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Tong Y, Gao J, Yue T, Yuan Y, Tang Y, Wang L. Tracking the flows of Hg, As, Cd, Cr, and Pb in Chinese coal-fired industrial boilers. J Hazard Mater 2024; 466:133678. [PMID: 38310840 DOI: 10.1016/j.jhazmat.2024.133678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/29/2024] [Accepted: 01/29/2024] [Indexed: 02/06/2024]
Abstract
Coal-fired industrial boilers (CFIBs) are critical anthropogenic contributors of heavy metals (HMs) because of their high coal consumption and complicated air pollution control facilities (APCDs). This study explored the flows of Hg, As, Cd, Cr, and Pb in CFIBs at regional scale by establishing a boiler-level HMs inflow-outflow inventory. The results indicate that large-capacity CFIBs (≥ 65 t/h) are the leading contributors to HMs inflows. The inflow intensities of HMs in the provinces exhibited three classes of clustering characteristics. Significant regional heterogeneity was characterized by the distribution of HMs inflows and outflows, with higher HMs inflows and outflows in the northern and east-central coastal areas. However, the relatively low synergistic control efficiency of Cd in Northwest China resulted in a higher contribution of waste than inflow. The wastes generated during the operation of CFIBs are the major outflows of HMs. Hg was observed to have the highest outflow of atmospheric emissions owing to its high volatility. In addition, significant differences in the magnitude of HM outflow were identified among the provinces. The application of efficient APCDs contributes significantly to the partitioning of HMs into waste flows, thereby decreasing regional atmospheric emissions.
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Affiliation(s)
- Yali Tong
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jiajia Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Tao Yue
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | - Yue Yuan
- Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yu Tang
- College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Lingqing Wang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
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2
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Karthik PE, Rajan H, Jothi VR, Sang BI, Yi SC. Electronic wastes: A near inexhaustible and an unimaginably wealthy resource for water splitting electrocatalysts. J Hazard Mater 2022; 421:126687. [PMID: 34332482 DOI: 10.1016/j.jhazmat.2021.126687] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 05/27/2023]
Abstract
E-wastes comprise complex combinations of potentially toxic elements that cause detrimental effects of the environmental contamination; besides their posing threat, most of the products also contain valuable and recoverable materials (Li, Au, Ag, W, Se, Te, etc.), which make them distinct from other forms of industrial wastes. Most of these value-added elements which are primarily employed in electronic goods are disposed of by incineration and land-filling. This is a serious issue besides just environmental pollution, as IUPAC recognized that such ignorance of or poor attention to e-waste recycling has put several elements in the periodic table to the list of endangered elements. Recycling these wastes utilized for electrocatalytic water splitting to produce H2. These recovered e-wastes materials are used as electrocatalysts for the water-splitting, additives to enhance reaction kinetics, and substrate electrodes as well. Recycling and recovery of value-added materials in the view of applying them to electrocatalytic water splitting with endangered elements' perspective have not been covered by any recent review so far. Hence, this review is dedicated to discussing the opportunities available with recycling e-wastes, types of value-added materials that can be recovered for water splitting, strategies exploited, and prospects are discussed in details.
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Affiliation(s)
- Pitchiah Esakki Karthik
- Department of Chemical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Hashikaa Rajan
- Department of Chemical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Vasanth Rajendiran Jothi
- Department of Chemical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Byoung-In Sang
- Department of Chemical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Sung Chul Yi
- Department of Chemical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea; Department of Hydrog en and Fuel cell technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
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3
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Li JJ, Zhao XQ, Wang JL, Shen RF. Strategies of cadmium and copper uptake and translocation in different plant species growing near an E-waste dismantling site at Wenling, China. Environ Sci Pollut Res Int 2021; 28:62562-62571. [PMID: 34212328 DOI: 10.1007/s11356-021-15072-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
This study aimed to explore the interactions between cadmium (Cd) and copper (Cu) during uptake and translocation in plants growing in soil polluted with heavy metals derived from electronic waste (E-waste). We collected the roots, stems, leaves, and root-surrounding soils of ten dominant plant species growing in farmland near an E-waste dismantling site, and analyzed their Cd and Cu concentrations. Among the ten plant species, Echinochloa crus-galli (L.) P. Beauv., Cucurbita moschata (Duch. ex Lam.) Duch. ex Poiret, Phragmites australis (Cav.) Trin. ex Steud., and Benincasa hispida (Thunb.) Cogn. accumulated Cd (2.40-4.56 mg kg-1) and Cu (19.60-35.21 mg kg-1) in the roots. In Polygonum hydropiper L. and Sesbania cannabina (Retz.) Poir., the Cd (0.50-0.81 mg kg-1) and Cu (11.04-15.55 mg kg-1) concentrations were similar among the three organs. Glycine max (L.) Merr. accumulated more Cu in the roots (16.42 mg kg-1) than in the stems (5.61 mg kg-1) and leaves (7.75 mg kg-1), and accumulated Cd at similar levels in the three organs (0.65-0.99 mg kg-1). Sesamum indicum