Rock fracture model and device and method for transporting and paving proppant in rock fracture

Abstract

The invention discloses a rock fracture model and a device and a method for transporting and paving a propping agent in a rock fracture. Relates to the technical field of geological exploration and development, and comprises a rock fracture model which comprises a rock model main body, and rough surfaces of two rocks are combined to form a fracture. The device for transporting and paving the propping agent in the rock crack comprises a supporting assembly which comprises a placing frame and a lifting frame, a rock model main body is arranged on the placing frame, a plurality of through holes are formed in the placing frame, and an illuminating lamp is arranged in each through hole; the conveying assembly comprises a mixer, a storage cylinder and a pouring connector, the mixer communicates with the storage cylinder through a pipeline, a stirrer is arranged in the mixer, a temperature regulator is arranged in the storage cylinder, the storage cylinder communicates with the crack through a conveying pipeline, and a variable-frequency conveying pump is arranged at the end, close to the storage cylinder, of the conveying pipeline. A pouring joint is arranged at the joint of the conveying pipeline and the crack; and a gas flow controller. According to the method, the proppant can be regularly distributed along with time under the precise crack specification, and observation is convenient.

Description

Technical Field

[0001] The invention relates to the technical field, and more particularly to a rock fracture model and a device and method for moving and placing proppant in rock fractures. Background Art

[0002] Proppant refers to natural sand or artificial high-strength ceramic particles with a certain particle size and gradation. Ceramic proppant is made of bauxite as raw material, through powder granulation and sintering. It has the characteristics of high temperature resistance, high pressure resistance, corrosion resistance, high strength, high conductivity, low density, low breakage rate, etc., and is the most widely used.

[0003] Coating resin on the surface of sand or ceramsite can further improve the strength and conductivity of the proppant. Proppant is a key material in fracturing construction.

[0004] Since the fracture walls formed by fracturing are rough, complex in shape and long in length, it is difficult for the proppant to migrate in the fractures. Therefore, the migration state of the proppant in the fractures is a factor that affects the success or failure of fracturing and largely determines the final oil and gas production increase effect.

[0005] Therefore, accurate detection of the placement and migration patterns of proppants in fractures is crucial for unconventional oil and gas development, and its migration patterns are worth exploring, but most of the current research equipment in this area is invisible. The experimental devices in the existing technology cannot truly simulate the real shape of the fracture, and therefore cannot accurately explore the migration and accumulation patterns of proppants in rock fractures.

[0006] Therefore, how to provide a rock fracture model and a device and method for proppant migration and laying in rock fractures that can accurately predict the distribution pattern of proppant over time under precise fracture specifications, truly simulate the migration of proppant in fractures after unconventional reservoir fracturing, and provide a convenient observation is a problem that technicians in this field urgently need to solve. Summary of the invention

[0007] In view of this, the present invention provides a rock fracture model and a device and method for transporting and placing proppant in rock fractures, aiming to solve one of the problems in the above-mentioned background technology. It can accurately determine the distribution law of proppant over time under the fracture specifications, truly simulate the migration problem of proppant in the fracture after fracturing of unconventional reservoirs, and facilitate observation.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] A rock fracture model, comprising:

[0010] The rock model body is composed of two rocks, each of the rocks is provided with at least one rough surface, and the rough surfaces of the two rocks are combined to form a crack.

[0011] Furthermore, in the rock model body, at least one of the rocks is made of a transparent material, and the rough surface of the other rock is set as a light-absorbing surface, and the rough surface is made of frosted glass or an anti-glare coating is applied on the rough surface.

[0012] A proppant transport and paving device in rock fractures, comprising:

[0013] The support assembly includes a placing frame and a lifting frame, the rock model body is arranged on the placing frame, the bottom of the placing frame is connected to the lifting end of the lifting frame, the placing frame is provided with a plurality of through holes, each of the through holes passes through the placing frame, and each of the through holes is provided with an illuminating lamp;

[0014] A delivery assembly, comprising a mixer and a storage cylinder, wherein the mixer is connected to the storage cylinder through a pipeline, a stirrer is arranged in the mixer, a temperature regulator is arranged in the storage cylinder, the storage cylinder is connected to the crack through a delivery pipeline, a variable frequency delivery pump is arranged at one end of the delivery pipeline close to the storage cylinder, and a perfusion joint is arranged at the connection position between the delivery pipeline and the crack;

[0015] A gas flow controller is connected to the crack through a pipeline.

