COMPUTER-AIDED SIMULATION OF SLOW SAND FILTER PERFORMANCE

Although the modelling of deep bed filtration has progressed considera bly in recent years, almost no attention has been given to simulating the process of slow sand filtration. The exception, to date, is the wo rk of Woodward and Ta (1988) who have attempted to simulate slow sand tilter performance via a simple, empirical headless model; however, th is model is not deterministic in nature and cannot predict filtrate qu ality nor the spatial headless development with the filter. This paper describes the development and calibration of a computer-based numeric al model based on assumed filtration coefficient and headless relation ships. The model structure includes a simple representation of biomass development but ignores the possible influence (currently uncertain) of a Schmutzdecke-surface skin. It is concluded that the spatial and t emporal headless development within the media bed can