Gas injection displacement flow increasing gas extraction pipeline quick connection system and gas injection method thereof

Abstract

The invention discloses a gas injection displacement flow-increasing gas extraction pipeline quick connecting system which comprises a gas injection device, a filtering device and a gas metering device, a gas injection opening of the gas injection device is connected with a gas injection hole sealing pipe, and a gas inlet of the gas injection device is connected with a gas injection main pipe in an underground coal mine. A gas inlet of the filtering device is connected with an extraction hole sealing pipe of the gas extraction system, a gas outlet of the filtering device is connected with a gas inlet of the gas metering device, and the gas outlet of the filtering device is connected with an extraction main pipe in an underground roadway of a coal mine. The front filter and the sealed water tank are arranged at the front end of the multi-parameter gas meter and the front end of the gas meter, the problem that equipment is damaged due to the fact that impurities such as pulverized coal and condensate water in a pipeline enter the multi-parameter gas meter and the gas meter is solved, the resistance of an extraction system is not affected, and therefore accurate measurement for increasing the gas flow is achieved. The pipelines are all of a quick connection structure, firstly, the sealing effect is guaranteed, and the production efficiency is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of underground coal mine gas extraction, and in particular relates to a gas injection displacement flow-increasing gas extraction pipeline quick connection system and a gas injection method thereof. Background Art

[0002] Coal is the primary fossil energy in my country, and its consumption accounts for more than 50% of the total primary energy consumption. There are many harmful factors in the process of coal mining, such as gas, fire, dust, water damage, etc., among which gas is the biggest threat to mine safety production. At present, gas extraction technology in coal mine areas is the main way to control coal seam gas disasters. Extracting gas stored in coal seams can better solve problems such as abnormal gas outburst and coal and gas outburst. However, field practice has found that poor coal seam permeability is the main reason restricting the effect of gas extraction. The problem of low permeability of coal seams can be solved by hydraulic fracturing and hydraulic cutting, but due to the large differences in coal seam storage conditions in different mines, various problems will still occur during the extraction process. And whether the gas extraction meets the standards must be strictly and accurately measured. Since the extracted coal seam gas airflow often contains a certain amount of water, coal powder and other substances, there are problems of increasing pipe network resistance and increasing errors.

[0003] In my country, the underground enhanced pre-extraction of coal seam gas mostly adopts gas injection to displace coal seam gas technology to improve the permeability of coal seams and achieve the purpose of enhanced extraction. The underground compressed air system makes it more convenient to obtain underground compressed air, but there is no systematic gas injection and extraction connection system at present. The existing gas injection pipeline connection method is mostly threaded connection, which has low pressure bearing, cumbersome connection, and is easy to cause gas leakage during the connection process, endangering the life safety of coal miners. Multi-parameter gas meter and gas meter are the most commonly used and most convenient gas gas metering tools at home and abroad, but the multi-parameter gas meter has problems such as inaccurate measurement, while the gas meter has accurate measurement and is often widely used in underground coal mine borehole gas flow measurement, but due to its structure, it is easily affected by moisture, coal powder and other substances, resulting in structural damage, and cannot be accurately measured. In view of the above problems, it is extremely necessary to invent a set of underground coal seam gas enhanced pre-extraction gas injection and connection system that can be used for water-containing boreholes, so as to realize the rapid connection of gas injection pipelines, and also reduce the resistance of the extraction system to achieve accurate measurement of gas flow. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a gas injection displacement flow-increasing gas extraction pipeline quick connection system and a gas injection method thereof, so as to overcome the problems of complex connection and replacement of gas injection pipelines during underground gas extraction, inaccurate extraction data monitoring, and easy damage of data monitoring equipment.

[0005] In order to solve the above technical problems, the present invention adopts the following technical scheme: a quick connection system for gas injection displacement flow-increasing gas extraction pipeline, comprising a gas injection device 3, a filtering device 4 and a gas metering device 5, the gas injection port of the gas injection device 3 is connected to the gas injection hole sealing pipe 33, the gas inlet of the gas injection device 3 is connected to the gas injection main pipe 1 under the coal mine, the gas inlet of the filtering device 4 is connected to the extraction hole sealing pipe 27 of the gas extraction system, the gas outlet of the filtering device 4 is connected to the gas inlet of the gas metering device 5, and the gas meter The gas outlet of the measuring device 5 is connected to the extraction main pipe 2 in the underground tunnel of the coal mine.

[0006] The filtering device 4 includes a filter 15, a sealed water tank 17, a water tank air inlet pipe 19 and a water tank air outlet pipe 20. The inlet of the filter 15 is connected to the outlet of the extraction hole sealing pipe 27 through a first adapter 13, and the inlet of the water tank air inlet pipe 19 is connected to the outlet of the filter 15 through a second adapter 14. An air release valve 16 is provided on the filter 15, and a water drain valve 18 is provided at the bottom of the sealed water tank 17.

