Product Description

Brand  He Guo Group  Model  CFW-60/0.8

Material: Stainless Steel, Diameter: 2916mm

Application Range    -162℃    Volume    60000L

Wall Thickness: 8mm, Outer Dimensions: φ2916*14929mm

Origin: Shandong Heze

Heze LNG Storage Tank, Low Temperature Oxygen/Nitrogen/Argon Carbon Dioxide Storage Tank, 60 Cubic Meters LNG Tank

Low-temperature LNG tanks are high-vacuum insulated stainless steel pressure vessels designed for the storage, transportation, and use of liquefied natural gas. The tanks are manufactured in accordance with GB18442 standards and are used for reliable and cost-effective transportation and storage of cryogenic liquids, as well as for on-site storage and supply of cryogenic liquid gases across a wide range of applications.

With the development of low-temperature liquid storage and transportation, the insulation technology for low-temperature containers is increasingly refined. To maintain the storage and transportation of low-temperature liquids as well as the temperature of low-temperature refrigeration, it is necessary to adopt insulation measures for the low-temperature environment. Only under insulated conditions can low temperatures be maintained. Insulation can reduce vaporization loss, or create conditions for long-distance transportation of low-temperature liquids.

Low-temperature insulation methods can be divided into two major categories: general insulation and vacuum insulation.

(1) Standard insulation is an older, traditional method of insulation, which involves applying solid, porous insulating materials to the outer sides of equipment, containers, and pipes. The voids within the insulating material are filled with air or other gases under atmospheric pressure.

(2) There are three basic types of vacuum insulation: high vacuum insulation, vacuum powder insulation, and vacuum multilayer insulation.

Principles of Pressure Increase and Decrease in LNG Storage Tanks

Boost Pressure:

As LNG is used, the liquid level inside the tank continuously decreases, and the increased gas phase space causes the tank pressure to drop. The flow rate of LNG gradually slows down until it stops. Therefore, during normal operation, it is necessary to continuously replenish gas into the tank to maintain the pressure within a certain range. This process is called pressurization. As shown in the diagram, the tank pressurization is achieved by an automatic pressurization system consisting of an automatic pressure regulator and a small air-temperature gasifier. When the tank pressure falls below the set value of the automatic pressurizer, the regulator opens, and the liquid inside the tank slowly flows into the pressurization gasifier due to the liquid level difference. The gas produced by the vaporization of the liquid flows through the regulator and the gas phase pipe to replenish the tank. The continuous replenishment of gas raises the tank pressure, and when it exceeds the regulator's set value, the regulator closes. At this point, the pressure inside the pressurization gasifier will prevent further liquid inflow, and the pressurization process ends.

Pressure Relief: (Overpressure Protection)

LNG can slowly evaporate during storage due to heat loss from the storage tank's environment, leading to a gradual increase in tank pressure, which can ultimately compromise tank safety. Therefore, it is necessary to control the pressure limit by releasing the gas inside the tank. This is done by installing a pressure regulator on the gas phase pipeline of the storage tank. When the tank pressure rises to a set value, the pressure relief valve opens slowly to release the tank gas. When the pressure drops back below the set value, the automatic regulator closes automatically. It should be noted that the regulator referred to here is not the commonly used gas regulator. Generally, regulators rely on the operation of the control valve at the outlet end, but this regulator relies on the operation of the control valve at the inlet end, similar to the commonly used vent valve, and it must also withstand low temperatures. The released gas is typically not released into the atmosphere; instead, subsequent processes will recover and utilize it. This portion of the gas is abbreviated as BOG.

Heze LNG Storage Tank, Low-Temperature Oxygen/Nitrogen/Argon Carbon Dioxide Storage Tank, 60 Cubic Meters LNG Tank

山东LNG储罐厂家 30立方卧式LNG储罐 真空天然气储罐

LNG Tank Characteristics Requirements

Low-temperature resistance

The boiling point of liquefied natural gas at atmospheric pressure is -162°C. Therefore, LNG storage tanks require excellent low-temperature resistance and insulation properties.

(2) High safety requirements

Due to the storage of low-temperature liquids inside the tank, in the event of an accident, the refrigerated liquid would evaporate in large quantities, with the vaporization amount being approximately 625 times that of the original refrigerated state, forming an explosive mixture in the atmosphere. Therefore, it is required that the tank be constructed with a double-walled structure and utilize the containment concept. In the event of a leak in the first layer of the tank, the second layer can completely contain the leaked liquid and evaporated gas, ensuring storage safety.

(3) Special materials.

The inner tank must be capable of withstanding low temperatures and is made of Austenitic stainless steel, while the outer cylinder is constructed from Q345R ordinary low-carbon alloy steel plate.

(4) Strict thermal insulation measures.

Due to the maximum temperature difference of up to 200℃ between the inside and outside of the can, the can must have excellent insulation properties to maintain an internal temperature of -160℃. High-performance insulation material should be filled between the inner and outer shells. The insulation material at the bottom of the can must also possess sufficient load-bearing capacity. (5) Good seismic performance

General building seismic requirements are to crack under specified seismic loads but not collapse. To ensure the safety of storage tanks under unexpected loads, they must possess excellent seismic performance. Ensure that the tank does not sustain damage under the given seismic intensity. (6) Strict construction requirements

The tank welds must undergo 100% magnetic particle inspection (MT) and 100% vacuum tightness testing (VBT). Strict selection of insulation materials is required, and the prescribed procedures must be followed during construction.

2. LNG Tank Structure

The low-temperature storage tank is a double-layered structure. The inner tank stores low-temperature liquids, withstands the pressure and low temperature of the medium, and is made of low-temperature-resistant alloy steel (0Crl8Ni9). The outer shell serves as the protective layer for the inner tank, maintaining a certain distance from the inner tank to form an insulating space. It bears the gravitational loads of the inner tank 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 high vacuum is drawn. The evaporation rate of the low-temperature storage tank is generally less than 0.2%.

Main components include: outer can, inner can, inner lining support, insulation layer, upper and lower liquid inlet pipes, upper and lower liquid level pipes, vapor pipe, overflow pipe, discharge pipe, as well as safety accessories and instruments, etc.

山东LNG储罐厂家 30立方卧式LNG储罐 真空天然气储罐