A Coal Seam Water Injection Method Enhanced by Pressure Dynamic-Electric Coupling

A coal seam water injection and action technology, applied in the direction of wellbore/well components, mining fluid, earth cube drilling and mining, etc., can solve the problem of insufficient wetting of coal body

Active Publication Date: 2020-02-21
TAIYUAN UNIV OF TECH
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the defect of insufficient wetting of the coal body after water injection into the coal seam in the prior art, and combined with the electrodynamic characteristics of coal rock, through the joint action of dynamic pressure and electric field applied to the coal seam, the water can be adjusted under water injection pressure, electric field, etc. Under the action of the three driving forces of seepage force and capillary force, the coal can be quickly and effectively moved from the large cracks to the micro-pore cracks to fully wet the coal body, providing a pressure-dynamic-electric coupling to strengthen the coal seam water injection method

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
  • A Coal Seam Water Injection Method Enhanced by Pressure Dynamic-Electric Coupling
  • A Coal Seam Water Injection Method Enhanced by Pressure Dynamic-Electric Coupling
  • A Coal Seam Water Injection Method Enhanced by Pressure Dynamic-Electric Coupling

Examples

Experimental program
Comparison scheme
Effect test

Embodiment approach 1

[0025] Implementation of a method for enhanced coal seam water injection through pressure-electric coupling, the method is carried out in the following steps:

[0026] Step 1. The length of the working face of a mine is 150m, the thickness of the coal seam is 3.2m, and the type of coal mined is anthracite. The coal seam of a mine is drilled and sampled, and the uniaxial compressive strength of the coal sample is 7.36MPa, and the porosity is 3.82%. , water content 1.18%, water permeability coefficient 3.515×10 -4 cm 2 ·atm -1 ·s -1 , to determine the maximum water injection pressure 15MPa.

[0027] Step 2. Use the coal-rock electric-pneumatic triaxial seepage test device to measure the electric permeability coefficient of the coal sample to be 8.578×10 -4 cm 2 ·V -1 ·s -1 , using a micro-electrophoresis instrument to test the zeta potential of anthracite samples in aqueous solutions with different pH values, see attached image 3 , considering that the excessive pH of t...

Embodiment approach 2

[0033] Step 1. The length of the working face of a certain second mine is 200m, the thickness of the coal seam is 2.8m, and the mined coal is coking coal; the coal seam of a certain second mine is drilled and sampled, and the uniaxial compressive strength of the coal sample is determined to be 5.92MPa, and the porosity is 2.35%. , water content 1.64%, water permeability coefficient 1.906×10 -4 cm 2 ·atm -1 ·s -1 , to determine the maximum water injection pressure 16MPa.

[0034] Step 2. The electric permeability coefficient of the coal sample is determined to be 11.493×10 by using the coal-rock electric-pneumatic triaxial seepage test device -4 cm 2 ·V -1 ·s -1 , using a micro-electrophoresis instrument to test the zeta potential of coal samples in aqueous solutions with different pH values, see attached Figure 4 , considering that the excessive acidity and alkalinity of the coal sample will cause equipment corrosion, the pH of the injection solution is determined to b...

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 intensifying coal seam water injection through the pressing dynamic-electrodynamic coupling effect. A row of drilling holes are drilled in the positions, perpendicular to the coal wall, in an air inlet / return roadway, and a high-pressure water injection pipe and an electrode bar are arranged in each drilling hole; the water injection pipes in all the drilling holes are connected together through a high-pressure rubber hose; anode electrodes and cathode electrodes in the drilling holes are connected in series through insulated wires correspondingly; a directcurrent power supply is connected while water is injected into the drilling hole through the dynamic pressure; and coal seam water injection is intensified through the pressing dynamic-electrodynamiccoupling effect. According to the method, through the water injection pressure, electric osmosis acting force and capillary acting force, water is quickly driven from large cracks to micro hole cracks, efficient full wetting of coal bodies is achieved, after a coal reservoir is acted, the single hole wetting range is expanded, the water injection speed rate and the water content are increased, meanwhile, the drilling engineering quantity is further reduced greatly, economical, practical, simple, convenient and reliable effects are achieved, the effect is remarkable, and high application and popularization value is achieved.

Description

technical field [0001] The invention relates to a method for intensifying coal seam water injection, in particular to a method for intensifying coal seam water injection and fully wetting the coal body under the joint action of external dynamic pressure and electric field. Background technique [0002] With the increase of coal mining depth and the improvement of mechanized mining in our country, the output of coal dust at the working face has increased significantly, seriously affecting the physical and mental health of workers. Water injection through the coal seam can effectively reduce the amount of dust produced, and at the same time play a role in preventing rock impact, coal and gas outburst, and coal seam spontaneous combustion. However, the permeability of most coal reservoirs in my country is poor, and water injection is difficult. [0003] The existing method of strengthening coal seam water injection mainly starts from the following three aspects: one is to incr...

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
Patent Type & Authority Patents(China)
IPC IPC(8): E21B43/20
CPCE21B43/20
Inventor 郭俊庆康天合康健婷张惠轩张晓雨
Owner TAIYUAN UNIV OF TECH
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