0 votes
67 views

Liquefied Natural Gas (LNG) storage temperature at -161°C (-256°F)

asked May 11, 2016 in Engineering by jakangaru (2,010 points)
Hello, the specified Liquefied Natural Gas (LNG) storage temperature is at -161°C (-256°F) per specification. My question is that what happens if the process looses the temperature control to maintain -161°C (-256°F)? Are there steps to mitigate that from happening?

1 Answer

+1 vote
answered May 12, 2016 by josvanden (3,240 points) | selected May 13, 2016 by jakangaru
 
Best answer
In spite of insulation on tank, it will see some heat transfer into the tank, which will result in vaporization of LNG. This gas is called boil of gas (BOG). This gas can be re-liquefied by compressing and sending it to BOG condenser where LNG will come in contact with compressed gas and re-liquefy it. This is common process to maintain LNG in liquid state both onshore and on LNG tankers during transportation. Cases where BOG rate is too high gas will be flared.
commented May 13, 2016 by jakangaru (2,010 points)
Thanks for clarification.

However, I’m still wondering what keeps the temperature to stay at -161°C (-256°F)? Does the system have the refrigeration surrounding the tanks to maintain the temperature?
commented May 13, 2016 by josvanden (3,240 points)
No, it’s the way the tanks are constructed with insulation. As long as there is no significant heat input into the tanks it stays at -256F.

There are only few LNG tank Companies that can construct those type of tanks. It is made from specially constructed technology that can keep the temperature pretty constant.
...