Directional long drill hole receiving and pumping method and device
By adding a full-hole section extraction pipe and a pressurized extraction system in the directional long drilling hole, the negative pressure along the path loss problem is solved, and efficient gas extraction of each section of the drilling hole is achieved, especially in the case of collapsed holes.
Patent Information
- Application Number
- CN202510646021.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-20
- Publication Date
- 2025-07-18
AI Technical Summary
The prior art cannot effectively reduce the negative pressure along the path of the directional long drilling hole, resulting in low extraction efficiency in the drilling hole, especially when the collapse hole in the middle of the drilling hole is blocked.
By adding a full-hole section extraction pipe in the drilling hole, the negative pressure loss is reduced by using the air-permeable smooth pipe wall, and a extraction port and a pressurized extraction system are set up in the depth of the drilling hole to form a high negative pressure zone to achieve synchronous extraction and prevent clogging.
Effective extraction of each hole section of the drilling hole is achieved, especially when the hole collapses in the middle of the hole, the efficient extraction of deep gas can be maintained. The steps are simple and the implementation is convenient.
Smart Images
Figure CN120331857A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of coal seam gas drainage, and specifically relates to a method and device for connecting and draining a directional long borehole. Background Technique
[0002] Gas is an important disaster-causing hidden gas during coal mining. At present, the gas stored in the coal seam of the working face is generally continuously drained by constructing boreholes to achieve the effect of increasing permeability and eliminating outbursts.
[0003] Borehole gas drainage mainly forms a negative pressure in the borehole of the gas drainage borehole, and uses the pressure difference between the negative pressure and the gas storage pressure to extract the gas from the coal seam to achieve the purpose of reducing the gas content in the coal seam. The length of an ordinary borehole is generally about 100m, and the negative pressure at the borehole orifice for gas drainage is generally about 30kpa. In recent years, with the application and popularization of directional boreholes in coal mines, the borehole length has reached more than 300m. Due to the increase in borehole length and the influence of borehole wall cracks and irregular borehole walls, a large amount of negative pressure loss along the way often occurs. In particular, the negative pressure at the bottom of the directional borehole often cannot meet the requirements of effective drainage negative pressure, resulting in low drainage efficiency.
[0004] The existing connection and drainage method through the sealing pipe at the borehole orifice cannot achieve the effective drainage effect on the entire hole section of the directional long borehole; based on this, there is an urgent need for a method and device for connecting and draining a directional long borehole to slow down the negative pressure loss along the way, achieve the effective drainage of gas in the deep section of the long borehole, improve the drainage efficiency, and have simple steps and be easy to implement. Summary of the Invention
[0005] The present invention aims at the above problems, makes up for the deficiencies of the existing technology, and provides a method and device for connecting and draining a directional long borehole; by adding a full-hole-section drainage pipe in the existing drainage pipe, the present invention reduces the loss of negative pressure along the borehole wall, can achieve the effective drainage effect on each hole section of the borehole, and can realize the effective drainage of the deep part of the borehole in the case of collapse and blockage in the middle of the borehole. The steps are simple and easy to implement.
[0006] To achieve the above object, the present invention adopts the following technical solutions.
[0007] The first directional long borehole connection and drainage method provided by the present invention includes the following steps;
[0008] Step 1: According to the borehole diameter, depth, orifice negative pressure, and the properties of the coal seam, sealing pipe, and drainage pipe, use theoretical calculation, numerical simulation, or on-site measurement methods to obtain the attenuation of the negative pressure with the increase of the borehole depth, master the pressure drop gradient along the borehole, reasonably select the size of the deep drainage pipe, and determine the value of the depth H of the long borehole to be sent in;
[0009] Step 2: After the long borehole is constructed in the coal body, in accordance with the general requirements of the existing borehole sealing length, one end of the sealing pipe is sent into the orifice section of the long borehole, and the deep drainage port of the deep drainage pipe is sent to the position of the borehole depth H of the long borehole;
[0010] Step 3: According to the existing borehole sealing method, seal the long borehole with the sealing material; connect the sealing pipe to the other end of the deep drainage pipe and the drainage confluence pipe respectively. Since the negative pressure loss along the airtight smooth pipe wall is small, through the high negative pressure in the drainage confluence pipe, high negative pressure zones are respectively formed at the inner port of the sealing pipe hole and the deep drainage port of the deep drainage pipe, realizing the synchronous high negative pressure drainage of the shallow section and the deep section of the long borehole.
