Impacts of refining Canadian partially upgraded bitumen: Fluid catalytic cracking

Abstract

In this study, we examine the fluid catalytic cracking (FCC) performance of vacuum gas oil (VGO) from partially upgraded bitumen (PUB), a novel refinery feedstock from Canadian bitumen. FCC experiments were conducted in a lab‐scale FCC unit with VGOs from two different PUBs prepared using thermal cracking and solvent deasphalting, along with VGOs from unprocessed bitumen and light crude oil as reference points. The effect of blending PUB into light crude oil was also included in the assessment. All the VGOs were hydrotreated to sulphur and nitrogen levels acceptable for FCC intake. The FCC experiments covered a wide range of catalyst‐to‐oil ratios (3–10 g/g) with temperature fixed at 480°C. The VGOs from PUB had lower FCC reactivity and gasoline selectivity than those from unprocessed bitumen and light crude oil owing to their elevated aromaticity. The reduction in FCC reactivity and gasoline selectivity was more pronounced for the VGO from the PUB produced under the more severe thermal cracking conditions. Moreover, its FCC gasoline product was the most aromatic one. The VGOs from PUB were also more prone towards coke and dry gas generation and yielded more light cycle oil. Blending VGO from PUB into the one from light crude oil made FCC reactivity and gasoline selectivity shrink, yielding more coke, dry gas, and light cycle oil and making the gasoline product more aromatic. Overall, the findings indicate that the refining of VGOs derived from PUB in the FCC process is more challenging, primarily due to their high aromaticity.