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Upgrading Cylones and Connected Diplegs

Concerns about changes in refinery FCC unit heat balances have surfaced more frequently as refiners increase resid content, which increases delta coke. In turn, this increase reactor temperature while reducing catalyst-to-oil ratio. Other unit operating factors have been receiving closer scrutiny in order to better optimize unit operations. Some of these factors include monitoring the various sources of coke, such as catalytic coke, requiring more careful scrutiny of the cyclone separators and diplegs, along with riser termination devices (RTDs) into the reactor.

FCCU cyclones with riser termination CatCracker

Mechanical enablers available to improve the unit heat balance and overall operational efficiency include feed nozzle improvements, torch oil nozzles, RTDs, and connected rotating equipment that need to be considered for optimizing performance of resid FCC units and high olefins FCC units.

This goes without saying that process objectives have put into question the current mechanical versatility of many existing FCC units. The substantial mechanical infrastructure involved in FCC operations focuses on the FCC reactor, regenerator, gas concentration unit and linked main air blowers.

In one of the several FCC sessions starting on May 2 at the RefComm Galveston refining conference, Christopher Dean concentrated a substantial amount of time solely on the unit’s cyclone separators and connected RTDs.  Changes in feedstocks and product objectives being what they are, such as towards more olefins, we may see more suppliers providing more options to improving circulation in the FCC with these assets.  The first two days of RefComm features training courses.  The next two days include presentations, panels, discussion and exhibition with FCC specialists Alan English (LinkedIn) and Chris Dean (LinkedIn) MC’ing the event.

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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.