Automatic energy storing high-pressure liquid injecting CO2 phase change pulse coal and rock body cracking method

A coal-rock mass and high-pressure liquid storage technology, which is applied in the field of CO2 phase change solid fracturing, can solve the problems of small fracturing range, inability to achieve continuous action, and low fracturing efficiency

Active Publication Date: 2017-07-14
TAIYUAN UNIV OF TECH
View PDF11 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] One is that the peak pressure duration of this method is short and continuous action cannot be achieved
The volume of the carbon dioxide burst tube is generally about 1.2L, and the liquid CO2 that can be accommodated 2 Very limited, the continuous injection time in one fracturing process is very short, the high pressure maintenance time is even shorter, only tens of milliseconds, the fracturing range is small, the effect is poor, and the fracturing efficiency is low
[0005] Second, this method is susceptible to interference during on-site construction. For example, the detonation line is easily interfered by the water in the coal seam, which leads to the failure of normal conduction detonation.

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
  • Automatic energy storing high-pressure liquid injecting CO2 phase change pulse coal and rock body cracking method
  • Automatic energy storing high-pressure liquid injecting CO2 phase change pulse coal and rock body cracking method
  • Automatic energy storing high-pressure liquid injecting CO2 phase change pulse coal and rock body cracking method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] (1) Drilling. A group of parallel boreholes were constructed along the vertical coal wall of the 15116 working face of a mine, a total of 11 holes, numbered 1 from left to right # ~11 # , the drilling diameter is 75mm, the hole depth is 30m, and the drilling spacing is 3m. 6 in the very center # The drilled holes are pre-splitting holes, and the remaining drilled holes are drainage holes. Immediately after the completion of the drilling construction, the drainage hole was sealed and extracted at a depth of 10.5m. After 20 days of negative pressure extraction, the first pulse fracturing test was carried out.

[0041] (2) vacuuming. Send the outlet end of the pipeline to a depth of 20m in the fracturing hole and seal the hole. Open stop valve 10, start vacuum pump 13, carry out degassing, record the pressure of vacuum gauge on the vacuum pump, when pressure value does not change, stop degassing, close stop valve 10.

[0042] (3) Liquid supply. Open the shut-off val...

Embodiment 2

[0050] (1) Prepare the sample. After fully mixing cement, sand, gypsum, and water in a mixer in a mass ratio of 8:20:1:4, make a sample of 1000mm×1000mm×800mm, and use a small vibrating rod to vibrate and tamp during the production process. Artificial maintenance for 21 days. The universal coefficient f of the sample is 3.4, and a cracking hole with a diameter Φ of 50 mm and a depth d of 500 mm is reserved in the sample.

[0051] (2) Seal the hole. Send the outlet end of the pipeline to a depth of 400mm in the fracturing hole, and use PD composite material to seal the hole with a sealing depth of 300mm.

[0052] (3) Ultrasonic speed measurement. Use an ultrasonic flaw detector to measure the ultrasonic wave velocity with the horizontal and vertical lines in the center of the borehole as the reference line, and measure the ultrasonic wave velocity at a measuring point with an interval of 50 mm up, down, and left and right. During the measurement, butter is used as the coupli...

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 an automatic energy storing high-pressure liquid injecting CO2 phase change pulse coal and rock body cracking method. Liquid state CO2 enters a high-pressure liquid injecting cylinder and a phase change chamber in the mode that the liquid state CO2 is injected into a high-pressure liquid storing temperature control tank, the liquid state CO2 in the phase change chamber is heated, the phase change pressure is increased, and gaseous CO2 enters the energy storing chamber to be subjected to automatic energy storing and a coal rock cracking chamber to be cracked; and when the pressure of the CO2 gas in the phase change chamber is decreased, the high-pressure CO2 gas enters the high-pressure liquid injecting cylinder to push a piston to expel the remaining CO2 gas, and enters the coal rock cracking chamber to be subjected to second-time cracking, the circulation of liquid injection, oil bath heating, phase change, energy storing and cracking is repeated, and continuous pulse high pressure flow jetting cracking is realized. According to the method, continuous pulse high pressure flow jetting cracking is realized, the time of cracking action is prolonged, the range of cracking action is expanded, the cracking effect is improved, and the method is suitable for quick and efficient cracking of solid materials such as coal, rock, concrete, soil and congelation.

Description

technical field [0001] The present invention relates to a CO 2 A phase-change solid cracking method, specifically a method that utilizes liquid CO 2 A method for fracturing coal and rock mass as a phase-change pressurized medium. Background technique [0002] With the rapid development of the national economy, the scale and quantity of engineering construction continue to expand, and the cracking of solid materials is involved in many engineering processes, such as in-situ directional cracking of rock mining in quarries, demolition of structures or buildings , Tunnel excavation, mining, broken roof of mining face or roadway, loosening and depressurization of coal and rock mass in high stress area, pipe wall cleaning, separation of frozen matter in alpine area, especially fracturing and permeability enhancement of low permeability oil and gas reservoirs, etc. , the cracking method will directly affect the progress, effect and safety of the project. At present, the methods ...

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 Applications(China)
IPC IPC(8): E21C37/14
CPCE21C37/14
Inventor 康天合张润旭赵国飞张晓雨
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