Impurity-containing CO2 phase change demonstration experiment device

Abstract

The invention relates to the technical field of phase change observation, in particular to an impurity-containing CO2 phase change demonstration experiment device. The impurity-containing CO2 phase state change demonstration experiment device comprises a visible high-pressure reaction kettle, a carbon dioxide filling system, an impurity gas filling system and a phase state control system, the high-pressure reaction kettle is provided with a filling port, and the impurity gas filling system and the phase state control system are connected with the filling port. The phase state control system is arranged on the high-pressure reaction kettle and is used for heating and refrigerating the high-pressure reaction kettle so as to control the phase state of the added carbon dioxide, and the high-pressure reaction kettle is provided with a pressure relief opening which can be opened or closed. The device has the advantages of being reasonable in structural design, capable of visually and clearly displaying phase characteristics of CO2 or CO2 containing impurities and characteristics and laws of phase state changes of the CO2 or the CO2 containing impurities, simple in device and easy to operate.

Description

Technical Field

[0001] The invention relates to the technical field of phase change observation, and in particular to a demonstration experimental device for phase change of impurity-containing CO2. Background Art

[0002] Due to the special physical properties of CO2 itself, its phase characteristics are complex, including gas, liquid, solid, dense phase and supercritical state. The supercritical CO2 physical properties have the characteristics of high density of liquid and low viscosity of gas, and other impurity gases such as O2 and N2 have a great influence on the phase characteristics of CO2. The complex physical properties and phase change laws of CO2 make ordinary people have no accurate and intuitive understanding of CO2. Because the supercritical point of pure CO2 is 31.1℃, 7.38MPa, it belongs to the high temperature and high pressure state, and the phase change needs to control its temperature and pressure to change accurately near the critical point, and how to intuitively characterize gaseous, liquid and supercritical CO2 is a difficult problem.

[0003] At present, there are few technologies in China for demonstrating CO2 phase changes, and there are no related devices that are streamlined, simple to operate, and easy to observe. There are no unified design standards and specifications for phase change observation equipment.

[0004] Based on this, it is necessary to develop an experimental device for demonstrating the phase change of CO2 containing impurities to overcome the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a demonstration experimental device for phase change of CO2 containing impurities, which effectively overcomes the defects of the prior art.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] A demonstration experimental device for phase change of impure CO2 includes a visible high-pressure reactor, a carbon dioxide filling system, an impurity gas filling system and a phase control system. The high-pressure reactor is provided with a filling port. The impurity gas filling system and the phase control system are respectively connected to the filling port. The phase control system is installed in the high-pressure reactor and is used for heating and cooling the high-pressure reactor to control the phase of the added carbon dioxide. The high-pressure reactor is provided with a pressure relief port that can be opened or closed.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, the high-pressure reactor is a transparent reactor resistant to high temperature and high pressure.

[0010] Furthermore, the carbon dioxide filling system includes a first weighing device and a carbon dioxide gas cylinder and a compressor respectively mounted on the first weighing device, and the gas outlet of the carbon dioxide gas cylinder is sequentially connected to the inlet, outlet and filling port of the compressor through pipelines.

[0011] Furthermore, the impurity gas filling system includes a second weighing device and impurity gas cylinders respectively mounted on the second weighing devices, and the gas outlets of the impurity gas cylinders are connected to the filling port via pipelines.

[0012] Furthermore, the filling port is connected to a three-way valve, and the outlet of the compressor and the gas outlet of the impurity gas cylinder are respectively connected to two interfaces of the three-way valve through pipelines.

[0013] Furthermore, spheres and cuboids with different densities are placed in the high-pressure reactor, and the density of the spheres is greater than the density of carbon dioxide gas and less than the density of supercritical carbon dioxide, and the density of the cuboids is greater than the density of supercritical carbon dioxide and less than the density of liquid carbon dioxide.

[0014] Furthermore, the phase control system includes an electric heating belt and an annular cold chamber, the electric heating belt is wrapped around the outer wall of the high-pressure reactor, the cold chamber is sleeved outside the high-pressure reactor, the electric heating belt is sandwiched between the high-pressure reactor and the cold chamber, and the side wall of the cold chamber is provided with a cold air inlet and a cold air outlet.

