Decomposition Characteristics And Enhanced Gravity Enrichment Of Shendong Long Flame Coal Macerals

The low-rank bituminous coal of Shigetai Coal Mine under the Shenhua Group has the characteristics of low ash,low sulfur,high volatility,high hydrogen content and good chemical reaction.Low-order coal has good reactivity,high oil yield and high conversion rate.It has become one of the main coal types in China to study coal-to-liquid technology.The vitrinite and chitin groups are the active components of coal-to-oil,and the inert group is the inert component of coal-to-oil.The higher the active component,the higher the oil yield of coal-based oil.high.Therefore,it is of great significance to explore the difference in properties between the liquefied active component and the inert component in the micro-components of coal rock,and to use the difference to complete the dissociation and enrichment between the micro-components of coal rock.Based on the differences in the properties of the coal and rock micro-components,this paper explores the fragmentation and dissociation behavior of each component during the grinding process by setting different grinding conditions,and finds the best dissociation of the coal-rock micro-components.After the conditions,the products of Shenhua low-order bituminous coal dissociated were sorted and enriched by using a Falcon sorting machine.This thesis takes Shenhua low-rank bituminous coal as the research object,its ash is 8.77%,sulfur is 0.33%,volatilization is 35.62%,the composition of coal maceral is vitrinite group content 48.42%,and inetinite group content is 46.32%.The chitin group content was 1.58%and the mineral content was 3.68%.The vitrinite group and the inertinite group are the main components of the coal rock micro-component,and the vitrinite content is slightly higher than that of the inert group.The raw coal was subjected to rough selection by manual selection,screening and heavy liquid centrifugal enrichment.Through the rod grinding and ball milling grinding experiments,and setting IIdifferent grinding time and grinding feed amount,the disintegration behavior of the vitrinite group and the inertinite group of coal macerals during the grinding process was explored.With the increase of grinding time,the vitrinite component is gradually dissociated,but the grinding time is too long,which will lead to the mismatch of the vitrinite component and the inert component.10min is the best grinding time.With the increase of feeding amount,the crushing efficiency is reduced,but the selective crushing effect is manifested,and the inertinite group is disintegrated to the small particle size in preference to the vitrinite group.The crushing method of the rod mill leads to the selective crushing effect on the micro-components of the coal macerals.Therefore,the rod grinding method is selected to grind the coal sample and then the coal rock micro-components are sorted and enriched.The product after the rod mill test was subjected to a floating-sink test,and the product of-1.35 g.cm^-3 density grade was used as the product of the vitrinite group,and the vitrinite group of 1.35 g.cm^-3 density was obtained at a rod grinding time of 10 min and a feed amount of 100g.The content reached 81.34%.The optimal operating parameters for the centrifugal gravity sorting in Falcon are the rotational frequency30Hz,the recoil water pressure 0.03MPa,and the feed rate 15ml/s.Under this test condition,the vitrinite content of the overflow product is 67.25%.The set rate reached 72.48%.