Reasonable Hole Distribution Parameters of High-location Directional Long Drilling Replacing Roadway
To solve the problem of gas in the upper corner of the working face caused by low content and high intensity mining in No.2 coal seam of Liujialiang Mine,alleviate the situation of mining replacement caused by rock roadway driving.A gas control technology was proposed to replace the low rock extraction roadway of the working face with a major diameter high-location directional long drilling.Combining with the physical and mechanical parameters of the roof of No.2 coal seam,through theoretical analysis and numerical simulation,the gas flow channel and its occurrence rule were analyzed and studied from different professional perspectives such as the development of fractured zone in working face and the flow field distribution in goaf in working face,which provided theoretical support for the selection of reasonable layout of directional high level boreholes.According to the gas extraction effect of the No.1 drilling field,the coal and rock occurrence data of the working face were modified,the extraction design of drill yard No.2 was optimized and the drilling layout parameters was adjusted.Taking the pure amount of gas extraction in the working face and the concentration of gas in the upper corner as indicators,the effect of gas treatment under different conditions was compared.The practice proved that the long borehole towards the high position could replace the low rock extraction roadway and be used for the gas treatment in the upper corner of the top coal caving work with low content occurrence and high intensity mining.The treatment effect was remarkable,and the concentration of gas in the upper corner was maintained below 0.6％.
high-location directional long drillingreplace roadway with boreholeupper cornerhorizontal hole rangedrilling pa-rameters
万方数据
维普
