Process for pumping and exploiting coal bed gas by together using ground well drilling and underground hole drilling

Abstract

The invention relates to a coal bed gas exploiting technique, in particular to a process for pumping and exploiting coal bed gas by together using ground well drilling and underground hole drilling, solving the problem of low efficiency of the traditional method for pumping and exploiting the coal bed gas. The process comprises the following steps of: (1) carrying out well drilling on the ground; (2) carrying out long hole drilling in underground coal beds; (3) making drilled holes and ground drilled wells crosslink and communicate in the appointed points by utilizing an orientation technique of a long hole drilling machine; (4) effectively closing the underground long drilled holes; (5) fracturing the ground drilled wells and the underground long drilled holes by utilizing fracturing equipment on the ground; (6) after fracturing, closing the ground drilled wells; and (7) opening the closed ends of the underground long drilled holes and then installing relevant pumping and discharging pipelines connected with underground pumping and discharging systems. The process improves the pumping and exploiting speed and efficiency of the coal bed gas, shortens the construction period of coal bed gas pumping and exploiting engineering and saves the construction investment of the coal bed gas pumping and exploiting engineering.

Description

technical field

[0001] The invention relates to a coalbed methane mining technology, in particular to a coalbed methane extraction technology combined with surface drilling and downhole drilling. Background technique

[0002] Underground drilling drainage is one of the main measures to control coal mine gas and eliminate coal and gas outburst. Through drainage, the gas content in coal seams can be reduced, the amount of gas gushing out during mine mining can be reduced, and the risk of coal and gas outburst can be reduced. At present, there are two ways to deal with coalbed methane. One is to drill wells on the ground in coalfield areas with high concentration of gas, and then use water injection and fracturing to increase the cracks in the coal seam and discharge the gas, and then export the gas through well pipes; However, in many cases, only surface drilling is used to fracturing a limited range, the drilling volume is low, and the extraction time is long. Another way is...

Examples

Embodiment Construction

[0012] Such as figure 1 Illustrated, a kind of ground drilling and downhole drilling combined extraction technique for coalbed methane comprises the following steps, (1) constructing ground drilling 1 on the ground, with a construction point every 250 meters in the straight line direction; Construction of long borehole 3 in 10, constructing a borehole with a horizontal direction of 30-50 meters, (3) utilizing the directional technology of the long borehole drilling machine to make the long borehole 3 and the ground well 1 cross-linked at the designated intersection point 5, (4) Effectively seal the long borehole 3 in the well, and the length of the closed area 4 is 20 meters to 30 meters. (5) Use fracturing equipment on the ground to perform fracturing on the ground well 1 and the long borehole 3 in the well to generate the affected area of ​​the ground well fracturing 2 and the long borehole fracturing affected area 7, the fracturing pressure is 6-10MPA, (6) after the fractur...

technical field

[0001] The invention relates to a coalbed methane mining technology, in particular to a coalbed methane extraction technology combined with surface drilling and downhole drilling. Background technique

[0002] Underground drilling drainage is one of the main measures to control coal mine gas and eliminate coal and gas outburst. Through drainage, the gas content in coal seams can be reduced, the amount of gas gushing out during mine mining can be reduced, and the risk of coal and gas outburst can be reduced. At present, there are two ways to deal with coalbed methane. One is to drill wells on the ground in coalfield areas with high concentration of gas, and then use water injection and fracturing to increase the cracks in the coal seam and discharge the gas, and then export the gas through well pipes; However, in many cases, only surface drilling is used to fracturing a limited range, the drilling volume is low, and the extraction time is long. Another way is...

Examples

Embodiment Construction

[0012] Such as figure 1 Illustrated, a kind of ground drilling and downhole drilling combined extraction technique for coalbed methane comprises the following steps, (1) constructing ground drilling 1 on the ground, with a construction point every 250 meters in the straight line direction; Construction of long borehole 3 in 10, constructing a borehole with a horizontal direction of 30-50 meters, (3) utilizing the directional technology of the long borehole drilling machine to make the long borehole 3 and the ground well 1 cross-linked at the designated intersection point 5, (4) Effectively seal the long borehole 3 in the well, and the length of the closed area 4 is 20 meters to 30 meters. (5) Use fracturing equipment on the ground to perform fracturing on the ground well 1 and the long borehole 3 in the well to generate the affected area of ​​the ground well fracturing 2 and the long borehole fracturing affected area 7, the fracturing pressure is 6-10MPA, (6) after the fractur...

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