碳源对榨菜废水与城镇污水协同处理效果的影响

Effects of Different Carbon Sources on Co-treatment of Pickle Wastewater and Municipal Sewage

针对CASS工艺协同处理高盐、高氮磷榨菜废水和城镇污水过程中碳源不足的问题,分析了CASS工艺在运行周期为8 h、排水比为30%、回流比为100%、经预处理的榨菜废水掺入比为20%的条件下,分别投加污泥消化液、榨菜废水和甲醇三种碳源对协同处理效果的影响。当污泥消化液、榨菜废水和甲醇的投加量分别为15%、3%和0.015%时,出水COD、氨氮和总氮浓度均满足GB 18918—2002的一级B排放标准;以聚合硅酸铁为除磷剂,当进水TP约为8.5 mg/L、除磷剂投量为18 mg/L时,对TP的去除率达90%以上,且出水浓度小于1.0 mg/L;硝化菌和反硝化菌对盐度变化的适应周期不同,当系统盐度为(0.5±0.03)%、等幅度升高和降低(0.1±0.02)%时,硝化菌的适应周期分别为7 d和10 d,而反硝化菌的适应周期分别为10 d和15 d。

To address the deficiency of carbon source during co-treatment of pickle wastewater with high salinity and nitrogen content and municipal sewage by the CASS process, the effects of co-treatment were analyzed by dosing three kinds of carbon sources, including sludge digestion liquid, pickle wastewater before treatment and methanol. For CASS operation, the operation time was 8 h, the drainage ratio was 30% , the recycle ratio was 100% , and the ratio of adding pretreated pickle wastewater was 20%. When the dosages of sludge digestion liquid, pickle wastewater before treatment and methanol were 15% , 3% and 0.015% , respectively, the effluent concentrations of COD, NH4＋ -N and TN could meet the first level B criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treat- ment Plant （GB 18918 -2002）. Using polymeric ferric silicate as phosphorus removal agent, the remov- al rate of TP was above 90% and the effluent concentration was less than 1.0 mg/L when the influent concentration of TP was about 8.5 mg/L, and the dosage of phosphorus removal agent was 18 mg/L. The times to adapt to variations of salinity were different for nitrifying bacteria and denitrifying bacteria. When the system salinity deviated from the initial （0.5 ±0. 03 ） % by （0.1±0. 02） % up and down, the adaptation periods for nitrifying bacteria were 7 d and 10 d, while for denitrifying bacteria were 10 d and 15 d, respeetively.