Patent Document ID: 9850434
Application ID: 14953674
Patent Flag: 1

Claim One:
1. A method of predicting coke deposit formation tendency in a riser of a fluid catalytic cracking unit having a feed injection/catalyst mix zone in the riser, operating with a heavy hydrocarbon oil feed to the feed injection/catalyst mix zone, comprising: applying a model to calculate determining both (a) A theoretical riser mix zone temperature and (b) a theoretical hydrocarbon feed dew point from a plurality of factors comprising: a volumetric flow rate and a temperature for the feed to the mix zone, an injection steam mass flow rate and a temperature for a steam feed to the mix zone, a catalyst circulation mass flow rate to the mix zone from the regenerator and a temperature of the catalyst, a weighted average boiling point of the feed, and a riser pressure in the mix zone; applying a linear regression analysis to predict a margin between the theoretical hydrocarbon feed dew point and the mix zone temperature as a function of the plurality of factors, and correlating the margin with an amount of unvaporized feed, if any, under a set of operating conditions for the fluid catalytic cracking unit.