输配水系统中硝化作用的影响因素研究

Factors Influencing Nitrification in Water Distribution System

在用氯胺消毒的管道模拟系统中研究了硝化作用下"三氮"(氨氮、亚硝酸盐氮、硝酸盐氮)及总氯的迁移转化规律,考察了水温、初始氯浓度、停留时间对硝化作用的影响。结果表明:水温、初始氯浓度对管道硝化作用的影响显著,水温越高则硝化现象越明显;提高初始投氯量,硝化作用会受到一定程度的抑制,但并不能从根本上避免硝化作用的发生;在5 d的停留时间里,管网水的亚硝酸盐氮和CODMn浓度均呈先增加后减小的趋势,溶解氧减少了72%,硝化作用明显。

The variations in ammonia nitrogen, nitrite nitrogen, nitrate nitrogen and total chlorine under nitrification in a simulated water distribution system were studied. The effects of water temperature, initial chlorine concentration and hydraulic retention time （HRT） on the nitrification were investigated. The results indicate that water temperature and initial chlorine concentration have a significant impact on the nitrification. Raising the temperature can increase occurrence of nitrification, while raising the initial chlorine dosage can prevent the nitrification to some degree, and the nitrification cannot be completely avoided. When HRT is 5 d, nitrite nitrogen and CODMn first increase and then subsequently decrease, DO decreases by 72% , and the nitrification is evident.