CN212003131U - Enhanced gas extraction system applying hot steam and microwave radiation in cooperation with permeability-increasing coal seam - Google Patents
Enhanced gas extraction system applying hot steam and microwave radiation in cooperation with permeability-increasing coal seam Download PDFInfo
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- CN212003131U CN212003131U CN202020446540.3U CN202020446540U CN212003131U CN 212003131 U CN212003131 U CN 212003131U CN 202020446540 U CN202020446540 U CN 202020446540U CN 212003131 U CN212003131 U CN 212003131U
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Abstract
The utility model discloses an enhanced gas extraction system of an anti-reflection coal seam cooperated with hot steam and microwave radiation, which belongs to the technical field of mining, and comprises a gas extraction branch pipe arranged in an extraction drill hole, and a steam transmission pipe and a microwave antenna arranged in the anti-reflection drill hole, wherein the other end of the gas extraction branch pipe is communicated with a gas extraction system pipe network; the other end of the steam transmission pipe is connected with a steam generator; the microwave antenna is connected with the microwave generator through the coaxial waveguide; the plurality of extraction drill holes are formed around the anti-reflection drill hole; and plugging is arranged at the orifices of the extraction drill hole and the anti-reflection drill hole. The coal bed is anti-reflection by injecting hot steam, so that the coal body structure is improved and the gas desorption seepage is promoted; after the water vapor is condensed into liquid water due to heat transfer, the liquid water is quickly gasified into high-temperature high-pressure steam under the heating of microwaves, the permeability increasing coal layer is continuously increased, the water lock effect is eliminated, the coal pore crack rate and a gas flow channel are improved, and meanwhile, the gas desorption seepage is further promoted under the dual effects of the high temperature and the adsorption advantage of the steam.
Description
Technical Field
The utility model belongs to the technical field of the mining, especially, relate to an use intensive gas drainage system in hot steam and microwave radiation anti-reflection coal seam in coordination.
Background
The coal bed gas resources in China are rich, but the coal bed gas resources generally have the characteristic of high storage and low permeability, and the development of the coal bed gas industry and the safe and efficient exploitation of coal resources in China are severely restricted. Practice proves that the gas extraction of the low-permeability coal seam can be obviously enhanced by adopting the coal seam permeability increasing technology. In recent years, a variety of permeability-increasing methods have been proposed, such as techniques of hydraulic punching, hydraulic fracturing, and the like.
In the hydraulic punching technology, a rock pillar or a coal pillar is used as a safety barrier, and high-pressure water jet is used for impacting coal around a drilled hole to punch out a large amount of coal, so that holes are formed. Due to the action of ground stress, the coal body around the holes is greatly displaced, so that the coal body around the holes is fully decompressed, the air permeability coefficient is increased, and the gas in the coal body is greatly released. However, the pure water jet has high water pressure and poor impact effect; although the abrasive jet can obviously improve the impact effect, a series of problems such as nozzle damage, hole blockage and the like can be caused; the hydraulic fracturing technology is constructed under the action of high flow and high water pressure, so that local stress concentration is easily caused, and meanwhile, the requirements on matched technical equipment and safety measures are high. In addition, no matter hydraulic punching or hydraulic fracturing technology, a large amount of liquid water can be caused to invade coal bodies, the water locking effect is easily caused, the gas flow channel is blocked, and efficient extraction of coal seam gas is not facilitated.
Although the technologies have certain application effects, the technologies have obvious limitations, and therefore, research and development of novel coal seam permeability increasing and strengthening gas extraction technologies suitable for different engineering conditions are needed.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that to the not enough of above-mentioned prior art, provide an use hot steam and microwave radiation in coordination with the gas drainage system of reinforceing of anti-reflection coal seam, can reach the anti-reflection gas drainage effect of reinforceing of efficient coal seam.
