Carbon dioxide hydrate carbon sequestration microfluidic experimental device

Abstract

The utility model relates to a carbon dioxide hydrate carbon sequestration micro-fluidic experimental device which comprises a pressure-resistant micro-fluidic hydrate reaction system, a micro-fluid injection and pressure control system, a pressure and temperature real-time display system and a gas introduction system, the pressure-resistant micro-fluidic hydrate reaction system comprises a pressure-resistant micro-fluidic chip, a tablet and a confining pressure kettle, the pressure-resistant micro-fluidic chip is fixed in the confining pressure kettle through the tablet, the pressure-resistant micro-fluidic chip is a glass micro-fluidic chip with four injection holes, the confining pressure kettle is provided with four gas-liquid channels, the four injection holes correspond to the four gas-liquid channels, and the four gas-liquid channels are communicated with the pressure-resistant micro-fluidic chip. The four gas-liquid channels comprise three injection channels and a liquid outlet channel. The gas-liquid two-phase displacement flow in the hydrate can be realized so as to achieve a better gas-liquid mixing ratio, and the simultaneous injection of liquid and gas is realized through multiple channels, so that the device is more suitable for a complex environment in seabed sediments, and the diversity and authenticity of an experiment are improved.

Description

Technical Field

[0001] This utility model relates to the field of gas hydrate experimental technology, and in particular to a microfluidic experimental device for carbon dioxide hydrate carbon sequestration. Background Technology

[0002] Carbon dioxide hydrate is a cage-like crystalline compound formed by CO2 molecules and water under low temperature and high pressure conditions. Its structure is similar to that of natural gas hydrate, and it has become a key research direction in the field of carbon sequestration and capture in recent years. Current research on CO2 hydrate focuses on large-scale carbon sequestration in the deep-sea environment, such as by simulating the formation conditions of natural gas hydrate to sequester CO2 in solid form within seabed sediments. At the application level, CO2 hydrate technology can be coupled with carbon capture and storage (CCS) processes. For example, high-concentration CO2 from industrial emission sources can be directly solidified under low temperature and high pressure and then injected into the seabed for long-term storage. Simultaneously, CO2 can be used to replace methane in natural gas hydrates, forming a "carbon sequestration-energy extraction" co-production model to improve economic efficiency.

[0003] Current technological bottlenecks include maintaining a high-pressure environment in the deep sea, monitoring the stability of long-term storage, and cost control. Microfluidic devices for hydrates can effectively observe their microscopic processes, thus addressing these challenges. A microfluidic device is an experimental platform based on micrometer-level channel networks and precision fluid control technology. It can simulate complex multiphase coupling processes at the microscale, and is particularly suitable for studying the formation and storage mechanisms of carbon dioxide hydrates in seabed sediments.

[0004] However, existing microfluidic devices still face significant technical bottlenecks in simulating seabed sediment environments, primarily due to environmental simulation distortion caused by structural simplification and insufficient multiphase coupling capabilities. Existing microfluidic devices employ a single air-liquid inlet channel design (e.g., single-tube injection of CO2 and pore water), which fails to simulate the multi-channel seepage characteristics of porous media in real sediments, resulting in a singular CO2 transport path. In reality, CO2 within seabed sediment layers may diffuse through complex pathways such as fracture networks, bio-disturbed pores, or clay interlayers. The single-channel design of existing microfluidic devices struggles to reproduce these heterogeneous structures, leading to systematic deviations between experimental data and real-world scenarios for key parameters such as hydrate formation rate and sequestration space distribution.

[0005] Therefore, there is an urgent need for a more efficient and reliable microfluidic experimental device for carbon dioxide hydrate carbon sequestration. Utility Model Content

[0006] To address the problem that existing microfluidic devices cannot simulate the multi-channel seepage characteristics of porous media in real sediments in simulated seabed sediment environments, resulting in a single CO2 transport path and systematic deviations between experimental data and real-world scenarios for key parameters such as hydrate formation rate and sequestration space distribution, this invention provides a microfluidic experimental device for carbon dioxide hydrate carbon sequestration.

[0007] To solve the above-mentioned technical problems, one technical solution adopted by this utility model is to provide a microfluidic experimental device for carbon dioxide hydrate carbon sequestration. The microfluidic experimental device for carbon dioxide hydrate carbon sequestration includes a pressure-resistant microfluidic hydrate reaction system, a microfluidic injection and pressure control system, a pressure and temperature real-time display system, and a gas introduction system. The microfluidic injection and pressure control system, the pressure and temperature real-time display system, and the gas introduction system are all connected to the pressure-resistant microfluidic hydrate reaction system. The microfluidic injection and pressure control system quantitatively injects liquid into the pressure-resistant microfluidic hydrate reaction system and adjusts the pressure-resistant microfluidic hydrate system in real time. The pressure in the hydrate reaction system is monitored in real time by a pressure and temperature real-time display system. A gas introduction system introduces gas into the pressure-resistant microfluidic hydrate reaction system. The pressure-resistant microfluidic hydrate reaction system includes a pressure-resistant microfluidic chip, a pressure plate, and a pressure vessel. The pressure plate fixes the pressure-resistant microfluidic chip in the pressure vessel. The pressure-resistant microfluidic chip is a glass microfluidic chip with four injection holes. The pressure vessel has four gas-liquid channels, with the four injection holes corresponding to the four gas-liquid channels. The four gas-liquid channels include three injection channels and one outlet channel.

[0008] In one embodiment, the microfluidic injection and pressure control system includes a CNC injection pump and two pressure-resistant piston containers filled with liquid. The CNC injection pump controls the pressure-resistant piston containers to inject liquid into the pressure-resistant microfluidic chip through three injection channels.

[0009] In one embodiment, the gas inlet system includes a gas cylinder and a pressure regulating valve. The gas cylinder is filled with gas and is connected to three injection channels. The pressure regulating valve adjusts the rate at which the gas in the gas cylinder is introduced into the pressure-resistant microfluidic chip to control the pressure of the hydrate reaction.

[0010] In one embodiment, the pressure-resistant microfluidic hydrate reaction system further includes a confining pressure control pump and a back pressure valve. Both the confining pressure control pump and the back pressure valve are connected to the confining pressure vessel. The confining pressure control pump is used to provide protective pressure to the cavity of the confining pressure vessel, and the protective pressure is greater than the pressure of the pressure-resistant microfluidic chip. The back pressure valve is used to adjust the pressure difference between the internal and external environments of the pressure-resistant microfluidic chip, so that the external environment pressure of the pressure-resistant microfluidic chip is greater than the internal environment pressure of the pressure-resistant microfluidic chip, and to depressurize the pressure-resistant microfluidic chip when it is no longer in use.

[0011] In one embodiment, the protection pressure is 1 to 2 MPa higher than the pressure of the pressure-resistant microfluidic chip.

[0012] In one embodiment, the back pressure valve controls the internal and external environmental pressure difference of the pressure-resistant microfluidic chip to be 1 MPa.

[0013] In one embodiment, the microfluidic experimental device for carbon dioxide hydrate carbon sequestration further includes a temperature control system, which includes a water bath temperature control device, a temperature control jacket, and a quartz wool outer layer. The temperature control jacket is matched with the pressure vessel, and the quartz wool outer layer is placed at the connection between the temperature control jacket and the pressure vessel. The water bath temperature control device achieves liquid circulation cooling by cooling ethylene glycol antifreeze and injecting it into the temperature control jacket.

[0014] In one embodiment, the pressure vessel includes a fixed base and a pressure cover, the gas-liquid channel is disposed on the fixed base, and the fixed base and the pressure cover are fixed by fourteen first metal screws.

[0015] In one embodiment, the carbon dioxide hydrate carbon sequestration microfluidic experimental device further includes an image acquisition system, and the pressure vessel further includes a sapphire window. The image acquisition system includes a camera, a camera lens, and a ring light source. The ring light source is placed on one side of the pressure vessel, and the camera and the camera lens are placed on the opposite side of the pressure vessel. The camera lens is used to adjust the magnification. The camera observes and acquires images of the hydrate reaction inside the pressure-resistant microfluidic chip in real time through the sapphire window.

[0016] In one embodiment, the pressure plate is an eight-hole metal disc pressure plate, and the pressure plate is used to fix the pressure-resistant microfluidic chip in the pressure vessel by four second metal screws and four rubber screws.

[0017] Compared with the prior art, the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the invention has the following advantages:

[0018] 1. In the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the present invention, a microfluidic injection and pressure control system quantitatively injects liquid into a pressure-resistant microfluidic hydrate reaction system and adjusts the pressure in the pressure-resistant microfluidic hydrate reaction system in real time. A pressure and temperature real-time display system detects the temperature and pressure in the pressure-resistant microfluidic hydrate reaction system in real time. A gas inlet system introduces gas into the pressure-resistant microfluidic hydrate reaction system. The pressure-resistant microfluidic hydrate reaction system includes a pressure-resistant microfluidic chip, a pressure plate, and a pressure vessel. The pressure plate fixes the pressure-resistant microfluidic chip in the pressure vessel. The pressure-resistant microfluidic chip is a glass microfluidic chip with four injection holes. The pressure vessel is provided with four gas-liquid channels, and the four injection holes correspond to the four gas-liquid channels. The four gas-liquid channels include three injection channels and one liquid outlet channel. This invention, by setting four gas-liquid channels in a confined pressure vessel in conjunction with four injection holes in a pressure-resistant microfluidic chip, creates multiphase flow within the channels of the pressure-resistant microfluidic chip. This solves the problem that existing microfluidic devices cannot simulate the multi-channel seepage characteristics of porous media in real sediments in simulated seabed sediment environments, leading to a single CO2 transport path and systematic deviations in experimental data of key parameters such as hydrate formation rate and sequestration space distribution from real-world scenarios. It enables two-phase displacement flow of gas and liquid in hydrates to achieve a better gas-liquid mixing ratio and allows for simultaneous injection of liquid and gas through multiple channels, better reflecting the complex environment of seabed sediments and increasing the diversity and realism of experiments.

