Recent Advances in Nonaqueous Extraction of Bitumen from Mineable Oil Sands: A Review

Abstract

Investigations of nonaqueous extraction (NAE) of bitumen from minable oil sands have been extensively revisited in the past decade as an alternative to Clark hot water extraction (CHWE). Significant advances have been achieved in understanding NAE processes at bench and pilot scales, although many questions remain regarding the commercialization of NAE. This critical review summarizes recent research findings and progress on fundamental and practical aspects associated with novel extraction processes, focusing on the technological method, solvent selection, recovery of solvent, and removal of fines. The review also identifies opportunities and challenges for bitumen recovery from oil sands using nonaqueous processes.

Impact of a novel bitumen extraction process on mined oil sands tailings behavior

“…It should be pointed out that the choice in different temperatures between standard WBE and the novel HBE processes was purely attributed to the essential operation criteria required for each process. Commercial WBE process should be operated at higher temperatures which have been reduced from the original 80°C to the current 50°C, but further reductions in extraction temperature for a WBE‐based process have proved unfeasible and would produce unsatisfactory recovery rate and quality . Heating water to higher temperature in the WBE process requires large energy consumption and creates high GHG emission concerns.…”

“…Oil sand tailings are an aqueous, alkaline, muddy suspension of waste underflows produced when recovering bitumen from oil sands ores using Clark hot water extraction (CHWE) or its commercial variants . Tailings containing water, coarse sands, fine clays, unrecovered bitumen, soluble organics, and inorganic salts are discharged to and stored in ponds . In a storage pond, whole tailings undergo segregation in which the sand particles settle rapidly to form beaches (with some fines capture), whereas the remaining aqueous slurry containing fines and residual hydrocarbons, runs off into the pond.…”

Challenges in developing polymer flocculants to improve bitumen quality in non-aqueous extraction processes: an experimental study

“…Of particular interest are non-aqueous bitumen extraction processes based on organic solvents intended to Edited by Xiu-Qiu Peng Electronic supplementary material The online version of this article (https ://doi.org/10.1007/s1218 2-019-00414 -z) contains supplementary material, which is available to authorized users. eliminate water use and long-term tailings storage (Lin et al 2017). Non-aqueous extraction processes, however, face challenges in solvent recovery and solids migration to the bitumen product (Lin et al 2017).…”

“…eliminate water use and long-term tailings storage (Lin et al 2017). Non-aqueous extraction processes, however, face challenges in solvent recovery and solids migration to the bitumen product (Lin et al 2017). Process aids, such as polymers, are one approach that may improve the efficiency of non-aqueous bitumen extraction processes (Lin et al 2017).…”

“…Both commercial extraction processes and pilot-scale non-aqueous extraction processes currently require an additional solids removal step before the bitumen product can be transported by pipeline (Rao and Liu 2013;Lin et al 2017). The use of polymers as flocculants in organic media and in oil applications, have been, to the authors' knowledge, largely underexplored as a means of flocculating solids in these media, with previous studies being restricted to model systems (Ngnie et al 2018).…”