中国城市污泥重金属和养分的区域特性及变化

Regional characteristics and trend of heavy metals and nutrients of sewage sludge in China

通过对我国111个城市共193个污水处理厂污泥的重金属及有机质和氮磷钾含量进行了分析和统计,并与2003年的数据进行了对比,同时也按照南北和东中西的区域划分进行了区域统计.结果表明,相对于2003年,Zn、Pb的平均含量有所降低,而Cu、Cr、Ni、As、Hg的平均含量则有所增加,Cd的含量大幅增加;有机质、氮、磷含量均略有增加,钾的含量变化不大.北方污泥中Zn、Cu、Cd、Cr、Ni的含量要低于南方污泥,Pb、As和Hg的含量则远大于南方污泥.Zn、Cu、Cd、Pb、Hg、Ni的含量由东向西逐渐降低;Cr的含量则为中部最高;As的含量由东向西逐渐升高.北方污泥的有机质、钾含量都要大于南方污泥,而氮、磷含量则小于南方污泥.污泥的有机质、氮由东向西逐渐升高,磷的含量则逐渐降低,中西部污泥的钾含量大于东部污泥.

The sewage sludge samples from 193 wastewater treatment plants in 111 cities were analyzed and the data was counted.Results were compared with data in 2003,and were analyzed in accordance with distribution of north-south and east-west in China.Results showed that,in comparison with 2003,average contents of Zn,Pb,Cu,Cr,Ni,As,Hg of sludge decreased,and content of Cd increased.Contents of organic matter,nitrogen and phosphorous slightly increased,while potassium changed little.Average contents of Zn,Cu,Cd,Cr and Ni of northern sludge were smaller than southern sludge,contents of Pb,As and Hg were higher than southern sludge.Contents of Zn,Cu,Cd,Pb,Hg and Ni decreased from east to west,and contents of As increased from east to west,and content of Cr of middle sludge was highest.Contents of organic matter and potassium of northern sludge was higher than southern sludge,and contents of nitrogen and phosphorous were smaller than southern sludge.Contents of organic matter and nitrogen increased from east to west,and content of phosphorous decreased,and potassium contents of middle sludge and western sludge were higher eastern sludge.