CN112031761A - Blockage removing device and method for simulating gas well hydrate blockage - Google Patents

Abstract

The invention relates to a plugging removal device and method for simulating gas well hydrate plugging. The device consists of a liquid injection system, a gas injection system, a blocking removal system and a data acquisition and analysis system. The liquid injection system includes a water tank, an injection pump, and a liquid flow meter. The blockage removal system includes simulated wellbore, pressure sensor group, temperature sensor group, visual window, perforated pallet, incubator and camera, and the data acquisition and analysis system includes computer and control cabinet. The method includes: setting the temperature of the thermostat to be the temperature required for the experiment, and setting the outlet pressure of the pressure regulating valve; injecting methane gas into the simulated wellbore; The camera records the hydrate decomposition process, and the computer collects data such as temperature and pressure. The invention simulates the production conditions of the gas well and wellbore by setting the experimental parameters, so as to provide a strong guarantee for the on-site gas well wellbore hydrate blockage removal construction.

Description

A plugging removal device and method for simulating gas well hydrate plugging

technical field

The invention relates to a device and method for unblocking gas wells in the process of oil and gas exploration and development, in particular to a device and method for unblocking gas wells for simulating gas well hydrate blockage.

Background technique

Natural gas hydrate is a non-stoichiometric cage-like crystal material generated by water and natural gas under high pressure and low temperature environment. It is an unconventional energy source with high density and high calorific value, mainly distributed in marine and terrestrial permafrost sediments. , natural gas hydrate is generally considered to be the most potential replacement energy in the 21st century, and it is also a new energy with the largest reserves that has not yet been developed.

In the process of gas well production, due to the constant changes of wellbore temperature and high pressure, it is very easy to meet the hydrate formation conditions in some parts of the wellbore. Once the hydrate is formed in the wellbore, it is easy to deposit and adhere to the inner wall of the wellbore, causing flow obstruction, and even blocking the wellbore, so that the formation fluid cannot be transported to the surface through the wellbore production, which will seriously affect the normal production of gas wells and cause serious economic losses. , the control of hydrate blockage in gas wells is very complicated, time-consuming and expensive. This problem has become an important factor affecting the production safety of gas wells, restricting the process of efficient gas field development, and has attracted extensive attention from scholars and operators at home and abroad. At present, the change rules of hydrate decomposition amount, decomposition rate and plug removal time in the process of plugging removal in gas wells are unclear, and the changing laws of wellbore temperature field and pressure field and the economic dosage of plugging agents during plugging removal process are unknown. The plugging removal device and method for simulating gas well hydrate plugging are used to study the plugging removal law of gas wells.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a plugging removal device for simulating gas well hydrate plugging. The device is reliable in principle and easy to operate. By setting experimental parameters, the production conditions of gas well wellbore are simulated, so as to provide for on-site gas well wellbore hydrate plugging removal construction. Strong guarantee.

Another object of the present invention is to provide a plugging removal method for simulating gas well hydrate plugging by using the above-mentioned device, which can not only test the variation law of the wellbore temperature field and pressure field and the amount of plugging remover during the plugging removal process, but also test the amount of the plugging remover in the experimental process. Temperature, pressure, hydrate decomposition amount, decomposition rate and other parameters are monitored, collected and stored in real time.

In order to achieve the above technical purpose, the present invention adopts the following technical solutions.

A plugging removal device for simulating gas well hydrate plugging consists of a liquid injection system, a gas injection system, a plugging removal system and a data acquisition and analysis system.

The liquid injection system includes a water tank, a fifth valve, an injection pump, a liquid flow meter, a sixth valve and a water injection pipeline.

The gas injection system includes a gas injection pipeline, a gas flow meter, a first valve, a second valve, a third valve, an air compressor, a gas booster pump, a pressure regulating valve, a fourth valve and a methane gas cylinder.

The plugging removal system includes a simulated wellbore, a pressure sensor set, a sapphire viewing window, a solid plugging removal agent, a hydrate, a perforated support plate, methane gas, an incubator, a temperature sensor set, an upper sealing flange, a lower sealing flange and camera.

The data acquisition and analysis system includes a computer and a control cabinet.

