溶解性硅化合物对反渗透系统的影响及控制

Impact of Dissolved Silicon Compound on Reverse Osmosis System and Control

在炼油化工污水回用处理过程中,由于废水中的溶解性硅浓度较高,使反渗透膜表面形成了致密的硅垢,严重影响反渗透膜的长周期安全运行,且给反渗透膜的清洗工作带来了很大困难。着重对污水处理系统各单元的水质情况及已结垢反渗透(RO)膜表面进行系统分析,并通过絮凝沉降实验,分别向污水中投加氨水、石灰水或氢氧化钠固体等优化调节其pH值,使其最大限度地降低污水中的溶解性硅浓度,形成了一套可行、有针对性、易操作的膜结垢控制方案。在装置技术改造期间实施了这套方案,达到了预期的试验效果。

In the re - utilization of waste water in petroleum refineries and petrochemical plants, the compact of silicon foul on the surface of reverse - osmosis membrane due to higher concentration of dissolved silicon in the waste water has seriously affected the long - term safe operation of the reverse - osmosis membrane and created great difficulty for the cleaning of the reverse - osmosis membrane. Based upon the analysis of waste water quality in waste water treatment system and fouled surface of reverse - osmosis and thrnugh the floeeulation experiment, liquid ammonia, lime water or solid sodium hydroxide was added to the waste water to optimally adjust its pH value and minimize the concentration of dissolved silicon in waste water. As the result, a feasible, effective and easy - operating membrane fouling control process has been developed ; The predicted objectives have been reached when the process was applied in the technical revamping of the project.