Temperature control device for liquid carbon dioxide storage

Abstract

A temperature control device for liquid carbon dioxide storage comprises a temperature sensing device and a heat source control device. Wherein a conical shell with a narrow upper part and a wide lower part is arranged in the temperature sensing device, liquid carbon dioxide with the pressure equal to that of a storage tank is stored in the temperature sensing device, 24 bulges beneficial to heat transfer are designed to ensure that the internal temperature and the external temperature are close, a piston with good conductivity is arranged at the upper part, and connected conductors are controlled through different height positions of the piston; and the temperature adjusting device and the alarm device are further controlled. The device completely meets the temperature control standard of the storage and transportation link, ensures the safety and reliability of temperature regulation of the carbon dioxide storage tank, effectively solves the problem of temperature early warning control of liquid carbon dioxide in the storage and transportation process, and has the characteristics of convenience in operation, high durability, low cost and the like.

Description

Technical Field

[0001] The invention belongs to the field of instrument control and relates to a temperature control device based on phase change temperature control technology and used in a liquid carbon dioxide storage tank. Background Art

[0002] Phase change temperature control technology is a new type of thermal control technology developed from phase change energy storage technology. It has the advantages of reliable equipment performance, light weight and no energy consumption. It was first used in the aerospace field. With the development of materials science and emerging technologies, it has been gradually applied to military industry, civilian heat storage, cold chain logistics and electronic equipment heat dissipation. The current carbon dioxide storage tank storage technology and carbon dioxide liquefaction storage technology both use low-temperature and high-pressure liquid storage and transportation methods, which have extremely high requirements for temperature. However, traditional temperature control devices mainly rely on sensors such as thermistors and thermocouples to detect and adjust the temperature. It is difficult to adapt to the low-temperature and high-pressure carbon dioxide storage environment, and there are limitations in sensitivity and durability. Once the temperature in the tank rises, the liquid carbon dioxide will gasify and expand, and the pressure in the tank will rise rapidly, which is likely to cause leakage of the device, causing serious consequences such as environmental pollution and transportation accidents. The phase change temperature control technology used in the patent of this invention monitors the temperature through the volume change of the triple point of the substance, and uses the spring and the conductor connected to the piston as the trigger of the external heat source control device, thereby realizing sensitive temperature control, which can not only better avoid the above problems of traditional devices, but also reduce the cost of use and the difficulty of operation. In terms of material selection, a variety of low-temperature phase change materials that can be used in the field of temperature control have been discovered, but these phase change materials all have some disadvantages and it is difficult to achieve the desired effect. For example, inorganic materials have the advantages of a wide phase change temperature range, large latent heat per unit mass, and stable chemical properties, but their density is small and their thermal conductivity is poor; although hydrated salt materials have moderate density and large latent heat per unit mass, their chemical stability is poor and their supercooling is large. Summary of the invention

[0003] The present invention aims to solve the problems of high cost and short life caused by the existing temperature detection technology of liquid carbon dioxide storage tanks, which relies on easily damaged electronic components under low temperature and high pressure environment, and provides a temperature measurement device mainly composed of mechanical structure. The device can quickly respond to the temperature change of liquid carbon dioxide storage tanks, and has low cost and good safety.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: comprising a temperature detection device connected together and a temperature control and alarm device that receives a temperature detection signal and regulates the temperature inside a liquid carbon dioxide storage tank; the temperature detection device comprises a piston cylinder (105) with a sealed bottom and a carbon dioxide storage tank (107), a piston (104) is arranged in the piston cylinder, the piston (104) is connected to a spring (101) and moves with the change of the internal temperature of the liquid carbon dioxide storage tank, a conductor hole (103) with an embedded conductor (102) is arranged on the surface of the piston cylinder (105), and a bulge (106) for enhancing heat exchange and buffering the internal pressure change of the storage tank is arranged on the surface of the carbon dioxide storage tank (107), and the interior is filled with liquid carbon dioxide (108).

[0005] The piston (104) cylinder is composed of a cylindrical tube, and a conductor hole (103) is opened on the side thereof to communicate with an external temperature control device.

[0006] The conductor hole (103) has an electrically conductive conductor (102) embedded therein, and the conductor (102) is welded to the external heat source control device (2).

[0007] The upper end of the piston cylinder (105) is sealed and internally connected to a spring (101), the other end of the spring (101) is connected to a conductive piston (104), and the lower end of the piston cylinder (105) is connected to the narrow end of the carbon dioxide storage tank (107).

[0008] The piston (104) moves with the deformation of the spring (101), and when it moves to the conductor hole (103), it is connected to the circuit of the external temperature control device.

[0009] The carbon dioxide storage tank (107) is made of a conical tube, the wide end of which is sealed and the narrow end of which is connected to the piston cylinder (105).

[0010] The carbon dioxide storage tank (107) is provided with a bulge (106) on the outside thereof, which has the function of enhancing heat exchange and buffering the pressure change inside the storage tank.

