Leftover coal releasing device based on liquid carbon dioxide

Abstract

The utility model relates to a marginal coal releasing device based on liquid carbon dioxide, which belongs to the technical field of coal mining, and particularly comprises a carbon dioxide liquid storage tank, a plurality of carbon dioxide cracking carbon exhausters and a carbon dioxide filling machine, and the carbon dioxide cracking carbon exhausters are used for being mounted in cracking drill holes of marginal coal. The air inlet end of the carbon dioxide fracturing carbon exhauster is connected with a carbon dioxide filling machine through a carbon filling pipe, the carbon dioxide filling machine is connected with a carbon dioxide liquid storage tank, and the air exhaust end of the carbon dioxide fracturing carbon exhauster is connected with an adjacent goaf through a first connecting pipe. The exhaust end of the carbon dioxide fracturing carbon exhauster is further connected with a carbon dioxide filling mixer truck through a second connecting pipe, and the first connecting pipe and the second connecting pipe are provided with a first carbon exhaust control valve and a second carbon exhaust control valve respectively. According to the utility model, carbon dioxide in different states is fully utilized in a grading manner to release leftover coal, so that the safety degree of a leftover coal mining area is effectively improved.

Description

Technical Field

[0001] The utility model relates to a corner coal releasing device based on liquid carbon dioxide, belonging to the technical field of coal mining. Background Art

[0002] Coal mines leave behind a large number of irregular and scattered corner coals when mining coal resources. Corner coals are prone to collapse under the action of mining stress and ground stress, forming a large amount of floating coal accumulation. Since the end of the working face does not fall completely after the return column, it leaves air leakage channels, which are prone to spontaneous combustion. It can be seen that the existence of a large amount of corner coals may cause power disasters, cause hidden dangers of spontaneous combustion, and lead to a large waste of coal resources.

[0003] At present, the mining of relatively large-sized marginal coal is mainly carried out by continuous mining, fully mechanized mining, and lane mining, while the extremely irregular marginal coal with small area and reserves, such as arc, triangle or sawtooth, which cannot be arranged with regular working faces by comprehensive mechanization, is often abandoned. The main reasons are the difficulty of working face arrangement, the large number of various equipment, the high mining cost, and the existence of safety risks. Therefore, it is extremely important to adopt safe, convenient and feasible methods to mine the residual marginal coal in the mine.

[0004] Solid carbon dioxide is also called dry ice. Dry ice energy rock breaking technology uses the chemical reaction between the energy-gathering agent and carbon dioxide to convert solid carbon dioxide into gaseous carbon dioxide. The phase change process will cause a 600-800 times volume expansion to achieve the purpose of cracking rocks. Compared with liquid carbon dioxide blasting technology, the volume expansion rate is greater. In addition, solid carbon dioxide is relatively convenient to store and transport than liquid carbon dioxide.

[0005] "Research on the Application of Dry Ice Energy Rock Breaking Technology in Tunnel Excavation" published in the Journal of Underground Space and Engineering, Issue 6, 2023, points out that dry ice rock breaking technology has been used in open-pit foundation pits and slope projects. Its rock breaking efficiency is significantly higher than that of mechanical excavation, and it is increasingly used as an effective supplement to traditional rock breaking technologies such as mechanical rock breaking and explosive blasting.

[0006] The Chinese utility model patent with application date of November 15, 2022 and publication number CN115823977A provides a method for efficiently cracking rocks with dry ice, providing a method for cracking rocks that does not require laying cables, can be remotely started, and has better safety and simplicity.

[0007] The Chinese utility model patent with application date of May 8, 2017 and publication number CN106930744A provides a millisecond multi-stage directional blasting dry ice fracturing method and blasting tube, which can effectively control the number of cracks generated, increase the distance of crack extension without causing serious damage to the hole wall, and improve the gas extraction efficiency.

[0008] The Chinese utility model patent with application date of December 28, 2017 and publication number CN207816108U provides a solid carbon dioxide blasting device, which solves the problem of inconvenient fixing of existing equipment.

[0009] The Chinese utility model patent with application date of March 30, 2022 and publication number CN114811404A provides a portable device for storing carbon dioxide underground in coal mines and its use method. The gaseous carbon dioxide formed by the leakage of solid carbon dioxide in the working body can inertify the residual coal in the goaf for fire prevention and fire extinguishing.

