Graded flotation of entrained-flow coal gasification fine slag and EDLVO analysis
Coal gasification fine slag(CGFS)is a solid waste produced in the process of coal gasification,and its resource utilization problems restrict the green and low-carbon development of coal chemical industry.The characteristics of CGFS,such as fine particle size,small mass and low momentum,cause serious entrainment of high ash content fine particles in foam products during flotation,which affects the quality of flotation concentrate.In this paper,the graded flotation process was used to optimize the flotation conditions of CGFS.The carrier flotation process was used to study the effect of carrier ratio on the flotation efficiency of CGFS with a particle size of+0.045mm.The research results indicated that increasing the carrier ratio could significantly enhance the flotation effect.Under the designed experimental conditions,the flotation perfection index reached to 71.53％,and the combustible recovery was 87.57％,which was 20.57％higher than the conventional flotation without carrier.The interaction force between carrier and CGFS was calculated using EDLVO theory.During the carrier flotation process,the electrostatic force between carrier and CGFS showed attraction,which was prone to adhesion behavior,promoting the aggregation of fine particles and improving the flotation effect.The flocculation flotation method was adopt for-0.045mm particle size.With the increasing of flocculant dosage,the flotation perfection index of-0.045mm size CGFS showed a trend of increasing first and then decreasing,the highest flotation perfection was 39.61％,and the ash content of flotation concentrate was not significantly reduced.The flocculation analysis showed that the addition of flocculant promoted the non-selective agglomeration between particles,which led to the high ash content of the flotation concentrate,and the selective flocculation effect should be further improved subsequently.The CGFS classification flotation process proposed in this study has certain theoretical guidance for reducing the entrainment of fine and high ash content particles on flotation,and further improving the quality of refined carbon products.
coal gasification fine slagflotationclassified flotationcarrier flotationflocculation flotationEDLVO theory
万方数据
维普
