Finger type slug catcher size doubling

[teomante]

For a Gas Treatment Plant, at the inlet of the plant coming with multiphase pipeline, there is a 850 m3 capacity finger type slug catcher after the pig receiver. In the rest of the system, there are mainly gas dehydration, condensate separation & stablization, export gas compression, HP and LP flares, MEG and TEG regeneration, water treatment sub-systems.
The Owner decided to increase the liquid slug size of slug catcher from 850 m3 to 1650 m3. Could you please advise which kind of other connected sub-systems and units can be affected from this increase? What will be the possible results on sub-systems on size or capacity manner? Will there be any increase on their capacity or size?

Thank you.

 

[JOHN T SMALL]

In order to assess the impact of this major change upon the rest of the plant, you need to know the new flow rates of gas, oil and water, (peak, average and minimum), and what are their physical properties. My advice would be to press the Owner for this information. The Owner´s project representative may not understand this requirement, in which case you need to interrogate others in the organisation- plant process engineer, pipeline engineer, reservoir engineer. Fun times ahead! Good luck!

 

[georgeverghese]

The required capacity of other subsystems may or may not be affected. The slugcatcher merely provides surge capacity for liquids arriving at the plant. Liquid arrival rates from incoming pipelines will be highest during pigging and during steep flow ramp up.
Ask the plant owner for the process design study documents that narrate the derivation basis for this increase in SC holdup to 1650m3 to get definite answers to your queries. The plant owner should not expect you to know what to do next merely by stating that SC capacity is to be increased without providing all design study documents.