Study On Modelling And Simulation Of Anaerobic Biofilter For Municipal Wastewater Treatment

With the development of industry and agriculture and the increasing of population in cities, the serious scarcity of water and water pollution were noticed. With the growing requirements on effluence quality and treatment efficiency, and the limitation on treatment cost and consumed energy, the traditional way to design and manage the wastewater treatment plant by experiences and standards can not meet the demand of rapidly developing wastewater treatment cause. The main advantages of using anaerobic biofilter are their compactness, low sludge production and energy consumption. So it won more and more the experts attention. So developing mathematical models and corresponding simulating software for wastewater treatment process has been coming to be an inevitable tendency and it will improve the design and operation efficiency.A mathematical model is based on analysis of the main effects on the up-flow anaerobic biofilter developed, which can characterize not only the substrate removal dynamics but also the gradual biofilter clogging. It simulates dynamic up-flow anaerobic biofilter response to flow rate, the substrate and suspend solid concentration in the influent, diameter, surface area and porosity of support medium. The model considers three aspects: the biological reaction, deep filtration and hydrodynamics. Especially, it is the first time to introduce the deep filtration into the model describe.A numerical finite difference scheme is employed to solve the nonlinear partial differential algebraic equations, using Newton's iterative technique. It programmed by the software of MATLAB. A sensitivity analysis was performed on model parameters to investigata the sensitivity of the model parameters on biofilter performance. The parameters, maximum growth rate, effective diffusivity and biofilm thickness have a positive affect on biofilter performance as the values increase, but the half-saturaction constant is opposite.Applying the model to the experimental up-flow anaerobic biofilter. Contrast the simulated and experimental data, it proved the model could simulate availably the performance of the biofilter, which is operated on different loading and environment. The model would be used as an effective tool for the exited wastewater treatment plants operation management and the biofilter optimal design.