A gas extraction system and extraction method based on mathematical model

Abstract

The present invention discloses a gas extraction system and extraction method based on a mathematical model, which relates to the technical field of gas extraction, and comprises a main drill bit, a connecting piece and a drill rod which are coaxially connected in sequence, wherein the drill rod has a water inlet channel, the main drill bit has a flushing hole, and the connecting piece has a connecting hole connecting the flushing hole and the water inlet channel; an inner rod is also coaxially fixed in the water inlet channel, a sampling assembly is provided in the inner rod for limited sliding, an accommodating hole is provided in the middle of the main drill bit, so that the sampling assembly can slide through the connecting piece and the accommodating hole for sampling; the water inlet channel can also be used as an extraction channel; and a model building assembly is also included, which is used to receive samples from the sampling assembly and analyze and model them to form a mathematical model, and the mathematical model is used to guide the gas extraction system to extract gas.

Description

Technical Field

[0001] The present invention relates to the technical field of gas extraction, and in particular to a gas extraction system and extraction method based on a mathematical model. Background Art

[0002] A large amount of gas is generated during coal mining. If it is not extracted in time, it may cause safety accidents such as explosions and suffocation. The main principle of gas extraction technology is to drill holes in the coal (rock) layer and directly extract the gas in the coal seam, thereby reducing the gas content in the coal seam and the gas outflow in the mine, and reducing the occurrence of safety accidents. By analyzing the coal and rock samples and calculating and forming a mathematical model based on the analysis results, gas can be extracted more efficiently, the gas concentration in the mine can be reduced, and the occurrence of safety accidents such as gas explosions can be avoided. In this process, it is particularly important to obtain coal and rock samples during the extraction process and then analyze them and establish a mathematical model.

[0003] Therefore, it is necessary to provide a gas extraction system and extraction method based on a mathematical model to solve the problems raised in the above background technology. Summary of the invention

[0004] To achieve the above object, the present invention provides the following technical solution: a gas extraction system based on a mathematical model, comprising a main drill bit, a connecting piece, and a drill rod coaxially connected in sequence, wherein the drill rod has a water inlet channel, the main drill bit has a flushing hole, and the connecting piece has a connecting hole connecting the flushing hole and the water inlet channel;

[0005] An inner rod is coaxially fixed in the water inlet channel, a sampling assembly is provided in the inner rod for limited sliding, and a receiving hole is provided in the middle of the main drill bit so that the sampling assembly can slide through the connecting piece and the receiving hole for sampling;

[0006] The water inlet channel can also serve as a drainage channel;

[0007] It also includes a model building component, which is used to receive samples from the sampling component and analyze and model them to form a mathematical model. The mathematical model is used to guide the gas extraction system to perform gas extraction.

[0008] Further, as a preference, the sampling assembly comprises a sampling barrel, a square seat, a sampling drill bit and a blocking plate, wherein the inner rod has a square hole, a limit seal in the square hole is slidably connected to the square seat, a discharge hole is provided in the middle of the square seat, and the discharge hole is communicated with the sampling barrel;

[0009] The blocking plate is limitedly sealed and slidably arranged in the square hole. One side of the blocking plate is connected to the sampling drill bit by a connecting rod. The connecting rod can penetrate the sampling cylinder. When the blocking plate contacts the square seat, a feed channel is formed between the sampling drill bit and the sampling cylinder.

[0010] Furthermore, as a preference, a limiting block is also fixed in the inner rod, and the limiting block can limit the square seat, and when the square seat is in contact with the limiting block, the sampling drill bit can just extend out of the accommodating hole.

[0011] Further, as a preference, a first magnetic block is embedded in the square seat, and a second magnetic block is embedded in the sealing plate, and the first magnetic block and the second magnetic block are configured as follows: after the thrust on the sealing plate is removed, under the action of the first magnetic block and the second magnetic block, the sealing plate and the square seat can move away from each other, and the feed channel disappears, and when power fluid is injected into the inner rod, a thrust on the sealing plate can be generated.

[0012] Furthermore, preferably, a sealing ring is fixed to the outside of the sampling drill bit, and the sealing ring can be sealingly and slidably connected to the sampling tube.

[0013] Further, preferably, a crushing tooth is formed at one end of the sampling tube close to the sampling drill bit.

