Stratum filling type hydrate mining method and device

Abstract

The invention belongs to the technical field of natural gas hydrate exploitation engineering, and discloses a stratum filling type hydrate exploitation method and device. The stratum filling type hydrate mining method comprises the steps that firstly, a production well is drilled to the junction of a hydrate reservoir and a free gas layer; drilling a filling well to the junction position of the upper covering layer and the hydrate reservoir; production pipe columns are tripped into the production well and the filling well respectively, and the production well exploits the gaseous hydrate of the free gas layer; and a perforation fracturing tool is tripped into the filling well, perforation fracturing operation is conducted on the hydrate reservoir, a fracturing channel is formed in the hydrate reservoir, and solid hydrate of the hydrate reservoir is decomposed, continuously transported to the free gas layer through the fracturing channel and continuously supplied to the production well for exploitation. The continuous, stable and efficient gas production function of the production well is achieved, and the problems that stratum energy supplement is insufficient and stratum stability control is insufficient are solved.

Description

Technical Field

[0001] The invention relates to the technical field of natural gas hydrate exploitation engineering, and in particular to a formation filling type hydrate exploitation method and device. Background Art

[0002] Natural gas hydrates are mainly distributed in terrestrial permafrost zones with harsh engineering conditions and seabed sediments with a water depth of more than 300m, and more than 90% are distributed in marine areas. According to the structural characteristics of hydrate reservoirs, they can be divided into four levels: there is a free gas-water layer below the first-class hydrate layer; there is only an aquifer below the second-class hydrate layer; there is no fluid layer below the third-class hydrate layer; and there are extremely low-content hydrate particles with no development value in the fourth-class seabed mudstone. Under the existing mining technology conditions, the first-class hydrate resource type belongs to the most valuable reservoir type with high mining prospects. It is the target ore body type for the future commercial exploitation of large-scale natural gas hydrates.

[0003] In the process of first-class hydrate reservoir exploitation, hydrates need to absorb a large amount of heat when they are converted from solid to gas. When the heat of the formation cannot be met, secondary hydrate generation occurs, causing blockage of production pipelines, affecting the efficiency and capacity of further exploitation. When the conditions for hydrate exploitation are met, the large-scale decomposition of hydrates will cause changes in the mechanical properties of seabed sediments, and the bottom layer will have local weak areas due to excessive weight, thus causing large-scale geological collapse, landslides, natural gas leaks and other natural disasters and environmental problems. Therefore, the existing hydrate reservoir exploitation process urgently needs to solve the problems of insufficient formation energy replenishment and formation stability control. Summary of the invention

[0004] The object of the present invention is to provide a formation-filling hydrate production method and device to solve the problems of insufficient formation energy replenishment and formation stability control.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] The present invention provides a hydrate production method of formation filling type, wherein the formations are, from top to bottom, an upper covering layer, a hydrate reservoir, a free gas layer and a lower covering layer; the hydrate production method of formation filling type comprises the following steps:

[0007] S1, drilling a production well so that the bottom of the production well is located at the junction of the hydrate reservoir and the free gas layer;

[0008] S2, drilling a filling well, wherein a safety distance exists between the filling well and the production well, and the filling well comprises a horizontal section, and the horizontal section is located at the junction of the upper covering layer and the hydrate reservoir;

[0009] S3, lowering production pipes into the production well and the filling well respectively, and the production well exploits the gas hydrate in the free gas layer;

[0010] S4, placing a perforating and fracturing tool into the filling well, performing perforating and fracturing operations on the hydrate reservoir, forming a fracturing channel in the hydrate reservoir, and the solid hydrate in the hydrate reservoir is decomposed and continuously transported to the free gas layer through the fracturing channel, and continuously supplied to the production well for exploitation.

[0011] In some embodiments, in step S3, the production well is produced by a pressure reduction production method, so that the free gas layer forms a negative pressure state.

[0012] In some embodiments, in step S4, support materials and hot seawater are continuously injected during the perforation and fracturing operation to continuously promote the decomposition of solid hydrates in the hydrate reservoir.

