Dosing device

Abstract

The utility model relates to a method for adding chemicals to prevent or limit the corrosion effect of stratum corrosion media on an oil casing in a borehole, in particular to a chemical adding device, which comprises a chemical adding tank, a casing gas outlet pipeline and a chemical adding pipeline, and is characterized in that the chemical adding tank is internally provided with a chemical cavity; the sleeve gas outlet pipeline is provided with a medicament cavity heat exchange section, a heat exchanger structure is formed between the medicament cavity heat exchange section and the medicament cavity, and the heat exchanger structure is used for heat exchange between medicaments in the medicament cavity and sleeve gas in the sleeve gas outlet pipeline. According to the utility model, hot gas rising from the gas outlet pipeline of the sleeve is used for providing a heat source for the dosing tank, so that the problem that dosing cannot be carried out normally in winter due to too low environment temperature in the prior art is solved.

Description

Technical Field

[0001] The utility model relates to a method of adding chemicals to prevent or limit the corrosion of formation corrosive media on oil casing in a wellbore, in particular to a chemical adding device. Background Art

[0002] The dosing device is an important equipment in oil production. It is mainly used to inject specific chemical agents into oil wells and related systems during oil production. These agents can help improve the production effect of oil wells and increase the output and production efficiency of oil fields.

[0003] There are two common dosing methods for dosing devices, namely periodic one-time dosing and continuous dosing. Although periodic one-time dosing is simple, the dosing is uneven and there is a problem of large waste of drugs. Continuous dosing is divided into two types: with external power and without power. The dosing device with external power has problems such as high cost, easy damage of electric dosing pump during continuous operation, high operating cost, and short service life. Therefore, dosing devices mostly use unpowered dosing, but unpowered dosing also has problems such as no drug injection when well is pressed with casing, easy to be affected by liquid height, large flow rate difference of the device, and inability to maintain constant flow.

[0004] In order to solve the above problems, a Chinese invention application with application publication number CN117005828A and application publication date November 7, 2023 discloses a self-gravity intelligent controlled oil well casing automatic dosing device and method, the dosing device includes a control system, a medicine storage tank and a metering tank, the medicine storage tank is arranged above the metering tank, the medicine storage tank is connected to the inlet of the metering tank through a pipeline and a first solenoid valve, the outlet of the metering tank is connected to a connecting pipeline through a pipeline and a second solenoid valve, the connecting pipeline is connected to the oil well casing, the outlet of the metering tank is arranged higher than the oil well casing, the top of the medicine storage tank is connected to the connecting pipeline through the medicine storage tank air pressure balance pipeline, and an air pressure balance gate is provided on the medicine storage tank air pressure balance pipeline; the dosing device also includes a dosage control device for controlling the timed opening and closing of the first solenoid valve and the second solenoid valve.

[0005] The prior art uses an air pressure balance pipeline to balance the air pressure at both ends of the medicine storage tank and the connecting pipeline, solving the problem that the unpowered medicine adding device with a casing does not add medicine when the well is pressed; the electromagnetic valve is intermittently opened and closed to indirectly control the flow rate of the medicine liquid, solving the problem that the unpowered medicine adding device cannot maintain a constant flow. Although the prior art solves the problem that the unpowered medicine adding device with a casing does not add medicine and cannot maintain a constant flow, there is still the problem that the temperature in the medicine storage tank is low in winter, the medicine freezes, and the medicine adding is difficult. Utility Model Content

[0006] The utility model aims to provide a dosing device to solve the problem of low temperature of medicine storage tanks in winter, freezing of medicines and difficulty in dosing in the prior art.

[0007] In order to achieve the above-mentioned purpose, the self-flowing intermittent dosing device of the utility model adopts the following technical solutions:

[0008] A dosing device comprises a dosing tank, a sleeve air outlet pipeline and a dosing pipeline, wherein the dosing tank is provided with a medicine cavity, the sleeve air outlet pipeline has a medicine cavity heat exchange section forming a heat exchanger structure with the medicine cavity, and the heat exchanger structure is used for heat exchange between the medicine in the medicine cavity and the sleeve gas in the sleeve air outlet pipeline.