[0011] As a preferred embodiment of the present invention, Step 3 further includes: connecting the other end of the deep drainage pipe to a connector, the other end of the connector passes through the sealing pipe and is connected to a booster drainage pipe, the connector is hermetically connected to the wall of the sealing pipe, and the other end of the booster drainage pipe is connected to a booster drainage pump; through the high negative pressure in the drainage confluence pipe, a high negative pressure zone is formed at the inner port of the sealing pipe hole, and through the increased negative pressure in the booster drainage pipe, and since the negative pressure loss along the airtight smooth pipe wall is small, a high negative pressure zone is formed at the deep drainage port of the deep drainage pipe, realizing the synchronous high negative pressure drainage of the shallow section and the deep section of the long borehole.
[0012] As another preferred embodiment of the present invention, the deep drainage pipe passes through the sealing pipe.
[0013] As another preferred embodiment of the present invention, the formula used in the theoretical calculation is a deformation of Darcy's formula: where Δp f is the pressure loss along the way, f is the friction coefficient, L is the length, D is the inner diameter, ρ is the gas density, and v is the gas flow rate.
[0014] As another preferred embodiment of the present invention, to prevent the deep drainage port from being blocked by coal slag in the hole during the process of pushing the deep drainage pipe towards the bottom of the hole, a deep drainage side port is opened on the pipe wall of the deep drainage pipe adjacent to the deep drainage port, for realizing the internal and external conduction of the deep drainage pipe.
[0015] The present invention also provides a second directional long borehole connection and drainage method, including the following steps;
[0016] Step 1: According to the borehole diameter, hole depth, orifice negative pressure, and the properties of the coal body, sealing pipe, and gas drainage pipe, use theoretical calculation, numerical simulation, or on-site measurement methods to obtain the attenuation of the negative pressure with the increase of the borehole depth, master the pressure drop gradient along the borehole, reasonably select the size of the deep gas drainage pipe, determine the depth H value of the long borehole to be sent, determine the number n, position K, and size R of the middle gas drainage ports on the deep gas drainage pipe, and form a high negative pressure drainage area synchronously in the middle and deep areas of the borehole through the middle gas drainage ports, so as to achieve the synchronous and efficient drainage effect of the middle and deep parts of the borehole;
[0017] Step 2: After the long borehole is constructed in the coal body, according to the general requirements of the existing sealing length, send one end of the sealing pipe to the orifice section of the long borehole, and send the deep gas drainage port of the deep gas drainage pipe to the position of the borehole depth H of the long borehole;
[0018] Step 3: According to the existing sealing method, complete the sealing of the long borehole through the sealing material; connect the sealing pipe to the other ends of the deep gas drainage pipe and the gas drainage manifold respectively. Since the negative pressure loss along the airtight and smooth pipe wall is small, high negative pressure areas are formed at the inner port of the hole of the sealing pipe and the deep gas drainage port of the deep gas drainage pipe respectively through the high negative pressure in the gas drainage manifold, realizing the synchronous high negative pressure drainage of the shallow and deep sections of the long borehole.
[0019] As a preferred embodiment of the present invention, the deep gas drainage pipe passes through the sealing pipe; an anti-blocking screen pipe is fixed outside the deep gas drainage pipe at the position where the middle gas drainage port is opened, and is sent into the long borehole synchronously with the deep gas drainage pipe to prevent the middle gas drainage port from being blocked due to borehole collapse and deformation.
