Liquid carbon dioxide storage tank exhaust venting control system, method and device

Abstract

The present application is applicable to the field of automatic control technology, and provides a gas exhaust and venting control system, method and device for liquid carbon dioxide storage tanks. By installing a sensor inside the liquid CO2 storage tank and determining the exhaust timing of the liquid CO2 storage tank based on the data collected by the sensor, automatic gas exhaust control of the liquid CO2 storage tank is achieved according to the actual operating conditions of the liquid CO2 storage tank. This not only ensures that the liquid CO2 storage tank is not damaged by overpressure, but also improves the overall gas exhaust efficiency of the liquid CO2 storage tank and reduces labor costs. In addition, by connecting an exhaust device equipped with a honeycomb pipe and a labyrinth pipe to the exhaust port of the liquid CO2 storage tank, the honeycomb pipe can shift the frequency of the airflow injection noise to a high frequency or ultra-high frequency that cannot be recognized by the human ear, and the labyrinth pipe can cause the gas CO2 flowing through to produce reverse turbulence, thereby effectively reducing the noise generated when the liquid CO2 storage tank is vented and vented.

Description

Technical Field

[0001] The present application belongs to the field of automatic control technology, and in particular relates to an exhaust and venting control system, method, and device for a liquid carbon dioxide storage tank. Background Art

[0002] In actual production activities, the temperature inside a liquid carbon dioxide (CO2) storage tank rises as the external temperature rises, and the liquid CO2 in the tank vaporizes, which increases the pressure inside the tank. If the pressure inside the tank exceeds the maximum pressure of the tank, it will cause damage to the tank due to overpressure. Therefore, it is necessary to vent the liquid CO2 storage tank regularly to release the gaseous CO2 into the air and reduce the risk of damage from overpressure.

[0003] However, liquid CO2 storage tanks generate a lot of noise when being vented, and workers are required to manually open the exhaust valve from time to time to vent the liquid CO2 storage tanks. This is not only cumbersome and labor-intensive, but also difficult to accurately grasp the appropriate timing of the venting operation, resulting in low overall efficiency of the venting operation. Summary of the Invention

[0004] In view of this, the embodiments of the present application provide a gas exhaust and venting control system, method and device for a liquid carbon dioxide storage tank to solve the technical problems of low overall efficiency, high labor cost and high noise in the existing gas exhaust and venting operations of liquid CO2 storage tanks.

[0005] In a first aspect, an embodiment of the present application provides an exhaust and venting control system for a liquid carbon dioxide storage tank, comprising: an exhaust and venting control device, an exhaust valve, a pressure sensor, a liquid level gauge, and an exhaust device;

[0006] The pressure sensor is used to collect the pressure value inside the liquid CO2 storage tank;

[0007] The liquid level meter is used to collect the liquid level value inside the liquid CO2 storage tank;

[0008] The exhaust valve is used to control the opening and closing of the exhaust port of the liquid CO2 storage tank;

[0009] The exhaust port is connected to the air inlet of the exhaust device, and the air inlet and air outlet of the exhaust device are connected through a low-noise exhaust duct; the low-noise exhaust duct includes a honeycomb duct and a labyrinth duct sequentially arranged between the air inlet and the air outlet; a plurality of evenly distributed small holes are opened on the pipe wall of the honeycomb duct; the labyrinth duct includes multiple stages of baffle sections;

[0010] The exhaust and venting control device is communicatively connected with the pressure sensor, the liquid level gauge and the exhaust valve, and is used to obtain the current pressure value and the current liquid level value inside the liquid CO2 storage tank; determine the safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value; determine the current exhaust pressure threshold of the liquid CO2 storage tank based on the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin; and control the exhaust valve to open when the current pressure value is equal to or greater than the current exhaust pressure threshold, so as to exhaust the liquid CO2 storage tank through the exhaust device.

[0011] In an optional implementation of the first aspect, the exhaust and venting control device is specifically used to: determine a correction coefficient of the pressure margin according to the current liquid level value; and determine the product of a preset basic pressure margin and the correction coefficient as the safety pressure margin.

[0012] In an optional implementation of the first aspect, the exhaust venting control device is further configured to determine a correction coefficient for the pressure margin according to the following formula:

[0013]

[0014] Wherein, k is the correction coefficient of the pressure margin, L dq is the current liquid level value, L zd is the minimum safe liquid level value of the liquid CO2 storage tank, L zg It is the maximum safe liquid level value of the liquid CO2 storage tank.

[0015] In an optional implementation of the first aspect, the exhaust venting control device is specifically configured to determine a difference between the maximum pressure value and the safety pressure margin as the current exhaust pressure threshold.

[0016] In an optional implementation of the first aspect, the exhaust venting control system further includes a temperature sensor; the temperature sensor is used to collect the temperature value inside the liquid CO2 storage tank;

[0017] The exhaust and venting control device is specifically further used to: obtain the exhaust temperature value and exhaust pressure value inside the liquid CO2 storage tank during the exhaust process; determine the saturated vapor pressure value of CO2 corresponding to the exhaust temperature value; and when the exhaust pressure value is equal to or less than the saturated vapor pressure value, control the exhaust valve to close to stop venting the liquid CO2 storage tank.

[0018] In an optional implementation of the first aspect, the length of the honeycomb pipe is determined by the following formula:

[0019]

[0020] Among them, L h is the length of the honeycomb pipe, K h is the preset length adjustment coefficient, D1 is the diameter of the honeycomb pipe, ΔP1 is the preset pressure drop of the honeycomb pipe, and P max is the maximum pressure value of the liquid CO2 storage tank.