[0014] Further, as a preference, a first swivel joint is provided at the tail of the drill pipe, the first swivel joint is connected to a tee pipe, and the tee pipe is also connected to a liquid supply pipe and a pumping pipe, respectively.

[0015] Furthermore, preferably, an annular blocking bag is fixed to the outer peripheral side of the drill pipe, and the blocking bag is connected to the water inlet channel of the drill pipe through a blocking tube, and a solenoid valve is also arranged in the blocking tube.

[0016] A method for extraction comprises the following steps:

[0017] S1. The drilling power is provided to the main drill bit through the drill pipe. During the drilling process, the flushing fluid is injected through the water inlet channel. At the same time, the power fluid is injected into the inner rod and a certain pressure is maintained, thereby making use of the sampling assembly to be kept in the inner rod;

[0018] S2. After the main drill bit has drilled for a period of time, the supply of flushing fluid is stopped, and the power fluid pressure in the inner rod is increased, so that a feed channel is formed between the sampling drill bit and the sampling tube, and the sampling drill bit can extend out of the accommodating hole for sampling;

[0019] S3. Stop the supply of power fluid and inject flushing fluid through the water inlet channel, wherein part of the flushing fluid can pass through the receiving hole and push the sampling assembly away from the main drill bit so that the staff can collect the sample;

[0020] S4. Sending the sample to the model building component to analyze the sample and establish a mathematical model, and guiding the gas extraction system to perform gas extraction through the mathematical model;

[0021] S5. After using the drill pipe 1 to extract for a period of time, repeat S1-S4.

[0022] Compared with the prior art, the present invention provides a gas extraction system and extraction method based on a mathematical model, which has the following beneficial effects:

[0023] The gas extraction system in the embodiment of the present invention can realize drilling, sampling and gas extraction. After sampling, the sample can be analyzed using a model building component, and then the staff calculates the sample parameters to form a mathematical model, thereby guiding the gas extraction system to perform more reasonable gas extraction.

[0024] In the embodiment of the present invention, the position of the sampling assembly can be adjusted by using the power fluid and the flushing fluid, and the gap between the sealing plate and the square seat can be adjusted, so that a feed channel can be formed between the sampling drill bit and the sampling barrel. In addition, under the action of the first magnetic block and the second magnetic block, the sealing plate and the square seat can move away from each other, and the feed channel disappears. At this time, the sampling drill bit can seal the sampling barrel and reduce the impact of the subsequent flushing fluid on the rock sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a gas extraction system based on a mathematical model;

[0026] Figure 2 for Figure 1 A partially enlarged structural schematic diagram;

[0027] Figure 3 It is a schematic diagram of the structure of a sampling component in a gas extraction system based on a mathematical model;

[0028] In the figure: 1. drill rod; 2. connecting part; 3. main drill bit; 4. inner rod; 5. sampling assembly; 6. support member; 7. tee pipe; 8. model building assembly; 9. sealing bag; 10. solenoid valve; 11. limit block; 51. sampling tube; 52. square seat; 53. crushing tooth; 54. sampling drill bit; 55. sealing ring; 56. connecting rod; 57. sealing plate; 58. first magnetic block; 59. second magnetic block; 510. feed channel. DETAILED DESCRIPTION

[0029] Please refer to Figure 1-3 In an embodiment of the present invention, a gas extraction system based on a mathematical model is provided, comprising a main drill bit 3, a connecting piece 2, and a drill rod 1 which are coaxially connected in sequence, wherein the drill rod 1 has a water inlet channel, the main drill bit 3 has a flushing hole, and the connecting piece 2 has a connecting hole communicating the flushing hole and the water inlet channel;

[0030] During the process of the main drill bit 3 drilling and forming a borehole, the drill rod 1 provides the main drill bit 3 with rotational power and axial feed power, and can also inject flushing liquid into the water inlet channel, and the flushing liquid flows through the water inlet channel, the connecting hole, and the flushing hole and enters the annulus; the annulus refers to: the gap between the outer diameter of the drill rod and the inner diameter of the borehole;

[0031] The following effects can also be achieved by passing the flushing fluid:

[0032] 1. Flushing cuttings: Flushing fluid has flushing ability and can carry cuttings out of the hole;

[0033] 2. Lowering the temperature: A large amount of friction heat will be generated during the drilling process of the main drill bit 3. Passing in cooling flushing fluid can lower the temperature of the main drill bit 3 and the drill rod 1;

[0034] 3. Stabilize the hole wall: When the flushing liquid flows through the hole wall, it will form a uniform film, which plays a role in fixing the hole wall and preventing it from slipping.

