MBR-超滤-反渗透工艺深度处理化学合成橡胶废水的生产性试验

采用MBR-超滤-反渗透(MBR-UF-RO)组合工艺深度处理化学合成橡胶生产废水。MBR单元水力停留时间(HRT)为5 h，处理生产废水水量1 181 m³/d，进水COD_Cr为158~451 mg/L（平均258 mg/L），出水COD_Cr为5~101 mg/L（平均31 mg/L），出水浊度小于0.2 NTU，出水水质满足超滤进水水质要求。每15天交替进行高、低浓度在线化学清洗可有效控制MBR膜污染。MBR出水与430 m³/d的循环冷却排污水混合后进行超滤和反渗透处理，反渗透出水电导率稳定在30~45 μS/cm，满足企业回用冷却水水质要求。整套废水处理系统废污水回用率为62.8%，回用水的制水成本为4.34元/m³。

Treatment and Reuse of Wastewater in Synthetic Rubber Production by a Full Scale MBR-UF-RO System

The wastewater produced from a rubber synthesis plant was treated by an advanced process of membrane bioreactor-ultra filtration-reverse osmosis (MBR-UF-RO) for reuse. 1 181 m3/d of the production wastewater flowed in the MBR with influent CODCr in the range of 158-451 mg/L (258 mg/L in average). The hydraulic retention time (HRT) of the MBR was 5 h. The MBR effluent, with CODCr in the range of 5-101 mg/L (31 mg/L in average) and turbidity less than 0.2 NTU, could meet the influent requirements of UF. On-line chemical cleaning was carried out with alternation of high and low reagent concentration every 15 d, which effectively controlled the membrane fouling. The MBR effluent was mixed with 430 m3/d of circulating cooling wastewater, and further treated by the UF and RO. The conductivity of the RO effluent was steadily 30-45 μS/cm, which was qualified to be reused as circulating cooling water. The reuse rate of total wastewater treated was 62.8% within the plant, and the operation cost of the advanced treatment was 4.34 RMB/m3.