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Ann-margret Hvitt Strömvall - One of the best experts on this subject based on the ideXlab platform.

  • remediation of metal polluted hotspot areas through enhanced soil washing evaluation of leaching methods
    Journal of Environmental Management, 2013
    Co-Authors: Karin Karlfeldt Fedje, L Yillin, Ann-margret Hvitt Strömvall
    Abstract:

    Soil washing offers a permanent remediation alternative for metal polluted sites. In addition, the washed out metals can be recovered from the leachate and re-introduced into the social Material Cycle instead of landfilled. In this paper, soil, bark and bark-ash washing was tested on four different metal polluted soil and bark samples from hotspots at former industrial sites. Six different leaching agents; HCl, NR4Cl, lactic acid, EDDS and two acidic process waters from solid waste incineration, were tested, discussed and evaluated. For the soil washing processes, the final pH in the leachate strongly influences the metal leachability. The results show that a pH 99% purity) could be recovered. After a single leaching step, the metal contents of the soil residues still exceed the maximum limits according to the Swedish guidelines. An additional washing step is needed to reduce the contents of easy soluble metal compounds in the soil residues. The overall results from this study show that soil and bark-ash washing followed by metal recovery is a promising on-site permanent alternative to remediate metal polluted soils and to utilize non-used metal resources.

  • remediation of metal polluted hotspot areas through enhanced soil washing evaluation of leaching methods
    Journal of Environmental Management, 2013
    Co-Authors: Karin Karlfeldt Fedje, L Yillin, Ann-margret Hvitt Strömvall
    Abstract:

    Soil washing offers a permanent remediation alternative for metal polluted sites. In addition, the washed out metals can be recovered from the leachate and re-introduced into the social Material Cycle instead of landfilled. In this paper, soil, bark and bark-ash washing was tested on four different metal polluted soil and bark samples from hotspots at former industrial sites. Six different leaching agents; HCl, NR4Cl, lactic acid, EDDS and two acidic process waters from solid waste incineration, were tested, discussed and evaluated. For the soil washing processes, the final pH in the leachate strongly influences the metal leachability. The results show that a pH 99% purity) could be recovered. After a single leaching step, the metal contents of the soil residues still exceed the maximum limits according to the Swedish guidelines. An additional washing step is needed to reduce the contents of easy soluble metal compounds in the soil residues. The overall results from this study show that soil and bark-ash washing followed by metal recovery is a promising on-site permanent alternative to remediate metal polluted soils and to utilize non-used metal resources.

Chris Hendrickson - One of the best experts on this subject based on the ideXlab platform.

  • Closing the Loop on Cadmium - An Assessment of the Material Cycle of Cadmium in the U.S. (11 pp)
    The International Journal of Life Cycle Assessment, 2006
    Co-Authors: Troy R. Hawkins, Scott Matthews, Chris Hendrickson
    Abstract:

    Goal, Scope and Background In this study, the major flows of cadmium in the U.S. economy are quantified and the primary sinks are identified to gauge the need for additional policy to minimize the potential human health and ecosystem risks associated with these flows. Because of the concurrent occurrence of cadmium and zinc in ore, we also consider the relevant portions of the Material Cycle of zinc.

  • An Assessment of the Material Cycle of Cadmium in the U.S.
    2006
    Co-Authors: Troy R. Hawkins, H. Scott Matthews, Chris Hendrickson
    Abstract:

