污水处理厂优于一级A提标改造工程设计案例——以深圳某污水处理厂为例

深圳市某污水处理厂设计规模为20万m³/d,提标改造工程需将出水水质由《城镇污水处理厂污染物排放标准》(GB18918—2002)中的一级B标准提升至《地表水环境质量标准》(GB 3838—2002)中的"准Ⅳ类水标准"。提标改造工程对现有生物反应池处理能力进行充分复核,根据复核结果确定了MBBR的改造方向以提高氮类污染物的去除效果。同时,增设磁混凝沉淀池+超滤膜的组合深度处理工艺进一步去除SS和TP。本工程总投资为2.84亿元,提标改造后污水厂新增单位经营成本0.57元/m³。本工程主体部分于2018年建成通水,各项出水水质指标稳定达标,重点关注指标SS、TN、NH₃-N、TP的去除率分别由改造前的96%、52%、89%、89%提高至99%、75%、98%、98%。本项目采用的设计思路和设计参数可供同类污水处理厂提标改造工程参考。

Engineering Design and Discussion of a WWTP Better than First Grade A Standard Upgra-ding and Reconstruction Project in Shenzhen

Design scale of a wastewater treatment plant in Shenzhen is 200000 m³/d.The effluent quality requirement has been raised from the first grade B standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918—2002)to the quasi-IV water standard of Surface Water Environmental Quality Standard(GB 3838—2002).The current biological reactor’s capacity for the removal of nitrogen pollutants is not enough,then MBBR is selected as the main enhanced treatment process for the UCT process,and magnetic coagulation sedimentation&ultrafiltration membrane process are added as the advanced treatment section for the secondary effluent.The total investment of the project is 284 million yuan,and operating cost increased by 0.57 yuan/m³.The main part of the project has been completed in 2018,and effluent of the plant could meet the requirements of the quasi-IV standard steadily,the removal efficiency of SS,TN,NH₃-N,TP increased from 96%,52%,89%,89%to 99%、75%、98%、98%.The concept and selected parameters of this project could be used as reference for the upgrading and reconstruction of similar WWTPs.