污水集中处理厂污水中金属(重金属)的分布

系统地建立集中污水处理装置是环境管理和污染治理的发展方向之一，在工业发达国家已相当普及，本文分析了美国和加拿大污水集中处理厂原污水和常用治理流程各工序中金属（重金属）的分布情况。结果表明，由于地理，气候，人口，特别是工业分布的影响，原污水中金属含量会有较大变化，因为变化范围大且超过排放标准2－10倍（按均值计），在设计和评价时应予化重点考虑的几种金属为：Cd,Cu,Cr,Pb,Ni和Zn，经典型的沉淀－活性污泥工艺处理后，金属除去率大于80％，可以满足排放要求。

Distribution of Metals (Heavy Metals) in Centralized Sewage Treatment Plant

Establishment of centralized sewage treatment plant is one of development direction in environment management and pollution treatment.It is widely popularized in developed country.The distribution of metals in sewage at entrance and different sections of centralized sewage treatment plant in USA and in Canada was analyzed in the paper.The results indicated that content of metals in sewage at entrance can be influenced by geography,weather,population,especially industrial plants.Because of greater change and access of discharge standard,Cd,Cu,Cr,Pb,Ni and Zn should be pay more attention in evaluation and design.With typical precipitation active sludge process,elimination ratio of the metals is over 80% and discharge standard can be met.