A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 1981

One common pollution abatement method for treating bio-degradable wastes is activated sludge process . In this study , a model is proposed for both unsteady and steady state kinetics of bio-oxidation in activated sludge reactors. It is HD extension of earlier models in which the reactor to be a series of tanks. The present study develops a model of the clarifier bud then combines the two models to simulate the system. This has not done before. The model presented here was studied using a digital computer(IBM 3031/6), with responses to several inputs evaluated. Strategies used in practice, such as sludge recycle rate control were first examined. The simulation results for different parameter values, e.g. degree of mixing, recycle ratio, number of tanks and other factors give results similar to previous studies. Responses to various input distributions in the proposed model were studied and trends similar to those in the literature were obtained. Results of simulation of the proposed model were obtained. Results of simulation of the proposed model were also compared with experimental data of GOODMAN & ENGLANDE (1974) and TUAN et al. (1980) Our model seems to give results closer to the experimental data than the previous models.