猪场废水厌氧生物处理FAN抑制及其调控对策的研究-唐崇俭2

第22卷第4期高校化学工程学报No.4Vol.222008年8月JournalofChemicalEngineeringofChineseUniversitiesAug.2008文章编号：1003-9015(2008)04-0697-06猪场废水厌氧生物处理FAN抑制及其调控对策的研究唐崇俭1,郑平1,金仁村1,胡宝兰1,余燚1,陈建伟1,黄武2(1.浙江大学环境工程系,浙江杭州310029;2.浙江省沼气太阳能科学研究所,浙江杭州310012)摘要：通过稀释降低废水浓度和采用磷酸铵镁沉淀法除铵预处理，研究了猪场废水厌氧生物处理的运行性能。UASB(upflowanaerobicsludgeblanket)反应器的运行结果表明，游离氨氮(freeammonianitrogen,FAN)是猪场废水厌氧生物处理的重要障碍因子，其临界抑制浓度为100~120mgN⋅L−1；猪场废水FAN浓度为140~230mgN⋅L−1，高于临界FAN抑制浓度；对猪场废水直接进行厌氧生物处理，COD(chemicaloxygendemand)去除率为8.1％~15.6％，容积产气率为0.32L⋅L−1⋅d−1，反应液挥发性脂肪酸(volatilefattyacid,VFA)浓度高达2000mg⋅L−1，表现出典型的运行障碍；FAN超过临界抑制浓度后，可触发对厌氧生物处理过程的抑制，致使反应液VFA高于2000mg⋅L−1，进而加剧抑制效应，引起反应器功能崩溃。将pH控制在适宜厌氧生物处理的下限区间，稀释进水将FAN降低到临界抑制浓度以下，以及采用磷酸铵镁沉淀法进行除铵预处理，均可缓解猪场废水厌氧生物处理的运行障碍，COD去除率升至60.0%~72.2%，VFA去除率高达90.0%，容积产气率升高至1.50~1.92L⋅L−1⋅d−1。关键词：猪场废水；厌氧生物处理；游离氨；调控对策中图分类号：X703文献标识码：AInhibitionofAnaerobicDigestionofSwineWastewaterCausedbyFreeAmmoniaNitrogenanditsControlStrategiesTANGChong-jian1,ZHENGPing1,JINRen-cun1,HUBao-lan1,YUYi1,CHENJian-wei1,HUANGWu2(1.DepartmentofEnvironmentalEngineering,ZhejiangUniversity,Hangzhou310029,China;2.ResearchCenterofBiogasandSolarEnergyofZhejiangProvince,Hangzhou310012,China)Abstract:Throughdilutingthetreatedswinewastewaterpreviouslyandpretreatingitbymagnesiumammoniumphosphateprecipitation,theperformanceofanaerobictreatmentprocessforswinewastewaterwasinvestigatedinaUASB(upflowanaerobicsludgeblanket)reactor.Theexperimentalresultsshowthatthethresholdinhibitionconcentrationoffreeammonianitrogen(FAN)fortheanaerobicdigestionis100~120mgN⋅L−1.SincetheFANconcentrationofswinewastewatertested(140~230mgN⋅L−1)ishigherthantheFANthresholdinhibitionconcentration,typicalprocessdysfunctionwilloccuriftheanaerobictreatmentoftheswinewastewaterisconducteddirectly,duringwhichthechemicaloxygendemand(COD)removalefficiencyandbiogasproductionrateareonly8.1%~15.6%and0.32L⋅L−1⋅d−1,respectively;thevolatilefattyacid(VFA)concentrationintheeffluentis200mg⋅L−1ormore.ItwasbelievedthatwhenFANconcentrationisbeyonditsthresholdinhibitionvalue,theanaerob