钢铁企业综合废水处理回用工程实例

Project example of treatment of comprehensive wastewater from iron and steel enterprises

针对钢铁企业综合废水特点及回用水水质要求,采用高效混凝沉淀(带石灰、碳酸钠软化系统)-MBBR生化-过滤预处理和超滤-反渗透双膜法深度处理的组合工艺,处理某钢铁厂全厂综合废水。工程运行结果表明,该工艺处理效果理想,各项运行指标良好,其中预处理出水ρ(CODCr)≤30 mg/L,ρ(SS)<5 mg/L,满足工业新水要求;深度处理出水硬度≤0.03 mmol/L,满足软化水要求。

In view of the characteristics of comprehensive wastewater from iron and steel enterprises and the requirement of reuse water quality, a combined process of efficient coagulation precipitation（with lime, soda ash softening system）-MBBR biochemical technology-filtration pretreatment and ultrafiltration-reverse osmosis double membrane advanced treatment, were used to treat the said kind of wastewater from an iron and steel plant. The engineering operating results showed that, the treatment effect was satisfactory and the running indexes were good. Through the pretreatment, the mass concentration of CODcr in the effluent water were not above 30 mg/L, and the mass concentration of SS was lower than 5 mg/L, which met the requirement of industrial water. The hardness of the effluent water from the advanced treatment unit was not above 0.03 mmol/L, which satisfied the requirement of soft water.