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In cyclemax of of CCR unit, we had issues with fines collection for around 15 days. But thereafter when we performed the fines collection 350 kg of fines was removed. This surprisingly seems to be large amount. Is it due to new catalyst ? What should be the real amount of fines collection per day?
What could be the reasons for higher fines generation?
 
Answers
19/08/2015 A: Azhar Kazi, Honeywell UOP, azhar.izak@gmail.com
Usually Fines make is around 1 -1.5 kg/day, and its generation depends a lot on your lift line velocities, both Spent and Regen Lift Lines, major erosion occurs in the lift lines if very high velocities are encountered, UOP recommends a range for all the 3 Lines, Regen, Spent and Elutriation, try to make sure your Lift Line velocities are within the range. 350 kg is a big amount imagine the Fresh catalyst you will need to enter and catalyst loss you will face if this continues.
14/07/2015 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
It is not unusual to get some extra attrition with new catalyst. If you have some of you might want to test the hardness index to make sure it is within the specs. You might also check to make sure that there aren't any valves for purge gas that inadvertently were left open. A jet of gas like N2 into the catalyst can also lead to increased attrition.
29/06/2015 A: Farid Q Q, Indian oil corporation Ltd, faridulqadar@gmail.com
Since you've mentioned that it is a new catalyst then it can be due to the way catalyst loading was done. If loading for all the stacked reactors was done from top of the reduction zone then the catalyst settling in bottom most reactor would have suffered highest impact velocity and attrition leading to higher fines generation. As you go up in the stacked reactor configuration fines generation is reduced due to lesser impact velocity and attrition. When unit goes on stream and catalyst circulation starts these fines get removed gradually from the system.