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Oil refinery

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An oil refinery is a massive industrial complex designed to transform crude oil into useful products.

Refinery, Bayport Industrial Complex, Harris County, Texas
Refinery, Bayport Industrial Complex, Harris County, Texas

Crude oil, or petroleum, is a raw feedstock that is generally not useful in its natural state. It consists of hundreds of different hydrocarbon molecules. These molecules are composed of hydrogen and carbon atoms. Because these molecules vary in mass and structure, they possess different physical and chemical properties. Refineries separate these components to create fuels, lubricants, and feedstocks for the petrochemical industry. This process is a vital part of the petroleum industry's downstream sector.

Usesofpetroleum
Usesofpetroleum

The primary mechanism used in refining is distillation.

Crude Oil Distillation-en
Crude Oil Distillation-en

This process relies on the fact that different hydrocarbons have different boiling points. Inside a refinery, extensive piping carries fluid streams to large chemical processing units. One central unit is the distillation column. In these columns, heat is applied to separate the oil into different fractions. Lighter liquid products, which are in high demand for internal combustion engines, rise to different levels than heavier components. Some refineries also use a process called cracking. Cracking breaks heavy hydrocarbons into lighter, higher-value products like gasoline.

RefineryFlow
RefineryFlow

Other units, such as vacuum distillation or visbreakers, help manage the viscosity and weight of the oil.

Refine
Refine

Refineries produce a wide variety of distinct products. These include gasoline, also known as petrol, and diesel fuel. They also create kerosene, which can be seen as a clear liquid in a jar.

Kerosene in mason jar
Kerosene in mason jar

Other products include liquefied petroleum gas (LPG), petroleum naphtha, and heating oil. Heavier components are turned into asphalt base for roads.

Asphalt Concrete
Asphalt Concrete

Beyond fuels, refineries produce petrochemical feedstocks like ethylene and propylene. These feedstocks are essential for manufacturing plastics, detergents, solvents, and synthetic fibers like nylon or polyester.

LPG cylinders
LPG cylinders

The history of oil refining stretches back to ancient civilizations. The Chinese were among the first to refine oil for energy as early as the first century. Between 512 and 518, the writer Li Daoyuan described refining oil into various lubricants.

Рафинерија нафте Брод (Oil refinery Brod, Republika Srpska)
Рафинерија нафте Брод (Oil refinery Brod, Republika Srpska)

Persian chemists also used distillation, and by the 9th century, oil fields were being exploited near modern Baku, Azerbaijan. In China, the Northern Song dynasty even established the "Fierce Oil Workshop" to produce oil-powered weapons. The modern era of the industry began in the mid-1800s. Abraham Gessner produced kerosene from coal in 1846, and Ignacy Łukasiewicz produced kerosene from oil wells in Poland in 1854.

Motor oil
Motor oil

Technological advancements significantly increased refining efficiency during the 20th century. In 1908, the Romanian chemist Lazăr Edeleanu invented the Edeleanu process. This was a modern method of liquid extraction for refining crude oil. It allowed for much greater efficiency than pure fractional distillation alone. This process eventually spread to France, Germany, and the United States. In the United States, the industry changed rapidly with the invention of the internal combustion engine. While early refineries focused on kerosene for lamps, the rise of automobiles created a massive demand for gasoline. This shift drove the rapid growth of refinery size and complexity worldwide.

Refineries vary greatly in scale and capacity. In 2020, the total global capacity for crude oil refining was approximately 101.2 million barrels per day. The Jamnagar Refinery in Gujarat, India, has been the world's largest refinery since December 2008.

Jamnagar Refinery
Jamnagar Refinery

Owned by Reliance Industries, it has a processing capacity of 1.24 million barrels per day. In the United States, the industry has seen changes in how refineries operate. While the number of refineries has decreased due to mergers and closures, the total capacity has remained relatively stable. For example, in 1982, the U.S. operated 301 refineries with a capacity of 17.9 million barrels per day. By 2014, the number of U.S. refineries dropped to 140, but the capacity actually increased to 18.02 million barrels per day.

Modern refining is also shaped by environmental and economic factors. In the United States, new refinery construction has been very difficult due to strict air and water cleanliness standards. Instead of building new plants, many companies revamp existing units. They do this to increase octane ratings in gasoline or to lower the sulfur content in diesel. This helps them comply with environmental regulations regarding air and water pollution. Refining is a complex balance of chemistry, engineering, and economics. It connects the raw resources extracted from the earth to the many products that power modern life and industry.

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🖼️ Images & Media (25)
File:RefineryFlow.svg
RefineryFlow.svg
File:Refine.svg
Refine.svg
File:Crude Oil Distillation-en.svg
Crude Oil Distillation-en.svg
File:Рафинерија нафте Брод (Oil rafinery Brod, Republika Srpska).jpg
Рафинерија нафте Брод (Oil rafinery Brod,...
File:Рафинерија нафте Брод (Oil refinery Brod, Republika Srpska).jpg
Рафинерија нафте Брод (Oil refinery Brod,...
File:Refinery of Slovnaft, view from Nový most viewpoint in Bratislava, Bratislava II District.jpg
Refinery of Slovnaft, view from Nový most...
File:Refinery, Bayport Industrial Complex, Harris County, Texas.jpg
Refinery, Bayport Industrial Complex,...
File:Haifa Refinery by David Shankbone.jpg
Haifa Refinery by David Shankbone.jpg
File:Bidboland gas refinery.jpg
Bidboland gas refinery.jpg
File:ExxonMobil Baton Rouge.jpg
ExxonMobil Baton Rouge.jpg
File:Anacortes Refinery 31911.JPG
Anacortes Refinery 31911.JPG
File:Anacortes Refinery 32017.JPG
Anacortes Refinery 32017.JPG

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