Carbon dioxide displacement experiment system

Abstract

The utility model discloses a carbon dioxide displacement experiment system. The carbon dioxide displacement experiment system comprises a core holder, a first container, a second container, a third container, a pumping device, a resistance measuring instrument and a constant temperature device, an outlet of the first container is connected with a fluid inlet of the core holder through a first pipeline, and a first valve is arranged on the first pipeline. An outlet of the second container is connected with a fluid inlet of the core holder through a second pipeline; and a second valve is arranged on the second pipeline. An outlet of the third container is connected with a fluid inlet of the core holder through a third pipeline; and a third valve is arranged on the third pipeline. An outlet of the pumping device is communicated with an inlet of the first container so as to pump crude oil into the core holder, an outlet of the pumping device is communicated with an inlet of the second container so as to pump formation water into the core holder, and an outlet of the pumping device is communicated with an inlet of the third container so as to pump carbon dioxide into the core holder. And the input end of the resistance measuring instrument is electrically connected with the electric signal interface of the core holder.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas reservoir engineering, and in particular to a carbon dioxide displacement experimental system. Background Art

[0002] In oil and gas reservoir engineering, carbon dioxide displacement technology is an effective method to increase production. By injecting carbon dioxide into the formation, the low viscosity and good diffusivity of carbon dioxide are utilized to increase oil and gas production.

[0003] Core flooding experiments are an important means of simulating actual formation conditions and studying the effect of carbon dioxide displacement. Resistivity is an important parameter of formation rock physical properties, and its change can reflect the change of formation fluid properties during the displacement process. Therefore, the measurement of resistivity in core flooding experiments is of great significance for analyzing the displacement effect. However, it is difficult to accurately measure resistivity in existing core flooding experimental devices, and the analysis of displacement effect is not ideal. Utility Model Content

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a carbon dioxide displacement experimental system, which can solve the problem that the traditional core displacement experimental device is difficult to accurately measure the resistivity.

[0005] The carbon dioxide displacement experimental system according to the embodiment of the present application includes:

[0006] Core holder, used to place the core;

[0007] A first container, for containing crude oil, wherein an outlet of the first container is connected to a fluid inlet of the core holder via a first pipeline, and a first valve is provided on the first pipeline;

[0008] A second container, used to contain water, wherein an outlet of the second container is connected to a fluid inlet of the core holder via a second pipeline, and a second valve is provided on the second pipeline;

[0009] A third container, used to contain carbon dioxide, wherein the outlet of the third container is connected to the fluid inlet of the core holder through a third pipeline, and a third valve is provided on the third pipeline;

[0010] a pumping device, wherein the outlet of the pumping device is connected to the inlet of the first container for pumping the crude oil into the core holder, the outlet of the pumping device is connected to the inlet of the second container for pumping the water into the core holder, and the outlet of the pumping device is connected to the inlet of the third container for pumping the carbon dioxide into the core holder;

[0011] A resistance measuring instrument, wherein the input end of the resistance measuring instrument is electrically connected to the electrical signal interface of the core holder for measuring the resistance of the core, and the output end of the resistance measuring instrument is electrically connected to a host computer;

[0012] The constant temperature device is used to keep the core holder, the first container, the second container, the third container and the resistance measuring instrument at a preset experimental temperature.

[0013] The carbon dioxide displacement experimental system according to the embodiment of the present application has at least the following beneficial effects:

[0014] The first valve, the second valve and the third valve are opened respectively, and the pumping device pumps crude oil, water and carbon dioxide into the core holder respectively, and the resistance of the core is measured by the resistance measuring instrument to obtain the resistivity of the core. The core holder, the first container, the second container, the third container and the resistance measuring instrument are all at a preset experimental temperature through the constant temperature device, which can avoid the influence of the temperature difference of each device on the measured core resistance. Compared with the traditional core displacement experimental device, the carbon dioxide displacement experimental system of the embodiment of the present application can accurately measure the resistance of the core, so as to better analyze the displacement effect.

