For oil export, different countries have different units of oil measurement. For example, our country usually uses tons to calculate, Japan's crude oil futures are calculated in kilograms, while the United States uses barrels to calculate.
Composition of petroleum
The main components of petroleum are: oiliness (which is its main component), colloid (a viscous semi-solid substance), asphaltene (dark brown or black brittle solid substance) and carbon. Petroleum is a kind of colored flammable liquid with special smell, which is mainly composed of hydrocarbons. Strictly speaking, oil is mainly composed of hydrocarbons composed of hydrogen and carbon. The chemicals that make up petroleum can be decomposed by distillation.
As processed products, petroleum includes kerosene, benzene, gasoline, paraffin and asphalt. Strictly speaking, oil is mainly composed of hydrocarbons composed of hydrogen and carbon. The four hydrocarbons with the smallest molecular weight are all gases.