An apparatus to simulate the effects of methane hydrates on drilling operations during drilling operations

Abstract

The application discloses a device for simulating the influence of methane hydrate on a drilling process in the drilling process, which comprises a simulated wellbore, a gas injection assembly, a drilling tool assembly, a drilling fluid circulating mechanism and a temperature control member; the drilling tool assembly comprises a drill pipe, a rotating driving member and a torque detection member; the drilling fluid circulating mechanism comprises an injection pipe, an injection pump, a circulating pump, a discharge pipe and a viscosity detection member; and the temperature control member is used for controlling the temperature of the drilling fluid in the injection pipe. The device has the beneficial effect that the torque value detected by the torque detection member can obtain the generation amount of the methane hydrate; meanwhile, the formed methane hydrate can be circulated with the drilling fluid to the discharge pipe and the injection pipe, so that the viscosity of the drilling fluid changes; the viscosity of the drilling fluid in the discharge pipe is detected by the viscosity detection member, so that the relationship between the viscosity of the drilling fluid and the generation amount of the methane hydrate can be obtained, and then the influence of the generation of the methane hydrate on the drilling process under the condition of the drilling fluid circulation can be obtained.

Description

Technical Field

[0001] This invention relates to the field of drilling technology, and in particular to an apparatus for simulating the effect of methane hydrates on the drilling process. Background Technology

[0002] During drilling with circulating drilling fluid, heat exchange occurs continuously between the drilling fluid and the formation. When drilling into hydrate-bearing formations, this heat exchange disrupts the stable environment of the hydrates, leading to their decomposition. The large amount of gas generated during decomposition, flowing with the drilling fluid, may undergo phase changes and form hydrates. Both the formation and decomposition of natural gas hydrates jeopardize the safety of deepwater drilling.

[0003] Due to the low temperature and high pressure conditions of deep water, solid hydrates are easily formed in the drilling fluid circulation channels, causing blockages inside drilling tools and between the drill bit or drill string and the wellbore. This can lead to major drilling safety accidents such as changes in drilling fluid properties, differential pressure stuck pipe, and abnormal pressure. In severe cases, drilling operations can be interrupted for 1 to 2 weeks, resulting in huge economic losses. Therefore, it is necessary to develop a device that can simulate the formation of methane hydrates during drilling and their impact on the drilling process.

[0004] Currently, the most commonly used methods for detecting hydrate formation mainly focus on the study of hydrates in static experimental devices (such as Chinese invention patent application number CN202011033596.7). Static experimental devices are widely used by natural gas hydrate research institutions due to their simple structure, convenient operation, and low cost. Existing hydrate formation evaluation devices are often designed to evaluate hydrate formation under static conditions. At most, they involve setting a stirring rod in a sealed body to simulate the agitation of drilling fluid and test hydrate formation in the drilling fluid. However, this cannot fully simulate the circulation of drilling fluid within the drilling tool, leading to simulation results that do not match actual drilling conditions. Summary of the Invention

[0005] In view of this, it is necessary to provide an apparatus for simulating the effect of methane hydrates on the drilling process, which can simulate the formation of methane hydrates and their impact on the drilling process under drilling fluid circulation conditions.

[0006] To achieve the above objectives, the present invention provides an apparatus for simulating the effect of methane hydrate on the drilling process, including a simulated wellbore, a gas injection assembly, a drill string assembly, a drilling fluid circulation mechanism, and a temperature control component.

[0007] The simulated wellbore has a sealed wellbore cavity;

[0008] The gas injection assembly is used to inject methane into the wellbore cavity;

[0009] The drilling tool assembly comprises a drill pipe, a rotary drive and a torque detection element, the drill pipe is arranged in the wellbore cavity, the rotary drive is connected with the drill pipe and is used to drive the drill pipe to rotate, and the torque detection element is connected with the rotary drive and is used to detect the torque when the drill pipe rotates.

