Give examples of important industrial reactors and their applications.

Key examples include: Ammonia synthesis reactor (high pressure, promoted iron catalyst, fixed bed with cold shot cooling), Steam reformer (high temperature, nickel catalyst, tubular reactor for hydrogen production), FCC regenerator-reactor (fluidized bed, zeolite catalyst, petroleum cracking), Ethylene cracker (thermal cracking, tubular furnace, no catalyst), Polymerization reactors (slurry, gas phase, or solution type for plastics), and Fermenters (stirred tanks, biological reactions for pharmaceuticals and biochemicals).