[0020] In addition, the present invention also provides a directional long borehole gas connection device for implementing the above two directional long borehole gas connection methods. The device includes a sealing pipe, a deep gas drainage pipe, a deep gas drainage port, a middle gas drainage port, a deep gas drainage side port, an anti-blocking screen pipe, a connector, a booster gas drainage pipe, and a booster gas drainage pump; wherein, the deep gas drainage port is the port of the deep gas drainage pipe placed in the deep part of the borehole, the deep gas drainage side port is the opening on the pipe wall of the deep gas drainage pipe adjacent to the deep gas drainage port, the deep gas drainage pipe passes through the sealing pipe, the middle gas drainage port is a through hole opened on the outer wall of the middle part of the deep gas drainage pipe, the other end of the deep gas drainage pipe is connected to the booster gas drainage pipe through a connector, the other end of the booster gas drainage pipe is connected to the booster gas drainage pump, one end of the connector is located inside the sealing pipe, and the other end passes through the pipe wall of the sealing pipe. The outer wall of the connector is hermetically connected to the pipe wall of the sealing pipe, and an anti-blocking screen pipe is fixed outside the deep gas drainage pipe at the position where the middle gas drainage port is opened.
[0021] Advantages of the present invention:
[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: A directional long borehole connection and extraction method and device provided by the present invention reduce the loss of negative pressure along the hole wall by adding a full-hole-section extraction pipe inside the existing extraction pipe, enabling effective extraction of each hole section of the borehole. Moreover, when a cave-in and blockage occur in the middle of the borehole, effective extraction of the deep part of the borehole can be achieved. The steps are simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for description in the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0024] Figure 1 It is one of the implementation structure diagrams of the first directional long borehole connection and extraction method provided by the present invention.
[0025] Figure 2 It is the second implementation structure diagram of the first directional long borehole connection and extraction method provided by the present invention.
[0026] Figure 3 It is one of the implementation structure diagrams of the second directional long borehole connection and extraction method provided by the present invention.
[0027] Figure 4 It is the second implementation structure diagram of the second directional long borehole connection and extraction method provided by the present invention.
[0028] Figure 5 is Figure 4 a partial enlarged view of the middle extraction port and the anti-blocking screen pipe in
[0029] Reference numerals in the figures: 1 is a long borehole, 2 is a sealing pipe, 3 is a sealing material, 4 is a deep extraction pipe, 5 is a deep extraction port, 6 is a middle extraction port, 7 is an extraction confluence pipe, 8 is a swivel joint, 9 is a pressurized extraction pipe, 10 is a pressurized extraction pump, 51 is a deep extraction side port, and 61 is an anti-blocking screen pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0030] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the following further details the present invention in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0031] As Figure 1 and Figure 2 shown, a directional long borehole connection and extraction method provided by an embodiment of the present invention includes the following steps;
[0032] Step 1: According to the borehole diameter, hole depth, orifice negative pressure, and the properties of the coal body, sealing pipe 2, and gas drainage pipe, use theoretical calculation, numerical simulation, or on-site measurement to obtain the attenuation of negative pressure with the increase of borehole depth, master the pressure drop gradient along the borehole, reasonably select the size of the deep gas drainage pipe 4, and determine the hole depth H value of the long borehole 1; to ensure efficient negative pressure distribution throughout the borehole and improve the gas drainage efficiency. Preferably, ensure that the negative pressure inside the hole is higher than 13 kPa throughout the process.
[0033] Step 2: After the long borehole 1 is constructed in the coal body, according to the general requirements of the existing sealing length, send one end of the sealing pipe 2 into the orifice section of the long borehole 1. This orifice section is preferably the section less than 30 m from the orifice; send the deep gas drainage port 5 of the deep gas drainage pipe 4 to the hole depth H position of the long borehole 1. This hole depth H position is preferably more than 70 m from the orifice.
[0034] Step 3: According to the existing sealing method, complete the sealing of the long borehole 1 through the sealing material 3; connect the sealing pipe 2 to the other end of the deep gas drainage pipe 4 and the gas drainage manifold pipe 7 respectively. Since the negative pressure loss along the airtight smooth pipe wall is small, through the high negative pressure in the gas drainage manifold pipe 7, high negative pressure zones are formed at the inner port of the hole of the sealing pipe 2 and the deep gas drainage port 5 of the deep gas drainage pipe 4 respectively, realizing synchronous high negative pressure gas drainage for the shallow and deep sections of the long borehole 1.