[0011] The carbon dioxide storage tank (107) is filled with liquid carbon dioxide (108) and nitrogen, and the liquid carbon dioxide (108) and nitrogen are sealed in the carbon dioxide storage tank (107) by a piston.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention provides a piston cylinder (105) and a carbon dioxide storage tank (107) with a sealed bottom. A piston (104) is provided in the piston cylinder (105). The piston (104) is connected to a spring (101) and moves up and down as the temperature inside the liquid carbon dioxide storage tank changes. A conductor hole (103) with an embedded conductor (102) is provided on the surface of the piston cylinder (104). The conductor (102) is connected to an external heat source control device (2). When the preset temperature inside the liquid carbon dioxide storage tank rises and reaches the phase change point of carbon dioxide, the liquid in the carbon dioxide storage tank (107) is heated to a temperature of 104°C. The carbon dioxide (108) changes into gas, expands in volume, and pushes the piston (104) to move upward. When the piston (104) rises to the position where the conductor (102) is distributed on the piston cylinder (105), the conductor (102) at this position will connect the alarm device (202) and the temperature regulating device (201) connected in sequence, triggering an alarm and cooling the liquid carbon dioxide storage tank. When the temperature of the liquid carbon dioxide (108) is lower than the preset temperature, the gas is liquefied, the volume shrinks, the piston (104) moves downward, the circuit is disconnected, and the heat source control device (2) stops working. The temperature sensing device (1) is composed of a cylindrical tube and a conical tube that are interconnected, with a compact structure and sensitive volume change, which is easy to install and maintain. The design of the bulge (106) on the surface of the carbon dioxide storage tank effectively improves the heat exchange effect and reduces the influence of the pressure change inside the storage tank on the device. Therefore, the present invention can safely and reliably control the temperature in the liquid carbon dioxide storage tank, and has low use cost and convenient operation, meeting the requirements for controlling the temperature in the liquid carbon dioxide storage tank under storage and transportation conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the temperature control device of the present invention;

[0015] Among them, 101, spring; 102, conductor; 103, conductor hole; 104, piston, 105, piston cylinder, 106, bulge, 107, carbon dioxide storage tank, 108: liquid carbon dioxide, 201: temperature regulating device, 202: alarm device. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below with reference to the accompanying drawings.

[0017] Referring to the accompanying drawings, the present invention comprises two parts, namely a temperature detection device and a temperature control and execution device, wherein the temperature sensing device (1) is composed of a spring (101), a conductor (102), a conductor hole (103), a piston (104), a piston cylinder (105), a bulge (106), a carbon dioxide storage tank (107), liquid carbon dioxide (108) and the like; the heat source control device (2) comprises a temperature regulating device (201) and an alarm device (202).

[0018] The temperature sensing device (1) specifically includes a hollow insulating cylindrical piston cylinder (105), three circular conductor holes (103) on two symmetrical sides, and a good conductive conductor (102) is filled inside the conductor hole (103) while ensuring the movement of the piston (104); the bottom of the insulating cylindrical piston cylinder (105) is connected to a conical insulating carbon dioxide storage tank (107) with good thermal conductivity, the top of the insulating cylindrical piston cylinder (105) is closed, a spring (101) is fixed to the top, and a piston (103) is connected to the lower part of the spring (101), the piston (103) is a good conductive conductor, and is tightly connected to the inner wall of the insulating cylindrical piston cylinder (105). When the good conductive conductor (102) embedded in the insulating cylindrical piston cylinder (105) contacts the piston (104), the piston (104) can conduct current between two conductors (102) at the same height. At the same time, the piston (102) has good air tightness and can prevent gas exchange between the upper and lower sides. The three pairs of conductors (102) are distributed at a certain designed spacing. The spacing between the conductors (102) will be designed according to the specific use environment, and they are not connected to each other when there is no piston (103) in the middle. Each conductor (102) is externally connected to an actuator. A certain mass of liquid carbon dioxide (108) is installed inside the lower carbon dioxide storage tank (107), and a plurality of bulges (106) are arranged on the edge of the carbon dioxide storage tank (107) to increase the heat exchange area, improve the heat exchange efficiency, and help the carbon dioxide (108) inside the carbon dioxide storage tank (107) to exchange heat with the outside.

[0019] The specific positions of the three pairs of conductors (102) in the piston cylinder (105) are as follows: the bottom conductor (102) requires that when the device temperature reaches the warning temperature (a preset temperature value that is lower than a certain value of the critical temperature of carbon dioxide in the external environment), the piston just contacts this pair of conductors and conducts them; the middle conductor (102) requires that when the carbon dioxide reaches a dangerous temperature (a preset temperature value between the warning temperature and the critical temperature), the piston just contacts this pair of conductors and conducts them; the upper conductor (102) requires that when the device temperature reaches or is slightly higher than the critical temperature, the piston just contacts this pair of conductors and conducts them.