    Goal, Scope and Background. In this study, the major flows of cadmium in the U.S. economy are quantified and the primary sinks are identified to gauge the need for additional policy to minimize the potential human health and ecosystem risks associated with these flows. Because of the concurrent occurrence of cadmium and zinc in ore, we also consider the relevant portions of the Material Cycle of zinc. Methods. We estimated the flows of cadmium through U.S. manufacturing using a mass balance approach with data provided by the U.S. Geological Survey's Minerals Yearbook. Cadmium emissions factors were created using facility specific information found in the U.S. Toxics Release Inventory and were used to model future losses. Data gaps were filled through review of relevant literature. We modeled the import and sales of nickel-cadmium batteries with rechargeable battery usage trends and estimates of market share by battery chemistry. Results and Conclusion. Primary cadmium in the U.S. is almost exclusively produced as a co-product of zinc. Almost all zinc and cadmium mined in the U.S. is exported to foreign smelters as ore concentrate. We estimate that the bulk of cadmium consumed in the U.S. economy (~90%) is imported in the form of nickel-cadmium rechargeable batteries. These batteries can be divided into the larger wet-cells and portable rechargeable batteries (PRB). The collection rate for the recycling of large wet cells was found to be high (80%) while the collection rate for PRBs is low (5–20%). The Rechargeable Battery Recycling Corporation (RBRC) is responsible for the collection of these batteries which are reCycled exclusively by the International Materials Reclamation Company (INMETCO). The remaining PRBs are generally disposed of in municipal solid waste (MSW) landfills. This study provides a detailed substance flow analysis of U.S. stocks and flows of cadmium in products, however additional research is needed to better quantify the associated exposures and risks. Recommendation and Perspective. Based on our analysis, we make four recommendations. First we suggest that if cadmium is to be used, it should be used in long-lived products that can be easily collected and reCycled with minimal losses. Second, continued cadmium use should be coupled with renewed efforts on the part of policy-makers to encourage the collection and recycling of cadmium-bearing products. At present, consumers do not see the environmental cost associated with the proper disposal of the cadmium content of NiCd batteries. Policy op

  • Closing the Loop on Cadmium - An Assessment of the Material Cycle of Cadmium in the U.S. (11 pp)
    The International Journal of Life Cycle Assessment, 2006
    Co-Authors: Troy Hawkins, Scott Matthews, Chris Hendrickson
    Abstract:

    Goal, Scope and Background In this study, the major flows of cadmium in the U.S. economy are quantified and the primary sinks are identified to gauge the need for additional policy to minimize the potential human health and ecosystem risks associated with these flows. Because of the concurrent occurrence of cadmium and zinc in ore, we also consider the relevant portions of the Material Cycle of zinc. Methods We estimated the flows of cadmium through U.S. manufacturing using a mass balance approach with data provided by the U.S. Geological Survey's Minerals Yearbook. Cadmium emissions factors were created using facility specific information found in the U.S. Toxics Release Inventory and were used to model future losses. Data gaps were filled through review of relevant literature. We modeled the import and sales of nickel-cadmium batteries with rechargeable battery usage trends and estimates of market share by battery chemistry. Results and Conclusion Primary cadmium in the U.S. is almost exclusively produced as a co-product of zinc. Almost all zinc and cadmium mined in the U.S. is exported to foreign smelters as ore concentrate. We estimate that the bulk of cadmium consumed in the U.S. economy (~90%) is imported in the form of nickel-cadmium rechargeable batteries. These batteries can be divided into the larger wet-cells and portable rechargeable batteries (PRB). The collection rate for the recycling of large wet cells was found to be high (80%) while the collection rate for PRBs is low (5-20%). The Rechargeable Battery Recycling Corporation (RBRC) is responsible for the collection of these batteries which are reCycled exclusively by the International Materials Reclamation Company (INMETCO). The remaining PRBs are generally disposed of in municipal solid waste (MSW) landfills. This study provides a detailed substance flow analysis of U.S. stocks and flows of cadmium in products, however additional research is needed to better quantify the associated exposures and risks. Recommendation and Perspective Based on our analysis, we make four recommendations. First we suggest that if cadmium is to be used, it should be used in long-lived products that can be easily collected and reCycled with minimal losses. Second, continued cadmium use should be coupled with renewed efforts on the part of policy-makers to encourage the collection and recycling of cadmium-bearing products. At present, consumers do not see the environmental cost associated with the proper disposal of the cadmium content of NiCd batteries. Policy options for improving recycling rates include collecting deposits and providing rewards for the return of spent batteries, taxing or otherwise discouraging discarding PRBs in municipal solid waste, and providing incentives for extended producer responsibility. Third, we highlight the importance of the connection between zinc mining and the supply of cadmium in designing an effective policy to manage the risks associated with cadmium. Fourth, we recommend that policy measures be taken to provide the necessary data required to improve our understanding of the flow of cadmium into the U.S. in the form of product imports and the amount of cadmium lost or disposed of by recycling processes.

Wei-qiang Chen - One of the best experts on this subject based on the ideXlab platform.