[0007] The gas metering device 5 includes a multi-parameter gas meter 23, a first pipeline 40, a second pipeline 28 and a gas meter 26. The multi-parameter inlet end 22 of the multi-parameter gas meter 23 is connected to the water tank outlet pipe 20 through a thread, the multi-parameter outlet end 21 of the multi-parameter gas meter 23 is connected to one end of the first pipeline 40 through a thread, the gas inlet of the gas meter 26 is connected to the other end of the first pipeline 40 through a first reducer 24, and the gas outlet of the gas meter 26 is connected to the second reducer 47 through a second reducer 48. One end of the second pipeline 28 is connected, and the other end of the second pipeline 28 is connected to the extraction main pipe 2 through a first threaded buckle 29; a first valve 37 is arranged on the second pipeline 28, a second valve 38 is arranged on the water tank outlet pipe 20, and a third valve 39 is arranged on the extraction hole sealing pipe 27; the filtering device 4 and the gas metering device 5 are connected between the extraction hole sealing pipe 27 and the extraction main pipe 2, and then under the negative pressure of the extraction main pipe 2, the gas in the coal seam is extracted and filtered, water-gas separated and metered in turn to form an extraction circuit.

[0008] The gas injection device 3 includes a gas injection guide tube 12, a booster pump 8, a quick connector 6 and a third pipeline 25. The upper end of the quick connector 6 is connected to the gas injection hole sealing tube 33 through a telescopic buckle structure, and the lower end of the quick connector 6 is connected to one end of the third pipeline 25 through a thread. A brass ball valve 30 is provided at the lower end of the quick connector 6. A fixing ring 31, a quick-connect pressure gauge 32 and a quick-connect air release valve 36 are connected to the outer circle of the quick connector 6. The gas inlet end of the booster pump 8 is connected to one end of the gas injection guide tube 12, and the gas injection guide tube The other end of 12 is connected to the gas injection main pipe 1, and the gas outlet end of the booster pump 8 is connected to the other end of the third pipeline 25; the booster pump 8 is provided with a boost pressure gauge 9 and a boost valve 10; the third pipeline 25 is provided with a fourth valve 7, and the gas injection guide pipe 12 is provided with a valve switch 11; the gas injection device 3 is connected between the gas injection main pipe 1 and the gas injection hole sealing pipe 33, the booster pump 8 further pressurizes the positive pressure airflow in the gas injection main pipe 1 and injects it into the coal seam through the quick connector and the gas injection hole sealing pipe 33 to form a sealed loop.

[0009] The telescopic buckle structure includes a pressing cylinder 34 and two semicircular telescopic rings 35. The inner circle of the upper port of the quick connector 6 is provided with an annular step groove. Both ends of the two semicircular telescopic rings 35 are connected to form an annular shape by a radial tension spring 54. The two semicircular telescopic rings 35 are arranged on the annular step groove. A clamping block 48 is fixedly provided in the middle position of the inner circle of the two semicircular telescopic rings 35. The upper side and the lower side of the clamping block 48 are both cambered structures. The air inlet section of the air injection hole sealing tube 33 extends into the outer circle of the upper port of the quick connector 6 and is symmetrically provided with clamping grooves that are respectively buckled with the two clamping blocks 48. The pressing cylinder 34 is sleeved on the air injection hole sealing tube The outside of the tube 33 and the lower end thereof extend into the annular step groove, the outer circle of the lower end of the pressing cylinder 34 fits with the inner circle of the upper ends of the two semicircular telescopic rings 35, and the fitting surface is a conical structure that is thick at the top and thin at the bottom, and the upper end of the pressing cylinder 34 is integrally provided with an annular cap 49 whose outer diameter is larger than that of the pressing cylinder 34, and an axial tension spring 50 is provided between the lower surface of the annular cap 49 and the upper end ring surface of the quick connector 6, and a flexible protective sleeve 51 covering the axial tension spring 50 is provided between the lower end of the outer circle of the annular cap 49 and the upper end of the quick connector 6, and a rubber sealing ring 52 is provided on the inner circle of the upper port of the quick connector 6 below the annular step groove to seal with the outer circle of the gas injection hole sealing tube 33.

[0010] The gas injection method of the gas injection displacement flow-enhancing gas extraction pipeline quick connection system is carried out in the following steps:

[0011] Step 1: Close the first valve 37, the second valve 38 and the third valve 39 to ensure that there is no airflow in the pipeline; thread the inlet of the filter 15 to the extraction hole sealing pipe 27 through the first adapter 13, and connect the second pipeline 28 to the extraction main pipe 2 through the first thread 29;

[0012] Step 2: Open the drain valve 18 of the sealed water tank 17. If liquid flows out of the sealed water tank 17, wait until the water in the sealed water tank 17 is completely drained and close the drain valve 18. If no liquid flows out of the sealed water tank 17, the drain valve 18 can be directly closed.

