阿维菌素废水工业化UASB颗粒污泥产甲烷菌群分析

Analysis of Methanogenic Community of Anaerobic Granular Sludge in a Full-scale UASB Treating Avermectin Wastewater

产甲烷菌群是厌氧颗粒污泥的重要功能菌群,采用荧光原位杂交(fluorescencein situhybridization,FISH)技术对阿维菌素废水处理工业化UASB颗粒污泥产甲烷菌群进行分析.结果表明,不同形成阶段(不同粒径)颗粒污泥表面和内部剖面,一般产甲烷菌(methanogens)、产甲烷杆菌(Methanobacteriales)和产甲烷八叠球菌(Methanosarcinales)的分布形态相同,但相对丰度存在差异.颗粒污泥内部剖面产甲烷菌群相对丰度大于表面;产甲烷杆菌相对丰度大于产甲烷八叠球菌;颗粒污泥表面和内部剖面产甲烷菌群相对丰度范围为(25.50±8.63)%^(48.67±8.87)%;1.0~2.0 mm粒径颗粒污泥产甲烷菌群相对丰度最大,内部剖面和表面一般产甲烷菌的相对丰度分别为(47.08±8.26)%和(48.67±8.87)%.废水阿维菌素残留可能对产甲烷菌群具有抑制作用.不同粒径颗粒污泥最大比产甲烷活性范围为1.311~1.562 g/(g.d),变化趋势与COD去除率变化趋势相同,而且与产甲烷菌群相对丰度变化趋势一致,表明颗粒污泥生物活性与产甲烷菌群密切相关.

Methanogens is considered to be important functional microbial population in anaerobic granular sludge.Fluorescence in situ hybridization was used to analyze methanogens of anaerobic granular sludge in a full-scale UASB treating avermectin wastewater.The results indicated that the distribution forms of methanogens,Methanobacteriales and Methanosarcinales were identical on the surface and inner face of granular sludge samples in different formation stages（with different diameters）,although the relative abundances of these methanogens were different.The relative abundances of methanogens on the inner face were larger than these on the surface of granular sludge samples.The relative abundances of Methanobacteriales were larger than these of Methanosarcinales.The relative abundances of methanogens in all granular sludge samples ranged from（25.50±8.63）% to（48.67±8.87）%.The maximum relative abundances of methanogens were obtained in mature granular sludge with diameter of 1.0-2.0 mm,（47.08±8.26）% on the surface and（48.67±8.87）% on the inner face,respectively.The avermectin residue in wastewater showed possible inhibition effect on methanogens.The maximum specific methanogenic activities of granular sludge samples ranged from 1.311 to 1.562 g/（g·d）,varying as same as COD removal ratios and relative abundances of methanogens,implying the strong correlation of methanogens with bioactivity of granular sludge.