应用生物强化技术处理高寒地区城市生活污水

Application of biological enhancement technology on treating urban domestic sewage in alpine regions

针对我国北方及西部高寒地区冬季气温低,活性污泥法处理污水效果不理想甚至无法运行的问题,通过筛选和驯化耐冷微生物菌群,培育出了适用于低温条件下高效处理生活污水的耐冷活性污泥,并在15、10和5℃条件下均取得了较好的污水处理效果。在低温(5℃)条件下的实验结果显示,人工摸拟生活污水的COD值(化学需氧量)最低可降到30 mg·L^(-1)以下,去除率在95%以上;氨氮值最低可降到2 mg·L^(-1)以下,去除率在86%以上。处理后的水质均在城镇污水处理厂污染物排放标准一级A标准以上,其污水处理效果远远高于同条件下非耐冷活性污泥。因此,利用该低温菌群强化高寒地区的城市污水处理,适用性很强,具有很高的应用价值。

Low winter temperatures in the alpine regions of western and northern China reduce the biological ac- tivity of activated sludge, which usually makes the urban domestic sewage treated by this hindered activated sludge unable to meet the Pollutant Discharge Standard of Municipal Wastewater Treatment Plants. In this study, screened cold-resistant microorganisms were domesticated, so they could purify low-temperature sewage efficient- ly. The results of this study demonstrated that the cold-resistant microorganisms obviously affected artificial sew- age treatment for the better at temperatures of 15 ℃ , 10 ℃ , and 5 ℃. When the temperature was 5 ℃ , the COD （chemical oxygen demand by the dichromate method） of the sewage decreased to 30 mg · L-1 or less, the re- moval efficiency of COD reached 95% or more, the NH4-N in the sewage dropped to 2 mg · L-1 or less, and the removal efficiency of NH4-N was more than 86%. The effluent quality after treatment with these cold-resistant mi- croorganisms met the Pollutant Discharge Standard of Municipal Wastewater Treatment Plants. The sewage treat- ment capacity of the cold-resistant microorganisms was much higher than it was for the non-cold-resistant activa- ted sludge, under low temperature conditions. Therefore, urban sewage treatment can be improved by using cold- resistant microorganisms in the alpine regions.