污水的光化学灭菌处理研究

Photochemical Disinfection of Wastewater.

以日光和中压汞灯为光源，以亚甲基兰（下简称ＭＢ）为光敏剂，研究了南京市某污水样的灭菌处理和从灭菌水样中除去ＭＢ的方法．结果表明：光源、光强、光照时间、ＭＢ用量和溶解氧等因素对灭菌有显著影响；不加ＭＢ的水样经紫外光（下简称ＵＶ）灭菌后，在日光下细菌呈现复活（下简称光复活）；当１Ｌ细菌总数为３．１×１０６个／ｍｌ的污水加入２ｍｇＭＢ，并在充气状态下以３００Ｗ中压汞灯光照４ｍｉｎ，其灭菌率达１００％，且无光复活；同样条件下日光的灭菌率则低很多；水样中残余的ＭＢ用膨润土可有效除去．

A new method of photochemical disinfection for wastewater from Nanjng city was investigated. By ae rating and using methylene blue(MB) as photosinsitizer,the wastewater samples were disinfected under sunlight and a medium pressure mercury lamp separately. The results were as follows: (1) The disinfection of wastewater were remarkably affected by the light sources,light intensity,irradiaded time,MB concentration and dissolved oxygen; (2) The bacteria which were disinfected by UV could be partially photoreactivated under sunlight; (3) The disinfection rate could reach 100% and the bacteria photoreactivation were not appeared when l liter of the sample containing 3.1×10 6 bacteria and 2 mg MB were irradiaded by a 300W medium pressure mercury lamp for 4 min;(4) The residual MB in the samples could be removed by bentonite clay. The disinfection mechanisms of UV and photosensitization,the bacteria photoreactivetion and the effects for affecting disinfection were discussed.