L., Bidens pilosa L., and Solidago decurrens Lour. accumulated Cd at similar levels among the three organs (0.16-3.34 mg kg-1) and accumulated less Cu in the stems (6.89-8.28 mg kg-1) than in the roots (12.61-21.63 mg kg-1) and leaves (12.93-22.38 mg kg-1). S. indicum had a stronger capacity to accumulate and translocate Cd and Cu according to transfer coefficient and translocation factor. The concentrations of Cd and Cu in soils were significantly positively correlated with those in the roots (p<0.01) but not those in the stems and leaves. We detected significantly positive correlations between Cd and Cu concentrations in the roots and leaves (p<0.01) but not in the stems. These results suggest that there is a synergetic strategy of Cd and Cu transport from soils to the roots and from the roots to the leaves, while the stems may not be the key organ controlling Cd and Cu transport in plants. These findings have important implications for the phytoremediation of soils contaminated with Cd and Cu, the mechanisms of plant Cd and Cu transport, and the food safety of agricultural products.
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Affiliation(s)
- Jiao Jiao Li
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xue Qiang Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jia Lin Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ren Fang Shen
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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Islam MT, Huda N. Material flow analysis (MFA) as a strategic tool in E-waste management: Applications, trends and future directions. J Environ Manage 2019; 244:344-361. [PMID: 31129466 DOI: 10.1016/j.jenvman.2019.05.062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 04/16/2019] [Accepted: 05/16/2019] [Indexed: 05/20/2023]
Abstract
Material flow analysis (MFA) is one of the most widely accepted and utilized tools in the industrial-ecology discipline, that measures the input-output materials and examines the pathways and flux of each material flow within the whole system. The application of MFA in e-waste management has recently increased and quite a few academic articles have been published on this issue providing decision support at the policy level. However, there is a need to understand the dynamics of MFA methodology, the data requirements (as well as the data sources used in the previous studies) and the lessons learnt from the studies, so that countries where such an E-waste-MFA study has not yet been performed can apply the international experience of such an emerging research technique. This comprehensive review article presents the recent applications, trends, characteristics, research gaps and challenges of the MFA method that may help e-waste management with an overview of the need for a such tool to be applied. A country-wise analysis is presented and MFA models complemented by various associated methods are summarized with national-level, regional-level, product-level, and element-level assessment. The highlighted future research perspectives discussed in this study will help to analyze e-waste management systems more critically, including the hidden and known flows of waste products and associated materials, economic assessment of material recovery and the role of responsible authorities. This invaluable contribution will help future researchers, particularly from the data collection techniques and previously applied MFA models complemented by various associated methods.
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Affiliation(s)
| | - Nazmul Huda
- School of Engineering, Macquarie University, NSW, 2109, Australia.
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Wang C, Jiang X, Huang R, Cao Y, Xu J, Han Y. Copper/carbon composites from waste printed circuit boards as catalysts for Fenton‐like degradation of Acid Orange 7 enhanced by ultrasound. AIChE J 2019. [DOI: 10.1002/aic.16519] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Chong‐Qing Wang
- Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China
| | - Xiao‐Yan Jiang
- Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China
| | - Rong Huang
- Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China
| | - Yi‐Jun Cao
- Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China
| | - Jing Xu
- State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China
| | - Yi‐Fan Han
- Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China
- State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China
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6
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Zhu F, Xiong Y, Wang Y, Wei X, Zhu X, Yan F. Heavy metal behavior in "Washing-Calcination-Changing with Bottom Ash" system for recycling of four types of fly ashes. Waste Manag 2018; 75:215-225. [PMID: 29395733 DOI: 10.1016/j.wasman.2018.01.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 01/09/2018] [Accepted: 01/23/2018] [Indexed: 06/07/2023]
Abstract
The Washing-Calcination-Changing with Bottom Ash (WCCB) system, effective at reducing chloride, was proposed to treat fly ash (FA) from a municipal solid waste incinerator (MSWI) before recycling FA in cement kiln as raw material. This study analyzed the behavior of heavy metals in four types of FA during WCCB treatment via Tessier and X-ray absorption fine structure (XANES) method. One FA was from the bag filter of a typical MSWI in Beijing, China (CFA), and the other three were from Japan (RFA, CaFA, and NaFA). All the metals were reduced especially Pb, Cd, and Hg (38.4-82.4%, 21.8-34.7%, and 100%, respectively). Besides Cr almost all heavy metals were stabilized according to Tessier analysis. Cr should be given more attention in WCCB as the formation of exchangeable Cr in the final residue. XANES result indicated that PbCl2 could be the main species of Pb in FA, while CaFA contains some PbO. The treated FAs contain PbCO3 and PbO besides PbCl2. The Tessier results of Ni, Pb, Cd, Cr, and Cu showed that NaFA was better at heavy metal stabilization than the other FA, so NaHCO3 is a more suitable neutralizer in WCCB.
