某工业废水处理厂提标改造工程设计与运行效果

浙江某工业废水污水厂,原设计处理规模为3万m3/d,出水COD、SS执行二级标准,NH3-N、TN和TP执行一级B标准。2018年进行升级改造,要求处理水量提高至4万m3/d,出水全部执行一级A标准。改造中,核心生化段采用MBBR工艺,好氧区投加悬浮载体强化生物脱氮除磷,三级处理增加磁混凝澄清池强化TP的去除。改造后出水CODCr、BOD5、NH3-N、TP、TN均值分别为(30.52±5.73)、(1.92±1.40)、(0.90±0.92)、(0.09±0.075)、(8.26±2.55)mg/L,除COD外,其余指标均可达到准IV水质。改造前单位水处理费用为0.491元/m3,改造后单位水处理费用为0.584元/m3,单位水处理成本增加0.093元/m3。对系统中的微生物进行高通量测序,结果显示,悬浮载体中硝化菌丰度平均为5.62%,反硝化菌丰度为3.81%,悬浮载体中含有69.8%的硝化菌,反硝化菌的存在证明悬浮载体上的SND过程。

Design and Operation Performance of Upgrading and Reconstruction Project for an Industrial Wastewater Treatment Plant

Designed capacity of an industrial wastewater treatment plant(WWTP)in ZheJiang Province is 30000 m3/d,in which COD and SS of effluent executes second grade criteria,while NH3-N,TN and TP executes first grade B criteria.The WWTP is required to upgrade and reconstruct in 2018,and the capacity is increased to 40000 m3/d,the effluent should meet first grade A criteria.In the project,MBBR process is adopted in core biochemical section,suspension carrier is added to aerobic zone to enhance biological nitrogen and phosphorus removal,and magnetic coagulation clarification tank is added for further treatment.After upgrading and reconstruction,mean value of CODCr,BOD5,NH3-N,TP and TN of effluent is(30.52±5.73),(1.92±1.40),(0.90±0.92),(0.09±0.075)mg/L and(8.26±2.55)mg/L,respectively.Other indexes can meet ClassⅣof environment quality criteria except COD.Before upgrading and reconstruction,the cost of water treatment is 0.491 yuan/m3.After that,the cost of water treatment is 0.584 yuan/m3,increased by 0.093 yuan/m3.High-throughput sequencing of microorganisms in the system shows that the abundance of nitrifying bacteria in suspended carrier is 5.62%,which containing 69.8%nitrifying bacteria,and denitrifying bacteria is 3.81%,proving SND process in suspended carriers.