Application: Selective and high conversion of a wide range of feedstocks into high-value products. Feedstocks include virgin or hydrotreated gasoils that may also include lube oil extract, coker gasoil and resid.
Products: High-octane gasoline, light olefins and distillate. Flexibility in unit operation allows for maximizing the most desirable product.
Description: The Lummus Technology process incorporates an ad-vanced reaction system, high-efficiency catalyst stripper and a me-chanically robust, single-stage fast fluidized bed regenerator. Oil is injected into the base of the riser via proprietary Micro-Jet feed injec-tion nozzles (1). Catalyst and oil vapor flow upwards through a short-contact time, all-vertical riser (2) where raw oil feedstock is cracked under optimum conditions.
Reaction products exiting the riser are separated from the spent catalyst in a patented, direct-coupled cyclone system (3). Product va-pors are routed directly to fractionation, thereby eliminating nonselec-tive post-riser cracking reactions and maintaining the optimum product yield slate. Spent catalyst containing only minute quantities of hydro-carbon is discharged from the diplegs of the direct-coupled cyclones into the cyclone containment vessel (4). The catalyst flows down into the stripper containing proprietary modular grid (MG) baffles (5).
Trace hydrocarbons entrained with spent catalyst are removed in the MG stripper using stripping steam. The MG stripper efficiently removes hydrocarbons at low steam rate. The net stripper vapors are routed to the fractionator via specially designed vents in the direct-coupled cyclones. Catalyst from the stripper flows down the spent-catalyst standpipe and through the slide valve (6). The spent spent-catalyst is then transported in dilute phase to the center of the regenerator (8) through a unique square-bend-spent catalyst transfer line (7). This arrangement provides the lowest overall unit elevation. Catalyst is
regenerated by efficient contacting with air for complete combus-tion of coke. For resid-containing feeds, a catalyst cooler is integrat-ed with the regenerator. The resulting flue gas exits via cyclones (9) to energy recovery/flue gas treating. The hot regenerated catalyst is withdrawn via an external withdrawal well (10). The well allows independent optimization of catalyst density in the regenerated cata-lyst standpipe, maximizes slide valve (11) pressure drop and ensures stable catalyst flow back to the riser feed injection zone.
The catalyst formulation can be tailored to maximize the most desired product.
Economics:
Investment (basis: 30,000 bpsd including reaction/regeneration system and product recovery. Excluding offsites, power recovery and flue gas scrubbing US Gulf Coast 2006.)
$/bpsd (typical) 2,400–3,500
9
Installation: Seventeen grassroots units licensed. Thirty-three units revamped, with five revamps in design stage.
Licensor: Lummus Technology, a CB&I company contact
PROCESSES INDEX COMPANY INDEX HOME
HYDROCARBON PROCESSING
®2011 Refining Processes Handbook
Copyright © 2011 Gulf Publishing Company. All rights reserved.
Fluid catalytic cracking (FCC)
Application: Selective conversion of gas oil feedstocks.
Products: High-octane gasoline, distillate and C3 – C4 olefi ns.
Description: Catalytic and selective cracking in a short-contact-time riser where oil feed is effectively dispersed and vaporized through a propri-etary feed-injection system. Operation is carried out at a temperature consistent with targeted yields. The riser temperature profi le can be op-timized with the proprietary mixed temperature control (MTC) system.
Reaction products exit the riser-reactor through a high-effi ciency, close-coupled, proprietary riser termination device RSS (riser separator system). Spent catalyst is pre-stripped followed by an advanced high-effi ciency packed stripper prior to regeneration. The reaction product vapor may be quenched to give the lowest possible dry gas and maxi-mum gasoline yield. Final recovery of catalyst particles occurs in cyclones before the product vapor is transferred to the fractionation section.
Catalyst regeneration is carried out in a single regenerator equipped with proprietary air and catalyst distribution systems, and may be oper-ated for either full or partial CO combustion. Heat removal for heavier feedstocks may be accomplished by using reliable dense-phase catalyst cooler, which has been commercially proven in over 65 units. As an alternative to catalyst cooling, this unit can easily be retrofi tted to a two-regenerator system (R2R) in the event that a future resid operation is desired.
The converter vessels use a cold-wall design that results in mini-mum capital investment and maximini-mum mechanical reliability and safety.
Reliable operation is ensured through the use of advanced fl uidization technology combined with a proprietary reaction system. Unit design is tailored to the refi ner’s needs and can include wide turndown fl exibility.
Available options include power recovery, waste-heat recovery, fl ue-gas treatment and slurry fi ltration. Revamps incorporating proprietary
feed injection and riser termination devices and vapor quench result in substantial improvements in capacity, yields and feedstock fl exibility within the mechanical limits of the existing unit.
Installation: Shaw and Axens have licensed 50 grassroots FCC units and performed more than 200 revamp projects.
Reference: Meyers, R., Handbook of Petroleum Refi ning Process, Third Ed.
Licensor: Shaw and Axens CONTACT
Copyright © 2011 Gulf Publishing Company. All rights reserved.
Fluid catalytic cracking
Application: To convert heavy distillates and residues into high-value products, including selective propylene production when required, using the Shell fluid catalytic cracking (FCC) process.
Description: In this process, Shell’s high-performance feed nozzle sys-tem feeds hydrocarbons to a short contact-time riser. This design en-sures good mixing and rapid vaporization into the hot catalyst stream.
Cracking selectivity is enhanced by the feed nozzles and proprietary riser-internals, which reduce catalyst back mixing while reducing overall riser pressure drop.
Riser termination design incorporates reliable close-couple cyclones that provide rapid catalyst/hydrocarbon separation. It minimizes post-riser cracking and maximizes desired product yields, with no slurry clean up required. Stripping begins in the staged stripper, equipped with high-capacity baffle structure.
