The Fluid Catalytic Cracking Unit (FCCU) cracks heavy, low-value feedstocks into high-value, lighter molecular weight hydrocarbons which are blended to finished products. A cracker can produce a wide variety of yield patterns by operating in either Gasoline, Distillate or LPG modes.
Catalytic crackers utilize a reactor and a catalyst regenerator with connecting risers where the reactions take place. Level controllers are often positioned on the first stage regenerator and at the top of the reactor. Level measurements involve fluidized solids levels at high temperatures. Conventional measurement techniques can be subject to plugging.