Combustion and self-ignition characteristics of Shengli lignite with different drying degrees
Hao Junzhong
Wang Zhichao
Yao Wei
Abstract：In order to investigate the change of combustion and self-ignition characteristics of high moisture lignite under different drying degrees,a one-dimensional flame combustion furnace,a pulverized coal ignition temperature examining furnace and a coal self-ignition analyzing apparatus were used to test the combustion performance of Shengli lignite.Results show that the ignition temperature decreases with the increase of the drying degree,while increases with the rising of the air/coal ratio.The fineness of pulverized coal will also affect the ignition temperature.When burning with the drying lignite,a higher primary air rate should be adopted to improve the safety of coal pulverizing system.Shengli lignite raw coal and the dried samples are very easy to be burn-out,and the burn-out rates are above 99.4％.The change of moisture has little effect on the burn-out rate.The suggested operational oxygen supply is approximate 3.5％ for burning the Shengli lignite and its 20％ moisture drying lignite.The lignite with deeper drying degree and smaller particle size is easier to be self-ignition.The excessive drying with the moisture content less than 20％ will bring higher risk of self-ignition.
Keywords：Shengli ligniteself-ignitionignition temperatureburning-out rate
Publication Date：2017-01-01