A clear case
for active filtration.

After an overnight analysis, Crystaphase identified the offending foulant as iron sulfide—a fairly common problem. Scanning Electron Microscopy (SEM) imaging confirmed our suspicion that it was entering the reactor as iron naphthenate, a soluble compound. This allowed the iron to bypass the filtration system before precipitating in the catalyst bed. By inadvertently adding catalyst above the distributor tray, the refiner had created a precipitation problem above the main bed.

Since the skim was already in process, we implemented a stop-gap solution—active filtration in a limited space above the catalyst. This would sustain the unit until its next catalyst change. It ran for another ten months and 12 days—a 66 percent increase in cycle length—which was within three days of what Crystaphase predicted. At this point, we configured an active-filtration solution built specifically around their unique precipitation issue.