新型复合捕收剂强化细粒低阶煤浮选机理研究

Study on Flotation Mechanism of Fine Low Rank Coal Enhanced by New Composite Collector

低阶煤表面含有丰富的含氧官能团且孔隙发达,用传统非极性烃类油浮选低阶煤时药剂耗量大、可燃体回收率低,针对此问题,将柴油、脂肪酸及其酯类化合物按照一定比例复配,制备了一种新型复合药剂(DK1),并考察了其对低阶煤浮选的效果。通过接触角测量、诱导时间分析以及颗粒-气泡间临界脱附力测量等方法,揭示了新型复合捕收剂强化低阶煤浮选机理。结果表明:同等药剂用量下,DK1可燃体回收率是柴油的2~4倍,同时精煤灰分普遍低于柴油1~4个百分点。新型复合捕收剂处理过后的煤样接触角更大,诱导时间明显缩短至10 ms以内,颗粒-气泡间跳入黏附力、临界脱附力的作用程及其大小均有不同程度增加。DK1的柴油与活性物质产生协同作用,有效覆盖低阶煤表面,显著提高了低阶煤的可浮性,降低了药耗,DK1药剂用量仅为柴油的1/8。

The surface of low rank coal is rich in oxygen-containing functional groups and developed pores.When low rank coal is floated with traditional non-polar hydrocarbon oil,the reagent consumption is large and the recovery rate of combustible product is low.To solve this problem,a new type of composite reagent(DK1)was prepared by compounding diesel,fatty acids and their esters in a certain proportion,and its effect on the flotation of low rank coal was investigated.Through the contact angle measurement,the induction time analysis and the measurement of critical desorption force between particle and bubble,the flotation mechanism of low rank coal enhanced by new composite collector was revealed.The results show that under the same dosage of reagent,the recovery of combustible product of DK1 is 2~4 times that of diesel,and the ash content of cleaned coal is generally 1~4 percentage points lower than that of diesel.The contact angle of coal sample treated by the new composite collector is larger,the induction time is significantly shortened to less than 10 ms,and the action range and size of jump-in attachment force and critical desorption force between particles and bubbles increase in varying degrees.The diesel oil of DK1 has a synergistic effect with active substances,effectively covering the surface of low rank coal,significantly improving the floatability of low rank coal and reducing drug consumption.The dosage of DK1 is only 1/8 of that of diesel oil.