Product Description

Brand  Hegu Group  Model  CFW-30/0.8

Material: Stainless Steel, Diameter: 2916mm

Application Range    -162℃    Volume    30000L

Heat Exchange Area - See drawing m², Ambient Temperature - See drawing °C

Wall Thickness: 8/10mm, Outer Dimensions: 2916*8289mm

Origin: Shandong Heze

30立方立式lng储罐 卧式LNG储罐 低温天然气储罐厂家

The low-temperature storage tank is a double-layer structure, with the inner shell storing low-temperature liquids, withstanding the pressure and low temperatures of the medium. The material of the inner shell is a low-temperature-resistant alloy steel (0Crl8Ni9). The outer shell serves as a protective layer for the inner shell, maintaining a certain distance to form an insulating space, bearing the gravitational loads of the inner shell and the medium, as well as the vacuum negative pressure of the insulating layer. The outer shell does not come into contact with the low temperature and is made of container steel. The insulating layer is mostly filled with mica sand, and a high vacuum is drawn. The evaporation rate of the low-temperature storage tank is generally less than 0.2%.

LNG Tanks by Capacity Classification

(1) Small (5-50 m³): Commonly used for civil LNG refueling stations and civil gas liquefaction stations, etc. (2) Medium (50-100 m³): Typically used for industrial gas liquefaction stations. (3) Large (100-1000 m³): Suitable for small-scale LNG production facilities.

(4) Large (10,000～40,000 m3): Used for base load and peak-shaving type liquefaction plants. (5) Extra Large (40,000～200,000 m3): Used for LNG receiving terminals.

LNG tanks are categorized by shape

Spherical: Generally used for medium to small capacity storage tanks. (2) Cylindrical: Used in storage tanks of various capacities. LNG Storage Tanks are Categorized by Placement (1) Above Ground: Located on the ground. (2) Underground: Located beneath the ground.

Determination of Design Pressure and Calculated Pressure

Currently, the majority of 100m3 vertical LNG storage tanks have a maximum working pressure of 0.8MPa. According to the regulations of GB150 "Steel Pressure Vessels," when the maximum working pressure of the storage tank is 0.8MPa, the design pressure may be taken as 0.84MPa. The filling coefficient of the tank is 0.95, and the net pressure of the liquid column after filling the inner tank with LNG is 0.062MPa. The absolute pressure between the inner and outer tanks is 5Pa, resulting in a calculated pressure of 1.01MPa for the inner tank.

The primary function of the outer tank is to securely fix the inner tank and insulation material in a suspended or supported manner, while forming a high-vacuum insulation layer with the inner tank. The loads acting on the outer tank are mainly the gravitational loads of the inner tank and the medium, as well as the vacuum negative pressure of the insulation layer. Therefore, the outer tank is an external pressure vessel, with a design pressure of -0.1 MPa.

Material selection for LNG tanks

During normal operation, the working temperature of the LNG storage tank is -162.3°C. Prior to the first use, the tank must be pre-cooled using liquid nitrogen at -196°C, making the design temperature of the tank -196°C. The inner tank must withstand both the working pressure of the medium and the low temperature of LNG, necessitating that the inner tank material possesses excellent comprehensive mechanical properties at low temperatures, particularly good low-temperature toughness. Therefore, the inner tank material is selected as SS30408. Based on the calculated pressure of the inner tank and the selected material, the calculated thickness and design thickness are 11.1mm and 12.0mm, respectively. As a normal temperature external pressure vessel, the outer tank material is chosen as low-alloy steel 16MnR, with a design thickness of 10.0mm.

LNG Storage Tank Takeover Design

Ports on the inner tank of the storage tank include: inlet liquid port, outlet liquid port, liquid discharge port, vapor port, overflow port, upper level gauge port, lower level gauge port, and 8 process manholes. The material of the pipes on the inner tank is all OCrl8Ni9.

For easy regular measurement of vacuum and evacuation, a vacuum evacuation port is provided in the lower封 head of the outer cylinder (the port is sealed after evacuation). To prevent vacuum failure and the leakage of the inner cylinder medium into the outer cylinder, a explosion-proof device is set up in the封 head of the outer cylinder.

30 Cubic Vertical LNG Tanks, Horizontal LNG Storage Tanks, Low Temperature Natural Gas Storage Vendors