Large LNG (Liquefied Natural Gas) low-temperature storage tank dome pouring pressure-maintaining safety relief device

Abstract

The utility model discloses a large LNG (liquefied natural gas) low-temperature storage tank dome pouring pressure-maintaining safety relief device which comprises an air blower, a pressure switch, a pressure relief water tank, a differential pressure gauge, a first pressure relief valve and a second pressure relief valve which are arranged outside a low-temperature storage tank, the front end of the differential pressure gauge extends into the low-temperature storage tank, and the air blower is communicated with the low-temperature storage tank through a first pipeline. The pressure relief water tank is communicated with the low-temperature storage tank through a second pipeline, a pressure switch and a first pressure relief valve are arranged on the second pipeline, and the first pressure relief valve and the second pressure relief valve are arranged in parallel. According to the utility model, not only is the risk of human intervention reduced, but also the reliability and the stability of operation are improved; meanwhile, the device also has a manual pressure relief function of a traditional device when the pressure is suddenly increased; and meanwhile, customization can be carried out according to different storage tank specifications, dwell pressures and process requirements, and the device is suitable for construction of various types of LNG concrete low-temperature storage tanks and has wide application prospects.

Description

Technical Field

[0001] The utility model belongs to the field of cryogenic storage tank processing, and in particular relates to a large-scale LNG cryogenic storage tank dome pouring pressure-maintaining safety relief device. Background Art

[0002] Natural gas has become a vital energy resource, and China's LNG imports are expected to increase annually. The construction of large-scale domestic LNG cryogenic storage tanks has also begun to develop rapidly. The pouring of the tank dome is a crucial step in the construction process, and maintaining pressure within the tank is essential for the dome concrete pouring process. Unstable pressure maintenance and uneven or rapid pressure release can lead to concrete cracking and dome stress deformation, increasing the cost of subsequent repairs. Failure to control cracks effectively can result in significant losses. Utility Model Content

[0003] In order to solve the above problems, the utility model discloses a large-scale LNG low-temperature storage tank dome casting pressure-maintaining safety relief device. It innovates on the existing basis and can effectively avoid accidents caused by excessive pressure, providing important safety guarantees for the dome casting process.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the present utility model is as follows:

[0005] A large-scale LNG cryogenic storage tank dome pouring pressure-maintaining safety relief device includes a blower, a pressure switch, a pressure relief water tank, a differential pressure gauge, a first pressure relief valve, and a second pressure relief valve, which are arranged outside the cryogenic storage tank. The front end of the differential pressure gauge extends into the cryogenic storage tank. The blower is connected to the cryogenic storage tank through a first pipe. The pressure relief water tank is connected to the cryogenic storage tank through a second pipe. A pressure switch and a first pressure relief valve are provided on the second pipe. The first pressure relief valve and the second pressure relief valve are arranged in parallel.

[0006] As a supplement to the present invention, there are two differential pressure gauges, which are respectively arranged at the bottom gate opening of the low-temperature storage tank and the perlite nozzle of the dome.

[0007] As a supplement to the present invention, the differential pressure gauge is a U-shaped differential pressure gauge.

[0008] As a supplement to the present invention, the number of the blowers is two.

[0009] As a supplement to the present invention, a control valve is provided on the pipeline.

[0010] The beneficial effects of the utility model are:

[0011] The utility model describes a large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device. The pressure-maintaining safety relief device design that combines traditional and new methods not only reduces the risk of human intervention, but also improves the reliability and stability of operation. At the same time, it also has the manual pressure relief function of traditional devices when the pressure increases sharply. At the same time, it can be customized according to different storage tank specifications, pressure maintenance pressures and process requirements, and is suitable for various types of LNG concrete cryogenic storage tank construction, with broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural diagram of the present utility model.

[0013] Figure 2 This is a schematic diagram of the differential pressure gauge described in the present utility model.

[0014] Figure 3 This is a schematic diagram of the pressure relief water tank described in the present utility model.

