EVALUATION OF TWO-STAGE FILTRATION SYSTEMS IN DRINKING WATER TREATMENT

Behaviour of a two-stage filtration system used for turbidity removal. Comparison of the performance of an upflow coarse sand filter/rapid sand downflow filter system (UCSF system) with the upflow gravel filter/rapid sand downflow filter system (UGF system). Both systems are technically feasible processes to treat raw water with turbidity lower than 20 NTU and true colour below 50 HU.