CN101424181B - Method and system for determining and penetrating underground coal gasification passage - Google Patents

Abstract

The invention relates to the field of underground coal gasification, in particular to a technology for determining and penetrating a coal gasification channel. The present invention provides a method and system for determining and connecting coal gasification channels, the method comprising: measuring the ground stress in the horizontal direction of the coal seam; determining the development direction of the coal seam fissures according to the measured ground stress in the horizontal direction; according to the The direction of coal seam fracture development determines the direction of the coal gasification channel. Since the development direction of the fissures in the coal seam is determined according to the in-situ stress in the horizontal direction of the coal seam, and the direction of the coal gasification channel is determined according to the development direction of the coal seam fissures, the coal gasification channels opened along the development direction of the coal seam fissures can achieve the same permeability. When the rate is low, the required external force is small, thereby improving the penetration efficiency of the gasification channel.

Description

Method and system for determining and connecting underground coal gasification channels

technical field

The invention relates to the field of underground coal gasification, in particular to a technology for determining and penetrating a coal gasification channel.

Background technique

The clean and efficient utilization of coal is one of the major issues in the field of energy and environmental protection in the world today. At present, the domestic coal that can be mined by staff only accounts for 11.43% of the coal resource reserves. For other coal resources, such as abandoned mines or uneconomical lignite or deep coal seams, it is not suitable to send personnel to dig down the mine, and It uses underground coal gasification to mine and utilize coal resources.

Underground coal gasification requires coal seams to have high gas permeability. However, the natural permeability of the coal seam is very poor, so it is necessary to penetrate the gasification channel in the coal seam before performing the underground coal gasification (UCG) operation. The gasification channel shown in Figure 1 is located between the gasification agent injection well and the gas production well, and has high gas permeability for the passage of gas. The gasification channel also helps to determine the path of the gasification process and the expansion rate of the gasification cavity, so as to control the injection rate of the gasification agent and the gas production rate, so that UCG can be controlled to a certain extent.

Before penetrating the gasification channel, the route of the gasification channel needs to be determined. At present, the judgment of the gasification channel route is to drill wells in different directions around the gasification agent injection well, then blow high-pressure gas into the gasification agent injection well, and observe the gas discharged from several wells around the gasification agent injection well. The gasification channel direction is selected as the direction of the line connecting the well with the largest exhaust gas volume and the gasification agent injection well. With this method, at least three wells need to be drilled to roughly determine the gasification channel, and the cost is relatively high; in addition, the penetration efficiency of the gasification channel determined by this method is low, and there are often gasification channels that cannot be penetrated and need to be re-determined The case where the gasification channel is penetrated again. Therefore, the method of determining and penetrating the gasification channel in the prior art has high cost and low penetrating efficiency.

Contents of the invention

Embodiments of the present invention provide a method and system for determining and connecting underground coal gasification channels, which are used to improve the efficiency of connecting gasification channels.

A method for determining a coal gasification channel, comprising:

Measure the ground stress in the horizontal direction of the coal seam;

Determine the development direction of the coal seam fissures according to the measured horizontal stress;

The direction of the coal gasification channel is determined according to the development direction of the coal seam fissures.

The in-situ stress in the horizontal direction of the measured coal seam is specifically:

obtaining at least one rock in the coal seam by directional coring;

The ground stress in the horizontal direction of the rock is measured, and the ground stress in the horizontal direction of the coal seam is determined according to the ground stress in the horizontal direction of the rock.

After said measuring the in-situ stress in the horizontal direction of the coal seam, it also includes:

The length of the coal gasification channel is determined according to the measured horizontal ground stress.

A coal gasification channel determination system, comprising:

The horizontal stress measuring device of the coal seam is used for measuring the stress of the horizontal direction of the coal seam;

A coal seam fissure development direction determining device, used to determine the coal seam fissure development direction according to the horizontal in-situ stress measured by the coal seam horizontal in-situ stress measuring device;

The coal gasification channel determination device is used to determine the direction of the coal gasification channel according to the development direction of the coal seam fissures.