[0013] In some embodiments, there are multiple filling wells, and the multiple filling wells are evenly spaced around the production well.

[0014] The present invention also provides a formation-filling type hydrate production device, which is used to implement the formation-filling type hydrate production method; the formation-filling type hydrate production device comprises:

[0015] A production well, the bottom of which reaches directly to the junction of the hydrate reservoir and the free gas layer;

[0016] A filling well, the filling well being arranged at a safe distance from the production well, the filling well comprising a horizontal section, the horizontal section being located at a junction of an upper overburden and the hydrate reservoir;

[0017] A perforation and fracturing tool is used to perform perforation and fracturing operations on the hydrate reservoir so that the solid hydrates in the hydrate reservoir are decomposed into gaseous hydrates and a fracturing channel is formed in the hydrate reservoir. The gaseous hydrates are continuously transported to the free gas layer through the fracturing channel to meet the continuous exploitation of the production well.

[0018] In some embodiments, both the production well and the filling well are provided with a cementing assembly, and the cementing assembly comprises:

[0019] A cementing casing, the cementing casing being arranged in the open hole trajectory of the production well and the filling well;

[0020] A cementing ring, the cementing ring being arranged between the cementing casing and the formation;

[0021] A production string, wherein the production string is arranged in the cementing casing, and the bottom end of the production string in the production well extends into the free gas layer for hydrate production; the production string in the filling well is used to fix the perforating and fracturing tool and inject supporting materials and hot seawater.

[0022] In some embodiments, a plurality of the perforating and fracturing tools are provided, and the plurality of the perforating and fracturing tools are evenly spaced along the horizontal section to form a plurality of the fracturing channels in the horizontal section.

[0023] In some embodiments, there are multiple filling wells, and the multiple filling wells are evenly spaced around the production well.

[0024] In some embodiments, there are two filling wells, and the two filling wells are symmetrically arranged on both sides of the production well.

[0025] In some embodiments, the production well is a vertical well arranged in a vertical direction, the filling well is a horizontal well, and the horizontal section of the filling well extends away from the production well in a horizontal direction.

[0026] Beneficial effects of the present invention:

[0027] The formation filling type hydrate production method provided by the present invention has the bottom of the production well located at the junction of the hydrate reservoir and the free gas layer, and can directly produce the gaseous hydrate in the free gas layer. As the production time goes by, the free gas layer forms a negative pressure state. By drilling a filling well and performing perforation and fracturing in the hydrate reservoir in the filling well, solid hydrates are decomposed into gaseous hydrates. Under the action of negative pressure, the decomposed gaseous hydrates replenish the free gas layer as a resource, thereby realizing the continuous, stable and efficient gas production function of the production well, solving the problems of insufficient formation energy replenishment and insufficient formation stability control. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of a formation filling type hydrate production device provided by the present invention;

[0029] Figure 2 yes Figure 1 Schematic diagram of the enlarged structure of area A in the middle.

[0030] In the figure:

[0031] 1. Production well; 2. Filling well; 3. Production tubing; 4. Cementing casing; 5. Cementing cement ring; 6. Hydraulic perforation holes; 7. Fracturing channel;

[0032] a, seawater layer; b, upper covering layer; c, hydrate reservoir; d, free gas layer; e, lower covering layer. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0037] The object of the present invention is to provide a formation-filling hydrate production method and device for producing natural gas hydrates. Figure 1 and Figure 2 As shown, this embodiment takes the mining of the strata below the seawater layer a as an example for detailed description. The strata from top to bottom are the upper cover layer b, the hydrate reservoir layer c, the free gas layer d and the lower cover layer e.