  • Refining the understanding of China's tungsten dominance with dynamic Material Cycle analysis
    Resources Conservation and Recycling, 2020
    Co-Authors: Linbin Tang, Peng Wang, Thomas E. Graedel, Stefan Pauliuk, Keying Xiang, Yan Ren, Wei-qiang Chen
    Abstract:

    Abstract Tungsten is deemed a critical raw Material by many nations, given its irreplaceable use in industrial and military applications. In particular, much concern has been drawn to China's high share in global tungsten supply. While various studies have focused on the criticality of tungsten, few have specifically explored how tungsten is produced, consumed, and traded. In this paper, the dynamic Material flow analysis is applied to quantify China's annual tungsten Cycle from 1949 – 2017. It is estimated that total tungsten mined from ores in China over the past 68-year period is ~2500 kilo-tons (kt). Among those, ~750 kt of tungsten has been exported to other countries, and around 970 kt tungsten is domestically consumed. It is noted ≈1720 kt has been lost from mining, production, and end-of-life stage, and merely ~130 kt has been reCycled as end-of-life scrap. Our Material flow analysis further refined China's tungsten dominance. Although China currently dominates the global production of tungsten, this dominance will not extend too far into the future given China's limited share of world tungsten reserves and its declining ore quality. Our trade flow analysis reveals that China imported ~35 kt of high value-added downstream tungsten products from outside manufacturers, whose mineral resource was originally imported from China. At present, China by itself is experiencing overcapacity issues in the primary production, which discourages the recycling of at end-of-life (EoL) stage and makes the EoL recycling rate only 10%. It is noted that the percentage of Chinese tungsten for domestic consumption has been increasing in the past few years. This highlights the need for systematic measures from stakeholders along the tungsten Cycle to promote sustainable practices for efficient tungsten production, use, and recycling in China. Meanwhile, the results also suggest the importance of monitoring the criticality of tungsten and other critical minerals from a dynamic and Material Cycle perspective.

  • incorporating critical Material Cycles into metal energy nexus of china s 2050 renewable transition
    Applied Energy, 2019
    Co-Authors: Peng Wang, Li-yang Chen, Wenjia Cai, Wei-qiang Chen
    Abstract:

    Abstract Renewables rely heavily on critical Materials. Such Material (metal)-energy nexus thinking is critical to guarantee global renewable transition. As the largest energy consumer, China aims to promote the unprecedented installation of renewables to significantly decarbonize energy system till 2050. However, the Material constraints to those renewable targets have been widely neglected by current stakeholders in China. In this paper, a quantitative framework is proposed to identify and quantify the corresponding Material constraints on energy transition from a Material Cycle perspective. Accordingly, the required critical Material demand for China’s 2050 renewable transition and its flow, loss, and stock along the life Cycle are quantified. It is found that the critical Materials (i.e. Cadmium, Tellurium, Indium, Gallium, Selenium, and Germanium) required by solar power in China are all under high shortage and supply risk. Their cumulative demand from 2015 to 2050 will exceeded the present national reserve by 1.4–123-fold. Approximately 804–1056 thousand tons (kt) of Neodymium and 66–85 kt of Dysprosium are required to support the growth of wind power, which account for around 10% with the current reserve in China. Nevertheless, the limited scalability of rare earth production in China may still constrain wind power development. Hence, China should adjust its renewable pathways (e.g. more wind, less solar) based on the critical mineral endowment. Furthermore, recycling is preferred but has limited impact on Material criticality mitigation before 2030, and it is then suggested more actions should be made on the international trade and Material efficiency improvement along the life Cycle to support future renewable needs.

  • Incorporating critical Material Cycles into metal-energy nexus of China’s 2050 renewable transition
    Applied Energy, 2019
    Co-Authors: Peng Wang, Li-yang Chen, Wenjia Cai, Wei-qiang Chen
    Abstract:

