厌氧环境对UNITANK工艺性能的影响

Effect of Anaerobic Environment on Performance of UNITANK Process

以赣南地区低碳源实际城市污水为研究对象,分析了UNITANK工艺中边池厌氧时间对系统脱氮除磷性能的影响。结果表明,当内回流比为100%时,随着边池厌氧时间的增加,TN去除率呈现先增加后减小的趋势,而TP去除率则逐渐增大;边池厌氧时间对COD、NH_3-N的去除效果影响较小。当厌氧时间为60 min时,出水COD、NH_3-N、TN、TP的平均浓度分别为11. 07、0. 93、11. 78、0. 85 mg/L,除TP外其他3项指标均优于《城镇污水处理厂污染物排放标准》(GB18918—2002)的一级A标准要求;通过考察试验装置边池半周期内各组分浓度的动态变化,在边池厌氧时间为100 min的条件下,厌氧释磷现象最为明显,边池NO_2^--N积累浓度最高,边池存在反硝化过程和释磷过程对碳源的竞争问题。

The effect of the anaerobic time in the side tank on the efficiency of nitrogen and phosphorus removal of the UNITANK process was investigated based on the actual municipal sewage from the south Jiangxi area. The results showed that when the internal reflux ratio was 100%, with the increase of the anaerobic time in the side tank, the removal rate of TN was firstly increased and then decreased, while the removal rate of TP increased gradually. The anaerobic time in the side tank had negligible effect on the removal efficiency of COD and NH3 - N. When the anaerobic time was 60 min, the average concentrations of effluent COD, NH3 - N, TN and TP were 11. 07 mg/L, 0.93 mg/L, 11.78 mg/L and 0.85 rag/L, respectively. All indicators except TP had satisfied the first level A standard in the Discharge Standards of Pollutants for Municipal Wastewater Treatment Plant （ GB 18918 - 2002 ）. The dynamic changes of the the anaerobic time in concentration of NO2- phosphorus release in component concentrations in the half cycle of the side tank were investigated. When the side tank was 100 min, the anaerobic phosphorus release was obvious, and the - N in the side tank was at the highest level. The processes of denitrification and the side tank competed for the carbon source.