[0013] Step 3: Slowly open the third valve 39, the second valve 38 and the first valve 37 in sequence. At this time, the gas in the extraction hole sealing tube 27 slowly flows through the filter 15, the sealed water tank 17, the multi-parameter gas meter 23, the gas meter 26 to the extraction main pipe 2 under the action of the extraction negative pressure in the extraction main pipe 2; if the gas contains coal powder or other solid impurities, the solid impurities in the gas will be removed when the gas flows through the filter 15, and the gas becomes a gas flow without solid impurities; if the gas contains water, when it flows through the sealed water tank 17, the water in the gas flow settles in the sealed water tank 17 due to gravity, and finally the gas without solid impurities and water enters the multi-parameter gas meter 23 and the gas meter 26, and enters the extraction main pipe 2 through the second pipeline 28;

[0014] Step 4: Observe the readings of the multi-parameter gas meter 23 and the gas meter 26. After the readings of both are stable, turn on the watch to record the initial time t1, the initial reading x1 of the gas meter 26, and the initial reading y1 of the multi-parameter gas meter 23. After a period of time, record the final time t2, the initial reading x2 of the gas meter 26, and the initial reading y2 of the multi-parameter gas meter 23; thus, the gas extraction volume m in the negative pressure pipeline can be calculated. 3 / min, that is

[0015] Step 5: Close the brass ball valve 30, the fourth valve 7 and the valve switch 11, connect the gas injection hole sealing tube 33 to the upper end of the quick connector 6, connect the gas injection guide tube 12 to the gas injection main pipe 1 through the second thread 53, and connect the fixing ring 31 to the nearby tunnel support frame through a cable tie to fix the quick connector 6 to avoid underground safety accidents caused by the quick connector 6 falling off due to excessive gas injection pressure;

[0016] Step 6: Slowly open the valve switch 11, the fourth valve 7 and the brass ball valve 30 in sequence, and the positive pressure gas in the gas injection main pipe 1 flows through the gas injection guide pipe 12 into the booster pump 8. Open the booster valve 10 of the booster pump 8. After the boosting effect of the booster pump 8, the high-pressure gas is injected into the gas injection hole sealing pipe 33 through the third pipeline 25 and the quick connector 6. After the reading of the quick-connect pressure gauge 32 on the quick connector 6 is stable, record the gas injection pressure p1;

[0017] Step 7: After the gas injection is completed, slowly close the valve switch 11, the fourth valve 7 and the brass ball valve 30 in sequence, open the quick-connect air release valve 36 to release the remaining gas in the gas injection connection pipeline, and when you put your finger on the air release port of the quick-connect air release valve 36 and feel a weak gas flow, close the quick-connect air release valve 36, then separate the gas injection hole sealing tube 33 from the quick connector 6, and quickly connect the gas injection hole sealing tube 33 to the extraction main pipe 2;

[0018] Step 8: Close the third valve 39, the second valve 38 and the first valve 37 in sequence, open the vent valve 16, and when no gas flows out, close the vent valve 16, separate the extraction hole sealing pipe 27 from the first adapter 13 of the filter 15, separate the second pipeline 28 from the extraction main pipe 2, and directly connect the extraction hole sealing pipe 27 to the extraction main pipe 2. At this time, the gas flows directly from the extraction hole sealing pipe 27 into the extraction main pipe 2.

[0019] Step 9: Open the drain valve 18 of the sealed water tank 17. If liquid flows out of the sealed water tank 17, wait until the water in the sealed water tank 17 is completely drained and close the drain valve 18. If no liquid flows out of the sealed water tank 17, close the drain valve 18 of the sealed water tank 17 for next time.

[0020] The specific process of connecting the gas injection hole sealing tube 33 with the upper port of the quick connector 6 in the fifth step is: first press the annular cap 49 to move the pressing cylinder 34 downward, and the diameter of the two semicircular telescopic rings 35 is driven to increase by the conical structure crimped between the pressing cylinder 34 and the two semicircular telescopic rings 35. The distance between the two clamping blocks 48 is increased to be equivalent to the inner diameter of the upper port of the quick connector 6, and the air inlet port of the gas injection hole sealing tube 33 is inserted into the upper port of the quick connector 6. When the gas injection hole sealing tube 33 can no longer be inserted, rotate the quick connector 6 or the gas injection hole sealing tube 33 so that the clamping block 48 at the middle position of the inner circle of the two semicircular telescopic rings 35 is clamped into the clamping groove of the outer circle of the gas injection hole sealing tube 33 under the action of two radial tension springs 54, and the gas injection hole sealing tube 33 is installed and connected to the quick connector 6 in place.

[0021] The specific process of separating the gas injection hole sealing tube 33 from the quick connector 6 in the eighth step is: pressing the annular cap 49 downwards, driving the pressing cylinder 34 to press the two semicircular telescopic rings 35 downwards. Since the outer circle of the lower end of the pressing cylinder 34 fits with the inner circle of the upper end of the two semicircular telescopic rings 35 and the fitting surface is a conical structure with a thick upper part and a thin lower part, the pressing cylinder 34 moves downwards, and the diameter of the two semicircular telescopic rings 35 is driven to increase through the conical structure, and the clamping block 48 is disengaged from the clamping slot, and the gas injection hole sealing tube 33 is pulled out of the upper port of the quick connector 6.