[0010] However, existing research and utility models are only applicable to conventional coal mining activities, and do not pay attention to the particularities of edge coal mining, especially the low utilization of carbon dioxide (the use of carbon dioxide for fracturing, blasting, fire prevention and extinguishing, and carbon fixation has not been effectively combined), and there is a lack of prevention methods for using carbon dioxide to simultaneously respond to dynamic disasters and spontaneous combustion. It cannot be applied to the release of "extremely irregular edge coal resources such as arc, triangular or sawtooth shapes with small areas and reserves, and which cannot be arranged into regular working faces using comprehensive mechanization." Utility Model Content

[0011] In order to solve the technical problems existing in the prior art, the utility model provides a marginal coal release device based on liquid carbon dioxide, which can fully and gradedly utilize carbon dioxide in different states to release marginal coal and effectively improve the safety level of marginal coal mining areas.

[0012] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is a device for releasing marginal coal based on liquid carbon dioxide, including a carbon dioxide storage tank, a carbon dioxide fracturing carbon remover and a carbon dioxide filling machine. A plurality of the carbon dioxide fracturing carbon removers are used to be installed in the fracturing boreholes of marginal coal. The air inlet end of the carbon dioxide fracturing carbon remover is connected to the carbon dioxide filling machine through a carbon filling pipe. The carbon dioxide filling machine is connected to the carbon dioxide storage tank. The exhaust end of the carbon dioxide fracturing carbon remover is connected to the adjacent goaf through a first connecting pipe. The exhaust end of the carbon dioxide fracturing carbon remover is also connected to a carbon dioxide filling mixer truck through a second connecting pipe. The first connecting pipe and the second connecting pipe are respectively equipped with a first carbon removal control valve and a second carbon removal control valve.

[0013] Preferably, the carbon dioxide induced cracking carbon remover comprises a mounting tube, a carbon exhaust fan, an air bag and a pressure relief terminal. A plurality of air guide grooves are arranged on the outer tube wall of the mounting tube. A pressure relief terminal is arranged on the front end of the mounting tube, and a carbon charging connecting terminal is arranged on the rear end. A carbon exhaust fan and a carbon charging connecting joint are also arranged on the carbon charging connecting end. The carbon charging connecting joint is connected to the carbon charging tube. An air bag is sleeved on the outside of the carbon exhaust fan. A carbon exhaust main pipe is arranged on the air bag. A first connecting pipe and a second connecting pipe are respectively connected to the carbon exhaust main pipe. A carbon storage tank is arranged in the mounting tube. The carbon storage tank is arranged on the carbon charging connecting terminal. A heating device is arranged in the carbon storage tank, and one end is open and a pressure relief diaphragm is arranged thereon. The carbon storage tank is filled with liquid carbon dioxide. The carbon exhaust fan, the heating device, the first carbon exhaust control valve and the second carbon exhaust control valve are respectively connected to the central controller.

[0014] Preferably, the carbon exhaust fan is an axial flow fan, and a carbon dioxide concentration sensor is installed at the air inlet end.

[0015] Compared with the prior art, the utility model has the following technical effects: the utility model implements multi-stage graded utilization of carbon dioxide in different states in view of the particularity of marginal coal mining, and the safety level of the marginal coal mining area is significantly improved. First, the roof is cracked by liquid carbon dioxide, which transfers or reduces the pressure of the roof overlying the marginal coal. The high-concentration carbon dioxide gas cools, inerts, and suppresses explosions in the adjacent goaf, and simultaneously eliminates the hidden dangers of power disasters and spontaneous combustion. The low-concentration carbon dioxide gas is combined with a filling body containing an alkaline admixture to achieve carbon fixation and sealing. The entire process can be achieved through a set of devices, which can be remotely controlled and have good safety, convenience and economy. It realizes the coordinated and efficient circulation of liquid carbon dioxide to eliminate power disasters, high-concentration carbon dioxide gas to eliminate the hidden dangers of spontaneous combustion, liquid carbon dioxide coal mining, and low-concentration carbon dioxide carbon fixation, and scientifically releases the marginal coal resources of each block section of the mine, and the operation is safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the utility model;

