人工湿地分散式污水处理系统的设计和运行

采用由预处理单元、水平潜流人工湿地单元、消毒单元和污泥干化单元组成的分散式污水处理系统对采油区生活点污水进行了处理和资源化利用。核心工艺单元水平潜流人工湿地单元的优化设计参数为:人工湿地宽20 m、长80 m,采用多段串联布置形式。分散式污水处理系统实际处理水量为92~136 m3/d,在5年的实际运行过程中,COD,BOD5,NH3-N,SS的平均去除率分别为75.9%,77.3%,96.0%,96.1%。处理后出水经消毒后的水质优于GB/T18920—2002《城市污水再生利用城市杂用水水质》标准中绿化用水的水质,可作为绿化灌溉用水回用;干化后的栅渣和污泥可作为绿化肥料使用,能实现污水的资源化利用和处理系统的零排放。

Design and Operation of Decentralized Wastewater Treatment System with Constructed Wetlands

A decentralized wastewater treatment system,composed of pretreatment unit,horizontal subsurface flow constructed wetlands unit,disinfection unit and sludge drying unit,was used to treat and recycle the domestic sewage in a resident site of oilfield. As the key treatment unit,several design parameters of the horizontal subsurface flow constructed wetlands were optimized and the optimum design parameters are as follows：20 m of width,80 m of length,and with multi-step series arrangement. According to the data statistics of 5 years operation,the actual quantity of sewage treatment is 92-136 m³/d,and the average removal rates of COD,BOD₅,NH₃-N and SS are 75.9%,77.3%,96.0% and 96.1%,respectively. The quality of the disinfected effluent is better than the requirement of GB/T18920-2002 for greening water from urban sewage reuse,so it can be reused as irrigation water for virescence;The dried screenings and sludge can be used as green fertilizer. Therefore,the resource utilization of the domestic sewage and zero emission of the treatment system are achieved.