顺层瓦斯预抽钻孔布置参数及抽采效果分析

Analysis of layout parameters and extraction effect of bedding gas pre-extraction boreholes

为了对顺层瓦斯预抽钻孔布置参数及抽采效果进行分析,采用理论分析和现场测试,分析了顺层钻孔布置间距、钻孔极限抽采时间,研究了顺层钻孔预抽瓦斯效果检验和瓦斯效果。研究表明,多钻孔抽采瓦斯时,钻孔间距可大于2倍的有效抽采半径,得出了布孔间距和单钻孔抽采半径的关系计算式,极限抽采时间约为95 d;在工作面回采期间,回风巷风排瓦斯量和顺层钻孔抽采瓦斯量呈相反的趋势;经过钻孔瓦斯预抽后,工作面预抽率达到了40%,达到了工作面消突的目的。

In order to analyze the layout parameters and the extraction effect of bedding gas pre-extraction boreholes,the theoretical analysis and field test are used to analyze the spacing of the pre-extraction holes in the bedding,the limit extraction time of the holes,and the test and gas effect of the pre-extraction holes in the bedding gas are studied.The research showed that the distance between holes can be more than 2 times of the effective extraction radius,and the relationship between the distance between holes and the single hole extraction radius was obtained.The ultimate extraction time was about 95 days.During the mining period of the working face,the amount of gas extraction gas in the return airway and the amount of drilling gas in the seam have the opposite trend.After the drilling gas pre extraction,the pre-extraction rate of the working face reached 40%.It has achieved the purpose of working face outburst elimination.