厌氧-限氧SBR处理低C/N生活污水SNDPR启动及N_(2)O释放  

The characteristics of SNDPR and N_(2)O emission in anaerobic-oxygen limited SBR treating low C/N domestic sewage

作　　者：巩有奎 罗佩云[1] 孙洪伟 GONG Youkui;LUO Peiyun;SUN Hongwei(Department of Architecture Engineering,Yantai Vocational College,Yantai 264670,Shandong,China;School of Environmental and Material Engineering,Yantai University,Yantai 264005,Shandong,China)

机构地区：[1]烟台职业学院建筑工程系,山东烟台264670 [2]烟台大学环境与材料工程学院,山东烟台264005

出　　处：《化工学报》2021年第8期4381-4390,共10页CIESC Journal

基　　金：国家自然科学基金项目(51668031);烟台职业学院2020年校本科研项目(2020XBZD001)。

摘　　要：以厌氧-限氧方式运行序批式生物反应器(SBR),采用逐步降低进水碳氮比(C/N)方式驯化聚磷菌(PAOs)和聚糖菌(GAOs),启动了低C/N生活污水同步脱氮除磷过程(SNDPR),并考察了SNDPR内PAOs、GAOs间竞争关系及系统脱氮除磷性能过程N_(2)O释放特性。结果表明,C/N=7.0,SBR限氧段脱氮和除磷效率分别为83.5%和90%以上,N_(2)O产量为0.54 mg/L;C/N=3.0~3.5,脱氮和除磷效率分别降至60.1%和80.5%,N_(2)O产量达1.09 mg/L。SBR内不同反应阶段内源物质变化均表现出PAOs-GAOs共存特性。高C/N有利于微生物合成聚-β-羟基烷酸酯(PHA)并促进N_(2)O还原。C/N降低,SBR内污泥内源物质转化倾向于富集GAOs的降解特性。氨氧化菌(AOB)好氧反硝化过程及GAOs以PHA作为电子供体的内源反硝化过程促进了N_(2)O的释放。随C/N降低,SBR内污泥平均胞外聚合物(EPS)由43.4 mg/g VSS增至50.5 mg/g VSS,污泥容积指数(SVI)由99 ml/g增至127 ml/g。疏松型EPS(LB-EPS)内,蛋白质(PN)与多糖(PS)之比(PN/PS)随C/N增加而降低,污泥亲水性增加,不利于污泥脱水。By gradually reducing the carbon to nitrogen(C/N)ratio,the phosphorus accumulating organisms(PAOs)and glycogen accumulating organisms(GAOs)were acclimated in a sequencing batch with anaerobic-limited oxygen operation mode.The simultaneous nitrification-denitrification and phosphorus removal(SNDPR)process of low C/N ratio domestic wastewater was accomplished.The competition between PAOs and GAOs,as well as the N_(2)O release at different C/N ratio,was studied.The results showed that the simultaneous nitrification and denitrification(SND)nitrogen removal and phosphorus removal efficiency of SNDPR were 83.5%and over 90%respectively at the C/N ratio of 7.0.The N_(2)O emission was 0.54 mg/L.The SND and phosphorus removal efficiency decreased to 60.1%and 80.5%respectively at C/N ratio of 3.0-3.5.Meanwhile,the N_(2)O emission reached 1.09 mg/L and the N_(2)O yield was 7.68%.The decrease of PHA accumulation,coupled with the increase of denitrification by GAOs,resulted in the higher N_(2)O emission at the lower C/N ratio of domestic wastewater.The variation of endogenous substance in different stage of SBR showed that PAOs-GAOs coexisted at each C/N ratio.GAOs tended to be enriched in SNDPR with the decreasing of C/N ratio.The extracellular polymer(EPS)increased from 43.4 mg/g VSS to 50.5mg/g VSS and the sludge volume index(SVI)increased from 99 ml/g to 127 ml/g with the decrease of C/N ratio.In loose EPS(LB-EPS),the ratio of protein(PN)to polysaccharide(PS)(PN/PS)decreases as C/N increases,and the hydrophilicity of sludge increases,which is not conducive to sludge dewatering.

关 键 词：碳氮比 聚磷菌 聚糖菌 同步脱氮除磷 N_(2)O 

分 类 号：X703.1[环境科学与工程—环境工程]