溶解氧对分段进水生物脱氮工艺的影响

 采用分段进水生物脱氮工艺处理生活污水.设置0.9,0.6,0.4,0.3m³/h4组曝气量,相应的好氧区溶解氧(DO)浓度约为2.8,1.7,0.8,0.5mg/L左右.结果表明,在好氧区DO为0.5mg/L左右的低氧条件下,通过对系统进行适当的控制,可以取得较好的硝化效果,氨氮去除率可达98%以上.同时,由于低曝气量下混合液从好氧区到缺氧区携带的DO量减少,并且在好氧区发生了同步硝化反硝化作用,使得TN去除效果明显优于高曝气量的情况.另外,由于工艺结构的特点,分段进水生物脱氮系统可长期在低氧条件下运行,且污泥沉降性能良好.

The effect of dissolved oxygen on the lab-scale step-feed biological nitrogen removal process

The effect of dissolved oxygen (DO) on the lab-scale step-feed biological nitrogen removal process treating domestic wastewater was investigated. Different DO concentration in aerobic tank 2.8, 1.7, 0.8, 0.5mg/L was obtained by controlling the aeration rates, which was 0.9, 0.6, 0.4, 0.3m3/h, respectively. Better nitrification efficiency could be obtained with appropriate control under lower DO concentration of 0.5mg/L in the aerobic tank, the ammonia removal efficiency was more than 98%. Simultaneously, due to the decreased DO circulated from the aerobic tank to the anoxic tank and the simultaneous nitrification and denitrification (SND) that occurred in the aerobic tank under lower DO concentration, the total nitrogen removal efficiency under lower DO concentration was far better than under higher DO concentration. In addition, the long-time stable operation of the step-feed biological nitrogen removal process with better sludge settling performance under lower DO concentration was attributed to the special process configuration.