Porous collaborative fracturing and extracting integrated gas extraction method

Abstract

Disclosed is a porous collaborative fracturing and extracting integrated gas extraction method applicable to gas extraction performed in high-gas low-permeability coal beds. The method includes: firstly, evenly and alternatively constructing a plurality of fracturing pores and gas extraction pores in a lane towards the coal bed according to row-column intervals; secondly, sealing all the fracturing pores according to the requirement of the minimum bearable pressure of 20MPa, and sealing all the gas extraction pores according to a conventional method; thirdly, connecting the gas extraction pores adjacent to the fracturing pores with underground gas extraction pipelines; and fourthly, adopting gas-liquid two-phase flow fracturing media to fracture each fracturing pore one by one, and performing gas extraction on all the gas extraction pores adjacent to the fracturing pore while fracturing so as to achieve porous collaborative fracturing and extracting integrated gas extraction. The method is low in construction cost and good in effect, and has high practicability.

Description

technical field [0001] The invention relates to a multi-hole cooperative pressure-drainage integrated gas drainage method, which belongs to the technical field of gas control in underground areas of coal mines, and is especially suitable for gas drainage operations in high-gas and low-permeability coal seams. Background technique [0002] Gas explosions and coal and gas outburst accidents are the main disasters in coal mines. The national coal mine gas control policy determines that high gas mines must be pumped before mining, and gas drainage is a permanent measure. Coal seams in my country generally have characteristics such as low gas permeability and low adsorption gas saturation, and most coal seam gas drainage effects are poor. In order to achieve drainage standards, it is necessary to implement anti-permeability measures for coal seams. In recent years, various water conservancy measures have been applied in the process of coal mine gas control, which have played a ce...

AI Technical Summary

Problems solved by technology

Coal seams in my country generally have characteristics such as low gas permeability and low adsorption gas saturation, and most coal seam gas drainage effects are poor. In order to achieve drainage standards, it is necessary to implement anti-permeability measures for coal seams

In recent years, various water conservancy measures have been applied in the process of coal mine gas control, which have played a certain role, but the hydraulic measures are single, not closely combined with gas drainage, and there are phenomena such as unreasonable layout of gas drainage boreholes

Publication Nos. CNIO1614134A and CNIO1614135A disclose the three-in-one pressure relief and outburst prevention method of drilling, blasting, and pumping and the three-in-one gas drainage method of drilling, blasting, and pumping. The sequence of blasting first and then drainage does not form the synergy between blasting holes and gas drainage holes, and the blasting method is more risky, and it is easy to cause gas disasters such as gas explosions

Moreover, the existing various pressure relief and antireflection measures have complex construction techniques and high costs.

There is blindness in coal seam enhancement and gas drainage, and measures cannot be formulated and implemented scientifically, resulting in insufficient coal seam pressure relief, and gas drainage cannot achieve the desired effect, which wastes manpower and material resources, and fails to achieve the desired effect

In order to solve the technical problems of the blindness of coal seam permeability enhancement and poor gas drainage effect in the existing measures, it is urgent to find a new coal seam pressure relief and permeability enhancement gas drainage method

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