Performance of an Ultrafiltration Membrane Pilot System for Treatment of Waste Stabilization Lagoon Effluent

Bali Tourism Development Corporation’s lagoon (BTDC lagoon) has been used for treating wastewaters that come from all facilities available in the Nusa Dua Resort tourist area. Reuse of the lagoon effluent is limited for some applications due to salt and suspended solid contents. Application of an integrated membrane system for improving the water quality of the lagoon effluent which is suitable for various uses is under consideration. In this work an ultrafiltration (UF) pilot performance for possible pretreatment of Reverse Osmosis (RO) was investigated. The results showed that permeate quality was stable (less than 0.5 NTU), regardless of concentrating and diluting retentate in each cycle and fouling for a long duration of operation. However, the water quality obtained with this membrane was not enough to be directly used. The permeate quality obtained from the UF system fulfils the requirement for the optimal operation of reverse osmosis. Moreover, appropriate intermittent-backwash operation was fairly effective to maintain the fluxes at a reasonable level.