[0038] The formation filling type hydrate production method comprises the following steps:

[0039] S1, drilling production well 1, the bottom of production well 1 is located at the junction of hydrate reservoir c and free gas layer d;

[0040] S2, drilling a filling well 2, which is located at a safe distance from the production well 1. The filling well 2 includes a horizontal section, which is located at the junction of the upper overburden b and the hydrate reservoir c;

[0041] S3, lowering the production string 3 into the production well 1 and the filling well 2 respectively, and the production well 1 exploits the gas hydrate in the free gas layer d;

[0042] This step is a cementing step. First, cementing casing 4 is lowered into the open hole trajectory of production well 1 and filling well 2 respectively. Then cement is injected between cementing casing 4 and the formation to form cementing cement ring 5. Finally, production string 3 is lowered into cementing casing 4 to form an annulus between production string 3 and cementing casing 4. Among them, the bottom end of production well 1 is located at the junction of hydrate reservoir c and free gas layer d. Production string 3 protrudes from the bottom of production well 1 and extends into free gas layer d to directly exploit free gas.

[0043] S4, a perforating and fracturing tool is lowered into the filling well 2 to perform perforating and fracturing operations on the hydrate reservoir c, forming a fracturing channel 7 in the hydrate reservoir c, and the solid hydrate in the hydrate reservoir c is decomposed and continuously transported to the free gas layer d through the fracturing channel 7, and continuously supplied to the production well 1 for exploitation.

[0044] In the formation filling type hydrate mining method provided by the present invention, the bottom of the production well 1 is located at the junction of the hydrate reservoir c and the free gas layer d, and the gaseous hydrates in the free gas layer d can be directly mined. As the mining time goes by, the free gas layer d forms a negative pressure state, inducing the decomposed gaseous hydrates in the upper hydrate reservoir c to supplement the free gas layer d, thereby realizing the continuous and stable efficient gas production function of the production well 1. Afterwards, a filling well 2 is drilled around the production well 1, and perforation and fracturing are performed in the filling well 2 into the hydrate reservoir c to decompose the solid hydrate into gaseous hydrates. Under the action of negative pressure, the decomposed gaseous hydrates are continuously supplemented to the free gas layer d, thereby realizing the continuous and stable efficient gas production function of the production well 1, solving the problem of insufficient formation energy supplement and insufficient formation stability control. It should be noted that the safety distance between the filling well 2 and the production well 1 is set according to the actual situation of the mining site, and there is no fixed value, which meets the mining efficiency and safety requirements during the mining process.

[0045] In some embodiments, in step S3, the production well 1 is mined by a reduced pressure mining method, so that the free gas layer d forms a negative pressure state. Since the free gas layer d is rich in free methane gas and water, stable production can be carried out at the rate actually designed for the hydrate mining project. The reduced pressure mining method is a prior art. The production well 1 continues to perform reduced pressure mining, and the negative pressure state of the free gas layer d can be continuously maintained. During the reduced pressure mining process, it is also necessary to comprehensively consider the stability of the free gas layer d, the formation sand characteristics and stability of the hydrate reservoir c, the hydrate decomposition amount and diversion transmission rate of the horizontal section of the filling well 2 after the perforation and fracturing operation, the safety of the mining project, the processing and transportation efficiency of the output gaseous methane gas, and other influencing factors, and design a reasonable reduced pressure mining value, so as to maintain the continuous, stable, efficient and economical mining efficiency of the production well 1.

[0046] In some embodiments, in step S4, support materials and hot seawater are continuously injected during the perforation and fracturing operation to continuously promote the decomposition of solid hydrates in the hydrate reservoir c.

[0047] Among them, the supporting material is quartz sand with a larger mesh size. During the perforation and fracturing operation, hydraulic perforation holes 6 are generated in the horizontal section of the filling well 2. The supporting material is filled into the hydraulic perforation holes 6, which is conducive to the establishment of fracturing channels 7, playing a role in supporting the formation and improving the stability of the formation. The seawater is heated to the temperature required by the actual project through the liquid storage heating equipment to obtain hot seawater. The main function of the hot seawater is to promote the decomposition of hydrates and replenish the energy of the formation. The support material and hot seawater can quickly decompose part of the methane hydrate, enhance the fracturing effect, and form a stable fracturing channel 7 in the hydrate reservoir c to connect the horizontal section of the filling well 2 and the free gas layer d, thereby providing methane gas and water to the free gas layer d.

