Research On Technology Of Increasing The Lump Coal Rate Of Fully-mechanized Working Face In Yifeng Coal Mine

With the wide application of high power shearer,the lump coal rate of mining face is reduced greatly due to comprehensive mechanized mining.In consideration of the unique economic and environmental value of lump coal,it is an urgent technical problem to be solved that how to improve the lump coal rate of fully-mechanized mining face.Taking Yifeng Coal Mine of Fugu in northern Shaanxi province as the research object,through the comprehensive methods of theoretical analysis,technical scheme design,equipment development and field engineering practice,the key technical measures to improve the lump coal rate of fully-mechanized mining face in Yifeng Coal Mine are finally determined.(1)Carrying out field investigation,the geology and mining conditions of Yifeng Coal Mine as well as the main parameters and mining technology of the shearer have been analyzed.Then the research for improving the lump coal rate of the fully-mechanized mining face in Yifeng Coal Mine is made from two aspects:coal shearer parameter improvement and coal seam weakening.(2)Based on the study of parameter improvement of shearer,the paper designs the technicall scheme for improving shearer parameters of Yifeng Coal Mine.Moreover,the shearer drum with high lump coal rate of Yifeng Coal Mine has been developed.(3)Based on the study of coal loose blasting theory,the blasting weakening technical scheme of the fully-mechanized mining face in Yifeng Coal Mine is designed.The technical scheme is divided into two directions:the coal wall presplit blasting and the advanced weakening of the mining face.(4)According to the design of the technical scheme,combined with the actual situation of the coal mine,the test mining face successively adopts the technology of coal wall presplit blasting in the mining face,the technology of shearer drum with high lump coal rate,the measure for the combination of block rate drum technology and coal wall blasting weakening technology in working face,and the measure of combining block rate roller technology with blasting weakening technology in advanced working face to carry out the industrial test.(5)T he test results show that:the lump coal rate of underground mining face increases 4.34%by adopting the shearer drum with high lump coal rate;the lump coal rate of underground mining face increases 14.22%by coal wall presplit blasting in the mining face;the lump coal rate of underground mining face increases 11.72%by the technical measures for weakening advanced working face by blasting;the lump coal rate of underground mining face increases 18.56%by the combination of the shearer drum with high lump coal rate and wall presplit blasting in the mining face;the lump coal rate of underground mining face increases 16.06%by the combination of the shearer drum with high lump coal rate and weakening advanced working face by blasting.The measure for the combination of the shearer drum with high lump coal rate and the technology of presplit blasting in the mining face is the effective way to increase the lump coal rate of fully-mechanized mining face.The research provides an effective way to improve the economic benefit and to keep the sustainable development of the fully-mechanized coal mine.