Processing cheaper, lower-quality feeds such as resi- dues and difficult-to-crack materials Increasing conversion and improving the yield structure by reducing dry gas and feed coke Maximising operating severity by unlocking compres - sor and heat-balance constraints. The new nozzles have been implemented and audited at several assets, where the results have included: • 39°F (22°C) reduction in regenerator bed temperature • 3.7% increase in gasoline yield • 15% reduction in dry gas and a 2.5% increase in feed rate. The technology complements the benefits already pro - vided by FCC feed hydrotreaters and expands the options for upgrading an FCC-PT unit to optimise an FCC-PT–FCC unit complex. References 1 Kunz K, Ludolph R, Carroll C and Cui Z (2016), Developing Feed Nozzle Technology from an Owner/Operator Perspective, AFPM Cat Cracker Seminar, Houston, USA, CAT-16-8. Todd Foshee is FCC Licensing Technology Manager, Shell Catalysts & Technologies. He leads the efforts for licensing Shell’s FCC technol - ogy to third-party customers and is part of a team that provides the process design for FCC projects to both Shell and third-party clients.
dry gas yield are observed. As a result, the catalyst-to-oil (cat/oil) ratio increases, and liquid yields improve. With a lower WGC loading, there is room to increase riser tempera- ture. A temperature rise of 10°F (6°C) increases conversion by 0.5 wt% and shifts the yield structure to a lighter distribu- tion, all within the wet gas compressor capacity. Table 5 presents the impact of upgrading the FCC feed nozzles to the latest Shell technology under FCC-PT EOR conditions. The upgraded feed nozzles improve the yield structure beyond what can be achieved through improve- ments in EOR feed quality in the FCC-PT. Under both SOR and EOR FCC-PT operating conditions, the Shell FCC feed nozzles are predicted to give additional improvements in yield structure and expand operating flex - ibility. The refiner can augment their FCC capability through reasonable capital investment while retaining the 32-month FCC-PT operating cycle and perhaps even extending the cycle. Furthermore, the added capability of the new feed nozzles also provides the opportunity to modify and optimise the catalyst system and reactor internals in the FCC-PT, for example, to pursue opportunity feeds. Conclusions The proprietary Shell Max Atomisation Feed Nozzle tech- nology provides a low-cost opportunity for refiners to max - imise margin by:
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