A novel high-severity FCC process for enhancing the production of light olefins

The conventional FCC is being extended, using technology developed in Japan and Saudi Arabia, to a high-severity FCC (HS-FCC) to produce significantly more olefins and high-octane gasoline. The operating regime of this novel process is more severe than that of a FCC, and utilizes a special down-flow reaction system. The HS-FCC process allows high catalyst/oil ratio and prevents back-mixing that yields undesirable by-products. The cracking of VGO was studied in detail using a commercial equilibrated FCC catalyst in a 0.1 bpd circulating downer pilot plant. The significant enhancement in the yield of light olefins, mainly propylene, as well as an improvement in gasoline quality was also discussed. Based on the success of pilot plant testing, a 30 bpd HS-FCC demonstration plant is being designed and constructed of a local refinery in Saudi Arabia. The advantages of HS-FCC process for an integrated refinery-petrochemical complex, i.e., enhancement of propylene and isobutylene production, maintaining gasoline yield at high conversion, and suppressing dry gas formation at high cracking temperatures as well as high flexibility for feed oil were discussed.