[0016] Furthermore, the monitoring component includes a flow meter, a pressure gauge and a thermometer, wherein the flow meter and the pressure gauge are both arranged on the conveying pipeline, the thermometer is arranged on the storage cylinder, and the pressure gauge is arranged at one end of the conveying pipeline close to the crack, and the flow meter is arranged at one end of the conveying pipeline close to the storage cylinder.

[0017] Furthermore, it also includes a data acquisition component, including a camera and a data acquisition instrument. The camera is arranged on both sides of the placement rack through a mounting plate. A plurality of cameras on the mounting plate are arranged at intervals in the vertical direction. The camera is signal-connected to the data acquisition instrument.

[0018] Furthermore, a transparent layer is detachably arranged on the placement rack, and the transparent layer covers the tops of all the through holes.

[0019] A method for transporting and placing proppant in rock fractures comprises the following steps:

[0020] Step 1: Make a rock crack model, fit the rough surfaces of two rocks together to form a crack, place the prepared rock crack model on a placement rack, and adjust the height of the placement rack through a support rack;

[0021] Step 2: Turn on the mixer, prepare the proppant in the mixer, transport the prepared proppant to the storage cylinder through the pipeline, and use the temperature regulator to adjust the temperature in the storage cylinder with the thermometer;

[0022] Step 3: Turn on the variable frequency delivery pump to deliver the proppant into the fracture through the delivery pipeline. The injection rate of the proppant is controlled by the variable frequency delivery pump in conjunction with the flow meter. At the same time, turn on the gas flow controller to intervene in the air in the fracture while injecting the proppant, thereby reducing the impact of the injected air on the flow field in the fracture.

[0023] Step 4: Turn on the lighting to illuminate, use the camera to collect data when the proppant enters the crack and moves, and upload the collected data to the data acquisition instrument for storage and analysis;

[0024] Step 5: After the experiment is completed, remove the transparent layer for cleaning, inject water into the cracks, and drain the proppant in the cracks.

[0025] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a rock fracture model and a device and method for transporting and placing proppant in rock fractures. By setting the rock fracture model, the real form of the fracture can be truly simulated, making it more convenient for experimenters to observe the migration and distribution law of the proppant mixture in the rock fracture inside the simulated core block from the outside;

[0026] By setting up lighting, the rock fracture model can be illuminated, and with transparent rocks and light-absorbing rocks, the distribution of proppants in the rock fractures can be made clearer.

[0027] By arranging multiple cameras around the placement rack, the distribution image of proppant migration in the rock fracture model can be collected from multiple positions, and then stored and analyzed by a data analyzer.

[0028] Through the method of proppant migration and placement in rock fractures, the distribution law of proppant over time can be accurately determined under the fracture specifications, and the migration problem of proppant in fractures after unconventional reservoir fracturing can be truly simulated. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0030] Figure 1 A schematic diagram of the structure of the device for transporting and placing proppant in rock fractures provided by the present invention;

[0031] Figure 2 A schematic diagram of the structure of the placement rack and the lifting rack provided by the present invention;

[0032] Figure 3 A schematic diagram of the structure of a camera arranged above the placement rack provided by the present invention;

[0033] Figure 4 The present invention is a schematic flow chart of the method for transporting and placing proppant in rock fractures provided by the present invention.

[0034] Among them: 1 is a placement rack; 2 is a lifting rack; 3 is a through hole; 4 is a lighting lamp; 5 is a mixer; 6 is a storage cylinder; 7 is a pipeline; 8 is a blender; 9 is a temperature regulator; 10 is a delivery pipeline; 11 is a flow meter; 12 is a pressure gauge; 13 is a thermometer; 14 is a camera; 15 is a mounting plate; 16 is a rock model body. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] See also Figure 1-4 , the embodiment of the present invention discloses

[0037] A rock fracture model, comprising:

[0038] The rock model body 16 is composed of two rocks, each of which is provided with at least one rough surface, and the rough surfaces of the two rocks are combined to form a crack.