[0035] An inner rod 4 is coaxially fixed in the water inlet channel, a sampling assembly 5 is provided in the inner rod 4 for limited sliding, and a receiving hole is provided in the middle of the main drill bit 3 so that the sampling assembly 5 can slide through the connecting piece 2 and the receiving hole for sampling;

[0036] The water inlet channel can also serve as a drainage channel;

[0037] It also includes a model building component 8, which is used to receive samples from the sampling component 5 and analyze and model them to form a mathematical model. The mathematical model is used to guide the gas extraction system to perform gas extraction.

[0038] The model building component 8 may include equipment such as a triaxial pressure test device, which is used to obtain parameters such as porosity, desorption and permeability, and then the staff can calculate and form a mathematical model based on the relevant parameters, which are all existing technologies and will not be repeated here;

[0039] In this embodiment, the sampling assembly 5 includes a sampling tube 51, a square seat 52, a sampling drill bit 54 and a blocking plate 57, wherein the inner rod 4 has a square hole, and the square hole is limited and sealed and slidably connected to the square seat 52.

[0040] The square seat 52 has a discharge hole in the middle, and the discharge hole is connected to the sampling tube 51;

[0041] The sealing plate 57 is slidably arranged in the square hole in a limited sealing manner. One side of the sealing plate 57 is connected to the sampling drill bit 54 by a connecting rod 56. The connecting rod 56 can penetrate the sampling tube 51, and when the sealing plate 57 contacts the square seat 52, a feed channel 510 is formed between the sampling drill bit 54 and the sampling tube 51.

[0042] That is to say, the shape of the square seat 52 corresponds to the shape of the square hole, and is so arranged that when the inner rod 4 rotates, the square seat 52 rotates accordingly, and the inner rod 4 is coaxially fixed in the water inlet channel, so when the drill rod 1 rotates, it can transmit power to the square seat 52. Specifically, the inner rod 4 is connected to the water inlet channel by a support member 6. It should be noted that the support member does not completely hinder the flow of the flushing liquid in the water inlet channel, that is, the flushing liquid can pass through the support member into the connecting hole and the flushing hole;

[0043] Similarly, the shape of the blocking plate 57 corresponds to the shape of the square hole, and is configured so that when the inner rod 4 rotates, the blocking plate 57 rotates accordingly, and the inner rod 4 is coaxially fixed in the water inlet channel, so that when the drill rod 1 rotates, power can be transmitted to the blocking plate 57, thereby causing the sampling drill bit 54 to rotate synchronously;

[0044] In addition, a first magnetic block 58 is embedded in the square seat 52, and a second magnetic block 59 is embedded in the sealing plate 57. The first magnetic block 58 and the second magnetic block 59 are configured as follows: after the thrust on the sealing plate 57 is removed, under the action of the first magnetic block 58 and the second magnetic block 59, the sealing plate 57 and the square seat 52 can move away from each other, and the feed channel 510 disappears, and when power fluid is injected into the inner rod 4, a thrust on the sealing plate 57 can be generated.

[0045] When sampling is performed using the sampling assembly 5, power fluid is injected into the inner rod 4 to form a thrust on the plugging plate 57. This thrust causes the plugging plate 57 to contact the square seat 52, thereby forming a feed channel 510 between the sampling drill bit 54 and the sampling barrel 51. In addition, this thrust can cause the sampling assembly 5 to move toward the main drill bit as a whole, thereby allowing the sampling drill bit 54 to just pass through the accommodating hole. In this case, when the drill rod 1 rotates, the sampling drill bit 54 rotates accordingly, thereby achieving rock breaking, and the rock cuttings enter the sampling barrel 51 through the feed channel 510;

[0046] When the thrust on the sealing plate 57 is removed, under the action of the first magnetic block 58 and the second magnetic block 59, the sealing plate 57 and the square seat 52 can move away from each other, and the feed channel 510 disappears. At this time, the sampling drill bit can seal the sampling tube 51, reducing the impact of subsequent flushing fluid on the rock sample. At this time, flushing fluid is filled into the drill rod 1, and the flushing fluid can enter the inner rod 4 from the accommodating hole, and push the sampling drill bit 54 and the square seat 52 toward the orifice position until the sampling assembly 5 is separated from the inner rod 4. During this process, the flushing fluid will not affect the debris in the sampling tube.

