öljyhiekan

Öljyhiekka, also known as tar sands or oil sands, is a type of unconventional petroleum deposit. It is a naturally occurring mixture of sand, clay, water, and bitumen, a heavy, viscous form of petroleum. Bitumen is so thick that it will not flow unless heated or diluted with lighter hydrocarbons.

The largest known reserves of oil sands are located in Alberta, Canada, and in Venezuela. Extracting bitumen from oil sands is a complex and energy-intensive process. Two primary methods are used: surface mining for deposits close to the surface, and in-situ techniques, such as steam-assisted gravity drainage (SAGD), for deeper deposits. Surface mining involves excavating the oil sands and then separating the bitumen using hot water and chemicals. In-situ methods involve injecting steam into the reservoir to heat the bitumen and reduce its viscosity, allowing it to be pumped to the surface.

Once extracted and separated, the bitumen is upgraded into synthetic crude oil, which can then be refined into fuels and other petroleum products. The extraction and processing of oil sands have significant environmental implications, including land disturbance, water usage, greenhouse gas emissions, and potential impacts on ecosystems. These concerns have led to ongoing debates and research into more sustainable extraction methods and mitigation strategies.