污水深度处理中稳定亚硝化单元工艺的试验研究

Experimental research on short-cut unit operation of stable nitrosification process in advanced treatment of municipal wastewater

常温下(17～24℃),以二级处理出水为原水,普通硝化污泥为种泥,通过控制曝气量创造较高的O2基质缺乏竞争梯度,成功启动短程硝化反应器,亚硝酸盐积累率高于90%。分别对0.03～0.60mg/L等9个DO水平下的氮素化合物转化规律及DO、pH和ORP等参数的变化规律进行了研究。结果表明,通过O2基质缺乏竞争途径实现污水深度处理中的稳定亚硝化单元工艺是可行的;DO曲线特征点是最理想的过程控制参数;DO为0.30mg/L是实现稳定亚硝化最理想浓度;DO、pH和ORP曲线特征点表征的是维持稳定亚硝化过程的转折点,而并非硝化终点。

Under normal temperature of 17~24 ℃, the experiment takes secondary wastewater as influent and conventional nitrifying sludge as inoculum to start up the short-cut nitrosification reactor, making use of the high selective grads of O2 substrate lack competition which is resulted from the different DO level, achieving a nitrite accumulation ratio over 90%, and the research into the variation rule of nitrogen compounds and operating variables of DO, pH and ORP in the nine DO level of 0. 03~0. 60 mg/L has been carried out. The result shows that the realization of the stable shortcut nitrosification unit process in advanced treatment of municipal wastewater via O2 substrate lack compe- tition is feasible. The characteristic point in the curve of DO is the perfect control parameter. The value of 0. 30 mg/L is the best concentration of DO that can keep the stable short-cut nitrosification. The characteristic points in the curve of DO, pH and ORP are symbols of the turning point of maintaining the stable short-cut nitrosification process, not of the nitrifying end-point.