[0022] By adopting the above technical scheme, the present invention has outstanding substantial characteristics and significant progress compared with the prior art. Specifically, the present invention utilizes the quick connection and separation of the quick connector and the gas injection hole sealing tube to improve the speed and reliability of pipeline connection; in particular, the gas injection hole sealing tube is separated from the quick connector, thereby reducing the time for separating the gas injection sealing tube from the gas injection pipeline, thereby reducing the escape of residual gas in the tube into the working face, and protecting the lives of underground coal miners.

[0023] The present invention adopts a gas injection device to inject nitrogen, carbon dioxide and other safe gases into the coal seam, displaces the gas around the coal seam gas injection holes, drives the gas into the coal seam extraction holes, and extracts the gas by negative pressure suction, and then filters, separates water and gas, and measures the gas in sequence before collecting and extracting it through an extraction main pipe.

[0024] The present invention arranges a pre-filter and a sealed water tank at the front end of the multi-parameter gas meter and the gas meter, which solves the problem of equipment damage caused by impurities such as coal powder and condensed water in the pipeline entering the multi-parameter gas meter and the gas meter, and does not affect the resistance of the extraction system, thereby achieving the goal of increasing the accurate measurement of the gas flow.

[0025] The gas injection displacement pipeline and the gas extraction pipeline adopted in the present invention both adopt a quick-connect structure, which firstly ensures the sealing effect and greatly improves the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the present invention;

[0027] Figure 2 for Figure 1 Axial cross-sectional view of the quick connector;

[0028] Figure 3 yes Figure 2 Enlarged view of part A in the middle;

[0029] Figure 4 yes Figure 3 A top view of the two semicircular telescopic rings. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0031] like Figure 1-Figure 4As shown, the gas injection displacement flow enhancement gas extraction pipeline quick connection system of the present invention includes a gas injection device 3, a filter device 4 and a gas metering device 5, the gas injection port of the gas injection device 3 is connected to the gas injection hole sealing pipe 33, the gas inlet of the gas injection device 3 is connected to the gas injection main pipe 1 underground in the coal mine, the gas inlet of the filter device 4 is connected to the extraction hole sealing pipe 27 of the gas extraction system, the gas outlet of the filter device 4 is connected to the gas inlet of the gas metering device 5, and the gas outlet of the gas metering device 5 is connected to the extraction main pipe 2 in the underground tunnel of the coal mine. The gas injection hole sealing pipe 33 and the extraction hole sealing pipe 27 are both extended into the coal seam 55.

[0032] The filtering device 4 includes a filter 15, a sealed water tank 17, a water tank air inlet pipe 19 and a water tank air outlet pipe 20. The inlet of the filter 15 is connected to the outlet of the extraction hole sealing pipe 27 through a first adapter 13, and the inlet of the water tank air inlet pipe 19 is connected to the outlet of the filter 15 through a second adapter 14. An air release valve 16 is provided on the filter 15, and a water drain valve 18 is provided at the bottom of the sealed water tank 17.

[0033] The gas metering device 5 includes a multi-parameter gas meter 23, a first pipeline 40, a second pipeline 28 and a gas meter 26. The multi-parameter inlet end 22 of the multi-parameter gas meter 23 is connected to the water tank outlet pipe 20 through a thread, the multi-parameter outlet end 21 of the multi-parameter gas meter 23 is connected to one end of the first pipeline 40 through a thread, the gas inlet of the gas meter 26 is connected to the other end of the first pipeline 40 through a first reducer 24, and the gas outlet of the gas meter 26 is connected to the second reducer 47 through a second reducer 48. One end of the second pipeline 28 is connected, and the other end of the second pipeline 28 is connected to the extraction main pipe 2 through a first threaded buckle 29; a first valve 37 is arranged on the second pipeline 28, a second valve 38 is arranged on the water tank outlet pipe 20, and a third valve 39 is arranged on the extraction hole sealing pipe 27; the filtering device 4 and the gas metering device 5 are connected between the extraction hole sealing pipe 27 and the extraction main pipe 2, and then under the negative pressure of the extraction main pipe 2, the gas in the coal seam is extracted and filtered, water-gas separated and metered in turn to form an extraction circuit.

[0034] The gas injection device 3 includes a gas injection guide tube 12, a booster pump 8, a quick connector 6 and a third pipeline 25. The upper end of the quick connector 6 is connected to the gas injection hole sealing tube 33 through a telescopic buckle structure, and the lower end of the quick connector 6 is connected to one end of the third pipeline 25 through a thread. A brass ball valve 30 is provided at the lower end of the quick connector 6. A fixing ring 31, a quick-connect pressure gauge 32 and a quick-connect air release valve 36 are connected to the outer circle of the quick connector 6. The gas inlet end of the booster pump 8 is connected to one end of the gas injection guide tube 12, and the gas injection guide tube The other end of 12 is connected to the gas injection main pipe 1, and the gas outlet end of the booster pump 8 is connected to the other end of the third pipeline 25; the booster pump 8 is provided with a boost pressure gauge 9 and a boost valve 10; the third pipeline 25 is provided with a fourth valve 7, and the gas injection guide pipe 12 is provided with a valve switch 11; the gas injection device 3 is connected between the gas injection main pipe 1 and the gas injection hole sealing pipe 33, the booster pump 8 further pressurizes the positive pressure airflow in the gas injection main pipe 1 and injects it into the coal seam through the quick connector and the gas injection hole sealing pipe 33 to form a sealed loop.

