Hi there,
As part of designing an ethylene and propylene production plant from steam cracking, I am currently working on designing the deethanizer, demethanizer and one of the refrigerant cycles (part of the cold box). We have selected a front end de-ethanizer (dual Pressure) with front end hydrogenation as our column sequencing order.
Another member of the group is working on the cracking furnace and so I don't have feed composition currently. I'm a little lost with where to start. We are required to complete the following (for the demethanizer)
- Draw a PFD including control & relief streams - I assume this would just be columns +condenser and reboilers adjacent to it? - Is there extra equipment I'm forgetting?
- Mass and energy balances - Unsure on performing these? Given there is no reactions occuring just separations.
- Short cut - design to gain dimnesions - I feel the most suitable approach to shortcut sizing would be applying Fenske, Underwood, Gilliland and Kirkbride method - to calculate number of stages
- Application of thermodynamic models - I know that from using models e.g PRSV or SRK we could determine the relative volatitilites and understand the degree of separation.
I just think I'm a bit lost with where to start. I would really appreciate some help and guidance getting started.
Thanks
Jai