[0048] In some embodiments, there are multiple filling wells 2, and the multiple filling wells 2 are evenly arranged around the production well 1. Preferably, there are two filling wells 2, which are symmetrically arranged on both sides of the production well 1.

[0049] In the present invention, the main functions of the filling well 2 include two aspects. On the one hand, by transforming the hydrate reservoir c and injecting hot seawater, the formation energy is continuously replenished to promote the decomposition of solid hydrates in the hydrate reservoir c to form gaseous hydrates (including methane and water); on the other hand, the hydrate reservoir c is filled with supporting materials to achieve the control of formation stability, and a fracturing channel 7 is established to achieve communication between the hydrate reservoir c and the free gas layer d, thereby continuously improving the mining efficiency of the production well 1.

[0050] It should be noted that before executing the formation filling type hydrate mining method of the present invention, it also includes the steps of mining site selection and well construction. Mining site selection refers to exploring the internal distribution of the underlying hydrate reservoir c with free gas, determining the position information of the bottom of the upper cover layer b, the top of the hydrate reservoir c and the top of the free gas layer, so as to determine the drilling position and depth. Well construction refers to building an offshore mining platform to drill the production well 1 and deploying a drilling and mining ship to drill the filling well 2. The offshore mining platform is equipped with a gas-liquid separation storage device. The hydrate mined from the production well 1 is a gas-liquid mixture. After the gas-liquid mixture is mined, it is first subjected to a gas-liquid separation process. After the formation water is separated, it is subjected to reasonable environmental protection treatment. After the harmful heavy metal substances are removed, it is discharged in a reasonable area; the pure methane gas obtained after separation is stored in a gas storage tank for storage and transportation.

[0051] The embodiment of the present invention further provides a formation-filling hydrate production device, which is used to implement a formation-filling hydrate production method; Figure 1 and Figure 2 The formation-filling hydrate production device comprises a production well 1, a filling well 2 and a perforating and fracturing tool. The bottom of the production well 1 reaches directly to the boundary between the hydrate reservoir c and the free gas layer d. The filling well 2 is arranged at a safe distance from the production well 1. The filling well 2 comprises a horizontal section. The horizontal section is located at the boundary between the upper covering layer b and the hydrate reservoir c. The perforating and fracturing tool is lowered into the horizontal section to perform perforating and fracturing operations. The perforating and fracturing tool is used to perform perforating and fracturing operations on the hydrate reservoir c so that the solid hydrate in the hydrate reservoir c is decomposed into gaseous hydrate, and the gaseous hydrate is continuously transported to the free gas layer d to meet the continuous production of the production well 1.

[0052] Among them, the number of filling wells 2 can be multiple, and multiple filling wells 2 are evenly spaced around the production well 1. In this embodiment, two filling wells 2 are provided, and the two filling wells 2 are symmetrically arranged on both sides of the production well 1. The safety distance between the filling well 2 and the production well 1 needs to comprehensively consider the drilling and production safety of the drilling and production ship and the formation stability and production rate during the long-term production process. The two filling wells 2 can be mined at the same time, or additional filling wells 2 can be added as needed during the hydrate production process. By setting up the filling well 2, the hydrate reservoir c around the production well 1 can be perforated and fractured through the filling well 2, so that the solid hydrate in the hydrate reservoir c is decomposed into gaseous hydrates, and under the negative pressure of the free gas layer d, the gaseous hydrate is transported to the free gas layer d to meet the continuous production of the production well 1. It can be understood that the perforation and fracturing operation is oriented toward the hydrate reservoir c, and hydraulic perforation holes 6 will be formed in the hydrate reservoir c, which will then serve as a fracturing channel 7, which is conducive to the directional transfer and transportation of the decomposed gaseous hydrates.

