大型餐厨垃圾处理厂沼液处理工艺的运行效果分析  

Investigation on purification efficiency of anaerobically digested slurry of restaurant food wastes from a large-scale treatment plant

作　　者：邬振江 颜成[1,2] 杨德坤 梁剑茹 王电站[1] 周立祥[1] WU Zhenjiang;YAN Cheng;YANG Dekun;LIANG Jianru;WANG Dianzhan;ZHOU Lixiang(College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China;Nanjing BACT Environmental Solutions Co. Ltd.,Nanjing 211505,China)

机构地区：[1]南京农业大学资源与环境科学学院,江苏南京210095 [2]南京贝克特环保科技有限公司,江苏南京211505

出　　处：《南京农业大学学报》2020年第3期485-491,共7页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(21637003)。

摘　　要：[目的]本文通过现场调研代表性餐厨垃圾处理厂沼液处理工艺的生化效果,为已建成或待建的餐厨垃圾处理厂沼液达标处理工艺的选择或优化提供技术支撑。[方法]以河北省某大型餐厨垃圾处理厂沼液净化工艺“二相固液分离→气浮→混凝沉淀→生化处理→膜处理”为对象,通过测定该系统各单元出水水质指标,分析现行处理工艺存在的主要问题及其原因,在此基础上提出工艺改进建议。[结果]该餐厨沼液是一种高悬浮固体(SS)(26400 mg·L^-1)、高化学需氧量(COD)(29440 mg·L^-1)、高氨氮(3512 mg·L^-1)、高磷(433 mg·L^-1)和高盐分(14100 mg·L^-1)的有机废水,由于其高浓度的污染负荷(特别是SS与NH+4-N)使现行工艺各单元对污染物(NH+4-N、TN、COD)的消减效果均很差,经过常规物化与生化处理后,NH+4-N、COD、TN、总磷(TP)和SS累积去除率分别为74.5%、89.5%、67.7%、97.7%和97.1%,其最终出水含量分别是895、3100、1246、9.89和760 mg·L^-1,分别是设计出水标准的29.8、10.3、17.8、2.0和3.3倍,色度高达200(呈红褐色)。[结论]该工艺因生化单元内微生物活性极低甚至丧失活性,基本没有发挥正常降解COD和脱氮除磷的作用。SS和氨氮等去除不理想导致生化池进水污染负荷较高,是生化效果差的主要原因。为提高现行工艺特别是生化单元的净化效果,需彻底去除进水SS和大幅降低NH+4-N浓度,适当扩大生化池容积,提高沼液的可生化性,恢复生化池菌密度及活性。[Objectives]In the study,a typical restaurant food waste(RFW)treatment plant was elaborately investigated with focus on the purification effectiveness of anaerobic digestate.The outcome of this study is conducive to developing or optimizing treatment process of digestate for RFW treatment plant.[Methods]We investigated the purification processes(solid-liquid separation→air flotation→coagulating and sedimentation→biochemical treatment→membrane treatment)of anaerobically digested slurry treatment system in a RFW treatment plant in Hebei Province,and suggested the improvement of processes based on the determination of water quality indexes of the effluent at different biochemical treatment stages.[Results]The anaerobically digested slurry was an organic wastewater with high concentration of SS(26400 mg·L^-1),COD(29440 mg·L^-1),NH+4-N(3512 mg·L^-1),TP(433 mg·L^-1),and salinity(14100 mg·L^-1).Lower removal effectiveness of pollutants(NH+4-N,TN,and COD)in the present treatment system were mainly caused by high concentration of pollution load(especially SS and NH+4-N)in the influent for biochemical treatment system.It was found that the final effluent after biochemical treatment still contained 895 mg·L^-1 NH+4-N,3100 mg·L^-1 COD,1246 mg·L^-1 TN,9.89 mg·L^-1 TP and 760 mg·L^-1 SS and with cumulative removal rate of 74.5%,89.5%,67.7%,97.7%and 97.1%,which were 29.8,10.3,17.8,2.0 and 3.3 times than those of the related designed discharge standards,respectively.The chroma was as high as 200(reddish brown).[Conclusions]The microorganisms with extremely low activity or even inactivation in biochemical pools didn’t play a role in effectively removing COD,N and P.In order to improve the purification efficiency of biochemical treatment,it’s necessary to thoroughly remove the SS and greatly reduce NH+4-N concentration of influent prior to biochemical treatment.In addition,appropriately expanding the volume of the biochemical pools,enhancing the biodegradability of anaerobically digested slurry,and increasing

关 键 词：餐厨沼液 生化处理 效果 原因分析 改进措施 

分 类 号：X703[环境科学与工程—环境工程]