Is it necessary to evacuate the vapor phase when unloading propane and butane?
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This post was last edited by Gray Trail 01 on 2016-11-15 at 15:20. When unloading propane and butane, a compressor is used to draw the gas phase inside the tank into the truck for unloading. When there is no liquid phase in the truck, is it necessary to draw the gas phase from within the truck back into part of the storage tank?
Pressure extraction is required, but the remaining pressure in the tank truck must be at least higher than atmospheric pressure; generally, we draw the gaseous phase from the tank truck after unloading it back into the storage tank. There should be an operating procedure on site, right?
What a bizarre design. What was the gas in that storage tank initially? Nitrogen? Propane and butane are in liquid form when stored, so a transfer pump is sufficient for unloading them.
Is it weird? Liquefied gas is a mixture of propane and butane. Does the liquefied gas in your home exist only in liquid form and not in gaseous form?
There is both liquid-phase unloading and gas-phase unloading. Gas-phase unloading works in the manner described by the original poster, while for liquid-phase unloading, both the tank truck and the storage tank need to be connected
We only have a unloading pump; every time we unload, we need to relieve pressure from the propane tank. In summer, the pressure in the propane tank exceeds 9 kilograms even when the sprinklers are in use
How many storage tanks do you have? Can it be optimized by connecting the vapor line at the top of the tank to below? There must be some gas phase stored inside the tank.
Don’t be surprised – inside the storage tank, a balance is achieved between the gas and liquid phases; it’s not completely liquefied. Moreover, loading and unloading in this way is faster than using a liquefied gas pump to extract only the liquid phase. You can look up relevant information on this; it’s a quite standard design
Could you please give some directions on where to find the information, or the specific names of the materials? Recently, I have been working on tasks related to this area, and I’m completely confused regarding the time required for the evacuation process as well as the patterns of change in the pressure at the compressor inlet during evacuation; further study is needed. Thank you for reviewing.