[0010] The drilling fluid circulation mechanism comprises an injection pipe, an injection pump, a circulation pump, a discharge pipe and a viscosity detection element, the first end of the injection pipe is communicated with the outlet of the injection pump, the second end of the injection pipe is communicated with the wellbore cavity, the circulation pump is arranged on the injection pipe, one end of the discharge pipe is communicated with the wellbore cavity, the other end of the discharge pipe is communicated with the first end of the injection pipe, and the viscosity detection element is used to detect the viscosity of the drilling fluid in the discharge pipe.

[0011] The temperature control element is used to control the temperature of the drilling fluid in the injection pipe.

[0012] In some embodiments, the rotary drive is a rotary motor, the rotary motor is connected with the drill pipe and is used to drive the drill pipe to rotate, and the torque detection element is a torque sensor, the torque sensor is electrically connected with the rotary motor and is used to detect the output torque of the rotary motor.

[0013] In some embodiments, the gas injection assembly comprises a gas cylinder, a gas inlet pipe, a gas inlet valve and a gas injection amount detector, the gas cylinder is used to store methane, one end of the gas inlet pipe is communicated with the gas cylinder, the other end of the gas inlet pipe is communicated with the wellbore cavity, the gas inlet valve is arranged on the gas inlet pipe, and the gas injection amount detector is arranged on the gas inlet pipe.

[0014] In some embodiments, the side wall of the simulated wellbore is provided with an observation window.

[0015] In some embodiments, the injection pipe is provided with a first pressure detection element, the first pressure detection element is used to detect the pressure of the drilling fluid in the injection pipe, the discharge pipe is provided with a second pressure detection element, and the second pressure detection element is used to detect the pressure of the drilling fluid in the discharge pipe.

[0016] In some embodiments, the injection pipe is provided with a flow detection element, and the flow detection element is used to detect the flow of the drilling fluid in the injection pipe.

[0017] In some embodiments, the discharge pipe is provided with a solution resistance detection element, and the solution resistance detection element is used to detect the resistance of the drilling fluid in the discharge pipe.

[0018] In some embodiments, the discharge pipe is provided with an ultrasonic hydrate detection element, and the ultrasonic hydrate detection element is used to detect the content of the methane hydrate in the discharge pipe.

[0019] In some embodiments, the device for simulating the influence of methane hydrate on the drilling process in the drilling process further comprises a dissolved gas metering assembly, the dissolved gas metering assembly comprises a sampling pipe, two sampling valves, a gas exhaust valve and a gas volume detection piece, both ends of the sampling pipe are communicated with the discharge pipe, the two sampling valves are arranged at both ends of the sampling pipe respectively, the gas exhaust valve is arranged on the sampling pipe and between the two sampling valves, and the gas volume detection piece is communicated with the outlet of the gas exhaust valve.

[0020] In some embodiments, the temperature control piece is wrapped on the injection pipe.

[0021] Compared with the prior art, the technical scheme has the beneficial effects that: in use, the drilling fluid is injected into the injection pipe by the injection pump, the drilling fluid enters the drill pipe from the injection pipe, and then is discharged from the lower end of the drill pipe into the wellbore cavity, and then the drilling fluid enters the discharge pipe from the wellbore cavity, and then enters the injection pipe from the discharge pipe, thereby forming a circulation, and the function of the circulation pump is to provide power for the circulation of the drilling fluid, in the process of circulation of the drilling fluid, the temperature control piece can reduce the temperature of the drilling fluid to a preset temperature, thereby simulating the temperature in the deep sea drilling, the rotating driving piece drives the drill pipe to rotate to simulate the real drilling process, the gas injection assembly injects a certain amount of methane gas into the wellbore cavity, the methane gas combines with water to form methane hydrate solid under the condition of low temperature and high pressure, when the methane hydrate solid is formed, the torque in the process of rotation of the drill pipe will increase, so that the amount of generation of the methane hydrate can be obtained by the torque value detected by the torque detection piece, at the same time, the formed methane hydrate will circulate with the drilling fluid into the discharge pipe and the injection pipe, thereby causing the viscosity of the drilling fluid to change, the viscosity of the drilling fluid in the discharge pipe is detected by the viscosity detection piece, so that the relationship between the viscosity of the drilling fluid and the amount of generation of the methane hydrate can be obtained, and then the influence of the generation of the methane hydrate on the drilling process under the condition of circulation of the drilling fluid can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a structural schematic view of an embodiment of the device for simulating the influence of methane hydrate on the drilling process in the drilling process provided by the application;

