Cryogenic liquid storage tank is specially tank used for the storage of LNG. It is a kind of special equipment that has great significance
to public security. To achieve the desired effect in thermal insulation, the tank’s thermal insulation structure adopts
high-vacuum multilayer insulation or vacuum powder insulation. The storage tank consists of inner vessel and shell.
The inner vessel is mainly made of austenitic stainless steel S30408 which has outstanding cryogenic performance; and the outer shell adopts Q345R steel plate which is specially made for pressure vessel; The vacuum layer between
the inner and outer wall is filled with dried expanded perlite (pearlife) or the inner vessel is covered with heat insulation composite paper,
and the vacuum layer is also made degreasing, rust removal, rinsing and drying treatment strictly in accordance with related standards,
which guarantees the vacuum degree in the interlayer when the tank is sealed.
LNG is an abbreviation for liquefied natural gas. The main ingredient is methane. LNG is colorless, odorless, non-toxic and non-corrosive. Its volume is about 1/625 of the volume of gaseous natural gas. The weight of LNG is only about 45% of the same volume of water. The calorific value is 52MMBtu/t (1MMBtu=2.52). ×10^8cal).
LNG is short for Liquefied Natural Gas.
Formation: The natural gas produced by the gas field is first purified and then liquefied by ultra-low temperature (-162 ° C) atmospheric pressure to form liquefied natural gas.
The critical temperature between LNG gas and liquid under normal pressure is -162 °C”
The most commonly used standard in LNG manufacturing is the American Petroleum Institute (API) 620.
The six advantages of LNG
1) LNG volume is 624 times smaller than natural gas of the same quality, so it is convenient to transport LNG to places where there is no natural gas.
2) LNG has high storage efficiency and a small footprint. In the province of investment, 10m3LNG storage capacity can provide 10,000 households with one-day living gas.
3) As a high-quality vehicle fuel, LNG has high octane number, good antiknock performance and long engine life compared with gasoline. Fuel costs are low. Good environmental performance and other advantages. It can reduce HC in gasoline vehicle exhaust by 72%, NOx by 39%, CO by 90%, and SOx and Pb to zero.
4) The latent heat of LNG vaporization is high, and the cooling capacity in the liquefaction process can be recycled.
5) Since the density of LNG vaporization is very low, only about half of the air, a slight leak immediately spreads out without causing an explosion.
6) Because the LNG component is purer, burns completely, and produces carbon dioxide and water after combustion, it is a good clean fuel, which is conducive to protecting the environment and reducing urban pollution.
The main use of LNG
1) It is safe, convenient, fast and less polluting for use as a clean fuel for urban residents.
2) Use as a substitute for automotive fuel. LNG is used as fuel for automobile engines. The engine only needs to be properly changed. The operation is not only safe and reliable, but also low noise and low pollution. Especially in today’s increasingly strict emission regulations, the exhaust gas is obviously improved in vehicles with LNG as fuel. According to the data report, compared with compressed natural gas (CNG), LNG vehicle fuel cost is 20% lower and 2/3 lighter than medium and medium-duty vehicles under the same stroke and running time conditions. The cost of a combustion system unit is also at least 2/3 lower. It can be shown that liquefying natural gas and storing it in liquid form is the most cost-effective way to promote its use in transportation fuels.
3) As a cold source for the production of fast-cooling foods, as well as low-temperature pulverization of plastics and rubber, it can also be used for seawater desalination and cable cooling.
4) As an industrial gas fuel, it is used in glass bulb factories, glass factories and other industries.