[0019] 2. In the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment, the microfluidic injection and pressure control system includes a CNC injection pump and two pressure-resistant piston containers. The pressure-resistant piston containers are filled with liquid, and the CNC injection pump controls the pressure-resistant piston containers to inject liquid into the pressure-resistant microfluidic chip through three injection channels. By setting the CNC injection pump and the two pressure-resistant piston containers in coordination, the problem of existing microfluidic devices being limited by the single liquid storage tube design in the dynamic interaction research of multiphase fluids (such as CO2-seawater-methane coexistence systems), and unable to simulate the multiphase interface oscillation effects caused by tidal activity, seabed seepage, etc., leading to a lack of understanding of the sediment-hydrate-fluid coupling mechanism is solved. This device can realize real-time liquid control and injection, and can also realize multiple liquid displacement, improving the utilization efficiency and experimental diversity of the pressure-resistant microfluidic chip.

[0020] 3. In the microfluidic experimental device for carbon dioxide hydrate carbon encapsulation provided in this embodiment of the present invention, the confining pressure liquid control pump is connected to the confining pressure vessel. By setting the confining pressure liquid control pump, a protective pressure greater than the internal pressure of the pressure-resistant microfluidic chip can be provided to the cavity of the confining pressure vessel, thereby preventing the pressure-resistant microfluidic chip from being damaged due to excessive internal pressure during the use of the pressure-resistant microfluidic hydrate reaction system.

[0021] In addition, the back pressure valve is connected to the confined pressure vessel. By setting the back pressure valve, the external environmental pressure of the pressure-resistant microfluidic chip can be adjusted to be greater than the internal environmental pressure, which is equivalent to closing a door to prevent gas and liquid from escaping from the pressure-resistant microfluidic chip during operation. At the same time, when the use is over, the pressure in the pressure-resistant microfluidic chip is slowly released, releasing and discharging the original pressure inside the chip to avoid damage.

[0022] 4. The microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the invention further includes a temperature control system. The temperature control system comprises a water bath temperature control device, a temperature control jacket, and a quartz wool outer layer. The temperature control jacket is matched with the pressure vessel, and the quartz wool outer layer is placed at the connection between the temperature control jacket and the pressure vessel. The water bath temperature control device achieves liquid circulation cooling by cooling with ethylene glycol antifreeze and injecting it into the temperature control jacket. This invention, by employing ethylene glycol antifreeze circulation cooling and quartz wool outer layer insulation, achieves a wider temperature control range (supporting temperatures from low temperatures to seabed temperatures) and smaller temperature fluctuations.

[0023] 5. In the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the present invention, a camera observes and acquires images of the hydrate reaction inside the pressure-resistant microfluidic chip in real time through a sapphire window. This helps to observe and record the generation and decomposition process of carbon dioxide hydrate in the pressure-resistant microfluidic chip in real time, study the generation and decomposition rate of carbon dioxide hydrate, the influence of different promoters on the stability of carbon dioxide hydrate, explore the microscopic mechanism of carbon dioxide seabed carbon sequestration, and conduct feasibility analysis. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the functional modules of the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the utility model.

[0026] Figure 2 This is a three-dimensional structural schematic diagram of the pressure-resistant microfluidic hydrate reaction system in the microfluidic experimental device for carbon dioxide hydrate carbon sequestration provided in this embodiment of the utility model.

[0027] Figure 3 This is a three-dimensional structural diagram of the pressure-resistant microfluidic chip in the carbon dioxide hydrate carbon encapsulation microfluidic experimental device provided in this embodiment of the utility model.

[0028] Explanation of reference numerals in the attached diagram:

[0029] 1. Microfluidic experimental apparatus for carbon sequestration of carbon dioxide hydrate;

[0030] 11. Pressure-resistant microfluidic hydrate reaction system; 12. Microfluidic injection and pressure control system; 13. Real-time pressure and temperature display system; 14. Gas introduction system; 15. Image acquisition system;

[0031] 111. Pressure-resistant microfluidic chip; 112. Compressor; 113. Pressure vessel; 114. Second metal screw; 115. Rubber screw; 116. Pressure-controlled hydraulic pump; 117. Back pressure valve; 121. CNC injection pump; 122. Pressure-resistant piston container; 123. Pressure valve; 131. Temperature sensor; 132. Pressure sensor; 141. Gas cylinder; 142. Pressure regulating valve; 151. Camera; 152. Camera lens; 153. Ring illumination source;

[0032] 1111, Injection port; 1131, Gas-liquid channel; 1132, Fixing base; 1133, Pressure cap; 1134, First metal screw; 1135, Sapphire window; 1161, Liquid tank; 1211, First digital display screen; 1212, Pressure and flow rate adjustment panel;

[0033] 122a, First container; 122b, Second container; 123a, First inlet valve; 123b, Second inlet valve; 123c, First outlet valve; 123d, Second outlet valve. Detailed Implementation

[0034] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0036] It is understood that the singular forms “a,” “an,” and “the” used in this application may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof.

