Gas Line, Worst Case Discharge
Gas Line, Worst Case Discharge
(OP)
I am trying to do a worst case discharge on a pipeline that is primarily gas. there will be a little bit oil compared to the gas in the system. 135 MMSCF and only about 5500 BOPD
The problem I am having is you have to take the volume of the pipeline, which is a 36" OD and over 360,000 feet long in the last leg when it come in from offshore. So I am coming up with a WCD over 80,000 bbls when the most the line will hold is about 30,000 bbls (Assuming it takes the gas 5 days to get to shore)
Does anyone know if there is an alternative version to use for gas pipelines
The problem I am having is you have to take the volume of the pipeline, which is a 36" OD and over 360,000 feet long in the last leg when it come in from offshore. So I am coming up with a WCD over 80,000 bbls when the most the line will hold is about 30,000 bbls (Assuming it takes the gas 5 days to get to shore)
Does anyone know if there is an alternative version to use for gas pipelines
Future PE Engineer
Pet project I am working on to help other engineers, not much yet hoping to get it grow as I learn more
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RE: Gas Line, Worst Case Discharge
You don't say anything about terrain or slopes or pressure or velocities or how you've calculated any of the figure so far
You will need to explain much more and attach a few sketches / profiles if you're going to get sensible responses.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Gas Line, Worst Case Discharge
For the WCD, you usually take the volume of the pipe and the amount that can flow through it before the shut down valves close and isolate the system. In a pure liquid line this is pretty easy. Now when a portion of that pipeline volume is gas how can I get a good estimate on the amount of liquid that is still in the pipeline
Future PE Engineer
Pet project I am working on to help other engineers, not much yet hoping to get it grow as I learn more
http://www.peexamquestions.com
RE: Gas Line, Worst Case Discharge
However unless your line is incredibly gently sloping in a continuous manner this will give a much higher figure than what could ever leak out as liquid generally doesn't like flowing up hill and will sit in the low spots.
You could find that the liquid in the line exceeds by some multiples of what your steady state rate is. Big lines running quite slowly can fill up with a lot of liquid. If your actual gas velocity drops much below 3.5 m/sec - 12 ft/sec then as a general start point you start to run into increased liquid hold up.
Is this closer to your issues?
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way