Influence of Temperature on Activated Sludge Systems

Abstract

The present study aims to determine the influence of temperature in the treatment efficiency of the activated sludge systems. To reach this aim, a simulation study is performed using Matlab® programming language. A biological tank is modelled by the ASM3 (activated sludge model No. 3) and a settling tank is modelled by Takács settling velocity model. For a defined inflow rate and inlet waste water characteristics with the predefined design and operational parameters, the treatment model is simulated. The changes in the kinetic parameters by temperature are estimated from the values given in ASM3 and the dissolved oxygen saturation concentration in water is also concerned as a function of temperature. All the other design and the operational conditions are kept constant during simulations. The simulation algorithm is executed for the temperatures 0°C, 10°C, 20°C, and 30°C. The results show that chemical oxygen demand and total suspended solids reduce slightly with increasing temperature, however, the total nitrogen content in the effluent is changing, first increases for the temperatures 10°C, 20°C, and then decreases for 30°C when it is compared to that of at 0°C. The change in temperature affects mostly the ammonium concentration in the waste water treatment systems.