[0037] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0038] In this utility model, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this utility model and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this utility model according to the specific circumstances.

[0039] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this utility model based on the specific circumstances.

[0040] Please see Figure 1 As shown, this utility model embodiment provides a microfluidic experimental device 1 for carbon dioxide hydrate carbon sequestration. The microfluidic experimental device 1 for carbon dioxide hydrate carbon sequestration includes a pressure-resistant microfluidic hydrate reaction system 11, a microfluidic injection and pressure control system 12, a pressure and temperature real-time display system 13, a gas introduction system 14, and an image acquisition system 15.

[0041] The microfluidic injection and pressure control system 12, the real-time pressure and temperature display system 13, and the gas introduction system 14 are all connected to the pressure-resistant microfluidic hydrate reaction system 11. The microfluidic injection and pressure control system 12 quantitatively injects liquid into the pressure-resistant microfluidic hydrate reaction system 11 and adjusts the pressure in the pressure-resistant microfluidic hydrate reaction system 11 in real time. The real-time pressure and temperature display system 13 detects the temperature and pressure in the pressure-resistant microfluidic hydrate reaction system 11 in real time. The gas introduction system 14 introduces gas into the pressure-resistant microfluidic hydrate reaction system 11. The image acquisition system 15 observes and acquires images of the hydrate reaction inside the pressure-resistant microfluidic hydrate reaction system 11 in real time.

[0042] Please combine Figures 1-3 As shown, specifically, the pressure-resistant microfluidic hydrate reaction system 11 includes a pressure-resistant microfluidic chip 111, a pressure plate 112, and a pressure vessel 113. The pressure plate 112 fixes the pressure-resistant microfluidic chip 111 in the pressure vessel 113. The pressure-resistant microfluidic chip 111 is a glass microfluidic chip with four injection holes 1111. The pressure vessel 113 is provided with four gas-liquid channels 1131, and the four injection holes 1111 correspond to the four gas-liquid channels 1131. The four gas-liquid channels 1131 include three injection channels and one liquid outlet channel. The microfluidic injection and pressure control system 12 and the gas inlet system 14 are connected to the three injection channels.

[0043] like Figure 3 As shown, preferably, the pressure-resistant microfluidic chip 111 is a high-pressure resistant four-hole square glass microfluidic chip. The average internal channel diameter of the pressure-resistant microfluidic chip 111 is less than 100 micrometers. It is made of two etched glass substrates bonded together, leaving the channel structure in the middle and the surrounding area is bonded and sealed.

[0044] Specifically, the pressure vessel 113 includes a fixed base 1132 and a pressure cover 1133. A gas-liquid channel 1131 is disposed on the fixed base 1132. The fixed base 1132 and the pressure cover 1133 are fixed by fourteen first metal screws 1134.

[0045] Preferably, the pressure plate 112 is an eight-hole metal disc pressure plate. The pressure plate 112 is used to fix the pressure-resistant microfluidic chip 111 in the pressure vessel 113 by four second metal screws 114 and four rubber screws 115. It can be understood that before operation begins, the four injection holes 1111 on the pressure-resistant microfluidic chip 111 need to be aligned with the four gas-liquid channels 1131 of the pressure vessel 113. The pressure plate 112 is placed on the pressure-resistant microfluidic chip 111, and the four second metal screws 114 are screwed into the pressure vessel 113 to fix the pressure plate 112 and the pressure vessel 113. Then, the rubber screws 115 are screwed into the pressure plate 112 to fix the pressure-resistant microfluidic chip 111 in the pressure vessel 113. Finally, the pressure cap 1133 is covered and fixed with fourteen first metal screws 1134.

[0046] This invention, by setting four gas-liquid channels 1131 in the confined pressure vessel 113 in conjunction with four injection holes 1111 in the pressure-resistant microfluidic chip 111, creates multiphase flow in the channels of the pressure-resistant microfluidic chip 111. This solves the problem that existing microfluidic devices cannot simulate the multi-channel seepage characteristics of porous media in real sediments in simulated seabed sediment environments, resulting in a single CO2 transport path and systematic deviations between experimental data and real-world scenarios for key parameters such as hydrate formation rate and sequestration space distribution. It enables two-phase displacement flow of gas and liquid in hydrates to achieve a better gas-liquid mixing ratio and allows for simultaneous injection of liquid and gas through multiple channels, which is more in line with the complex environment of seabed sediments and increases the diversity and realism of experiments.

