Method for mining coal bed gas by hydraulic washout of butted well in manner of pressure relief

A technology for docking wells and coalbed methane, applied in the direction of mining fluids, drilling equipment and methods, drilling equipment, etc., can solve problems such as difficulty in maintaining pressure relief space, easy collapse, blockage, etc., and achieve the effect of increasing pressure relief space

Inactive Publication Date: 2012-06-27
ZHENGZHOU UNIV
View PDF5 Cites 38 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there are a considerable number of soft, low-permeability, and high-gas coal seams in China. Conventional horizontal well drilling technology is difficult to achieve. It is

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for mining coal bed gas by hydraulic washout of butted well in manner of pressure relief
  • Method for mining coal bed gas by hydraulic washout of butted well in manner of pressure relief
  • Method for mining coal bed gas by hydraulic washout of butted well in manner of pressure relief

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0024] The present invention will be further described below in conjunction with an embodiment (accompanying drawing):

[0025] Such as figure 1 , figure 2 , image 3 , Figure 4 As shown, the specific implementation steps of the method for exploiting coalbed methane by hydraulic scouring and pressure relief of butt-connected wells of the present invention are as follows:

[0026] (1) Drilling and mining vertical well 3 is set at predetermined position, and this well is drilled by ground 1, and after passing through target coal seam 2, continues to drill into pocket 4 of a certain distance, promptly forms the pit of gathering coal water.

[0027] (2) Run a special casing in the second section of the corresponding target coal seam, usually a fiberglass casing. After cementing, cut off the fiberglass casing to expose the coal seam and ream the hole to form a cave 5.

[0028] (3) Coal-water lifting equipment 6 is set in the aforementioned drainage vertical well, and gas, coa...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for mining coal bed gas by hydraulic washout of a butted well in the manner of pressure relief, which comprises the following steps: firstly, drilling a drainage vertical well (3); digging the section of a target coal bed (2); forming a pocket (4) after passing through the coal bed; drilling a vertical well section (9) and a deviating section (10) of a horizontal directional well (8) and laying a casing pipe for well cementation; then, drilling a channel of a horizontal section (11) by using a conventional measure; butting the channel of the horizontal section (11) with the drainage vertical well (3) for barefoot well completion; continuously injecting water into the horizontal directional well (8) to wash the coal bed of the horizontal section (11); gathering coal water into the pocket (4); discharging the coal water through lifting equipment (6); when pulverized coal does not exist in the pocket (4), laying a water spray hose (12); by means of the action of high-pressure water jet, ejecting out a plurality of branch boreholes (13) at the horizontal section (11); continuously injecting the water to wash until the pulverized coal does not exist in the pocket (4) any longer; closing the horizontal directional well (8); and entering a conventional water draining and gas mining stage. The invention provides a new resolution for ground gas mining from soft low-permeability coal beds.

Description

technical field [0001] The invention relates to the technical field of coalbed methane mining, and may also relate to the technical field of surface coal and gas co-mining, in particular to a method for mining coalbed methane by hydraulic scouring and pressure relief in butt joint wells suitable for soft, low-permeability, and high-gas coal seams. Background technique [0002] Drilling technologies for surface mining of coalbed methane are mainly vertical wells and horizontal wells. Vertical wells are drilled from the ground to pass through the coal seam, and cracks are created in the coal seam by means of fracturing, thereby releasing and extracting coalbed methane. The construction of vertical wells is simple and the cost is low, but this technology is mainly suitable for hard and thick coal seams with flat terrain and good permeability, and is not suitable for soft and low-permeability coal seams. A horizontal well refers to a well whose inclination angle reaches or is c...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): E21B43/00E21B7/18E21B43/30E21B7/04E21B7/20E21B7/28
Inventor 冯立杰余华杰王金凤钟华珂翟雪琪李朝辉马鸿廉李耀辉冯奕程盛旭阳何传星
Owner ZHENGZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap