hexane water separator system

[shi2shi]

Hi
i am looking at a small vessel(A) design for hexane as liquid( capacity 30 litres).vessel A is connected to another vessel B operating at atmospheric pressure. Vessel A has a vent line running via a condensor. lastly it has another nozzle for pumping the hexane via a pump.
capacity of vessel 40 litres. Curently no relief valves or Bursting discs have been considered.

does vessel A need to be pressure rated?

 

[dcasto]

You need to look at modes of failure that could send hexane and other fluids to vessel A. Then look at what capacity the line between vessels A and B can be transfered and not allow the pressure in vessel A to go above 15 psig. You'll also have to calculate the pressure drop of the fluids exiting vessel B and take that into account also.

 

[shi2shi]

Is 15psig a standard condition for a pressure vessel? What do you mean by ‘ what capacity the line between vessels A and B can be transfered ‘

Precautions taken to ensure Vessel A is not pressurised:
1) Level control which will switch on a pump and pump out hexane into another storage tank.
2) Any build up of hexane vapour flows up through a vent line sitting directly on top of the vessel. There is also another vent pipe on vessel B ( this will ensure any vapour build up is sent to the condenser.)
3) Vessel A is expected to take at least more than a month to fill up.
4) Vertical sight glass on both vessels will provide liquid height.
Vessel B has two exit points. One allows water to drain out by gravity. This same system ensures that vessel B never achieves liquid above a certain height. The second exits into vessel A such that there is a connecting line between A and B to allow hexane to OVERFLOW into vessel A. Therefore this line is level. And has a NRV on it


Do these steps sound enough….