[0047] Please continue reading. Figure 1 As shown, specifically, the microfluidic injection and pressure control system 12 includes a CNC injection pump 121 and two pressure-resistant piston containers 122. The pressure-resistant piston containers 122 are filled with liquid, and pressure valves 123 are installed at both the inlet and outlet. The CNC injection pump 121 controls the pressure-resistant piston containers 122 to inject liquid into the pressure-resistant microfluidic chip 11 through three injection channels.

[0048] More specifically, the pressure-resistant piston container 122 includes a first container 122a and a second container 122b, and the pressure valve 123 includes a first inlet valve 123a, a second inlet valve 123b, a first outlet valve 123c, and a second outlet valve 123d. The first inlet valve 123a is installed at the inlet of the first container 122a, and the first outlet valve 123c is installed at the outlet of the first container 122a. The second inlet valve 123b is installed at the inlet of the second container 122b, and the second outlet valve 123d is installed at the outlet of the second container 122b.

[0049] In this embodiment of the invention, the maximum pump pressure of the CNC injection pump 121 is 40 MPa. It can be understood that the CNC injection pump 121 uses an electronic pump to compress deionized water and introduce it into the pressure-resistant piston container 122, generating hydraulic pressure to push the piston in the pressure-resistant piston container 122, thus introducing the stored experimental reagents into the pressure-resistant microfluidic chip 111 through the injection channel.

[0050] More specifically, the CNC injection pump 121 includes a first digital display screen 1211 and a pressure and flow rate adjustment panel 1212, the pressure and flow rate adjustment panel 1212 being used to adjust the pressure of the pressure-resistant piston container 122 and the flow rate of the liquid injection, and the first digital display screen 1211 being used to display the pressure and flow rate readings.

[0051] This invention solves the problem that existing microfluidic devices, due to their single liquid storage tube design, limit the dynamic interaction research of multiphase fluids (such as CO2-seawater-methane coexistence systems), and cannot simulate the multiphase interface oscillation effects caused by tidal activity and seabed seepage, resulting in a lack of understanding of the sediment-hydrate-fluid coupling mechanism. It can achieve real-time liquid control and injection, as well as multiple liquid displacement, improving the utilization efficiency and experimental diversity of the pressure-resistant microfluidic chip 111.

[0052] Please continue reading. Figure 1 As shown, specifically, the real-time pressure and temperature display system 13 includes several temperature sensors 131, several pressure sensors 132, a data collection unit (not shown), and a second digital display screen (not shown). The temperature sensors 131 and pressure sensors 132 are used to monitor the temperature and pressure of the confined pressure vessel 113 in real time. The data collection unit collects temperature and pressure data, and the second digital display screen can display the temperature and pressure readings in real time with an accuracy to one decimal place.

[0053] Specifically, the gas inlet system 14 includes a gas cylinder 141 and a pressure regulating valve 142. The gas cylinder 141 is filled with gas and is connected to three injection channels. The pressure regulating valve 142 adjusts the speed at which the gas in the gas cylinder 141 is introduced into the pressure-resistant microfluidic chip 111 to control the pressure of the hydrate reaction.

[0054] It's understandable that gas cylinder 141 is typically filled with carbon dioxide, with a maximum pressure of 15 MPa. Of course, it can be replaced with other gases depending on the experiment, including but not limited to mixtures of methane, hydrogen, etc.

[0055] Please continue to combine Figure 1 and Figure 2As shown, specifically, the pressure vessel 113 also includes a sapphire window 1135, and the image acquisition system 15 includes a camera 151, a camera lens 152, and a ring illumination source 153. The ring illumination source 153 is placed on one side of the pressure vessel 113, while the camera 151 and camera lens 152 are placed on opposite sides of the pressure vessel 113. The camera lens 152 is used to adjust the magnification. The camera 151 observes and acquires images of the hydrate reaction inside the pressure-resistant microfluidic chip 111 in real time through the sapphire window 1135. This setup facilitates real-time observation and recording of the formation and decomposition process of carbon dioxide hydrate in the pressure-resistant microfluidic chip 111, allowing for the study of the formation and decomposition rate of carbon dioxide hydrate, the influence of different promoters on the stability of carbon dioxide hydrate, exploration of the microscopic mechanism of carbon dioxide sequestration on the seabed, and feasibility analysis.

[0056] In this embodiment of the invention, the height and angle of the camera 151 and the camera lens 152 can be adjusted, and this embodiment of the invention does not limit the scope of the invention.

[0057] In this embodiment of the invention, the magnification range of the camera lens 152 is 10x to 50x.