[0015] List of Figure Symbols:

[0016] 1. Blower, 2. Pressure switch, 3. Pressure relief tank, 4. Differential pressure gauge, 5. Pressure relief valve 1, 6. Pressure relief valve 2, 7. Pipe 1, 8. Pipe 2, 9. Dome, 10. Control valve. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0018] As shown in the figure, the utility model describes a large-scale LNG cryogenic storage tank dome pouring pressure-maintaining safety relief device, which includes a blower 1, a pressure switch 2, a pressure relief water tank 3, a differential pressure gauge 4, a pressure relief valve 1 5 and a pressure relief valve 2 6, which are arranged outside the cryogenic storage tank. Two U-shaped pressure gauges are equipped on site, one leading out from the gate opening and the other leading out from the dome perlite nozzle. The display panels are both placed at the gate opening for easy observation.

[0019] The blower 1 is connected to the cryogenic storage tank via pipe 1-7, and the pressure relief water tank 3 is connected to the cryogenic storage tank via pipe 2-8. Pipe 2-8 is equipped with a pressure switch 2 and a pressure relief valve 1-5, which are arranged in parallel with pressure relief valve 2-6. The pressure relief water tank 3 is open or partially enclosed. The attached pressure relief valve 2-6 acts as a check valve to prevent water from entering the tank or backflow during pressure relief. Pressure relief valve 1-5 is a pressure relief valve; during normal pressure maintenance, pressure relief valve 1-5 is open and pressure relief valve 2-6 is closed. During pressure relief, pressure relief valve 1-5 is closed and valve 2-6 is open.

[0020] Pipe 2 8 enters the water tank near the bottom and cannot be connected. The water tank height exceeds the design pressure (water level 20cm).

[0021] Working principle:

[0022] Use blower 1 to pressurize the tank to within the design pressure range, close all valves and then turn off blower 1 to maintain pressure, and when the pressure is lower than the design pressure, open blower 1 and open control valve 10 to replenish pressure.

[0023] When the blower 1 is turned on, the pressure gradually reaches the design pressure, and then enters the pressure maintaining state. The water level of the pressure relief tank 3 does not change significantly, and the pressure differential gauge 4 can be compared to analyze whether the pressure differential gauge is accurate (the pressure differential gauge difference is the water level height of the water tank).

[0024] When the pressure rises or the pressure in the tank is too high due to weather conditions, the pressure relief valve 2 (6) can be closed and the pressure relief valve 1 (5) opened to release the pressure to the design pressure.

[0025] When the pressure in the tank is too high due to excessive pressure or weather conditions, all the water in the tank will be sprayed out and automatically relieved through the pipes inside the tank, and the pressure maintenance personnel will be prompted to perform emergency pressure relief to meet the design requirements (manually open the pressure relief valve 26). The pressure value in the tank is formed by the pressure sensor and the pressure value display device, which can accurately view the pressure data in real time, forming a new traditional and new pressure maintenance safety relief device, realizing semi-automation of the pressure maintenance and relief device.

[0026] The number of the blowers 1 in the present invention is two to ensure that the pressure meets the requirements.

[0027] It should be noted that the above content only illustrates the technical idea of ​​the utility model and cannot be used to limit the protection scope of the utility model. For ordinary technicians in this technical field, they can make several improvements and modifications without departing from the principles of the utility model. These improvements and modifications all fall within the protection scope of the claims of the utility model.

Claims

1. A large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device, characterized by: It includes a blower, a pressure switch, a pressure relief water tank, a differential pressure gauge, a pressure relief valve 1 and a pressure relief valve 2 arranged outside the low-temperature storage tank. The front end of the differential pressure gauge extends into the low-temperature storage tank. The blower is connected to the low-temperature storage tank through a pipe 1. The pressure relief water tank is connected to the low-temperature storage tank through a pipe 2. A pressure switch and a pressure relief valve 1 are provided on the pipe 2. The pressure relief valve 1 and the pressure relief valve 2 are arranged in parallel.

2. A large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device according to claim 1, characterized in that: There are two differential pressure gauges, which are respectively arranged at the bottom gate opening and the dome perlite nozzle of the low-temperature storage tank.

3. A large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device according to claim 2, characterized in that: The differential pressure gauge is a U-type differential pressure gauge.

4. A large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device according to claim 1, characterized in that: The number of the blowers is two.

5. The large-scale LNG cryogenic storage tank dome casting pressure-maintaining safety relief device according to claim 1 is characterized by: A control valve is provided on the first pipeline.

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