A coal gasification channel penetration method, comprising:

Determine the crack development direction of the coal seam according to the measured stress in the horizontal direction of the coal seam;

determining the direction of the coal gasification channel according to the crack development direction of the coal seam;

Drilling after determining the orientation of the gas production well relative to the gasification agent injection well according to the direction of the coal gasification channel;

The coal seam between the gasification agent injection well and the gas production well runs through the coal gasification channel.

A coal gasification channel penetration system, comprising:

The horizontal stress measuring device of the coal seam is used for measuring the stress of the horizontal direction of the coal seam;

A coal seam fissure development direction determining device, used to determine the coal seam fissure development direction according to the horizontal in-situ stress measured by the coal seam horizontal in-situ stress measuring device;

A coal gasification channel determination device, configured to determine the direction of the coal gasification channel according to the development direction of the coal seam fissures;

Drilling device, used to determine the orientation of the gas production well relative to the gasification agent injection well according to the direction of the coal gasification channel, and then drill the well;

The gasification channel penetrating device is used for penetrating the coal gasification channel in the coal seam between the gasification agent injection well and the gas production well.

In the embodiment of the present invention, the development direction of the fissures in the coal seam is determined according to the in-situ stress in the horizontal direction of the coal seam, and the direction of the coal gasification channel is determined according to the development direction of the coal seam fissures, so that the coal gasification channel opened along the development direction of the coal seam fissures When the same permeability is achieved, the required external force is small, thereby improving the penetration efficiency of the gasification channel; or applying the same external force, the length of the gasification channel can be increased, thereby reducing drilling investment and saving costs.

Description of drawings

Fig. 1 is the schematic diagram of gasification agent injection well, gas production well and gasification channel in the prior art;

Fig. 2 is a flowchart of a method for determining and penetrating a coal gasification channel according to an embodiment of the present invention;

Fig. 3 is a schematic diagram of determining the development direction of coal seam cracks according to the direction of the maximum horizontal stress in the coal seam according to an embodiment of the present invention;

4 is a schematic diagram of obtaining rocks in a coal seam by directional coring in an embodiment of the present invention;

Fig. 5a is a schematic structural diagram of a system for determining a coal gasification channel according to an embodiment of the present invention;

Fig. 5b is a schematic structural diagram of a system through a coal gasification channel according to an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of a horizontal stress measurement device for a coal seam according to an embodiment of the present invention.

Detailed ways

The inventors of the present invention considered that there are often fractures in the coal seam, and the naturally formed fractures can provide effective permeation channels. Therefore, the embodiment of the present invention utilizes the cracks in the coal seam to select and penetrate the coal gasification channel. Specifically, the development direction of fissures in the coal seam (that is, the direction of the fissures) can be determined according to the measured in-situ stress in the horizontal direction of the coal seam, and the direction of the coal gasification channel can be determined according to the development direction of the coal seam fissures. In this way, opening coal gasification channels along the development direction of coal seam fractures can make the gasification channels reach the same permeability, requiring less external force, thereby improving the penetration efficiency of gasification channels; or applying the same external force, it can Increase the length of the gasification channel, thereby reducing drilling investment and saving costs.

The technical solutions of the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

A specific method for determining and penetrating the coal gasification channel provided by the embodiment of the present invention, the flow chart of which is shown in Figure 2, includes the following specific steps:

S201. Measure and determine the ground stress in the horizontal direction of the coal seam.

Since the coal seam is underground, it is impossible to directly judge the direction of its fissures. According to the principle of geological structure—the direction of the cracks in the stratum is basically consistent with the direction of the maximum horizontal stress in the stratum, so the in-situ stress in the horizontal direction of the coal seam can be measured first. , and then determine the direction of the maximum horizontal stress in the coal seam, and then determine the development direction of coal seam fractures (as shown in Figure 3).

There are currently many methods for measuring the ground stress of the formation, and those skilled in the art can choose a method most suitable for the local coal seam situation to measure the ground stress in the horizontal direction of the coal seam according to the actual situation. The specific method of measuring the in-situ stress in the horizontal direction of the coal seam will be introduced in detail later.

S202. Determine the development direction of the coal seam fractures according to the measured horizontal stress.

According to the measured horizontal ground stress, determine the direction of the maximum horizontal ground stress; according to the direction of the maximum horizontal ground stress of the coal seam, you can determine the development direction of the coal seam fissures. That is to say, the direction of the maximum horizontal stress along the coal seam is the direction of coal seam fracture development.

