梯度增加NH_(4)^(+)-N负荷低温启动改良A/A/O工艺研究

Study on Improving A/A/O Process by Gradient Increasing Ammonia Nitrogen Load and Starting at Low Temperature

在低温下通过梯度增加进水NH_(4)^(+)-N浓度的方法启动改良A/A/O耦合流离生化工艺,其中将启动阶段分为四个工况,每个工况NH_(4)^(+)-N浓度梯度递增约5 mg/L。反应器在温度(15±1)℃条件下,控制HRT为12 h,污泥回流比为100%,硝化液回流比为200%,填料填充率为30%的条件下经过43天启动成功。启动期间出水稳定,COD低于50 mg/L,NH_(4)^(+)-N保持在1.5 mg/L以下,TP保持在0.5 mg/L以下,TN保持在15 mg/L以下。启动后,系统的生物量得到了稳定增长,存在大量杆菌与球菌,且系统的好氧隔室内发生了同步硝化反硝化反应。梯度增加进水NH_(4)^(+)-N浓度时系统微生物适应良好,可快速恢复活性进行大量繁殖,能有效提高污染物去除效率,有利于改良A/A/O耦合流离生化工艺的启动。

At low temperature,the improved A/A/O coupled flow separation biochemical process was started by gradient increasing the influent NH_(4)^(+)-N concentration.The start-up stage was divided into four working conditions,and the NH_(4)^(+)-N concentration gradient of each working condition was increased by about 5 mg/L.The temperature of the reactor was(15±1)Under the conditions of HRT of 12 h,sludge reflux ratio of 100%,nitrification liquid reflux ratio of 200%and filler filling rate of 30%,the start-up was successful after 43 days.During the start-up period,the effluent was stable,COD was less than 50 mg/L,NH_(4)^(+)-N was less than 1.5 mg/L TP was less than 0.5 mg/L,TN was less than 15 mg/L.After the start-up,the biomass of the system increased steadily,and the simultaneous nitrification and denitrification occurred in the aerobic compartment of the system.When the influent NH_(4)^(+)-N concentration is increased gradiently,the system microorganism adapts well,can quickly recover its activity and propagate in large numbers,can effectively improve the pollutant removal efficiency,and is conducive to the start-up of the improved A/A/O coupled flow separation biochemical process.