煤矿高盐水中反渗透膜化学清洗顺序的优化研究

A Study on Optimization of Chemical Cleaning Procedures for Reverse Osmosis Membranes in High-Salinity Coal Mine Water

摘要: 对于煤矿井下高盐水处理系统中反渗透膜复合型污染的清洗问题，比较传统(碱洗–酸洗)以及优化(酸洗–碱洗–酸洗)这两种不同清洗方式对膜的影响。选取南屯煤矿水处理膜浓缩系统中一级反渗透(RO)系统，采用上述两种方式清洗，观察其清洗前后膜回收率、段间压差及产水量变化情况。结果显示，采用优化方式清洗后一级RO系统回收率达到设计要求，明显高于传统方式。结合煤矿高盐水中硬度大、有机物含量高的实际情况，探讨改进顺序清洗原理：先用酸洗去除无机垢层，便于碱洗去除有机物，然后第二次酸洗去除剩余碱液并且避免再次形成垢层。这种方法大大延长了膜清洗时间间隔，可供类似高盐水处理工程参考借鉴。

Abstract: To address the issue of cleaning composite fouling on reverse osmosis (RO) membranes in underground coal mine high-salinity water treatment systems, this study compared the effects of two different cleaning methods—the traditional method (alkali wash–acid wash) and the optimized method (acid wash–alkali wash–acid wash)—on the membranes. The first-stage RO system in the water treatment membrane concentration system at the Nantun Coal Mine was selected for testing. Both methods were applied, and changes in membrane recovery rate, inter-stage pressure difference, and water production were observed before and after cleaning. The results showed that after cleaning using the optimized method, the recovery rate of the first-stage RO system met design requirements and was significantly higher than that achieved with the traditional method. Taking into account the high hardness and organic content typical of high-salinity water in coal mines, this study explores an improved sequential cleaning principle: first, acid washing is used to remove inorganic scale, facilitating the removal of organic matter during alkali washing; then, a second acid wash removes residual alkali solution and prevents the reformation of scale. This method significantly extends the intervals between membrane cleanings and can serve as a reference for similar high-salinity water treatment projects.