[0035] Among them, Step 3 further includes: connecting the other end of the deep gas drainage pipe 4 to the adapter 8, and the other end of the adapter 8 passes through the sealing pipe 2 and is connected to the booster gas drainage pipe 9. The adapter 8 is hermetically connected to the wall of the sealing pipe 2, and the other end of the booster gas drainage pipe 9 is connected to the booster gas drainage pump 10; through the high negative pressure in the gas drainage manifold pipe 7, a high negative pressure zone is formed at the inner port of the hole of the sealing pipe 2, and through the increased negative pressure in the booster gas drainage pipe 9, and since the negative pressure loss along the airtight smooth pipe wall is small, a high negative pressure zone is formed at the deep gas drainage port 5 of the deep gas drainage pipe 4, realizing synchronous high negative pressure gas drainage for the shallow and deep sections of the long borehole 1.
[0036] Among them, both the sealing pipe 2 and the deep gas drainage pipe 4 are hollow airtight pipes; preferably, the deep gas drainage pipe 4 passes through the sealing pipe 2.
[0037] Preferably, the formula used in the theoretical calculation is a deformation of Darcy's formula: Where △pf is the frictional pressure loss, f is the friction coefficient, L is the length, D is the inner diameter, ρ is the gas density, and v is the gas velocity; local pressure loss should be considered Where △p j is the local pressure loss, ξ is the local resistance coefficient, which is related to factors such as material properties and dimensions.
[0038] Preferably, in order to prevent the deep drainage pipe 4 from being blocked by coal slag in the hole during the process of pushing it towards the bottom of the hole, a deep drainage side port 51 is provided on the pipe wall of the deep drainage pipe 4 adjacent to the deep drainage port 5 to achieve the internal and external conduction of the deep drainage pipe 4.
[0039] As Figures 3 to 5 shown, the directional long borehole gas drainage connection method provided by the embodiment of the present invention includes the following steps;
[0040] Step 1: According to the borehole diameter, hole depth, hole mouth negative pressure, and the properties of the coal body, the sealing pipe 2, and the deep drainage pipe 4, by means of theoretical calculation, numerical simulation, or on-site measurement, obtain the attenuation of the negative pressure with the increase of the borehole depth, master the pressure drop gradient of the negative pressure along the borehole, reasonably select the size of the deep drainage pipe 4, determine the value of the hole depth H of the long borehole 1 to be sent in, determine the number n, position K, and size R of the middle drainage ports 6 opened on the deep drainage pipe 4, and synchronously form a high negative pressure drainage area in the middle and deep areas of the borehole through the middle drainage ports 6 to achieve the synchronous and efficient drainage effect on the middle and deep parts of the borehole; to ensure the efficient drainage negative pressure distribution throughout the borehole and improve the drainage efficiency. Preferably, ensure that the negative pressure in the hole is higher than 13 kPa throughout the process.
[0041] Step 2: After the long borehole 1 is constructed in the coal body, according to the general requirements of the existing sealing length, send one end of the sealing pipe 2 into the hole mouth section of the long borehole 1, and this hole mouth section is preferably the section less than 30 m away from the hole mouth; send the deep drainage port of the deep drainage pipe 4 to the hole depth H position of the long borehole, and this hole depth H position is preferably more than 70 m away from the hole mouth;
[0042] Step 3: According to the existing sealing method, complete the sealing of the long borehole 1 through the sealing material 3; connect the sealing pipe 2 to the other end of the deep drainage pipe 4 and the drainage confluence pipe 7 respectively. Since the loss of the negative pressure along the airtight and smooth pipe wall is small, through the high negative pressure in the drainage confluence pipe 7, high negative pressure areas are respectively formed at the inner port of the hole of the sealing pipe 2 and the deep drainage port 5 of the deep drainage pipe 4 to achieve the synchronous high negative pressure drainage of the shallow and deep sections of the long borehole 1.
