Cryogenic medium loading pretreatment device

Abstract

This utility model relates to a cryogenic medium loading pretreatment device, comprising a cryogenic medium delivery pipeline from a cryogenic medium tank area and an economizer. The cryogenic medium delivery pipeline includes a first branch and a second branch. The first branch is connected to the shell-side inlet of the economizer, and the second branch is connected to the tube-side inlet of the economizer. The tube-side outlet of the economizer is also connected to a cryogenic medium output pipeline for loading. The shell-side outlet of the economizer is connected to a gaseous medium output pipeline for vaporized gaseous medium to flow out. A first control valve is provided on the first branch. This first control valve is electrically connected to the level transmitter of the economizer and a first temperature sensor on the cryogenic medium output pipeline to form a linkage control. The advantage is that it effectively solves the problem of high temperature of the cryogenic medium when transported to the loading and unloading area via long-distance pipeline, thereby reducing economic losses and safety hazards.

Description

Technical Field

[0001] This utility model relates to the field of cryogenic medium loading technology, and in particular to a cryogenic medium loading pretreatment device. Background Technology

[0002] Loading cryogenic media (such as ethylene, ethane, LNG, etc.) requires strict temperature control, necessitating a relatively low temperature range. Most newly built plants have loading and unloading facilities in their cryogenic tank areas to meet temperature and pressure requirements. However, some expansion and renovation projects, to meet spacing requirements and maximize site utilization, have tank areas far from loading and unloading areas, sometimes even spanning the entire plant or industrial park. This inevitably leads to significant temperature loss during long-distance pipeline transport of cryogenic media. When the media arrives at the loading area, the loading temperature is too high, and the high temperature after loading makes it prone to reheating, increasing the vapor pressure during transport and further increasing the pressure in the tank trucks, posing a significant safety hazard. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a cryogenic medium loading pretreatment device that can effectively solve the problem of high temperature of cryogenic medium when it is transported to the loading and unloading area of ​​long-distance pipelines, thereby reducing economic losses and safety hazards, in light of the current state of the technology.

[0004] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: a cryogenic medium loading pretreatment device, including a cryogenic medium conveying pipeline from the cryogenic medium tank area and an economizer. The cryogenic medium conveying pipeline includes a first branch and a second branch. The first branch is connected to the shell-side inlet of the economizer, and the second branch is connected to the tube-side inlet of the economizer. The tube-side outlet of the economizer is also connected to a cryogenic medium output pipeline for loading. The shell-side outlet of the economizer is connected to a gas phase medium output pipeline for vaporized gas phase medium to flow out. A first control valve is provided on the first branch. The first control valve is electrically connected to the liquid level transmitter of the economizer and the first temperature sensor conveyed on the cryogenic medium output pipeline to form a linkage control.

[0005] To recover the bubble point gas and considering that uncontrolled gas phase output might lead to unstable shell-side pressure in the economizer, affecting heat exchange efficiency and safety, the gas phase output line is equipped with a second control valve and a bubble point gas compressor located downstream of this second control valve. By using the second control valve and the bubble point gas compressor, the shell-side outlet pressure is precisely controlled (e.g., maintained at a low pressure of 10 kPa), ensuring sufficient vaporization and stable pressure of the shell-side medium, thereby improving heat exchange efficiency and system safety.

[0006] As an improvement, the second branch and the cryogenic medium output pipeline are respectively equipped with a second control valve and a third control valve at the tube-side inlet and tube-side outlet adjacent to the economizer. By setting the second control valve (tube-side inlet) and the third control valve (tube-side outlet), the tube-side medium flow rate is precisely adjusted, the heat exchange process is optimized, and the outlet cryogenic medium temperature is ensured to meet the loading requirements.

[0007] As an improvement, a second pressure transmitter is also provided on the first branch, downstream of the first control valve. By using the second pressure transmitter, the pressure of the medium in the first branch can be monitored in real time, providing more comprehensive parameter data for the adjustment of the first control valve and improving the accuracy of shell-side level and tube-side pressure control.