    Abstract Renewables rely heavily on critical Materials. Such Material (metal)-energy nexus thinking is critical to guarantee global renewable transition. As the largest energy consumer, China aims to promote the unprecedented installation of renewables to significantly decarbonize energy system till 2050. However, the Material constraints to those renewable targets have been widely neglected by current stakeholders in China. In this paper, a quantitative framework is proposed to identify and quantify the corresponding Material constraints on energy transition from a Material Cycle perspective. Accordingly, the required critical Material demand for China’s 2050 renewable transition and its flow, loss, and stock along the life Cycle are quantified. It is found that the critical Materials (i.e. Cadmium, Tellurium, Indium, Gallium, Selenium, and Germanium) required by solar power in China are all under high shortage and supply risk. Their cumulative demand from 2015 to 2050 will exceeded the present national reserve by 1.4–123-fold. Approximately 804–1056 thousand tons (kt) of Neodymium and 66–85 kt of Dysprosium are required to support the growth of wind power, which account for around 10% with the current reserve in China. Nevertheless, the limited scalability of rare earth production in China may still constrain wind power development. Hence, China should adjust its renewable pathways (e.g. more wind, less solar) based on the critical mineral endowment. Furthermore, recycling is preferred but has limited impact on Material criticality mitigation before 2030, and it is then suggested more actions should be made on the international trade and Material efficiency improvement along the life Cycle to support future renewable needs.

Peng Wang - One of the best experts on this subject based on the ideXlab platform.

  • Refining the understanding of China's tungsten dominance with dynamic Material Cycle analysis
    Resources Conservation and Recycling, 2020
    Co-Authors: Linbin Tang, Peng Wang, Thomas E. Graedel, Stefan Pauliuk, Keying Xiang, Yan Ren, Wei-qiang Chen
    Abstract:

    Abstract Tungsten is deemed a critical raw Material by many nations, given its irreplaceable use in industrial and military applications. In particular, much concern has been drawn to China's high share in global tungsten supply. While various studies have focused on the criticality of tungsten, few have specifically explored how tungsten is produced, consumed, and traded. In this paper, the dynamic Material flow analysis is applied to quantify China's annual tungsten Cycle from 1949 – 2017. It is estimated that total tungsten mined from ores in China over the past 68-year period is ~2500 kilo-tons (kt). Among those, ~750 kt of tungsten has been exported to other countries, and around 970 kt tungsten is domestically consumed. It is noted ≈1720 kt has been lost from mining, production, and end-of-life stage, and merely ~130 kt has been reCycled as end-of-life scrap. Our Material flow analysis further refined China's tungsten dominance. Although China currently dominates the global production of tungsten, this dominance will not extend too far into the future given China's limited share of world tungsten reserves and its declining ore quality. Our trade flow analysis reveals that China imported ~35 kt of high value-added downstream tungsten products from outside manufacturers, whose mineral resource was originally imported from China. At present, China by itself is experiencing overcapacity issues in the primary production, which discourages the recycling of at end-of-life (EoL) stage and makes the EoL recycling rate only 10%. It is noted that the percentage of Chinese tungsten for domestic consumption has been increasing in the past few years. This highlights the need for systematic measures from stakeholders along the tungsten Cycle to promote sustainable practices for efficient tungsten production, use, and recycling in China. Meanwhile, the results also suggest the importance of monitoring the criticality of tungsten and other critical minerals from a dynamic and Material Cycle perspective.

  • incorporating critical Material Cycles into metal energy nexus of china s 2050 renewable transition
    Applied Energy, 2019
    Co-Authors: Peng Wang, Li-yang Chen, Wenjia Cai, Wei-qiang Chen
    Abstract:

    Abstract Renewables rely heavily on critical Materials. Such Material (metal)-energy nexus thinking is critical to guarantee global renewable transition. As the largest energy consumer, China aims to promote the unprecedented installation of renewables to significantly decarbonize energy system till 2050. However, the Material constraints to those renewable targets have been widely neglected by current stakeholders in China. In this paper, a quantitative framework is proposed to identify and quantify the corresponding Material constraints on energy transition from a Material Cycle perspective. Accordingly, the required critical Material demand for China’s 2050 renewable transition and its flow, loss, and stock along the life Cycle are quantified. It is found that the critical Materials (i.e. Cadmium, Tellurium, Indium, Gallium, Selenium, and Germanium) required by solar power in China are all under high shortage and supply risk. Their cumulative demand from 2015 to 2050 will exceeded the present national reserve by 1.4–123-fold. Approximately 804–1056 thousand tons (kt) of Neodymium and 66–85 kt of Dysprosium are required to support the growth of wind power, which account for around 10% with the current reserve in China. Nevertheless, the limited scalability of rare earth production in China may still constrain wind power development. Hence, China should adjust its renewable pathways (e.g. more wind, less solar) based on the critical mineral endowment. Furthermore, recycling is preferred but has limited impact on Material criticality mitigation before 2030, and it is then suggested more actions should be made on the international trade and Material efficiency improvement along the life Cycle to support future renewable needs.

