Fluid Catalytic Cracking (FCC) is the most important material conversion process in the oil processing industry and is used by some 400 refineries worldwide. In particular, heavy residues from vacuum distillation are processed and brought into contact with fluidised, solid catalyst material. There are different designs, but as a rule the plant consists of two fluidised bed reactors. In addition to the actual cracker, which is often designed as a riser reactor, the catalyst used must be treated and conditioned in a second reactor, the so-called regenerator (see figure).
Main products of the FCC process are naphtha fractions, which are mainly used for the production of gasoline and other fuels. In addition, gaseous products are formed from which liquefied petroleum gas (LPG) is recovered after separation of unsaturated hydrocarbons.