Outburst prevention method in rock cross-cut coal uncovering and gas outburst coal seam double-curtain grouting

Abstract

An outburst prevention method in rock cross-cut coal uncovering and gas outburst coal seam double-curtain grouting is suitable for being used in a mining work face. When the minimum excavated normal distance from a rock cross-cut coal uncovering work face to a coal seam is no less than 7m, two circles of cross-measure grouting holes inclining to the outer side of a cross cut are drilled in the front side of the rock cross-cut coal uncovering work face in the coal seam direction, cement mortar are injected into the cross-measure grouting holes, two gas leakage prevention curtains are manufactured in coal around the rock cross-cut coal uncovering work face to prevent gas around the cross cut to move to the direction of the cross cut, and then the cross-measure grouting holes are used for pre-vacuum of gas in the coal seam in front of the cross cut to reduce pressure and content of the gas. The method is simple and easy to achieve, short in working hour, safe, efficient and low in cost.

Description

technical field [0001] The invention relates to an outburst prevention method, and is especially suitable for a double-curtain grouting anti-outburst method used in a coal mining face for uncovering coal at a stone gate and a gas outburst coal seam. Background technique [0002] Gas is one of the main factors that seriously threaten the safe production of coal mines. More than 70% of coal accidents in our country are gas accidents. At present, my country's mine mining is characterized by large mining depth, low coal seam permeability, high gas pressure, high gas content, and difficulty in pre-pumping coal seam gas. In addition, the geological conditions of the mining coal seam are complex and affected by mining. Under certain conditions, there will be A dynamic phenomenon in which coal and gas outbursts are produced. [0003] In coal and gas outburst accidents, it is more likely to occur when exposing dangerous coal seams with coal and gas outburst. Due to the unstable occu...

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Problems solved by technology

However, the gas flow in the coal seam conforms to the spherical flow, and the gas flow field belongs to the spherical flow field. Under the action of the gas pressure gradient, the gas will be continuously supplied to the direction of Shimen, and it is difficult to effectively reduce the gas content and pressure of the coal seam around Shimen. Coal and gas Outstanding dangers still exist

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