[0009] Beneficial effects: The utility model is an improved invention. Although the prior art solves the problem that the unpowered dosing device cannot maintain a constant flow and the casing well does not feed medicine through the intermittently opened and closed electromagnetic valve and the air pressure balance pipeline connected to the medicine storage tank and the connecting pipeline, the prior art has the problem of difficulty in dosing medicine in winter due to the low temperature of the medicine storage tank and the freezing of the medicine. The casing air outlet pipeline of the utility model has a heat exchange section that forms a heat exchanger structure with the medicine cavity of the dosing tank, and the heat exchange section can provide a heat source for the medicine cavity, so that the medicine liquid in the dosing tank of the utility model will not be unable to add medicine in winter due to the low temperature and the freezing of the medicine.

[0010] Furthermore, the medicine chamber heat exchange section is located in the medicine chamber, and the chamber wall of the medicine chamber and the air outlet pipeline are sealed and matched.

[0011] Furthermore, the cannula air outlet pipeline passes through the bottom of the medicine cavity and passes through the top of the medicine cavity.

[0012] Furthermore, the diameter of the heat exchange section of the reagent chamber is larger than the diameter of other parts of the sleeve gas outlet pipeline.

[0013] Furthermore, the medicine chamber heat exchange section is located at the center of the medicine chamber.

[0014] Furthermore, a valve chamber is further provided in the dosing tank, the dosing valve on the dosing pipeline is provided in the valve chamber, and the casing air outlet pipeline has a valve chamber heat exchange section which forms a heat exchange structure with the valve chamber.

[0015] Furthermore, the valve chamber is located at the bottom of the dosing tank, and the valve chamber heat exchange section has a horizontal section penetrating into the valve chamber from a side wall of the dosing tank and a vertical section extending vertically into the medicine chamber.

[0016] Furthermore, a dosing valve is arranged on the dosing pipeline, and the dosing valve is a solenoid valve and is connected to a controller for controlling the intermittent opening and closing of the dosing valve.

[0017] Furthermore, the medicine chamber is provided with a liquid level meter, and the liquid level meter is connected to the controller signal, and the controller has a transmitting module for transmitting the low liquid level signal from the liquid level meter to the control room.

[0018] Furthermore, the medicine chamber is provided with a liquid level meter, and the liquid level meter is connected to a low liquid level alarm. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the utility model.

[0020] Figure 1 In: 1. Dosing tank; 2. Chemical chamber; 3. Heat exchange section; 4. Valve chamber; 5. Dosing port; 6. Dosing pipeline; 7. Solenoid valve; 8. Drain valve; 9. Liquid level gauge; 10. Pressure balance hole; 11. Casing air outlet pipeline; 12. Controller; 13. Signal transmitter; 14. Working indicator light; 15. Low liquid level alarm indicator light; 16. Casing air outlet; 17. Oil wellhead; 18. Casing annulus inlet; 19. Baffle. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model, that is, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0022] A specific implementation of a dosing device of the utility model is as follows:

[0023] Metal equipment in oil wells is susceptible to corrosion, which can lead to equipment damage and production interruption. Adding chemical agents such as corrosion inhibitors to oil wells can effectively slow down or prevent corrosion and extend the useful life of equipment.

[0024] There are two ways to add slow-release agents, namely regular one-time dosing and continuous dosing. Since regular one-time dosing has problems such as uneven dosing and a large amount of agent waste, most dosing devices are continuous dosing, and continuous dosing is divided into two types: with external power and without power. Both externally powered and unpowered dosing devices can achieve continuous dosing, but externally powered dosing devices have problems such as high cost, short service life, and easy damage to the electric dosing pump. Unpowered dosing devices also have the problem of being unable to solve the problem of no drug injection and constant flow when wells are being killed with casings.

[0025] In order to solve the above problems, the prior art discloses a self-gravity intelligent controlled oil well casing automatic dosing device and method. Although the device solves the problems of unpowered dosing and inability to maintain a constant flow during well pressure with casing, there are still problems such as no insulation measures for the drug storage tank and the metering tank. In winter, the temperature in the tank is too low, causing the agent to freeze and making it impossible to add drugs.