[0008] As an improvement, the economizer is also equipped with a vent line, which is connected to the downstream flare system. This connection between the vent line and the flare system allows for the safe release of gas in abnormal situations, preventing overpressure accidents and improving system safety.

[0009] Compared with existing technologies, the advantages of this utility model are as follows: The cryogenic medium pretreatment device for loading vehicles, by setting up an economizer, divides the cryogenic medium from the tank area into two paths. One path enters the shell side for vaporization and heat absorption, while the other path enters the tube side for cooling. Utilizing the latent heat of vaporization of the medium itself, active pre-cooling of the liquid medium during loading is achieved, significantly reducing its temperature. This process requires no external cold source, making it energy-efficient and highly effective. Through the linkage control of the first control valve with liquid level and temperature signals, the economizer liquid level and outlet temperature can be automatically stabilized, ensuring that the loaded medium is always in a qualified cryogenic state. This significantly reduces vaporization losses and tank truck pressure increases caused by reheating during transportation, avoiding wasteful emissions and improving safety levels, thus combining economy and safety. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the low-temperature medium loading pretreatment device according to an embodiment of the present invention. Detailed Implementation

[0011] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0012] In the specification and claims of this utility model, terms indicating direction, such as "front," "rear," "upper," "lower," "left," "right," "side," "top," and "bottom," are used to describe various exemplary structural parts and elements of this utility model. However, the use of these terms is merely for the purpose of explanation and is based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this utility model can be arranged in different orientations, these terms indicating direction are for illustrative purposes only and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

[0013] Figure 1 A preferred embodiment of the cryogenic medium loading pretreatment device of this utility model is shown. The cryogenic medium loading pretreatment device is used to solve the problem of excessively high temperatures of cryogenic media during long-distance pipeline transportation to the loading and unloading area. The device includes a cryogenic medium transportation pipeline leading from the cryogenic medium tank area, an economizer 10, and related control components.

[0014] The cryogenic medium delivery pipeline is divided into a first branch 11 and a second branch 12. The first branch 11 is connected to the shell-side inlet of the economizer 10, and the second branch 12 is connected to the tube-side inlet of the economizer 10. The tube-side outlet of the economizer 10 is connected to a cryogenic medium output pipeline 13 for loading and delivering the cooled cryogenic medium to the tank truck. The shell-side outlet of the economizer 10 is connected to a gas phase medium output pipeline 14 for discharging the vaporized gas phase medium.

[0015] In the shell side of the economizer 10, the cryogenic medium enters through the first branch 11, absorbs heat from the medium in the tube side, and vaporizes, thus generating a cooling effect. The medium in the tube side comes from the second branch 12, and after being cooled by the shell side medium, it is output through the cryogenic medium output line 13, resulting in a significant temperature reduction that meets the vehicle loading requirements.

[0016] To ensure the stable operation of the economizer 10, a first control valve 111 is installed on the first branch 11. This first control valve 111 is electrically connected to a level transmitter 101 installed on the economizer 10 and a first temperature sensor 131 installed on the cryogenic medium output pipeline 13, forming a linkage control system. The level transmitter 101 monitors the liquid level in the shell side of the economizer 10 in real time, and the first temperature sensor 131 monitors the temperature of the output cryogenic medium in real time. Based on the liquid level and temperature signals, the first control valve 111 automatically adjusts the flow rate of the first branch 11 to maintain the shell side liquid level within the set range and ensure that the output temperature meets the requirements. For example, when the liquid level is too low or the output temperature is too high, the first control valve 111 opens wider to increase the shell side feed and enhance the vaporization cooling effect; conversely, it closes the valve when the liquid level is too low.

[0017] A second control valve 141 and a bubble point gas compressor are installed on the gas phase medium output line 14. The second control valve 141 is used to regulate the outlet pressure of the gas phase medium, maintain a stable shell-side pressure (e.g., around 10 kPa), and avoid pressure fluctuations affecting heat exchange efficiency and safety. The bubble point gas compressor compresses the gas phase medium and recovers it to the tank area or treatment system, reducing gas emissions and economic losses.