[0047] It should also be noted that the drill rod 1 can be formed by screwing multiple drill rod monomers, and the length of the drill rod can be gradually increased according to the drilling depth of the main drill bit. Similarly, the inner rod 4 can also be formed by screwing multiple inner rod monomers, which will not be repeated here.

[0048] As a preferred embodiment, a limiting block 11 is also fixed in the inner rod 4, and the limiting block 11 can limit the square seat 52, and when the square seat 52 is in contact with the limiting block 11, the sampling drill bit 54 can just extend out of the accommodating hole. Such a setting can also effectively prevent the sampling component 5 from separating from the inner rod 4 due to the position of the main drill bit 3.

[0049] As a preferred embodiment, a sealing ring 55 is fixed to the outside of the sampling drill bit 54, and the sealing ring 55 can be sealingly and slidably connected to the sampling tube 51. Such an arrangement can improve the sealing effect of the sampling drill bit 54 on the sampling tube.

[0050] As a preferred embodiment, a crushing tooth 53 is formed at one end of the sampling tube 51 close to the sampling drill bit 54 .

[0051] In this embodiment, a first swivel joint is provided at the tail of the drill pipe 1, and the first swivel joint is connected to a tee pipe 7, and the tee pipe 7 is also connected to a liquid supply pipe and a pumping pipe respectively;

[0052] A second rotatable structure is disposed inside the inner rod 4, and the second rotatable joint is connected to a power fluid pipe.

[0053] The liquid supply pipe is connected to the external flushing liquid supply equipment, the extraction pipe is connected to the external suction system, and the power liquid pipe is connected to the external power liquid supply equipment.

[0054] In this embodiment, an annular blocking bag 9 is fixed to the outer peripheral side of the drill rod 1. The blocking bag 9 is connected to the water inlet channel of the drill rod 1 through a blocking tube. A solenoid valve 10 is also provided in the blocking tube.

[0055] Before flushing the debris in the annulus with flushing liquid, the solenoid valve 10 is in a closed state, and the blocking bag 9 is in a shrunk state. When flushing the debris in the annulus with flushing liquid, the solenoid valve 10 continues to remain closed, so that the debris in the annulus can flow smoothly to the orifice and be collected;

[0056] When the flushing liquid is used to drive the sampling assembly 5 to move toward the orifice position, the solenoid valve can be opened to expand the blocking bag 9, thereby increasing the pressure of the flushing liquid entering the inner rod 4 and increasing the moving speed of the sampling assembly 5.

[0057] A method for extraction comprises the following steps:

[0058] S1. The main drill bit 3 is provided with drilling power through the drill rod 1. During the drilling process, flushing fluid is injected through the water inlet channel. At the same time, power fluid is injected into the inner rod 4 and a certain pressure is maintained, so that the sampling assembly 5 is kept in the inner rod 4 to prevent the flushing fluid from being discharged from the inner rod 4;

[0059] S2. After the main drill bit 3 has drilled for a period of time, the supply of flushing fluid is stopped, and the power fluid pressure in the inner rod 4 is increased, so that a feed channel 510 is formed between the sampling drill bit 54 and the sampling tube 51, and the sampling drill bit 54 can extend out of the accommodating hole for sampling;

[0060] S3. Stop the supply of power fluid. At this time, under the action of the first magnetic block 58 and the second magnetic block 59, the blocking plate 57 and the square seat 52 can move away from each other, and the feed channel 510 disappears. At this time, the sampling drill bit can block the sampling tube 51, reducing the impact of subsequent flushing fluid on the rock sample.

[0061] A flushing liquid is injected through the water inlet channel, wherein part of the flushing liquid can pass through the receiving hole and push the sampling assembly away from the main drill bit 3, so that the staff can collect the sample;

[0062] S4. Sending the sample to the model building component 8 to analyze the sample and establish a mathematical model, and guiding the gas extraction system to perform gas extraction through the mathematical model;

[0063] S5. After using the drill pipe 1 to extract for a period of time, repeat S1-S4.

