Study On Preparation Of Ultra-pure Coking Coal

Coal is important material basis for social development and plays an important role in the development of human society.China is the world's largest coal producer and consumer country,and it is abundant in all types of coal from lignite to anthracite.However,the power coal(non-coking coal)is rich in resources,and high quality coking coal resources are scarce.Compared with the world average level,the quality of coke in our country is very poor,especially the ash is high,and the coke ash on the harm of smelting cannot be underestimated,coke ash for every 1% increase in blast furnace to consume 4% flux,slag increased by 3%,so the low quality of coke due to high ash coking coal,coking high cost,seriously affected product quality and technical and economic benefits of the steel industry,it has become the key to improve the quality of coking coal.In addition,ultra-low ash coal can be used to produce high value-added products such as coal-based carbon materials,coal-based fuels,which have higher demand on the raw coal ash,and in addition to individual coal,the vast majority coal prepare to make the ultra-pure coal must go through the crushing and dissolution.Based on this,the research on the preparation of the ultra-pure coal is put forward.In this paper,the preparation of ultra-pure coking coal began to explore from the fine particles of primary slime,by analyzing the existence of coal ash in the form of ash and its dissociation,after fine grinding the fine particle carry out "granulation" flotation.The effects of different molecular weight PAM and its dosage,amount of dispersant and amount of flotation agent on the flocculation and flotation process were analyzed.After the fine grinding-selective flocculation process,the ash was 9.12% of the original coal slag sorted to the ash is 3.27%,the yield of 50.08%,due to the role of high ash fine mud interference,The ash of fine particles of primary coal can not be further reduced.The paper further explored the ultra-pure preparation process by using the fine coal which has been re-elected to remove the high-ash fine mud component,and making the fine grinding-selective flocculation flotation process with refined coal which ash is 3.52%,control the appropriate grinding fineness,strengthen the hydrophobic action of coal particles by using sub-dosing to strengthen the flotation process,then explore the electric stirrer speed and time control,flocculation and stirring speed and time control,and the amount of flocculant agent.The results show that when the coal sample is pulsed to d80 is 19.03?m,the diesel oil is stirred and the polyacrylamide is added as the flocculant,the ultrafine coal with the ash content of 1.54% and the yield of 62.85% is obtained.In this paper,an exploratory test was carried out on the cyclone static microbubble flotation column,the ash was 1.38% and the average yield was 65.13%.In the last,the flocculation of PEO flocculated clay minerals and PAM on coal particles were compared,the results show that the simple clay flocculation can not improve the sorting effect of fine granular coal in the slurry.