almostbroken
Petroleum
I have heard but not found any documentation that says the use of multiple valves during a blowdown are not allowed.
The problem is a single valve for blowing down a large gas volume as found in a gas plant does result in a larger flare system that any other case.
I would like to have the first valve sized for the second largest case and let the peak pressure bleed off. At some point often just a few seconds the pressue has been reduced to the point that the flow is starting to fall dramatically.
Then I would size a second valve (perhaps with a RO) for that pressure such that the combined flow rate does not exceed the original flow. I would have this one either open with a fusable link or have an independant air supply so that loss of air is not an issue.
Does anyone know of anything within API or other common guidelines that suggest this is not acceptable?
Almost Broken
The problem is a single valve for blowing down a large gas volume as found in a gas plant does result in a larger flare system that any other case.
I would like to have the first valve sized for the second largest case and let the peak pressure bleed off. At some point often just a few seconds the pressue has been reduced to the point that the flow is starting to fall dramatically.
Then I would size a second valve (perhaps with a RO) for that pressure such that the combined flow rate does not exceed the original flow. I would have this one either open with a fusable link or have an independant air supply so that loss of air is not an issue.
Does anyone know of anything within API or other common guidelines that suggest this is not acceptable?
Almost Broken