S203. Determine the direction of the coal gasification channel according to the development direction of the coal seam fissures.

After determining the development direction of coal seam fissures, the direction of coal seam fissure development is taken as the direction of coal gasification channel. That is to say, coal gasification channels are set along the development direction of coal seam fissures.

S204. Make the direction of the line between the gasification agent injection well and the gas production well consistent with the direction of the determined coal gasification channel.

Before the coal gasification channel is penetrated, gasification agent injection wells and gas production wells need to be drilled. Generally, the gasification agent injection well can be drilled before determining the direction of the coal gasification channel. However, the method for determining the direction of the coal gasification channel according to the embodiment of the present invention can Drill the gasification agent injection well after the direction of the gasification channel.

After determining the direction of the coal gasification channel, the orientation of the gas production well relative to the gasification agent injection well can be determined. Specifically, the direction of the connection line between the gas production well and the gasification agent injection well should be as consistent as possible with the direction of the determined coal gasification channel.

After determining the orientation of the gas production well relative to the gasification agent injection well, the gas production well can be drilled. Make the connection direction between the gas production well and the gasification agent injection well consistent with the direction of the determined coal gasification channel as far as possible, so that the coal gasification channel between the gas production well and the gasification agent injection well is along the The development direction of the coal seam fissures, so that the penetration efficiency of the coal gasification channel is high and the cost is saved.

S205. Determine the length of the coal gasification channel according to the ground stress in the horizontal direction of the fixed coal seam.

In order to further improve the penetration efficiency of the coal gasification channel, the length of the coal gasification channel can also be determined according to the in-situ stress in the horizontal direction of the coal seam, so as to more accurately determine the drilling position of the gas production well and obtain a higher coal gasification rate. The penetration efficiency of chemical channels.

For example, after considering many factors (such as the thickness of the coal seam, the effective radius of the gasification channel, the elastic modulus of the coal, the compressibility coefficient of the coal, etc.), the length value W of the coal gasification channel can be calculated by the following formula:

$\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; ah</span>}\frac{\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\frac{{\mathrm{<span\; class="notranslate">\; r</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; h</span>}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In the above formula, a is a set constant, h is the height of the working face of the channel, K is the permeability of the coal seam, _K1 is the permeability of the surrounding rock, r is the effective radius of the coal gasification channel, H is the thickness of the coal seam, and T is the breakthrough time . Among them, the coal seam permeability K can be calculated according to the difference between the maximum and minimum horizontal stress:

$\frac{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; K</span>}}{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; v</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; E.</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; ]</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Among them, K is the permeability, σ′ is the difference between the maximum horizontal stress and the minimum horizontal stress, v is the Poisson’s ratio of coal, E is the elastic modulus of coal, and C _f is the compressibility coefficient of coal.

Those skilled in the art may also use other formulas or statistical methods to obtain the relationship between the length of the coal gasification channel and the horizontal stress of the coal seam.

S206 , drilling.

After the direction of the coal gasification channel is determined, the orientation of the gas production well relative to the gasification agent injection well can be determined, and then the drilling of the gas production well can be implemented.

In order to further improve the penetration efficiency of the coal gasification channel, the length of the coal gasification channel can also be determined, and the distance between the gas production well and the gasification agent injection well can be determined according to the length of the coal gasification channel, and then the gas production well can be implemented. drilling.

S207, the coal seam between the gasification agent injection well and the gas production well runs through the coal gasification channel.

A variety of methods can be used to penetrate the coal gasification channel between the gasification agent injection well and the gas production well, including but not limited to: electric penetration, hydraulic fracturing, air fire penetration, directional drilling and other methods.

The electric power penetration method is to apply an alternating current of industrial frequency to the coal seam. With the help of the thermal effect of electric energy, the physical structure of the coal seam will be destroyed, and a narrow gas permeable burnt-through coal seam will be formed in the coal seam between the electrodes in the two boreholes. The coking channel is expanded through thermal processing, so that the gasification channel is penetrated in the coal seam between the drill holes.