[0015] Furthermore, it also includes a data acquisition system, which includes a temperature detector, a pressure detector and a main engine. The top wall of the high-pressure reactor is provided with a temperature detection port and a pressure detection port. The temperature detector and the pressure detector are respectively installed at the temperature detection port and the pressure detection port. The temperature detector, the pressure detector and the electric heating belt are respectively connected to the main engine.

[0016] Furthermore, the temperature detector is a thermocouple, and the pressure detector is an electronic pressure gauge.

[0017] Furthermore, a vent is provided at the top of the high-pressure reactor, and a manual vent valve is installed at the vent.

[0018] The beneficial effects of the present invention are: reasonable structural design, capable of intuitively and clearly displaying the phase characteristics of CO2 or impurity-containing CO2 and the characteristics and laws of its phase state change, and the device is simple and easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the experimental device for demonstrating the phase change of impurity-containing CO2 of the present invention.

[0020] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0021] 1. High-pressure reactor; 21. First weighing device; 22. Carbon dioxide cylinder; 23. Compressor; 31. Second weighing device; 32. Impurity gas cylinder; 41. Electric heating belt; 42. Cold storage; 51. Temperature detector; 52. Pressure detector; 61. Manual vent valve. DETAILED DESCRIPTION

[0022] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0023] Example

[0024] like Figure 1 As shown, the impurity-containing CO2 phase change demonstration experimental device of this embodiment includes a visible high-pressure reactor 1, a carbon dioxide filling system, an impurity gas filling system and a phase control system. The high-pressure reactor 1 is provided with a filling port, and the impurity gas filling system and the phase control system are respectively connected to the filling port. The phase control system is installed in the high-pressure reactor 1 and is used to heat and cool the high-pressure reactor 1 to control the phase of the added carbon dioxide. The high-pressure reactor 1 is provided with a pressure relief port that can be opened or closed.

[0025] The impurity-containing CO2 phase change demonstration experimental device of this embodiment can intuitively and conveniently observe the CO2 phase change process through the visible high-pressure reactor 1. After the preparatory work is done, the impurities can be preferentially filled through the impurity gas filling system in a low-pressure state, and CO2 is injected into the reactor at high pressure through the carbon dioxide filling system, and the CO2 filling amount (weight) is measured synchronously. Then cooperate with the phase control system to adjust the temperature in the high-pressure reactor 1 to achieve the purpose of controlling the CO2 phase. The overall structural design is reasonable, and the phase characteristics of CO2 or impurity-containing CO2 and the characteristics and laws of its phase change can be intuitively and clearly displayed. The device is simple and easy to operate.

[0026] In this embodiment, the high-pressure reactor 1 is a transparent reactor resistant to high temperature and high pressure, and can be made of a transparent polymer material resistant to high temperature and high pressure.

[0027] As a preferred embodiment, the carbon dioxide filling system includes a first weighing device 21 and a carbon dioxide cylinder 22 and a compressor 23 respectively mounted on the first weighing device 21, and the gas outlet of the carbon dioxide cylinder 22 is sequentially connected to the inlet, outlet and filling port of the compressor 23 through a pipeline.

[0028] In the above embodiment, carbon dioxide is injected into the high-pressure reactor 1 under high pressure through the compressor 23, and the weight change of the carbon dioxide cylinder 22 is weighed by the first weighing device 21 throughout the process, so as to monitor the added weight of carbon dioxide during the filling process, and combine the theoretical calculation of the mass required for filling, and the high-pressure reactor 1 can be accurately controlled by heating to reach the specified temperature and pressure.

[0029] The first weighing device 21 is a platform scale of a suitable model currently available on the market.

[0030] As a preferred embodiment, the impurity gas filling system includes a second weighing device 31 and impurity gas cylinders 32 respectively mounted on the second weighing devices 31, and the gas outlets of the impurity gas cylinders 32 are connected to the filling port via pipelines.

[0031] In the above embodiment, the impurity gas cylinder 32 is self-pressurized and filled by the pressure of its own cylinder body, presenting low-pressure filling. During the filling process, the filling weight can be monitored in real time by the second weighing device 31.

[0032] The second weighing device 31 is a platform scale of a suitable model currently available on the market.

[0033] In this embodiment, a three-way valve is connected to the filling port, and the outlet of the compressor 23 and the gas outlet of the impurity gas cylinder 32 are respectively connected to the two interfaces of the three-way valve through pipelines, so as to facilitate the connection of the impurity gas and carbon dioxide injection pipelines with the filling port.

