正反粒径混合级配钢渣灰岩人工湿地处理生活污水的试验研究

Construction of steel slag-limestone wetland with mixed progressively-sized and anti-sized bed for living sewage treatment

构建小试试验研究了正反粒径混合级配填铺与正粒径级配填铺（组合填料为钢渣与灰岩）的垂直潜流人工湿地单元对生活污水中各主要指标的降解效果,同时比较分析了填料填铺方式对缓解人工湿地堵塞问题的影响。结果表明,当原水COD在134.72-653.33 mg/L、NH3-N在42.72-272.60 mg/L,TN在107.40-689.35 mg/L、PO34--P在1.29-8.36 mg/L时,正反粒径混合级配填铺的人工湿地对COD、NH3-N、TN的去除效果略好于正粒径级配填铺的人工湿地。钢渣与灰岩的组合填料适于生活污水的处理,尤其利于氮、磷的去除。在运行末期,正反粒径混合级配填铺人工湿地单元出流体积大于正粒径级配填铺人工湿地单元,而前者出流时间短于后者。因此,正反粒径混合级配填铺可在一定程度上缓解人工湿地的堵塞状况。

Two parallel lab-scale steel slag-limestone construct wetlands were established for treatment of living sewage.The two wetlands had same configuration but different arrangement of bed media,namely progressively-sized bed and mixed progressively-sized/anti-sized bed.The performance of two wetlands were studied and compared,the clogging problems caused by different bed structure were analyzed.Experimental results indicated that the mixed bed systems had considerable capacity for the removal of organic matter and inorganic nutrients,when the concentration range of COD,NH3-N,TN and PO3-4-P was 134.72-653.33,42.72-272.60,107.40-689.35 and 1.29-8.36 mg/L,the removal rate of COD,NH3-N and TN by mixed bed system was little higher than that of progressively-sized system.The steel slag and limestone mixed filling was benefit for dealing living sewage,especially for removing nitrogen and phosphorus.At then end of operating period,the effluent volume of mixed bed systems was larger than that of progressively-sized bed system,while the effluent time of the former was shorted,which demonstrated a clear advantage of mixed bed system in slow down the clogging of bed media.