Conductive Spacers to Limit RO Membrane Scale Formation

限制 RO 膜水垢形成的导电垫片

• 批准号: 544056-2019
• 负责人: DeLannoy, CharlesFrançois
• 金额: $ 1.82万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=680389
• 关键词: Conductive; Spacers; Limit; RO; Membrane

Mining extraction produces large quantities of wastewater, oftentimes with high salt concentrations. This brine must be treated before disposal into the environment. The technology of choice for salt-water separations is reverse osmosis (RO) membranes. However, RO membranes foul quickly under the high salinity conditions of mining wastewaters. The mining wastewaters of concern have high concentrations of calcium with excess sulfate. Under these conditions, a calcium sulfate (gypsum) scale composed of dense and sharp mineral precipitates form on the membrane surface. These scaling layers block trans-membrane water flow, reduce membrane ion selectivity, and can damage membrane surfaces. Electric fields have been shown to disrupt the formation of mineral scale. Positive applied electric potentials, for example, can prevent the deposition of Calcium ions on the membrane surface, thereby limiting the formation of gypsum. In preliminary research, electrically conductive membranes have shown promise for their ability to limit the formation of gypsum scale. Electrically conductive membranes, however, have only been fabricated at the lab scale and are far from commercial development. A simpler solution is to replace the polymeric spacers used in membrane modules with electrically conductive materials to which potentials can be applied. Our research will investigate the application of electric potentials to electrically conductive spacers as a means to reduce or limit mineral scale formation. We will investigate the impact of different applied potentials ranging between +0.5 V and 3.0 V, as well as different electrically conductive metal spacer materials (Al-Mg, stainless steel, and Cu) and metal spacer gauges.

采矿提取会产生大量的废水，通常盐浓度高。在处置环境之前，必须对此盐水进行处理。盐水分离的首选技术是反渗透（RO）膜。但是，在采矿废水的高盐度条件下，RO膜迅速犯规。所关注的采矿废水具有高浓度的钙，过量的硫酸盐。在这些条件下，硫酸钙（石膏）尺度由膜表面形成密集和尖锐的矿物沉淀物组成。这些缩放层阻止跨膜水流，降低膜离子的选择性，并损坏膜表面。电场已被证明破坏了矿物量表的形成。 例如，施加阳性的电势可以防止钙离子在膜表面的沉积，从而限制了石膏的形成。在初步研究中，导电膜对限制石膏量表形成的能力表现出了希望。但是，导电膜仅是在实验室规模上制造的，远非商业开发。一个简单的解决方案是用可施加电势的磁导电材料代替膜模块中使用的聚合物垫片。我们的研究将调查电势在电导垫片中的应用，以减少或限制矿物质规模的形成。我们将研究范围+0.5 V和3.0 V之间的不同应用电势的影响，以及不同导电的金属间隔材料（Al-MG，不锈钢和CU）和金属垫片测量值。