中煤破碎再选试验研究

Experimental Study on Crushing and Recleaning Middlings

以重介中煤为研究对象,通过煤质分析、破碎解离、浮沉、浮选试验,探讨了中煤破碎再选的规律与意义。试验表明,中煤13 mm^6 mm粒级的产率最高,为31.23%,中煤浮沉,低密度级物料含量为9.25%,灰分为7.30%;将密度级1.40 kg/L^1.80 kg/L产物破碎到3 mm以下做浮沉试验,低密度物料产量为8.13%,灰分为7.66%;多次破碎后的煤泥浮选产率升高,灰分升高,破碎程度过大不利于回收合格精煤。

Taking dense-medium middlings as research object,the study explores the rules and meaning of crushing and recleaning the middlings by coal quality analysis,broken dissociation,floating and sinking,and floatation test.The test shows that the highest production rate is 31.23% when the size fraction of the middlings ranges from 13 to 6mm.The content of low density material is 9.25%,ash content is 7.30%.The material at the density in between 1.40 and 1.80 kg/L are broken into particles under 3mm to do floating and sinking test.The production of low-density material is 8.13% and ash content is 7.66%.After multiple crushing,the floatation rate of coal slurry increases and ash content increases too.However,excessive fragmentation degree is bad for the recovery of the qualified clean coal.