[0043] Preferably, the deep drainage pipe 4 passes through the sealing pipe 2; an anti-blocking screen pipe 61 is fixed outside the deep drainage pipe 4 at the position where the middle drainage port 5 is opened and is sent into the long borehole 1 synchronously with the deep drainage pipe 4 to prevent the middle drainage port 5 from being blocked due to the collapse and deformation of the borehole.
[0044] In addition, an embodiment of the present invention further provides a directional long borehole connection and extraction device for implementing the above two directional long borehole connection and extraction methods. The device includes a sealing pipe 2, a deep extraction pipe 4, a deep extraction port 5, a middle extraction port 6, a deep extraction side port 51, an anti-blocking screen pipe 6, a connector 8, a pressurized extraction pipe 9, and a pressurized extraction pump 10. Among them, the deep extraction port 5 is the port where the deep extraction pipe 4 is lowered to the deep part of the borehole, the deep extraction side port 51 is an opening on the pipe wall of the deep extraction pipe 4 adjacent to the deep extraction port 5, the deep extraction pipe 4 passes through the sealing pipe 2, the middle extraction port 6 is a through hole opened on the outer wall of the middle part of the deep extraction pipe 4, the other end of the deep extraction pipe 4 is connected to the pressurized extraction pipe 9 through the connector 8, the other end of the pressurized extraction pipe 9 is connected to the pressurized extraction pump 10, one end of the connector 8 is located inside the sealing pipe 2, and the other end passes out along the pipe wall of the sealing pipe 2. The outer wall of the connector 8 is hermetically connected to the pipe wall of the sealing pipe 2. An anti-blocking screen pipe 6 is fixed outside the deep extraction pipe 4 at the position where the middle extraction port 6 is opened.
[0045] It can be understood that the above specific description of the present invention is only for explaining the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced to achieve the same technical effects; as long as it meets the usage requirements, it is within the protection scope of the present invention.
Claims
1. A method for connecting and extracting by directional long drilling, characterized in that: It includes the following steps; Step 1: According to the borehole diameter, hole depth, hole mouth negative pressure, and the properties of the coal body, sealing pipe, and extraction pipe, use theoretical calculation, numerical simulation, or on-site measurement methods to obtain the attenuation of the negative pressure with the increase of the borehole depth, master the pressure drop gradient along the borehole, reasonably select the size of the deep extraction pipe, determine the value of the depth H of the long borehole to be sent in, and determine the number n, position K, and size R of the middle extraction ports on the deep extraction pipe. Through the middle extraction ports, high negative pressure extraction areas are simultaneously formed in the middle and deep areas of the borehole to achieve the synchronous and efficient extraction effect of the middle and deep parts of the borehole; Step 2: After the long borehole is constructed in the coal body, according to the general requirements of the existing sealing length, send one end of the sealing pipe into the hole mouth section of the long borehole, and send the deep extraction port of the deep extraction pipe to the position of the depth H of the long borehole; Step 3: According to the existing sealing method, complete the sealing of the long borehole with the sealing material; connect the sealing pipe to the other end of the deep extraction pipe and the extraction manifold respectively. Since the loss of negative pressure along the airtight and smooth pipe wall is small, through the high negative pressure in the extraction manifold, high negative pressure areas are respectively formed at the inner port of the hole of the sealing pipe and the deep extraction port of the deep extraction pipe, realizing the synchronous high negative pressure extraction of the shallow and deep sections of the long borehole.
2. The directional long borehole connection and extraction method according to claim 1, characterized in that: The said Step 3 also includes: Connect the other end of the deep extraction pipe to the adapter, and the other end of the adapter passes through the sealing pipe and is connected to the booster extraction pipe. The adapter is hermetically connected to the pipe wall of the sealing pipe, and the other end of the booster extraction pipe is connected to the booster extraction pump; through the high negative pressure in the extraction manifold, a high negative pressure area is formed at the inner port of the hole of the sealing pipe, and through the increased negative pressure in the booster extraction pipe, and since the loss of negative pressure along the airtight and smooth pipe wall is small, a high negative pressure area is formed at the deep extraction port of the deep extraction pipe, realizing the synchronous high negative pressure extraction of the shallow and deep sections of the long borehole.
