焦化废水厌氧氨氧化的抑制特征与调控策略研究

Coking wastewater contains organic contaminants which are refractory, toxic, mutative, and carcinogenic and high ammonia concentration. Anaerobic-anoxic-oxic (A2O) is the conventional biological nitrogen removal process of coking wastewater. However, the operation exist disadvantages, such as that the oxygen demand is high, it need extra carbon source, the operation cost is high and it is not efficient enough to meet the strict requirements of the National Discharge Standard of China. Laboratory scale Sharon/Anammox nitrogen removal process is established to treat manmade coking wastewater containing nitrogen heterocyclic Compounds, SCN- and CN-. The variation of microbial community structure is analyzed by PCR, DGGE and quantitative PCR. The Anammox activity inhibition mechanism is clarified based on the analysis of bacterial composition, HAO enzymatic activity, biological chemical metrology and Anammox metabolism process. BP neural networks model is constructed to predict the effluent quality. Based on inhibition mechanism, influent quality, predicted effluent quality and the characters of different activity recovery means, the control strategy of stable operation of Anammox nitrogen process is proposed. The research will enrich coking wastewater biological treatment theory and lay the foundation for the wastewater treatment process rationalization, scientific design and operation.

焦化废水含有多种难降解有机物和高浓度氨氮。目前多采用A2O工艺进行处理，但A2O工艺耗氧量大、需外加碳源、运行费用高却难以达到排放标准。本研究采用Sharon/Anammox工艺处理焦化废水，主要考察含氮杂环化合物、SCN-和CN-对工艺脱氮效能的影响规律。采用PCR、DGGE和实时定量PCR等分子生物学技术，考察脱氮系统内菌群结构变化；结合菌群结构变化、生物化学计量学分析、HAO酶活性分析及Anammox菌代谢过程，明晰Anammox菌活性抑制机理。建立BP神经网络模型预测工艺出水水质；结合抑制机理、进水水质、出水预测水质及不同活性恢复手段的特性，提出防治Anammox菌活性抑制、维持工艺高效稳定运行的调控策略。该研究成果将为传统A2O工艺改造成高效节能的Sharon/Anammox工艺提供理论基础，为焦化废水处理工艺合理化、科学化设计与运行奠定基础。

焦化废水含有多种难降解有机物和高浓度氨氮。目前多采用A2O工艺进行处理，但A2O工艺耗氧量大、需外加碳源、运行费用高却难以达到排放标准。本研究采用Sharon/Anammox工艺处理焦化废水，主要考察含氮杂环化合物喹啉对工艺脱氮效能的影响规律。研究表明，50-150 mg/L喹啉添加促使自养短程硝化污泥氨氧化菌活性增加，氨氮的转化速率提高100-200%，喹啉消耗率低于66.6%；但是，对于喹啉降解-短程硝化系统，氨氮全部转化为亚硝酸盐氮，喹啉基本完全降解，氨氧化菌活性未显著增加；DGGE代表性条带测序结果表明，二者系统功能菌种显著不同，自养短程硝化系统中Acidovorax sp. JS42和Acidovorax ebreus TPSY参与氨转化过程，喹啉降解-短程硝化系统中的功能菌为N. europaea和Nitrosomonas eutropha。在稳定运行的Anammox系统内，添加20mg/L的喹啉，导致系统氮脱除率显著降低；高通量测序分析结果表明，喹啉抑制期间，厌氧氨氧化菌（Ca. Brodica 、Ca. Jettenia 及Ca. Kuenenia Scalindua）百分含量显著下降，异养菌Acinetobacter和Sphingobium丰富度升高；停止喹啉添加以及降低流量，60天后系统恢复氨氮和亚硝态氮处理效能，氮是硝化过程对氨氮和亚硝态氮的去处贡献率显著上升达到18.6%；Ca. Jettenia成为主要功能菌。SCN-和CN-对Anammox工艺脱氮效能的影响规律正在开展研究。