was enabled by use of a highly pure and crystalline synthetic nano-gibbsite of well-defined particle size and shape. Measured dissolved aluminum concentrations were compared with those predicted by an α-Al(OH)3 solubility model derived for simple Al(OH)4−/OH− systems. Specific anion effects were expressed as an enhancement factor (Alenhc) conveying the excess of dissolved aluminum. At 45 °C, NaNO2 and NaNO3-containing systems exhibited Alenhc values of 2.70 and 1.88, respectively, indicating significant enhancement. The solutions were examined by Raman and high-field 27Al NMR spectroscopy, indicating specific interactions including Al(OH)4−–Na+ contact ion pairing and Al(OH)4−–NO2−/NO3− ion–ion interactions. Dynamic evolution of the α-Al(OH)3 particles including growth and agglomeration was observed revealing the importance of dissolution/reprecipitation in establishing equilibrium. These studies indicate that incomplete ion hydration, as a result of the low water activity in these concentrated electrolytes, results in: (i) enhanced reactivity of the hydroxide ion with respect to α-Al(OH)3; (ii) increased concentrations of Al(OH)4− in solution; and (iii) stronger ion–ion interactions that act to stabilize the supersaturated solutions. This information on the mechanisms by which α-Al(OH)3 becomes supersaturated is essential for mOre energy-efficient aluminum processing technologies, including the treatment of millions of gallons of Al(OH)4−-rich high-level radioactive waste.

  • Ion–ion interactions enhance aluminum solubility in alkaline suspensions of nano-gibbsite (α-Al(OH)3) with sodium nitrite/nitrate
    Physical chemistry chemical physics : PCCP, 2019
    Co-Authors: Mateusz Dembowski, Michelle M V Snyder, Calvin H Delegard, Jacob G Reynolds, Trent R Graham, Hsiuwen Wang, Ian I Leavy, Steven R Baum, Odeta Qafoku, Matthew S Fountain
    Abstract:

    Despite widespread industrial importance, predicting metal solubilities in highly concentrated, multicomponent aqueous solutions is difficult due to poorly understood ion–ion and ion–solvent interactions. Aluminum hydroxide solid phase solubility in concentrated sodium hydroxide (NaOH) solutions is one such case, with major implications for Ore Refining, as well as processing of radioactive waste stOred at U.S. Department of Energy legacy sites, such as the Hanford Site, Washington State. The solubility of gibbsite (α-Al(OH)3) is often not well predicted because other ions affect the activity of hydroxide (OH−) and aluminate (Al(OH)4−) anions. In the present study, we systematically examined the influence of key anions, nitrite (NO2−) and nitrate (NO3−), as sodium salts on the solubility of α-Al(OH)3 in NaOH solutions taking care to establish equilibrium from both under- and oversaturation. Rapid equilibration was enabled by use of a highly pure and crystalline synthetic nano-gibbsite of well-defined particle size and shape. Measured dissolved aluminum concentrations were compared with those predicted by an α-Al(OH)3 solubility model derived for simple Al(OH)4−/OH− systems. Specific anion effects were expressed as an enhancement factor (Alenhc) conveying the excess of dissolved aluminum. At 45 °C, NaNO2 and NaNO3-containing systems exhibited Alenhc values of 2.70 and 1.88, respectively, indicating significant enhancement. The solutions were examined by Raman and high-field 27Al NMR spectroscopy, indicating specific interactions including Al(OH)4−–Na+ contact ion pairing and Al(OH)4−–NO2−/NO3− ion–ion interactions. Dynamic evolution of the α-Al(OH)3 particles including growth and agglomeration was observed revealing the importance of dissolution/reprecipitation in establishing equilibrium. These studies indicate that incomplete ion hydration, as a result of the low water activity in these concentrated electrolytes, results in: (i) enhanced reactivity of the hydroxide ion with respect to α-Al(OH)3; (ii) increased concentrations of Al(OH)4− in solution; and (iii) stronger ion–ion interactions that act to stabilize the supersaturated solutions. This information on the mechanisms by which α-Al(OH)3 becomes supersaturated is essential for mOre energy-efficient aluminum processing technologies, including the treatment of millions of gallons of Al(OH)4−-rich high-level radioactive waste.