[0017] Figure 2 This is a schematic diagram of the structure of the carbon dioxide cracking and carbon removal device in the utility model; DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] like Figure 1and Figure 2 As shown, a device for releasing marginal coal based on liquid carbon dioxide comprises a carbon dioxide storage tank 1, a carbon dioxide fracturing carbon remover 2 and a carbon dioxide filling machine 3. A plurality of carbon dioxide fracturing carbon removers 2 are used to be installed in the fracturing boreholes of marginal coal. The air inlet end of the carbon dioxide fracturing carbon remover 2 is connected to the carbon dioxide filling machine 3 via a carbon filling pipe 17. The carbon dioxide filling machine 3 is connected to the carbon dioxide storage tank 1. The exhaust end of the carbon dioxide fracturing carbon remover 2 is connected to the adjacent goaf 5 via a first connecting pipe 4. The exhaust end of the carbon dioxide fracturing carbon remover 2 is also connected to a carbon dioxide filling mixer truck 7 via a second connecting pipe 6. The first connecting pipe 4 and the second connecting pipe 6 are respectively provided with a first carbon removal control valve 8 and a second carbon removal control valve 9.

[0020] The carbon dioxide cracking carbon remover 2 in the utility model can be filled by the carbon dioxide liquid storage tank 1 and the carbon dioxide filling machine 3. The carbon dioxide cracking carbon remover 2 blasts the corner coal by the explosive impact force of the internal filling material. At the same time, the generated carbon dioxide gas is collected and processed by the first connecting pipe 3 and the second connecting pipe 5.

[0021] The carbon dioxide cracking carbon remover 2 includes a mounting tube 10, a carbon exhaust fan 11, an air bag 12 and a pressure relief terminal 13. A plurality of air guide grooves 14 are arranged on the outer tube wall of the mounting tube 10. The front end of the mounting tube 10 is equipped with a pressure relief terminal 13, and the rear end is equipped with a carbon charging connection terminal 15. The carbon charging connection terminal 15 is also equipped with a carbon exhaust fan 11 and a carbon charging connection joint 16. The carbon charging connection joint 16 is connected to the carbon charging tube 17. The outer part of the carbon exhaust fan 11 is covered with an air bag 12. The air bag 1 A carbon exhaust main pipe 18 is installed, and the first connecting pipe 4 and the second connecting pipe 5 are respectively connected to the carbon exhaust main pipe 18. A carbon storage tank 19 is installed in the installation pipe 10, and the carbon storage tank 19 is installed on the carbon charging connection terminal 15. A heating device 20 is installed in the carbon storage tank 19, and one end is open and a pressure relief diaphragm 21 is installed. The carbon storage tank 19 is filled with liquid carbon dioxide. The carbon exhaust fan 11, the heating device 20, the first carbon exhaust control valve 8 and the second carbon exhaust control valve 9 are respectively connected to the central controller.

[0022] The carbon dioxide fracturing carbon remover is a tubular structure, with a carbon storage tank 19 installed inside, a heating device 20 installed inside the carbon storage tank 19 and filled with liquid carbon dioxide, a carbon filling connection terminal 16 and a pressure relief terminal 13 installed at both ends of the installation tube 10, the installation tube 10 is sealed, and an air guide groove 14 is arranged on the outer circumference of the installation tube 10, and the air guide groove 14 is arranged along the length direction of the installation tube 10, which is used to smoothly suck carbon dioxide into the air bag 12 when the carbon dioxide fracturing carbon remover 2 is inserted in the borehole. The carbon exhaust fan 11 is used to extract the carbon dioxide gas in the borehole, suck the carbon dioxide gas into the air bag, and transport it to the adjacent goaf 5 or the carbon dioxide filling mixer 7 as needed. The carbon exhaust fan 11 is an axial flow fan, and a carbon dioxide concentration sensor 22 is installed at the air inlet end. The carbon dioxide concentration sensor 22 can detect the concentration of carbon dioxide in real time, and the central controller controls the first carbon exhaust control valve 8 and the second carbon exhaust control valve 9 according to the concentration of carbon dioxide.

