填充率对悬挂链曝气式接触氧化工艺的影响研究

Effects of Packing Ratio on Performance of Contact Oxidation with Suspended-chain Aerators

采用悬挂链曝气式接触氧化工艺在不同的填料填充率时处理城市河道污水，应用磷脂法、TTC-脱氢酶活性法和MPN法研究了载体表面生物膜特性，考察了填充率对生物膜特性和水质净化效果的影响。结果表明：在20％-80％之间，填充率越大，缺氧区内单位体积填料上生物膜量越多，好氧区内单位体积填料上生物膜量越少和活性越低，水质净化效果越好；填充率由40％提高到60％后，缺氧区和好氧区内生物膜特性明显改变，系统对NH4^＋N和TN的去除率有很大提高，COD和TP的去除效果提高平缓；填充率为80％时，对COD、NH4^＋N、TN和TP的平均去除率最好，分别达到75．9％、78．42％、72．5％和51．7％。

This paper describes an experimental study intended to improve a process of contact oxidation by optimizing packing ratio of the biofilm carriers in treating sewage from the combined sewers. The study was carded out with a bench scale apparatus made of four compartments including anaerobic, anoxic and aerobic zones, as well as settlement zone, and into each of the compartment was fit biofilm carders and suspended-chain aerators. Besides, methods of phospholipid, dehydrogenase activity and MPN were used to probe into superficial biofilm characteristics. Findings of the study suggested that in the anoxic zone, the greater packing ratio （between 20% and 80%） was, the more biomass in the carder （per unit volume） would grow, whereas in the aerobic zone, the less biomass becamd, the lower the microbial activity of per unit volume would be. When increasing the packing ratio from 40% to 60%, the biofilm characteristics were obviously altered in the anoxic zone and aerobic zone, and the removal efficiencies of NH4^＋-N and TN were greatly improved, while the removal efficiencies of COD and TP were just evenly upgraded. Furthermore, when packing ratio was raised to 80%, the removal efficiencies on average in terms of COD, NH4^＋-N, TN and TP reached the highest as COD 75.9%, NH4^＋-N 78.42%, TN 72.5% and TP 51.7%, respectively.