Further, one end of the fifth valve is connected to the outlet of the water tank, the other end is connected to the injection pump, the injection pump is connected to the liquid flow meter, the other end of the liquid flow meter is connected to the sixth valve, and the sixth valve is injected with water. The pipeline is connected with the upper sealing flange, the upper sealing flange is connected with the simulated wellbore by thread, and the water injection pipeline is connected with the simulated wellbore through the upper sealing flange.

Further, one end of the fourth valve is connected to the methane cylinder, the other end is connected to the pressure regulating valve, the pressure regulating valve is connected to the gas booster pump, the gas booster pump is connected to the second valve, and the air compressor is connected to the second valve. The three valves are connected to the gas booster pump, the compressed air provided by the air compressor provides power for the gas booster pump to compress methane gas, the second valve is connected to the gas flowmeter, and the pipeline between the second valve and the gas flowmeter is connected to the third A valve is used for simulating gas discharge in the wellbore to facilitate pressure relief, the gas flow meter communicates with the lower sealing flange through the gas injection line, and the gas injection line communicates with the simulated wellbore through the lower sealing flange.

Further, the lower sealing flange is threadedly connected to the simulated wellbore, the perforated support plate is welded and fixed to the simulated wellbore, the hydrate is placed on the perforated support plate, and the solid blocking agent is placed on the hydrate. The sapphire viewing window is installed in the simulated wellbore, and the camera is installed in the incubator. Through the sapphire viewing window, the camera can shoot and observe the decomposition of hydrate in the simulated wellbore. The temperature sensor group and the pressure sensor group are evenly installed on the simulated wellbore. The temperature sensor group and the pressure sensor group are symmetrically distributed, the simulated wellbore is filled with methane gas, and the plug removal system is placed in a constant temperature box, which provides a temperature-controlled environment for the simulated wellbore.

Further, the computer is connected with a control cabinet, and the control cabinet is respectively connected with a pressure sensor group, a constant temperature box, a gas flowmeter, an air compressor, a water injection pump, a liquid flowmeter, a temperature sensor group and a camera.

The plugging removal method for simulating gas well hydrate plugging by using the above device includes the following steps in sequence:

(1) Set the temperature in the incubator to the temperature required for the experiment, fill the water tank with clean water, place the hydrate on the perforated support plate, and place the solid block remover on the hydrate, and set the pressure regulating valve. outlet pressure;

(2) The gas booster pump injects methane gas into the simulated wellbore through the gas injection pipeline, and stops the gas injection when the pressure in the simulated wellbore reaches the pressure required for the experiment;

(3) The water injection pump injects the clean water in the water tank into the simulated wellbore through the water injection pipeline, until the clean water in the simulated wellbore submerges the solid plugging release agent. Decomposition, the camera records the hydrate decomposition process, and the computer forms the temperature and pressure change curve during the plugging removal process according to the collected temperature, pressure and decomposition process images, and simultaneously obtains the hydrate decomposition amount, decomposition rate and solid plugging removal agent dosage, etc. data.

Compared with the prior art, the advantages of the present invention are:

(1) The plugging removal device and method can simulate the wellbore production conditions of gas wells, and then study the variation law of the hydrate decomposition amount, decomposition rate and plugging removal time in the plugged wellbore;

(2) The plugging removal device and method can simulate the variation law of wellbore temperature field and pressure field and the amount of plugging removal agent during the plugging removal process;

(3) The plugging removal device and method can perform real-time monitoring, collection and storage of parameters such as temperature, pressure, hydrate decomposition amount, and decomposition rate during the experiment, and can draw the change curve of each parameter.

Description of drawings

FIG. 1 is a schematic structural diagram of a plugging removal device for simulating gas well hydrate plugging.

In the picture: 1. Simulated wellbore, 2. Pressure sensor group, 3. Sapphire viewing window, 4. Solid blocking agent, 5. Hydrate, 6. Perforated plate, 7. Methane gas, 8. Gas injection line, 9. Constant temperature box, 10. Gas flow meter, 11. First valve, 12. Second valve, 13. Third valve, 14. Air compressor, 15. Gas booster pump, 16. Pressure regulating valve, 17. Fourth valve, 18. Water tank, 19. Fifth valve, 20. Injection pump, 21. Liquid flow meter, 22. Sixth valve, 23. Water injection line, 24. Temperature sensor group, 25. Methane gas cylinder, 26 .computer, 27. control cabinet, 28. upper sealing flange, 29. lower sealing flange, 30. camera.