[0058] In this embodiment of the invention, the brightness of the ring-shaped lighting source 153 is adjustable. Specifically, it is adjusted via a knob.

[0059] Furthermore, the microfluidic experimental device 1 for carbon dioxide hydrate carbon sequestration also includes a temperature control system (not shown), which comprises a water bath temperature control device, a temperature control jacket, and a quartz wool outer layer. The temperature control jacket is matched with the pressure vessel 113, and the quartz wool outer layer is placed at the connection between the temperature control jacket and the pressure vessel 113. The water bath temperature control device achieves liquid circulation cooling by cooling with ethylene glycol antifreeze and injecting it into the temperature control jacket. This invention, by employing ethylene glycol antifreeze circulation cooling and quartz wool outer layer insulation, achieves a wider temperature control range (supporting temperatures from low temperatures to seabed temperatures) and smaller temperature fluctuations.

[0060] It is understandable that the water bath temperature control device uses a specific ratio of ethylene glycol solution and water as refrigerant to achieve a freezing point far below zero degrees Celsius. The required temperature is reached under the cooling of the CNC refrigeration machine, and then the refrigerant is introduced into the temperature control jacket through the refrigerant pipeline to achieve cooling of the outside of the device.

[0061] Please continue reading. Figure 1 As shown, specifically, the pressure-resistant microfluidic hydrate reaction system 11 also includes a confining pressure hydraulic pump 116 and a back pressure valve 117, both of which are connected to the confining pressure vessel 113.

[0062] A confining pressure hydraulic pump 116 is connected to a liquid tank 1161. The confining pressure hydraulic pump 116 is used to provide a protective pressure, i.e., a confining pressure, to the cavity of the confining pressure vessel 113, and this protective pressure is greater than the pressure of the pressure-resistant microfluidic chip 111. Preferably, the confining pressure hydraulic pump 116 can adjust the magnitude of the confining pressure in real time according to the pressure change inside the pressure-resistant microfluidic chip 111, thereby ensuring that the confining pressure is always higher than the internal pressure of the pressure-resistant microfluidic chip 111 during the experiment.

[0063] The back pressure valve 117 is used to regulate the pressure difference between the internal and external environments of the pressure-resistant microfluidic chip 111, ensuring that the external environmental pressure of the pressure-resistant microfluidic chip 111 is greater than the internal environmental pressure. Simultaneously, it relieves pressure on the pressure-resistant microfluidic chip 111 at the end of use. Specifically, the pressure in the back pressure valve 117 is slowly reduced by adjusting the lever, thus gradually releasing the pressure in the pressure-resistant microfluidic chip 111.

[0064] More specifically, the confining pressure (protective pressure) is 1-2 MPa higher than the pressure of the pressure-resistant microfluidic chip 111. The back pressure valve 117 controls the pressure difference between the internal and external environments of the pressure-resistant microfluidic chip 111 to be 1 MPa, that is, the external environment pressure of the pressure-resistant microfluidic chip 111 is 1 MPa higher than the internal environment pressure.

[0065] This invention, by incorporating a confining pressure hydraulic pump 116, provides a protective pressure to the cavity of the confining pressure vessel 113 that exceeds the internal pressure of the pressure-resistant microfluidic chip 111, preventing damage to the pressure-resistant microfluidic hydrate reaction system 11 due to excessive internal pressure during operation. Furthermore, by incorporating a backpressure valve 117, the external environmental pressure of the pressure-resistant microfluidic chip 111 is adjusted to be greater than the internal environmental pressure, effectively acting as a shut-off valve to prevent gas and liquid from escaping from the chip during operation. Simultaneously, at the end of use, the pressure in the pressure-resistant microfluidic chip 111 is slowly released, allowing the original pressure inside the chip to be discharged through the liquid outlet channel, thus preventing damage to the chip.

[0066] The following describes in detail Embodiment 1 of this utility model.

[0067] Using a microfluidic injection and pressure control system 12, liquid from the two pressure-resistant piston containers 122 is introduced into the pressure-resistant microfluidic chip 111 by adjusting the reading on the CNC injection pump 121, keeping the connecting valves open. Temperature sensors 131 and 132 in the real-time pressure and temperature display system 13 are connected to the confined pressure vessel 113 to achieve real-time monitoring of the temperature and pressure of the confined pressure vessel 113. A confined pressure hydraulic pump 116 provides a protective pressure to the cavity of the confined pressure vessel 113. This protective pressure is always greater than the internal pressure of the pressure-resistant microfluidic chip 111, with a difference of 1–2 MPa, to prevent excessive internal pressure during use, which could damage the pressure-resistant microfluidic chip 111. The confined pressure hydraulic pump 116 can adjust the confined pressure in real time according to changes in the internal pressure of the pressure-resistant microfluidic chip 111, ensuring that the confined pressure remains higher than the internal pressure of the pressure-resistant microfluidic chip 111 throughout the experiment. A pressure difference is created between the internal and external environments of the pressure-resistant microfluidic chip 111 by using a back pressure valve 117. This pressure difference is maintained at about 1 MPa to prevent gas and liquid from escaping from the inside of the pressure-resistant microfluidic chip 111 during device operation. When the device is no longer in use, the pressure of the back pressure valve 117 is slowly reduced by adjusting the lever to slowly relieve the pressure in the pressure-resistant microfluidic chip 111.