[0026] In order to solve the problem of difficulty in adding medicine in the prior art due to low temperature in winter, the utility model designs a dosing device. Since the depth of the oil and gas well is deep, the gas discharged from the casing often has a higher temperature. The core idea of ​​this solution is to use the heat of the gas discharged from the casing to form a medicine cavity heat exchange section of a heat exchanger structure between the casing gas outlet pipeline and the medicine cavity, and use the hot gas in the casing gas outlet pipeline to provide a heat source for the dosing tank.

[0027] Based on the above invention concept, Figure 1 In a specific embodiment shown, the dosing device includes a dosing tank 1 and a sleeve gas outlet pipeline 11.

[0028] Specifically, in order to allow the liquid medicine to circulate by its own weight, the dosing tank 11 needs to be placed higher than the oil casing annulus inlet 18, the casing outlet pipeline 11 is connected to the oil casing annulus inlet 18, and the casing outlet pipeline 11 is provided with a pressure balancing hole 10 for balancing the casing outlet pipeline 11 and the dosing tank 1. The dosing tank 1 is a cylindrical barrel with a medicine chamber 2 inside, a dosing port 5 and an exhaust port on the top. In this embodiment, the dosing port 5 and the exhaust port share an opening, and in other embodiments, the dosing port 5 and the exhaust port can also be separately arranged. A baffle is arranged directly below the dosing port 5, and the baffle is welded on the heat exchange section 3. The baffle 19 plays a role of slowing down the flow during the dosing process of this embodiment, so in other embodiments, any structure that can slow down the reflux of the tank body can be adopted.

[0029] A valve chamber 4 is provided at the bottom of the dosing tank 1, and a dosing pipeline 6 and an exhaust valve 8 are installed in the valve chamber 4. The dosing tank 1 is connected to the casing gas outlet pipeline 11 through the dosing pipeline 6, and the dosing pipeline 6 is connected to the solenoid valve 7, and the solenoid valve 7 is connected to the controller 12. The controller 12 can control the intermittent opening and closing of the solenoid valve 7 according to a pre-set program.

[0030] like Figure 1 As shown, in order to prevent the medicine in the medicine cavity from freezing in winter, a heat exchange section 3 of a heat exchanger structure is formed between the sleeve gas outlet pipeline 11 and the medicine cavity 2. It should be particularly noted here that although the pressure balance hole is provided on the heat exchange section, due to its small diameter, even if part of the gas enters the medicine cavity, it does not prevent the heat exchange section and the medicine cavity from still being a heat exchange structure rather than a mixed heating structure.

[0031] The heat exchange section 3 penetrates from the bottom of the medicine chamber 2, passes through the center of the medicine chamber 2, and then passes out from the top of the medicine chamber 2. In this embodiment, the heat exchange section 3 passes through the center of the medicine chamber 2 to allow all solutions in the medicine chamber 2 to transfer heat to prevent them from freezing in winter. However, in other embodiments, the sleeve gas outlet pipeline 11 does not have to be restricted to this order and may not pass through the center of the medicine chamber 2. At the same time, in order to prevent the dosing pipeline 6 in the valve chamber 4 from being frozen in winter, the valve chamber 4 also needs to form a heat exchange section of the valve chamber 4 with the sleeve gas outlet pipeline 11. The heat exchange sections of the valve chamber 4 of the sleeve gas outlet pipeline 11 are respectively the horizontal end that penetrates the valve chamber 4 from the side wall of the dosing tank 1 and the vertical section that extends vertically into the medicine chamber 2. In this embodiment, in order to make the heat exchange more sufficient and the liquid medicine can radiate more heat, the diameter of the sleeve outlet pipe 11 of the heat exchange section 3 is larger than the diameter of the sleeve outlet pipe 11 of other parts, but it is not necessary in other embodiments. The diameter of the sleeve outlet pipe 11 of the heat exchange section 3 can be flexibly changed according to the shape of the dosing tank 1. In this embodiment, the sleeve outlet pipe 11 is formed in the dosing tank 1 by passing through the bottom of the dosing tank and passing through the top. In other embodiments, the sleeve outlet pipe 11 can also be coiled on the outer wall of the dosing tank 1 to form a coiled warm pipe to provide heat for the medicine in the medicine cavity 2.

