A_2_O_曝气生物滤池工艺反硝化除磷_陈永志

第62卷第3期化工学报Vol.62No.32011年3月CIESCJournalMarch2011研究论文A2/O-曝气生物滤池工艺反硝化除磷陈永志,彭永臻,王建华,顾升波(北京工业大学北京市水质科学与水环境恢复工程重点实验室,北京100124)摘要:以低C/N生活污水为研究对象,考察了A2/O-曝气生物滤池生化系统的脱氮除磷特性。通过缩短A2/O的泥龄,把硝化过程从A2/O中分离出去,让曝气生物滤池实现硝化;A2/O在短泥龄条件下运行,有利于除磷及反硝化,曝气生物滤池在长泥龄条件下运行,有利于硝化效果的稳定和氨氮的彻底去除;曝气生物滤池回流来的硝化液为A2/O的缺氧区提供了充足的电子受体,为反硝化除磷提供了必要条件。试验结果表明,在HRT为7.5h,泥龄为15d,硝化液回流比为400%的条件下,平均进水COD、NH+4-N、TN和TP浓度分别为376、67.9、72.9、6.1mg·L-1时,系统出水COD、NH+4-N、TN和TP浓度分别为42、0.86、9.6、0.1mg·L-1,实现了COD和氮磷的同步深度去除;硝化液回流比为200%和400%时,反硝化除磷量分别为1.49、1.64gTP·(gMLVSS)-1·d-1;序批试验表明,反硝化聚磷菌占聚磷菌的比值为68.2%;泥龄增加,TP去除率下降。关键词:A2/O-曝气生物滤池工艺;反硝化除磷;深度脱氮除磷;硝化液回流比;泥龄;低C/N中图分类号:X703.1文献标志码:A文章编号:0438-1157(2011)03-0797-08DenitrifyingphosphorusremovalinA2/O-BAFprocessCHENYongzhi,PENGYongzhen,WANGJianhua,GUShengbo(KeyLaboratoryofBeijingforWaterQualityScienceandWaterEnvironmentalRecoveryEngineering,BeijingUniversityofTechnology,Beijing100124,China)Abstract:Removalbehaviorsofbiologicalphosphorus(P)andnitrogen(N)inrealdomesticsewagewithlowC/Nratiowerestudiedinalaboratory-scaledanaerobic/anoxic/oxic(A2/O)-biologicalaeratedfilter(BAF)combinedsystem.Inordertoimproveremovalefficiencyofthecombinedsystem,shortsludgeretentiontime(SRT)wasappliedinA2/O,whichwasfavorableforPremovalanddenitrification,whilelongerSRTusedinbiologicalaeratedfilter(BAF),whichwasfavorableforpolyphosphate-accumulatingorganisms(PAOs)andfornitrificationtoremovetheammoniumnitrogen.TherecycledliquidinvolvingnitratefromBAFprovidedelectronacceptorenoughfortheanoxic-zonesofA2/Oandnecessaryconditionforde-phosphorusbydenitrifying.ExperimentalresultsshowedthatwiththeseoperationsinthiscombinedsystemCOD,NandPcouldberemovedsimultaneously.AtconditionsofHRT7.5h,SRT15d,therecyclingratioofliquid400%,theconcentrationsofCOD,ammoniumnitrogen,totalnitrogen(TN)andtotalphosphorus(TP)couldbereducedfromataveragevaluesof376,67.9,72.9and6.1mg·L-1intherawwastewaterto42,0.86,9.6and0.1mg·L-1intheeffluent,respectively.Therateofphosphorus2010-05-24收到初稿,2010-09-03收到修改稿。联系人:彭永臻。第一作者:陈永志(1969—),男,博士研究生。基金项目:国家“十一