Liquid level measurement in vertical LNG storage tanks
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I would like to ask if anyone has experience with measuring the liquid level in 150 m3 vertical LNG storage tanks. Such tanks have only two pressure tapping points at the bottom; what type of level gauge is suitable for use in this case? For horizontal tanks, differential pressure can be utilized so that the transmitter is placed above the liquid surface and thus avoids contact with the liquid phase. But what about vertical tanks where the transmitter is at a higher position?
What’s the point of knowing how tall the tank is? Use a differential pressure gauge as usual. Come buy a gauge from me; I’ll draw a diagram and make a video to train you until you become an expert :P Perhaps you can also use a level gauge that works by subtracting the readings of two sensors. Even if the tank is 10,000 meters tall, it can still handle that situation
You already have two pressure tapping points; using differential pressure should suffice. If the density is constant, a pressure transmitter can also be used to measure the liquid level
Differential pressure gauges made by Chengdu Lanshi are used quite frequently
Rosemount has a transmitter called ERS, which should work for the situation you described. One set of transmitter includes two gauges, with a cable connecting them in between (I believe it’s a regular shielded cable). No problem even if it’s higher; we can take a look
The pressure sensing tubes do lead from the insulation layer all the way to the bottom. The main reason is that LNG is at extremely low temperatures of over minus 100 degrees, and there’s a concern that the transmitters might not function properly. In horizontal tanks, the transmitters can be placed above the liquid level, and the liquid level can be measured indirectly through the vaporization of LNG. However, with vertical storage tanks, this isn’t possible; it seems that liquid level transmitters at the liquid contact point using ERS technology also cannot be used in such cases
Since natural gas is a hazardous chemical subject to strict regulation and constitutes a major source of danger, a liquid level remote transmission system is installed
It should work; you can call Emerson to ask
A differential pressure transmitter will do; modern differential pressure gauges can measure pressures over several dozen meters without any problem