Can LNG flow by gravity into LNG tankers?
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Can LNG flow naturally into the LNG tank truck (with the gas phase in the tank truck connected to the LNG storage tank)? The operating pressure of large LNG tanks is generally 15 KPG, but the liquid level is quite high. May I ask if LNG can flow by gravity into the LNG tank truck? Thank you! Should we also distinguish whether the static head plus operating pressure (15 kPa) is greater than the pressure loss in the pipeline?
Generally not; it is necessary to start the pump, as there is residual pressure in the LNG tank truck
Theoretically, it is feasible; once the gas-phase pressure is balanced, LNG can flow by gravity into the LNG tank truck. The lowest liquid level in the LNG tank must be above the top of the LNG tank truck.
It’s only a theoretical possibility! ! ! ! ! ! ! ! ! ! ! ! ! !
Won’t a portion of the natural gas vaporize? Be aware that the pressure inside the tank of the transport vehicle will increase, and it might not be possible to get through
In fact, there is a one-way valve between the tank truck and the storage tank.
It’s possible to go, but it’s not advisable. Our company has LNG. The main reasons are as follows: 1. The self-pressurization speed is slow, resulting in delayed loading. 2. As LNG partially vaporizes inside the tank of the transport vehicle, the pressure increases; the lower the liquid level, the slower the pressurization process, until ultimately the tank cannot be filled to the required volume or to meet the customer’s specifications. 3. Prolonged exposure to such conditions poses various safety risks, including carelessness on the part of operators. Starting a pump doesn’t consume much electricity either.
:):):) It is still recommended to add a pressure device, as the effect will be more noticeable
If the entire loading system, along with its auxiliary systems, is in an environment with low thermal insulation, then gravity-fed flow will certainly work without problems; the only difference will be the speed. But it’s not easy to make the entire system airtight; there will always be some slight vaporization, so it’s better to have a pump or something.
It’s not done that way; otherwise, it would take years
It’s still reliable to use pumps and compressors. Self-flowing has never been seen in actual production; it probably doesn’t save much electricity, is time-consuming, and moreover, the flow isn’t thorough enough.