Because the new process requires less energy, it should also be cheaper. Smith adds that the equipment needed for heating and reusing the propane is less expensive than technology for managing the large volumes of water used in the steam process. 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, close to what it was in the 1990s and early 2000s (in inflation-adjusted dollars). N-Solv says the lower costs will make it possible to economically extract more than twice as much oil from the oil sands compared to conventional technologies.
The idea of using solvents to get at oil sands was proposed in the 1970s, but early experiments showed that the process couldn’t produce oil quickly enough. Two things changed that, according to N-Solv. First, horizontal drilling technologies now make it possible to run a solvent injection well along the length of an oil sands deposit, increasing the area in contact with the solvent, thus increasing production. Second, N-Solv determined that even small amounts of methane—a by-product of using a solvent—could contaminate the propane and degrade its performance. So N-Solv introduced purification equipment to separate methane from the propane before it is reused. The separated methane can also be used to heat the propane, further reducing energy costs.
Although N-Solv’s technology could reduce carbon-dioxide emissions from production, most of the emissions associated with oil sands—as with any source of oil—come not from producing the oil, but from burning it in vehicles and furnaces. The technology’s impact on climate change will depend on whether the process leads to increased oil production—if it does, it may actually result in increased net greenhouse-gas emissions, says David Keith, a chemical and petroleum engineering professor at the University of Calgary.
So far, the process has been tested only in a lab. Now N-Solv will begin a pilot project that could produce 500 barrels of oil a day. The $60 million project, which is mostly funded by private sources, will determine whether the process can work on a larger scale.