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Affiliation(s)
- Fenfen Zhu
- School of Environment & Natural Resources, Renmin University of China, China
| | - Yiqun Xiong
- Department of Environmental Engineering, Kyoto University, Japan.
| | - Yingying Wang
- School of Environment & Natural Resources, Renmin University of China, China
| | - Xiang Wei
- School of Environment & Natural Resources, Renmin University of China, China
| | - Xuemei Zhu
- Chinese Research Academy of Environmental Science, China
| | - Fawei Yan
- School of Environment & Natural Resources, Renmin University of China, China
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Cesaro A, Belgiorno V, Vaccari M, Jandric A, Chung TD, Dias MI, Hursthouse A, Salhofer S. A device-specific prioritization strategy based on the potential for harm to human health in informal WEEE recycling. Environ Sci Pollut Res Int 2018; 25:683-692. [PMID: 29058259 PMCID: PMC5756556 DOI: 10.1007/s11356-017-0390-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/02/2017] [Indexed: 05/03/2023]
Abstract
In developing countries, the recovery of valuable materials from Waste Electrical and Electronic Equipment (WEEE) is carried out via uncontrolled practices, posing potentially severe risks both to human health and the environment. The assessment of the risk, which depends on both the kind and hazardous properties of the substances contained in WEEE, is currently limited as the exposure scenario for the single informal practice cannot be fully characterized for this purpose. In this context, this work proposes and evaluates a strategy to identify the relative potential harm of different kinds of WEEE by their content in metals, selected as the target substances of concern. This was based on the individual metal content, primarily located in the printed circuit boards (PCBs) of the different devices. The metal composition of the individual PCBs was identified and the dominant unregulated metal recovery practices were reviewed to identify the most suitable parameter to express the toxicity of these metals. Based on a mass-normalized cumulative toxicity, via the inhalation route, individual components were assessed from compositional variation found in the literature. The results is a semiquantitative ranking of individual components, revealing significant differences in potential harm posed by different electronic appliances and an opportunity to provide prioritization strategies in future management.
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Affiliation(s)
- Alessandra Cesaro
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II, 84084, Fisciano, SA, Italy.
| | - Vincenzo Belgiorno
- Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II, 84084, Fisciano, SA, Italy
| | | | - Aleksander Jandric
- Waste Management Institute, BOKU University, Muthgasse 107, 1190, Vienna, Austria
| | - Tran Duc Chung
- Waste Management Institute, BOKU University, Muthgasse 107, 1190, Vienna, Austria
| | - Maria Isabel Dias
- Instituto Superior Tecnico, Campus Tecnologico e Nuclear, Universidade de Lisboa, Estrada Nacional 10, Bobadela, 2695-066, Loures, Portugal
| | | | - Stefan Salhofer
- Waste Management Institute, BOKU University, Muthgasse 107, 1190, Vienna, Austria
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Gu F, Ma B, Guo J, Summers PA, Hall P. Internet of things and Big Data as potential solutions to the problems in waste electrical and electronic equipment management: An exploratory study. Waste Manag 2017; 68:434-448. [PMID: 28757222 DOI: 10.1016/j.wasman.2017.07.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 06/29/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
Management of Waste Electrical and Electronic Equipment (WEEE) is a vital part in solid waste management, there are still some difficult issues require attentionss. This paper investigates the potential of applying Internet of Things (IoT) and Big Data as the solutions to the WEEE management problems. The massive data generated during the production, consumption and disposal of Electrical and Electronic Equipment (EEE) fits the characteristics of Big Data. Through using the state-of-the-art communication technologies, the IoT derives the WEEE "Big Data" from the life cycle of EEE, and the Big Data technologies process the WEEE "Big Data" for supporting decision making in WEEE management. The framework of implementing the IoT and the Big Data technologies is proposed, with its multiple layers are illustrated. Case studies with the potential application scenarios of the framework are presented and discussed. As an unprecedented exploration, the combined application of the IoT and the Big Data technologies in WEEE management brings a series of opportunities as well as new challenges. This study provides insights and visions for stakeholders in solving the WEEE management problems under the context of IoT and Big Data.
