Producing Propylene by Dehydrogenation: explanation of the process

[RobinHud]

Hi,
I recently visisted a refinery to comission our S.G. / M.W. meter. I wanted to get a better undestanding of the process, but due to time limitations and language barrier I could only learn a little. The refinery (can I say the company name on this forum?) made propylene from propane using dehydrogenation. I was told that the M.W. measurement was particularly important for the three compressors.
Could somebody please explain the dehydrogenation process, what part the compressors play, and why the measurement is needed? Could the process run without this measurement?
I really appreciate any help you can give.
Thanks,
Robin

 

[blacksmith37]

Contractors that I am familiar with (Fluor, Foster/Wheeler , etc) provide ,with the operation manual and equipment drawings, a process description. On the other hand ,in some places like India, the unit supervisor may lock these away so that he is the only one that has the information.

 

[Pumpsonly]

For a chemical process, the mass of the feed stocks need to be in correct proportion. S.G /M.W are used for mass flow rate calculation in flow metering. Mass is constant irrespective of temperature and pressure.
M.W are used for gas flow measurement/control and surge control in centrifugal compressors.

 

[RobinHud]

Thanks. I have come to realise our M.W. measurement is being used for surge control (as you said Pumpsonly) and so I've now been able to google that and learn a bit more.