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Catalyst Losses

When troubleshooting catalyst losses, describe cases where a unit shutdown was imminent (e.g., severe cyclone failure) if the losses could not be stopped quickly? Give recommendations for avoiding shutdowns due to excessive catalyst losses?

There are a number of scenarios that can lead to a unit shutdown due to excessive catalyst losses. Generally, inability to maintain regenerator bed level leads to an imminent unit shutdown. Since the stripper bed level is controlled with the spent catalyst valve any catalyst loss from the reactor or the regenerator is reflected in a loss of regenerator level. Refiners will face the decision to shut down whenever the catalyst loss is so high that:

Emtrol cyclone CatCrackerThere may be opportunities to mitigate the catalyst loss and delaying the need for shutdown. The delay would allow the refiner to troubleshoot and develop corrective action plans for staying on-line and keeping operating costs down.

The refiner could consider:


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In RefComm® Past Presentations, find these related articles.

Troubleshooting Catalyst Losses in the FCC Unit

Twenty Questions Identify Probable Cause of High FCC Catalyst Loss

Monitoring Mitigating and Troubleshooting FCC Catalyst Losses

Abnormal catalyst losses, coking/fouling at RFCCU main fractionator bottoms.

Avoiding FCCU Emergency shutdowns

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Posted by: Paul R Orlowski

Paul Orlowski is General Manager for the Refining Community which includes,,, Resid Hydrocracking and SDA. They consult at refineries around the world. They've hosted 36 technical conferences around the globe, trained 1,000's and completed very beneficial consulting and troubleshooting projects. Paul co-founded Inc in 1998 with Gary Pitman. Evan Hyde later joined the team. Besides being an educator and software applications engineer, he worked 18 years at ARCO and BP refineries near Seattle, WA USA. Previously he worked for Science Applications International Corporation and Dealer Information Systems. In 2019 look for #RefComm Galveston Coking | CatCracking | Resid Hydrocracking and RefComm® Rotterdam Coking | CatCracking. In 2020 Galveston; Gdansk, Poland and Rio de Janeiro, Brazil and Singapore.