METHOD AND APPARATUS FOR REAGENT RECOVERY IN A FLUE GAS PROCESSING SYSTEM

摘要

A system and method is disclosed for recovering reagents that are used in removing contaminants from a flue gas stream. The system and method includes contacting the flue gas stream with reagents such as ammonia and sulfuric acid to create an ammonium sulfate stream. The ammoniated sulfate stream is forwarded to an electrodialysis unit wherein the reagents are regenerated and recirculated back to the system.

主权项

1. A process for removal of gaseous contaminants from a flue gas stream, the process comprising:
contacting the flue gas stream with an aqueous ammonia solution in a direct contact cooling device to form an ammoniated sulfate stream; forwarding the flue gas stream from the direct contact cooling device to a carbon dioxide (CO2) absorption device; contacting the flue gas stream in the CO2 absorption device with an ammoniated solution or slurry to form a CO2 depleted flue gas stream comprising ammonia and a CO2-rich solution or slurry; forwarding the CO2 depleted flue gas stream comprising ammonia to a water wash device to form a CO2 depleted flue gas stream comprising residual ammonia and a used water wash stream; forwarding the CO2 depleted flue gas stream comprising residual ammonia to a direct contact heating device; contacting the CO2 depleted flue gas stream comprising residual ammonia in the direct contact heating device with sulfuric acid to form an ammoniated sulfate stream and a cleaned flue gas stream; releasing the cleaned flue gas stream to atmosphere; and regenerating the aqueous ammonia solution and the sulfuric acid from the ammoniated sulfate streams.