CO2 Liqufaction Flow Issues

[co2abc]

After inheriting a CO2 liquefaction plan, I am noticing a few design issues. It is difficult to get flow from the reboiler to the storage tank. Can I do this using just differential pressure or is a displacement pump required?

 

[horacio Torres]

The PFD comes from a simulator or is a screen from a DCS. In both cases, which is the simulator? or is a DSC a Yokokawua ????

Horacio

linkedin.com/in/horacio-torres-molina-429a7b1b

 

[georgeverghese]

But MV-150 shows 41% open only - if there was difficulty flowing through from reboiler to 50ton tank via chiller HEX 141, then reboiler LCV would be close to 100% open?

 

[co2abc]

George, even with MV-150 fully open there is a low flow between the two tanks.

 

[georgeverghese]

At 20bar abs / -30degC downstream of the reboiler LCV going to the storage tank, it is subcooled liquid CO2 according to P-h diagram for CO2 ( subcooled by 10degC at 20bar abs), so no problems there. So temp control at rundown chiller HEX is probably working as it should.
Could there be an internal leak between refrigerant side and liquid CO2 side in this HEX? Can you tell us more about this chiller and refrigerant ?
a) Refrigerant description, composition, operating pressure range and temps in chiller HEX
b) Liquid Co2 operating press range, temps in chiller HEX
c) Chiller configuration, TEMA type, design press / temp

 

[pierreick]

Hi,
To support your investigation a handbook about CO2.
As suggested check for abnormalities around equipment using the diagram and tables given to you.
Always start with big picture before going to details.
BTW did you check the process book and data from start up? Mass balance, operating T, P, Flow), valves opening. E.T.C
This is very basic for a process engineer.
Pierre

 

[LittleInch]

Can you post the PFD and the P&ID as there are often lots more valves and connections than the schematic shows.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[LittleInch]

Also FIT 150 is the only flow figure in that schematic. If its not flowing to the tank where is is going? Or it doesn't exist?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.