应用实时控制实现和稳定短程硝化反硝化

Application of Real Time Control for Achieving and Stabilizing Short-cut Nitrification and Denitrification

以实际豆制品生产废水为处理对象,采用SBR反应器研究了过度曝气(曝气时间过长)对短程硝化的影响,在此基础上提出了应用实时控制技术在常温、正常溶解氧和中性pH值时实现和稳定短程硝化的新方法。试验结果表明,在反应器温度为(28±0.5)℃、过度曝气12周期后,硝化类型就由亚硝酸盐积累率为96%的短程硝化转变为亚硝酸盐积累率为39%的全程硝化;而应用实时控制策略在反应器温度为(27±0.5)℃和(25±0.5)℃时可较好地维持短程硝化反硝化,且经过两个月的运行硝化类型也没有改变,亚硝酸盐积累率仍然保持在96%以上。因此可以得出,好氧反应时间的控制在亚硝化阶段基本结束时是维持并稳定短程硝化的关键。实际上,即使在能充分实现短程硝化的条件下,过度曝气也能使短程硝化向全程硝化转化。

With regard to the treatment of soybean wastewater, study was made on the effect of overaeration (too long period for aeration) on short-cut nitrification and denitrification by using SBR. On this basis, a new method was proposed, in which the real time control technology was applied for achieving and stabilizing short-cut nitrification and denitrification under the conditions of ambient temperature, normal )DO) and neutral pH. The test result showed that at the reactor temperature of (28±0.5)℃ and after overaeration for 12 cycles, short-cut nitrification with nitrite accumulation rate of 96% is changed into whole-run nitrification with nitrite accumulation rate of 39%; while the real time control strategy is used, short-cut nitrification and denitrification can be kept in good state under the reactor temperature of (27±0.5)℃ and (25±0.5)℃, without any change in nitrification mode after operation of two months. Therefore, it may be concluded that control of aerobic reaction ending at nitrosation stage is the key to the maintenance and stabilization of short-cut nitrification. In fact, even though short-cut nitrification is fully achieved, overaeration can have the short-cut nitrification change to whole-run nitrification.)