[0035] The telescopic buckle structure includes a pressing cylinder 34 and two semicircular telescopic rings 35. The inner circle of the upper port of the quick connector 6 is provided with an annular step groove. Both ends of the two semicircular telescopic rings 35 are connected to form an annular shape by a radial tension spring 54. The two semicircular telescopic rings 35 are arranged on the annular step groove. A clamping block 48 is fixedly provided in the middle position of the inner circle of the two semicircular telescopic rings 35. The upper side and the lower side of the clamping block 48 are both cambered structures. The air inlet section of the air injection hole sealing tube 33 extends into the outer circle of the upper port of the quick connector 6 and is symmetrically provided with clamping grooves that are respectively buckled with the two clamping blocks 48. The pressing cylinder 34 is sleeved on the air injection hole sealing tube The outside of the tube 33 and the lower end thereof extend into the annular step groove, the outer circle of the lower end of the pressing cylinder 34 fits with the inner circle of the upper ends of the two semicircular telescopic rings 35, and the fitting surface is a conical structure that is thick at the top and thin at the bottom, and the upper end of the pressing cylinder 34 is integrally provided with an annular cap 49 whose outer diameter is larger than that of the pressing cylinder 34, and an axial tension spring 50 is provided between the lower surface of the annular cap 49 and the upper end ring surface of the quick connector 6, and a flexible protective sleeve 51 covering the axial tension spring 50 is provided between the lower end of the outer circle of the annular cap 49 and the upper end of the quick connector 6, and a rubber sealing ring 52 is provided on the inner circle of the upper port of the quick connector 6 below the annular step groove to seal with the outer circle of the gas injection hole sealing tube 33.

[0036] The gas injection method of the gas injection displacement flow-enhancing gas extraction pipeline quick connection system is carried out in the following steps:

[0037] Step 1: Close the first valve 37, the second valve 38 and the third valve 39 to ensure that there is no airflow in the pipeline; thread the inlet of the filter 15 to the extraction hole sealing pipe 27 through the first adapter 13, and connect the second pipeline 28 to the extraction main pipe 2 through the first thread 29;

[0038] Step 2: Open the drain valve 18 of the sealed water tank 17. If liquid flows out of the sealed water tank 17, wait until the water in the sealed water tank 17 is completely drained and close the drain valve 18. If no liquid flows out of the sealed water tank 17, the drain valve 18 can be directly closed.

[0039] Step 3: Slowly open the third valve 39, the second valve 38 and the first valve 37 in sequence. At this time, the gas in the extraction hole sealing tube 27 slowly flows through the filter 15, the sealed water tank 17, the multi-parameter gas meter 23, the gas meter 26 to the extraction main pipe 2 under the action of the extraction negative pressure in the extraction main pipe 2; if the gas contains coal powder or other solid impurities, the solid impurities in the gas will be removed when the gas flows through the filter 15, and the gas becomes a gas flow without solid impurities; if the gas contains water, when it flows through the sealed water tank 17, the water in the gas flow settles in the sealed water tank 17 due to gravity, and finally the gas without solid impurities and water enters the multi-parameter gas meter 23 and the gas meter 26, and enters the extraction main pipe 2 through the second pipeline 28;

[0040] Step 4: Observe the readings of the multi-parameter gas meter 23 and the gas meter 26. After the readings of both are stable, turn on the watch to record the initial time t1, the initial reading x1 of the gas meter 26, and the initial reading y1 of the multi-parameter gas meter 23. After a period of time, record the final time t2, the initial reading x2 of the gas meter 26, and the initial reading y2 of the multi-parameter gas meter 23; thus, the gas extraction volume m in the negative pressure pipeline can be calculated. 3 / min, that is

[0041] Step 5: Close the brass ball valve 30, the fourth valve 7 and the valve switch 11, connect the gas injection hole sealing tube 33 to the upper end of the quick connector 6, connect the gas injection guide tube 12 to the gas injection main pipe 1 through the second thread 53, and connect the fixing ring 31 to the nearby tunnel support frame through a cable tie to fix the quick connector 6 to avoid underground safety accidents caused by the quick connector 6 falling off due to excessive gas injection pressure;

[0042] Step 6: Slowly open the valve switch 11, the fourth valve 7 and the brass ball valve 30 in sequence, and the positive pressure gas in the gas injection main pipe 1 flows through the gas injection guide pipe 12 into the booster pump 8. Open the booster valve 10 of the booster pump 8. After the boosting effect of the booster pump 8, the high-pressure gas is injected into the gas injection hole sealing pipe 33 through the third pipeline 25 and the quick connector 6. After the reading of the quick-connect pressure gauge 32 on the quick connector 6 is stable, record the gas injection pressure p1;