[0015] According to some embodiments of the present application, a recovery module is also included, which includes a gas-liquid separation device, a gas collecting device and a liquid collecting device. The fluid outlet of the core clamp is connected to the inlet of the gas-liquid separation device through a fourth pipeline, the gas outlet of the gas-liquid separation device is connected to the inlet of the gas collecting device, and the liquid outlet of the gas-liquid separation device is connected to the inlet of the liquid collecting device.

[0016] According to some embodiments of the present application, the liquid collecting device includes an oil-water separator, a first liquid collector and a second liquid collector, the liquid outlet of the gas-liquid separation device is connected to the inlet of the oil-water separator, the oil body outlet of the oil-water separator is connected to the first liquid collector, and the water body outlet of the oil-water separator is connected to the second liquid collector.

[0017] According to some embodiments of the present application, a back pressure device is provided on the fourth pipeline.

[0018] According to some embodiments of the present application, the back-pressure device includes a back-pressure valve and a back-pressure pump, the back-pressure valve is arranged on the fourth pipeline, and the back-pressure pump is connected to the back-pressure valve.

[0019] According to some embodiments of the present application, a confining pressure pump is further included, and the confining pressure pump is connected to the confining pressure interface of the core clamp.

[0020] According to some embodiments of the present application, a first flow meter is provided on the first pipeline.

[0021] According to some embodiments of the present application, a second flow meter is provided on the second pipeline.

[0022] According to some embodiments of the present application, a third flow meter is provided on the third pipeline.

[0023] According to some embodiments of the present application, a multi-way valve is further included, wherein the outlet of the first pipeline is connected to the first inlet of the multi-way valve, the outlet of the second pipeline is connected to the second inlet of the multi-way valve, the outlet of the third pipeline is connected to the third inlet of the multi-way valve, and the outlet of the multi-way valve is connected to the fluid inlet of the core clamp.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present application is further described below with reference to the accompanying drawings and embodiments, wherein:

[0026] Figure 1 This is a schematic diagram of the structure of a carbon dioxide displacement experimental system in one embodiment of the present application;

[0027] Figure 2 It is a cross-sectional view of a core holder in one embodiment of the present application.

[0028] Reference numerals:

[0029] Core holder 100, core 110, confining pressure chamber 120, confining pressure interface 130, holder tube 140, piston limit column 150, first flow channel 160, second flow channel 170, first electrical signal interface 180, second electrical signal interface 190,

[0030] The first container 200, the second container 210, the third container 220,

[0031] The first pipeline 300, the second pipeline 310, the third pipeline 320, the fourth pipeline 330, the fifth pipeline 340, the sixth pipeline 350,

[0032] a first valve 400 , a second valve 410 , a third valve 420 , a fourth valve 430 , a fifth valve 440 , a back pressure valve 450 , a first six-way valve 460 , a second six-way valve 470 ,

[0033] Pumping device 500, back pressure pump 510, confining pressure pump 520,

[0034] Resistance meter 600,

[0035] Constant temperature device 700,

[0036] Gas-liquid separation device 800, gas collection device 810, oil-water separator 820, first liquid collector 830, second liquid collector 840,

[0037] A first flow meter 900 , a second flow meter 910 , a third flow meter 920 , and a fourth flow meter 930 . DETAILED DESCRIPTION

[0038] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0039] In the description of the present application, it should be understood that the descriptions involving orientation, such as the orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In the description of this application, "a plurality" means more than two. If there is a description of "first" or "second", it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0041] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0042] Refer to the following Figure 1 to Figure 2 A carbon dioxide displacement experimental system according to an embodiment of the present application is described.

