Abstract: The LTAG technology was adopted in the VGO hydrotreating and catalytic cracking units of Fujian Refining and Petrochemical Company to produce high octane gasoline using LCO and VGO. LCO and VGO were mixed and hydrotreated firstly. After separation, hydrotreated LCO and hydrotreated VGO were fed at different positions in the lower part of the riser reactor, respectively. The results showed that compared with the conventional method of feeding mixed hydrotreated LCO and wax oil, the catalytic cracking apparent conversion rate of hydrotreated LCO was increased by 5.17 percentage points, apparent cracking rate was increased by 7.87 percentage points, and the apparent condensation rate was decreased by 2.01 percentage points; the contents of olefins and aromatics in gasoline were increased by 1.2 percentage points and 2.0 percentage points, respectively; the gasoline octane number, RON and MON, were increased by 1.4 units and 0.8 units, respectively, showing that LTAG technology is effective method to convert LCO into high octane number gasoline.

Key words: catalytic cracking, LCO, gasoline, octane number