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In this study, we investigate a process for partial upgrading of Canadian oil sands bitumen by means of modelling and simulation. In continuation of our previous study focused on a different process configuration for partial upgrading, the process scheme analyzed in this work consists of a solvent deasphalting step to reject asphaltenes from bitumen, a thermal cracking of the deasphalted product step, and a hydrotreating step to saturate the olefins generated by thermal cracking. The model was built using commercial simulation software, incorporating customized models for the solvent deasphalting and thermal cracking units. Trends in partial upgrader product yields and quality are examined under two operating scenarios: one where the thermal cracker operates in once‐through mode and the other where the heavy portion of the thermal cracker product is recycled. Both scenarios were observed to have difficulties in achieving the product quality targets set for partial upgrading (density <0.9400 g/cm3 at 15.6°C and viscosity <350 cSt at 7°C) without any diluent addition. A key factor that significantly impacts final product yield and quality in this partial upgrading process is the formation of new asphaltenes during thermal cracking. [ABSTRACT FROM AUTHOR]

Partial upgrading is an emerging direction in the processing of Canadian oil sands bitumen in response to the economic and environmental challenges in the oil sands industry. Partial upgrading aims to improve bitumen quality only to the level at which pipeline specifications are met without use of diluent. Given that partial upgrading technologies have not yet reached commercial deployment, there is a lack of technical data to assess the expected benefits in terms of energy input and greenhouse gas emissions reduction. In this study, we present an assessment of a partial upgrading scheme using detailed process simulation. We developed a conceptual process scheme considering visbreaking, solvent deasphalting, and naphtha hydrotreating as the core partial upgrading processes. Reactor models were assembled using experimental data from CanmetENERGY's pilot plant facilities and from the literature and integrated into a plant‐wide simulation model. Simulations allowed the examination of trends in partial upgrader product yields and quality and enabled a comparison with traditional bitumen upgrading. [ABSTRACT FROM AUTHOR]

Dealing with vapor–liquidequilibrium (VLE) in hydrotreatingreactors is a major obstacle to realistic process simulation. Thepresent study focused on the modeling and simulation of a commerciallight-cycle-oil (LCO) hydrotreater with rigorous vapor–liquidequilibrium (VLE) calculations. The hydrotreater was represented asa one-dimensional plug-flow adiabatic reactor with interbed gas quenching.The model accounted for the hydrodesulfurization (HDS) and hydrodearomatization(HDA) reactions. VLE calculations were performed in situ with a calibratedflash calculation program developed in-house specifically for hydrogen–petroleumsystems. Significant differences in reactor temperature profiles,hydrotreating conversions, fluid rates, and phase compositions wereobserved between the simulations with and without VLE. Analysis ofthe effect of temperature indicated that reactor performance dependsheavily on the axial temperature distribution, which is establishedbased on the catalyst bed layout and the selection of bed inlet temperatures.It was observed that, although conversion levels were improved athigher inlet temperatures, there was an increase in quenching gasrequirement, vaporization rate, and the formation of high-temperaturezones toward the inlet of the reactor. In a similar manner, pressurewas found to increase hydrotreating performance markedly but withan extensive heat release. Verification of plug-flow and full-catalyst-wettingconditions during the simulations confirmed that all criteria weresatisfied in this study. [ABSTRACT FROM AUTHOR]