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

Compact Membrane Systems, Inc, New Castle DE

Investigators

Abstract

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