印染废水回用处理的设计实例

Design Example on Treatment and Reuse of Dyeing Wastewater

采用"厌氧水解—缺氧—好氧—二次沉淀—超滤—反渗透"组合工艺进行印染废水的处理回用。运行结果表明,在平均进水COD和色度分别为508 mg/L和1695倍的情况下,COD和色度的总去除率分别为94.2%和98.8%,硬度不超过10 mg/L,铁、锰离子未检出,各项指标均达到HJ 471—2009《纺织染整工业废水治理工程技术规范》中的回用标准。GC-MS分析结果显示,二沉池出水中主要有机物成分复杂,超滤出水中有机物浓度有一定降低,反渗透出水中酸类全部被去除、苯胺类和烷烃类含量明显降低。从染色的白位沾色、手感、颜色和亮度等指标分析,回用水的染色效果远优于工业水。污水处理工程总投资约1×10~7元,设计规模4 500 m^3/d,回用水规模2 500 m^3/d,回用率55%,回用运行成本1.80元/m^3。

The combined process of hydrolysis-A/O-secondary sedimentation-UF-RO was carried out to treat the dyeing wastewater. The operating results show that under the conditions of average inlet COD 508 mg/L and chroma 695 times, the total removal rates of COD and chroma are 94.2% and 98.8% respectively, the total hardness is no more than 10 mg/L, iron and manganese ions are not detected. The quality of the effluent can satisfy the wastewater reuse standard of HJ 471-2009. The GC-MS analysis results show that： In the effluent of secondary sedimentation, the composition of organic compounds is complex; In the effluent of ultrafiltration, the concentration of organic compounds is not decreased significantly; In the effluent of reverse osmosis, acids are removed completely and the contents of aniline and alkenes are reduced significantly. Based on analysis on the indicators of color staining, handle, color and brightness, it is considered that the dyeing effect with the reuse water is much better than that with industrial water. The total invest of the wastewater treatment project is 1 ×10^7 Yuan, the design scale is 4 500 m^3/d, the scale of reuse water is 2 500 m^3/d, the reuse rate is 55%, and the operating cost is 1.80 Yuan/m^3.