Effect Of The Foaming Agents Properties By The Combination Of Ultrasonic Emulaication And Chemical Modification

In coal flotation, foaming agent’s performance not only affects the qualityand quantity of bubble, but also affects the collision behavior betweencoal particles, and promotes the coal particles adhesion on the bubble inthe foam layer to separation. At present, coal preparation plant site’s commonfoaming agent are octanol, fusel,2#oil and so on, but these foaming agent,especially natural foaming agent, their source is limit, and due to poor foamingperformance, the bad foam stability and other factors, the flotation effect is notideal. The author through ultrasonic emulsification, chemical modification andother testing method, improves the octanol as foaming agent’s utilization, anddevelop new agents on the basis of series of study. The results show that,after ultrasonic emulsification, the foaming agent utilization rate is improved,the flotation efficiency is also improved; after chemical modifying, the newagents’ flotation efficiency is also greatly improved; and the flotation efficiencyof foaming agent through synergistic effect of ultrasonic emulsification andchemical reaction is higher than that through independent effect of ultrasonicemulsification or chemical function. The conclusions are as follows:Conclusion one: Through industrial analysis, XRD and granularity analysison the testing coal sample, shows that, Jincheng Anthracite sample containskaolin, resulting in a serious coal particle mud, is not conducive to the flotation;in coal sample, extremely fine-grained level component which less than0.054mm is more, about30%, and the ash is very high,33.72%; Jincheng Anthracite is medium floatability coal.Conclusion two: The best ultrasonic emulsification time: sec octyl alcoholis8min, A foaming agent is4min, B foaming agent is4min; the best ratio offoaming agent and water:the octanol: water=1:5, A foaming agent: water=1:2,B foaming agent: water=1:1; the best emulsifying strength: all are the biggest,the solubility of three kinds of foaming agent increases with ultrasonic intensity;the best horn length: all are the longest, the solubility of three kinds of foamingagent increases with the growth of horn length. Octanol and other two foamingagents can be emulsified in suitable condition, but the emulsifying effect is notstable; after the addition of stabilizer, the emulsion stability can be maintained.Conclusion three:(1)By the method of the adjacent benzene two phthalicanhydride esterification modification sec octyl alcohol’s flotation clean coalyield increased by8%, the effect is obvious, but the A foaming agent, the Bfoaming agent after esterification, their flotation performance did not change,that this modified method is effective only for octanol;(2)Sec octyl alcohol,A foaming agent, B foaming agent modified by sulfuric acid, theirflotation clean coal yield increased by10%,9%,13%respectively, the effect isobvious, that this modified method is effective;(3) Sec octyl alcohol, A foamingagent, B foaming agent modified by phosphoric acid acidification, gettingcorresponding foaming agent, their flotation clean coal yield increased by5%,6%,7%respectively, the effect is obvious, that this modified method is effective;Octanol, A, B’s best esterification condition is:esterification time is5h, selectboric acid as catalyst, cyclohexane as solvent, alcohol and acid anhydride ratio is1:1.6, esterification temperature is100℃.Conclusion four: Sec octyl alcohol, A foaming agent, B foaming agent,modified by emulsification or chemical modification alone, can improve theflotation yield; Sec octyl alcohol, A foaming agent, B foaming agent modifiedby emulsification and chemical modification combined, the flotation yield ishigher than emulsification or chemical modification act individually.