北天堂垃圾污染场地氧化还原分带及污染物自然衰减研究

Contaminants Natural Attenuation of Beitiantang Landfills Leachate Polluted Sites

通过对北京市北天堂垃圾填埋场周围实际监测数据资料的分析,研究了垃圾填埋污染场地的氧化还原分带和污染物的自然衰减作用.结果表明,北天堂垃圾填埋污染场地存在氧化还原分带现象,依据各氧化还原带标志性物质浓度的分布规律和特点划分了5个氧化还原带,即产甲烷带、硫酸盐还原带、铁还原带、硝酸盐还原带和氧还原带.不同有机污染物在不同的氧化还原带中的衰减不同;挥发酚和氰化物在硫酸盐还原带中的含量相对较高,分别为0.005和0.019μg/L;Cr、Pb、Ni、As、Cu、Cd、Zn和Mn等重金属在产甲烷带中的含量相对较高,分别为25.11、33.82、29.93、3.18、2.3、0.1、283.1、1220μg/L.因此,氧化还原带对污染物的衰减起重要作用.

Redox zones and the natural attenuation of pollutants in landfill leachate polluted site through analyzing data monitored around the Beitiantang Landfills of Beijing City. The results indicated that redox zones existed in Beitiantang Landfill leachate polluted sites, and 5 redox zones were classified depended on distribution rules and characteristics of indicative substrates, namely methanogenic zone, sulfate reduction zone, iron reduction zone, nitrate reduction zone and oxygen reduction zone. Attenuation efficiencies of different organic contaminants in redox zones were different. Content of volatile hydroxybenzene and cyanide in sulfate reduction zone were relative high, and they were 0.005 and 0.019 μg/L, respectively. Heavy metal content, such as Cr, Pb, Ni, As, Cu, Cd, Zn and Mn were relative high in methanogenic zone, and they were25.11, 33.82, 29.93, 3.18, 2.3, 0.1, 283.1, 1 220 μg/L, respectively. Therefore, redox zones played an important role on the attenuation of pollutants.