[0068] During operation, while the CNC syringe pump 121 injects the accelerator solution into the pressure-resistant microfluidic chip 111 at a flow rate of 8 ml / min, the pressure regulating valve 142 of the gas inlet system 14 is adjusted to introduce carbon dioxide gas from the gas cylinder 141 into the pressure-resistant microfluidic chip 111. The gas-liquid distribution in the pressure-resistant microfluidic chip 111 is observed through a sapphire window 1135 using the camera 151 and camera lens 152 in the image acquisition system 15, along with a ring illumination source 153. After verifying good airtightness, the external water bath is used for cooling to achieve the required temperature and pressure conditions of 6 MPa and 276 K, generating carbon dioxide hydrate. The camera lens 152 is then adjusted to magnify 30 times and fixed at a fixed focal length, and video recording and observation are performed using the camera 151.

[0069] Embodiment 2 of this utility model is described in detail below.

[0070] Compared to Example 1, Example 2 uses two pressure-resistant piston containers 122 filled with different experimental reagents, such as reagent A and reagent B, to achieve a displacement effect. The first container 122a contains reagent A, and the second container 122b contains reagent B. The first inlet valve 123a of the first container 122a is opened, and reagent A is introduced into the pressure-resistant microfluidic chip 111 using a CNC syringe pump 121. The experimental operation in Example 1 is repeated to conduct research on carbon dioxide hydrate. After the study, the internal environment and all environmental variables are kept constant. Then, the first inlet valve 123a is closed, and the second inlet valve 123b of the second container 122b is opened. Reagent B is introduced into the pressure-resistant microfluidic chip 111 using the CNC syringe pump 121. The experimental operation in Example 1 is repeated to conduct research on carbon dioxide hydrate. The method described above helps to more effectively compare the effects of two different experimental reagents on the formation and decomposition of carbon dioxide hydrate in experimental studies using a single variable.

[0071] The microfluidic experimental device 1 for carbon dioxide hydrate carbon sequestration described in this utility model has wide application value in several key fields, and specific application scenarios include the following:

[0072] 1. Assessment of Carbon Dioxide Seafloor Geological Storage: This device can simulate the pore structure and environmental conditions (such as high pressure and low temperature) of porous media in seafloor sediments to study the formation rate, spatial distribution, and long-term stability of carbon dioxide hydrates in the pores, and to assess storage capacity and leakage risk. Simultaneously, it can optimize the combined exploitation-storage strategy of "carbon dioxide replacing methane hydrates" and verify replacement efficiency and reservoir structural integrity.

[0073] 2. Development of hydrate-based carbon capture technology: In the field of carbon neutralization, this device can perform high-throughput screening of chemical additives (such as surfactants and tetrahydrofuran) that promote the formation of carbon dioxide hydrates, and test the kinetics of hydrate formation under different temperature and pressure conditions, providing an experimental platform for low-energy carbon capture technology. Furthermore, it can also study the selective hydration separation effect of carbon dioxide in mixed systems containing impurity gases (such as nitrogen and oxygen), supporting the design of carbon dioxide purification processes in industrial waste gases.

[0074] 3. Carbon dioxide flooding and synergistic storage technology: In oilfield flooding projects, this device is used to analyze the migration patterns of carbon dioxide in reservoir pores and the synergistic mechanism of hydrate storage, optimize flooding parameters (such as injection pressure and temperature), and simultaneously evaluate the stability of hydrate storage, so as to achieve the dual goals of improving flooding efficiency and reducing carbon emissions.

[0075] These application scenarios cover energy development, carbon neutrality, industrial safety and environmental technology, reflecting the dual value of this carbon dioxide hydrate carbon sequestration microfluidic experimental device 1 in basic research and engineering practice, and can provide core experimental tools for the industrialization of carbon dioxide hydrate related technologies.

