自养脱氮滤池在工业园区污水处理厂的工程应用

Application of autotrophic denitrification filter in one industrial park’s wastewater treatment plant

自养脱氮滤池作为污水处理厂二级生化后的深度脱氮技术,选用2~3mm粒径的自养活性滤料,稳定实现出水TN≤10mg/L,且零(或低)碳源添加,助力降碳排量。下向流的自养脱氮滤池,HRT约20min,进水DO高于4mg/L时,平均脱氮浓度仍达8.50mg/L,脱氮率67%,脱氮负荷0.64kg/(m^(3)·d),其药耗较异养脱氮时可降耗30%~50%,宜控制脱氮滤池的进水DO≤2mg/L。自养脱氮滤池需长期关注NO2-N、S^(2-)、SO4^(2-)等副产物累积的不利影响。

Autotrophic denitrification filter would be a deep-enhanced denitrification technology joined after the secondary biochemical treatment unit,in which filter-media was used with two to three particle size,as well as special autotrophic slowly-released&active characteristics,effluent total nitrogen index could be stably below 10 mg/L,as well as reduction of carbon emission with zero(or low)carbon source.As for the autotrophic denitrification filter of down-flow,In condition of HRT is about 20 min,influent DO level of no less than 4 mg/L,average nitrate nitrogen removal concentration could still be 8.50 mg/L,nitrate nitrogen removing efficiency of 67%,nitrate nitrogen volumetric loading of 0.64 kg/(m^(3)·d),and 30%to 50%ratio saving compared with what in the heterotrophic denitrification filter.Influent DO level of denitrification filter should be less than 2 mg/L.Long term attention should be paid to the accumulation and side effects of nitrite nitrogen,sulfide or sulfate.