Tight oil supercritical carbon dioxide extraction testing device under in-situ temperature and pressure conditions

Abstract

The utility model relates to the technical field of supercritical carbon dioxide extraction, in particular to a supercritical carbon dioxide extraction testing device for tight oil under in-situ temperature and pressure conditions. The utility model discloses a supercritical carbon dioxide extraction testing device for tight oil under in-situ temperature and pressure conditions. The supercritical carbon dioxide extraction testing device comprises an intermediate container, a reaction device and a separation device which are connected in sequence, the inlet end of the intermediate container is connected with a pressurized gas input device; a saturated oil core is arranged in the reaction device, and the reaction device is also connected with a pressure regulating device and a temperature control device. The utility model discloses a supercritical carbon dioxide extraction testing device for tight oil under in-situ temperature and pressure conditions. The supercritical carbon dioxide extraction testing device comprises an intermediate container, a reaction device and a separation device which are connected in sequence, the inlet end of the intermediate container is connected with a pressurized gas input device, and a saturated oil core is arranged in the intermediate container; and the reaction device is provided with a pressure regulating device and a temperature control device.

Description

Technical Field

[0001] The utility model relates to the technical field of supercritical carbon dioxide extraction, in particular to a supercritical carbon dioxide extraction test device for dense oil under in-situ temperature and pressure conditions. Background Art

[0002] Supercritical carbon dioxide extraction (SCCO) is an ideal extraction method due to its high extraction capacity, high extraction rate, strong selectivity, absence of harmful residues, and high product quality. However, high equipment manufacturing and operating costs, as well as low efficiency, have limited its industrial application in the extraction of active ingredients from natural products.

[0003] Under existing technical conditions, the supercritical carbon dioxide extraction kettle works intermittently, the production process is very complicated, and the operation is difficult for operators, requiring the operators to have relatively high quality. At the same time, due to the small volume and small processing capacity of the extraction kettle, the production cost is high. At the same time, in the second half of the intermittent extraction, the material obtained by material extraction is greatly reduced, the solubility of carbon dioxide is extremely low, and it is in an extremely unsaturated state for a long time. The carbon dioxide utilization rate is too low, resulting in extremely low equipment utilization, which is extremely unreasonable, thereby increasing the production cost. Summary of the Invention

[0004] In response to the above-mentioned defects or improvement needs of the prior art, the utility model provides a supercritical carbon dioxide extraction test device for tight oil under in-situ temperature and pressure conditions.

[0005] The technical solution of the utility model is:

[0006] A supercritical carbon dioxide extraction test device for tight oil under in-situ temperature and pressure conditions comprises an intermediate container, a reaction device, and a separation device connected in sequence; the inlet end of the intermediate container is connected to a pressurized gas input device; the reaction device has an oil-saturated core built in, and is also connected to a pressure regulating device and a temperature control device.

[0007] The system further comprises a circulation pipeline, wherein the inlet end of the circulation pipeline is connected to the outlet end of the separation device, and the outlet end of the circulation pipeline is connected to the pressurized gas input device.

[0008] The reaction device is a reactor; the reactor is provided with an inlet pipe and an outlet pipe; the pressure regulating device includes an inlet pressure regulating device and an outlet pressure regulating device; the inlet pressure regulating device includes a first confining pressure pump and a first back-pressure valve arranged on the inlet pipe, and the outlet pressure regulating device includes a second confining pressure pump and a second back-pressure valve arranged on the outlet pipe; wherein, the first confining pressure pump and the second confining pressure pump are located outside the constant temperature device, and the first back-pressure valve and the second back-pressure valve are located inside the constant temperature device; the second back-pressure valve is also connected to the inlet end of the separation device.

[0009] The pressurized gas input device includes a carbon dioxide cylinder, a carbon dioxide storage tank and a carbon dioxide booster pump connected in sequence, and the carbon dioxide booster pump is connected to an intermediate container; it also includes a condensing device; the carbon dioxide storage tank is located in the condensing device; the outlet end of the circulation pipeline is connected to the carbon dioxide storage tank.

[0010] The carbon dioxide storage tank is provided with a carbon dioxide inlet pipe and a carbon dioxide outlet pipe; a first pressure regulating valve is provided on the carbon dioxide inlet pipe, and a second pressure regulating valve is provided on the carbon dioxide outlet pipe; the first pressure regulating valve and the second pressure regulating valve are both located outside the condensing device; a third pressure regulating valve is provided on the pipe between the carbon dioxide booster pump and the intermediate container.

