Experimental Investigation On Combustion Characteristics Of Purge Gases

Supported by the Important Basic Research Development Plan of Nation (plan of 973)《The Basic Research of Gasification Gas and Pyrolysis gas Produce Synthesis Gas in Poly-generation Application》, experimental investigation basic characteristics of purge gas witch is simulated using CH₄,CO and H₂ according to certain percentage preparation, accumulating basic data and regularity of combustion of purge gas. The guidance is provided for engineering combustion of purge gas.The basic theory combustion of methane, carbon monoxide, hydrogen, and the physicochemical property of purge gas are introduced in this paper. The system of combustion experiment of purge gas is established. The influence of excess air coefficient on temperature of combustion, combustion products of purge gas is studied.The temperature of combustion of purge gas gradually decline in the radial direction, arise first and descend later near chamber wall and gradually decline other places along the axial direction, chamber outlet temperature less than 500℃. When excess air coefficient (a) are in the range of 0.8-1.3, the oxygen concentration continually increased and the carbon dioxide density increased and then decreased along the axial direction, the peak value appeared at a=0.95(excess air coefficient).It is found through experiment that the concentration of NOx increased rapidly atα<0.9(excess air coefficient), appeared valley value atα=1.05(excess air coefficient) and appeared peak point atα=1.1 (excess air coefficient). The concentration of NOx decreased obviously before valley value, and decreased slowly after peak value. The excess air coefficient has minimum value and best value in generative process of NOx, The excess air coefficient is determined by the concrete condition.