[0023] In the diagram: 1-Simulated wellbore, 11-Observation window, 2-Injection assembly, 21-Gas cylinder, 22-Inlet pipe, 23-Inlet valve, 24-Inlet volume detector, 3-Drilling tool assembly, 31-Drill pipe, 32-Rotation drive, 33-Torque detector, 4-Drilling fluid circulation mechanism, 41-Injection pipe, 42-Injection pump, 43-Circulation pump, 44-Discharge pipe, 45-Viscosity detector, 46-First pressure detector, 47-Second pressure detector, 48-Flow rate detector, 49-Solution resistance detector, 410-Ultrasonic hydrate detector, 5-Temperature control unit, 6-Dissolved gas metering assembly, 61-Sampling pipe, 62-Sampling valve, 63-Exhaust valve, 64-Gas volume detector, 7-Raman spectrometer. Detailed Implementation

[0024] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0025] Please refer to Figure 1 The present invention provides an apparatus for simulating the effect of methane hydrate on the drilling process, including a simulated wellbore 1, an injection assembly 2, a drill string assembly 3, a drilling fluid circulation mechanism 4, and a temperature control component 5.

[0026] The simulated wellbore 1 has a sealed wellbore cavity. The gas injection assembly 2 is used to inject methane into the wellbore cavity.

[0027] The drill assembly 3 includes a drill pipe 31, a rotation drive 32, and a torque detection element 33. The drill pipe 31 is disposed inside the wellbore cavity. The rotation drive 32 is connected to the drill pipe 31 and is used to drive the drill pipe 31 to rotate. The torque detection element 33 is connected to the rotation drive and is used to detect the torque of the drill pipe 31 when it rotates.

[0028] The drilling fluid circulation mechanism 4 includes an injection pipe 41, an injection pump 42, a circulation pump 43, a discharge pipe 44, and a viscosity detection element 45. The first end of the injection pipe 41 is connected to the outlet of the injection pump 42, and the second end of the injection pipe 41 is connected to the wellbore cavity. The circulation pump 43 is mounted on the injection pipe 41. One end of the discharge pipe 44 is connected to the wellbore cavity (in this embodiment, one end of the discharge pipe 44 is connected to the wellbore cavity via the drill pipe 31), and the other end of the discharge pipe 44 is connected to the first end of the injection pipe 41. The viscosity detection element 45 is used to detect the viscosity of the drilling fluid in the discharge pipe 44. The temperature control element 5 is used to control the temperature of the drilling fluid in the injection pipe 41.

[0029] In use, drilling fluid is injected into the injection pipe 41 by the injection pump 42, and the drilling fluid enters the drill pipe 31 from the injection pipe 41, and is discharged into the wellbore cavity from the lower end of the drill pipe 31, and then the drilling fluid enters the discharge pipe 44 from the wellbore cavity, and then enters the injection pipe 41 from the discharge pipe 44, thereby forming a circulation, and the circulation pump 43 provides power for the circulation of the drilling fluid, and the temperature control member 5 can reduce the temperature of the drilling fluid to a preset temperature during the circulation of the drilling fluid, thereby simulating the temperature during deep-sea drilling, and the rotary drive member 32 drives the drill pipe 31 to rotate to simulate the actual drilling process, and the gas injection assembly 2 injects a certain amount of methane gas into the wellbore cavity, and the methane gas combines with water under the condition of low temperature and high pressure to form methane hydrate solid, and when the methane hydrate solid is formed, the torque during the rotation of the drill pipe 31 will increase, so that the amount of methane hydrate generated can be obtained by the torque value detected by the torque detection member 33, and at the same time, the formed methane hydrate will circulate with the drilling fluid into the discharge pipe 44 and the injection pipe 41, thereby causing the viscosity of the drilling fluid to change, and the viscosity of the drilling fluid in the discharge pipe 44 is detected by the viscosity detection member 45, thereby obtaining the relationship between the viscosity of the drilling fluid and the amount of methane hydrate generated, and further obtaining the influence of the generation of methane hydrate on the drilling process under the condition of the circulation of the drilling fluid.

