Underground in-situ fluidized mining method for deep coal resources

Abstract

The invention provides a deep coal resource underground in-situ fluidization mining method which comprises the following steps: determining a coal seam needing fluidization mining, and arranging a U-shaped well group in the coal seam; secondary transformation is conducted on the horizontal well, a plurality of horizontal branch wells are drilled along different positions of the horizontal well, and a fishbone well is built; fracturing a coal seam around the fishbone well in a manner of injecting high-pressure fluid into the fishbone well; air is injected into the fishbone well through the horizontal well; a methane-air mixture in the complex crack is ignited or detonated in an electric shock ignition mode, and a potassium permanganate solution in the complex crack is promoted to release oxygen by using a high-temperature environment generated by combustion and explosion of methane and air; in-situ conversion of underground coal is continuously carried out, and along with continuous in-situ fluidized mining, coal around the fishbone well is continuously mined in a fluidized form; and meanwhile, the combustible gas generated by conversion is separated and stored on the ground. According to the method, the working face of coal seam in-situ fluidization mining can be effectively enlarged, and the fluidization mining and conversion efficiency can be remarkably improved.

Description

technical field [0001] The invention belongs to the technical field of deep coal mining, and in particular relates to an underground in-situ fluidized mining method for deep coal resources. Background technique [0002] At present, coal is still the main energy source in my country, and its resources account for more than 90% of the basic reserves of fossil energy resources. With the decreasing of shallow resources, coal mining gradually turns to deep, and the mining depth continues to increase at a rate of 8-12m / year. Deep coal mining will face complex geological environments such as high rock formation pressure, large water inflow and high ground temperature. Sudden engineering disasters and frequent accidents will seriously affect the safety of underground personnel and mining equipment. Under the current technical system, the limit depth of coal mining is about 1500m. When this depth is exceeded, the existing technical level will not be able to meet the requirements of ...

AI Technical Summary

Problems solved by technology

[0003] Aiming at the problems existing in the existing technology of deep coal mining, the present invention provides an underground in-situ fluidized mining method for deep coal resources, which can not only solve the problems of frequent safety accidents, serious environmental pollution and Low development efficiency and other problems can also realize in-situ fluidized mining of coal, and can effectively increase the working face of in-situ fluidized mining of coal seams, can significantly improve the efficiency of fluidized mining and conversion, and at the same time, help promote The in-situ fluidization transformation of coal is carried out to the depth of the coal seam, which can provide strong technical support for the in-situ fluidization mining of deep coal resources

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