低温城市污水厂改型百乐克工艺脱氮除磷改造应用

Application of Modified BIOLAK Process for Improvement of Nitrogen and Phosphorus Removal in Low Temperature Municipal Wastewater Treatment Plants

河北某污水处理厂主体处理工艺采用改型百乐克(BIOLAK)工艺,由于冬季时水温过低(6℃左右),出水TN、TP指标难以稳定达到一级A排放标准,急需对污水厂进行工艺改造。为了解决污水厂冬季低温运行过程中出现的常见的TN波动问题,小试试验采用SBR工艺,模拟污水处理厂现有工艺的实际运行参数,通过试验不同的停留时间(HRT),投放不同比例的MBBR生物填料,逐一验证污水厂运行时出水总氮波动的影响因素,重点分析其运行效果,为后续工艺改造确定合理参数提供参考。经试验研究,在缺氧池内投加25%的MBBR填料时,出水TN可满足出水标准要求。根据试验结果,污水厂改造主工艺采用“缺氧池增加MBBR填料+新建高效沉淀池”,改造后的污水厂经过近两年的实际运行,出水水质可稳定达到国家要求排放标准的一级A标准,说明改造的工艺流程和选取的工艺参数较为合理。

Main treatment process of a wastewater treatment plant in Hebei Province adopts modified BIOLAK process.Because water temperature there is too low(about 6℃)in winter,i.e.,TN and TP of the effluent to be difficult to reach the Level A standard,so it is urgent to renovate the process of relevant wastewater treatment plant.In order to solve the common problem of TN fluctuation in the process of low temperature operation in winter,SBR process is used in the pilot test to simulate actual operation parameters of existing process in relevant wastewater treatment plant.Through the tests with different retention time and different proportion of MBBR biological filler,the influencing factors of total nitrogen fluctuation in effluent are verified one by one,and operation effect is analyzed emphatically.It provides a reference for determining reasonable parameters for subsequent process renovation.Results show that the effluent TN can meet the requirements of effluent standard when 25% MBBR filler is added in the anoxic tank.According to test results,the main process of the reconstruction of relevant wastewater treatment plant adopts"anoxic tank adding MBBR filler+new high-efficiency sedimentation tank".After nearly two years of actual operation,the effluent quality of relevant reconstructed wastewater treatment plant can stably meet the Level A standard of the national discharge standard,which indicates that the selection of process flow and process parameters is reasonable.