[0011] The intermediate container is also connected to a submersible pump.

[0012] The circulation pipeline is provided with a circulation pump and a fourth pressure regulating valve.

[0013] The constant temperature device is a constant temperature box. The condensing device is a condensing box. The separating device is a separator, the inlet end of the separator is connected to the second back pressure valve, and the outlet end of the separator is connected to the circulation pipeline.

[0014] The technical effects of the utility model are:

[0015] The utility model has a simple structure and is easy to operate for operators, requiring relatively low quality of operators. At the same time, the carbon dioxide solubility is high and the carbon dioxide utilization rate is high, resulting in extremely high equipment utilization rate and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of the supercritical carbon dioxide extraction test device for tight oil under in-situ temperature and pressure conditions of the utility model.

[0017] Figure numerals: 1. Carbon dioxide cylinder; 2. Condensation tank; 3. Carbon dioxide storage tank; 4. Carbon dioxide booster pump; 5. Intermediate container; 6. Submersible drive pump; 7. First confining pressure pump; 8. First back pressure valve; 9. Constant temperature box; 10. Reactor; 11. Second back pressure valve; 13. Second confining pressure pump; 14. Separation device; 15. First pressure regulating valve; 16. Circulation pump; 17. Circulation pipeline; 18. Second pressure regulating valve; 19. Third pressure regulating valve; 20. Fourth pressure regulating valve. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0019] Example 1

[0020] A supercritical carbon dioxide extraction test device for tight oil under in-situ temperature and pressure conditions comprises an intermediate container 5, a reaction device and a separation device 14 connected in sequence; the inlet end of the intermediate container 5 is connected to a pressurized gas input device; the reaction device has an oil-saturated core built in, and is also connected to a pressure regulating device and a temperature control device.

[0021] The specific implementation process of this embodiment is as follows:

[0022] Weigh the mass of the oil-saturated core M1;

[0023] An oil-saturated core is placed in a reaction apparatus. Supercritical carbon dioxide gas provided by a pressurized gas input device is introduced into the reaction apparatus through an intermediate container 5. The pressure within the reaction apparatus is adjusted to a constant target experimental pressure by a pressure regulating device, and the temperature within the reaction apparatus is adjusted to a constant target experimental temperature by a temperature control device. An extraction oil recovery experiment is then conducted. After the extraction oil recovery experiment, the pressure within the reaction apparatus is reduced to zero, the supercritical carbon dioxide gas is converted to carbon dioxide gas, the extracted core is removed, and the mass M2 of the extracted core is weighed. The crude oil extraction rate under different experimental conditions is then calculated based on the mass M1 of the oil-saturated core and the mass M2 of the extracted core. The small amount of light crude oil components and carbon dioxide gas extracted in the gaseous phase during the extraction oil recovery experiment are separated in a separation apparatus 14. The liquefied light crude oil components remain in the separation apparatus 14, while the carbon dioxide gas is discharged through the separation apparatus 14.

[0024] Example 2

[0025] In accordance with Example 1, the present invention further comprises a circulation conduit 17, the inlet of which is connected to the outlet of the separation device 14, and the outlet of which is connected to the pressurized gas input device. A circulation pump 16 and a fourth pressure regulating valve 20 are provided on the circulation conduit 17. The carbon dioxide gas separated by the separation device 14 is pressurized again by the circulation pump 16, converted into supercritical carbon dioxide gas, and then reinjected into the pressurized gas input device for reuse.

[0026] Example 3

[0027] On the basis of Example 2, it also includes: the reaction device is a reactor 10; the reactor 10 is provided with an inlet pipe and an outlet pipe; the pressure regulating device includes an inlet pressure regulating device and an outlet pressure regulating device; the inlet pressure regulating device includes a first confining pressure pump 7 and a first back pressure valve 8 arranged on the inlet pipe, and the outlet pressure regulating device includes a second confining pressure pump 13 and a second back pressure valve 11 arranged on the outlet pipe; wherein, the first confining pressure pump 7 and the second confining pressure pump 13 are located outside the constant temperature device, and the first back pressure valve 8 and the second back pressure valve 11 are located inside the constant temperature device; the second back pressure valve 11 is also connected to the inlet end of the separation device 14.