[0021] In an optional implementation of the first aspect, the diameter of the small holes on the wall of the honeycomb pipe is determined by the following formula:

[0022]

[0023] Wherein, d is the diameter of the small hole on the wall of the honeycomb pipe, C d is the aperture correction factor;

[0024] The number of small holes on the wall of the honeycomb pipe is determined by the following formula:

[0025]

[0026] Wherein, N is the number of small holes on the wall of the honeycomb pipe, and ceil() is a rounding-up function.

[0027] In an optional implementation of the first aspect, the length of each baffle section included in the labyrinthine pipeline can be determined by the following formula:

[0028]

[0029] Among them, L m is the length of each baffle section, K m is the baffle efficiency coefficient of the labyrinthine pipeline, D2 is the diameter of the labyrinthine pipeline, ΔP2 is the preset pressure drop of the labyrinthine pipeline, P max is the maximum pressure-bearing value of the liquid CO2 storage tank, and ΔP1 is the preset pressure drop of the honeycomb pipeline.

[0030] In a second aspect, an embodiment of the present application provides a method for controlling exhaust and venting of a liquid carbon dioxide storage tank, comprising:

[0031] Get the current pressure and liquid level inside the liquid CO2 storage tank;

[0032] Determining a safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value;

[0033] Determining a current exhaust pressure threshold of the liquid CO2 storage tank according to the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin;

[0034] When the current pressure value is equal to or greater than the current exhaust pressure threshold, the exhaust valve is controlled to open, so as to exhaust the liquid CO 2 storage tank through the exhaust device.

[0035] In an optional implementation of the second aspect, determining the safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value includes:

[0036] determining a correction coefficient of the pressure margin according to the current liquid level value;

[0037] The product of a preset basic pressure margin and the correction coefficient is determined as the safety pressure margin.

[0038] In an optional implementation of the second aspect, determining a correction coefficient for the pressure margin according to the current liquid level value includes:

[0039] Determine the correction factor for the pressure margin according to the following formula:

[0040]

[0041] Wherein, k is the correction coefficient of the pressure margin, L dq is the current liquid level value, L zd is the minimum safe liquid level value of the liquid CO2 storage tank, L zg It is the maximum safe liquid level value of the liquid CO2 storage tank.

[0042] In an optional implementation of the second aspect, determining a current exhaust pressure threshold of the liquid CO2 storage tank according to the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin includes:

[0043] The difference between the maximum pressure value and the safety pressure margin is determined as the current exhaust pressure threshold.

[0044] In an optional implementation of the second aspect, the exhaust venting control method further includes:

[0045] Acquire the exhaust temperature and pressure inside the liquid CO2 storage tank during the exhaust process;

[0046] Determining the saturated vapor pressure value of CO2 corresponding to the exhaust temperature value;

[0047] When the exhaust pressure value is equal to or less than the saturated vapor pressure value, the exhaust valve is controlled to close to stop exhausting the liquid CO2 storage tank.

[0048] In a third aspect, an embodiment of the present application provides an exhaust and venting control device for a liquid CO2 storage tank, comprising a memory and a computer program stored in the memory and executable on a processor, wherein when the processor executes the computer program, the exhaust and venting control method for a liquid CO2 storage tank as described in any optional implementation of the second aspect above is implemented.

[0049] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the exhaust and venting control method of the liquid CO2 storage tank as described in any optional implementation method of the second aspect above.

[0050] The exhaust venting control system, method, device, and computer-readable storage medium for a liquid CO2 storage tank provided by the embodiments of the present application have the following beneficial effects:

[0051] The embodiment of the present application installs a sensor inside the liquid carbon dioxide storage tank and determines the exhaust timing and the exhaust stop timing of the liquid CO2 storage tank based on the data collected by the sensor, thereby realizing automatic exhaust control of the liquid CO2 storage tank according to the actual operating status of the liquid CO2 storage tank, which not only ensures that the liquid CO2 storage tank is not damaged by overpressure, but also improves the overall exhaust efficiency of the liquid CO2 storage tank and reduces labor costs. In addition, by providing an exhaust device including a honeycomb pipe and a labyrinth pipe, since the honeycomb pipe is provided with a plurality of evenly distributed small holes, each small hole will cause the air flow in the pipe to produce pressure loss and velocity attenuation. Therefore, when the gas CO2 discharged from the liquid CO2 storage tank flows through the honeycomb pipe, under the action of the multiple small holes on the pipe wall, the frequency of the air flow injection noise will shift to high frequency or ultra-high frequency that cannot be recognized by the human ear, thereby reducing the air flow injection noise; at the same time, the labyrinth pipe behind the honeycomb pipe can cause the gas CO2 flowing through to produce reverse turbulence, thereby reducing the flow rate of the gas CO2, further reducing the air flow injection noise generated when the liquid CO2 storage tank is exhausted and emptied. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0053] Figure 1 A schematic structural diagram of an exhaust and venting control system for a liquid CO2 storage tank provided in an embodiment of the present application;

[0054] Figure 2A schematic structural diagram of an exhaust device provided in an embodiment of the present application;

[0055] Figure 3 A schematic flow chart of a method for controlling exhaust and venting of a liquid CO2 storage tank provided in an embodiment of the present application;

[0056] Figure 4 A schematic diagram of the implementation flow of S302 in a method for controlling exhaust and venting of a liquid CO2 storage tank provided in an embodiment of the present application;

[0057] Figure 5 A schematic flow chart of a method for controlling exhaust and venting of a liquid CO2 storage tank provided in another embodiment of the present application;

[0058] Figure 6 A schematic structural diagram of an exhaust and venting control device provided in an embodiment of the present application;

[0059] Figure 7 A schematic structural diagram of an exhaust venting control device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0060] It should be noted that the terms used in the embodiments of the present application are only used to explain the specific embodiments of the present application and are not intended to limit the present application. In the description of the embodiments of the present application, unless otherwise specified, "multiple" refers to two or more than two, and "at least one" and "one or more" refer to one, two or more. The terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the definition of "first" and "second" features can explicitly or implicitly include one or more of the features.

