一体化OCO工艺脱氮除磷效果优化的ORP调控策略

ORP Strategies for Optimizing Removals of Nitrogen and Phosphorus in Integral OCO Process

该文研究了不同HRT、DO、pH、MLSS条件下双侧沟式一体化OCO工艺中ORP的变化规律,以及工艺在不同工况下脱氮除磷的效果。通过分析ORP与工艺条件之间的相互关系,结果表明在污水处理中ORP可以作为此工艺脱氮除磷的控制参数:ORP与HRT、DO、pH、MLSS的关系可以描述如下:ORP=498.5+245.7×ln DO-358.5×lnpH+12.1×HRT+45.3×cos(0.9×MLSS+166.7),相关系数R^2=0.921。ORP与各物料做相关性分析显示,ORP与COD去除量显著相关(p≤0.05),与COD去除率、TP去除量、TP去除率、NH_4^+-N去除量、NH_4^+-N去除率、出水NO_3^--N、出水NO_2^--N、TN出水、TN去除量、TN去除率呈极显著相关(p≤0.01)。一体化OCO工艺脱氮除磷的效果与ORP显著相关,且调控ORP实现了一体化OCO工艺脱氮除磷效果的优化及工艺的稳定高效运行。

Bench-scaled experiments were conducted with a laboratory installation which simulating the integrated OCO reactor with two side-ditch separator operating in A2/O （anaerobic/anoxic/oxic） process for treatment of municipal wastewater. This paper focused on the regularity of variation and removals of nitrogen （N） and phosphorus （P） under different conditions in regards to operating parameters including HRT, DO, pH and MLSS. The experimental study suggested that ORP acted as the controlling parameter of N and P removals, and the relationship between ORP and HRT, DO, pH and MLSS was described as ORP=498.5＋245.7xlnDO-358.SxlnpH＋12.1xHRT＋45.3xcos（0.9xMLSS＋166.7）, and R^2=0.921. Besides, analysis on the correlation between ORP and each parameter indicated that ORP significantly correlated with the pollutants in wastewater, i.e. ACOD （p≤0.05）,followed by the removal rates of COD, TP, NH4＋- -N, TN, ATP and ANI-L＋- -N, as well as with the parameters in effluent i.e.NO3- -N, NO2- -N and TN （p≤0.01）. Summarily, ORP could be served as an effective indicator of the nitrogen and phosphorus removal for operating the integral OCO process; in addition, it was possible to realize optimizing and stable running of nutrients removal in the integral OCO process by the way of controlling the ORP variation.