水解酸化对好氧颗粒污泥形成及脱氮除磷的影响

摘要

In order to testify the impact of hydrolysis and acidification on the formation of aerobic granular sludge (AGS) and its performance of nitrogen and phosphorus removal, a two-stage system (HUSB(R1)+SBR(R2)) and a one-stage system (SBR(R3)) were set up for comparison of their performance on AGS cultivation on the basis of different substrates. The results showed that both the two-stage system and one-stage system could achieve AGS with dense structure and good settling performance. Granules with average diameters of>1.0-1.6 mm were found in R2 on the 13thday after inoculation,while flocculent sludge was dominant in R3.Granules in R2 grew to 1.0-2.0 mm after maturing and granules in R3 at last distributed between 1.0 and 1.6 mm. The removal of CODCrand NH3-N in both reactors almost reached 100% and the TN and TP removal in R2 were 88.5% and 72.8% respectively, which outperformed those values of 67.2% for TN and 60.1% for TP in R3. The best effluent quality achieved TN concentration of 3.0 mg∕L and TP concentration of 1.0 mg∕L. High-throughput sequencing was applied to analyze the microbial community structure in R2 and R3 in the early and matured stages. Proteobacteria and Bacteroidetes were found the main bacteria throughout the operation. Shannon-Wiener index increased both in R2 and R3 after the maturation of AGS, and the highest value in R2 was 5.4 indicating the best biodiversity and stability. In general, hydrolysis and acidification unit supplied key substrates fond for stable AGS granulation,which gave rise to good nitrogen and phosphorus removal and microbial diversity.%为研究水解酸化对AGS(好氧颗粒污泥)的形成及其脱氮除磷效果的影响,分别采用R1+R2两段式〔HUSB(升流式水解酸化池)-SBR〕和R3一段式(SBR)方式培养AGS,研究了不同基质下形成的AGS的脱氮除磷效果,并通过高通量测序对水解酸化污泥(R1)和R2、R3运行初期(12 d)与运行后期(97 d)的AGS微生物群落结构进行解析.结果表明,当进水基质为葡萄糖时, R1+R2两段式和R3一段式都能够成功地培养出颗粒致密、沉降性能好的AGS.接种活性污泥后的第13天R2反应器中形成粒径为>1.0~1.6 mm的颗粒污泥,而R3反应器仍以絮状污泥为主;颗粒污泥成熟后,R2中AGS的粒径增长至1.0~2.0 mm间,R3的粒径主要分布在>1.0~1.6 mm间.两种颗粒污泥对CODCr和NH3-N均有很好的去除效果,去除率均接近100%. R2对TN和TP的去除率分别为88.5%和72.8%,明显高于R3(67.2%和60.1%);R2出水ρ(TN)最低可达3 mg∕L,ρ(TP)可达1.1 mg∕L.高通量测序结果表明,Proteobacteria和Bacteroidetes门始终是主要菌种;随着好氧颗粒污泥的成熟,R2和R3的Shannon-Wiener多样性指数均显著增加;R2中成熟后AGS的Shannon-Wiener多样性指数最高(5.40),表现出良好的生物多样性和系统稳定性.研究表明,水解酸化为AGS的形成提供了关键基质,促进了好氧污泥颗粒化,培养出的AGS运行稳定,脱氮除磷效果好,微生物种群丰富.