Production Separator oil outlet line Scheme

[10815L]

Hi,
Problem; production operating pressure is 400 psi and oil flow is 2000BOPD, in future oil flow will increase to 8000BOPD.
we have two option to connect the oil outlet line with crude oil pump discharge and its discharge pressure is 300psi, in pump discharge option sound good but due to high separator pressure this oil still contain some associated gas and water and quality of crude may affected.
Option two, route the oil to existing separator and led down the pressure to 100 psi through control valve and further separator the oil and water from proposed oil line.
My question is which scheme is better and if connect with separator then ISS control system must be used.
Please provide some guidelines for both options.
Thanks
10815L

 

[TD2K]

Which is better?

What is the impact on the downstream equipment if the gas and water in the crude upstream of the separator isn't removed? Apart from operation issues, are there any contractual issues on crude properties you may no longer meet? Depending on the capacity of your separator and/or crude pumps, you could have to bypass a significant portion of the 6000 BPD additional crude.
Can you overpressure the pipeline as a result of installing a bypass around the separator and adding this high pressure stream to it?
Why was the separator installed in the first place? You don't install a separator to let crude down from 400 psig to 100 psig and then pump it back up to 300 psig to go down a pipeline for no reason. Aren't you defeating the purpose of that original design by bypassing the separator?
Not really part of your question but do your pipelines have capacity to handle 4x more flow?

 

[10815L]

TD2K,
Good advice, I will check for contractual status but over pressure we can fix it by providing the RO.
Thanks

 

[TD2K]

An RO does not prevent overpressure if a downstream valve is closed, everything pressures up to the supply pressure.