摘要
针对养猪废水采用传统工艺经厌氧发酵处理后,形成高氨氮低碳氮比沼液,导致脱氮效果差、工艺流程复杂、启动周期较长等问题.本研究以异养硝化-好氧反硝化(HN-AD)菌为生物强化剂,以PAN活性炭纤维作为填料的生物接触氧化池(BCO)为生物膜反应器,形成生物强化BCO工艺处理猪场沼液.前期污泥驯化阶段发现,NH_4^+-N浓度高于500 mg·L^(-1)时,污染物去除率明显降低,经HN-AD菌剂生物强化后,耐受NH_4^+-N浓度可高于600 mg·L^(-1)且能保持污染物的高效去除.采用HN-AD生物强化的BCO工艺处理真实猪场沼液,对NH4+-N、TN和COD的平均去除率分别为86. 9%、70. 5%和74. 4%,分别高于传统处理工艺的57. 6%、50. 3%和50. 0%,出水浓度均低于相关污染物排放标准.采用高通量测序技术研究了功能菌富集过程中微生物群落结构的变化规律,结果表明,生物膜内属于HN-AD菌的优势菌由Alcaligenes这一种菌属增加为生物强化后的Diaphorobacter、Acinetobacter和Thauera等多种菌属,且Acinetobacter菌属的相对丰度明显高于接种菌剂.扫描电子显微镜结果也进一步证实了生物强化的存在,紧密附着在填料上的生物膜层表面富集了以杆状和球状为主的HN-AD功能菌.
The conventional pretreatment process for swine wastewater is anaerobic fermentation.This process leads to the formation of high ammonia nitrogen,low carbon,and piggery biogas slurry,which usually results in poor denitrification effect,complicated process flow,and long startup period for the subsequent treatment process.In this study,a novel biological enhanced Biological Contact Oxidation(BCO)process using HN-AD bacteria as microbial inoculants,and PAN activated carbon fiber filler as biofilm carrier was proposed for the treatment of piggery biogas slurry.In the early stage of sludge acclimation,it was found that when NH4+-N concentration was higher than 500 mg·L-1,the nitrification and COD removal in BCO was severely inhibited.When the BCO was enhanced by HN-AD bacteria,however,the tolerance concentration of NH4+-N for bacteria in BCO could reach 600 mg·L-1 and the removal efficiency of NH4+-N,COD,and TN could still remain at a high level.The bio-enhanced BCO process was used to treat the piggery biogas slurry.The average removal rates of NH4+-N,TN,and COD were 86.9%,70.5%,and 74.4%,respectively,which were higher than the 57.6%,50.3%,and 50.0%of the traditional treatment process.The concentration of the pollutants mentioned above in the effluent was below the relevant discharge standards.The changes in the microbial community structure during the enrichment process of functional bacteria were studied by high-throughput sequencing technique.The results showed that the dominant bacteria belonging to HN-AD in the biofilm during the sludge acclimation process was Alcaligenes.After the addition of the HN-AD agent,however,the dominant bacteria were Diaphorobacter,Acinetobacter,and Thauer,and the relative abundance of Acinetobacter was much higher than that in the microbial inoculants.The results of scanning electron microscopy further confirmed the existence of bio-enhancement.The surface of the biofilm layer tightly attached to the filler was enriched with rod-like and globular HN-AD functional bacteria.
作者
刘向阳
张千
吴恒
李宸
唐健泓
封丽
肖芃颖
赵天涛
LIU Xiang-yang;ZHANG Qian;WU Heng;LI Chen;TANG Jian-hong;FENG Li;XIAO Peng-ying;ZHAO Tian-tao(School of Chemical Engineering,Chongqing University of Technology,Chongqing 400054,China;Chongqing Academy of Environmental Science,Chongqing 401147,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2019年第5期2349-2356,共8页
Environmental Science
基金
国家自然科学基金项目(51708077)
重庆市社会事业与民生保障科技创新专项(cstc2018jscx-msybX0134)
