VAPEX and Solvent Technology
VAPEX and cold solvent technologies don’t use steam as the primary method of softening the bitumen underground. Instead, various combinations of solvents are injected into the ground using injection wells and equipment similar to SAGD.
Vaporized hydrocarbon solvents are injected into the reservoir, reducing the viscosity of bitumen by “dissolving” it in the solvent rather than by heating it and thereby causing it to drain into a horizontal production well.
Cold solvent technology is a non-thermal in-situ production method that results in as much as 85 per cent fewer GHG emissions than thermal processes; however, it also takes considerably longer to produce the oil.
Solvent-steam technology uses solvents along with steam to increase the efficiency of steam-assisted oil sands production while still minimizing environmental impacts.
Laricina Energy Ltd. has explored the possibility of using solvents with steam in different geologic formations using Genetic Algorithms software, a computer program that mimics the genetic process in order to find the best possible solvent-steam recipe for getting the most oil out of a reservoir.
Using solvents instead of steam could mean reducing the operating steam-to-oil (SOR)* ratios by 30 per cent, with the accompanying reduction in GHG emissions.
*Note: SOR is the volume of steam required to produce one unit volume of oil. The lower the SOR, the more efficiently the steam is utilized and the lower the associated fuel costs.
To date, solvent use is still in the development stage and is not yet commercially applicable.