低氧环境anammox工艺运行性能及功能菌群结构研究

Operation Performance and Functional Bacterial Structure Characteristics of Anammox Process under Low Oxygen Environment

为了研究低溶解氧(DO)条件下厌氧氨氧化(anammox)工艺的运行性能、颗粒污泥特征及功能菌群结构特征,实验以模拟废水为处理对象,构建了实验室规模的上流式厌氧氨氧化污泥反应器。实验结果表明,反应器能够在近两个月的运行过程中保持稳定运行,NH_(4)^(+)-N、NO_(2)^(-)-N和TN的平均去除率分别为(93.11±4.13)%、(98.88±1.18)%和(95.98±10.6)%。胞外聚合物(EPS)的蛋白/多糖为1.26,anammox污泥颗粒化程度较高,粒径大于1 mm的颗粒污泥占全部污泥的为61%。污泥比anammox活性为4.34 mg NH_(4)^(+)-N/(gVSS·h)、6.55 mg NO_(2)^(-)-N/(gVSS·h)、9.78 mg TN/(gVSS·h)。菌群分析结果表明,颗粒污泥优势门为变形菌门(Proteobacteria)(24.25%),浮霉菌门(Planctomycetes)(19.61%)和绿弯菌门(Chloroflexi)(10.48%),优势属为Candidatus Brocadia(12.56%)、Chloroflexinoname(4.64%)和Bacterianoname(2.7%)。其中,Candidatus Brocadia为优势Anammox菌,承担anammox反应。低DO条件对anammox反应器运行性能的影响较低,但改变了anammox反应化学计量比且在颗粒污泥中观察到了氨氧化菌亚硝化单胞菌属(Nitrosomonas)(0.66%)。

In order to study the operation performance,granular sludge and functional bacterial structure characteristics in anaerobic ammonia oxidation(anammox)process under low dissolved oxygen(DO)conditions,a lab-scale up-flow anammox sludge reactor was constructed with synthetic wastewater as influent.Experimental results showed that the reactor was stably operated within nearly two months,and the average NH_(4)^(+)-N,NO_(2)^(-)-N and TN removal efficiencies were(93.11±4.13%),(98.88±1.18%)and(95.98±10.6%),respectively.The PN/PS of 1.26 in extracellular polymer(EPS)suggested a higher granular degree of anammox sludge.There were 61%of thetotal sludge granular sludge with granular size greater than 1mm.The specific anammox activity of anammox sludge were 4.34 mg NH_(4)^(+)-N/gVSS·h,6.55 mg NO_(2)^(-)-N/gVSS·h and 9.78 mg TN/gVSS·h.Bacterial analysis showed that Proteobacteria(24.25%),Planctomycetes(19.61%)and Chloroflexi(10.48%)were the dominant phyla in granular sludge.The dominant genera were Candidatus Brocadia(12.56%),Chloroflexinoname(4.64%)and Bacterianoname(2.7%).In anammox system,Candidatus Brocadia,mainly contribute to the anammox action,was the dominant Anammox genus.The operation performance of anammox reactor was not obviously affected by lower DO conditions.However,the reaction stoichiometry ratio of anammox was changed and the ammonia oxidation bacteria(AOB)Nitrosomonas(0.66%)was observed in granular sludge.