The hydraulic fracturing method is to inject a high-pressure solution into the coal seam, and the high-pressure solution flows through the coal seam, and a channel is opened in the coal seam between two drill holes as a gasification channel.

The air fire infiltration method uses the natural gas permeability of the coal seam to regard the gasified coal seam as a natural coal seam composed of coal blocks separated by pores and cracks. A gasification channel is established in the coal seam between the two boreholes.

After the coal gasification channel is determined according to the direction of crack development in the coal seam, the gasification channel is further established through penetration methods such as pressure, water or fire, which is conducive to the further development of cracks in the coal seam, thereby ensuring that the coal seam has a high gas permeability. This helps to improve heat transfer, mass transfer and reaction intensity during the gasification process, strengthens the cracks in the coal seam, and improves the gasification efficiency and gas yield.

The above-mentioned step S201 measures the ground stress in the horizontal direction of the coal seam, which can be realized by various methods at present, such as: hydraulic fracturing stress measurement method, shaft wall caving stress direction measurement, long source distance acoustic wave stress measurement, surface potential method stress direction measurement, underground Micro-seismic wave method to measure the stress direction of the earth, the stress relief of the sleeve core and other mine field stress measurement methods;

Or, use geological and seismic data, such as volcanic neck, fault type, oil well borehole stability, coring yield, stratum undulation, geological structure, focal mechanism, etc., to conduct qualitative analysis to obtain the stress field distribution of the coal seam, so as to determine the In-situ stress in the horizontal direction of the coal seam;

Or, use methods such as finite element numerical simulation of stress field, interpretation of in-situ stress profile, inversion of drilling parameters, self-adaptation of long source distance acoustic wave logging, etc. to calculate the in-situ stress in the horizontal direction of the coal seam;

Or the stratum to be measured——the horizontal stress of the coal seam can be obtained through the core measurement method. Those skilled in the art can choose the method that is most in line with the actual situation to measure the ground stress in the horizontal direction of the coal seam.

Among them, the preferred method is the core measurement method. Since the core measurement can be determined indoors, it does not require a large number of on-site equipment and personnel, so it has a lower cost. The core measurement method mainly uses the Kaiser effect of the rock to measure the horizontal stress of the rock in the coal seam. Since the stress in the horizontal direction of the rock reflects the stress in the horizontal direction of the coal seam, it can be measured by measuring at least The in-situ stress in the horizontal direction of a rock is used to determine the in-situ stress in the horizontal direction of the coal seam. Since the rock is usually taken out of the coal seam to measure its horizontal in-situ stress; therefore, in order to ensure that the horizontal in-situ stress of the rock tested after taking out can reflect the horizontal in-situ stress of the coal seam where it is located, it is necessary to ensure that the position of the rock after it is taken out The state is consistent with the position state in the seam. That is to say, the rock cannot be overturned or rotated during the process of taking and testing the rock, otherwise, the horizontal in-situ stress of the tested rock cannot reflect the horizontal in-situ stress of the coal seam where it is located. Therefore, using the directional coring method to obtain the rocks in the coal seam can maintain the posture of the rocks in the coal seam (as shown in Figure 4), so that the measured horizontal stress of the rock can reflect the level of the coal seam where it is located. direction of stress.

The Kaiser effect of the rock means that the rock has a memory function for the stress it has suffered. When the external stress reaches the maximum previous stress suffered by the rock, the rock begins to show obvious acoustic emission phenomena. Using the Kaiser effect of the rock, the stress can be gradually increased to the rock through the press in the horizontal direction, the stress-strain relationship of the rock can be recorded, and the acoustic emission frequency of the rock during the stress increase process can be tested. Stress, so that the maximum or minimum in-situ stress direction in the horizontal direction of the rock can be obtained.

Those skilled in the art can understand that although in the above description, the steps of the method are described sequentially for ease of understanding, it should be noted that the sequence of the steps is not strictly limited.

A system for determining a coal gasification channel provided by an embodiment of the present invention, as shown in FIG. 5 a , includes: a device for measuring horizontal stress in the coal seam 501 , a device for determining the development direction of coal seam fissures 502 , and a device for determining the coal gasification channel 503 .