[0023] In specific use, the carbon dioxide fracturing carbon remover 2 is installed in the fracturing drill hole of the corner coal, and the fracturing drill hole is blocked to prevent the leakage of carbon dioxide gas and the occurrence of punching after fracturing; the carbon dioxide fracturing carbon remover can be connected in parallel or in series, and can be selected according to the hole depth; the central controller controls the heating device to heat, and the heat generated by the heating device heats the liquid carbon dioxide, so that the liquid carbon dioxide is rapidly gasified, and the volume expands 400-600 times, generating a large amount of high-pressure gas. When the pressure exceeds the limit of the pressure relief diaphragm, the pressure relief diaphragm breaks, and the carbon dioxide gas rushes out through the pressure relief end to fracture the surrounding rock mass;

[0024] 3-6 milliseconds after the solid carbon dioxide is fractured, the carbon exhaust fan is started to inflate the airbag and fill the top plate fracture drilling hole. At the same time, the carbon exhaust fan sucks the carbon dioxide gas in the top plate fracture drilling hole into the airbag through the air guide groove. During this process, a carbon dioxide concentration sensor detects the carbon dioxide concentration in real time.

[0025] When the carbon dioxide concentration is greater than 34%, the first carbon discharge control valve is opened, and the carbon dioxide gas is discharged into the adjacent goaf 4 to achieve cooling, inerting, and explosion suppression of the goaf;

[0026] When the carbon dioxide concentration is less than 34% and greater than 0.5%, close the first carbon discharge control valve, open the second carbon discharge control valve, and discharge the carbon dioxide gas into the carbon dioxide filling mixer truck;

[0027] When the carbon dioxide concentration is less than 0.5%, close the carbon exhaust fan, the first carbon exhaust control valve, and the second carbon exhaust control valve, take out the carbon dioxide fracturing carbon exhaust device from the roof fracturing drilling hole, and refill the carbon dioxide fracturing carbon exhaust device through the solid-state carbon dioxide storage vehicle;

[0028] Repeat the above steps until all the corner coal is removed.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the scope of the present invention.

Claims

1. A device for releasing corner coal based on liquid carbon dioxide, characterized in that: It includes a carbon dioxide storage tank, a carbon dioxide fracturing carbon remover and a carbon dioxide filling machine. A plurality of the carbon dioxide fracturing carbon removers are used to be installed in the fracturing boreholes of marginal coal. The air inlet end of the carbon dioxide fracturing carbon remover is connected to the carbon dioxide filling machine through a carbon filling pipe. The carbon dioxide filling machine is connected to the carbon dioxide storage tank. The exhaust end of the carbon dioxide fracturing carbon remover is connected to the adjacent goaf through a first connecting pipe. The exhaust end of the carbon dioxide fracturing carbon remover is also connected to a carbon dioxide filling mixer truck through a second connecting pipe. The first connecting pipe and the second connecting pipe are respectively equipped with a first carbon removal control valve and a second carbon removal control valve.

2. A device for releasing corner coal based on liquid carbon dioxide according to claim 1, characterized in that: The carbon dioxide cracking carbon exhaust device includes a mounting tube, a carbon exhaust fan, an air bag and a pressure relief terminal. A plurality of air guide grooves are arranged on the outer tube wall of the mounting tube. A pressure relief terminal is arranged at the front end of the mounting tube, and a carbon charging connecting terminal is arranged at the rear end. A carbon exhaust fan and a carbon charging connecting joint are also arranged on the carbon charging connecting terminal. The carbon charging connecting joint is connected to the carbon charging tube. An air bag is sleeved on the outside of the carbon exhaust fan. A carbon exhaust main pipe is arranged on the air bag. A first connecting pipe and a second connecting pipe are respectively connected to the carbon exhaust main pipe. A carbon storage tank is arranged in the mounting tube. The carbon storage tank is arranged on the carbon charging connecting terminal. A heating device is arranged in the carbon storage tank, and one end is open and a pressure relief diaphragm is arranged therein. The carbon storage tank is filled with liquid carbon dioxide. The carbon exhaust fan, the heating device, the first carbon exhaust control valve and the second carbon exhaust control valve are respectively connected to a central controller.

3. A device for releasing corner coal based on liquid carbon dioxide according to claim 2, characterized in that: The carbon exhaust fan is an axial flow fan, and a carbon dioxide concentration sensor is installed at the air inlet end.

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