Using steam extraction for the oilsands means that nine-tenths of the land above a reservoir can be left intact. There is no need for waste ponds because the sand is left underground and most of the water recovered from the bitumen can be cleaned with distillation for reuse. Steam can also produce bitumen from a reservoir half-a-kilometre underground, whereas strip mining is only economical for deposits less than 70 metres or so from the surface.
The proportion of bitumen produced with steam now stands at 53% and will continue to grow in Canada’s oilsands.
The Alberta Energy Regulator (AER) estimates the total bitumen resource-in-place in Alberta to be approximately 1.8 trillion barrels (which would be greater than all of the world’s known conventional reserves). Of this amount, 315 billion barrels are considered potentially recoverable using future technologies and economic conditions, and of that amount, 167.9 billion barrels are considered to be established or proved reserves that can be recovered using current, known technology.
Of the estimated 1.8 trillion barrels of total bitumen resource-in-place, roughly 536 billion barrels are attributed to carbonate formations. At 406 billion barrels, the Grosmont Formation is by far the largest carbonate reservoir in Alberta
Steam-assisted gravity drainage (SAGD), has proved particularly effective, says Ken Schuldhaus of the AER. SAGD involves drilling two horizontal wells through an oil-sands reservoir, one about five metres below the other. Steam is then released from the top well and over a few weeks can melt bitumen as far as 50 metres above and to the sides of the bore. The bitumen then percolates down and into the lower well, from which it is pumped to the surface.
In a trial last year, Suncor, an Alberta firm, found that adding oil-based solvents to steam increases recovery while reducing the amount of water that has to be heated by 15%. Suncor will begin commercial production within a year using solvents that include butane, propane and a proprietary substance that weakens the surface tension between liquids and solids.
Another Alberta firm, Laricina Energy, reckons it can cut the amount of water that needs to be heated by 25% or more. Such reductions promise to reduce break-even costs.
Laricina Energy solvent with SAGD test
The 1,800 barrel-per-day capacity Laricina Energy Saleski pilot consists of a central processing facility (CPF) with diluent treating and an adjacent well pad. The CPF consists of two 50MM BTU steam generators, associated water treating train, and a solvent injection / recovery system.
The Germain Commercial Demonstra on Project (CDP) is an in situ oil sands project. The CDP is Laricina Energy Ltd.’s first full-scale commercial development in the Grand Rapids Forma on, located in the western Athabasca region of northern Alberta. Laricina will use steam-assisted gravity drainage (SAGD) and incorporate solvent opera ons into its recovery process referred to as solvent-cyclic SAGD (SC-SAGD). The use of solvents is expected to reduce the amount of steam needed and as a result, reduce carbon emission intensity. Surface water is not used to create steam.
Imperial Oil, based in Calgary, has replaced steam altogether by injecting solvents under high pressure but at much lower temperatures. This will undergo a $100 million test this year.
This year Suncor began building facilities in Alberta to test melting bitumen with microwaves. It will insert a microwave-transmitting antenna into a horizontal borehole with the circumference of an arm but the length of a football pitch. The idea is to melt bitumen without wasting energy heating sand and rock—just as domestic microwave ovens heat moist food but not its glass or ceramic container. Laboratory tests suggest this could slash energy costs by 80%.
Nsolv has the potential for the following :
* Extraction Rate: ≥ SAGD extraction rates at 40°C with zero water usage
* Oil Quality:
Upgrade in-situ bitumen from ~8 °API to ~13 °API
* Nickel and vanadium less than 150 ppm
* Carbon residue at ~5%
* Recovery Factor: 65% or higher
* Solvent / Oil Ratio: 5 or less
* Solvent Hold-up: 0.2 bbl/bbl extracted or less
* GHG Emissions: Reduction of ≥ 80% relative to SAGD
Germany’s Siemens is developing a system that floods a thick copper cable with an electrical current to create an alternating magnetic field to melt bitumen. Tests could begin in a few years.