[0061] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0062] In order to store or transport carbon dioxide (CO2) safely and stably, CO2 is usually stored in a liquid form in a dedicated storage tank (referred to as a liquid CO2 storage tank) to facilitate subsequent production activities. In actual production activities, when the outside temperature rises, the temperature inside the liquid CO2 storage tank will rise accordingly, and the liquid CO2 will vaporize, which will increase the pressure inside the tank. If the pressure inside the tank exceeds the maximum pressure of the tank, the tank will be damaged by overpressure. Therefore, it is necessary to vent the liquid CO2 storage tank from time to time to discharge the gas CO2 in the tank into the air, reduce the pressure inside the tank, and thus reduce the risk of damage to the tank by overpressure.

[0063] However, liquid CO2 storage tanks generate a lot of noise when they are being vented and emptied, and this noise is a type of fluid injection noise. Specifically, when the ratio of the pressure inside the liquid CO2 storage tank to the atmospheric pressure is equal to or greater than 1.89, the gas flow rate at the exhaust port will reach the speed of sound, which will generate a lot of airflow injection noise. This noise will not only affect the normal lives of residents near the work area, but also pose a potential hazard to the workers' hearing. In addition, the existing technology usually requires workers to manually open the exhaust valve from time to time to vent the liquid CO2 storage tank, which is not only cumbersome to operate and has high labor costs; it is also difficult for humans to accurately grasp the appropriate time for the venting and emptying operation, resulting in low overall efficiency of the venting and emptying operation.

[0064] In view of this, in order to reduce the labor cost required for the exhaust and venting operation of the liquid CO2 storage tank, improve the overall efficiency of the exhaust and venting operation, and reduce the noise generated by the exhaust and venting operation, the embodiment of the present application first provides a exhaust and venting control system for the liquid CO2 storage tank. Figure 1 , is a structural diagram of a gas exhaust control system for a liquid CO2 storage tank provided in an embodiment of the present application. Figure 1 As shown, the exhaust and venting control system may include: an exhaust and venting control device 11, an exhaust valve 12, a temperature sensor 13, a pressure sensor 14, a liquid level meter 15 and an exhaust device 16.

[0065] The exhaust valve 12 can be installed at the exhaust port 101 of the liquid CO2 storage tank 10 to control the opening and closing of the exhaust port 101. For example, upon receiving an opening signal from the exhaust and venting control device 11, the exhaust valve 12 can open the exhaust port 101 to exhaust the liquid CO2 storage tank 10, thereby discharging excess gas CO2 in the liquid CO2 storage tank 10 into the air. For another example, upon receiving a closing signal from the exhaust and venting control device 11, the exhaust valve 12 can close the exhaust port 101 to stop exhausting the liquid CO2 storage tank 10.

[0066] For example, the exhaust valve 12 may be an electromagnetic exhaust valve or a pneumatic angle seat exhaust valve with strong low temperature and high pressure resistance. The embodiment of the present application does not limit the specific type of the exhaust valve 12.

[0067] There can be at least two temperature sensors 13. One of the at least two temperature sensors 13 can be installed at the top of the liquid CO2 storage tank to collect the temperature of the gas space within the liquid CO2 storage tank. Another of the at least two temperature sensors 13 can be installed at the bottom of the liquid CO2 storage tank to collect the temperature of the liquid space within the liquid CO2 storage tank. The remaining temperature sensors 13 can be installed at any location within the liquid CO2 storage tank. Thus, when the liquid CO2 level within the liquid CO2 storage tank is higher than the installation height of the remaining temperature sensors 13, the remaining temperature sensors 13 can collect the temperature of the liquid space within the liquid CO2 storage tank. When the liquid CO2 level within the liquid CO2 storage tank is lower than the installation height of the remaining temperature sensors 13, the remaining temperature sensors 13 can collect the temperature of the gas space within the liquid CO2 storage tank. The term "gas space" refers to the space occupied by the gaseous CO2 within the liquid CO2 storage tank, and the term "liquid space" refers to the space occupied by the liquid CO2 within the liquid CO2 storage tank.

[0068] For example, the temperature sensor 13 may be a thermal resistor temperature sensor or a thermocouple temperature sensor with strong low temperature and high pressure resistance. The embodiment of the present application does not specifically limit the specific type of the temperature sensor 13.

[0069] The pressure sensor 14 can be installed at the top of the liquid CO2 storage tank to collect the pressure value inside the liquid CO2 storage tank. The pressure value inside the liquid CO2 storage tank can be used to represent the pressure of the gas CO2 in the liquid CO2 storage tank.

[0070] For example, the pressure sensor 14 may be a piezoresistive pressure sensor, a capacitive pressure sensor, or a diffused silicon pressure sensor with strong low temperature and high pressure resistance. The embodiment of the present application does not specifically limit the specific type of the pressure sensor 14.

[0071] The installation position of the liquid level gauge 15 can be determined according to the specific type of the liquid level gauge 15. For example, when the liquid level gauge 15 is an ultrasonic level gauge or a radar level gauge, the liquid level gauge 15 can be installed at the top position inside the liquid CO2 storage tank. When the liquid level gauge 15 is a static pressure level gauge, the liquid level gauge 15 can be installed at the bottom position inside the liquid CO2 storage tank. When the liquid level gauge 15 is a magnetic flap level gauge, the liquid level gauge 15 can be installed on the side wall inside the liquid CO2 storage tank. The embodiment of the present application does not specifically limit the specific type and installation position of the liquid level gauge 15.

[0072] Communication connections, such as wireless communication connections, are established between the exhaust and venting control device 11 and the exhaust valve 12 , the temperature sensor 13 , the pressure sensor 14 and the liquid level meter 15 .

