为了解铅(Pb)、镉(Cd)同位素在重金属污染源解析应用方面的研究进展及未来发展势态,以Web of Science核心数据库中2008-2021年的相关文献为研究对象,运用CiteSpace软件对文献进行可视化分析。结果表明:2008-2021年国际上本研究领域的英...为了解铅(Pb)、镉(Cd)同位素在重金属污染源解析应用方面的研究进展及未来发展势态,以Web of Science核心数据库中2008-2021年的相关文献为研究对象,运用CiteSpace软件对文献进行可视化分析。结果表明:2008-2021年国际上本研究领域的英文发文数量呈波动增长趋势,2015年后文献量增长幅度较大。在此期间,国际上本领域的研究大致划分为2个时期:2008-2014年,研究焦点侧重于工业、采矿、冶炼等行业的重金属污染状况研究,主要涉及大气、水体和沉积物(湖泊、水库和河流)等介质的重金属污染源解析;2015-2021年,研究焦点逐渐转向重金属与人体健康领域,重点关注土壤及农作物重金属的污染源解析、食品安全和人体健康风险评价等问题。总体上,Pb、Cd同位素在重金属污染源解析应用方面的研究由单一同位素解析、单一环境介质应用向多同位素联合解析、多介质应用方向发展。展开更多
Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness...Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness. However, metals contained in fine fraction of PCBs cannot be recovered effectively by conventional equipments such as high tension electrostatic separator or shaking table. In the paper, this conundrum was resolved successfully with the enhanced Falcon SB concentrator. The separation mechanism of Falcon SB concentrator was analyzed and main factors affecting separation efficiency such as magnitude of rotation frequency of bowl, water counter pressure and slurry concentration of feed were studied and interaction of factors above also were investigated using Design-Expert software. Experiment results show that complete liberation degree and great difference of density between metals and nonmetals are suitable to recover metals from -74 μm PCBs using enhanced Falcon SB concentrator and 80.77 % integration efficiency can be achieved when slurry concentration of feed is 40 g/L with the water counter pressure of 0.01 MPa and rotation frequency of 50 Hz.展开更多
Disassembly and recycling of E-waste creates a series of environmental problems. The selection of a technologically reliable, environmentally friendly, economically affordable and socially acceptable recycling technol...Disassembly and recycling of E-waste creates a series of environmental problems. The selection of a technologically reliable, environmentally friendly, economically affordable and socially acceptable recycling technology for E-waste is a significant question. This study establishes a Monte-Carlo mathematical model of cost minimization, given the constraints of environmentally sound handling of the e-waste, in the context of Crystal Ball risk assessment and evaluation software. By following the streams of the different treatment processes, which consist of various technologies including disassembly, recycling and disposal, the econom-ics of various possibilities were identified and the optimal recycling technology proposed. The key factors of the proposed scenarios were determined by using sensitivity analysis. The results of this study show that, for discarded refrigerators, the operating life span plays the key role. The model supports maintenance and resale of the short lived refrigerators. For the longer lived refrigerators material recycling is recommended by the model. Sensitivity analysis shows that purchase cost, plastic sale price, condenser sale price and disassembly costs are the main effects. This study provides a significant technical support for policy making in E-waste management.展开更多
文摘为了解铅(Pb)、镉(Cd)同位素在重金属污染源解析应用方面的研究进展及未来发展势态,以Web of Science核心数据库中2008-2021年的相关文献为研究对象,运用CiteSpace软件对文献进行可视化分析。结果表明:2008-2021年国际上本研究领域的英文发文数量呈波动增长趋势,2015年后文献量增长幅度较大。在此期间,国际上本领域的研究大致划分为2个时期:2008-2014年,研究焦点侧重于工业、采矿、冶炼等行业的重金属污染状况研究,主要涉及大气、水体和沉积物(湖泊、水库和河流)等介质的重金属污染源解析;2015-2021年,研究焦点逐渐转向重金属与人体健康领域,重点关注土壤及农作物重金属的污染源解析、食品安全和人体健康风险评价等问题。总体上,Pb、Cd同位素在重金属污染源解析应用方面的研究由单一同位素解析、单一环境介质应用向多同位素联合解析、多介质应用方向发展。
基金Project 200360290015 supported by the Doctoral Program of Higher Education, China Ministry of Education
文摘Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness. However, metals contained in fine fraction of PCBs cannot be recovered effectively by conventional equipments such as high tension electrostatic separator or shaking table. In the paper, this conundrum was resolved successfully with the enhanced Falcon SB concentrator. The separation mechanism of Falcon SB concentrator was analyzed and main factors affecting separation efficiency such as magnitude of rotation frequency of bowl, water counter pressure and slurry concentration of feed were studied and interaction of factors above also were investigated using Design-Expert software. Experiment results show that complete liberation degree and great difference of density between metals and nonmetals are suitable to recover metals from -74 μm PCBs using enhanced Falcon SB concentrator and 80.77 % integration efficiency can be achieved when slurry concentration of feed is 40 g/L with the water counter pressure of 0.01 MPa and rotation frequency of 50 Hz.
基金Projects 50574094 supported by the National Natural Science Foundation of ChinaCPEUKF06-11 by the Key Laboratory Open Project of Education Ministry of China200600242 by the Science and Technology Innovation Project of Xuzhou
文摘Disassembly and recycling of E-waste creates a series of environmental problems. The selection of a technologically reliable, environmentally friendly, economically affordable and socially acceptable recycling technology for E-waste is a significant question. This study establishes a Monte-Carlo mathematical model of cost minimization, given the constraints of environmentally sound handling of the e-waste, in the context of Crystal Ball risk assessment and evaluation software. By following the streams of the different treatment processes, which consist of various technologies including disassembly, recycling and disposal, the econom-ics of various possibilities were identified and the optimal recycling technology proposed. The key factors of the proposed scenarios were determined by using sensitivity analysis. The results of this study show that, for discarded refrigerators, the operating life span plays the key role. The model supports maintenance and resale of the short lived refrigerators. For the longer lived refrigerators material recycling is recommended by the model. Sensitivity analysis shows that purchase cost, plastic sale price, condenser sale price and disassembly costs are the main effects. This study provides a significant technical support for policy making in E-waste management.
