煤泥“2+2”分选工艺的问题分析及优化试验

Problem analysis and optimization test for “2 + 2”coal slime separation process

针对煤泥"2+2"分选工艺在工业应用中处理粗煤泥灰分较高和(或)高灰细泥含量大的煤泥时,存在粗精煤泥和二次浮选精煤灰分偏高、重介精煤"背灰"的问题,提出在该工艺中引入TBS分选粗煤泥和旋流微泡浮选柱作为二次浮选设备的工艺技术,通过试验进行了验证。试验结果表明:利用TBS不仅分选出合格的粗精煤泥,而且数量效率达85.01%,可能偏差E p=0.069;旋流微泡浮选柱作为"2+2"分选工艺的二次浮选设备比常规浮选机优势明显,当煤油用量1 000 g/t,仲辛醇用量125 g/t时,浮选柱比浮选机的精煤灰分降低3.76%,精煤产率增加4.10%,浮选完善指标提高9.97%。

High clean coal ash problem in ＂2 ＋2＂ coal slime separation process, usually seen in high ash coarse slime and high ash fine slime beneficiation, may contributes to clean coal loss, because heavy medium cyclone clean coal should be controlled at relatively low level to meet the total ash requirement. In order to tackle the problem, Teetered Bed Separator and cyclonic micro-bubble flotation column were introduced to the ＂2＋2＂ process to separate coarse and fine coal slime respectively. The results demonstrate that, Teetered Bed Separator can recycle qualified clean coal at high quantity efficiency and low Ep value （85.01% and 0. 069 respectively）. Cyclonic micro-bubble flotation col- umn, used as the second stage flotation column, is able to treat high ash fine slime at better performance than conven- tional flotation cell. At the kerosene dosage level of 1 000 g/t and the octanol dosage level of 125 g/t, column flotation is 3.76% lower in clean coal ash,4.10% and 9.97% higher in clean coal yield and flotation perfection index respec- tively than conventional cell flotation.