[0039] In this embodiment, at least one of the rocks in the rock model body 16 is made of a transparent material, and the rough surface of the other rock is set as a light-absorbing surface. The rough surface is made of frosted glass or an anti-glare coating is applied to the rough surface. By setting one rock to be transparent and the rough surface of the other rock to be a light-absorbing surface, it is possible to more clearly observe the information when the proppant enters the crack and moves, while reducing the influence of the lighting lamp 4 on the observation.

[0040] A proppant transport and paving device in rock fractures, comprising:

[0041] The support assembly includes a placing frame 1 and a lifting frame 2. The rock model body 16 is arranged on the placing frame 1. The bottom of the placing frame 1 is connected to the lifting end of the lifting frame 2. The placing frame 1 is provided with a plurality of through holes 3. Each through hole 3 runs through the placing frame 1. Each through hole 3 is provided with an illuminating lamp 4. The rock model body 16 is placed and supported by the placing frame 1. The height is adjusted by the lifting frame 2 so that the conveying pipeline 10 and the crack position where the proppant is injected are at the same horizontal plane to avoid affecting the proppant injection rate. The illuminating lamp 4 is arranged in the through hole 3 to illuminate the crack on the placing frame 1.

[0042] The conveying assembly includes a mixer 5 and a storage barrel 6. The mixer 5 is connected to the storage barrel 6 through a pipeline 7. A stirrer 8 is provided in the mixer 5. A temperature regulator 9 is provided in the storage barrel 6. The storage barrel 6 is connected to the crack through a conveying pipeline 10. A variable frequency conveying pump is provided at one end of the conveying pipeline 10 close to the storage barrel 6. A perfusion joint is provided at the connection position between the conveying pipeline 10 and the crack. The conveying assembly is used to pump the proppant into the crack of the rock crack model and can control the injection rate of the proppant. A valve is provided on the conveying pipeline 10.

[0043] A gas flow controller is connected to the fracture through a pipeline; the gas flow controller can intervene in the air in the fracture while injecting the proppant, thereby reducing the influence of the injected air on the flow field in the fracture.

[0044] In this embodiment, the monitoring component includes a flow meter 11, a pressure gauge 12 and a thermometer 13. The flow meter 11 and the pressure gauge 12 are both arranged on the conveying pipeline 10, and the thermometer 13 is arranged on the storage cylinder 6. The pressure gauge 12 is arranged at one end of the conveying pipeline 10 close to the crack, and the flow meter 11 is arranged at one end of the conveying pipeline 10 close to the storage cylinder 6. The injection rate of the proppant is controlled by the variable frequency conveying pump in conjunction with the flow meter 11. The pressure on the conveying pipeline 10 is adjusted by the pressure gauge 12 in conjunction with the valve. The temperature regulator 9 cooperates with the thermometer 13 to adjust the temperature in the storage cylinder 6.

[0045] In this embodiment, a data acquisition component is also included, including a camera 14 and a data acquisition instrument. The camera 14 is arranged on both sides of the placement frame 1 through a mounting plate 15. A plurality of cameras 14 on the mounting plate 15 are arranged at intervals in the vertical direction, and the camera 14 is connected to the data acquisition instrument by signal. The camera 14 is arranged to collect data when the proppant enters the crack and moves, and the collected data is uploaded to the data acquisition instrument for storage and analysis through the camera 14.

[0046] In this embodiment, a transparent layer is detachably arranged on the placement rack 1, and the transparent layer covers the top of all the through holes 3; by setting the transparent layer, when moving in the proppant cracks, the proppant is prevented from falling randomly, polluting the lighting lamp 4 and affecting the lighting effect; the transparent layer is detachably arranged for easy cleaning and replacement.

[0047] In the case of poor lighting conditions, a placement plate is arranged between the two mounting plates 15, and a plurality of cameras 14 and lighting lamps 4 are arranged at intervals at the bottom of the placement plate, which can provide better lighting and better data collection.

