Low concentration gas metal fiber combustion technology and its experimental study
In order to reduce the emission of low concentration gas in coal mines,reduce the air pollution,and achieve the national goal of energy conservation and emission reduction,the study on the combustion of low concentration gas metal fiber was carried out.The advantages of metal fiber combustion for low concentration gas were analyzed.Based on the flammable and explosive characteristics of low concentration gas,dust and moisture contained in the gas and other factors,the bundled iron-chromium-aluminum long fiber knitted fabric containing rare metal yttrium was selected to make low concentration gas metal fiber burner.The burner structure,thermal load and metal fiber radiation area were designed.Finally,combustion experiments were carried out.The results showed that when low concentration gas was burned using a metal fiber burner,the lower limit of methane volume fraction was 5.0%.The temperature inside the metal fabric of the metal fiber burner was negatively correlated with the combustion intensity.The temperature inside the gas flow distribution plate of the metal fiber burner increased first and then decreased with the increase of combustion intensity.When the gas methane volume fraction was 8.1%and the combustion intensity was 400 kW/m2,the temperature inside the gas flow distribution plate was the highest,reaching 248℃,which was far lower than the thermal self-ignition temperature of methane.Therefore,it was unlikely to backfire when using metal fiber burner to burn low concentration gas.