[0028] Example 4

[0029] In accordance with Example 3, the present invention further comprises: the pressurized gas input device comprises a sequentially connected carbon dioxide cylinder 1, a carbon dioxide storage tank 3, and a carbon dioxide booster pump 4, with the carbon dioxide booster pump 4 being connected to an intermediate container 5; a condensing device is also included; the carbon dioxide storage tank 3 is located within the condensing device; the outlet end of the circulation pipeline 17 is connected to the carbon dioxide storage tank 3; the carbon dioxide storage tank 3 is provided with a carbon dioxide inlet pipeline and a carbon dioxide outlet pipeline; the carbon dioxide inlet pipeline is provided with a first pressure regulating valve 15, and the carbon dioxide outlet pipeline is provided with a second pressure regulating valve 18; both the first pressure regulating valve 15 and the second pressure regulating valve 18 are located outside the condensing device; a third pressure regulating valve 19 is provided on the pipeline between the carbon dioxide booster pump 4 and the intermediate container 5; and the intermediate container 5 is further connected to a submersible pump 6.

[0030] Example 5

[0031] Based on Example 4, the invention further comprises: the thermostat is a thermostat box 9, the condensing device is a condensing box 2, and the separating device 14 is a separator, the inlet of the separator is connected to the second back pressure valve 11, and the outlet of the separator is connected to the circulation pipeline 17.

[0032] The specific implementation process of this embodiment is as follows:

[0033] First, weigh the oil-saturated core mass M1;

[0034] Then, the oil-saturated core is placed in a cone-bottom core cup and placed in a reactor 10. The carbon dioxide gas provided by the carbon dioxide cylinder 1 is pressurized by the carbon dioxide storage tank 3 and the carbon dioxide booster pump 4 to form supercritical carbon dioxide gas and enter the intermediate container 5. The submersible pump 6 then provides power to the intermediate container 5 to pass the supercritical carbon dioxide gas into the reactor 10; the temperature of the thermostat 9 is set to a constant target experimental temperature, and the pressure in the reactor 10 is set to a constant target experimental pressure through the inlet pressure regulating device and the outlet pressure regulating device; then, by closing the first back-pressure valve 8 and the second back-pressure valve 11, an extraction oil production experiment is performed on the oil-saturated core in the reactor 10 until the extraction oil production experiment is completed;

[0035] After the extraction oil recovery experiment is completed, the second back-pressure valve 11 is opened to reduce the internal pressure of the reactor 10, gradually destroying the supercritical state of the supercritical carbon dioxide gas and forming carbon dioxide gas. The small amount of light crude oil components and carbon dioxide gas extracted in the gaseous phase during the extraction oil recovery experiment enter the separator for separation. The liquefied light crude oil components remain in the separator. The carbon dioxide gas is pressurized to 20 MPa through the circulation pipeline 17 to form supercritical carbon dioxide gas and re-injected into the carbon dioxide storage tank 3 for reuse. When the internal pressure of the reactor 10 drops to zero, the reactor 10 is opened, the cone-bottom core cup is removed, and then the extracted core is removed and the extracted core mass M2 is weighed. The crude oil extraction rate under different experimental conditions is then calculated based on the oil-saturated core mass M1 and the extracted core mass M2.

[0036] Specific experimental cases

[0037] First, weigh the oil-saturated core mass M1;

[0038] Then, the oil-saturated core is placed in a cone-bottom core cup and placed in a reactor 10. The carbon dioxide gas provided by the carbon dioxide cylinder 1 is pressurized to 20 MPa by the carbon dioxide storage tank 3 and the carbon dioxide booster pump 4 in sequence to form supercritical carbon dioxide gas and then enter the intermediate container 5. The submersible pump 6 then provides power to the intermediate container 5 to pass the supercritical carbon dioxide gas into the reactor 10; the temperature of the thermostat 9 is adjusted to a constant target experimental temperature of 45°C; the pressure in the reactor 10 is set to a constant target experimental pressure of 20 MPa through the inlet pressure regulating device and the outlet pressure regulating device, so that the immersion pressure in the reactor 10 is always stable at 20 MPa; then, by closing the first back pressure valve 8 and the second back pressure valve 11, an extraction oil production experiment is performed on the oil-saturated core in the reactor 10 until the extraction oil production experiment is completed;

