Advanced Treatment of Chemical Wastewater by Using a Combination of Ultrafiltration and Reverse Osmosis System

The purpose of this paper was to investigate the application of ultrafiltration/reverse osmosis (UF/RO) for advanced wastewater treatment. Full-scale tests were set up for investigation in Yuntianhua Co.Ltd, Yunnan, China. The performances of turbidity, residual chlorine, conductivity and various ions were studied. The results suggested that the removal efficiency of turbidity was above 98.20%. Additionally, the average value of Silting Density Index (SDI) and residual chlorine of effluent of UF process were less than 1.80 and 0.06mg/L, respectively. However, its removal efficiency was limited by membrane fouling. And this system needed to be backwashed periodically to maintain high removal efficiency. Hardness and scale-forming ions could be decreased effectively by RO. The RO membrane fouling could be avoided by adjusting pH (7.0-7.5) and dosing scale inhibitor (MDC150, 4.00-5.00mg/L). Finally, the effluent of the UF/RO system can be reused as the cooling water or supply water for low-pressure boiler equipment.