反渗透膜阻垢剂配方优化及其阻垢性能评价

Optimization of Reverse Osmosis Membrane Scale Inhibitor Formulation and Evaluation of Scale Inhibition Performance

摘要: 为解决广西某稀土矿淋洗尾水反渗透膜系统的结垢问题，本研究选用聚羧酸盐(PASP)和有机膦羧酸盐(PBTCA)作为配方成分进行复配制备成了复合阻垢剂。基于静态试验和中试试验研究结果表明，当PASP占比为80%，复合阻垢剂投加量达3 mg/L时，阻垢效率达最高的94.3%；溶度积常数Ksp的指标满足现场水质需求。配方5阻垢剂在钙离子浓缩倍率与膜通量方面的表现优于其他配方，特别是在供水浓缩因子Ki高于3的条件下依然保持稳定。且基于ROSA7.0反渗透模拟软件模拟结果可知，在加入阻垢剂后，CaSO₄和BaSO₄的溶度积常数分别达到360%和3000%，远高于系统要求的控制指标，显现出优异的阻垢性能。此研究结果为稀土矿山尾水的处理提供了有效、低成本的解决方案，促进了水处理技术在生态环境保护中的应用。

Abstract: To address structural issues in the reverse osmosis (RO) membrane system for leaching water from a rare earth mine in Guangxi, this study selected polycarboxylic acid (PASP) and organic phosphonic carboxylic acid (PBTCA) as formulation components to develop a composite scale inhibitor. Based on results from static and pilot-scale experiment, the study found that when the proportion of PASP reached 80% and the composite scale inhibitor was dosed at 3 mg/L, the highest scale inhibition efficiency of 94.3% was achieved. The saturation index (Ksp) met on-site water quality requirements. Formulation 5 demonstrated superior performance than other formulations in terms of calcium ion concentration ratio and membrane flux, especially under conditions where the feedwater concentration factor (Ki) was higher than 3, maintaining stability. Moreover, simulation results using ROSA7.0 reverse osmosis software indicated that after adding the scale inhibitor, the saturation indices of CaSO₄ and BaSO₄ reached 360% and 3000%, respectively. This is far higher than the system’s control indicators, demonstrating excellent scale inhibition performance. The study offers an effective, low-cost solution for treating tailwater from rare earth mine, promoting the application of water treatment technologies in environmental protection.