SBIR/STTR Phase II: Development of Stable Membrane-Based Gas-Liquid Contactors for SO2 Removal from Flue Gas

这项小型企业创新研究第二阶段项目将展示膜基气液接触器在减少烟气中二氧化硫排放方面的增强性能。烟气流中存在的二氧化硫由于参与酸雨的形成而导致森林砍伐和对作物和财产的损害。在第一阶段，Compact Membrane Systems, Inc. （CMS）开发了一种无孔含氟聚合物复合膜，设计用于膜基气液接触器，使用水吸收溶液洗涤烟气中的二氧化硫。这种膜的设计是为了克服传统微孔支架的主要缺点，即（通常）含水吸收剂逐渐湿润微孔基底，在某些情况下，盐在液气界面沉淀。除了膜接触器的所有操作优势外，CMS膜还能持续提高SO2的去除效率。在第一阶段，该膜渗透SO2，在相同的条件下，即使不优于传统的微孔膜接触器，也没有表现出性能损失，即使暴露于酸化的二氧化硅悬浮液中。第二阶段将扩大该过程，采用大型中试接触器，研究吸收剂再生技术，在中试燃烧器上演示整个过程，并证明与现有系统相比，CMS系统具有更高的效率和经济性。对于矿石加工商、纸浆和造纸工业、许多石油和天然气加工商（特别是那些必须处理来自气体脱硫过程的尾气的加工商）、使用煤作为化石燃料的发电厂等来说，膜基气液接触器减少烟气中二氧化硫排放的增强性能具有相当大的意义。

This Small Business Innovation Research Phase II project will demonstrate theenhanced performance of membrane-based gas-liquid contactors to abate SO2emissions from flue gas. SO2 present in flue gas streams leads to deforestation anddamage to crops and property as a result of its participation in the formation of acidrain. In Phase I, Compact Membrane Systems, Inc. (CMS) developed a nonporousperfluorocopolymer composite membrane designed for use in membrane-based gasliquid contactors to scrub flue gas of SO2 using an aqueous absorbent solution. Thismembrane is designed to overcome the major drawbacks of conventionalmicroporous supports, i.e. progressive wetting out of the microporous substrate bythe (typically) aqueous absorbent and in some instances salt precipitation at theliquid-gas interface. In addition to all the operational advantages of membranecontactors, CMS membranes result in sustained improved SO2 removal efficiencies.During Phase I it was demonstrated that this membrane permeated SO2, scrubbed aflue gas simulant gas stream of SO2 as well as if not better than a conventionalmicroporous membrane contactor under identical conditions, and showed no loss inperformance despite exposure to an acidified silica suspension. Phase II will scale-upthe process to employ large pilot-scale contactors, study absorbent regenerationtechnologies, demonstrate the whole process on a pilot-scale combustor, anddemonstrate that the CMS system offers better efficiencies and economics of flue gasremoval compared to existing systems.The enhanced performance of membrane-based gas-liquid contactors to abate SO2emissions from flue gas is of considerable interest to ore processors, pulp and paperindustries, many oil and natural gas processors (particularly those which have totreat tail gases from gas sweetening processes), power plants employing coal as afossil fuel, etc.