[0073] The exhaust and venting control device 11 can be used to obtain corresponding sensor data from the temperature sensor 13, the pressure sensor 14 and the liquid level meter 15, determine the exhaust timing and the exhaust stop timing of the liquid CO2 storage tank 10 based on the obtained sensor data, and realize automatic exhaust control of the liquid CO2 storage tank 10 by controlling the opening and closing of the exhaust valve 12.

[0074] It should be noted that the specific process involved in the automatic exhaust control of the liquid CO2 storage tank 10 by the exhaust control device 11 can be referred to the description in the subsequent method embodiments and will not be described in detail here.

[0075] In some embodiments, the exhaust and venting control device 11 may specifically be an electronic device, such as a mobile phone, a tablet computer, or a laptop computer.

[0076] In other embodiments, the exhaust venting control device 11 may specifically be a control module, which may be, for example, a field-programmable gate array (FPGA), a programmable automation controller (PAC), or a programmable logic controller (PLC).

[0077] See also Figure 2 , is a schematic diagram of the structure of an exhaust device provided in an embodiment of the present application. Figure 2 (a) is a perspective view of the exhaust device 16. Figure 2 (b) is a top view of the exhaust device 16. Figure 2As shown in (a) of FIG. 1 , the exhaust device 16 may include a housing 160. For example, the housing 160 may be a cubic structure, such as a rectangular parallelepiped structure. The housing 160 may be provided with an air inlet 161 and an air outlet 162. The air inlet 161 and the air outlet 162 may be connected via a low-noise exhaust duct 163 disposed within the housing 160, and the air inlet 161 may be connected to the exhaust port 101 of the liquid CO2 storage tank 10 via a conventional exhaust duct.

[0078] like Figure 2 As shown in (b) of FIG. 1 , the low-noise exhaust duct 163 may include a honeycomb duct 1631 and a labyrinth duct 1632. The honeycomb duct 1631 and the labyrinth duct 1632 are sequentially connected between the air inlet 161 and the air outlet 162. That is, the air inlet of the honeycomb duct 1631 serves as the air inlet 161 of the low-noise exhaust duct 163, the air outlet of the honeycomb duct 1631 communicates with the air inlet of the labyrinth duct 1632, and the air outlet of the labyrinth duct 1632 serves as the air outlet 162 of the low-noise exhaust duct 163.

[0079] The honeycomb pipe 1631 refers to a pipe with a plurality of small holes opened on the pipe wall, and the plurality of small holes can be evenly distributed on the pipe wall of the honeycomb pipe 1631 .

[0080] The diameter of the honeycomb pipe 1631 may be the same as the diameter of the air inlet 161 of the exhaust device 16 , and the diameter of the air inlet 161 may be the same as the diameter of the exhaust port 101 of the liquid CO 2 storage tank 10 .

[0081] The length of the honeycomb pipe 1631, as well as the size and number of small holes in the pipe wall, can be determined based on the preset pressure drop of the honeycomb pipe 1631. The preset pressure drop of the honeycomb pipe 1631 describes the difference between the preset gas pressure at the inlet and outlet of the honeycomb pipe 1631. For example, the preset pressure drop of the honeycomb pipe 1631 can be 60% to 70% of the total pressure drop of the exhaust device 16. The total pressure drop of the exhaust device 16 refers to the difference between the gas pressure at the inlet 161 and the gas pressure at the outlet 162 of the exhaust device 16. For example, the total pressure drop of the exhaust device 16 can be the difference between the maximum pressure of the liquid CO2 storage tank 10 and the desired pressure at the outlet 162 of the exhaust device 16. In practical applications, to reduce noise during venting of the liquid CO2 storage tank 10, the desired pressure at the outlet 162 of the exhaust device 16 can be a preset multiple of the atmospheric pressure. This preset multiple can be greater than 1 and less than 1.3.

[0082] For example, the length of the honeycomb pipe 1631 can be determined according to the following formula (1):

[0083]

[0084] Among them, L h is the length of the honeycomb pipe 1631, D1 is the diameter of the honeycomb pipe 1631, ΔP1 is the preset pressure drop of the honeycomb pipe 1631, P max K is the maximum pressure value of the liquid CO2 storage tank 10. h is a preset length adjustment coefficient obtained based on fluid dynamics theory and experiments, which is related to the diameter of the pipeline, the flow rate and pressure of the gas in the pipeline, etc. For example, K h The value range can be 10 to 20.

[0085] The diameter of the small holes on the wall of the honeycomb pipe 1631 can be determined by the following formula (2):

[0086]

[0087] Wherein, d is the diameter of the small hole on the wall of the honeycomb pipe 1631. d is the aperture correction coefficient, which can be adjusted according to the actual noise reduction requirements. For example, C d The value range of can be 0.05~0.1.

[0088] The number of small holes on the wall of the honeycomb pipe 1631 can be determined by the following formula (3):

[0089]

[0090] Wherein, N is the number of small holes on the wall of the honeycomb pipe 1631, and ceil() is a rounding-up function.

[0091] Exemplarily, the diameter of the labyrinth-type pipe 1632 may be the same as the diameter of the honeycomb-type pipe 1631 .

[0092] The labyrinthine duct 1632 can be composed of multiple levels of baffles. The total number of baffles in the labyrinthine duct 1632 can be determined based on the preset pressure drop of the labyrinthine duct 1632 and the pressure drop that each baffle needs to bear. For example, the total number of baffles in the labyrinthine duct 1632 can be the ratio of the preset pressure drop of the labyrinthine duct 1632 to the pressure drop that each baffle needs to bear. The preset pressure drop of the labyrinthine duct 1632 can be the difference between the total pressure drop of the exhaust device 16 and the preset pressure drop of the honeycomb duct 1631.

