What is oil refining? – Know all the stages of oil refining
have you ever wondered how is oil transformed in the products we use every day, for example, gasoline, diesel or plastic? Do you know what crude oil refining is and why it is so important for industries? In this article we will explain in a simple way what it consists of and how important is the chemical process that converts this black gold into a variety of useful substances for our society.
What is the definition of oil refining?
It is the process that consists of separating and transforming the components crude oil in order to obtain useful products for society, such as gasoline, diesel, asphalt, among others. It is carried out in facilities called ‘refineries’, where crude oil is subjected to different physical and chemical processes to obtain the desired fractions.
Crude oil is a complex mixture of hydrocarbons and other organic and inorganic compounds, which varies according to its origin, color, viscosity, sulfur content, and other properties. Therefore, refineries must adapt to the quality and quantity of crude they transform, as well as the market demand for derived products.
What is crude oil refining?
It is the process that consists of transform and purify petroleum compounds and thus obtain useful products for society, such as fuels, lubricants, plastics and other derivatives. However, a series of physical and chemical operations are needed to adapt the crude to the specifications and market demands.
As mentioned above, this process It is carried out in facilities called refineries., which can be simple or complex depending on the number and type of processing units they have. They are usually located near the sources of crude oil supply or the centers of consumption of refined products. This is done in order to reduce transportation costs.
This process can be divided into three stagesknown as:
One of the most advanced refining systems in the industry is that of the energy multinational Repsol SA, where they transform crude oil and various alternative raw materials in order to generate higher value products and lower carbon intensity.
What is the purpose of oil refining?
The purpose is to transform crude oil into commercial products that have a constant composition and propertiesthat can be used in a certain branch of industry, such as combustion engines.
To achieve this purpose, crude oil must undergo a series of alterations that include the fraction of this and the chemical transformations. These processes will always be carried out at the refinery, where the crude is treated to extract its commercial fractions.
Oil refining is based on the different physical and chemical properties of hydrocarbons that make up crude oil, such as boiling point, density, viscosity, sulfur content, and octane number. These properties determine the quality of the oil and the products that can be obtained from it.
What is obtained by refining oil?
Products with a greater commercial scope can be accessed by adapting them to the required technical specifications. Some of the chemical transformation processes to obtain these products are the following:
- cracking. It breaks the heavier and more complex hydrocarbon molecules and converts them into lighter and simpler ones. This is accomplished by heat, pressure, or catalysts. In this way they are obtained products like gasolinediesel or ethylene.
- the reformation. Changes the structure of hydrocarbons in order to increase your octane or its anti-knock capacity. It is applied to gasoline to improve its quality and performance.
- the rental. It consists of joining two hydrocarbon molecules and thus forming a larger and more branched one, and is used in order to obtain high octane gasoline.
- isomerization. Changes the spatial arrangement of carbon atoms in a hydrocarbon molecule without altering its parent formula. Is used to obtain isoparaffins from normal paraffins, which have a higher octane number and a lower freezing point.
- hydrogenation. It consists of adding hydrogen atoms to the hydrocarbon molecules and thus reducing the sulfur, nitrogen or oxygen content. Is used for improve the environmental quality of fuels and prevent equipment corrosion.
- Sulfuric acid treatment. Reacts acid with hydrocarbons to remove organic impurities such as olefins and aromatics. Applies to Naphthas or light fractions of crude in order to obtain suitable merchandise for the petrochemical industry.
In summary, when refining crude oil, finished products are obtained, such as LPG, gasoline, kerosene, diesel, fuel oil, asphalt or tar, as well as intermediate products that serve as the basis for gas stations or other branches/areas of the petrochemical industry.
How important is the oil refining process?
This is a very important process to obtain products that satisfy the needs of society in terms of energy and materials, however involves a high consumption of energy and natural resourcesas well as a generation of polluting emissions and hazardous waste.
For all these reasons, it is necessary to optimize the refining process to improve your efficiency and reduce your impact in the environment.
How polluting is oil refining?
This process generates a large amount of environmental poisoning, which affects the environment and human health. It also produces greenhouse gas emissions that contribute to climate change.
Oil refining pollutes through three ways:
- ground pollution. It is a consequence of crude oil spills that occur during the transport or extraction of black gold, in addition to leaks or breaks in pipes or storage tanks. These spills contaminate the soil and aquifers and can affect the terrestrial flora and fauna. In addition to this, refineries generate hazardous waste such as sludge, ash, acids and heavy metals, which have to be treated to prevent their dispersion.
- pollution by sea. It is due to oil spills that occur in the oceans or rivers due to accidents involving oil tankers or offshore platforms, as well as intentional or accidental discharges from the refineries. These discharges affect the ecosystems of the sea and the coast, causing the death of thousands of animals and aquatic plants and damaging fishing and tourism. In addition, oil can form a surface layer that prevents the exchange of oxygen and light between the water and the atmosphere.
- air pollution. It comes from the emissions of toxic gases that are produced during the combustion of petroleum or its derivatives, or in the distillation and refining processes. These can cause respiratory, cardiovascular and carcinogenic problems in people who inhale them. They also contribute to the formation of acid rain and smog and, in addition to this, the burning of crude oil produces carbon dioxide, which is the main gas responsible for global warming.
Oil refining is a highly polluting activity that has serious consequences for the planet and life. It is necessary to look for cleaner and more sustainable alternatives In this way, we can satisfy our needs without compromising the future.