工业固体废物电石渣农用的环境安全风险

Environmental safety risk for application of industrial solid wastes carbide slag in soil

电石渣是电石法聚氯乙烯(PVC)生产过程中产生的工业固体废渣。为解决电石渣堆积带来的环境问题,其资源化利用受到关注。然而,在电石法PVC生产过程中,电石渣中会带入一些有毒有害元素,主要含有镉(Cd)、镍(Ni)、氯(Cl^-)和氰化物(CN^-)等污染元素。研究数据显示:电石渣中污染元素Cd、Ni、CN^-和Cl^-等含量存在不同程度超出国家土壤环境质量标准和地下水质量标准(包括As和Pb)。为保证土壤健康、食品安全和环境安全,建议未经无害化处理、有害物质超标的、存在环境安全风险的电石渣等工业固体废物不得直接施用于农田土壤,杜绝其进入食物链而危害人类健康。

Carbide slag is an industrial solid waste produced in polyvinyl chloride(PVC) production by calcium carbide process.The resource utilization of carbide slag has attracted much attention for solving the problem with carbide slag disposal in the PVC production industry.However,some poisonous and harmful elements will transfer into carbide slag inthe PVC production by calcium carbide process,resulting in the enrichment of several hazardous pollutants in carbide slag(mainly Cd,Ni,Cl^-and cyanide).Research results indicate that the enrichment of pollutants can result in high levels of pollutant elements(especially Cd,Ni and Cl^-) in some carbide slags in China,even far beyond the limits of Environmental Quality Standards for Soils,and the limits of Environmental Quality Standards for Ground Water.In order to ensure soil health,food safety,and environmental quality,it is suggested that those industrial solid wastes such as calcium carbide slag without any harmless treatment of pollutants should not be allowed to use as for soil remediation or conditioning directly into the farmlands by solid waste disposal methods,to prevent pollutants from entering food chain and harming to human health.