[0093] The length of each baffle section can be determined by the following formula (4):

[0094]

[0095] Among them, L m is the length of each baffle section, K m is the baffle efficiency coefficient of the labyrinthine pipe 1632 , D2 is the diameter of the labyrinthine pipe 1632 , and ΔP2 is the preset pressure drop of the labyrinthine pipe 1632 .

[0096] In specific applications, K m The noise reduction efficiency of the baffle can be obtained through experiments and simulations. For example, K m The value range can be 2 to 3.

[0097] From the above, it can be seen that the embodiment of the present application realizes automatic exhaust control of the liquid CO2 storage tank according to the actual operating conditions of the liquid CO2 storage tank by installing a temperature sensor, a pressure sensor and a liquid level gauge inside the liquid CO2 storage tank, and determining the exhaust timing and the exhaust stop timing of the liquid CO2 storage tank based on the data collected by each sensor. This not only ensures that the liquid CO2 storage tank is not damaged by overpressure, but also improves the overall exhaust efficiency of the liquid CO2 storage tank and reduces labor costs. In addition, by setting up an exhaust device including a honeycomb pipe and a labyrinth pipe, since a plurality of evenly distributed small holes are opened on the honeycomb pipe, each small hole will cause pressure loss and velocity attenuation of the air flow in the pipe. Therefore, when the gas CO2 discharged from the liquid CO2 storage tank flows through the honeycomb pipe, under the action of the multiple small holes on the pipe wall, the frequency of the airflow injection noise will shift to high frequency or ultra-high frequency that cannot be recognized by the human ear, thereby reducing the airflow injection noise; at the same time, the labyrinth pipe behind the honeycomb pipe can cause the gas CO2 flowing through to produce reverse turbulence, thereby reducing the flow rate of the gas CO2 and further reducing the airflow injection noise; by reasonably setting the length of the honeycomb pipe, the number and diameter of the small holes on the pipe wall of the honeycomb pipe, the total number of bend sections included in the labyrinth pipe, and the length of each bend section, the upper limit value of the pressure of the gas CO2 finally discharged by the exhaust device can be close to atmospheric pressure, thereby effectively reducing the airflow injection noise generated when the liquid CO2 storage tank is exhausted and vented.

[0098] The embodiment of the present application also provides a method for controlling the exhaust and venting of a liquid CO2 storage tank. The execution subject of the exhaust and venting control method can be the exhaust and venting control device 11 mentioned above. For example, Figure 3 A schematic flow chart of a method for controlling the exhaust and venting of a liquid CO2 storage tank provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the exhaust venting control method may include S301 to S304, which are described in detail as follows:

[0099] S301, obtaining the current pressure value and current liquid level value inside the liquid CO2 storage tank.

[0100] The exhaust control device 11 can obtain the current pressure value inside the liquid CO2 storage tank from the pressure sensor 14 installed inside the liquid CO2 storage tank. For example, the exhaust control device 11 can obtain the current pressure value inside the liquid CO2 storage tank from the pressure sensor 14 once every first time period.

[0101] The exhaust control device 11 can obtain the current liquid level value inside the liquid CO2 storage tank from the liquid level meter 15 installed inside the liquid CO2 storage tank. For example, the exhaust control device 11 can obtain the current liquid level value inside the liquid CO2 storage tank from the liquid level meter 15 once every first time period.

[0102] Among them, the first duration can be set according to actual needs and is not particularly limited here.

[0103] S302, determining the safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value.

[0104] The safety pressure margin can be determined based on the current liquid level value and the preset basic pressure margin.

[0105] The basic pressure margin is a reserve between the maximum pressure of a liquid CO2 tank and its theoretically permitted maximum operating pressure to ensure that the tank is not damaged by overpressure during actual operation. In other words, the basic pressure margin represents the difference between the maximum pressure of a liquid CO2 tank and its theoretically permitted maximum operating pressure. The theoretically permitted maximum operating pressure of a liquid CO2 tank is lower than its maximum pressure.

[0106] Among them, the maximum pressure value of the liquid CO2 storage tank is used to indicate the maximum pressure that the liquid CO2 storage tank can withstand, which is related to the specifications of the liquid CO2 storage tank (for example, volume, material, etc.).

[0107] It should be noted that the base pressure margin is a pre-set fixed pressure value that does not change with the actual operating conditions within the liquid CO2 storage tank. In some embodiments, the base pressure margin can be determined based on the maximum pressure value of the liquid CO2 storage tank. For example, the base pressure margin can be 20% to 30% of the maximum pressure value. For example, assuming the maximum pressure value of the liquid CO2 storage tank is 4 megapascals (MPa), the base pressure margin can be 0.8 MPa or 1 MPa, etc.

[0108] It is understandable that in actual applications, the liquid level of the liquid CO2 in the liquid CO2 storage tank will affect the rate of change of the pressure of the gas CO2. Specifically, when the liquid level of the liquid CO2 is high, the gas space in the liquid CO2 storage tank is small, which makes the rate of change of the pressure of the gas CO2 relatively fast; when the liquid level of the liquid CO2 is low, the gas space in the liquid CO2 storage tank is large, which makes the rate of change of the pressure of the gas CO2 relatively slow. Therefore, in order to more accurately control the exhaust and venting operation of the liquid CO2 storage tank and ensure that the liquid CO2 storage tank is not damaged by overpressure, the basic pressure margin can be adjusted according to the current liquid level value of the liquid CO2 storage tank to obtain a safety pressure margin that matches the current liquid level value, so as to control the exhaust of the liquid CO2 storage tank according to the safety pressure margin.

[0109] Based on this, in a specific implementation, S302 may include the following: Figure 4 S3021 to S3022 shown are described in detail as follows:

[0110] S3021, determine the correction coefficient of the pressure margin according to the current liquid level value.

