Solvent Selection Criteria and Optimal Application Conditions for Heavy-Oil/Bitumen Recovery at Elevated Temperatures: A Review and Comparative Analysis

Abstract

Sole thermal or solvent methods for heavy-oil recovery are not effective enough to deliver cost efficient processes. Hybrid applications of those two techniques have been proposed to take advantage of each and a wide range of investigations have been recently performed focusing on extreme conditions such as bitumen containing sands and carbonates, deep reservoirs, and oil-wet fractured carbonates. What is critically important in these applications is to determine the best performing solvent for a particular application and optimal application conditions for a given solvent at high temperature conditions. In this study, the results from various reported works on the hybrid applications of thermal (mainly steam) and solvent methods were complied, analyzed, and compared. Attention was given to a comparative analysis of steam-over-solvent injection in fractured reservoirs (SOS-FR) method. Steam/solvent methods show a promising outcome in general, while specific modifications must be taken into account for different application situations. These were discussed and specified, especially from proper solvent type and optimal application conditions for alternate injection of steam and solvent in different reservoir types.

New insight to experimental study on pore structure of different type reservoirs during alkaline‐surfactant‐polymer flooding

“…In recent years, most of the oilfields have entered the middle and later stage with serious problems, including formation heterogeneity and low recovery factor 1–3 . As the demand for fossil and renewable energy continuously increases in the world, 4 crude oil plays a critical role in the maintenance of energy consumption nowadays 5,6 . The Global Energy Review 2021 predicts that global energy demand has grown by 4.6% in 2021.…”

“…[1][2][3] As the demand for fossil and renewable energy continuously increases in the world, 4 crude oil plays a critical role in the maintenance of energy consumption nowadays. 5,6 The Global Energy Review 2021 predicts that global energy demand has grown by 4.6% in 2021. Global oil demand is expected to increase by 5.4 million barrels a day from the same period last year, up 6% from a year earlier.…”

Selection of Optimal Solvent Type for High-Temperature Solvent Applications in Heavy-Oil and Bitumen Recovery

“…As a result of the high cost of the solvents, its industrial applications require a better understanding of solvent performance through extensive laboratory and computational efforts to optimize its use by minimizing its cost through maximized retrieval − and maximized oil recovery. − In this optimization process, the primary task is to select the proper solvent for given application conditions (temperature and injected amount), reservoir type, and oil composition. − …”