The horizontal stress measuring device 501 of the coal seam is used to measure the horizontal stress of the coal seam. The specific measurement method may adopt the measurement method introduced above, and will not be repeated here.

The coal seam fracture development direction determination device 502 is used to determine the coal seam fracture development direction according to the horizontal ground stress measured by the coal seam horizontal ground stress measurement device. The coal seam fracture development direction determining device 502 determines the coal seam fracture development direction according to the direction of the maximum horizontal stress in the horizontal direction of the coal seam.

The coal gasification channel determination device 503 is used to determine the direction of the coal gasification channel according to the development direction of the coal seam fissures. The coal gasification channel determination device 503 determines that the direction of the coal gasification channel is as consistent as possible with the development direction of coal seam fissures.

Further, the coal gasification channel determination device 503 is also used to determine the length of the coal gasification channel according to the horizontal ground stress measured by the coal seam horizontal ground stress measuring device. The specific method for determining the length of the coal gasification channel is as described above, and will not be repeated here.

A specific structure of the coal seam horizontal stress measurement device 501 is shown in FIG. 6 , including: a rock acquisition module 601 , a rock horizontal stress measurement module 602 , and a coal seam horizontal stress determination module 603 .

The rock acquisition module 601 is used to acquire at least one rock in the coal seam in a directional coring manner;

The rock horizontal stress measurement module 602 is used to measure the horizontal stress of the rock;

The horizontal stress determination module 603 of the coal seam is used to determine the horizontal stress of the coal seam according to the horizontal stress of the rock.

A system for penetrating coal gasification channels provided by an embodiment of the present invention, as shown in Figure 5b, includes the above-mentioned device for measuring the horizontal stress of the coal seam 501, a device for determining the development direction of coal seam fissures 502, and a device for determining the coal gasification channel In addition to 503, it also includes: a drilling device 504 and a gasification passage penetrating device 505.

Wherein, the drilling device 504 is used to determine the orientation of the gas production well relative to the gasification agent injection well according to the direction of the coal gasification channel determined by the coal gasification channel determination device 503 before drilling.

The gasification channel penetrating device 505 is used for penetrating the coal gasification channel in the coal seam between the gasification agent injection well and the gas production well. The specific penetration method may adopt one of the aforementioned penetration methods.

Further, the drilling device 504 is also used to determine the distance between the gas production well and the gasification agent injection well according to the length of the coal gasification channel determined by the coal gasification channel determination device 503 before drilling; Drilling is carried out after determining the azimuth and distance of the agent injection well, which can make the penetration efficiency of the coal gasification channel between the gas production well and the gasification agent injection well higher.

In the embodiment of the present invention, the development direction of the fissures in the coal seam is determined according to the in-situ stress in the horizontal direction of the coal seam, and the direction of the coal gasification channel is determined according to the development direction of the coal seam fissures, so that the coal gasification channel opened along the development direction of the coal seam fissures When the same permeability is achieved, the required external force is small, thereby improving the penetration efficiency of the gasification channel; or applying the same external force, the length of the gasification channel can be increased, thereby reducing drilling investment and saving costs.

After the coal gasification channel is determined according to the direction of crack development in the coal seam, the gasification channel is further established through penetration methods such as pressure, water or fire, which is conducive to the further development of cracks in the coal seam, thereby ensuring that the coal seam has a high gas permeability. This helps to improve heat transfer, mass transfer and reaction intensity during the gasification process, strengthens the cracks in the coal seam, and improves the gasification efficiency and gas yield.

In addition, because the coal seam is in a relatively shallow stratum, in this geological environment, the maximum horizontal stress is several times the minimum horizontal stress and vertical stress. The ground stress around the channel is minimal, which reduces the possibility of gasification channel collapse and blockage and the damage of rock creep to the casing in the wellbore to a certain extent.

Those of ordinary skill in the art can understand that all or part of the steps in the method of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as: ROM/RAM, Diskettes, CDs, etc.

It can also be understood that the device structures shown in the drawings or embodiments are only schematic and represent logical structures. Where modules shown as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications should also be It is regarded as the protection scope of the present invention.

