Method for achieving ground coal bed gas production through cluster well and horizontal well under complex terrain condition

Abstract

The invention discloses a method for achieving ground coal bed gas production through a cluster well and a horizontal well under a complex terrain condition. The method for achieving ground coal bed gas production through the cluster well and the horizontal well under the complex terrain condition comprises the following steps that a, the cluster well is constructed and is fixed; b, the horizontal well is constructed and fixed; c, gun perforation and fracturing construction are conducted on a target coal bed section of the cluster well in sequence, and a pressure meter is installed on the mouth of the cluster well; d, segmented gun perforation and fracturing construction are conducted on the horizontal well in sequence, and the change of the reading of the pressure meter on the mouth of the cluster well is monitored during fracturing; e, overflowing is slowly conducted on the cluster well and the horizontal well in sequence till the surface casing pressure is zero; f, water drainage and gas production are conducted after a drainage and production device is installed on the cluster well, and only a gas production well mouth is installed on the horizontal well. According to the method for achieving ground coal bed gas production through the cluster well and the horizontal well under the complex terrain condition, overall depressurization of a coal reservoir within the control range of the cluster well and the horizontal well can be achieved, the ground production range of coal bed gas in areas with burial depths of target coal beds changing greatly is remarkably widened, a ground coal bed gas production project is simplified, and equipment investment is reduced.

Description

technical field

[0001] The invention relates to the technical field of surface mining of coalbed methane, in particular to a method for surface mining of coalbed methane combined with cluster wells and horizontal wells in areas with complex topographical conditions and large coal seam dip angles. Background technique

[0002] my country is rich in coalbed methane resources, and the geological resources of shallow coalbed methane with a buried depth of 2000m are predicted to reach 36.8×10 12 m 3 , equivalent to conventional natural gas resources. Large-scale development of coalbed methane can alleviate the shortage of conventional oil and gas energy in my country, reduce the probability of coal mine gas accidents, reduce greenhouse gas emissions in coal mine production, and produce significant economic, environmental, safety and social benefits.

[0003] Southwest my country, represented by eastern Yunnan and western Guizhou, is rich in coalbed methane resources and has gre...

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