[0032] like Figure 1 As shown, the medicine chamber 2 is provided with a liquid level meter 9 which can reflect the liquid level at all times.

[0033] Specifically, the signal of the liquid level meter 9 is connected to the signal transmitter 13 of the low liquid level alarm and the controller 12. When the liquid level in the medicine chamber 2 is too low, the low liquid level alarm is triggered. At the same time, the low liquid level signal from the liquid level meter 9 is transmitted to the transmitting module of the control room through the signal transmitter 13.

[0034] The following describes the dosing process in combination with the above embodiments:

[0035] Before the dosing device is operated, the duration of intermittent opening and closing of the solenoid valve 7 is set according to the added medicine, and the casing gas outlet 16 and the dosing port 5 are both in an open state. During operation, the power is turned on to start the controller 12 to control the intermittent operation of the solenoid valve 7, and the liquid medicine is added to the dosing tank 1 from the dosing port 5. When the solenoid valve 7 is fully opened, the working indicator light 14 is on, and the liquid medicine added in the pressurized tank enters the casing gas outlet pipeline 11 along the dosing pipeline 6 and reaches the oil casing annulus inlet 18 at the wellhead 17 of the oil well. When the solenoid valve 7 is fully closed, the working indicator light 14 is off.

[0036] When the liquid medicine is nearly drained, the liquid level alarm is triggered, and the signal is transmitted to the controller 12, and the liquid level alarm indicator light 15 is lit. At the same time, the signal transmitter 13 also transmits the low liquid level signal to the control room.

[0037] In another embodiment of the present invention, when the casing pressure does not exceed the pressure that the dosing tank 1 can withstand, the casing gas outlet 16 can be sealed with a wire plug, and the dosing device uses the pressure balance hole 10 to balance the pressure of the casing gas outlet pipeline 11 and the dosing tank 1, so that the dosing device can still dosing normally.

Claims

1. A dosing device, comprising a dosing tank, a sleeve air outlet pipeline and a dosing pipeline, wherein a medicine chamber is provided in the dosing tank, characterized in that: The sleeve gas outlet pipeline has a medicine cavity heat exchange section which forms a heat exchanger structure with the medicine cavity. The heat exchanger structure is used for heat exchange between the medicine in the medicine cavity and the sleeve gas in the sleeve gas outlet pipeline.

2. The dosing device according to claim 1, characterized in that: The medicine cavity heat exchange section is located in the medicine cavity, and the cavity wall of the medicine cavity is sealed with the air outlet pipeline.

3. The dosing device according to claim 1 or 2, characterized in that: The sleeve air outlet pipeline passes through the bottom of the medicine cavity and passes through the top of the medicine cavity.

4. The dosing device according to claim 3, characterized in that: The diameter of the heat exchange section of the reagent cavity is larger than the diameter of other parts of the sleeve gas outlet pipeline.

5. The dosing device according to claim 3, characterized in that: The medicine chamber heat exchange section is located at the center of the medicine chamber.

6. The dosing device according to claim 1 or 2, characterized in that: The dosing tank is also provided with a valve chamber, the dosing valve on the dosing pipeline is arranged in the valve chamber, and the sleeve air outlet pipeline has a valve chamber heat exchange section which forms a heat exchange structure with the valve chamber.

7. The dosing device according to claim 6, characterized in that: The valve chamber is located at the bottom of the dosing tank, and the valve chamber heat exchange section comprises a horizontal section penetrating into the valve chamber from a side wall of the dosing tank and a vertical section extending vertically into the medicine chamber.

8. The dosing device according to claim 1 or 2, characterized in that: The dosing pipeline is provided with a dosing valve, which is a solenoid valve and is connected to a controller for controlling the intermittent opening and closing of the dosing valve.

9. The dosing device according to claim 8, characterized in that: The medicine chamber is provided with a liquid level meter, and the liquid level meter is connected to the controller signal. The controller has a transmitting module for transmitting the low liquid level signal from the liquid level meter to the control room.

10. The dosing device according to claim 8, characterized in that: The medicine chamber is provided with a liquid level meter, and the liquid level meter is connected to a low liquid level alarm.

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