UniTank工艺流程溶解氧浓度动态分析

利用活性污泥数学模型ASM2D建立了上海石洞口污水处理厂UniTank工艺流程的仿真模型,根据该仿真模型,分析了曝气强度和排泥速率对溶解氧浓度的影响.研究结果表明,该流程各反应器内溶解氧浓度具有非稳态特征,溶解氧浓度与曝气强度及排泥速率有关.曝气强度越大,反应器内溶解氧浓度越高;中池曝气强度的变化,会在一定范围内影响边池的溶解氧浓度.增加排泥速率,会降低反应器内混合液挥发性悬浮固体的浓度,并增大边池的溶解氧浓度.本研究结果对UniTank工艺溶解氧浓度的合理调控提供了理论依据.

Non-steady state dissolved oxygen concentration in UniTank processing

The article is aimed at presenting the authors' environmental engineering UniTank processing simulation model, which is built up based on an activated sludge model known as ASM2D. The mathematical model of the UniTank process has been set up in the Shanghai Shidongkou Urban Sewage-treating Plant for analyzing the dynamic behavior of the dissolved oxygen concentration of the vessels in the UniTank processing. For this purpose, we have investigated and analyzed the dynamic behavior of dissolved oxygen concentration in the plant by changing the aeration intensity and the rate of sludge discharge. The results show that the dissolved oxygen in the UniTank process is on a non-steady state. The change of dissolved oxygen concentration is in fact affected greatly by aeration intensity and the rate of sludge discharge. It proves that the larger the aeration strength, the higher the dissolved oxygen concentration of the vessel. Changing the aeration strength in a certain range in the central part of the vessel may have effect on the concentration of the dissolved oxygen in the side of the vessel. Increasing the rate of sludge discharge may also lead to the decrease of the concentration of mixed liquid volatile suspended solids, correspondingly reducing the oxygen consumption by the biomass and increasing the dissolved concentration in the vessels. Moreover, the variation of the concentration of the species can also be influenced by the aeration strength and the rate of the sludge discharge. Thus the results can be made to serve as a theoretical foundation for rational control of the dissolved oxygen concentration of the vessels in the UniTank process.