[0053] In some embodiments, both the production well 1 and the filling well 2 are provided with cementing assemblies, which include cementing casing 4, cementing cement ring 5 and production tubing 3, wherein the cementing casing 4 is respectively arranged in the open hole trajectories of the production well 1 and the filling well 2, the cementing casing 4 is arranged to penetrate the axial direction of the production well 1 and the filling well 2, the cementing cement ring 5 is arranged between the cementing casing 4 and the formation, and is formed by injecting cement between the formation below the seawater layer a and the cementing casing 4; the production tubing 3 is arranged in the cementing casing 4, and the bottom end of the production tubing 3 in the production well 1 extends into the free gas layer d, which is used for direct exploitation from the free gas layer d; the production tubing 3 in the filling well 2 is used to fix the perforating and fracturing tools and inject supporting materials and hot seawater.

[0054] The present invention realizes the transformation of the hydrate reservoir c by drilling a filling well 2. By setting a perforation and fracturing tool in the filling well 2, supporting materials and hot seawater can be injected to perform perforation and fracturing operations. The supporting material uses quartz sand of larger size. The supporting material can play the role of establishing a fracturing channel 7 and supporting the formation in the hydrate reservoir c, connecting the hydrate reservoir c between the horizontal section of the filling well 2 and the free gas layer d, and guiding the decomposed methane gas and water to be transported to the underlying free gas layer d. The formation position after the decomposition of the solid hydrate can be continuously replaced by the continuously filled supporting material, and the formation can be stabilized without additional processes and measures, and the overall balanced stable state of the hydrate reservoir c can be achieved, which is conducive to improving the stability and safety of the continuous reservoir transformation construction of the hydrate reservoir c. Hot seawater can promote the decomposition of hydrates, and continuously replenish the heat energy lost by the formation under the influence of hydrate decomposition, replenish the formation energy, and thus keep the hydrate reservoir c in a stable state of solid-state hydrate decomposition. In addition, the injection of hot seawater can prevent the secondary generation of hydrates in the hydrate reservoir c, maintain the flow stability of the fracturing channel 7, improve the fracturing and fracturing effect of the hydrate reservoir c transformation, and improve the hydrate decomposition efficiency and migration rate of the hydrate reservoir c.

[0055] In some embodiments, a plurality of perforating and fracturing tools are provided, and the plurality of perforating and fracturing tools are evenly spaced along the horizontal section. The plurality of perforating and fracturing tools are spaced along the horizontal section of the filling well 2, so that the hydrate reservoir c region covered by the horizontal section can obtain a plurality of uniform and consistent fracturing channels 7, thereby achieving uniform support and stable exploitation of the hydrate reservoir c, and ensuring formation stability.

[0056] In some embodiments, the production well 1 is a vertical well arranged in the vertical direction, the filling well 2 is a horizontal well, and the horizontal section of the filling well 2 extends away from the production well 1 in the horizontal direction.

[0057] In the embodiment of the present invention, the production well 1 is a vertical well, and the method of directly exploiting the free gas layer d has the advantage of reducing the amount and impact of formation sand entering the production string 3 during the production process, and is not easy to cause blockage in the production string 3 and reduce the hydrate extraction efficiency. No formation sand is carried out with the extraction, which is convenient for separating and processing the extracted hydrate mixture, further improving the extraction efficiency and economy. On the other hand, it can reduce the secondary generation of hydrates in the production string 3 during the production process. Since the hydrate reservoir c is in a state of continuous formation energy replenishment in the filling well 2, the hydrate reservoir c around the production well 1 is also in a stable state of solid hydrate decomposition into gaseous hydrates. Therefore, the temperature and pressure conditions for secondary generation of hydrates will not appear in the production string 3, and the continuous and stable hydrate extraction efficiency can be maintained.

