Study On Coal Quality In Huanghaojie District,Shanxi Province

Huanghaojie well field,located in the northeastern of the Jingbian County,Shanxi Province,which administrative divisions are subordinate to Huanghaojie town,jingbian county,Zhaoshipan town and Tawan town.However,sufficient understanding and study of the quality characteristics and variation law of the coal seam,in particular,the systematic studying,are lacking,to the disadvantage of exploit and utilize coal resource in right amount.Huanghaojie well field is located at the middle part of the Ordos Block,which was mainly covered by the Quaternary stratigraphic succession includes the Middle Pleistocene Lishi Formation,the Upper Pleistocene Malan and Salawusu formations,and the Holocene Modern riverbed alluvial and diluvial.The strata uncovered by drilling holes under construction was Ciyaobu Formation,Fuxian Formation,Yanan Formation,Zhiluo formation,Anding Formation and Luohe Foramtion.To investigates the Coal-bearing rock and coal seam characteristics,we performed field geological surveys,drilling wells and samples.The following findings were obtained in this work.The coal-bearing strata is the Middle Jurassic Yanan Formation.There are 5 ~ 7 coal seams,and four of contrast,numbered as 3,4,5,8 from up to down.The No.3 coal seam is the whole minable coal seam,and the No.4 coal seam is the localone.According our drilling data and sample test,the accumulated thickness of the whole coal seam of the Yanan Formation is about 2.90 ~ 5.70 m,with an average of4.48 m.The accumulated thickness of the coal seam increases gradually from east to west in the study area,and the plane change is obviously.The coal content was 1.17 ~2.57%,with an average of 1.98%.The cumulative thickness of the recoverable coal seam is 1.75 ~ 4.05 m,with an average of 2.56 m,and the coal coefficient is 0.83 ~1.63%,with an average of 1.13%.The coal seam is distributed throughout the region,with a maximum thickness of 3.10 m,a minimum thickness of 1.75 m,and an average thickness of 2.42 m.The maximum thickness of minable coal seam is 2.95 m,the minimum is 1.75 m,the average thickness is 2.40 m,the standard deviation is 0.28,and the coefficient of variation is 11.0%.The coal seam is thicker in the middle and south of the study area,and gradually thins to the north and east.According to relevant norms and standards,no.3 coal seam meets the medium-thick coal seam standard.The correlation of coal seam is sufficient and with a reliability high degree: the correlation of No.3 and No.4 coal seam is reliable,while No.5 and No.8 coal seam are relatively reliable.The coal formed in this area have the ground-low ash,high volatility,medium-high sulfur,and high-extra high calorific value coal features there.The No.3 coal seam is mainly long-flame coal,and the No.4 coal seam is all long-flame coal.