In order to solve the technical problem, the utility model discloses the technical scheme who takes is:
a reinforced gas extraction system for a coal seam with an anti-reflection function by using hot steam and microwave radiation in a synergic mode comprises a gas extraction branch pipe arranged in an extraction drill hole, and a steam transmission pipe and a microwave antenna which are arranged in the anti-reflection drill hole, wherein the other end of the gas extraction branch pipe is communicated with a gas extraction system pipe network outside the extraction drill hole; the other end of the steam transmission pipe is connected with a steam generator outside the anti-reflection drill hole; the microwave antenna is connected with a microwave generator outside the anti-reflection drill hole through a coaxial waveguide; the extraction drill holes are arranged on the periphery of the anti-reflection drill hole and are parallel to the anti-reflection drill hole and are arranged at intervals; the orifices of the extraction drill hole and the anti-reflection drill hole are provided with plugs, the gas extraction branch pipe penetrates through the plugs of the orifices of the extraction drill holes, and the steam transmission pipe and the coaxial waveguide penetrate through the plugs of the orifices of the anti-reflection drill holes.
Preferably, protective tubes are arranged outside the coaxial waveguide and the microwave antenna and penetrate through the anti-reflection drill hole to block the hole opening.
Preferably; and a water collector is arranged on a pipeline between the exposed end of the gas extraction branch pipe and the gas extraction system pipe network, and two ends of the water collector are respectively provided with a stop valve.
Preferably, the exposed end of the coaxial waveguide is connected with a waveguide converter, and the waveguide converter is connected with a microwave generator through a rectangular waveguide.
Preferably, a steam pressure meter and a high-temperature stop valve are arranged on a pipeline between the exposed end of the steam transmission pipe and the steam generator.
Preferably, the temperature of the water vapor in the steam transmission pipe is not lower than 150 ℃ and the pressure is not lower than 0.7 MPa.
Preferably, 4-6 extraction drill holes are formed, and the distance between each extraction drill hole and the corresponding anti-reflection drill hole is 3-5 m.
Preferably, the extraction drill hole and the anti-reflection drill hole sequentially penetrate through the coal seam floor and the coal seam and extend to the coal seam roof at the other end of the coal seam, and the tail ends of the extraction drill hole and the anti-reflection drill hole extend to the coal seam roof by 0.5 +/-0.1 m.
Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: compared with the prior art, the utility model adopts the heat-injection steam anti-reflection coal layer, improves the coal body structure and promotes the gas desorption seepage; after the water vapor is gradually condensed into liquid water due to heat transfer and dissipation, the liquid water can be quickly gasified and form high-temperature and high-pressure steam again under the assistance of microwave heating, the permeability-increasing coal bed is continuously increased, the water lock effect is eliminated, the pore porosity of the coal body is improved, a gas flow channel is increased, and meanwhile, the gas desorption seepage can be further promoted under the dual actions of the high temperature and the adsorption advantage of the steam. The utility model discloses to annotate hot steam and combine together with microwave radiation, improved mine gas and taken out technical means, it is significant to the safe high-efficient exploitation that improves coal resource. The utility model discloses the method is simple, and construction convenience can effectively improve coal seam gas drainage effect, has extensive application in this technical field.
Drawings
Fig. 1 is a schematic structural diagram of a reinforced gas extraction system using hot steam and microwave radiation in cooperation with an anti-reflection coal seam according to an embodiment of the present invention;
in the figure: 1. a coal seam; 2. a coal seam floor; 3. a coal seam roof; 4. extracting and drilling; 5. drilling for anti-reflection; 6. a gas extraction branch pipe; 7. a steam delivery pipe; 8. a microwave antenna; 9. a coaxial waveguide; 10. a protective tube; 11. a waveguide converter; 12. a rectangular waveguide; 13. a microwave generator; 14. a high temperature stop valve; 15. a steam pressure gauge; 16. a steam generator; 17. a stop valve; 18. a water collector; 19. plugging; 20. gas drainage system pipe network.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1, the utility model provides an use intensive gas drainage system in hot steam and microwave radiation cooperation anti-reflection coal seam, including setting up in the gas drainage branch pipe 6 of taking out in the drilling 4 and setting up steam transmission pipe 7 and microwave antenna 8 in the anti-reflection drilling 5, the other end of gas drainage branch pipe 6 communicates with the gas drainage system pipe network 20 of taking out the drilling 4 outside; the other end of the steam transmission pipe 7 is connected with a steam generator 16 outside the anti-reflection drilling hole 5; the microwave antenna 8 is connected with a microwave generator 13 outside the anti-reflection drill hole 5 through a coaxial waveguide 9; the extraction drill holes 4 are multiple and arranged around the anti-reflection drill hole 5, and the extraction drill holes 4 are parallel to the anti-reflection drill hole 5 and are arranged at intervals; the orifices of the extraction drill hole 4 and the anti-reflection drill hole 5 are respectively provided with a plug 19, the gas extraction branch pipe 6 penetrates through the plugs 19 of the orifices of the extraction drill hole 4, and the steam transmission pipe 7 and the coaxial waveguide 9 penetrate through the plugs 19 of the orifices of the anti-reflection drill hole 5.
