SBR法处理豆制品废水过程中ORP与COD的相关性

Correlation of ORP and COD in SBR Process Treating Soybean Processing Wastewater

采用SBR法处理豆制品废水时 ,为获得准确反映有机物降解情况的控制参数 ,进行了反应过程中ORP变化与COD降解程度的相关性试验研究。结果表明 ,无论改变曝气量还是初始MLSS浓度 ,以及增加或减少进水COD浓度 ,反应过程中ORP的变化与COD的降解程度均具有很好的相关性。在降解COD过程中 ,ORP变化曲线出现两个特征点 ,一个特征点为ORP凹点 (最小值 ) ,它表示反应器中大部分COD已被降解 ;另一个特征点为ORP平台 ,表示COD达到难降解程度。此外 ,不同进水COD浓度使得ORP曲线凹点出现的时间不同 ,以此可以预测进水COD浓度 ,为实现曝气量和曝气时间的在线模糊控制奠定理论基础。

A Sequencing Batch Reactor (SBR) was operated to treat soybean wastewater. In this process, in order to achieve reliable exact control parameter of COD removal, the relationship between the COD removal and ORP value in the reactor was examined. As a result, unexceptionable correlation between the diversification of ORP and the COD degradation has been observed at any condition of different inflow organic loadings, aeration intensity and MLSS concentration. Two distinct inflection points were observed throughout SBR processing cycle. The first inflection point was observed as the ORP concave value, and it expresses that a majority of COD has been removed. The second inflection point was observed as flat roof, and it showed that COD was not removed. In addition, inflow COD concentration and the time that ORP concave value appeared was connected, and the speed that ORP in curve ascended related with the COD concentration during the degradation. Hence, it can be used for predicting the concentration of inflow COD by using ORP, and make on line fuzzy control of aeration intensity and aeration time.