[0043] Step 7: After the gas injection is completed, slowly close the valve switch 11, the fourth valve 7 and the brass ball valve 30 in sequence, open the quick-connect air release valve 36 to release the remaining gas in the gas injection connection pipeline, and when you put your finger on the air release port of the quick-connect air release valve 36 and feel a weak gas flow, close the quick-connect air release valve 36, then separate the gas injection hole sealing tube 33 from the quick connector 6, and quickly connect the gas injection hole sealing tube 33 to the extraction main pipe 2;

[0044] Step 8: Close the third valve 39, the second valve 38 and the first valve 37 in sequence, open the vent valve 16, and when no gas flows out, close the vent valve 16, separate the extraction hole sealing pipe 27 from the first adapter 13 of the filter 15, separate the second pipeline 28 from the extraction main pipe 2, and directly connect the extraction hole sealing pipe 27 to the extraction main pipe 2. At this time, the gas flows directly from the extraction hole sealing pipe 27 into the extraction main pipe 2.

[0045] Step 9: Open the drain valve 18 of the sealed water tank 17. If liquid flows out of the sealed water tank 17, wait until the water in the sealed water tank 17 is completely drained and close the drain valve 18. If no liquid flows out of the sealed water tank 17, close the drain valve 18 of the sealed water tank 17 for next time.

[0046] The specific process of connecting the gas injection hole sealing tube 33 with the upper port of the quick connector 6 in the fifth step is: first press the annular cap 49 to move the pressing cylinder 34 downward, and the diameter of the two semicircular telescopic rings 35 is driven to increase by the conical structure crimped between the pressing cylinder 34 and the two semicircular telescopic rings 35. The distance between the two clamping blocks 48 is increased to be equivalent to the inner diameter of the upper port of the quick connector 6, and the air inlet port of the gas injection hole sealing tube 33 is inserted into the upper port of the quick connector 6. When the gas injection hole sealing tube 33 can no longer be inserted, rotate the quick connector 6 or the gas injection hole sealing tube 33 so that the clamping block 48 at the middle position of the inner circle of the two semicircular telescopic rings 35 is clamped into the clamping groove of the outer circle of the gas injection hole sealing tube 33 under the action of two radial tension springs 54, and the gas injection hole sealing tube 33 is installed and connected to the quick connector 6 in place.

[0047] The specific process of separating the gas injection hole sealing tube 33 from the quick connector 6 in the eighth step is: pressing the annular cap 49 downwards, driving the pressing cylinder 34 to press the two semicircular telescopic rings 35 downwards. Since the outer circle of the lower end of the pressing cylinder 34 fits with the inner circle of the upper end of the two semicircular telescopic rings 35 and the fitting surface is a conical structure with a thick upper part and a thin lower part, the pressing cylinder 34 moves downwards, and the diameter of the two semicircular telescopic rings 35 is driven to increase through the conical structure, and the clamping block 48 is disengaged from the clamping slot, and the gas injection hole sealing tube 33 is pulled out of the upper port of the quick connector 6.

[0048] The above two embodiments do not impose any formal restrictions on the shape, material, structure, etc. of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Claims

1. Gas injection displacement flow enhancement gas extraction pipeline quick connection system, characterized by: The invention comprises an air injection device (3), a filtering device (4) and a gas metering device (5); the air injection port of the air injection device (3) is connected to an air injection hole sealing pipe (33); the air inlet of the air injection device (3) is connected to an air injection main pipe (1) in a coal mine; the air inlet of the filtering device (4) is connected to an extraction hole sealing pipe (27) of a gas extraction system; the air outlet of the filtering device (4) is connected to an air inlet of the gas metering device (5); and the air outlet of the gas metering device (5) is connected to an extraction main pipe (2) in a coal mine tunnel.

2. The gas injection displacement flow enhancement gas extraction pipeline quick connection system according to claim 1 is characterized in that: The filtering device (4) comprises a filter (15), a sealed water tank (17), a water tank air inlet pipe (19) and a water tank air outlet pipe (20); the inlet of the filter (15) is connected to the outlet of the extraction hole sealing pipe (27) via a first adapter (13); the inlet of the water tank air inlet pipe (19) is connected to the outlet of the filter (15) via a second adapter (14); an air release valve (16) is provided on the filter (15); and a water release valve (18) is provided at the bottom of the sealed water tank (17).

3. The gas injection displacement flow enhancement gas extraction pipeline quick connection system according to claim 2 is characterized by: The gas metering device (5) comprises a multi-parameter gas meter (23), a first pipeline (40), a second pipeline (28) and a gas meter (26); the multi-parameter inlet end (22) of the multi-parameter gas meter (23) is connected to the water tank gas outlet pipe (20) through a thread; the multi-parameter outlet end (21) of the multi-parameter gas meter (23) is connected to one end of the first pipeline (40) through a thread; the gas inlet of the gas meter (26) is connected to the other end of the first pipeline (40) through a first reducer (24); the gas outlet of the gas meter (26) is connected to the second reducer (47) through a second reducer (48). One end of the second pipeline (28) is connected, and the other end of the second pipeline (28) is connected to the extraction main pipe (2) through a first threaded buckle (29); a first valve (37) is provided on the second pipeline (28), a second valve (38) is provided on the water tank gas outlet pipe (20), and a third valve (39) is provided on the extraction hole sealing pipe (27); a filtering device (4) and a gas metering device (5) are connected between the extraction hole sealing pipe (27) and the extraction main pipe (2), and then under the negative pressure of the extraction main pipe (2), the gas in the coal seam is extracted and filtered, water-gas separated and metered in sequence to form an extraction circuit.