Detailed ways

The present invention is further described below according to the accompanying drawings and examples, so as to facilitate the understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, they are protected within the scope of the present invention. List.

See Figure 1.

A plugging removal device for simulating gas well hydrate plugging consists of a liquid injection system, a gas injection system, a plugging removal system and a data acquisition and analysis system.

The liquid injection system includes a water tank 18, an injection pump 20, a liquid flow meter 21 and a water injection pipeline 23; the gas injection system includes a methane cylinder 25, a pressure regulating valve 16, a gas booster pump 15, an air compressor 14, The gas flow meter 10 and the gas injection pipeline 8; the plugging removal system includes a simulated wellbore 1, a pressure sensor group 2, a temperature sensor group 24, a sapphire viewing window 3, a perforated support plate 6, an incubator 9 and a camera 30, the simulated wellbore 1 is placed in an incubator 9, the upper and lower ends of the simulated wellbore 1 are connected with an upper sealing flange 28 and a lower sealing flange 29 by threads, a pressure sensor group 2 and a temperature sensor group 24 are installed in the simulated wellbore, and a sapphire can be embedded in the middle of the simulated wellbore. The viewing window 3, the viewing window 3 is facing the camera 30, a perforated supporting plate 6 is arranged in the simulated wellbore, and the perforated supporting plate 6 is placed with a hydrate 5 and a solid deblocking agent 4; The data acquisition and analysis system includes a computer 26 and Control cabinet 27.

The water tank 18 is connected to the water injection pump 20, and then connected to the upper sealing flange 28 of the simulated wellbore 1 through the water injection pipeline 23, and a liquid flow meter 21 is set on the water injection pipeline; the methane gas cylinder 25 is sequentially connected to the pressure regulating valve 16, the gas The booster pump 15 is connected to the lower sealing flange 29 of the simulated wellbore 1 through the gas injection line 8, the gas booster pump is connected to the air compressor 14, and the gas injection line is provided with a gas flow meter 10; Connect with pressure sensor group, temperature sensor group, incubator, gas flow meter, air compressor, injection pump, liquid flow meter and camera.

The clean water in the water tank 18 is injected into the simulated wellbore 1 through the water injection line 23 . After the clean water and the solid blocking agent 4 are in contact, the heat released by the solid blocking agent 4 gradually decomposes the hydrate 5 . The camera 30 observes through the sapphire viewing window 3 And record the whole process of hydrate decomposition.

Example

Preparation process: The experimental operator first issues a temperature control instruction through the computer 26 and the control cabinet 27, so that the temperature in the incubator 9 is set to the temperature required for the experiment, and the water tank 18 is filled with clean water of the required temperature for the experiment. The temperature is the same as that of the incubator 9 , then put the hydrate 5 on the perforated support plate 6 , the solid deblocking agent 4 on the hydrate 5 , and set the outlet pressure of the pressure regulating valve 16 .

Gas injection and pressure maintaining process: open the second valve 12, the third valve 13 and the fourth valve 17, then start the air compressor 14 through the computer 26, and the air compressor 14 drives the gas booster pump 15 through the gas injection line 8 to the simulated wellbore 1. Methane gas 7 is injected. The gas volume during the gas injection is measured by the gas flow meter 10. When the pressure in the simulated wellbore 1 reaches the pressure required for the experiment, the gas injection is stopped, and then the relevant valve is closed.

