脉冲水解酸化-A/O生物反应器处理石化废水的中试研究及微生物群落结构解析

 采用自行设计的脉冲布水器，建造脉冲水解酸化-A/O（厌氧好氧工艺法）中试装置处理实际石化废水。水解酸化池和A/O的容积分别2.6 m³和3.9 m³；脉冲布水器的频次为10次/h；A/O池污泥龄25 d，污泥回流比100%，温度15~32℃。反应器稳定运行近7个月的结果表明：尽管进水化学需氧量（COD）和氨氮波动较大，但出水COD和氨氮的去除率保持稳定。在进水COD质量浓度为（458±107）mg·L^-1，系统COD去除率为80%，其中脉冲水解酸化池（PHA）的COD去除率为29%。进水氨氮质量浓度为（35.9±11.3）mg·L^-1，系统氨氮的去除率为86%。UV₂₅₄和TN的平均去除率约为58%，TP去除率可达86%。PHA泥水混合良好，出水挥发性脂肪酸（VFA）浓度比进水提高近1倍，BOD₅（5天生化需氧量）/COD值比进水提高35%，显示其良好的水解酸化效果，并可提高进水的可生化性。Ilumina Miseq测序结果表明：变形菌门（Proteobacteria）和拟杆菌门（Bacteroidetes）是主要的优势菌群，所占的比例在50%以上。在属的水平上，Anaerolineaceae和Clostridiales在水解酸化池中丰度较高；A/O池中丰度较高的菌属为Flexibacter，Thiobacillu，Nitrosomonadaceae和Nitrospira。通过反应器各段不同微生物种群的共同作用，石化废水中复杂的有机污染物得以有效降解。结果表明，脉冲布水水解酸化-A/O工艺是一种很有前途的石化废水处理技术，并可应用于其他工业废水的处理。

Pilot-scale study on treatment of petrochemical wastewater by hydrolysis-acidification with pulse water allocation and anoxic/oxic processes and analysis of microbial community

In the present study, a pilot-scale process of anaerobic hydrolysis-acidification with pulse water allocation (PHA) and anoxic/oxic (A/O) reactors was developed to treat actual petrochemical wastewater. The effective volume of PHA and A/O reactor was 2.6 m³ and 3.9 m3, respectively. The impulse frequency of the pulse tank was 10 times per hour. The sludge retention time of A/O reactor maintained at 25 d. The sludge from the settling tank was recycled into the anoxic tank with a recirculation ratio of 100%. The temperatures of the system ranged 15~32℃. The results during nearly 7-months operation showed that the removal efficiency of COD and ammonium remained stable although the influent COD and ammonium fluctuated. At the influent COD concentration of (458 ±107) mg·L^-1, the COD removal efficiency reached 80% on average, in which the PHA reactor contributed around 29% COD removal. The average ammonium removal was 86% at the influent ammonium concentration of (35.9 ±11.3) mg·L^-1. The removal efficiency of UV₂₅₄ and TN was around 58%. The TP removal could reach 86%. The PHA reactor exhibited good mixing of wastewater and sludge and a higher efficiency of acidogenic fermentation. The VFA levels in the PHA effluent were higher nearly twice than that in the influent. The ratio of BOD₅/COD of PHA effluent increased by 35% compared to that in influent, indicating that the biodegradability of the petrochemical wastewater was improved by PHA treatment. Results of Ilumina Miseq pyrosequencing demonstrated that Proteobacteria and Bacteroidetes were highly enriched in the system with abundance of more than 50% at the phylum levels. The predominant genera in PHA and A/O tanks were Anaerolineaceae and Clostridiales, Flexibacter, Thiobacillus, Nitrosomonadaceae and Nitrospira, respectively. The complex petrochemical wastewater was degraded efficiently owing to combined contribution of different bacteria in each tank. The above results demonstrate that the PHA-A/O process is a promising technique to treat petrochemical wastewater and could be applied in the treatment of other industrial wastewater.