Refinery how does it work

Crude oil is unrefined liquid petroleum. Crude oil is composed of thousands of different chemical compounds called hydrocarbons, all with different boiling points. Science — combined with an infrastructure of pipelines, refineries, and transportation systems - enables crude oil to be transformed into useful and affordable products.

Refining turns crude oil into usable products. Petroleum refining separates crude oil into components used for a variety of purposes. The crude petroleum is heated and the hot gases are passed into the bottom of a distillation column.

As the gases move up the height of the column, the gases cool below their boiling point and condense into a liquid. The liquids are then drawn off the distilling column at specific heights to obtain fuels like gasoline, jet fuel and diesel fuel.

The liquids are processed further to make more gasoline or other finished products. Energy Primers What is Fracking? Why is fracking for natural gas important? What Chemicals are Used in Fracking? Is that True? Does Hydraulic Fracturing Cause Earthquakes? What are Fracking Myths? Energy Tomorrow Blog. Distilling exploits the characteristic of the chemicals in crude oil to boil at different temperatures, a phenomenon that engineers chart along distillation curves.

Unlike a still, a distilling column contains a set of trays that allow heated vapors to rise and collect at different levels, separating out the various liquids derived from crude oil. The top of the column is cooler than the bottom, so as liquids vaporize and rise, they condense again, collecting onto their respective trays.

Butane and other light products rise to the top of the column, while straight-run gasoline, naphtha, kerosene, diesel, and heavy gas oil gather on the trays, leaving straight run residue at the base of the column. Because there is more demand for some distilled products like gasoline, refiners have an incentive to convert heavy liquids into lighter liquids.

The term cracking comes from the process of breaking up long hydrocarbon molecules into smaller, more useful molecules. The cracking process converts heavy straight run liquids into gasoline. There are multiple versions of the cracking process, and refiners use the process extensively.

Cracking is a highly controlled process, so cracking units exist separate from distillation columns. The process of reforming was developed to raise both the quality and volume of gasoline produced by refiners. Using a catalyst again, after a series of reforming processes, substances are converted into aromatics and isomers, which have much higher octane numbers than the paraffins and napthenes produced by other refinery processes.

Most simply, reforming rearranges the naphtha hydrocarbons to create gasoline molecules.