Research On The Preparation Of Gemini Microemulsion Collector And Coal Flotation Performance

In China's primary energy consumption,fossil energy,especially coal,dominates.Low-rank coal accounts for more than 50%of China's current coal reserves.Efficient development and utilization of low-rank coal will greatly ease the pressure on China's energy supply.Due to the low degree of metamorphism,low-rank coal will produce a large amount of coal slurry during mining and transportation.At present,the main method of coal slurry recycling is flotation,but the surface of low-rank coal slurry is high in oxygen and poor in hydrophobicity.The flotation effect of traditional collectors is not ideal.Therefore,it is of great significance to develop a suitable low-rank coal slurry collector to improve the flotation effect of low-rank coal slime.In this study,Gemini microemulsion collector was prepared with Gemini surfactant,and flotation test was carried out on low-rank coal slurry of a coal preparation plant in Shenhua Shendong mining area.The Gemini microemulsion collector was found for low rank coal.The flotation performance of the mud illustrates the mechanism of action of the Gemini microemulsion collector.The main contents and conclusions of the study are as follows:(1)Using Gemini surfactant(GEM)as the main surfactant and 0#diesel as the oil phase,the basic formula of the microemulsion collector is determined by the water-in-oil dilution method,the ternary phase diagram method and the conductivity method;The response surface method was used to optimize the formulation.The best formula obtained was:GEM:n-octanol:0#diesel:water=30.97%:30.97%:32.37%:5.69%,average particle size of microemulsion collector At 42.12nm,it meets the microemulsion requirements.(2)The results of low-rank coal slurry flotation show that under the condition of 3kg/t of Gemini microemulsion collector and no foaming agent,the flotation index is 64.38%of clean coal yield and 10.72%of clean coal ash.The recoverable rate of combustibles is 69.60%.When 0#diesel is used as the collector,the amount of diesel is 8kg/t,and the amount of foaming agent is 0.8kg/t.The flotation index at this time is 55.64%of clean coal,10.66%of clean coal,and the yield of combustibles.60.31%.Compared with traditional flotation reagents,the combustible recovery rate of Gemini microemulsion collector increased by about 10%,while the amount of combustibles decreased by 62.50%,while reducing the addition of foaming agent.The link simplifies the flotation reagent system.The flotation kinetics of the two collectors also showed that they all follow the classical first-order kinetic model,but the flotation rate of the microemulsion collector is faster than 0#diesel.(3)XPS study showed that the carbon-oxygen ratio increased on the surface of the slime after microemulsion treatment,indicating that the Gemini microemulsion collector was effectively adsorbed on the surface of the low-order coal slime,which was effective for oxygen-containing functional groups.Coverage,which improves the hydrophobicity of low-rank coal slime,thereby improving the flotation performance of low-rank coal slime.