[0111] It is understandable that, since the pressure change rate of the gas CO2 in the liquid CO2 storage tank is faster when the current liquid level value is larger, more pressure margin can be reserved; when the current liquid level value is smaller, the pressure change rate of the gas CO2 in the liquid CO2 storage tank is slower, so less pressure margin can be reserved to ensure that the pressure value inside the liquid CO2 storage tank will never reach the maximum pressure value of the liquid CO2 storage tank, thereby reducing the risk of the liquid CO2 storage tank being damaged by overpressure.

[0112] For example, the exhaust venting control device 11 may determine the correction coefficient of the pressure margin by the following formula (5):

[0113]

[0114] Where k is the correction coefficient of pressure margin, L dq is the current liquid level value of the liquid CO2 storage tank, L zd is the minimum safe liquid level value of the liquid CO2 storage tank, L zg It is the highest safe liquid level value of the liquid CO2 storage tank.

[0115] It should be noted that the minimum safe liquid level value and the maximum safe liquid level value can be set according to actual needs. For example, the minimum safe liquid level value can be 10% of the height of the liquid CO2 storage tank, and the maximum safe liquid level value can be 85% of the height of the liquid CO2 storage tank.

[0116] According to the above formula (1), as the current liquid level value inside the liquid CO2 storage tank increases, the correction coefficient of the pressure margin will increase accordingly. Specifically, In the case of , the correction factor of pressure margin is equal to 1; In the case of , the correction coefficient of pressure margin is less than 1; In all cases, the correction coefficient of pressure margin is greater than 1.

[0117] S3022: Determine the product of the preset basic pressure margin and the correction coefficient as the safety pressure margin.

[0118] It is understandable that, as the current liquid level value inside the liquid CO2 storage tank increases, the correction coefficient of the pressure margin increases accordingly, and therefore the safety pressure margin also increases accordingly.

[0119] S303: Determine a current exhaust pressure threshold of the liquid CO2 storage tank according to the maximum pressure value and the safety pressure margin of the liquid CO2 storage tank.

[0120] In a specific implementation, the exhaust and venting control device 11 may determine the difference between the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin as the current exhaust pressure threshold of the liquid CO2 storage tank.

[0121] It is understandable that as the current liquid level inside the liquid CO2 storage tank increases, the safety pressure margin increases, and therefore the current exhaust pressure threshold of the liquid CO2 storage tank decreases accordingly. In other words, the higher the current liquid level inside the liquid CO2 storage tank, the lower the current exhaust pressure threshold of the liquid CO2 storage tank. This can prevent the pressure inside the liquid CO2 storage tank from reaching the maximum pressure value due to the rapid rate of pressure change of the gas CO2 in the liquid CO2 storage tank.

[0122] S304: When the current pressure value is equal to or greater than the current exhaust pressure threshold, the exhaust valve is controlled to open to exhaust the liquid CO2 storage tank through the exhaust device.

[0123] It can be understood that when the current pressure value inside the liquid CO2 storage tank is equal to or greater than the current exhaust pressure threshold inside the liquid CO2 storage tank, it means that the gas pressure of the gas CO2 in the liquid CO2 storage tank is about to approach the maximum pressure in the liquid CO2 storage tank. At this time, by venting the liquid CO2 storage tank, it can be ensured that the pressure value inside the liquid CO2 storage tank is always less than the maximum pressure value in the liquid CO2 storage tank, thereby reducing the risk of the liquid CO2 storage tank being damaged by overpressure.

[0124] It should be noted that the beneficial effects of the exhaust venting control method provided in the embodiment of the present application can be referred to the relevant description in the above system embodiment and will not be repeated here.

[0125] See also Figure 5 , is a schematic flow chart of a method for controlling exhaust and venting of a liquid CO2 storage tank provided in another embodiment of the present application, such as Figure 5 As shown, in this embodiment, the exhaust and venting control method may further include S305 to S307, which are described in detail as follows:

[0126] S305 , obtaining the exhaust temperature and pressure inside the liquid CO 2 storage tank during the exhaust process.

[0127] During the process of venting the liquid CO2 storage tank, in order to determine the timing to stop venting the liquid CO2 storage tank, the exhaust and venting control device 11 can obtain the exhaust temperature value inside the liquid CO2 storage tank during the exhaust process from the temperature sensor 13 installed inside the liquid CO2 storage tank. Exemplarily, the exhaust and venting control device 11 can determine the average of multiple temperature values ​​obtained from multiple temperature sensors 13 during the exhaust process as the exhaust temperature value inside the liquid CO2 storage tank during the exhaust process. Exemplarily, during the exhaust process, the exhaust and venting control device 11 can obtain the exhaust temperature value inside the liquid CO2 storage tank during the exhaust process every second time period.

[0128] The exhaust and venting control device 11 can obtain the exhaust pressure value inside the liquid CO2 storage tank during the exhaust process from the pressure sensor 14 installed inside the liquid CO2 storage tank. For example, during the exhaust process, the exhaust and venting control device 11 can obtain the exhaust pressure value inside the liquid CO2 storage tank during the exhaust process from the pressure sensor 14 every second time period.

[0129] Among them, the second duration can be set according to actual needs and is not specifically limited here.

[0130] It is understandable that as the gas CO2 in the liquid CO2 storage tank gradually decreases during the exhaust process, the exhaust pressure value inside the liquid CO2 storage tank will also gradually decrease.

[0131] S306: Determine the saturated vapor pressure value of CO2 corresponding to the exhaust gas temperature value.

[0132] The saturated vapor pressure value of CO2 corresponding to the exhaust temperature value is used to describe the pressure value of gaseous CO2 when liquid CO2 and gaseous CO2 reach a dynamic equilibrium state at the corresponding exhaust temperature, that is, the maximum vapor pressure value that liquid CO2 can generate at the corresponding exhaust temperature.

[0133] It should be noted that the saturated vapor pressure of CO2 is different at different exhaust temperatures.

