GENERAL-MODEL FOR BIOLOGICAL NUTRIENT REMOVAL ACTIVATED-SLUDGE SYSTEMS - MODEL PRESENTATION

The development of a general model for biological nutrient removal in activated sludge systems is discussed. The general model is a mechanis tic model based on the International Association on Water Pollution Re search and Control (IAWPRC) (now IAWQ) model for carbonaceous energy r emoval, nitrification, and denitrification (Activated Sludge Model No. 1 [ASM1]), and the Wentzel et al. (1989a and b) model for biological phosphorus removal, with a number of modifications. A fermentation pro cess has been included for the conversion of readily biodegradable che mical oxygen demand (COD) to short-chain fatty acids (assuming a loss of COD from the system). Hydrolysis of enmeshed slowly biodegradable C OD under anoxic and anaerobic conditions has been incorporated, as wel l as anoxic growth of polyP organisms. These modifications and others are discussed in this paper. The matrix representation and a descripti on of the model processes are also presented, as well as a brief outli ne of influent wastewater characterization.