硫自养反硝化强化垂直流人工湿地脱氮性能研究

Nitrogen Removal Performance of Vertical Flow Constructed Wetland Enhanced with Sulfur Autotrophic Denitrification

复合垂直流人工湿地在处理低碳氮比值污水时需外加有机碳源,增加了处理成本,且存在二次污染的可能。将单质硫与CaCO3以体积比为1∶1均匀混合后作为基质填充到复合垂直流人工湿地中以强化其脱氮效果,研究了HRT、NO-3-N浓度对系统脱氮效果的影响。结果表明,进水NO-3-N为3、10、15、20 mg/L,HRT=12 h时,系统对NO-3-N的去除速率分别为0.22、0.78、1.16、1.53 mg/(L·h),出水水质可达到我国地表水环境质量标准中的Ⅱ类标准。在HRT=12 h的条件下,分析了系统沿程氮形态的变化,探索了氮的去除途径。

The need to add organic carbon to the low C/N influent treated by vertical flow con- structed wetland leads to increased operation cost and secondary pollution. As substrate, S and CaCO3 with 1 ： 1 volumetric ratio were mixed evenly and dosed into the vertical flow constructed wetland to en- hance the nitrogen removal. The influences of HRT and NO3- - N on the denitrification were investigated. The results indicated that the removal rates of NO3- - N were 0.22 mg/（ L· h） , 0.78 mg/（ L· h） , 1.16 mg/（ L· h） and 1.53 mg/（ L ·h） for respective influent NO3- -N concentrations of 3 mg/L, 10 mg/L, 15 mg/L and 20 mg/L and HRT = 12 h. The effluent quality met the class II criteria specified in the Environmental Quality Standards for Su℃ace Water （ GB 3838 - 2002）. In addition, variation of the nitrogen form was analyzed at HRT = 12 h, and the removal pathway of nitrogen was researched.