[0030] To realize the function of the torque detection member 33, please refer to Figure 1 In a preferred embodiment, the rotary drive member 32 is a rotary motor connected with the drill pipe 31 and used to drive the drill pipe 31 to rotate, and the torque detection member 33 is a torque sensor electrically connected with the rotary motor and used to detect the output torque of the rotary motor.

[0031] To realize the function of the gas injection assembly 2, please refer to Figure 1 In a preferred embodiment, the gas injection assembly 2 includes a gas cylinder 21, an air inlet pipe 22, an air inlet valve 23, and an air inlet amount detector 24, the gas cylinder 21 is used to store methane, one end of the air inlet pipe 22 is in communication with the gas cylinder 21, the other end of the air inlet pipe 22 is in communication with the wellbore cavity, the air inlet valve 23 is arranged on the air inlet pipe 22, and the air inlet amount detector 24 is arranged on the air inlet pipe 22, in use, the total amount of methane gas injected into the wellbore cavity can be controlled by the air inlet amount detector 24, thereby determining the relationship between the total amount of injected methane gas and the amount of methane hydrate generated through multiple experiments.

[0032] To facilitate the visual observation of the generation process of natural gas hydrate, please refer to Figure 1 In a preferred embodiment, an observation window 11 is arranged on the side wall of the simulated wellbore 1.

[0033] For the convenience of determining the influence of the generation of methane hydrate on the circulating pressure of drilling fluid, please refer to Figure 1 In a preferred embodiment, the injection pipe 41 is provided with a first pressure detecting member 46 for detecting the pressure of drilling fluid in the injection pipe 41, and the discharge pipe 44 is provided with a second pressure detecting member 47 for detecting the pressure of drilling fluid in the discharge pipe 44. In use, the pressure of drilling fluid in the circulating process is determined by the first pressure detecting member 46 and the second pressure detecting member 47, so that the relationship between the pressure of drilling fluid and the generation amount of methane hydrate is obtained, and then the influence of the generation of methane hydrate on the pressure of drilling fluid in the drilling process under the condition of circulating drilling fluid is obtained. It should be understood that in this process, the circulating pump 43 always has a constant power output, so as to avoid the change of the pressure of drilling fluid caused by the change of the output power of the circulating pump 43.

[0034] For the convenience of determining the influence of the generation of methane hydrate on the flow rate of drilling fluid, please refer to Figure 1 In a preferred embodiment, the injection pipe 41 is provided with a flow rate detecting member 48 for detecting the flow rate of drilling fluid in the injection pipe 41. In use, the flow rate of drilling fluid in the injection pipe 41 is detected by the flow rate detecting member 48, so that the relationship between the flow rate of drilling fluid and the generation amount of methane hydrate is obtained, and then the influence of the generation of methane hydrate on the flow rate of drilling fluid in the drilling process under the condition of circulating drilling fluid is obtained.

[0035] For the convenience of more accurately calculating the generation amount of methane hydrate, please refer to Figure 1 In a preferred embodiment, the discharge pipe 44 is provided with a solution resistance detecting member 49 for detecting the resistance of drilling fluid in the discharge pipe 44, so that the generation amount of methane hydrate is calculated by the resistance of drilling fluid, and compared with the generation amount of methane hydrate calculated by torque, so as to improve the accuracy of the result.

