TOKYO GAS TOP > Corporate Information > Approach/Activity > Technical development > Earthquake disaster prevention & stable supply > Liquid Density Meter for LNG Tanks

Liquid Density Meter for LNG Tanks

Objective


When LNG of one density is fed into a tank containing LNG of another density, the two may form different layers. This can result in the generation of a large quantity of boil-off gas (BOG) when one layer suddenly disappears, a phenomenon known as “rollover.” LNG tank liquid density meters are therefore used to monitor the LNG inside tanks to prevent rollover from occurring.
 
Liquid density meter for new tanks
 

Liquid density meter for existing tanks
 
 
 
 

Functions


The LNG tank density meter can measure the density and temperature of LNG at all levels by means of a density sensor that moves up and down in the tank. They are of two types: one for new tanks, and another, which uses a tank’s reserve nozzle, for existing tanks.
 
Components of liquid density meter for existing tanks
 
 
 
 

Specifications


Specifications of liquid density meter
ITEMS SPECIFICATION
Operating temperature -170℃ to 50℃
Maximum tank depth 70m
Tank connection aperture New tanks: 12inExisting tanks: at least 3in
Measurement range 400 to 500kg/m3
Repeatability ±0.1kg/m3
Explosion proof structure Exia II AT3
This product is only sold in Japan.

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