Claims (10)

1. A method for determining a coal gasification channel, comprising: Measure the ground stress in the horizontal direction of the coal seam; Determine the development direction of the coal seam fissures according to the measured horizontal stress; determining the direction of the coal gasification channel according to the development direction of the coal seam fissure; After measuring the horizontal stress of the coal seam, the method further includes: determining the length of the coal gasification channel according to the measured horizontal stress. 2. The method according to claim 1, characterized in that, the geostress in the horizontal direction of the measured coal seam is specifically: obtaining at least one rock in the coal seam by directional coring; The ground stress in the horizontal direction of the rock is measured, and the ground stress in the horizontal direction of the coal seam is determined according to the ground stress in the horizontal direction of the rock. 3. The method according to claim 1, wherein the geostress in the horizontal direction of the measured coal seam specifically includes but is not limited to: Using hydraulic fracturing stress measurement methods, shaft wall caving stress direction measurement methods, long source distance acoustic stress measurement methods, ground potential method stress direction measurement methods, or downhole microseismic wave measurement methods to measure the ground stress in the horizontal direction of the coal seam; or Using geological and seismic data to qualitatively analyze the stress field distribution of the coal seam, so as to determine the horizontal stress of the coal seam; or The in-situ stress in the horizontal direction of the coal seam is calculated by means of stress field finite element numerical simulation, in-situ stress profile interpretation, drilling parameter inversion or long source distance acoustic logging method. 4. A coal gasification channel determination system, characterized in that it comprises: The horizontal stress measuring device of the coal seam is used for measuring the stress of the horizontal direction of the coal seam; A coal seam fissure development direction determining device, used to determine the coal seam fissure development direction according to the horizontal in-situ stress measured by the coal seam horizontal in-situ stress measuring device; A coal gasification channel determination device, configured to determine the direction of the coal gasification channel according to the development direction of the coal seam fissures; The coal gasification passage determination device is also used to determine the length of the coal gasification passage according to the horizontal ground stress measured by the coal seam horizontal ground stress measurement device. 5. The system according to claim 4, wherein the stress measuring device in the horizontal direction of the coal seam comprises: a rock acquisition module, configured to acquire at least one rock in the coal seam in a directional coring manner; A rock horizontal stress measurement module, used to measure the horizontal stress of the rock; The horizontal stress determination module of the coal seam is used to determine the horizontal stress of the coal seam according to the horizontal stress of the rock. 6. A coal gasification channel penetration method, characterized in that it comprises: Determine the crack development direction of the coal seam according to the measured stress in the horizontal direction of the coal seam; determining the direction of the coal gasification channel according to the crack development direction of the coal seam; Drilling after determining the orientation of the gas production well relative to the gasification agent injection well according to the direction of the coal gasification channel; The coal seam between the gasification agent injection well and the gas production well runs through the coal gasification channel; Before said drilling, also include: The length of the coal gasification channel is determined according to the measured ground stress in the horizontal direction of the coal seam. 7. The method of claim 6, further comprising: According to the length of the coal gasification channel, the distance between the gas production well and the gasification agent injection well is determined. 8. The method according to claim 6, characterized in that, the through coal gasification channel specifically includes but not limited to: The coal gasification channel is penetrated by means of air fire penetration, electric power penetration, hydraulic fracturing or directional drilling. 9. A coal gasification channel penetration system, characterized in that it comprises: The horizontal stress measuring device of the coal seam is used for measuring the stress of the horizontal direction of the coal seam; A coal seam fissure development direction determining device, used to determine the coal seam fissure development direction according to the horizontal in-situ stress measured by the coal seam horizontal in-situ stress measuring device; The coal gasification channel determination device is used to determine the direction of the coal gasification channel according to the development direction of the coal seam fissure; the coal gasification channel determination device is also used to determine the direction of the coal gasification channel according to the level The geostress in the direction determines the length of the coal gasification channel; Drilling device, used to determine the orientation of the gas production well relative to the gasification agent injection well according to the direction of the coal gasification channel, and then drill the well; The gasification channel penetrating device is used for penetrating the coal gasification channel in the coal seam between the gasification agent injection well and the gas production well. 10. The system of claim 9, wherein: The drilling device is also used to determine the distance between the gas production well and the gasification agent injection well according to the length of the coal gasification channel determined by the coal gasification channel determination device before drilling.

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