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arXiv · 2401.17715

Numerical insights from population balance model into the distribution of bitumen residues in industrial horizontal pipes during the hydrotransport of oil sands tailings

Abstract

Pipeline transportation is a vital method for conveying crushed oil sand ores and tailings in the oil sands industry. This study focuses on enhancing economic benefits by exploring the separation of valuable bitumen residues from coarse sand tailings within hydrotransport pipelines. Employing three-dimensional transient Eulerian-Eulerian computational fluid dynamics (CFD) simulations coupled with a population balance model (PBM), we examine the aggregation and breakage of bitumen droplets under various flow conditions. The CFD-PBM model's accuracy is validated against field measurements of velocity profiles and pressure drops. Our findings reveal that higher slurry velocities lead to intensified particle-bitumen interactions, resulting in reduced aggregated bitumen droplet sizes at the pipeline's core. Additionally, variations in bitumen fraction cause shifts in the distribution of coarse particles along the pipe's vertical axis, with increased aggregation and larger droplets in the upper region. Notably, we demonstrate that smaller bubbles promote a more uniform distribution of bitumen compared to larger bubbles. These insights provide valuable knowledge for optimizing bitumen recovery processes, facilitating the integration of pipeline dynamics with downstream separation and extraction units.

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Somasekhara Goud Sontti, Xuehua Zhang. 2024-01-31. Numerical insights from population balance model into the distribution of bitumen residues in industrial horizontal pipes during the hydrotransport of oil sands tailings. https://doi.org/10.1021/acs.iecr.3c03140

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