[0134] Exemplarily, the exhaust gas discharge control device 11 may determine the saturated vapor pressure value of CO2 corresponding to the exhaust gas temperature value by looking up a table. For example, the exhaust gas discharge control device 11 may determine the saturated vapor pressure value of CO2 corresponding to the exhaust gas temperature value by looking up a table of correspondence between temperature values ​​and saturated vapor pressure values ​​of CO2.

[0135] S307: When the exhaust pressure value is equal to or less than the saturated vapor pressure value, the exhaust valve is controlled to close to stop exhausting the liquid CO2 storage tank.

[0136] It is understood that at the saturated vapor pressure of CO2 corresponding to the exhaust temperature, the liquid CO2 and gaseous CO2 in the liquid CO2 storage tank are in equilibrium. When the exhaust pressure value inside the liquid CO2 storage tank drops below the saturated vapor pressure value, the evaporation rate of the liquid CO2 inside the liquid CO2 storage tank will increase. Therefore, in order to reduce the loss of liquid CO2 caused by the rapid evaporation of liquid CO2, the exhaust and venting control device 11 can control the exhaust valve to close when the exhaust pressure value during the exhaust process is equal to or less than the saturated vapor pressure value, thereby stopping the exhaust of the liquid CO2 storage tank.

[0137] It can be seen from the above that the exhaust and venting control method provided in this embodiment can not only realize the automatic exhaust control of the liquid CO2 storage tank, but also reduce the loss of liquid CO2 caused by the rapid evaporation of liquid CO2.

[0138] It can be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0139] Based on the exhaust and venting control method of the liquid CO2 storage tank provided in the above embodiment, the present application further provides an embodiment of the exhaust and venting control device for implementing the above method embodiment. Figure 6 , is a schematic diagram of the structure of an exhaust venting control device provided in an embodiment of the present application. For ease of explanation, only the parts related to this embodiment are shown. Figure 6 As shown, the exhaust venting control device may include: an acquisition unit 61 , a first determination unit 62 , a second determination unit 63 and an exhaust valve control unit 64 .

[0140] The acquisition unit 61 is used to acquire the current pressure value and the current liquid level value inside the liquid CO2 storage tank.

[0141] The first determining unit 62 is configured to determine a safety pressure margin of the liquid CO 2 storage tank corresponding to the current liquid level value.

[0142] The second determining unit 63 is configured to determine a current exhaust pressure threshold of the liquid CO 2 storage tank according to the maximum pressure-bearing value of the liquid CO 2 storage tank and the safety pressure margin.

[0143] The exhaust valve control unit 64 is configured to control the exhaust valve to open when the current pressure value is equal to or greater than the current exhaust pressure threshold, so as to exhaust the liquid CO 2 storage tank through the exhaust device.

[0144] Optionally, the first determining unit 62 includes a correction coefficient determining unit and a pressure margin determining unit.

[0145] The correction coefficient determination unit is used to determine the correction coefficient of the pressure margin according to the current liquid level value.

[0146] The pressure margin determining unit is configured to determine a product of a preset basic pressure margin and the correction coefficient as the safety pressure margin.

[0147] Optionally, the correction coefficient determination unit is specifically configured to determine the correction coefficient of the pressure margin according to the following formula:

[0148]

[0149] Wherein, k is the correction coefficient of the pressure margin, L dq is the current liquid level value, L zd is the minimum safe liquid level value of the liquid CO2 storage tank, L zg It is the maximum safe liquid level value of the liquid CO2 storage tank.

[0150] Optionally, the second determining unit 63 is specifically configured to determine a difference between the maximum pressure value and the safety pressure margin as the current exhaust pressure threshold.

[0151] Optionally, the exhaust gas discharge control device 11 may further include a third determination unit.

[0152] The acquisition unit 11 is further configured to acquire the exhaust temperature and pressure inside the liquid CO2 storage tank during the exhaust process.

[0153] The third determining unit is used to determine the saturated vapor pressure value of CO2 corresponding to the exhaust temperature value.

[0154] The exhaust valve control unit 64 is further configured to control the exhaust valve to close when the exhaust pressure value is equal to or less than the saturated vapor pressure value, so as to stop exhausting the liquid CO 2 storage tank.

[0155] It should be noted that the information interaction, execution process and other contents between the above-mentioned units are based on the same concept as the method embodiment of this application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0156] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units as needed, that is, the internal structure of the control device can be divided into different functional units to complete all or part of the functions described above. The functional units in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of each unit in the above-mentioned control device can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0157] See also Figure 7 , Figure 7 This is a schematic diagram of the structure of an exhaust and venting control device provided in another embodiment of the present application. Figure 7 As shown, the exhaust and venting control device 11 provided in this embodiment may include: a processor 110, a memory 111, and a computer program 112 stored in the memory 111 and executable on the processor 110, such as a program corresponding to the exhaust and venting control method for a liquid CO2 storage tank. When the processor 110 executes the computer program 112, each step in the above-mentioned exhaust and venting control method for a liquid CO2 storage tank is implemented, such as Figure 3 Alternatively, when the processor 110 executes the computer program 112, the functions of each module / unit in the above-mentioned exhaust and venting control device embodiment are realized, for example Figure 6 The functions of the units 61 to 64 are shown.

[0158] For example, the computer program 112 can be divided into one or more modules / units, one or more modules / units are stored in the memory 111 and executed by the processor 110 to complete the present application. One or more modules / units can be a series of computer program instruction segments that can complete specific functions. The instruction segments are used to describe the execution process of the computer program 112 in the exhaust and venting control device 11. For example, the computer program 112 can be divided into an acquisition unit, a first determination unit, a second determination unit, and an exhaust valve control unit. The specific functions of each unit can be found in Figure 7The relevant descriptions in the corresponding embodiments are not repeated here.

