Refining: From Crude Oil to Petroleum Products

Different types of crude oilOil that has not been refined. look different: some are black and viscous, others are brown and fluid. But none of them can be used as is in car engines, boilers or manufacturing units. They first have to be converted into various finished products through refining All industrial processes used to obtain various petroleum products, such as gas, gasoline, heating oil and asphalt, from crude oil. (See Close-Up: "Why Crude Oil Needs to be Refined").

Everyone is familiar with the names of most of these products: gasoline (called petrol in some countries) and dieselDiesel is the name of an internal combustion engine that works by compression-ignition... are fuels for cars and trucks; jet fuelFuel is any solid, liquid or gaseous substance or material that can be combined with an oxidant... powers aircraft; liquefied petroleum gas (LPG)Combination of light hydrocarbons produced partly from the refining of crude oil (about 40%) and partly from the processing of natural gas.. , also known as butane and propane, is an automotive fuel or is packaged in bottles and used for household needs; fuel oil is used in domestic and industrial boilers; base oils are used to produce lubricants; and asphaltAt ambient temperature, a sticky, black and highly viscous or solid mixture of heavy hydrocarbons... (or bitumen) is used to pave roads. There is also naphtha, which is the main feedstock for petrochemicals.

Refining Operations

Crude oil is converted into petroleum products in a number of steps in refineries (See Close-Up: "The Three Stages of Refining"). The first is atmospheric distillation at 350 to 400°C. The crude oil vapors rise inside the column, while the heaviest molecules remain at the bottom. The heavy residues are distilled again in another column.

After separation, the next step is conversion at a temperature of 500°C. Processes include catalytic cracking and hydrocrackingRefining process that converts heavy hydrocarbons into lighter, low-sulfur products in the presence of hydrogen. , which “crack” the molecules that are still too heavy, producing gas, gasoline and diesel. Then molecules that are corrosive or cause air pollution, such as sulfur, are removed.