[0036] For the convenience of more accurately calculating the generation amount of methane hydrate, please refer to Figure 1 In a preferred embodiment, the discharge pipe 44 is provided with an ultrasonic hydrate detecting member 410 for detecting the content of methane hydrate in the discharge pipe 44. In use, the content of methane hydrate in the discharge pipe 44 is detected by the ultrasonic hydrate detecting member 410, and the generation amount of methane hydrate in the whole system is calculated according to the proportion, and compared with the generation amount of methane hydrate calculated by torque, so as to improve the accuracy of the result.

[0037] For the convenience of more accurately calculating the amount of the generated methane hydrate, please refer to Figure 1 In a preferred embodiment, the device for simulating the influence of the methane hydrate on the drilling process further comprises a dissolved gas metering assembly 6, which comprises a sampling pipe 61, two sampling valves 62, a vent valve 63 and a gas volume detecting element 64, both ends of the sampling pipe 61 are communicated with the discharge pipe 44, the two sampling valves 62 are respectively arranged at both ends of the sampling pipe 61, the vent valve 63 is arranged on the sampling pipe 61 and located between the two sampling valves 62, and the gas volume detecting element 64 is communicated with the outlet of the vent valve 63. In use, when the amount of the generated methane hydrate needs to be calculated, the two sampling valves 62 are closed, and then the vent valve 63 is opened, the vent valve 63 is communicated with the gas volume detecting element 64, so that when the vent valve 63 is opened, the pressure in the sampling pipe 61 rapidly decreases, so that the methane hydrate in the sampling pipe 61 is decomposed into methane gas and discharged from the vent valve 63 to the gas volume detecting element 64, the volume of the discharged gas is detected by the gas volume detecting element 64, so that the amount of the methane hydrate in the sampling pipe 61 is converted, and the amount of the generated methane hydrate in the whole system is converted in proportion, and is compared with the amount of the generated methane hydrate calculated by the torque, so as to improve the accuracy of the result.

[0038] For the convenience of more accurately calculating the amount of the generated methane hydrate, please refer to Figure 1 In a preferred embodiment, the device for simulating the influence of the methane hydrate on the drilling process further comprises a Raman spectrum tester 7, which is used to measure the amount of the generated methane hydrate in the sampling pipe 61, and the result is compared with the amount of the generated methane hydrate calculated by the torque, so as to improve the accuracy of the result.

[0039] For the convenience of realizing the function of the temperature control element 5, please refer to Figure 1 In a preferred embodiment, the temperature control element 5 is coated on the injection pipe 41.

[0040] For the convenience of better understanding the present application, the following will be described in combination with Figure 1The working process of the device for simulating the influence of methane hydrate on the drilling process provided by the present application is described in detail as follows: in use, drilling fluid is injected into the injection pipe 41 through the injection pump 42, the drilling fluid enters the drill pipe 31 from the injection pipe 41, and then is discharged into the wellbore cavity from the lower end of the drill pipe 31, after which the drilling fluid enters the discharge pipe 44 from the wellbore cavity, and then enters the injection pipe 41 from the discharge pipe 44, thereby forming a circulation, and the circulation pump 43 provides power for the circulation of the drilling fluid, in the process of circulation of the drilling fluid, the temperature control member 5 can reduce the temperature of the drilling fluid to a preset temperature, thereby simulating the temperature in deep-sea drilling, the rotary drive member 32 drives the drill pipe 31 to rotate to simulate the real drilling process, the gas injection assembly 2 injects a certain amount of methane gas into the wellbore cavity, and the methane gas combines with water to form methane hydrate solid under the condition of low temperature and high pressure, when the methane hydrate solid is formed, the torque during the rotation of the drill pipe 31 will increase, so that the amount of methane hydrate generated can be obtained through the torque value detected by the torque detection member 33, and the amount of methane hydrate generated is calculated through the solution resistance detection member 49, the ultrasonic hydrate detection member 410, the gas volume detection member 64, and the Raman spectrum tester 7, and the results are compared to improve the accuracy of the results; the formed methane hydrate will circulate with the drilling fluid into the discharge pipe 44 and the injection pipe 41, thereby causing changes in the viscosity, pressure, flow rate, etc. of the drilling fluid, the viscosity of the drilling fluid in the discharge pipe 44 is detected through the viscosity detection member 45, so that the relationship between the viscosity of the drilling fluid and the amount of methane hydrate generated can be obtained, the pressure in the process of circulation of the drilling fluid is determined through the first pressure detection member 46 and the second pressure detection member 47, so that the relationship between the pressure of the drilling fluid and the amount of methane hydrate generated can be obtained, the flow rate of the drilling fluid in the injection pipe 41 is detected through the flow rate detection member 48, so that the relationship between the flow rate of the drilling fluid and the amount of methane hydrate generated can be obtained, and then the influence of the generation of methane hydrate on the drilling process under the condition of circulation of the drilling fluid is obtained.

