Orbal氧化沟生物脱氮的中试研究

采用有效容积为330L的中试Orbal氧化沟模型处理城市污水,研究了Orbal氧化沟的同时硝化反硝化生物脱氮现象。结果表明,Orbal氧化沟具有良好的降解有机物和硝化性能;在不投加外碳源和不设硝化液内回流的条件下,通过控制DO浓度分布,可以实现氧化沟内的同时硝化反硝化,对总氮去除率平均为61%,出水总氮平均为14mg/L。经分析认为,DO浓度分布是氧化沟内同时硝化反硝化的决定因素,进水中的COD/TN是影响总氮去除率的重要因素;通过控制外沟低DO运行,可以稳定实现Orbal氧化沟的低能耗高效脱氮;多沟道串联的反应器布置方式有效防止了低DO运行带来的亚硝酸盐积累和污泥膨胀的发生。

Pilot Study on Orbal Oxidation Ditch for Biological Nitrogen Removal

A pilot-scale Orbal oxidation ditch with effective volume of 330 L was used for the municipal wastewater treatment, and the phenomenon of simultaneous nitrification and denitrification (SND) was investigated. The result shows that the Orbal oxidation ditch has good performance in organic degradation and nitrification. By means of controlling the dissolved oxygen (DO) concentration, SND can be achieved without any inner recycle and external carbon added, the removal rate of total nitrogen (TN) is averaged at 61% with effluent TN of 14 mg/L in average. It is believed that DO concentration is the decisive factor of SND occurring in Orbal system, and the influent COD/TN is the key factor affecting TN removal rate. By controlling DO at low level in the outer channel, highly efficient nitrogen removal can be achieved steadily with low energy consumption. The reactor with serial arrangement of multi-channel can effectively prevent the nitrite accumulation and sludge bulking incurred by low DO.