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Affiliation(s)
- Fu Gu
- Department of Chemical and Environmental Engineering, Nottingham University, Ningbo 315100, China
| | - Buqing Ma
- Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province, College of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jianfeng Guo
- Center of Energy and Environmental Policy Research, Institute of Policy and Management, Chinese Academy of Sciences, Beijing 100190, China.
| | - Peter A Summers
- Department of Chemical and Environmental Engineering, Nottingham University, Ningbo 315100, China
| | - Philip Hall
- Department of Chemical and Environmental Engineering, Nottingham University, Ningbo 315100, China
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Abstract
With the development of technologies and the change of consumer attitudes, the amount of waste electrical and electronic equipment (WEEE) is increasing annually. As the core part of WEEE, the waste printed circuit board (WPCB) is a dangerous waste but at the same time a rich resource for various kinds of materials. In this work, various WPCB treatment methods as well as WPCB recycling techniques divided into direct treatment (landfill and incineration), primitive recycling technology (pyrometallurgy, hydrometallurgy, biometallurgy and primitive full recovery of NMF-non metallic fraction), and advanced recycling technology (mechanical separation, direct use and modification of NMF) are reviewed and analyzed based on their advantages and disadvantages. Also, the evaluation criteria are discussed including economic, environmental, and gate-to-market ability. This review indicates the future research direction of WPCB recycling should focus on a combination of several techniques or in series recycling to maximize the benefits of process.
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Affiliation(s)
- Chao Ning
- Chemical and Biomolecular Engineering Department, The Hong Kong University of Science and Technology, Hong Kong SAR, Hong Kong
| | - Carol Sze Ki Lin
- School of Energy and Environment, The City University of Hong Kong, Tat Chee Avenue, Hong Kong SAR, Hong Kong
| | - David Chi Wai Hui
- Chemical and Biomolecular Engineering Department, The Hong Kong University of Science and Technology, Hong Kong SAR, Hong Kong
| | - Gordon McKay
- Chemical and Biomolecular Engineering Department, The Hong Kong University of Science and Technology, Hong Kong SAR, Hong Kong. .,College of Science and Engineering, Hamad bin Khalifa University, Education City, Qatar Foundation, Doha, Qatar.
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Tao XQ, Shen DS, Shentu JL, Long YY, Feng YJ, Shen CC. Bioaccessibility and health risk of heavy metals in ash from the incineration of different e-waste residues. Environ Sci Pollut Res Int 2015; 22:3558-3569. [PMID: 25249049 DOI: 10.1007/s11356-014-3562-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 09/03/2014] [Indexed: 06/03/2023]
Abstract
Ash from incinerated e-waste dismantling residues (EDR) may cause significant health risks to people through ingestion, inhalation, and dermal contact exposure pathways. Ashes of four classified e-waste types generated by an incineration plant in Zhejiang, China were collected. Total contents and the bioaccessibilities of Cd, Cu, Ni, Pb, and Zn in ashes were measured to provide crucial information to evaluate the health risks for incinerator workers and children living in vicinity. Compared to raw e-waste in mixture, ash was metal-enriched by category incinerated. However, the physiologically based extraction test (PBET) indicates the bioaccessibilities of Ni, Pb, and Zn were less than 50 %. Obviously, bioaccessibilities need to be considered in noncancer risk estimate. Total and PBET-extractable contents of metal, except for Pb, were significantly correlated with the pH of the ash. Noncancer risks of ash from different incinerator parts decreased in the order bag filter ash (BFA) > cyclone separator ash (CFA) > bottom ash (BA). The hazard quotient for exposure to ash were decreased as ingestion > dermal contact > inhalation. Pb in ingested ash dominated (>80 %) noncancer risks, and children had high chronic risks from Pb (hazard index >10). Carcinogenic risks from exposure to ash were under the acceptable level (<10(-6)) both for children and workers. Exposure to ash increased workers' cancer risks and children's noncancer risks. Given the risk estimate is complex including toxicity/bioaccessibility of metals, the ways of exposure, and many uncertainties, further researches are required before any definite decisions on mitigating health risks caused by exposure to EDR incinerated ash are made.