  • Incorporating critical Material Cycles into metal-energy nexus of China’s 2050 renewable transition
    Applied Energy, 2019
    Co-Authors: Peng Wang, Li-yang Chen, Wenjia Cai, Wei-qiang Chen
    Abstract:

    Abstract Renewables rely heavily on critical Materials. Such Material (metal)-energy nexus thinking is critical to guarantee global renewable transition. As the largest energy consumer, China aims to promote the unprecedented installation of renewables to significantly decarbonize energy system till 2050. However, the Material constraints to those renewable targets have been widely neglected by current stakeholders in China. In this paper, a quantitative framework is proposed to identify and quantify the corresponding Material constraints on energy transition from a Material Cycle perspective. Accordingly, the required critical Material demand for China’s 2050 renewable transition and its flow, loss, and stock along the life Cycle are quantified. It is found that the critical Materials (i.e. Cadmium, Tellurium, Indium, Gallium, Selenium, and Germanium) required by solar power in China are all under high shortage and supply risk. Their cumulative demand from 2015 to 2050 will exceeded the present national reserve by 1.4–123-fold. Approximately 804–1056 thousand tons (kt) of Neodymium and 66–85 kt of Dysprosium are required to support the growth of wind power, which account for around 10% with the current reserve in China. Nevertheless, the limited scalability of rare earth production in China may still constrain wind power development. Hence, China should adjust its renewable pathways (e.g. more wind, less solar) based on the critical mineral endowment. Furthermore, recycling is preferred but has limited impact on Material criticality mitigation before 2030, and it is then suggested more actions should be made on the international trade and Material efficiency improvement along the life Cycle to support future renewable needs.

Karin Karlfeldt Fedje - One of the best experts on this subject based on the ideXlab platform.

  • remediation of metal polluted hotspot areas through enhanced soil washing evaluation of leaching methods
    Journal of Environmental Management, 2013
    Co-Authors: Karin Karlfeldt Fedje, L Yillin, Ann-margret Hvitt Strömvall
    Abstract:

    Soil washing offers a permanent remediation alternative for metal polluted sites. In addition, the washed out metals can be recovered from the leachate and re-introduced into the social Material Cycle instead of landfilled. In this paper, soil, bark and bark-ash washing was tested on four different metal polluted soil and bark samples from hotspots at former industrial sites. Six different leaching agents; HCl, NR4Cl, lactic acid, EDDS and two acidic process waters from solid waste incineration, were tested, discussed and evaluated. For the soil washing processes, the final pH in the leachate strongly influences the metal leachability. The results show that a pH 99% purity) could be recovered. After a single leaching step, the metal contents of the soil residues still exceed the maximum limits according to the Swedish guidelines. An additional washing step is needed to reduce the contents of easy soluble metal compounds in the soil residues. The overall results from this study show that soil and bark-ash washing followed by metal recovery is a promising on-site permanent alternative to remediate metal polluted soils and to utilize non-used metal resources.

  • remediation of metal polluted hotspot areas through enhanced soil washing evaluation of leaching methods
    Journal of Environmental Management, 2013
    Co-Authors: Karin Karlfeldt Fedje, L Yillin, Ann-margret Hvitt Strömvall
    Abstract:

    Soil washing offers a permanent remediation alternative for metal polluted sites. In addition, the washed out metals can be recovered from the leachate and re-introduced into the social Material Cycle instead of landfilled. In this paper, soil, bark and bark-ash washing was tested on four different metal polluted soil and bark samples from hotspots at former industrial sites. Six different leaching agents; HCl, NR4Cl, lactic acid, EDDS and two acidic process waters from solid waste incineration, were tested, discussed and evaluated. For the soil washing processes, the final pH in the leachate strongly influences the metal leachability. The results show that a pH 99% purity) could be recovered. After a single leaching step, the metal contents of the soil residues still exceed the maximum limits according to the Swedish guidelines. An additional washing step is needed to reduce the contents of easy soluble metal compounds in the soil residues. The overall results from this study show that soil and bark-ash washing followed by metal recovery is a promising on-site permanent alternative to remediate metal polluted soils and to utilize non-used metal resources.