Abstract: Long cycle operation of residue hydrotreating unit is beneficial to the utilization of catalysts and the profit of complex process of residue hydrotreating-catalytic cracking unit. In this paper, the influences of the feedstock properties on catalyst performance and operating cycle were discussed. The commercial results showed that a long and stable operation of the unit was acquired by the optimization of feedstock property and the application of RIPP’s RHT third generation catalysts.

Key words: residual oil, hydrofining, feedstock, fixed bed