[0041] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any changes or replacements easily thought of by those skilled in the art within the technical scope disclosed by the present application shall be covered within the protection scope of the present application.

Claims

1. An apparatus for simulating the effect of methane hydrates on the drilling process, characterized in that, This includes a simulated wellbore, gas injection components, drill string components, drilling fluid circulation mechanism, and temperature control components. The simulated wellbore has a sealed wellbore cavity; The gas injection assembly is used to inject methane into the wellbore cavity; The drilling tool assembly includes a drill pipe, a rotation drive, and a torque detection device. The drill pipe is disposed inside the wellbore cavity. The rotation drive is connected to the drill pipe and is used to drive the drill pipe to rotate. The torque detection device is connected to the rotation drive and is used to detect the torque when the drill pipe rotates. The drilling fluid circulation mechanism includes an injection pipe, an injection pump, a circulation pump, a discharge pipe, and a viscosity measuring device. The first end of the injection pipe is connected to the outlet of the injection pump, and the second end of the injection pipe is connected to the wellbore cavity. The circulation pump is mounted on the injection pipe. One end of the discharge pipe is connected to the wellbore cavity, and the other end of the discharge pipe is connected to the first end of the injection pipe. The viscosity measuring device is used to detect the viscosity of the drilling fluid in the discharge pipe. The temperature control component is used to control the temperature of the drilling fluid in the injection pipe; An ultrasonic hydrate detector is installed on the discharge pipe, which is used to detect the content of methane hydrate in the discharge pipe; The device for simulating the impact of methane hydrate on the drilling process also includes a dissolved gas metering component. The dissolved gas metering component includes a sampling tube, two sampling valves, an exhaust valve, and a gas volume detection device. Both ends of the sampling tube are connected to the exhaust tube. The two sampling valves are respectively located at both ends of the sampling tube. The exhaust valve is located on the sampling tube and between the two sampling valves. The gas volume detection device is connected to the outlet of the exhaust valve.

2. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The rotation drive component is a rotary motor, which is connected to the drill rod and is used to drive the drill rod to rotate. The torque detection component is a torque sensor, which is electrically connected to the rotating motor and used to detect the output torque of the rotating motor.

3. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The gas injection assembly includes a gas cylinder, an inlet pipe, an inlet valve, and an inlet volume detector. The gas cylinder is used to store methane. One end of the inlet pipe is connected to the gas cylinder, and the other end of the inlet pipe is connected to the wellbore cavity. The inlet valve is located on the inlet pipe, and the inlet volume detector is located on the inlet pipe.

4. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The simulated wellbore has an observation window on its side wall.

5. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The injection pipe is equipped with a first pressure detection element, which is used to detect the pressure of the drilling fluid in the injection pipe. A second pressure detection element is provided on the discharge pipe, which is used to detect the pressure of the drilling fluid in the discharge pipe.

6. The apparatus for simulating the effect of methane hydrates on the drilling process according to claim 1, characterized in that, The injection pipe is equipped with a flow detection device, which is used to detect the flow rate of drilling fluid in the injection pipe.

7. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The discharge pipe is equipped with a solution resistance detector, which is used to detect the resistance of the drilling fluid in the discharge pipe.

8. The apparatus for simulating the effect of methane hydrate on the drilling process according to claim 1, characterized in that, The temperature control element is covered on the injection tube.

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