Application of gas drainage technology with high level boreholes in Zhuzhuang Mine

In order to reduce the mine gas disaster and ensure effective practices of the gas drainage technology with the high level bore- holes,with the analysis and research on three zones of movement of overlying strata of No.4 seam in Zhuzhuang Mine,the paper set the height of the fissure zone of the high level borehole in the roof strike of No.4 seam and provided the rational design parameters of the lay- out for the borehole drilling site and borehole drilling.Based on the parameters,the gas drainage technology with high level boreholes was applied to No.Ⅲ4414 fully mechanized coal mining face in Zhuzhuang Mine.In comparison with the adjacent coal mining faces,the gas drainage rate with the high level boreholes of the No.m 4414 coal mining face was increased about 2 times.Due to the gas drainage rate of the up corners of the coal mining face and the gas emission quantity from the coal mining face was reduced,there was no gas content o- ver the limits in the coal mining face during the face mining period and the safety production condition of the face was improved.