API gravity: American Petroleum Institute gravity. A measure of how light or heavy an oil is, compared with water. If an oil has an API gravity greater than 10°, it will float on water. If its API gravity is less than 10°, it will sink. Bitumen has an API gravity of from 8° to 14°.
Asphaltenes: Large hydrocarbon molecules that are the heaviest fractions in bitumen. These are removed as bottoms from fractionating towers.
Barrel: In the oil business, one barrel equals 159 litres, or 42 US gallons.
Bitumen: A naturally occurring hydrocarbon that is so thick, it will not flow at room temperature. Bitumen extracted from Alberta’s oil sands typically has an API gravity of 8° to 14°.
Bituminous sands: Another name for oil sands. As “bituminous” describes a very broad group of substances, the term oil sands is preferred as being more specific.
Bottoms: The component of crude oil extracted from the bottom of a fractionating tower. When oil is processed in a fractionating tower, the components with the highest boiling points accumulate at the bottom of the column.
Catalyst: A substance that plays a role in a chemical reaction, but is not itself altered by the reaction.
Coke: The high carbon by-product of the coking process, which removes carbon from oil to create more valuable hydrocarbons.
Coking: The process of removing carbon from the heaviest fraction of bitumen by applying high temperature and pressure.
Conventional oil: Naturally occurring hydrocarbons in liquid form that are capable of being pumped without processing or dilution.
Cracking: A number of upgrading or refining processes that can be used to break or “crack” large hydrocarbon molecules into smaller, more useful and valuable hydrocarbon molecules.
Crude bitumen: See Bitumen.
Crude oil: Naturally occurring or synthetic combustible hydrocarbons that can be processed into petrochemicals such as gasoline, diesel, propane, etc.
Density: The ratio of mass to volume. The heavier a certain volume of something is, the denser it is said to be. A cubic centimetre of gold is heavier than a cubic centimetre of silver, so gold is more dense than silver. See API gravity.
Diluent: A light hydrocarbon substance, such as naphtha, that can be used to dilute crude bitumen so that it can be transported by pipeline.
Distillation: The process by which the parts, or fractions, of crude oil are isolated from each other, without any change being made to their individual chemical structure. This is achieved using a heating unit and a fractionating tower.
Extraction: Separating the oil sands to access the bitumen.
Fines: Tiny solid particles of materials such as clay, sand or silt. Fines must be removed from the oil sands in order for the oil to be usable.
Fraction: One of several types of hydrocarbons present in crude oil that can be separated from each other by distillation. For example, naphtha is a very light fraction, while asphaltenes are very heavy.
Fractionating tower: A tool for separating the various fractions found in crude oil. Heated oil is piped into the bottom of a tall metal column, and the most volatile fractions—those with the lowest boiling point—rise to the top. Those fractions that boil at higher temperatures do not rise as high within the column. Different types of hydrocarbons can be extracted from the fractionating tower at different heights. For example, naphtha is extracted at the top, while asphaltenes are extracted at the bottom.
Froth: A layer of bubbles that forms on top of a liquid when it is heated or agitated.
Heavy oil: Oil that has an API gravity of less than 20°. Heavy oil is harder to extract and more expensive to refine than light crude oil because it is dense and viscous.
Hydrocarbon: Naturally occurring organic compounds that contain only carbon and hydrogen.
Hydrocracking: A process for reducing heavy hydrocarbons into lighter fractions, by using high temperatures, high pressure, and a catalyst to break up and add hydrogen to the large molecules.
Hydrotreating: A process that removes impurities such as sulfur and nitrogen from hydrocarbons, using relatively low temperatures and hydrogen.
In situ: Latin for “in place.” Methods for extracting bitumen from deposits too deep below the surface of the ground to mine are referred to as in situ.
Muskeg: A boggy type of soil found in the boreal forest. Muskeg can be up to three meters thick and is composed of decaying plants, peat, moss and water.
Naphtha: One of the most volatile and flammable fractions of crude oil. It is often used to dilute bitumen that is being upgraded.
Oil Sands: A naturally occurring mixture of sand, clay, silt, rocks, other minerals and bitumen. Also known as Tar Sands or Bituminous Sands.
Overburden: The rock, clay, sand, soil and muskeg that lies on top of an oil sands deposit, and is removed to allow it to be mined.
Pay thickness: The thickness of an oil sands deposit in the ground.
Petroleum: A naturally occurring liquid flammable hydrocarbon.
Pipe still: A heater in which oil is pumped through a pipe that is coiled inside a firebox.
Pulp: Historically used synonymously with slurry.
Remediation: The resolution of potential environmental or health hazards at a site through the physical removal or neutralization of harmful substances.
Slurry: A thin mixture made up of a liquid and small solid particles.
Synthetic crude oil: The lighter fractions produced by upgrading bitumen from oil sands.
Tailings: The residue of sand, silt, fine clay particles, minerals and hydrocarbons after bitumen has been separated from oil sands.
Tar sands: Another name for oil sands. As tar is a man-made substance, this name has fallen into disuse as being inaccurate.
Upgrader: A plant where bitumen is subjected to processing that frees up lighter fractions—synthetic crude oil—that can be further refined into valuable products.
Upgrading: The conversion of bitumen into synthetic crude oil by removing carbon (coking) or adding hydrogen (hydrocracking), and removing impurities such as sulfur and nitrogen (hydrotreating).
Viscosity: A description of how easily a liquid will flow. Internal friction between the molecules in a liquid causes it to resist changing its shape. The more complex the molecules, the greater the resistance and the higher the viscosity of the liquid.