pressure or vacuum

[MikeEFix]

Problem:
Transfer 10k gallons of contents from one tank to another tank in 20min.
With contents velocity not exceeding 10ft/s

Assumptions: (Tanks and piping)

Both source and destination tanks have 11’ dia and 15’ straight side with ASME dish top/bottom heads rated at 75 psig / full vacuum. And are at the same elevation 20’ apart under 0 psig

A 6” sch 10 pipe from the bottom center outlet of one tank to bottom center of the other connects the tanks. The length of the 6” pipe is 20’

Assumptions: (Contents)
1500Cp
1.1 Sg
Contains 5% free Vinylidene Chloride

Contents is shear sensitive and cannot be pumped in the conventional sense. It will have to pushed or pulled or a combination of each

By opening the valve on the 6” bottom connecting line, gravity will push 1/2 the contents to the empty tank.
The vapor space in the destination that the content displaces is returned to the source tank via return line connecting the two tanks at the top.

I need recommendations as to what method to use to transfer the remaining contents.

 

[MikeEFix]

Assuming the system is closed, if all the contents are transferred via vacuum/pressure will the tanks (pressure/vacuum) equilibrate to 0 psig?

I’m asking this with respect to the amount of space under vacuum and the amount of space under pressure at the end of the transfer

 

[mizzoueng]

How about a siphon?

 

[iainuts]

Assuming the system is closed, if all the contents are transferred via vacuum/pressure will the tanks (pressure/vacuum) equilibrate to 0 psig?

Once you move all the contents from one tank to the other, you'll need to also move all the vapor in the opposite direction in order for the pressure in the tanks to be equal. It will be the same pressure after this operation than it was prior to this operation.

Are you talking about pressurizing one tank with vapor from the opposite one?

 

[25362]

To mizzoueng,

What happens to the siphon when the level in the receiving tank is higher than in the delivering tank ?

 

[mizzoueng]

just thinking aloud, really haven't had a chance to really get into this topic yet.

 

[Yorkman]

MikeEfix,
What Katmar suggests is the same method I've used to move 8,000 lbs of R-22 liquid refrigerant from the 4000 ton evaporators to the refrigerant receiver at the Denver International Airport central Chiller Plant. I don't know how these vapors react or what thier boiling/flash temps. are but if they are reasonably low the procees is very effective.
With the R-22 refrigerant, we hook the suction of our transfer compressor to the top of the empty tank, and the discharge of the compressor to the top of the liquid tank. The charge of the liquid can be move in about 45 min. to 1 hour. After the liquid has been transfered we switch connections and draw vapors from the remainder of the liquid tank and discharge them through a condenser to the transfer tank. R-22 has a low boiling point so this is'nt too hard. I don't know the particulars of your liquid.


I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI

 

[Yorkman]

One last thought to use Katmar/pressure differential method you will need to make sure any vapor equalization lines are closed so that you can produce and maitain the pressure differential.

I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI