Study On Flotation Characteristics Of Argillaceous Coal By Gradation Optimization

Flotation is undoubtedly the most important and effective fine coal processing technique,but it seriously decreased the efficiency of flotation and plagued a lot of coal preparation plant that some coarse mineral impurities in the water are very apt to be slimed,so how to improve the argillaceous slime flotation effect is a problem urgently to be solved.So research argillaceous slime characteristics and influence of high ash slime on the coal flotation to improve the flotation effect,which is a very meaningful subject.Based on basic properties of the raw coal of the Malan 02#,the flotation reagent system of Malan 02#was optimized,the influence of gradation optimizaion on the flotation effect and characteristics by content of<0.045mm fine slime was discussed in detail,and flotation mechanism was explored through the XRD,contact angle,zeta potential and particle size distribution analysis,the following conclusions were drawn:1.Through optimization of the flotation reagent system,the best reagent system of Malan 02#as follows:the best combination is kerosene as collector and sec-octyl alcohols as frothor,whose dosage were respectively 800g/t of dry slimeand 160g/t of dry slime.2.The effect is different by high ash fine slime in different grade.It was achieved the best floatation effect and the highest floatation index that adding 35.1%fine mud into the 0.5～0.25mm grade coal slime,adding 32.3%into the 0.25～0.125mm grade,adding 52.3%into the 0.125～0.074mm grade and adding 32.8%into the 0.074～0.045mm grade.3.Adding 16.9%fine mud into the Malan 02#raw coal,it will cause great positive influence to the coal slime flotation,but over the contentmit will seriously effect the function of flotation.Experiments prove that the greater fine mud content,the lower combustible material recovery.The fine mud content is greater than a certain value,the clean coal yield fell sharply,concentrate ash recovered after fall,the improved floatation index increased first and then fell back.4.When fine mud is less than the best content,the flotation rate constant of 0.5～0.25mm and 0.2-0.125mm grade declines sharply,and more than the quantity,it declines more smoothly,but the flotation rate constant of 0.125～0.074mm and 0.074～0.045mm grade of declining trend is relatively flat,within 0.004s-1.5.Fine mud fraction pollute clean coal of 0.5～0.25mm grade in the hole flotation process,fine mud fraction pollute flotation clean coal of 0.25～0.125mm and 0.074～0.045mm grade is mainly in the early stages,the flotation effect of 0.125～0.074mm grade itself is bad,there are undissociated mineral combination,adding part of fine mud can improve flotation effect.6.Total EDLVO potential of coal particles and high-ash slime is negative,so it is mainly attract each other.It is say that high-ash slime easily attached to the coal particles,which would adversely affect the flotation.The new technology of gradation optimization for argillaceous slime flotation is reasonable and effective.Through the classification method of slime to adjust the appropriate portion of the<0.045mm material of fine mud without changing the properties of slime and component conditions,the ash of clean coal can be effectively reduced by flotation.