Research And Utilization Of Activated Sludeg Models Based On ASM2

Design and selection of Activated sludge technology always are conducted based on experience in China. There is a very wide range of some key parameters in"sludge age"method which is often used in design, which leads to waste of expense of capital construction and operation. And technology selection usually is conducted according to subjective judgment and experience of designers, in fact, it is not really useful. Moreover, the properties of wastewater are very different in different countries, obviously this method based on experience lacks of scientific evidence. With the standard of discharging waste water becomes stricter, the method based on mathematical model must replace the traditional ones as soon as possible. However, the manpower and financial power which are input to the research and application of activated sludge models is very limited in China, so it is just at the primary stage now.This paper's theoretical basis is Monod model, and according to ASM2 and Mass conservation principle, built A/A/O and SBR models. The models contain some differential equations of each model components, and then compiled program in Mat lab and the equations were solved by computer.Model parameters should be corrected before the models are used. This paper corrected the model parameters according to A and B two waste water treatment plant (WWTP) s'data and operation parameters, the value of dynamics parameters and chemo metrics both accorded to the typical value. Parameters correction was conducted based on sensitivity analysis of parameters and steady state simulation, and then , K PHAand K PSof A/A/O were changed from 0.01 and 0.2 to 0.008 and 0.15 respectively ,andμAUT of SBR reduced to 0.81d-1, resulting to the error between real data and simulated result of TCOD, TP ,TN, NH4+-N concentration all were above 15%.The models can be used in not only steady state simulation but also dynamic simulation; the dynamic simulation can express the change of effluent quality when the inflow changed. The paper illustrated the affect of activated sludge models used in technology selection with the example of continuous flow reactor and batch-flow reactor. The waste water plant A was considered as reference, and the paper constructed a new WWTP C, which used SBR designed according to the operation parameters, dynamic parameters and chemo metrics. Subsequently , this paper compared A/A/O and SBR's effluent quality in steady state in the same condition of inflow quality and quantity, and then, simulated the states when changed the quantity ,the value of C/N and the value of C/P, at last, compared this two kind of technology's ability of resistance to impact load. The consequence of simulation indicated this method is feasible.ASM2 can reflect the effect of organics, nitrogen and phosphorus removal of various activated sludge technology more accurately and scientifically than traditional method. It can provide theoretical guidance for the design and selection of activated sludge technology.