AM-02-08 FRACTIONATION IMPACT ON FCC GASOLINE AND LCO SULFUR CONTENT

Description:

New U. S. regulations requiring 30 ppm sulfur gasoline phase in beginning in 2004. In 2006 regulations requiring 15 ppm sulfur diesel take effect. The technology to achieve the required sulfur levels has focused primarily on improved hydrotreating technology, with a few novel processes being introduced and even commercialized. A combination of these technologies will form the backbone for the industry's approach to meeting these requirements. Very little has been written regarding the potential clean fuels benefits of improved refinery fractionation. Much of the data available in the public domain suggest that improved fractionation could have tremendous benefits. However, most of what has been written focuses on either splitting Fluid Catalytic Cracking (FCC) Unit naphtha to minimize hydrotreating requirements and olefin saturation or on under-cutting the naphtha to reduce the amount of sulfur that makes it into the gasoline pool. Both of these approaches neglect the potential of simply improving the existing splits between the FCC products while maintaining constant yields. Although the potential to reduce sulfur concentration through improved fractionation has been suggested,1 it has not been investigated in detail. Through laboratory analysis and simulation studies of a commercial FCC Main Fractionator this paper will attempt to highlight the potential value of improved product fractionation.