[0018] A second control valve 141 is installed on the second branch line 12 at the tube-side inlet adjacent to the economizer 10, and a third control valve 132 is installed on the cryogenic medium output line 13 at the tube-side outlet adjacent to the economizer 10. These valves are used to finely regulate the flow rate and pressure of the tube-side medium, optimize the heat exchange process, and ensure precise control of the output temperature.

[0019] The economizer 10 is equipped with a first pressure transmitter 102 for detecting the shell-side working pressure, and a second pressure transmitter 112 is also provided on the first branch 11 downstream of the first control valve 111 for monitoring the temperature of the medium entering the shell side. This provides additional parameters for the control of the first control valve 111 and improves the control accuracy.

[0020] The top of the economizer 10 is also equipped with a vent line 15, which is connected to the downstream flare system. In abnormal circumstances, such as excessive pressure or equipment failure, the vent line 15 will automatically open to safely release the gas to the flare system and prevent overpressure accidents.

[0021] In this embodiment, the economizer 10 employs a shell-and-tube heat exchanger, with both the shell and tube sides designed to be made of low-temperature resistant materials, such as stainless steel, to withstand corrosion and thermal stress from the low-temperature medium. All control valves are electrically or pneumatically operated and connected to a PLC or DCS control system for automated operation.

[0022] The cryogenic medium pretreatment device in this embodiment uses an economizer 10 to divide the cryogenic medium from the tank farm into two paths: one path enters the shell side for vaporization and heat absorption, while the other path enters the tube side for cooling. Utilizing the latent heat of vaporization of the medium itself, the device actively pre-cools the liquid medium being loaded, significantly reducing its temperature. This process requires no external cooling source, making it energy-efficient and highly effective. Through the linkage control of the first control valve 111 with the liquid level and temperature signals, the liquid level and outlet temperature of the economizer 10 can be automatically stabilized, ensuring that the loaded medium is always in a qualified cryogenic state. This significantly reduces vaporization losses and tank truck pressure increases caused by reheating during transportation, avoiding wasteful emissions and improving safety levels, thus combining economy and safety.

Claims

1. A cryogenic medium loading pretreatment device, characterized in that: The system includes a cryogenic medium delivery pipeline from the cryogenic medium tank area and an economizer (10). The cryogenic medium delivery pipeline includes a first branch (11) and a second branch (12). The first branch (11) is connected to the shell-side inlet of the economizer (10), and the second branch (12) is connected to the tube-side inlet of the economizer (10). The tube-side outlet of the economizer (10) is also connected to a cryogenic medium output pipeline (13) for loading. The shell-side outlet of the economizer (10) is connected to a gas phase medium output pipeline (14) for vaporized gas phase medium to flow out. A first control valve (111) is provided on the first branch (11). The first control valve (111) is electrically connected to the level transmitter (101) of the economizer (10) and the first temperature sensor (131) delivered on the cryogenic medium output pipeline (13) to form a linkage control.

2. The cryogenic medium loading pretreatment device according to claim 1, characterized in that: The gas phase medium output line (14) is equipped with a second control valve (141) and a bubble point gas compressor located downstream of the second control valve (141).

3. The cryogenic medium loading pretreatment device according to claim 1, characterized in that: The second branch (12) and the cryogenic medium output pipeline (13) are respectively provided with a second control valve (141) and a third control valve (132) at the pipe inlet and pipe outlet adjacent to the economizer (10).

4. The cryogenic medium loading pretreatment device according to claim 1, characterized in that: A second pressure transmitter (112) is also provided on the first branch (11) corresponding to the downstream of the first control valve (111).

5. The cryogenic medium loading pretreatment device according to any one of claims 1 to 4, characterized in that: The economizer (10) is also equipped with a vent line (15), which is connected to the downstream flare system.

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