Bedding drill hole air-leakage-preventing gas extraction method

Abstract

Disclosed is a bedding drill hole air-leakage-preventing gas extraction method. The bedding drill hole air-leakage-preventing gas extraction method comprises two stages of building of a main gas extraction system and building of an auxiliary gas extraction system, specifically, firstly, a main gas extraction pipeline is laid inside a roadway, bedding extraction drill holes are constructed, the bedding extraction drill holes are sealed, and drill hole gas extraction pipes are connected to the main gas extraction pipeline to conduct gas extraction; and after the drill holes in the roadway are all sealed to conduct extraction, an airtight wall is constructed at an opening of the roadway where the drill holes are constructed, an auxiliary gas extraction pipeline is laid, and an auxiliary extraction pipe is connected with an auxiliary gas pump extraction pipeline to conduct auxiliary extraction. According to the bedding drill hole air-leakage-preventing gas extraction method, under the effect of the auxiliary extraction negative pressure, the atmospheric pressure in the roadway can be gradually reduced and finally reaches or approximates to the extraction negative pressure in the drillholes, and the problem that air leakage is serious in the bedding drill hole extraction process can be effectively solved; the technology is simple, implementation is easy, and a large amount of laborcost can be saved; and the bedding drill hole air-leakage-preventing gas extraction method is suitable for bedding drill hole gas extraction of various coal mines, and particularly suitable for mineswhere air leakage is serious in the extraction process.

Description

technical field [0001] The invention relates to a method for gas drainage in areas with serious air leakage during the bedding drilling drainage process, and belongs to the field of coal mine gas bedding drilling drainage. Background technique [0002] When using boreholes for coal seam gas extraction, the gas concentration (volume percentage) extracted from well-sealed and airtight boreholes should be close to 100% in theory, but in the actual extraction process, due to the leakage of a large amount of air, As a result, the concentration of gas drainage in most mines in my country has been below 30% for a long time. [0003] Two conditions must be met for the existence of air leakage in the gas drainage process. One is that there must be an air leakage channel, and the other is that there must be a pressure difference between the two ends of the air leakage channel. The existing related technologies all focus on plugging the air leakage channel, but on the one hand, the dev...

AI Technical Summary

Problems solved by technology

The existing related technologies are all focused on sealing the air leakage channel, but the development of the air leakage channel is relatively complicated on the one hand, and on the other hand, there may be changes with the extraction time

Therefore, in the actual extraction process, although the hole sealing process of sealing the air leakage channel has been carried out, there is still a certain degree of air leakage. Failure phenomenon, and high cost

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