潮湿褐煤干法分选实验研究

为提高空气重介质流化床对入料煤水分的适应性,以热气代替常温空气改善流化床对褐煤的分选效果。采用可能偏差Ep为评价指标,研究了热态空气重介质流化床的干燥温度、干燥时间和风量对褐煤分选效果的影响。结果表明:干燥温度为30~50℃时,干燥温度越高,Ep越低;干燥时间为1~5 min时,干燥时间越长,Ep越低,超过3 min后,Ep降低缓慢;风量为8~12 m3/h时,风量增大,Ep先降低后升高。煤样表面水分越高,干燥温度、干燥时间和风量变化对Ep影响越显著。表面水分1%的褐煤,干燥温度50℃、干燥时间5 min、风量10 m3/h时,褐煤分选效果最好,Ep可达到0.022g/cm3。实验证明热态空气重介质流化床可用于分选潮湿褐煤。

Experimental study of dry preparation of moist lignite

In order to improve the adaptability of air dense medium fluidized bed on different coal moisture,the hot air was blown to the flu-idized bed instead of the air at ordinary temperature,so the lignite can be separated efficiently.The effects of drying temperature,drying time and air flow in fluidized bed were investigated with ecart probable moyen Ep .The results showed that when the drying temperature ranged from 30 ℃ to 50 ℃ ,the higher the drying temperature,the lower the value of Ep .When the drying time were between 1 minute and 5 minutes,the longer the drying time,the lower the value of Ep ,and Ep decreased slowly after drying 3 minutes.When the air speed were between 8 m3 / h and 12 m3 / h,Ep reduced first,then rose with air speed increased.The higher surface moisture of the coal sample,the more significant influence of drying temperature and time,air volume on Ep .The Ep was 0.022 g/ cm3 when the drying temperature was 50 ℃ ,the drying time was 5 minutes,and the air flow for coal sample of 1% surface moisture were 10 m3 / h.