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Affiliation(s)
- Xiao-Qing Tao
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, People's Republic of China
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11
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Huang CL, Ma HW, Yu CP. Substance flow analysis and assessment of environmental exposure potential for triclosan in mainland China. Sci Total Environ 2014; 499:265-75. [PMID: 25194904 DOI: 10.1016/j.scitotenv.2014.08.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 08/09/2014] [Accepted: 08/10/2014] [Indexed: 05/05/2023]
Abstract
Triclosan (TCS) is a widely-used antimicrobial agent in many consumer products around the world, and China is a major producer and consumer of TCS. In this study substance flow analysis (SFA) was used to construct a static model of anthropogenic TCS metabolism in China in 2008. The systematic SFA results were used to determine possible exposure pathways and trends in environmental exposure potential through different pathways. TCS discharged in wastewater mainly flowed into surface water sediment, ocean, and soil, where it accumulates in aquatic and agricultural products that may pose a higher risk to human health than brief exposure during consumption. Only 22% of TCS discharged was removed in the built environment with the remainder discharged into the natural environment, indicating that anthropogenic TCS metabolism in China is unsustainable. Per capita TCS consumption increased 209% from 2003 to 2012, resulting in increased discharge and accumulation in the environment. If current trends continue, it will increase to 713 mg capita(-1) yr(-1) in 2015 and 957 mg capita(-1) yr(-1) in 2020. Accordingly, annual environmental exposure potential will increase from 388 mg capita(-1) in 2008 to 557 mg capita(-1) in 2015 and 747 mg capita(-1) in 2020, indicating an increasing trend of exposure to environmental TCS. Results of Pearson correlation analysis suggested that feasible countermeasures to reduce environmental exposure potential for triclosan would include encouraging the development of small cities, raising awareness of health risks, nurturing environmentally-friendly consumer values, and improving the environmental performance of TCS-containing products.
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Affiliation(s)
- Chu-Long Huang
- Institute of Urban Environment, Chinese Academy of Sciences, 1799, Jimei Road, Xiamen 361021, China; Department of Resources and Environmental Sciences, Quanzhou Normal University, 398, Donghai Street, Quanzhou 362000, China
| | - Hwong-Wen Ma
- Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Road, Taipei 10660, Taiwan
| | - Chang-Ping Yu
- Institute of Urban Environment, Chinese Academy of Sciences, 1799, Jimei Road, Xiamen 361021, China.
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12
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Hadi P, Xu M, Lin CSK, Hui CW, McKay G. Waste printed circuit board recycling techniques and product utilization. J Hazard Mater 2014; 283:234-243. [PMID: 25285997 DOI: 10.1016/j.jhazmat.2014.09.032] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 09/02/2014] [Accepted: 09/08/2014] [Indexed: 06/03/2023]
Abstract
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.
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Affiliation(s)
- Pejman Hadi
- Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region
| | - Meng Xu
- Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region
| | - Carol S K Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - Chi-Wai Hui
- Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region
| | - Gordon McKay
- Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region; Division of Sustainable Development, College of Science, Engineering and Technology, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar.
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13
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Long YY, Feng YJ, Cai SS, Hu LF, Shen DS. Reduction of heavy metals in residues from the dismantling of waste electrical and electronic equipment before incineration. J Hazard Mater 2014; 272:59-65. [PMID: 24681442 DOI: 10.1016/j.jhazmat.2014.02.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Revised: 02/09/2014] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
Residues disposal from the dismantling of waste electrical and electronic equipment are challenging because of the large waste volumes, degradation-resistance, low density and high heavy metal content. Incineration is advantageous for treating these residues but high heavy metal contents may exist in incinerator input and output streams. We have developed and studied a specialized heavy metal reduction process, which includes sieving and washing for treating residues before incineration. The preferable screen aperture for sieving was found to be 2.36mm (8 meshes) in this study; using this screen aperture resulted in the removal of approximately 47.2% Cu, 65.9% Zn, 26.5% Pb, 55.4% Ni and 58.8% Cd from the residues. Subsequent washing further reduces the heavy metal content in the residues larger than 2.36mm, with preferable conditions being 400rpm rotation speed, 5min washing duration and liquid-to-solid ratio of 25:1. The highest cumulative removal efficiencies of Cu, Zn, Pb, Ni and Cd after sieving and washing reached 81.1%, 61.4%, 75.8%, 97.2% and 72.7%, respectively. The combined sieving and washing process is environmentally friendly, can be used for the removal of heavy metals from the residues and has benefits in terms of heavy metal recycling.
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Affiliation(s)
- Yu-Yang Long
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China
| | - Yi-Jian Feng
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China
| | - Si-Shi Cai
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China
| | - Li-Fang Hu
- College of Quality and Safety Engineering, China Jiliang University, Hangzhou 310018, China
| | - Dong-Sheng Shen
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China.
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