[0043] According to the carbon dioxide displacement experimental system of the embodiment of the present application, Figure 1As shown, it includes: a core holder 100, a first container 200, a second container 210, a third container 220, a pumping device 500, a resistance measuring instrument 600 and a constant temperature device 700. The core holder 100 is used to place the core 110. The first container 200 is used to contain crude oil, and the outlet of the first container 200 is connected to the fluid inlet of the core holder 100 through a first pipeline 300, and a first valve 400 is provided on the first pipeline 300. The second container 210 is used to contain formation water, and the outlet of the second container 210 is connected to the fluid inlet of the core holder 100 through a second pipeline 310, and a second valve 410 is provided on the second pipeline 310. The third container 220 is used to contain carbon dioxide, and the outlet of the third container 220 is connected to the fluid inlet of the core holder 100 through a third pipeline 320, and a third valve 420 is provided on the third pipeline 320. The outlet of the pumping device 500 is connected to the inlet of the first container 200 through the first six-way valve 460 for pumping crude oil into the core holder 100, the outlet of the pumping device 500 is connected to the inlet of the second container 210 through the first six-way valve 460 for pumping formation water into the core holder 100, and the outlet of the pumping device 500 is connected to the inlet of the third container 220 through the first six-way valve 460 for pumping carbon dioxide into the core holder 100. The first electrical signal input end of the resistance measuring instrument 600 is electrically connected to the first electrical signal interface 180 of the core holder 100, and the second electrical signal input end of the resistance measuring instrument 600 is electrically connected to the second electrical signal interface 190 of the core holder 100 for measuring the resistance of the core 110. The output end of the resistance measuring instrument 600 is used to be electrically connected to the host computer. The constant temperature device 700 is used to keep the core holder 100, the first container 200, the second container 210, the third container 220 and the resistance measuring instrument 600 at a preset experimental temperature.

[0044] In this embodiment, the first valve 400, the second valve 410 and the third valve 420 are opened respectively, the pumping device 500 pumps crude oil, formation water and carbon dioxide into the core holder 100 respectively, and the resistance measuring instrument 600 is used to measure the resistance of the core 110, thereby obtaining the resistivity of the core 110. The core holder 100, the first container 200, the second container 210, the third container 220 and the resistance measuring instrument 600 are all at a preset experimental temperature through the constant temperature device 700, which can avoid the influence of the temperature difference of each device on the measurement of the resistance of the core 110. Compared with the traditional core 110 displacement experimental device, the carbon dioxide displacement experimental system of the embodiment of the present application can measure the resistance of the core 110 in real time and accurately, so as to better analyze the displacement effect.

[0045] It can be understood that the pumping device 500 is a displacement pump. The first container 200, the second container 210 and the third container 220 are all steel cylinders. The constant temperature device 700 is a constant temperature box, and the core holder 100, the first container 200, the second container 210, the third container 220 and the resistance measuring instrument 600 are all placed in the constant temperature box.

[0046] It should be noted that if Figure 2 As shown, a confining pressure chamber 120 and a confining pressure interface 130 connected to the confining pressure chamber 120 are provided in the core holder 100, a holder cylinder 140 is provided in the confining pressure chamber 120, and the core 110 is placed in the holder cylinder 140. Two piston limit columns 150 are provided in the holder cylinder 140, and the two piston limit columns 150 respectively abut the two ends of the core 110, and a first flow channel 160 is provided in one piston limit column 150, and the first flow channel 160 respectively connects the fluid inlet of the holder cylinder 140 and the core holder 100. A second flow channel 170 is provided in the other piston limit column 150, and the second flow channel 170 respectively connects the fluid outlet of the holder cylinder 140 and the core holder 100. Both piston limit columns 150 are electrically connected to the resistance measuring instrument 600, so as to form an electrical circuit to measure the resistance of the core 110.

[0047] In one embodiment of the present application, Figure 1 As shown, it also includes a recovery module, which includes a gas-liquid separation device 800, a gas collecting device 810 and a liquid collecting device. The fluid outlet of the core clamp 100 is connected to the inlet of the gas-liquid separation device 800 through the fourth pipeline 330, the gas outlet of the gas-liquid separation device 800 is connected to the inlet of the gas collecting device 810, and the liquid outlet of the gas-liquid separation device 800 is connected to the inlet of the liquid collecting device.

[0048] In this embodiment, the fluid discharged from the fluid outlet of the core clamp 100 is separated into gas and liquid by the gas-liquid separation device 800, the gas is mainly carbon dioxide, and the liquid is mainly crude oil and formation water. The separated carbon dioxide enters the gas collection device 810, and the separated crude oil and formation water enter the liquid collection device, thereby realizing the recovery of carbon dioxide, crude oil and formation water.

