基于提标升级改造的CAST工艺优化研究

利用CAST反应器处理生活污水,通过改变曝气时间、进水过程中曝气频率、气流速度,对比各参数条件下的出水水质,研究各参数对污染物去除的影响,探索它们与污染物去除之间的相关性,研究结果表明,试验条件下CAST工艺的最优工况为:进水时间40 min,进水过程中每5 min曝气一次,曝气量1.2 m3/h,曝气3 h,出水COD、氨氮和总磷达GB 18918-2002一级A标。且体系中DO与ORP的变化与污染物的去除也存在一定的相关性,两者随时间变化的转折点能用于指示氨氮达标的时间点。

OPTIMIZING THE CYCLIC ACTIVATED SLUDGE TECHNOLOGY(CAST) TO UPGRADING THE NUTRIENT REMOVAL EFFICIENCY OF CAST

Treated sewage in a CAST reactor to compare the effluent qualitybychanging the three parameters-the aeration time,aeration frequency at the filling period and the air current velocity,determined the best operation condition,researched the influence of those parameters to the nutrient removal,and explored the internal relationship between those parameters and the nutrient removal.The pilot study indicated that the optimal operation condition was like this: filling the sewage filled in the reactor within 40 min,aerating every 5 minutes at the filling period,setting the air velocity as 1.2 m3/h,aerating 3 h.At that condition,COD,NH3-N and TP of the effluent can reach the first class standard of discharge standard of pollutants for Chinese municipal wastewater treatment plant.Furthermore,the DO and ORP were related to the nutrient removal in a certain extant,and the turning point with time of the two directed that NH3-N had reached the limit of discharge.