[0064] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A gas extraction system based on a mathematical model, characterized in that: It comprises a main drill bit (3), a connecting piece (2), and a drill rod (1) which are coaxially connected in sequence, wherein the drill rod (1) has a water inlet channel, the main drill bit (3) has a flushing hole, and the connecting piece (2) has a connecting hole connecting the flushing hole and the water inlet channel; An inner rod (4) is coaxially fixed in the water inlet channel, a sampling assembly (5) is provided in the inner rod (4) for limited sliding, and a receiving hole is provided in the middle of the main drill bit (3) so that the sampling assembly (5) can slide through the connecting piece (2) and the receiving hole to perform sampling; The water inlet channel can also serve as a drainage channel; It also includes a model building component (8) for receiving samples from the sampling component (5) and analyzing and modeling the samples to form a mathematical model, wherein the mathematical model is used to guide the gas extraction system to perform gas extraction; The sampling assembly (5) comprises a sampling tube (51), a square seat (52), a sampling drill bit (54) and a blocking plate (57), wherein the inner rod (4) has a square hole, a position-limiting seal in the square hole is slidably connected to the square seat (52), and a discharge hole is provided in the middle of the square seat (52), and the discharge hole is communicated with the sampling tube (51); The blocking plate (57) is slidably disposed in the square hole in a limited sealing manner. One side of the blocking plate (57) is connected to the sampling drill bit (54) by a connecting rod (56). The connecting rod (56) can penetrate the sampling barrel (51). When the blocking plate (57) contacts the square seat (52), a feed channel (510) is formed between the sampling drill bit (54) and the sampling barrel (51). A first magnetic block (58) is embedded in the square seat (52), and a second magnetic block (59) is embedded in the sealing plate (57). The first magnetic block (58) and the second magnetic block (59) are configured as follows: when the thrust on the sealing plate (57) is removed, under the action of the first magnetic block (58) and the second magnetic block (59), the sealing plate (57) and the square seat (52) can move away from each other and make the feed channel (510) disappear, and when power fluid is injected into the inner rod (4), a thrust on the sealing plate (57) can be generated.

2. A gas extraction system based on a mathematical model according to claim 1, characterized in that: A limiting block (11) is also fixed in the inner rod (4), and the limiting block (11) can limit the square seat (52), and when the square seat (52) is in contact with the limiting block (11), the sampling drill bit (54) can just extend out of the accommodating hole.

3. A gas extraction system based on a mathematical model according to claim 1, characterized in that: A sealing ring (55) is also fixed to the outside of the sampling drill bit (54), and the sealing ring (55) can be connected to the sampling tube (51) in a sealing and sliding manner.

4. A gas extraction system based on a mathematical model according to claim 1, characterized in that: A crushing tooth (53) is formed on one end of the sampling tube (51) close to the sampling drill bit (54).

5. A gas extraction system based on a mathematical model according to claim 1, characterized in that: The tail of the drill rod (1) is provided with a first swivel joint, the first swivel joint is connected to a tee pipe (7), and the tee pipe (7) is also connected to a liquid supply pipe and a pumping pipe respectively.

6. A gas extraction system based on a mathematical model according to claim 1, characterized in that: An annular blocking bag (9) is also fixed on the outer peripheral side of the drill rod (1); the blocking bag (9) is connected to the water inlet channel of the drill rod (1) via a blocking pipe; and a solenoid valve (10) is also provided in the blocking pipe.

7. A gas extraction method, which uses the gas extraction system based on the mathematical model as claimed in any one of claims 1 to 6, characterized in that: The steps include: S1. The main drill bit (3) is provided with drilling power through the drill rod (1). During the drilling process, flushing fluid is injected through the water inlet channel. At the same time, power fluid is injected into the inner rod (4) and a certain pressure is maintained, thereby making the sampling assembly (5) remain in the inner rod (4); S2. After the main drill bit (3) has drilled for a period of time, the supply of flushing fluid is stopped, and the power fluid pressure in the inner rod (4) is increased, so that a feed channel (510) is formed between the sampling drill bit (54) and the sampling tube (51), and the sampling drill bit (54) can extend out of the receiving hole for sampling; S3. Stop the supply of power fluid and inject flushing fluid through the water inlet channel, wherein part of the flushing fluid can pass through the receiving hole and push the sampling assembly away from the main drill bit (3) so that the staff can collect the sample; S4. Sending the sample to the model building component (8) to analyze the sample and establish a mathematical model, and guiding the gas extraction system to perform gas extraction through the mathematical model; S5. After a period of extraction using the drill pipe (1), repeat S1-S4.

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