I had our (KBC’s) delayed coking modeling expert take a quick look at this. Here are his thoughts;
In DC-SIM is that at higher Feed rates, even with constant COT, CFR and pressure, the reaction temperature in the Drum liquid holdup decreases. Due to more cracking moles at higher feed rates? The lower reaction temperature then results in higher coke yields.
If you send the file to us we can review the results and see if they are reasonable.
Sim Romero (firstname.lastname@example.org)