[0049] It should be noted that the gas outlet of the gas-liquid separation device 800 is connected to the gas collection device 810 through the fifth pipeline 340, and the fifth pipeline 340 is provided with a fourth valve 430 and a fourth flow meter 930. The fourth valve 430 can control the degree of conduction of the fifth pipeline 340, and the fourth flow meter 930 can measure the gas flow of the fifth pipeline 340.

[0050] In one embodiment of the present application, Figure 1As shown, the liquid collecting device includes an oil-water separator 820, a first liquid collector 830 and a second liquid collector 840, the liquid outlet of the gas-liquid separation device 800 is connected to the inlet of the oil-water separator 820, the oil body outlet of the oil-water separator 820 is connected to the first liquid collector 830, and the water body outlet of the oil-water separator 820 is connected to the second liquid collector 840.

[0051] In this embodiment, the liquid separated by the gas-liquid separation device 800 is separated into crude oil and formation water by the oil-water separator 820 , the crude oil enters the first liquid collector 830 , and the formation water enters the second liquid collector 840 .

[0052] It can be understood that the liquid outlet of the gas-liquid separation device 800 is connected to the liquid collection device through the sixth pipeline 350, and the sixth pipeline 350 is provided with a fifth valve 440, and the conductance of the sixth pipeline 350 can be controlled by the fifth valve 440.

[0053] In one embodiment of the present application, Figure 1 As shown, a confining pressure pump 520 is also included, and the confining pressure pump 520 is connected to the confining pressure interface 130 of the core holder 100 .

[0054] In this embodiment, confining pressure is applied to the core holder 100 by the confining pressure pump 520 to simulate actual formation conditions.

[0055] In one embodiment of the present application, Figure 1 As shown, a back-pressure device is provided on the fourth pipeline 330 , and the back-pressure device includes a back-pressure valve 450 and a back-pressure pump 510 . The back-pressure valve 450 is provided on the fourth pipeline 330 , and the back-pressure pump 510 is connected to the back-pressure valve 450 .

[0056] In this embodiment, since the fluid pressure discharged from the core holder 100 is relatively high, the pressure in the fourth pipeline 330 is adjusted by a back pressure device.

[0057] In one embodiment of the present application, Figure 1 As shown, a first flow meter 900 is disposed on the first pipeline 300 .

[0058] In this embodiment, the flow rate of the crude oil in the first pipeline 300 is monitored by the first flow meter 900 .

[0059] In one embodiment of the present application, Figure 1 As shown, a second flow meter 910 is disposed on the second pipeline 310 .

[0060] In this embodiment, the flow rate of the formation water in the second pipeline 310 is monitored by the second flow meter 910 .

[0061] In one embodiment of the present application, Figure 1As shown, a third flow meter 920 is disposed on the third pipeline 320 .

[0062] In this embodiment, the flow rate of carbon dioxide in the third pipeline 320 is monitored by the third flow meter 920 .

[0063] According to some embodiments of the present application, Figure 1 As shown, a multi-way valve is also included, and the multi-way valve is a second six-way valve 470. The outlet of the first pipeline 300 is connected to the first inlet of the multi-way valve, the outlet of the second pipeline 310 is connected to the second inlet of the multi-way valve, and the outlet of the third pipeline 320 is connected to the third inlet of the multi-way valve. The outlet of the multi-way valve is connected to the fluid inlet of the core clamp 100.

[0064] In this embodiment, the first pipeline 300, the second pipeline 310 and the third pipeline 320 are respectively connected to the fluid inlet of the core clamp 100 through a multi-way valve, and the first pipeline 300, the second pipeline 310 and the third pipeline 320 can be respectively connected through the multi-way valve.

[0065] In addition, an embodiment of the present application further discloses a carbon dioxide displacement experimental method, comprising:

[0066] Step S100: putting the prepared core 110 into the core holder 100 and assembling it;

[0067] Step S200: placing the core holder 100 in a constant temperature box, and connecting the core holder 100 to the resistance measuring instrument 600, a multi-way valve and other equipment;

[0068] Step S300: Add confining pressure to the core holder 100. When the preset confining pressure value is reached, start the displacement pump and inject formation water at a constant pressure until a large amount of water is produced at the tail end of the core 110. Record the amount of pumped liquid to obtain the core 110 saturated with formation water;

