OGO工艺处理城市污水的脱氮除磷效能与水力特性的试验研究

Experimental study on nitrogen and phosphorus removal of municipal wastewater and hydraulic characteristics in OGO

在OCO反应器的基础上改进得到了OGO反应器.在反应器改进前后脱氮除磷效能对比试验的基础上,进行了反应器水力特性的试验研究.城市污水对比试验研究结果表明,OGO工艺较改进前具有更为稳定、良好的生物同时脱氮除磷效果,工艺出水的平均值COD为22mg·L-1、NH4+-N为4.8mg·L-1、TN为11.2mg·L-1、TP为0.80mg·L-1.反应器流态特征的试验结果表明,改进后形成的OGO反应器内,缺氧环区形成了良好的DO浓度梯度分布,且OGO反应器内推流流态所占比例从改进前的5.9%提高到改进后的12.9%,有效提高了反应器内推流流态的容积利用率和反应器效率.同时,反应器改进后能明显改善混合区水力条件,并有效避免了混合区内侧液流涡旋停滞造成的污泥沉积问题.

There was a close relationship between bio-chemical process characteristics, removal efficiency of pollutants and hydraulic characteristics of mixing liquid for a biological reactor. OGO process was a renovation reactor which developed from OCO. Based on the comparative tests of nitrogen and phosphorus removal in OCO and OGO, experiments of hydraulic characteristics were carried on. Results of comparison experiments for municipal wastewater showed that the simultaneous removal efficiency of nitrogen and phosphorus and stability in OGO were better than in OCO under the same operation conditions. The average effluent concentration of COD, NH4^＋ -N, TN and TP were 22 mg·L^-1, 4.8 mg·L^-1, 11.2 mg·L^-1, 0.80 mg·L^-1 respectively. Study results of flow pattern characteristics showed that DO concentration gradient in inner-loop anoxic zero of OGO was better compared with OCO. And proportion of plug-flow was increased from 5.9% to 12.9% after renovation, which leading to higher utilization rate of plug-flow pattern and reaction efficiency in OGO. Meanwhile OGO could improve the hydraulic behavior of mixing zone remarkably, and avoid the problem of sludge-settlement in mixing zero effectively.