Experimental Study on Characteristics of Oxygen-enriched Combustion of Pulverized Coal under Different Combustion Pressures

In order to study the characteristics of oxygen-enriched combustion of pulverized coal and smoke compositions under different combustion pressure, the oxygen-enriched combustion test of pulverized coal under different combustion pressure was carried out by using pressurized fixed bed combustion reaction test system.The results showed that the temperature of combustion center increased with the increase of combustion pressure, when the combustion pressure was more than 3.0 MPa, the maximum temperature of the combustion center no longer increased significantly, it maintained at about 750 ℃; with the increase of pressure, the ignition time of pulverized coal was shortened, the burning time decreased at first and then increased, when the combustion pressure was more than 3.0 MPa, the ignition time and burning time of pulverized coal were no longer change significantly with the increase of combustion pressure; with the burning of pulverized coal, the concentration of O₂ decreased at first and then increased, and finally reached the intake air concentration, when the combustion pressure was more than 3.0 MPa, the concentration of O₂ decreased rapidly in the first 3 min, indicating that the pulverized coal burned vigorously under such circumstances; the concentration of CO₂ decreased at first, then increased and then decreased to reach the intake concentration; the concentration of CO increased at first and then decreased, and with the increase of combustion pressure, the concentration of CO produced during combustion decreased.