介质密度对液固流化床粗煤泥分选效果的影响

Study on Medium Density Affected to Coarse Slime Separation Effect of Liquid-Solid Fluidized Bed

针对工业上液固流化床粗煤泥分选机有效分选粒级窄,对难选煤分选效率低的缺点,开展了介质密度对液固流化床分选效果的影响研究,提出将液固流化床上升清水流改为重介质流。分别在2种上升流流量条件下对3~0.25 mm粗煤泥进行不同上升流流速的液固流化床粗煤泥分选试验。结果表明,液固流化床分选机采用重介质流分选时可将粗煤泥有效分选粒度范围拓宽至3~0.25mm,可能偏差控制在0.05~0.10 g/cm3,在较高上升流流速下精煤灰分可降至9.85%,当要求精煤灰分不大于11%时,精煤产率提高10.21%。

According to a narrow effective separation particle size of a coarse slime separator in the industrial liquid-solid fluidized bed and a low separation efficiency to difficulty washed coal,a theoretical study on the medium density affected to the separation effect of liquid-solid fluidized bed was conducted and upflow clean water flow in the liquid-solid fluidized bed was replaced with heavy medium flow.Un-der the two upflow conditions individually,the coarse slime separation experiments of the liquid-solid fluidized bed with different flow rate were conducted on the coarse slime with particle size of 3~0.25 mm.The results showed when heavy medium flow was applied to the sepa-ration,the separator would effectively have an effective separated particle size scope of the coarse slime expand to 3~0.25 mm and a devia-tion value possibly would be 0.05~0.10 g/ cm3 .Under a high flow rate,the ash content of the clean coal could be reduced to 9.85%.When the ash contents of the clean coal was required not over 11%,the clean coal production rate would be improved by 10.21%.