As a preferred structure, as shown in fig. 1, a shielding tube 10 is arranged outside the coaxial waveguide 9 and the microwave antenna 8, and the shielding tube 10 penetrates through a plug 19 of an orifice of the anti-reflection drilling hole 5. The exposed end of the coaxial waveguide 9 is connected with a waveguide converter 11, and the waveguide converter 11 is connected with a microwave generator 13 through a rectangular waveguide 12. And opening the microwave generator, enabling the generated microwaves to sequentially pass through the rectangular waveguide, the waveguide converter and the coaxial waveguide, and finally reaching the microwave antenna and transmitting the microwaves to the anti-reflection drill hole.
In a specific embodiment of the present invention, as shown in fig. 1, a water collector 18 is disposed on the pipeline between the exposed end of the gas extraction branch pipe 6 and the gas extraction system pipe network 20, and stop valves 17 are disposed at two ends of the water collector 18 respectively. The water contained in the extracted gas is collected through the water collector, and the purity of the gas is improved.
Because the temperature of the high-temperature steam output by the steam generator is very high, the steam pressure gauge 15 and the high-temperature stop valve 14 are arranged on the pipeline between the exposed end of the steam transmission pipe 7 and the steam generator 16, so that whether the parameter of the high-temperature steam output by the steam generator meets the process requirement or not can be monitored conveniently in real time. Specifically, the temperature of the steam in the steam transmission pipe 7 is not lower than 150 ℃ and the pressure is not lower than 0.7 MPa.
During specific construction, 4-6 extraction drill holes 4 are formed, and the distance between each extraction drill hole 4 and the corresponding anti-reflection drill hole 5 is 3-5 m. The extraction drill holes 4 and the anti-reflection drill holes 5 sequentially penetrate through the coal seam floor 2 and the coal seam 1 and extend to the coal seam roof 3 at the other end of the coal seam, and the depths of the extraction drill holes 4 and the anti-reflection drill holes 6 extending to the coal seam roof 3 are 0.5 +/-0.1 m.
The utility model discloses an utilize heat injection steam technique and microwave radiation technique to the coal seam anti-reflection, hot steam pours into the coal seam and can promote coal body hole crack to develop, improve coal seam gas flow path into to promote coal seam gas desorption under the adsorbed dual function of high temperature and vapor advantage, thereby reach the effect of reinforceing gas drainage. The thermal stress generated by microwave radiation can promote gas desorption, effectively damage coal bodies and obviously expand gas flowing space. As water is an important factor influencing the microwave radiation thermal effect of the coal body, the anti-reflection rate of the coal body after microwave radiation tends to increase exponentially along with the increase of the water content of the coal body. The utility model discloses realize effectively combining two kinds of techniques, reach more efficient coal seam anti-reflection and reinforce gas drainage effect.
The utility model discloses an operating principle is exactly to pour into the coal seam into hot steam, promotes coal seam gas desorption, can condense gradually for liquid water after high temperature high pressure steam gives coal seam and gas with heat transfer, and the thermal stress that rethread microwave radiation produced makes liquid water gasify rapidly and forms high temperature high pressure steam, continues to send and splits the coal seam, promotes the gas desorption, avoids liquid water to cause the water lock effect, forms the shutoff to gas flow path to the phenomenon that is unfavorable for coal seam gas to take out takes place.
