硝化生物膜系统对低温的适应特性:MBBR和IFAS  

Adaptability of Nitrifying Biofilm Systems to Low Temperature:MBBR and IFAS

作　　者：李韧 于莉芳[1,3] 张兴秀 戴子承 滑思思 彭党聪[1] LI Ren;YU Li-fang;ZHANG Xing-xiu;DAI Zi-cheng;HUA Si-si;PENG Dang-cong(School of Municipal and Environmental Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;Key Laboratory of Northwest Water Resource,Environment and Ecology,Ministry of Education,Xi'an University of Architecture and Technology,Xi'an 710055,China;Shaanxi Key Laboratory of Environmental Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学环境与市政工程学院,西安710055 [2]西安建筑科技大学西北水资源与环境生态教育部重点实验室,西安710055 [3]西安建筑科技大学陕西省环境工程重点实验室,西安710055

出　　处：《环境科学》2020年第8期3691-3698,共8页Environmental Science

基　　金：陕西省自然科学基金项目(2020JM-474)。

摘　　要：为探明硝化生物膜系统对低温的适应特性,在不同温度(20、15和10℃)下长期运行移动床生物膜反应器(MBBR)和生物膜-活性污泥复合工艺(IFAS)并考察温度降低对其硝化性能、生物膜特性及群落结构的影响,以期为生物膜系统在污水处理行业的应用提供理论依据.结果表明,当温度降低至10℃时,MBBR和IFAS的氨氮去除率分别为(90.88±5.73)%和(99.79±0.31)%,表明IFAS比MBBR具有更好的低温适应性.这是由于低温导致胞外聚合物(EPS)含量的增加,进而促使生物膜厚度及干重不断升高,而相同负荷下的MBBR生物膜更容易堵塞,从而影响传质.活性测定结果表明,尽管IFAS中活性污泥的硝化贡献率始终占主导地位,但随着温度降低,生物膜的氨氧化贡献率从30.72%逐渐上升至39.85%,起到了强化硝化的作用.qPCR结果显示,温度的降低使生物膜中硝化细胞拷贝数上升,其与低温下生物膜厚度的增加一定程度上弥补了硝化活性的衰减,从而体现了生物膜对低温较强的适应性.The long-term effects of a decreasing temperature on the nitrification performance,biofilm characteristics,and nitrifier community in a moving-bed biofilm reactor(MBBR)and integrated fixed-film activated sludge(IFAS)system were investigated at various temperatures(20,15,and 10℃)to explore the adaptability of nitrifying biofilm systems to low temperatures.During the experiment,the extracellular polymeric substances(EPS)in the biofilms increased with decreasing temperature,which resulted in an increased biofilm mass and thickness.As there was only a biofilm phase in the MBBR to remove ammonia,the part of the carriers in the MBBR at 10℃became plugged,which partially led to a deterioration in the effluent water quality.This indicated that the IFAS system was more adaptable to low temperatures than was the MBBR.Meanwhile,the results for the nitrifier activities showed that,although the nitrification contribution rate of the suspended phase in the IFAS system always dominated during the experiment,that of the fixed phase with regards to the ammonia uptake rate(AUR)gradually increased from 30.72%at 20℃to 39.85%at 10℃.This indicated that the biofilm played an enhanced role in nitrification in the IFAS system.Moreover,the qPCR results revealed that the nitrifier copies of the number of biofilms increased slightly with decreased temperature,and coincided with an increase in biomass,which partially compensated for the decreased nitrification activity.These findings provide a theoretical basis for the application of the biofilm systems to wastewater treatment.

关 键 词：低温 移动床生物膜反应器(MBBR) 生物膜-活性污泥复合工艺(IFAS) 生物膜特性 定量PCR(qPCR) 

分 类 号：X703[环境科学与工程—环境工程]