A single-stage partial or full-burn regenerator delivers excellent per-formance at low cost. Proprietary internals are used at the catalyst inlet to disperse catalyst, and the catalyst outlet to provide significant catalyst circulation enhancement. Catalyst coolers can be added for more feed-stock flexibility.
Cyclone-systems in the reactor and regenerator use a proprietary design, thus providing reliability, efficiency and robustness. Flue gas cleanup can be incorporated with Shell’s third-stage separator.
Shell Global Solutions FCC technologies are proven reliability cham-pions due to simplicity of components and incorporation of Shell’s ex-tensive operating experience.
Installation: Over 30 grassroots units designed/licensed, including 7 to handle residue feeds, and over 30 units revamped.
Supplier: Shell Global Solutions International B.V. contact
To fractionator Close
coupled cyclones
Catalyst circulation enhancement
technology Advanced spent catalyst
inlet device
Cold-wall construction Staged
stripping
Riser internals
performanceHigh feed nozzles
Processes Index comPany Index Home
HYDROCARBON PROCESSING
®2011 refining Processes Handbook
Copyright © 2011 Gulf Publishing Company. All rights reserved.
Fluid catalytic cracking
Application: Selectively converts straight run and hydrotreated gasoils and residue feedstocks into higher value products using the UOP FCC process, the UOP Resid FCC (RFCC), the UOP PetroFCC process and UOP RxPro process.
Products:Light olefins (for alkylation, polymerization, etherification or petrochemicals), LPG, high-octane gasoline, distillates and fuel oils.
Description: UOP’s process uses a side-by-side reactor/regenerator con-figuration and a patented pre-acceleration zone to condition the regen-erated catalyst before feed injection. Modern Optimix feed distributors inject the feed into the riser, which terminates in a vortex separation system (VSS). A high efficiency stripper then separates the remaining hy-drocarbons from the catalyst, which is then reactivated in a combustor-style regenerator. With the RxCat process technology, a portion of the catalyst that has been stripped of residual hydrocarbon can be recycled back to the riser via a standpipe and the MxR chamber.
The reactor zone features a short-contact-time riser, state-of the art riser termination device for quick separation of catalyst and vapor, with high hydrocarbon containment (VSS/VDS technology) and RxCat tech-nology, wherein a portion of the stripped (carbonized) catalyst from the reactor is blended with the hot regenerated catalyst in a proprietary mix-ing chamber (MxR chamber) for delivery to the riser. Unlike other ap-proaches for increasing the catalyst-to-oil ratio, this technology does not affect the total heat balance and, therefore, does not increase coke yield.
Additionally, the recycling of cooler partially spent catalyst back to the base of the riser lowers the reactor inlet temperature which results in a reduction of undesirable thermally produced products, including dry gas.
The ability to vary the carbonized/regenerated catalyst ratio provides con-siderable flexibility to handle changes in feedstock quality and enables a real-time switch between gasoline, olefins or distillate operating modes.
Furthermore, because the catalyst delivered to the regenerator has a higher delta coke content relative to the base, non-RxCat operation, it requires less excess oxygen at a given temperature to sustain the same kinetic combustion rate. RxCat technology is operating in six units, with another eight installations current in design and/or construction phase.
The first unit to commercialize the RxCat process technology was suc-cessfully started up in 2005.
The combustor-style regenerator burns coke in a fast-fluidized envi-ronment completely to CO2 with very low levels of CO and limited pro-duction of NOx. The circulation of hot catalyst from the upper section to the combustor provides added control over the burn-zone temperature and kinetics. Catalyst coolers can be added to new and existing units to Continued
For heavier residue feeds, the two-stage regenerator is used. In the-first stage, the bulk of the carbon is burned from the catalyst, forming a mixture of CO and CO2. Catalyst is transferred to the second stage, where the remaining coke is burned in complete combustion, producing low levels of carbon on regenerated catalyst. A catalyst cooler is located between the stages. This configuration maximizes oxygen use, requires only one train of cyclones and one flue gas stream, which avoids costly multiple flue gas systems and creates a hydraulically-simple system to operate. The two stage regenerator system has processed feeds up to 8.5 wt% Conradson carbon.
UOP also offers two process technologies for maximizing propylene from feedstocks traditionally processed in FCC or RFCC units. The PetroF-CC and RxPro processes are specifically designed to meet increased propylene production requirements but are flexible to also operate in maximum gasoline mode, if required. Both processes utilize commercial-ly proven technology and mechanical features found in a conventional UOP FCC design, but are operated at process conditions that promote light olefin and/or aromatics production for petrochemical applications.
The commercially-proven PetroFCC technology provides a cost-effective means for producing moderate quantities of propylene from moderate quality feedstocks. The newest entry to the enhanced propylene plat-form at UOP, the RxPro process, employs a multi-stage reaction system with targeted olefin recracking to achieve a highest yield of propylene (> 20 wt%FF) for a given reaction severity and feedstock quality.
er regenerator temperature, higher catalyst circulation, lower dry gas make, increased conversion, and higher selectivity for desired products relative to conventional stripper designs. The AF packing option provide Installations: All of UOP’s technology and equipment are commercially proven for both process performance and mechanical reliability. UOP has been an active designer and licensor of FCC technology since the early 1940s and has licensed more than 250 FCC unit designs (including Resid FCC, MSCC, and PetroFCC process unit styles). More than 150 of these units are operating worldwide. In addition to applying our tech-nology and skills to new units, UOP is also extensively involved in the revamping of existing units.
Licensor: UOP, A Honeywell Company contact
Processes Index comPany Index Home
HYDROCARBON PROCESSING
®2011 refining Processes Handbook
Copyright © 2011 Gulf Publishing Company. All rights reserved.