[0159] Those skilled in the art will understand that Figure 7 The exhaust and venting control device 11 is merely an example and does not limit the exhaust and venting control device 11 , and may include more or fewer components than shown in the figure, or a combination of certain components, or different components.

[0160] The processor 110 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0161] The memory 111 may be an internal storage unit of the exhaust and venting control device 11, such as a hard disk or memory of the exhaust and venting control device 11. The memory 111 may also be an external storage device of the exhaust and venting control device 11, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, or a flash card equipped on the exhaust and venting control device 11. Furthermore, the memory 111 may also include both an internal storage unit and an external storage device of the exhaust and venting control device 11. The memory 111 is used to store computer programs and other programs and data required by the method. The memory 111 may also be used to temporarily store data that has been output or is to be output.

[0162] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, each step in the exhaust venting control system described in the above method embodiment is implemented.

[0163] An embodiment of the present application provides a computer program product. When the computer program product is run on a control device, the control device implements the steps in the above-mentioned various method embodiments.

[0164] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0165] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0166] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A gas exhaust and venting control system for a liquid carbon dioxide storage tank, characterized in that: include: Exhaust and venting control device, exhaust valve, pressure sensor, liquid level gauge and exhaust device; The pressure sensor is used to collect the pressure value inside the liquid CO2 storage tank; The liquid level meter is used to collect the liquid level value inside the liquid CO2 storage tank; The exhaust valve is used to control the opening and closing of the exhaust port of the liquid CO2 storage tank; The exhaust port is connected to the air inlet of the exhaust device, and the air inlet and air outlet of the exhaust device are connected through a low-noise exhaust duct; the low-noise exhaust duct includes a honeycomb duct and a labyrinth duct sequentially arranged between the air inlet and the air outlet; a plurality of evenly distributed small holes are opened on the pipe wall of the honeycomb duct; the labyrinth duct includes multiple stages of baffle sections; The exhaust and venting control device is in communication with the pressure sensor, the liquid level gauge, and the exhaust valve, and is used to obtain the current pressure value and the current liquid level value inside the liquid CO2 storage tank; determining a safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value; determining a current exhaust pressure threshold of the liquid CO2 storage tank based on the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin; and controlling the exhaust valve to open when the current pressure value is equal to or greater than the current exhaust pressure threshold, so as to exhaust the liquid CO2 storage tank through the exhaust device; The exhaust and venting control device is specifically used to: determine a correction coefficient of the pressure margin according to the current liquid level value; and determine the product of a preset basic pressure margin and the correction coefficient as the safety pressure margin; The exhaust and venting control device is further configured to determine a correction coefficient of the pressure margin according to the following formula: ； in, k is the correction coefficient of the pressure margin, L dq is the current liquid level value, L zd is the minimum safe liquid level value of the liquid CO2 storage tank, L zg is the maximum safe liquid level value of the liquid CO2 storage tank; The exhaust and venting control device is specifically configured to: determine the difference between the maximum pressure value and the safety pressure margin as the current exhaust pressure threshold; The exhaust venting control system further includes a temperature sensor; The temperature sensor is used to collect the temperature value inside the liquid CO2 storage tank; The exhaust and venting control device is specifically further used to: obtain the exhaust temperature value and exhaust pressure value inside the liquid CO2 storage tank during the exhaust process; determine the saturated vapor pressure value of CO2 corresponding to the exhaust temperature value; and when the exhaust pressure value is equal to or less than the saturated vapor pressure value, control the exhaust valve to close to stop venting the liquid CO2 storage tank.

2. The exhaust venting control system according to claim 1, characterized in that: The length of the honeycomb pipe is determined by the following formula: ； in, L h is the length of the honeycomb pipe, K h is the preset length adjustment coefficient, D 1 is the diameter of the honeycomb pipe, Δ P 1 is the preset pressure drop of the honeycomb pipeline, P max is the maximum pressure value of the liquid CO2 storage tank.

3. The exhaust venting control system according to claim 2, characterized in that: The diameter of the small holes on the wall of the honeycomb pipe is determined by the following formula: ； in, d is the diameter of the small holes on the wall of the honeycomb pipe, C d is the aperture correction factor; The number of small holes on the wall of the honeycomb pipe is determined by the following formula: ； in, N is the number of small holes on the wall of the honeycomb pipe, ceil () is the rounding up function.

4. The exhaust venting control system according to claim 1, characterized in that: The length of each baffle section included in the labyrinthine pipeline is determined by the following formula: ； in, L m is the length of each baffle section, K m is the baffle efficiency coefficient of the labyrinthine pipeline, D 2 is the diameter of the labyrinthine pipe, Δ P 2 is the preset pressure drop of the labyrinth pipeline, P max is the maximum pressure of the liquid CO2 storage tank, Δ P 1 is the preset pressure drop of the honeycomb pipeline.

5. A method for controlling the exhaust and venting of a liquid carbon dioxide storage tank, characterized in that: An exhaust and venting control device used in an exhaust and venting control system according to any one of claims 1 to 4; The exhaust and venting control method includes: Get the current pressure and liquid level inside the liquid CO2 storage tank; Determining a safety pressure margin of the liquid CO2 storage tank corresponding to the current liquid level value; Determining a current exhaust pressure threshold of the liquid CO2 storage tank according to the maximum pressure value of the liquid CO2 storage tank and the safety pressure margin; When the current pressure value is equal to or greater than the current exhaust pressure threshold, the exhaust valve is controlled to open, so as to exhaust the liquid CO 2 storage tank through the exhaust device.

6. A gas exhaust control device for a liquid carbon dioxide storage tank, characterized in that: The method comprises a memory and a computer program stored in the memory and operable on a processor, wherein the processor implements the exhaust venting control method according to claim 5 when executing the computer program.

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