[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A hydrate production method of formation filling type, wherein the formations are, from top to bottom, an upper covering layer (b), a hydrate reservoir layer (c), a free gas layer (d) and a lower covering layer (e); characterized in that: The formation filling type hydrate production method comprises the following steps: S1, drilling a production well (1) so that the bottom of the production well (1) is located at the junction of the hydrate reservoir (c) and the free gas layer (d); S2, drilling a filling well (2), wherein a safety distance is provided between the filling well (2) and the production well (1), and the filling well (2) comprises a horizontal section, and the horizontal section is located at the interface between the upper covering layer (b) and the hydrate reservoir (c); S3, lowering production pipes (3) into the production well (1) and the filling well (2), respectively, and the production well (1) exploits the gaseous hydrates in the free gas layer (d); S4, inserting a perforating and fracturing tool into the filling well (2), performing perforating and fracturing operations on the hydrate reservoir (c), forming a fracturing channel (7) in the hydrate reservoir (c), and the solid hydrate in the hydrate reservoir (c) is decomposed and continuously transported to the free gas layer (d) through the fracturing channel (7), and continuously supplied to the production well (1) for exploitation.

2. The formation filling type hydrate production method according to claim 1, characterized in that: In step S3, the production well (1) is produced by a pressure reduction production method, so that the free gas layer (d) forms a negative pressure state.

3. The formation filling type hydrate production method according to claim 1, characterized in that: In step S4, support materials and hot seawater are continuously injected during the perforation and fracturing operation to continuously promote the decomposition of solid hydrates in the hydrate reservoir (c).

4. The formation filling type hydrate production method according to claim 1, characterized in that: There are a plurality of filling wells (2), and the plurality of filling wells (2) are evenly spaced around the production well (1).

5. A formation-filling hydrate production device, used to implement the formation-filling hydrate production method according to any one of claims 1 to 4, characterized in that: The formation filling type hydrate production device comprises: A production well (1), the bottom of which directly reaches the boundary between the hydrate reservoir (c) and the free gas layer (d); A filling well (2), the filling well (2) being arranged at a safe distance from the production well (1), the filling well (2) comprising a horizontal section, the horizontal section being located at the interface between the upper overburden (b) and the hydrate reservoir (c); A perforation and fracturing tool is used to perform perforation and fracturing operations on the hydrate reservoir (c) so that the solid hydrates in the hydrate reservoir (c) are decomposed into gaseous hydrates, and a fracturing channel (7) is formed in the hydrate reservoir (c). The gaseous hydrates are continuously transported to the free gas layer (d) through the fracturing channel (7) to meet the continuous exploitation of the production well (1).

6. The formation filling type hydrate production device according to claim 5, characterized in that: The production well (1) and the filling well (2) are both provided with a cementing assembly, and the cementing assembly comprises: A cementing casing (4), the cementing casing (4) being arranged in the open hole trajectory of the production well (1) and the filling well (2); A cementing ring (5), wherein the cementing ring (5) is arranged between the cementing casing (4) and the formation; A production tubing string (3), wherein the production tubing string (3) is arranged in the cementing casing (4), and the bottom end of the production tubing string (3) in the production well (1) extends into the free gas layer (d) for hydrate production; the production tubing string (3) in the filling well (2) is used to fix the perforation and fracturing tool and inject support materials and hot seawater.

7. The formation filling type hydrate production device according to claim 5, characterized in that: The perforating and fracturing tools are provided in plurality, and the plurality of perforating and fracturing tools are evenly spaced along the horizontal section to form a plurality of fracturing channels (7) in the horizontal section.

8. The formation filling type hydrate production device according to claim 5, characterized in that: There are a plurality of filling wells (2), and the plurality of filling wells (2) are evenly spaced around the production well (1).

9. The formation filling type hydrate production device according to claim 8, characterized in that: There are two filling wells (2), and the two filling wells (2) are symmetrically arranged on both sides of the production well (1).

10. The formation filling type hydrate production device according to claim 5, characterized in that: The production well (1) is a vertical well arranged in a vertical direction, the filling well (2) is a horizontal well, and the horizontal section of the filling well (2) is arranged to extend away from the production well (1) in a horizontal direction.

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