Application of microfiltration with a novel fouling control method for reuse of wastewater from a large-scale resort complex

A study was conducted to investigate the treatability of a new microfiltration system utilizing agitator-induced flushing of the membrane to prevent fouling for wastewater reclamation. A hollow-fiber membrane was immersed in the tank and permeate was filtered through the membrane by intermittent suction using a pump. Influent from the large-scale resort complex was used. In the tank an agitator was operated at 350 rpm, with clockwise (4 s) - stop (1 s) - counter-clockwise (4 s) rotation cycle. Membrane pore size, permeate flux and suction mode were studied. The optimal operational setting was determined to be 0.02 m/h flux, with 10-min suction and 2-min idle permeate pumping cycle. This setting was capable of 77 days of continuous operation without chemical cleaning. Below 20 mg/L of COD, 3.5 mg/L of TOC, 0.2 NTU of turbidity and no suspended solids were contained in the effluent. This system was adequate for the reuse of wastewater for secondary applications such as in toilet flushing.