NOx control by ammonium carbonate and ammonia with hydrocarbons as additives

An experimental study was performed to analyse the effect of hydrocarbon additives, CH4 and C3H8, on NOx reduction by the selective non-catalytic reduction process using ammonia as a reducing agent as well as the use of ammonium carbonate as an independent reducing agent. The experiments were performed in an isothermal flow reactor in which the flue gas contains 500 ppm NOx and 3%O-2 in the temperature range 800-1100 degrees C. A down ward shift of 200 degrees C is observed with the addition of C3H8/NH3 at a molar ratio of 2.0 but with some impaired NOx reduction efficiency. The addition of methane has also exhibited a similar trend; lowering the peak reduction temperature by up to 60 degrees C. The use of ammonium carbonate has shown that up to 78% reduction can be achieved at temperatures similar to 1025 degrees C with a molar ratio of 2.0 thereby demonstrating the potential of ammonium carbonate as a reducing agent for the control of NOx in the flue gases of the combustion sources.