[0076] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A carbon dioxide hydrate carbon sequestration microfluidic experimental device, characterized by: The carbon dioxide hydrate carbon sequestration microfluidic experimental device comprises a pressure-resistant microfluidic hydrate reaction system, a trace fluid injection and pressure control system, a pressure and temperature real-time display system and a gas feeding system, the trace fluid injection and pressure control system, the pressure and temperature real-time display system and the gas feeding system are connected with the pressure-resistant microfluidic hydrate reaction system; The trace fluid injection and pressure control system quantitatively injects liquid into the pressure-resistant microfluidic hydrate reaction system and adjusts the pressure in the pressure-resistant microfluidic hydrate reaction system in real time, the pressure and temperature real-time display system detects the temperature and pressure in the pressure-resistant microfluidic hydrate reaction system in real time, and the gas feeding system feeds gas into the pressure-resistant microfluidic hydrate reaction system; The pressure-resistant microfluidic hydrate reaction system comprises a pressure-resistant microfluidic chip, a pressing sheet and a surrounding pressure kettle, the pressing sheet fixes the pressure-resistant microfluidic chip in the surrounding pressure kettle; the pressure-resistant microfluidic chip is a glass microfluidic chip with four injection holes, the surrounding pressure kettle is provided with four gas-liquid channels, the four injection holes correspond to the four gas-liquid channels, and the four gas-liquid channels comprise three injection channels and one liquid outlet channel.

2. The carbon dioxide hydrate carbon sequestration microfluidic experimental device of claim 1, wherein: The trace fluid injection and pressure control system comprises a numerical control injection pump and two pressure-resistant piston containers, the pressure-resistant piston containers are filled with liquid, and the numerical control injection pump controls the pressure-resistant piston containers to inject liquid into the pressure-resistant microfluidic chip through the three injection channels.

3. The carbon dioxide hydrate carbon sequestration microfluidic experimental device of claim 1, wherein: The gas feeding system comprises a gas cylinder and a pressure regulating valve, the gas cylinder is filled with gas, the gas cylinder is communicated with the three injection channels, and the pressure regulating valve adjusts the speed of the gas in the gas cylinder feeding into the pressure-resistant microfluidic chip to control the pressure of the hydrate reaction.

4. The carbon dioxide hydrate carbon sequestration microfluidic experiment device of claim 1, wherein: The pressure-resistant microfluidic hydrate reaction system further comprises a surrounding pressure liquid control pump and a back pressure valve, the surrounding pressure liquid control pump and the back pressure valve are connected with the surrounding pressure kettle, the surrounding pressure liquid control pump is used for providing a protection pressure for the cavity of the surrounding pressure kettle, and the protection pressure is greater than the pressure of the pressure-resistant microfluidic chip; the back pressure valve is used for adjusting the pressure difference between the internal and external environments of the pressure-resistant microfluidic chip and making the external environment pressure of the pressure-resistant microfluidic chip greater than the internal environment pressure of the pressure-resistant microfluidic chip, and simultaneously discharging pressure from the pressure-resistant microfluidic chip at the end of use.

5. The carbon dioxide hydrate carbon sequestration microfluidic experiment device of claim 4, wherein: The protection pressure is 1-2 Mpa higher than the pressure of the pressure-resistant microfluidic chip.

6. The carbon dioxide hydrate carbon sequestration microfluidic experiment device of claim 4, wherein: The back pressure valve controls the pressure difference between the internal and external environments of the pressure-resistant microfluidic chip to be 1 Mpa.

7. The carbon dioxide hydrate carbon sequestration microfluidic experimental device of claim 1, wherein: The carbon dioxide hydrate carbon sequestration microfluidic experimental device further comprises a temperature control system, the temperature control system comprises a water bath temperature control device, a temperature control jacket and a quartz cotton outer layer; The temperature control jacket is matched with the surrounding pressure kettle, the quartz cotton outer layer is arranged at the connection position of the temperature control jacket and the surrounding pressure kettle, and the water bath temperature control device realizes liquid circulation cooling by cooling and injecting ethylene glycol antifreeze liquid into the temperature control jacket.

8. The carbon dioxide hydrate carbon sequestration microfluidic experimental device of claim 1, wherein: The surrounding pressure kettle comprises a fixed base and a pressure cover, the gas-liquid channels are arranged on the fixed base, and the fixed base and the pressure cover are fixed by fourteen first metal screws.

9. The carbon dioxide hydrate carbon sequestration microfluidic experiment device of claim 8, wherein: The carbon dioxide hydrate carbon sequestration microfluidic experiment device further comprises an image acquisition system, the confining pressure vessel further comprises a sapphire window, and the image acquisition system comprises a camera, a camera lens and an annular illumination light source. The annular illumination light source is arranged on one side of the confining pressure vessel, the camera and the camera lens are arranged on the opposite side of the confining pressure vessel, the camera lens is used for adjusting the magnification, and the camera is used for observing and acquiring the image of the hydrate reaction in the pressure-resistant microfluidic chip in real time through the sapphire window.

10. The carbon dioxide hydrate carbon sequestration microfluidic experimental device of claim 1, wherein: The tablet is an eight-hole metal disc tablet, and the tablet is used for fixing the pressure-resistant microfluidic chip in the confining pressure vessel through four second metal screws and four rubber screws.

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