3. The directional long borehole connection and extraction method according to claim 1, characterized in that: The said deep extraction pipe passes through the sealing pipe.
4. A directional long borehole connection and extraction method according to claim 1, characterized in that: The formula used in the theoretical calculation is a deformation of the Darcy formula: where △pf is the pressure loss along the way, f is the friction coefficient, L is the length, D is the inner diameter, ρ is the gas density, and v is the gas flow rate.
5. A directional long borehole connection and extraction method according to claim 1, characterized in that: To prevent the blockage of the deep extraction port caused by the coal slag in the hole during the process of pushing the deep extraction pipe towards the bottom of the hole, a deep extraction side port is opened on the pipe wall of the deep extraction pipe adjacent to the deep extraction port to realize the internal and external conduction of the deep extraction pipe.
6. A method for connecting and extracting by directional long drilling, characterized in that: It includes the following steps; Step 1: According to the borehole diameter, hole depth, hole mouth negative pressure, and the properties of the coal body, sealing pipe, and extraction pipe, use theoretical calculation, numerical simulation, or on-site measurement methods to obtain the attenuation of the negative pressure with the increase of the borehole depth, master the pressure drop gradient along the borehole, reasonably select the size of the deep extraction pipe, determine the value of the depth H of the long borehole to be sent in, and determine the number n, position K, and size R of the middle extraction ports on the deep extraction pipe. Through the middle extraction ports, high negative pressure extraction areas are simultaneously formed in the middle and deep areas of the borehole to achieve the synchronous and efficient extraction effect of the middle and deep parts of the borehole; Step 2: After the long borehole is constructed in the coal body, according to the general requirements of the existing sealing length, send one end of the sealing pipe into the hole mouth section of the long borehole, and send the deep extraction port of the deep extraction pipe to the position of the depth H of the long borehole; Step 3: According to the existing sealing method, complete the sealing of the long borehole with the sealing material; connect the sealing pipe to the other end of the deep extraction pipe and the extraction manifold respectively. Since the loss of negative pressure along the airtight and smooth pipe wall is small, through the high negative pressure in the extraction manifold, high negative pressure areas are respectively formed at the inner port of the hole of the sealing pipe and the deep extraction port of the deep extraction pipe, realizing the synchronous high negative pressure extraction of the shallow and deep sections of the long borehole.
7. A directional long borehole connection and extraction method according to claim 6, characterized in that: The said deep extraction pipe passes through the sealing pipe.
8. A directional long borehole connection and extraction method according to claim 6, characterized in that: An anti-blocking screen pipe is fixed outside the deep extraction pipe at the position of the middle extraction port, and is sent into the long borehole synchronously with the deep extraction pipe to prevent the middle extraction port from being blocked due to the collapse and deformation of the borehole.
9. A directional long borehole connection and extraction device, characterized in that: For implementing the directional long borehole connection and extraction method described in any one of claims 1 to 5 or the directional long borehole connection and extraction method described in any one of claims 6 to 8, the device includes a sealing pipe, a deep extraction pipe, a deep extraction port, a middle extraction port, a deep extraction side port, an anti-blocking screen pipe, a swivel joint, a booster extraction pipe, and a booster extraction pump; wherein, the deep extraction port is the port of the deep extraction pipe placed at the deep part of the borehole, the deep extraction side port is the opening on the pipe wall of the deep extraction pipe adjacent to the deep extraction port, the deep extraction pipe passes through the sealing pipe, the middle extraction port is a through hole opened on the outer wall of the middle part of the deep extraction pipe, the other end of the deep extraction pipe is connected to the booster extraction pipe through a swivel joint, the other end of the booster extraction pipe is connected to the booster extraction pump, one end of the swivel joint is located inside the sealing pipe, and the other end passes out along the pipe wall of the sealing pipe, and the outer wall of the swivel joint is hermetically connected to the pipe wall of the sealing pipe, and an anti-blocking screen pipe is fixed outside the deep extraction pipe at the position where the middle extraction port is opened.