Development of an electrochemical membrane process for removal of sulfur oxides/nitrogen oxides from flue gas.

摘要

Vast reserves of coal in the United States provide a stable source of fuel for the future. Standard combustion of coal in an electric generating station releases all constituents of coal and causes pollution problems that must be mitigated. Of particular concern are the oxides of sulfur, which react in the atmosphere to form acid rain. The state-of-the-art technology for controlling sulfur dioxide emissions is the wet limestone scrubber, which is expensive and generates large quantities of waste. An alternative approach, investigated here, separates the sulfur oxides from the flue gas and generates a saleable by-product. An electrochemical membrane performs the separation, with the assistance of an applied electric field.;The investigation focused on two of the materials in the system, the electrolyte support (matrix) and the electrodes. Chemical stability testing and particle size distributions identified several suitable matrices, particularly Si;These components were assembled into the bench-scale removal cell for performance testing. Simulated flue gas of 0.3% SO;A preliminary economic evaluation of the electrochemical membrane separation process was performed. An optimal design using 25 mA/cm