[0048] A method for transporting and placing proppant in rock fractures comprises the following steps:

[0049] Step 1: Make a rock crack model, fit the rough surfaces of two rocks together to form a crack, place the prepared rock crack model on the placement rack 1, and adjust the height of the placement rack 1 through the support frame;

[0050] Step 2: Start the stirrer 8, prepare the proppant in the mixer 5, transport the prepared proppant to the storage cylinder 6 through the pipeline 7, and adjust the temperature in the storage cylinder 6 with the thermometer 13 using the temperature regulator 9;

[0051] Step 3: Turn on the variable frequency delivery pump to deliver the proppant into the fracture through the delivery pipe 10, control the injection rate of the proppant through the variable frequency delivery pump in conjunction with the flow meter 11, and turn on the gas flow controller at the same time to intervene in the air in the fracture while injecting the proppant, thereby reducing the impact of the injected air on the flow field in the fracture;

[0052] Step 4: Turn on the lighting lamp 4 for lighting, collect data through the camera 14 when the proppant enters the crack and moves, and upload the collected data to the data acquisition instrument for storage and analysis;

[0053] Step 5: After the experiment is completed, remove the transparent layer for cleaning, inject water into the cracks, and drain the proppant in the cracks.

[0054] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0055] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A rock fracture model, characterized in that: include: The rock model body is composed of two rocks, each of the rocks is provided with at least one rough surface, and the rough surfaces of the two rocks are combined to form a crack.

2. A rock fracture model according to claim 1, characterized in that: At least one of the rocks in the rock model body is made of a transparent material, and the rough surface of the other rock is set as a light-absorbing surface, and the rough surface is made of frosted glass or an anti-glare coating is applied on the rough surface.

3. A proppant transport and placement device in rock fractures, characterized in that: include: The support assembly includes a placing frame and a lifting frame, the rock model body is arranged on the placing frame, the bottom of the placing frame is connected to the lifting end of the lifting frame, the placing frame is provided with a plurality of through holes, each of the through holes passes through the placing frame, and each of the through holes is provided with an illuminating lamp; A delivery assembly, comprising a mixer and a storage cylinder, wherein the mixer is connected to the storage cylinder through a pipeline, a stirrer is arranged in the mixer, a temperature regulator is arranged in the storage cylinder, the storage cylinder is connected to the crack through a delivery pipeline, a variable frequency delivery pump is arranged at one end of the delivery pipeline close to the storage cylinder, and a perfusion joint is arranged at the connection position between the delivery pipeline and the crack; A gas flow controller is connected to the crack through a pipeline.

4. A proppant transport and placement device in rock fractures according to claim 3, characterized in that: The monitoring component includes a flow meter, a pressure gauge and a thermometer. The flow meter and the pressure gauge are both arranged on the conveying pipeline. The thermometer is arranged on the storage cylinder. The pressure gauge is arranged at one end of the conveying pipeline close to the crack. The flow meter is arranged at one end of the conveying pipeline close to the storage cylinder.

5. The device for transporting and placing proppant in rock fractures according to claim 3, characterized in that: It also includes a data acquisition component, including a camera and a data acquisition instrument. The camera is arranged on both sides of the placement rack through a mounting plate. A plurality of cameras on the mounting plate are arranged at intervals in the vertical direction. The camera is connected to the data acquisition instrument by signal.

6. The device for transporting and placing proppant in rock fractures according to claim 3, characterized in that: A transparent layer is detachably arranged on the placement rack, and covers the tops of all the through holes.

7. A method for transporting and placing proppant in rock fractures, characterized in that: The following steps are involved: Step 1: Make a rock crack model, fit the rough surfaces of two rocks together to form a crack, place the prepared rock crack model on a placement rack, and adjust the height of the placement rack through a support rack; Step 2: Turn on the mixer, prepare the proppant in the mixer, transport the prepared proppant to the storage cylinder through the pipeline, and use the temperature regulator to adjust the temperature in the storage cylinder with the thermometer; Step 3: Turn on the variable frequency delivery pump to deliver the proppant into the fracture through the delivery pipeline. The injection rate of the proppant is controlled by the variable frequency delivery pump in conjunction with the flow meter. At the same time, turn on the gas flow controller to intervene in the air in the fracture while injecting the proppant, thereby reducing the impact of the injected air on the flow field in the fracture. Step 4: Turn on the lighting to illuminate, use the camera to collect data when the proppant enters the crack and moves, and upload the collected data to the data acquisition instrument for storage and analysis; Step 5: After the experiment is completed, remove the transparent layer for cleaning, inject water into the cracks, and drain the proppant in the cracks.

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