异养硝化-好氧反硝化为焦化废水处理革新提供了新思路.从某焦化废水处理厂活性污泥中分离获得一株高效的异养硝化-好氧反硝化菌株HNAD4,经16S rRNA鉴定为Pseudomonas sp..分析了菌株HNAD4的硝化、反硝化以及同步硝化反硝化(SND)性能,研究了菌株对实际焦化废水的处理能力.结果表明,当菌株以柠檬酸钠为碳源、C/N为15、温度为35℃、pH为7.0时,硝化性能最优;以NO3--N和NO2--N为混合氮源时,两种氮源可同步去除,但反硝化优先利用NO3--N;以NH4+-N、NO3--N和NO2--N为混合氮源时,SND过程中利用氮源的优先顺序依次为NH4+-N、NO3--N和NO2--N;当处理实际焦化废水时,与对照组相比,投加菌株的实验组可使A/O1/O2工艺中O1池的NH4+-N去除率提高46.45％、TN去除率提高33.14％.
喹啉、吡啶等含氮杂环化合物是焦化废水中主要的难降解有机物.以喹啉、吡啶作为目标污染物,研究了筛选出的高效降解菌红球菌(Rhodococcus sp.)KDPy1对焦化废水A/O2生物处理工艺的强化作用.结果表明,与对照组相比,红球菌的添加使O1池的COD、喹啉、吡啶去除率分别增加了11.4％、17.3％、14.0％.经生物强化后,系统内微生物群落多样性增加,且有机污染物降解菌如Stenotrophomonas和Ochrobactrum等更具优势,证实了红球菌(Rhodococcus sp.)KDPy1在焦化废水处理中的巨大应用前景.
Coking wastewater is a typical refractory industrial wastewater with high organic load.The increasingly stringent effluent discharge standards have posed great challenges to traditional coking wastewater treatment processes.Coking wastewater treatment system is typically a combination of pretreatment, biological treatment and advanced treatment.Therein, biological treatment, as the main body and the key segment of the whole system, has the advantages of low cost and no secondary pollution, and plays an important role in the removal of refractory organic matter.However, the biological processes are generally confronted with the problems of low efficiency and unstable operation due to the extremely low biodegradability and large fluctuation of coking wastewater quality.In view of these problems, this paper mainly reviews the analysis techniques of coking wastewater quality as well as various pretreatment, biological treatment and advanced treatment technologies.In particular, the microbial consortium structure and function of degrading-bacteria of pollutant in the bio-treatment section are summarized.The various emerging water treatment technologies are prospected.All these results provide a theoretical basis for the optimization of coking wastewater treatment technology and development of the new technology in the future.