Liquid injection plugging process: open the fifth valve 19 and the sixth valve 22, start the injection pump 20 through the computer 26, and the injection pump 20 injects the clean water in the water tank 18 into the simulated wellbore 1 through the water injection pipeline 23, and into the simulated wellbore 1 The amount of clean water is measured by the liquid flow meter 21. When the clean water in the simulated wellbore 1 submerges the solid blocking remover 4, the water injection pump 20 is closed, and the relevant valves are closed at the same time. The blocking agent 4 starts to release heat. The solid blocking agent 4 is a new type of blocking agent that reacts with water to release heat. The heat released by the solid blocking agent 4 is transferred downward to the hydrate 5 and around the solid blocking agent 4. The heat released by the solid deblocking agent 4 gradually decomposes the hydrate. The camera 30 records the whole process of the hydrate decomposition. The experimental operator can observe the hydrate decomposition through the computer 26. After the hydrate is completely decomposed, inject liquid The unblocking process is complete. The temperature and pressure data collected in real time by the temperature sensor group 24 and the pressure sensor group 2 are uploaded to the computer 26 through the electronic control cabinet 27. After the computer is analyzed by the data analysis software, the temperature and pressure change curve during the plugging removal process is formed, and the decomposition amount of hydrate is obtained at the same time. , decomposition rate and the amount of solid plug remover and other data.

Subsequent cleaning process: open the first valve 11, discharge the waste liquid and waste gas in the simulated wellbore 1, and then inject clean water into the simulated wellbore 1 with the water injection pump 20 to clean the simulated wellbore, and the experiment ends.

All or part of the process in the method of the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. A flow of an embodiment of a method. Wherein, the storage medium may be a magnetic disk, an optical disk, a ROM, a RAM, and the like.

Claims (3)

1. A blockage removing device for simulating gas well hydrate blockage consists of a liquid injection system, a gas injection system, a blockage removing system and a data acquisition and analysis system, and is characterized in that the liquid injection system comprises a water tank (18), a water injection pump (20), a liquid flowmeter (21) and a water injection pipeline (23); the gas injection system comprises a methane gas cylinder (25), a pressure regulating valve (16), a gas booster pump (15), an air compressor (14), a gas flowmeter (10) and a gas injection pipeline (8); the blockage relieving system comprises a simulation shaft (1), a pressure sensor group (2), a temperature sensor group (24), a sapphire visible window (3), a perforated supporting plate (6), a thermostat (9) and a camera (30), wherein the simulation shaft is arranged in the thermostat, the upper end and the lower end of the simulation shaft are connected with an upper sealing flange (28) and a lower sealing flange (29) through threads, the simulation shaft is provided with the pressure sensor group and the temperature sensor group, the sapphire visible window is embedded in the middle of the simulation shaft, the visible window is opposite to the camera, the perforated supporting plate is arranged in the simulation shaft, and a hydrate (5) and a solid blockage relieving agent (4) are placed on the perforated supporting plate; the data acquisition and analysis system comprises a computer (26) and a control cabinet (27).

2. A blockage relieving device for simulating gas well hydrate blockage according to claim 1, wherein the water tank (18) is connected with a water injection pump (20) and then is connected with an upper sealing flange (28) of a simulated well bore through a water injection pipeline (23), and the water injection pipeline is provided with a liquid flow meter (21); the methane gas bottle (25) is sequentially connected with a pressure regulating valve (16) and a gas booster pump (15), and then is connected with a lower sealing flange (29) of the simulated shaft through a gas injection pipeline (8), the gas booster pump is connected with an air compressor (14), and the gas injection pipeline is provided with a gas flowmeter (10); and the computer is respectively connected with the pressure sensor group, the temperature sensor group, the constant temperature box, the gas flowmeter, the air compressor, the water injection pump, the liquid flowmeter and the camera through the control cabinet.

3. A method of de-plugging by simulating gas well hydrate plugging using the apparatus of claim 1 or 2, comprising the steps of, in order:

(1) setting the temperature in the constant temperature box as the temperature required by the experiment, filling clear water in the water tank, putting a hydrate on the perforated supporting plate, putting a solid blocking remover on the hydrate, and setting the outlet pressure of the pressure regulating valve;

(2) the gas booster pump injects methane gas into the simulated shaft through the gas injection pipeline, and gas injection is stopped when the pressure in the simulated shaft reaches the pressure required by the experiment;

(3) the water injection pump injects the clear water in the water tank into the simulation shaft through the water injection pipeline, after the clear water is contacted with the solid blocking remover, the hydrate is gradually decomposed by the heat released by the solid blocking remover, the hydrate decomposition process is recorded by the camera, and the temperature and pressure change curve in the blocking removal process is formed by the computer according to the collected temperature, pressure and decomposition process images, and meanwhile, the hydrate decomposition amount, the decomposition rate and the solid blocking remover dosage are obtained.

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