Water jet dense comb-shaped hole drilling type to-be-tunneled roadway coal seam gas outburst elimination backing pump treatment method

Abstract

The invention discloses a water jet dense comb-shaped hole drilling type to-be-tunneled roadway coal seam gas outburst elimination backing pump treatment method which comprises the following steps: I,constructing orientated long drilling holes; II, constructing water jet dense comb-shaped holes; III, sealing holes, and extracting and exploring gases. By adopting the method, very small radius water jet dense comb-shaped branched holes are constructed in a bottom plate of a to-be-tunneled roadway in an underground coal mine, hole drilling depths of single branch holes are reduced, the number ofbranch holes is greatly increased, the coal layer permeation improvement and gas extracting and discharge effects of the orientated long drilling holes are improved, the purpose of to-be-tunneled roadway coal seam gas backing pump outburst elimination can be achieved, and safe tunneling of a coal seam roadway is ensured.

Description

technical field [0001] The invention relates to the technical field of coal seam gas control, in particular to a water jet intensive comb-shaped drilling type coal seam gas outburst pre-extraction control method for roadway to be excavated. Background technique [0002] With the increase of coal mining depth in my country, the in-situ stress, gas gradient, gas content and gas emission volume continue to increase, high-gas mines and outburst mines are also increasing, and the frequency and intensity of coal and gas outbursts and gas overruns are also increasing. Therefore, it is necessary to take measures to prevent coal and gas outburst and gas overrun in underground coal roadway excavation. The pre-extraction of gas by drilling is an effective means to control gas outburst and overrun. At present, the main method of gas control in the coal roadway to be excavated is to first construct the gas drainage rock roadway in the coal roadway floor rock layer, and then construct the ...

AI Technical Summary

Problems solved by technology

The effect of gas pre-extraction by using the drilling roadway to drill through the layers is the best, but the construction period is long and the cost is high; the economy and period of gas pre-extraction by using the directional long drilling holes along the coal seam are good, but the main problems The problem is that the coal seams of high-gas or outburst mines are relatively broken, and the directional long boreholes in construction are prone to hole collapse or even drill stuck accidents under high ground stress and high gas pressure, which greatly affects the effect of drainage and outburst prevention; Although the pre-pumping of directional comb-shaped drilling in the floor can avoid accidents in the main hole to a certain extent, there are problems that the number of branch drilling is limited, and the drilling rate of the whole hole coal seam is low, and the drainage effect is difficult to guarantee.

Images