Some weeks ago we seen some cracks in the FCC expander blades in one of our FCC units. Tha cracks appeared suddenly, from one month to another.
The fresh catalyst addition rate are very low, so catalyst turnover is slow. It has provoked the ageing of our e-cat inventory. We have measured the attrition of the e-cat, with Jet Cup method (Davison Index), and we have been a deacrease from 2-3 to 1-2. My question is if this decrease in DI of the e-cat (harder catalyst) could be resposible for the mechanical problem in the expander.