Patent ID: 6403046
Filing Date: 2002-06-11
Classification: B01D,F23J

Abstract:
In a sectioned system for removing NOx from one or more flue gas streams from fossil fuel burning facilities, and wherein a first section of the system reduces NOx by injection of a urea based solution in a form, location and operating temperature of the flue gas stream, appropriate for selective reduction of NOx with urea, and wherein a second section of the system communicates with a flue gas stream at a location and flue gas operating temperature appropriate for the reduction of NOx with gaseous ammonia, the improvement comprising:a storage facility, for storing urea solution, which is operative as a common source for the urea based solution used in the first section, and for the gaseous ammonia provided for the second section; first conduit means for selectively directing a portion of the stored urea solution to a conversion system; said conversion system for converting at least a portion of urea solution supplied thereto to a gaseous mixture containing ammonia, and leaving a remaining portion of the solution; second conduit means for directing such a gaseous mixture containing ammonia to said second section, as a source of gaseous ammonia for NOx reduction; and third conduit means for continuously directing such remaining portion of the solution for integration with urea based solution.