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Crude Oil
Crude oil comprises crude oil, natural gas liquids, refinery feedstocks, and additives as well as other hydrocarbons (including emulsified oils, synthetic crude oil, mineral oils extracted from bituminous minerals such as oil shale, bituminous sand, etc., and oils from coal liquefaction). Crude oil is a mineral oil consisting of a mixture of hydrocarbons of natural origin and associated impurities, such as sulphur. It exists in the liquid phase under normal surface temperatures and pressure and its physical characteristics (density, viscosity, etc.) are highly variable. It includes field or lease condensates (separator liquids) which are recovered from associated and non-associated gas where it is commingled with the commercial crude oil stream. For more information on a specific product, please see the following list:
Additives
Additives are non-hydrocarbon substances added or blended with a product to modify its properties, for example, to improve its combustion characteristics. Alcohols and ethers (MTBE, methyl tertiary-butyl ether) and chemical alloys such as tetraethyl lead are included here. However, ethanol is not included here, but under liquid biofuels.
Natural gas liquids (NGL)
NGLs are the liquid or liquefied hydrocarbons produced
in the manufacture, purification and stabilisation of natural
gas.
These are those portions of natural gas which are recovered as liquids
in separators, field facilities, or gas processing plants. NGLs
include but are not limited to ethane, propane, butane, pentane,
natural gasoline and condensate.
Other hydrocarbons
Other hydrocarbons includes emulsified oils (e.g. orimulsion), synthetic crude oil, mineral oils extracted from bituminous minerals such as oil shale, bituminous sand, etc. and liquids from coal liquefaction.
Refinery feedstocks
A refinery feedstock is processed oil destined for further processing (e.g. straight run fuel oil or vacuum gas oil) other than blending in the refining industry. It is transformed into one or more components and/or finished products. This definition covers those finished products imported for refinery intake and those returned from the petrochemical industry to the refining industry.