掺加解毒飞灰的路基材料重金属浸出特征与潜在风险

Heavy Metal Leaching Characteristics and Potential Risk from Subgrade Materials Mixed with Detoxification Fly Ash

垃圾焚烧飞灰属于危险废物,产生量巨大,其资源化利用一直受到人们的关注。为探究掺加解毒飞灰的路基材料的重金属浸出特性和潜在风险,以掺加1%、1.5%、2%、4%二噁英解毒的生活垃圾焚烧飞灰的路基材料为研究对象,研究其Zn、Pb、Cr、Mn、Ni、Cd重金属含量、浸出特性与潜在风险。结果表明:飞灰路基试块浸出液pH为11.5~12.0,不具有强腐蚀性;飞灰路基试块中Cr、Ni、Zn、Cd、Mn、Pb的有效释放量分别为16.00~52.00、14.67~38.00、9.00~293.00、0~7.00、16.00~47.00、46.00~68.67 mg/kg;飞灰路基试块中Cr、Ni、Zn、Cd、Mn、Pb的浸出浓度均低于GB 5085.3—2007危险废物鉴别标准浸出毒性鉴别的标准限值;4个飞灰路基试块中重金属污染物的非致癌危害商分别为7.62×10-4、6.17×10-4、7.43×10-4、8.03×10-4,致癌风险值分别为8.46×10-8、6.34×10-8、9.91×10-8、2.06×10-7,均未超过风险限值,不会对地下水环境质量与人体健康造成影响。

Municiple solid waste incineration(MSWI)fly ash belongs to the hazardous waste with a large amount of output,and its resource utilization has been concerned by researchers.To explore heavy metals leaching characteristics and potential risks of subgrade materials mixed with detoxification fly ash,the subgrade material of MSWI fly ash with 1%,1.5%,2%and 4%dioxin detoxification was taken as the research object,and its Zn,Pb,Cr,Mn,Ni and Cd content,leaching characteristics and potential risks were studied.The result showed that the pH value of the leaching solution of fly ash subgrade test blocks was 11.5~12.0,which was not strongly corrosive.The amount of effective release of Cr,Ni,Zn,Cd,Mn and Pb in fly ash subgrade test blocks were 16.00~52.00,14.67~38.00,9.00~293.00,0~7.00,16.00~47.00,46.00~68.67 mg/kg,respectively,and the leaching concentration were all lower than the standard limit value of Identification Standards for Hazardous Wastes Identification for Extraction Toxicity(GB 5085.3—2007).The non-carcinogenic hazard quotient of heavy metal pollutants in the four test blocks of fly ash subgrade were 7.62×10-4,6.17×10-4,7.43×10-4 and 8.03×10-4 respectively.Meanwhile,the carcinogenic risk valueswere 8.46×10-8,6.34×10-8,9.91×10-8 and 2.06×10-7 respectively,which did not exceed the risk limits and would not affect the groundwater environmental quality and human health.