The utility model discloses use heat injection steam and microwave in coordination with anti-reflection coal seam's intensive gas drainage method, including following step:
a. and constructing anti-reflection drill holes 5 penetrating through the coal seam bottom plate 2 and reaching the coal seam 1 to the coal seam top plate 3 in the extraction roadway, constructing 4-6 extraction drill holes 4 at positions 3-5 m away from the peripheries of the anti-reflection drill holes 5 in the same mode, and constructing the anti-reflection drill holes 5 and the extraction drill holes 4 about 0.5m into the coal seam top plate 3.
b. Sending the gas extraction branch pipe 6 to the coal seam 1 section of the extraction drill hole 4; and (3) sending the microwave antenna 8 connected to the front end of the coaxial waveguide 9 into the bottom end of the protective pipe 10, sending the microwave antenna and the steam transmission pipe 7 into the coal seam 1 section of the anti-reflection drill hole 5, and then sealing the extraction drill hole 4 and the anti-reflection drill hole 5 according to the conventional method.
c. Sequentially connecting the exposed end of the coaxial waveguide 9 with a waveguide converter 11, a rectangular waveguide 12 and a microwave generator 13; the exposed end of the steam transmission pipe 7 is connected with a steam generator 16, and a high-temperature stop valve 14 and a steam pressure gauge 15 are arranged on the connecting pipeline.
d. Sequentially connecting the exposed end of the gas extraction branch pipe 6 with a water collector 18 and a gas extraction system pipe network 20, and respectively arranging stop valves 17 on connecting pipelines at two ends of the water collector 18; and opening a stop valve 17 and a stop valve 19 on the gas extraction pipeline, and starting gas extraction.
e. And starting a steam generator 16, opening a high-temperature stop valve 14 arranged on the pipeline, injecting high-temperature steam with the temperature not lower than 150 ℃ and the pressure not lower than 0.7MPa into the anti-reflection drill hole 5 to increase the permeability of the coal bed, monitoring the steam pressure change in the anti-reflection drill hole 5 through a steam pressure gauge 15, determining that the steam pressure reaches a preset value, and closing the high-temperature stop valve 14 and the steam generator 16 in sequence after maintaining the steam pressure not lower than 1 h.
f. When the temperature of the outer end pipe wall of the steam transmission pipe 7 is reduced to 50-60 ℃, the steam in the anti-reflection drill hole 5 is judged to be gradually condensed into liquid water, the microwave generator 13 can be started to transmit microwave signals to the microwave antenna 8 through the rectangular waveguide 12, the waveguide converter 11 and the coaxial waveguide 9 and radiate the peripheral coal bed of the anti-reflection drill hole 5, so that the liquid water is quickly gasified to form high-temperature and high-pressure steam, the coal bed is continuously fractured, the gas desorption seepage is promoted, and the gas is displaced to be transported to the extraction drill hole 4.
g. And e, repeating the steps e and f, performing circulation operation of heat injection steam and microwave radiation, and continuously enhancing coal seam gas extraction.
The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.
Claims (8)
1. A reinforced gas extraction system using hot steam and microwave radiation in cooperation with an anti-reflection coal seam is characterized in that: the gas extraction system comprises a gas extraction branch pipe arranged in an extraction drill hole, and a steam transmission pipe and a microwave antenna which are arranged in an anti-reflection drill hole, wherein the other end of the gas extraction branch pipe is communicated with a gas extraction system pipe network outside the extraction drill hole; the other end of the steam transmission pipe is connected with a steam generator outside the anti-reflection drill hole; the microwave antenna is connected with a microwave generator outside the anti-reflection drill hole through a coaxial waveguide; the extraction drill holes are arranged on the periphery of the anti-reflection drill hole and are parallel to the anti-reflection drill hole and are arranged at intervals; the orifices of the extraction drill hole and the anti-reflection drill hole are provided with plugs, the gas extraction branch pipe penetrates through the plugs of the orifices of the extraction drill holes, and the steam transmission pipe and the coaxial waveguide penetrate through the plugs of the orifices of the anti-reflection drill holes.
2. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 1, is characterized in that: and protective tubes are arranged outside the coaxial waveguide and the microwave antenna and penetrate through the anti-reflection drill hole to be plugged.
3. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 1, is characterized in that: and a water collector is arranged on a pipeline between the exposed end of the gas extraction branch pipe and the gas extraction system pipe network, and two ends of the water collector are respectively provided with a stop valve.
4. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 1, is characterized in that: the exposed end of the coaxial waveguide is connected with a waveguide converter, and the waveguide converter is connected with a microwave generator through a rectangular waveguide.
5. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 1, is characterized in that: and a steam pressure meter and a high-temperature stop valve are arranged on a pipeline between the exposed end of the steam transmission pipe and the steam generator.
6. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 1, is characterized in that: the temperature of the steam in the steam transmission pipe is not lower than 150 ℃, and the pressure is not lower than 0.7 MPa.
7. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of any one of claims 1-6, is characterized in that: the number of the extraction drill holes is 4-6, and the distance between the extraction drill holes and the anti-reflection drill holes is 3-5 m.
8. The system for enhancing gas extraction of the coal seam with the cooperation of hot steam and microwave radiation and permeability increasing of the coal seam according to claim 7, is characterized in that: the extraction drill hole and the anti-reflection drill hole sequentially penetrate through the coal seam bottom plate and the coal seam and extend to the coal seam top plate at the other end of the coal seam, and the tail ends of the extraction drill hole and the anti-reflection drill hole extend to the coal seam top plate by 0.5 +/-0.1 m.
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| CN202020446540.3U CN212003131U (en) | 2020-03-31 | 2020-03-31 | Enhanced gas extraction system applying hot steam and microwave radiation in cooperation with permeability-increasing coal seam |
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| CN202020446540.3U CN212003131U (en) | 2020-03-31 | 2020-03-31 | Enhanced gas extraction system applying hot steam and microwave radiation in cooperation with permeability-increasing coal seam |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113027403A (en) * | 2021-05-27 | 2021-06-25 | 中国煤炭地质总局勘查研究总院 | Method for injecting hot steam into coal seam and electronic equipment |
| CN113216962A (en) * | 2021-06-28 | 2021-08-06 | 河南理工大学 | Synergistic permeability-increasing desorption-promoting experimental system and method for ultrasonic-activated fracturing fluid |
| CN113389523A (en) * | 2021-06-11 | 2021-09-14 | 华能煤炭技术研究有限公司 | Controllable shock wave anti-reflection and carbon dioxide displacement combined gas extraction method and equipment |
| CN114320257A (en) * | 2021-12-30 | 2022-04-12 | 中国矿业大学 | Closed-loop system and method for enhanced extraction of heat injection coal seam after underground gas combustion of coal mine |
| CN115434671A (en) * | 2022-09-10 | 2022-12-06 | 中国矿业大学 | Coal seam pressure relief and permeability increasing method and system |
-
2020
- 2020-03-31 CN CN202020446540.3U patent/CN212003131U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113027403A (en) * | 2021-05-27 | 2021-06-25 | 中国煤炭地质总局勘查研究总院 | Method for injecting hot steam into coal seam and electronic equipment |
| CN113389523A (en) * | 2021-06-11 | 2021-09-14 | 华能煤炭技术研究有限公司 | Controllable shock wave anti-reflection and carbon dioxide displacement combined gas extraction method and equipment |
| CN113216962A (en) * | 2021-06-28 | 2021-08-06 | 河南理工大学 | Synergistic permeability-increasing desorption-promoting experimental system and method for ultrasonic-activated fracturing fluid |
| CN113216962B (en) * | 2021-06-28 | 2023-11-17 | 河南理工大学 | Synergistic anti-reflection desorption promotion experimental system and method for ultrasonic activated fracturing fluid |
| CN114320257A (en) * | 2021-12-30 | 2022-04-12 | 中国矿业大学 | Closed-loop system and method for enhanced extraction of heat injection coal seam after underground gas combustion of coal mine |
| CN114320257B (en) * | 2021-12-30 | 2023-11-03 | 中国矿业大学 | Closed loop system and method for enhanced extraction of coal seam after burning of underground coal mine gas |
| CN115434671A (en) * | 2022-09-10 | 2022-12-06 | 中国矿业大学 | Coal seam pressure relief and permeability increasing method and system |
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