极性-非极性复配捕收剂对难浮氧化煤泥浮选效果的影响及作用机理

Effect and mechanism of polar-nonpolar composite collector on the flotation effect of refractory oxidized coal slime

针对选煤厂入浮煤泥表面氧化程度高、含氧官能团多,导致浮选精煤产率低且灰分高的问题,分别采用柴油、常规极性-非极性复配捕收剂以及自主开发的新型极性-非极性复配捕收剂,进行了浮选试验,并结合接触角测试和吸附量测试,揭示了新型极性-非极性复配捕收剂强化氧化煤泥浮选效果的作用机理。结果表明:采用柴油和常规极性-非极性复配捕收剂进行氧化煤泥的浮选时,浮选效果均较差,难以满足生产要求;而采用新型极性-非极性复配捕收剂进行氧化煤泥浮选时效果较好,且该复配捕收剂更容易吸附在氧化煤泥表面,可显著提高煤泥表面接触角、降低其对水的润湿性,从而提升氧化煤泥浮选效果。同时,针对氧化煤泥采用新型极性-非极性复配捕收剂进行浮选,当捕收剂总用量为1200 g/t时,精煤产率可达74.28%,精煤灰分仅为7.66%。

In response to the high surface oxidation degree,high content of oxygen functional groups,and low yield and high ash content of flotation clean coal,the flotation effect of oxidized coal slime was compared with that of diesel,conventional polar collector and a new polar-non-polar composite collector.The contact angle test and adsorption test method were used to reveal the action mechanism of the new composite collector to strengthen the flotation effect of oxidized coal slime.The mechanism of the new composite collector in enhancing the oxidized coal flotation was revealed.The results show that the flotation effect of oxidized coal slime using diesel and conventional polar collector is poor,which fails to meet the production requirements;while,the flotation using the new polar-non-polar composite collector is favorable,and the agent is easier to be adsorbed on the surface of oxidized coal slime,which significantly improves the coal slime contact angle,reduces its wettability to water,and thus enhances the flotation effect.When the total dosage of the new composite collector is 1200 g/t,the yield of clean coal can be up to 74.28%,and the ash content of clean coal is only 7.66%,in the oxidized coal slime flotation.