[0020] From bottom to top, three pairs of conductors (102) lead out a wire to connect different actuators. The bottom conductor (102) is only connected to an alarm device (202) for notifying the device that the temperature is close to a set dangerous value. In addition to the alarm device (202), the middle conductor (102) is also connected to a temperature adjustment device (2). When the temperature adjustment device (201) is turned on, it can control the temperature adjustment device (201) to adjust the temperature of the heat source. After the top conductor (102) is connected, the efficiency of the temperature adjustment device (201) can be improved, and further equipment can be added according to the use environment.

[0021] The piston (104) is relatively long, which can ensure that the lower part of the piston (104) will not separate from the lowermost conductor (102) during the upward movement.

[0022] The space above the piston (104) is close to vacuum, and its vacuum degree is maintained by a seal.

[0023] The method of use of the present invention is:

[0024] Taking the use environment of internal temperature detection and control of a large carbon dioxide storage tank as an example, when the external carbon dioxide temperature is lower than the warning temperature, the piston (104) is not connected to any set of conductors and the device has no feedback.

[0025] When the outside carbon dioxide temperature is higher than the warning temperature and lower than the dangerous temperature, the piston (104) is in equilibrium between the lower conductor (102) and the middle conductor (102). At this time, the first group of conductors (102) at the bottom is connected by the piston (104), and the middle and upper groups of conductors (102) are not connected. The actuator connected to the lower conductor (102), such as the heat source control device (2), is powered on and starts to operate, so as to control the temperature of the external carbon dioxide storage tank to be kept below the warning temperature.

[0026] When the outside carbon dioxide temperature is higher than the dangerous temperature and lower than the critical temperature, the piston (104) is between the middle and upper conductors (102), the middle conductor (102) is turned on, and the alarm device (201) connected to the bottom conductor is still running, while the temperature adjustment device (201) connected to the middle conductor starts to run.

[0027] When the external carbon dioxide temperature reaches the critical temperature or above, the equilibrium position of the piston (104) reaches above the uppermost conductor (102), all conductors (102) are turned on, and all actuators including the actuator connected to the uppermost conductor (102) are turned on, and safety measures such as pressure relief valves that cause large economic losses and are irreversible and personnel safety alarms begin to operate.

Claims

1. A temperature control device for a liquid carbon dioxide storage tank, characterized in that: The invention comprises a temperature sensing device (1) and a heat source control device (2); the temperature sensing device (1) comprises a spring (101), a conductor (102), a conductor hole (103), a piston (104), a piston cylinder (105), a bulge (106), a carbon dioxide storage tank (107) and liquid carbon dioxide (108); the carbon dioxide storage tank (107) contains liquid carbon dioxide (108); the outer surface of the carbon dioxide storage tank (107) is provided with a bulge (106); the carbon dioxide storage tank (107) is connected to the piston cylinder (105); the piston cylinder (105) is provided with a bulge (106); the carbon dioxide storage tank (107) is connected to the piston cylinder (105); the top of the piston cylinder (105) is provided with a bulge (106); the bulge (106) is provided on the outer surface of the carbon dioxide storage tank (107 ... The heat source control device (2) comprises a temperature regulating device (201) and an alarm device (202). The outside of the heat source control device (2) is connected to the conductor hole (103). The temperature sensing device (1) is connected to the heat source control device (2).

2. The temperature control device according to claim 1, characterized in that: The conical carbon dioxide storage tank (107) is sealedly connected to the cylindrical piston cylinder (105); the interior of the carbon dioxide storage tank (107) and the piston cylinder (105) are mutually connected; the wide end of the carbon dioxide storage tank (107) is sealed, and the narrow end of the carbon dioxide storage tank (107) is connected to the piston cylinder (105); and a conductor hole (103) connected to the external heat source control device (2) is opened on the side of the piston cylinder (105).

3. The temperature control device according to claim 1, characterized in that: The upper part of the spring (101) is fixed to the upper end of the piston cylinder (105), the lower part of the spring (101) is connected to the piston (104), the piston (104) is placed in the piston cylinder (105), and the piston (104) is in contact with the conductor (102).

4. The temperature control device according to claim 1, characterized in that: A conductor (102) is connected between the spring (101) and the piston (104). When the piston (104) moves to the conductor hole (103), the piston (104) contacts the conductor (102), and the conductor (102) is connected to the circuit of the external heat source control device (2).

5. The temperature control device according to claim 1, characterized in that: The carbon dioxide storage tank (107) is filled with liquid carbon dioxide (108), and the liquid carbon dioxide (108) is sealed in the carbon dioxide container (107) by the piston (104).

6. The temperature control device according to claim 1, characterized in that: A bulge (106) is provided on the surface of the carbon dioxide storage tank (107).

7. The temperature control device for a liquid carbon dioxide storage tank according to claim 1, characterized in that: A conductor (102) is welded inside the conductor hole (103), and the outside of the conductor (102) is connected to a temperature adjustment device (201) and an alarm device (202) via a circuit.

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