钢铁工业综合废水处理回用工程实例

Engineering Project of Comprehensive Wastewater Treatment and Reuse in the Iron and Steel Industry

为提高厂区废水水资源利用率,某钢铁公司采用"格栅+高效沉淀池+V型滤池+超滤(UF)+一级反渗透(RO)+二级RO+电去离子(EDI)"工艺处理和再生回用其生产综合废水,产水有软水、除盐水和超纯水等。实际运行结果表明,该工艺设计合理,运行稳定,实现了72%~80%的高回收率废水回用;其中UF系统产水SDI15<2.5,一级RO、二级RO、EDI产水电导率分别为<30、<2.5、<0.06μS/cm,特别是其产水电阻>17 MΩ·cm,达到GB/T 6682-2008一级超纯水水质要求,其它各项产水指标均能够满足不同生产单元对于不同品类水质的需求,实现了厂内分区分质供水。

In order to improve the utilization rate of wastewater resources, a steel company used the technology of "grille + high efficiency sedimentation tank + V-filter + UF+ first-pass RO + second-pass RO + EDI" for treatment and recycling its comprehensive production wastewater, the produced water included soft water, demineralized water, ultra-pure water, etc. The practical operation results showed that, the process design was reasonable, the operation was stable, and the wastewater reuse with high recovery rate of 72%~80% was realized. Among them, the SDI15 of UF system effluent was less than 2.5, the effluent conductivity of first-pass RO, second-pass RO, EDI were less than 30, 2.5, and 0.06 μS/cm,respectively, especially the resistance of its effluent was more than 17 MΩ·cm, which met the first level standard of ultrapure water of GB/T 6682-2008. All other effluent indicators could meet the needs of different production units for different types of water quality, realizing the water supply by area and quality in the factory.