Abstract
An overview of several refinery process options that convert high boiling point fractions of crude oil into more valuable distillates is presented. The combination of Residuum Desulfurization (RDS) with Residuum Fluid Catalyst Cracking (RFCC) produces high yields of transportation fuels and chemicals feedstock with minimal fuel oil by-product. This process scheme can present formidable technical challenges for the catalysts of each process to handle the increased levels of contaminants such as Microcarbon Residue (MCR), nickel and vanadium present in heavy oil. This paper presents the results of hydrotreating heavier Atmospheric Residuums (AR) in RDS pilot plants with Ni-Mo supported catalysts. RDS pilot plant life tests are conducted and middle of run products are collected and distilled for analysis and further RFCC testing. Process condition variation and new catalyst development has been applied to improve RDS capability to handle heavier, more contaminated residuum. The RDS products are tested for RFCC reactivity using Advanced Cracking Evaluation (ACE) tests. The development of improved RFCC catalyst is applied to boost cracking catalyst tolerance of residuum metal contaminants. Judicious selection of newly developed RDS and RFCC catalysts enable production of higher yields of gasoline from heavier AR's. The coordinated application of new RDS and RFCC catalysts enables the conversion of dirtier residuum feedstock to produce greater yields of distillates.