4. The gas injection displacement flow enhancement gas extraction pipeline quick connection system according to claim 3 is characterized by: The gas injection device (3) comprises a gas injection guide tube (12), a booster pump (8), a quick connector (6) and a third pipeline (25); the upper end of the quick connector (6) is connected to a gas injection hole sealing tube (33) via a telescopic buckle structure; the lower end of the quick connector (6) is connected to one end of the third pipeline (25) via a thread; a brass ball valve (30) is provided at the lower end of the quick connector (6); a fixing ring (31), a quick-connect pressure gauge (32) and a quick-connect air release valve (36) are connected to the outer circle of the quick connector (6); the gas inlet end of the booster pump (8) is connected to one end of the gas injection guide tube (12); the gas injection guide tube (12) is connected to one end of the gas injection hole sealing tube (33); the lower end of the quick connector (6 ... The other end of the gas injection main pipe (12) is connected to the gas injection main pipe (1), and the gas outlet end of the booster pump (8) is connected to the other end of the third pipe (25); the booster pump (8) is provided with a boost pressure gauge (9) and a boost valve (10); the third pipe (25) is provided with a fourth valve (7), and the gas injection flow guide pipe (12) is provided with a valve switch (11); the gas injection device (3) is connected between the gas injection main pipe (1) and the gas injection hole sealing pipe (33), and the booster pump (8) further pressurizes the positive pressure gas flow in the gas injection main pipe (1) and injects it into the coal seam through the quick connector and the gas injection hole sealing pipe (33) to form a sealed loop.

5. The gas injection displacement flow enhancement gas extraction pipeline quick connection system according to claim 4 is characterized in that: The telescopic buckle structure comprises a pressing cylinder (34) and two semicircular telescopic rings (35). The inner circle of the upper port of the quick connector (6) is provided with an annular step groove. Both ends of the two semicircular telescopic rings (35) are connected to form an annular shape by a radial tension spring (54). The two semicircular telescopic rings (35) are arranged on the annular step groove. A clamping block (48) is fixedly provided at the middle position of the inner circle of the two semicircular telescopic rings (35). The upper side and the lower side of the clamping block (48) are both arc surface structures. The outer circle of the air inlet section of the air injection hole sealing tube (33) extending into the upper port of the quick connector (6) is symmetrically provided with clamping grooves respectively buckled with the two clamping blocks (48). The pressing cylinder (34) is sleeved on the air injection hole sealing tube (33). 3) outside and the lower end extends into the annular step groove, the outer circle of the lower end of the pressing cylinder (34) fits with the inner circle of the upper end of the two semicircular telescopic rings (35), and the fitting surface is a conical structure with a thick upper part and a thin lower part. The upper end of the pressing cylinder (34) is integrally provided with an annular cap (49) whose outer diameter is larger than that of the pressing cylinder (34), an axial tension spring (50) is provided between the lower surface of the annular cap (49) and the upper end ring surface of the quick connector (6), a flexible protective sleeve (51) covering the axial tension spring (50) is provided between the lower end of the outer circle of the annular cap (49) and the upper end of the quick connector (6), and a rubber sealing ring (52) is provided on the inner circle of the upper port of the quick connector (6) below the annular step groove to seal with the outer circle of the gas injection hole sealing tube (33).