[0039] After the extraction oil recovery experiment is completed, the second back-pressure valve 11 is opened to reduce the internal pressure of the reactor 10, gradually destroying the supercritical state of the supercritical carbon dioxide gas and forming carbon dioxide gas. The small amount of light crude oil components and carbon dioxide gas extracted in the gaseous phase during the extraction oil recovery experiment enter the separator for separation. The liquefied light crude oil components remain in the separator. The carbon dioxide gas is pressurized to 20 MPa through the circulation pipeline 17 to form supercritical carbon dioxide gas and re-injected into the carbon dioxide storage tank 3 for reuse. When the internal pressure of the reactor 10 drops to zero, the reactor 10 is opened, the cone-bottom core cup is removed, and then the extracted core is removed and the extracted core mass M2 is weighed. The crude oil extraction rate under different experimental conditions is then calculated based on the oil-saturated core mass M1 and the extracted core mass M2.

[0040] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A supercritical carbon dioxide extraction test device for tight oil under in situ temperature and pressure conditions, characterized by: The invention comprises an intermediate container (5), a reaction device and a separation device (14) connected in sequence; the inlet end of the intermediate container (5) is connected to a pressurized gas input device; the reaction device has an oil-saturated core built in, and is also connected to a pressure regulating device and a temperature control device.

2. The supercritical carbon dioxide extraction test device for tight oil under in situ temperature and pressure conditions according to claim 1, characterized in that: The invention also comprises a circulation pipeline (17), wherein the inlet end of the circulation pipeline (17) is connected to the outlet end of the separation device (14), and the outlet end of the circulation pipeline (17) is connected to the pressurized gas input device.

3. The supercritical carbon dioxide extraction test device for tight oil under in situ temperature and pressure conditions according to claim 2, characterized in that: The reaction device is a reactor (10); the reactor (10) is provided with an inlet pipe and an outlet pipe; the pressure regulating device includes an inlet pressure regulating device and an outlet pressure regulating device; the inlet pressure regulating device includes a first confining pressure pump (7) and a first back pressure valve (8) arranged on the inlet pipe, and the outlet pressure regulating device includes a second confining pressure pump (13) and a second back pressure valve (11) arranged on the outlet pipe; wherein, the first confining pressure pump (7) and the second confining pressure pump (13) are located outside the constant temperature device, and the first back pressure valve (8) and the second back pressure valve (11) are located inside the constant temperature device; the second back pressure valve (11) is also connected to the inlet end of the separation device (14).

4. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 3, characterized in that: The pressurized gas input device comprises a carbon dioxide gas cylinder (1), a carbon dioxide storage tank (3) and a carbon dioxide booster pump (4) connected in sequence, wherein the carbon dioxide booster pump (4) is connected to an intermediate container (5); and further comprises a condensing device; the carbon dioxide storage tank (3) is located in the condensing device; and the outlet end of the circulation pipe (17) is connected to the carbon dioxide storage tank (3).

5. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 4, characterized in that: The carbon dioxide storage tank (3) is provided with a carbon dioxide inlet pipeline and a carbon dioxide outlet pipeline; a first pressure regulating valve (15) is provided on the carbon dioxide inlet pipeline, and a second pressure regulating valve (18) is provided on the carbon dioxide outlet pipeline; the first pressure regulating valve (15) and the second pressure regulating valve (18) are both located outside the condensing device; and a third pressure regulating valve (19) is provided on the pipeline between the carbon dioxide booster pump (4) and the intermediate container (5).

6. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 1, characterized in that: The intermediate container (5) is also connected to a submersible pump (6).

7. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 2, characterized in that: The circulation pipeline (17) is provided with a circulation pump (16) and a fourth pressure regulating valve (20).

8. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 1, characterized in that: The constant temperature device is a constant temperature box (9).

9. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 1, characterized in that: The condensing device is a condensing box (2).

10. The supercritical carbon dioxide extraction testing device for tight oil under in situ temperature and pressure conditions according to claim 3, characterized in that: The separation device (14) is a separator, the inlet end of the separator is connected to the second back pressure valve (11), and the outlet end of the separator is connected to the circulation pipeline (17).

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