Heavy oil is a type of crude oil that is thicker, denser, and more viscous than conventional light crude oil. It has a higher molecular weight and contains a larger proportion of heavier hydrocarbons, making it more difficult and costly to extract, transport, and refine. Heavy oil typically has a higher density and lower API gravity (American Petroleum Institute gravity), which is a measure of how light or heavy a petroleum liquid is compared to water. A lower API gravity means the oil is denser and heavier.
Heavy oil is a significant energy resource, as it is abundant, especially in places where light crude reserves are declining. However, due to its challenges, production is often more expensive and has a larger environmental impact.
Key Points about Heavy Oil
High Viscosity - Heavy oil is much thicker than light oil, meaning it flows slowly. It often requires heating or dilution with lighter oils to move through
pipelines.
High Sulfur and Metal Content - Heavy oil usually contains more sulfur, heavy metals, and impurities than lighter oils, making refining more complex.
Lower API Gravity - Heavy oils typically have an API gravity of less than 20°, while light oils have a higher API, generally above 30°.
Thermal and Chemical Extraction Methods - Due to its high
viscosity, heavy oil often requires enhanced recovery methods like steam injection, solvents, or other thermal processes to reduce viscosity and improve flow during extraction.
Found in Specific Regions - Major heavy oil reserves are located in regions like Canada (particularly Alberta’s oil sands), Venezuela’s Orinoco Belt, and parts of the Middle East.
