Industrial: Refining: Fluidized Catalytic Cracking

Fluid Catalytic Cracking Units (FCCUs) are a secondary conversion operation within more complex refineries, and is used to produce additional gasoline, primarily, from the gas oils produced in the atmospheric and vacuum distillation units.

Fluid catalytic cracking is a chemical process that utilizes a catalyst and heat to break long-chain hydrocarbons into smaller-chain hydrocarbons. Typical products include gasoline, distillate, butane, and propane fuels. The catalyst is a sand-like solid material that is fluidized by the hot liquid and vapor fed into the FCCU. The catalyst can flow between the reactor and regenerator vessels in the FCCU due to this fluidity.

Once the gas oils are cracked by the catalyst and heat, the resultant effluent stream is sent to a fractionator that separates the effluents based on boiling points into several products, including gasoline, light and heavy gas oils, slurry oil, and butane and lighter hydrocarbons.

FCC gasoline must be desulfurized and also reformed before it can be sent to blending for the finished gasoline product. Light gas oil is also desulfurized before it is blended into finished diesel or heating oil. Heavy gas oil is sent to a coker or hydrocracker for further processing. Slurry oil can be sent to a coker for further processing, or blending into residual fuel oil. Fractionator overhead gases are processed into fuel gas (methane and ethane), propane, propylene, butane, and butane (for sale or further processing).

Carbon, referred to as catalyst coke, is deposited on the catalyst during the cracking process, and reduces the catalyst’s capacity to crack the gas oils. The coke is burned off the spent catalyst in the Regenerator, which also reheats the catalyst to the temperatures required for the reactor. Flue gas produced in the Regenerator exits the vessel overhead and is routed to environmental control equipment and then discharged to the atmosphere.


catalytic cracking2

MEI Maverick Engineering, a wholly owned subsidiary of Triple 5 Worldwide, can be of assistance with your FCCU projects, and can work closely with whichever Licensor you select. MEI can provide the complete range of services, including front-end engineering design, detail engineering, procurement, construction management, start-up and operator training, to insure a successful project. Our expertise yields shorter project schedules, industry superior cost control, and minimal client risk.

Fluidized Catalytic Cracking: Projects

  • Revamp for FCCU Cooler to increase steam production and reliability.
  • Upgrade for FCCU Radial Feed Injection, Feed/Slurry exchangers, Feed pumps, and instrumentation