6. The gas injection method of the gas injection displacement flow-increasing gas extraction pipeline quick connection system according to claim 5 is characterized in that: Proceed as follows: Step 1: Close the first valve (37), the second valve (38) and the third valve (39) to ensure that no air flows through the pipeline; connect the inlet of the filter (15) to the extraction hole sealing pipe (27) through the first adapter (13), and connect the second pipeline (28) to the extraction main pipe (2) through the first thread (29); Step 2: Open the drain valve (18) of the sealed water tank (17). If liquid flows out of the sealed water tank (17), wait until the water in the sealed water tank (17) is completely drained and then close the drain valve (18). If no liquid flows out of the sealed water tank (17), directly close the drain valve (18). Step 3: Slowly open the third valve (39), the second valve (38) and the first valve (37) in sequence. At this time, the gas in the extraction hole sealing tube (27) slowly flows through the filter (15), the sealed water tank (17), the multi-parameter gas meter (23) and the gas meter (26) in sequence to the extraction main pipe (2) under the action of the extraction negative pressure in the extraction main pipe (2); if the gas contains coal powder or other solid impurities, the solid impurities in the gas will be removed when the gas flows through the filter (15), and the gas becomes a gas flow without solid impurities; if the gas contains water, when it flows through the sealed water tank (17), the water in the gas flow settles in the sealed water tank (17) due to the action of gravity, and finally the gas without solid impurities and water enters the multi-parameter gas meter (23) and the gas meter (26), and enters the extraction main pipe (2) through the second pipeline (28); Step 4: Observe the readings of the multi-parameter gas meter (23) and the gas meter (26). After the readings of the two are stable, turn on the watch to record the initial time t1, the initial reading x1 of the gas meter (26), and the initial reading y1 of the multi-parameter gas meter (23). After a period of time, record the final time t2, the initial reading x2 of the gas meter (26), and the initial reading y2 of the multi-parameter gas meter (23); thus, the gas extraction volume (m 3 / min), which is Step 5: Close the brass ball valve (30), the fourth valve (7) and the valve switch (11), connect the gas injection hole sealing tube (33) to the upper end of the quick connector (6), connect the gas injection flow guide tube (12) to the gas injection main pipe (1) through the second thread (53), connect the fixing ring (31) to the nearby tunnel support frame through a cable tie to fix the quick connector (6), and avoid underground safety accidents caused by the quick connector (6) falling off due to excessive gas injection pressure; Step 6: Slowly open the valve switch (11), the fourth valve (7) and the brass ball valve (30) in sequence, and the positive pressure gas in the gas injection main pipe (1) flows through the gas injection guide pipe (12) into the booster pump (8). The booster valve (10) of the booster pump (8) is opened. After the boosting effect of the booster pump (8), the high-pressure gas is injected into the gas injection hole sealing pipe (33) through the third pipeline (25) and the quick connector (6). After the reading of the quick-connect pressure gauge (32) on the quick connector (6) stabilizes, record the gas injection pressure p1; Step 7: After the gas injection is completed, slowly close the valve switch (11), the fourth valve (7) and the brass ball valve (30) in sequence, open the quick-connect air release valve (36) to release the remaining gas in the gas injection connection pipeline, and when you put your finger on the air release port of the quick-connect air release valve (36) and feel a weak gas flow, close the quick-connect air release valve (36), then separate the gas injection hole sealing tube (33) from the quick connector (6), and quickly connect the gas injection hole sealing tube (33) to the extraction main pipe (2); Step 8: Close the third valve (39), the second valve (38) and the first valve (37) in sequence, open the vent valve (16), and when no gas flows out, close the vent valve (16), separate the extraction hole sealing pipe (27) from the first adapter (13) of the filter (15), separate the second pipeline (28) from the extraction main pipe (2), and directly connect the extraction hole sealing pipe (27) to the extraction main pipe (2). At this time, the gas flows directly from the extraction hole sealing pipe (27) into the extraction main pipe (2). The ninth step: open the drain valve (18) of the sealed water tank (17); if liquid flows out of the sealed water tank (17), wait until the water in the sealed water tank (17) is completely drained, and then close the drain valve (18); if no liquid flows out of the sealed water tank (17), close the drain valve (18) of the sealed water tank (17) for next standby.

7. The gas injection method of the gas injection displacement flow-increasing gas extraction pipeline quick connection system according to claim 6, characterized in that: The specific process of connecting the gas injection hole sealing tube (33) with the upper port of the quick connector (6) in the fifth step is as follows: first, the annular cap (49) is pressed to move the pressing cylinder (34) downward, and the diameter of the two semicircular telescopic rings (35) is driven to increase through the conical structure of the pressing cylinder (34) and the two semicircular telescopic rings (35) pressed together, and the distance between the two clamping blocks (48) is increased to be equivalent to the inner diameter of the upper port of the quick connector (6), so that the gas injection hole is sealed. The air inlet port of the tube (33) is inserted into the upper port of the quick connector (6). When the air injection hole sealing tube (33) cannot be inserted any further, the quick connector (6) or the air injection hole sealing tube (33) is rotated so that the clamping block (48) at the middle position of the inner circle of the two semicircular telescopic rings (35) is clamped into the clamping groove of the outer circle of the air injection hole sealing tube (33) under the action of two radial tension springs (54). The air injection hole sealing tube (33) and the quick connector (6) are installed and connected in place.

8. The gas injection method of the gas injection displacement flow-increasing gas extraction pipeline quick connection system according to claim 6, characterized in that: The specific process of separating the gas injection hole sealing tube (33) from the quick connector (6) in the eighth step is as follows: the annular cap (49) is pressed downward to drive the pressing cylinder (34) to press the two semicircular telescopic rings (35) downward. Since the outer circle of the lower end of the pressing cylinder (34) fits with the inner circle of the upper end of the two semicircular telescopic rings (35) and the fitting surface is a conical structure with a thick upper part and a thin lower part, the pressing cylinder (34) moves downward, and the diameter of the two semicircular telescopic rings (35) is increased through the conical structure, and the clamping block (48) is disengaged from the clamping groove, and the gas injection hole sealing tube (33) is pulled out of the upper port of the quick connector (6).

Images