Dear all,
I have a problem in designing a deethanizer column. The main task of this column is to separate light components (e.g. H2, ethylene and ethane) from a propylene/propane mixture. The feed contains about 6mole% propane, 2mole% lights and the rest is propylene.
My main problem is in determining column' diameter. I know that a jet flood of 80% is commonly assumed for determining column' diameter. But I came across an operating column with similar feed composition but different flow rate. After simulation of this operating column, I found out that it is designed based on jet flood of 35%. I mean the column can handle a much larger vapor flow rate. This column is operating properly. Downcomer back up and downcomer choke flood of this column are about 50%, based on my calculations.
So, I don't know if I should design my column based on jet flood of 80% or 35%?
I would very much appreciate your kind responses.