Since the 1920s, open pit mining has been central to oil sands development. But about 80% of the oil sands in Alberta are buried too deep for open pit mining. The oil must be recovered by in situ techniques. Steam is injected into the deposit to heat the oil sand, lowering the bitumen’s viscosity. The hot bitumen migrates toward producing wells, bringing it to the surface, while the sand is left in place (hence the name, in situ, which is Latin for “in place”). This technology is expensive, however, and requires certain conditions like a nearby water source. But, in situ production already rivals open pit mining and may well replace it as the main source of bitumen production.
Dr. Karl Clark developed and patented a hot water extraction technique still used today to extract oil from the oil sands. Using hot water to separate oil from the oil sands – mixing oil sand with hot water to create a slurry. Today, hydrotransport pipelines are used to condition and transport the oil sand from the mine to the extraction plant, where the slurry is fed into a separation vessel where it separates into three layers – sand, water and bitumen. The bitumen is skimmed off the top and cleaned and processed. Secondary recoveries are made and return smaller quantities of bitumen that would otherwise flow back to the settling ponds.
Bitumen is a complex hydrocarbon made of a long chain of molecules. In order for it to be processed, the chain must be broken up and reorganized. The end product is synthetic crude oil, shipped by pipelines to refineries to be refined further into jet fuels, gasoline and other petroleum products needed in more and more quantities today throughout the world.