N-Solv Corporation holds patents for proprietary technology for in situ solvent extraction of bitumen from oil sands. The process uses no water and 85% less energy than Steam Assisted Gravity Drainage (SAGD). They have been awarded with $10.5 million by the Canadian government.
UPDATE – Technology Review has coverage
With conventional techniques, oil prices have to be above $50 to $60 per barrel—as they have been for several years—for oil sands to be economical. Smith says that with the solvent process, oil sands are still economical even if oil is $30 to $40 per barrel.
The N-Solv process is also expected to have lower operating and capital costs than SAGD with fewer restrictions on the reservoir conditions under which it can operate.
Other members of the consortium are oil sands producer Suncor Energy Inc. and Hatch Ltd.
In making the award, SDTC noted that Canada has some 170 billion barrels of recoverable crude oil stored in the oil sands. Of these remaining established reserves in Alberta, 80% are too deep to be mined and are currently recovered using in situ processes such as SAGD which is water- and energy- intensive.
N-Solv injects heated solvent (such as propane) vapor at moderate pressures into the gravity drainage chamber. The vapor flows from the injection well to the colder perimeter of the chamber where it condenses, delivering heat and fresh solvent directly to the bitumen extraction interface.
In solvent extraction, the production rate is limited by the rate that the solvent diffuses into the bitumen; the penetration rate of solvent into bitumen is determined by the bitumen viscosity. With Athabasca bitumen, a 25-30ºC temperature rise typically reduces the bitumen viscosity by a factor of 100. Thus, says N-Solv, a substantial acceleration in the bitumen extraction rate is achieved with a very modest increase in temperature. This is the key principle of N-Solv.