[0034] As a preferred embodiment, spheres and cuboids with different densities are placed in the high-pressure reactor 1, and the density of the spheres is greater than the density of carbon dioxide gas and less than the density of supercritical carbon dioxide, and the density of the cuboids is greater than the density of supercritical carbon dioxide and less than the density of liquid carbon dioxide.

[0035] In the above embodiment, two objects with different densities are placed in the autoclave 1, one is a sphere and the other is a cube, which can vividly show the phase transformation of CO2 between gas, liquid and supercritical states. The densities of the two objects should meet the following relationship:

[0036]

[0037] During the carbon dioxide filling process, the range is selected based on the maximum weight of the CO2 used and the carbon dioxide cylinder 22 when fully filled. The range should be such that the individual weighing of all cylinders in a fully filled state does not exceed the range. Then according to the law of conservation of mass:

[0038] M 加注需要的质量 =M 达到指定工况后系统内的质量

[0039] Calculate the mass of CO2 and impurities under the set working conditions to obtain the mass of CO2 required by the high-pressure reactor 1 in the experiment. Knowing the volume (V) of the high-pressure reactor 1, the temperature and pressure under the working conditions, obtain the mixed density (ρ 混合_工况 ) and the mass fraction of CO2 and impurities (α CO2 and α 杂质 ) and then calculate the mass of CO2 and impurities required for filling.

[0040] The mass of CO2 can be calculated by the following formula:

[0041] M CO2 =α CO2 ρ 混合_工况 V

[0042] The required mass of impurities can be calculated by the following formula:

[0043] M 杂质 =α 杂质 ρ 混合_工况 V

[0044] The mixed density of CO2 and impurities under temperature and pressure is calculated by GERG-2008 high-precision gas state equation. After preparation, impurities can be injected by self-pressurization at low pressure first, CO2 can be injected into high-pressure reactor 1 at high pressure, and the weight change of CO2 can be monitored in real time. At the same time, the purpose of controlling the phase state can be achieved through the phase state control system.

[0045] As a preferred embodiment, the phase control system includes an electric heating belt 41 and an annular cold chamber 42. The electric heating belt 41 is wrapped around the outer wall of the high-pressure reactor 1. The cold chamber 42 is sleeved outside the high-pressure reactor 1. The electric heating belt 41 is sandwiched between the high-pressure reactor 1 and the cold chamber 42. The side wall of the cold chamber 42 is provided with a cold air inlet and a cold air outlet.

[0046] In the above embodiment, the phase control system is composed of electric heating and cold air bath, which are respectively responsible for heating or cooling CO2 to achieve the purpose of controlling the phase state. The electric heating belt 41 is evenly wrapped around the outside of the high-pressure reactor 1. There is an openable cylindrical shell (that is, the cold warehouse 42) on the outside of the high-pressure reactor 1, which wraps the high-pressure reactor 1 wrapped with the electric heating belt 41. The cold warehouse 42 has an inlet and an outlet, the inlet is connected to the cold air, and the outlet can be directly emptied to the outside. The cold air source uses the vortex tube principle, uses high-pressure air to generate cold air, and forms a low-temperature circulation around the high-pressure reactor to achieve the purpose of cooling.

[0047] As a preferred embodiment, it also includes a data acquisition system, which includes a temperature detector 51, a pressure detector 52 and a main engine. The top wall of the high-pressure reactor 1 is provided with a temperature detection port and a pressure detection port. The temperature detector 51 and the pressure detector 52 are respectively installed at the temperature detection port and the pressure detection port. The temperature detector 51, the pressure detector 52 and the electric heating belt 41 are respectively connected to the main engine.

[0048] In the above embodiment, the electric heating belt 41 is evenly wound around the outside of the autoclave 1, and together with the temperature detector 51, it forms a PID control to feedback-regulate the heating power, increase the heating power in the initial stage of heating to shorten the heating time, and reduce the heating power when approaching the set temperature to prevent overheating and overpressure. This design not only improves the heating efficiency and saves the heating time, but also avoids the over-temperature and overpressure in the autoclave 1 caused by excessive power. At the same time, the pressure detector 52 is used to monitor the pressure state of CO2 in the autoclave 1, and the temperature and pressure information are displayed in real time on the CO2 phase diagram on the screen of the host, which shows the phase change process of supercritical CO2 in a more theoretical way.