[0069] Step S400: pumping in carbon dioxide, measuring the water production at the tail end of the core holder 100, and obtaining core 110 samples with different water saturations according to the difference in water production;

[0070] Step S500: Inject the prepared crude oil at a constant pressure. Record the amount of liquid pumped in. After the core 110 reaches the designed oil saturation, place it for aging for 1-3 days;

[0071] Step S600: Start the resistance measuring instrument 600 and start injecting carbon dioxide at the same time, and continuously monitor the resistance value at both ends of the core holder 100 every 5 seconds until the outlet end stops producing oil or a large amount of carbon dioxide gushes out;

[0072] Step S700: Calculate the resistivity of the core 110 according to the measured resistance, and analyze the resistivity change of the core 110 before and after the carbon dioxide displacement.

[0073] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present application.

Claims

1. A carbon dioxide displacement experimental system, characterized in that: include: Core holder, used to place the core; A first container, for containing crude oil, wherein an outlet of the first container is connected to a fluid inlet of the core holder via a first pipeline, and a first valve is provided on the first pipeline; A second container, used to contain water, wherein an outlet of the second container is connected to a fluid inlet of the core holder via a second pipeline, and a second valve is provided on the second pipeline; A third container, used to contain carbon dioxide, wherein the outlet of the third container is connected to the fluid inlet of the core holder through a third pipeline, and a third valve is provided on the third pipeline; a pumping device, wherein the outlet of the pumping device is connected to the inlet of the first container for pumping the crude oil into the core holder, the outlet of the pumping device is connected to the inlet of the second container for pumping the water into the core holder, and the outlet of the pumping device is connected to the inlet of the third container for pumping the carbon dioxide into the core holder; A resistance measuring instrument, wherein the input end of the resistance measuring instrument is electrically connected to the electrical signal interface of the core holder for measuring the resistance of the core, and the output end of the resistance measuring instrument is electrically connected to a host computer; The constant temperature device is used to keep the core holder, the first container, the second container, the third container and the resistance measuring instrument at a preset experimental temperature.

2. The carbon dioxide displacement experimental system according to claim 1, characterized in that: It also includes a recovery module, which includes a gas-liquid separation device, a gas collecting device and a liquid collecting device. The fluid outlet of the core clamp is connected to the inlet of the gas-liquid separation device through a fourth pipeline, the gas outlet of the gas-liquid separation device is connected to the inlet of the gas collecting device, and the liquid outlet of the gas-liquid separation device is connected to the inlet of the liquid collecting device.

3. The carbon dioxide displacement experimental system according to claim 2, characterized in that: The liquid collecting device includes an oil-water separator, a first liquid collector and a second liquid collector. The liquid outlet of the gas-liquid separation device is connected to the inlet of the oil-water separator, the oil body outlet of the oil-water separator is connected to the first liquid collector, and the water body outlet of the oil-water separator is connected to the second liquid collector.

4. The carbon dioxide displacement experimental system according to claim 2, characterized in that: The fourth pipeline is provided with a back pressure device.

5. The carbon dioxide displacement experimental system according to claim 4, characterized in that: The back-pressure device comprises a back-pressure valve and a back-pressure pump. The back-pressure valve is arranged on the fourth pipeline, and the back-pressure pump is connected to the back-pressure valve.

6. The carbon dioxide displacement experimental system according to claim 1, characterized in that: It also includes a confining pressure pump, which is connected to the confining pressure interface of the core clamp.

7. The carbon dioxide displacement experimental system according to claim 1, characterized in that: The first pipeline is provided with a first flow meter.

8. The carbon dioxide displacement experimental system according to claim 1, characterized in that: The second pipeline is provided with a second flow meter.

9. The carbon dioxide displacement experimental system according to claim 1, characterized in that: The third pipeline is provided with a third flow meter.

10. The carbon dioxide displacement experimental system according to claim 1, characterized in that: It also includes a multi-way valve, wherein the outlet of the first pipeline is connected to the first inlet of the multi-way valve, the outlet of the second pipeline is connected to the second inlet of the multi-way valve, the outlet of the third pipeline is connected to the third inlet of the multi-way valve, and the outlet of the multi-way valve is connected to the fluid inlet of the core clamp.

Images