Heat Of Cracking For Naphtha In FCC Units Risers

摘要

Experience in Fluidized Catalytic Cracking Units has shown that it is advantageous tointroduce a naphtha stream in the FCC riser to produce light olefins like ethylene andpropylene, high valuable petrochemical feedstocks. The reactions are mainly endothermic andthe products are fuel gas, LPG, cracked naphtha, medium to heavy oil fractions, and cokedeposited on the catalyst.To model this type of operation one needs to know the heat of reaction for the naphtha. Onepossible path is to combine operating data and analyses of the naphtha stream and productseither from a pilot plant or from an industrial unit. The analyses include ASTM D-2887distillation, density, PIANIO chromatography and heats of combustion of the naphtha feed,cracked naphtha, and other products. These data are combined with heats of reaction for thepure compounds and operating data in a computer routine which performs the heat balance.This work presents results of heats of reaction for the cracking of naphtha obtained in a FCCpilot plant of our Research Center.