[0049] In this embodiment, the temperature detector 51 adopts a thermocouple of an adapted model, and the pressure detector 52 adopts an electronic pressure gauge of an adapted model.

[0050] As a preferred embodiment, a vent is provided at the top of the high-pressure reactor 1, and a manual vent valve 61 is installed at the vent.

[0051] In the above embodiment, the high-pressure reactor 1 is provided with a manual vent valve 61, which can demonstrate the effect of CO2 leakage on the phase change during the throttling process and the phenomenon of dry ice generation at low temperature during injection, and can also be artificially emptied in the case of overfilling or overheating to achieve the purpose of specified temperature and pressure.

[0052] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0053] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0054] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0057] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A demonstration experimental device for phase change of CO2 containing impurities, characterized in that: The invention comprises a visible high-pressure reactor (1), a carbon dioxide filling system, an impurity gas filling system and a phase control system. The high-pressure reactor (1) is provided with a filling port. The impurity gas filling system and the phase control system are respectively connected to the filling port. The phase control system is installed in the high-pressure reactor (1) and is used to heat and cool the high-pressure reactor (1) to control the phase of the added carbon dioxide. The high-pressure reactor (1) is provided with a pressure relief port that can be opened or closed.

2. The impurity-containing CO2 phase change demonstration experimental device according to claim 1 is characterized in that: The high-pressure reactor (1) is a transparent reactor resistant to high temperature and high pressure.

3. The impurity-containing CO2 phase change demonstration experimental device according to claim 1 is characterized in that: The carbon dioxide filling system comprises a first weighing device (21) and a carbon dioxide gas cylinder (22) and a compressor (23) respectively mounted on the first weighing device (21); the gas outlet of the carbon dioxide gas cylinder (22) is sequentially connected to the inlet, outlet and filling port of the compressor (23) through pipelines.

4. The experimental device for demonstrating phase change of impurity-containing CO2 according to claim 3 is characterized in that: The impurity gas filling system comprises a second weighing device (31) and impurity gas cylinders (32) respectively mounted on the second weighing devices (31), and the gas outlets of the impurity gas cylinders (32) are connected to the filling port via pipelines.

5. The experimental device for demonstrating phase change of CO2 containing impurities according to claim 4 is characterized in that: The filling port is connected to a three-way valve, and the outlet of the compressor (23) and the gas outlet of the impurity gas cylinder (32) are respectively connected to two interfaces of the three-way valve through pipelines.

6. The experimental device for demonstrating phase change of impurity-containing CO2 according to claim 1, characterized in that: A sphere and a cuboid with different densities are placed in the high-pressure reactor (1), and the density of the sphere is greater than the density of carbon dioxide gas but less than the density of supercritical carbon dioxide, while the density of the cuboid is greater than the density of supercritical carbon dioxide but less than the density of liquid carbon dioxide.

7. A demonstration experimental device for phase change of impurity-containing CO2 according to any one of claims 1 to 6, characterized in that: The phase control system comprises an electric heating belt (41) and an annular cold chamber (42); the electric heating belt (41) is wrapped around the outer wall of the high-pressure reactor (1); the cold chamber (42) is sleeved outside the high-pressure reactor (1); the electric heating belt (41) is sandwiched between the high-pressure reactor (1) and the cold chamber (42); and a cold air inlet and a cold air outlet are provided on the side wall of the cold chamber (42).

8. The impurity-containing CO2 phase change demonstration experimental device according to claim 7 is characterized in that: The invention also comprises a data acquisition system, wherein the data acquisition system comprises a temperature detector (51), a pressure detector (52) and a host computer. The top wall of the high-pressure reactor (1) is provided with a temperature detection port and a pressure detection port. The temperature detector (51) and the pressure detector (52) are respectively installed at the temperature detection port and the pressure detection port. The temperature detector (51), the pressure detector (52) and the electric heating belt (41) are respectively connected to the host computer.

9. The experimental device for demonstrating phase change of CO2 containing impurities according to claim 8, characterized in that: The temperature detector (51) is a thermocouple, and the pressure detector (52) is an electronic pressure gauge.

10. A demonstration experimental device for phase change of impurity-containing CO2 according to any one of claims 1 to 6, characterized in that: The top of the high-pressure reactor (1) is provided with a vent, and a manual vent valve (61) is installed at the vent.

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