öljyhiekkoihin

Öljyhiekka, sometimes referred to as tar sands, is a naturally occurring sedimentary rock deposit containing sand, clay, water, and a heavy, viscous form of petroleum called bitumen. Bitumen is too thick to flow freely at ambient temperatures, requiring specialized extraction methods compared to conventional crude oil. The largest known reserves of oil sands are located in Canada, primarily in the province of Alberta, but deposits also exist in Venezuela and Russia.

The extraction of bitumen from oil sands is a complex and energy-intensive process. Two main methods are employed: surface mining and in-situ recovery. Surface mining is used when the oil sands are close to the surface. In this method, the sand is dug up, transported to a processing plant, and then mixed with hot water and chemicals to separate the bitumen from the sand and water. In-situ recovery is used for deeper deposits and typically involves injecting steam into the ground to heat the bitumen, reducing its viscosity and allowing it to be pumped to the surface along with the injected water and any mobilized sand.

The resulting bitumen is then either upgraded into synthetic crude oil at the extraction site or diluted with lighter hydrocarbons to be transported via pipelines to refineries. The processing of oil sands has significant environmental considerations, including land disturbance from mining, water usage, greenhouse gas emissions, and the potential for habitat fragmentation. These factors have led to ongoing debate and research into more sustainable extraction and processing techniques.