The word petroleum derives from the words petro (stone) and oleum (oil); that is to say, " stone oil ". Also known as "crude" or "crude oil", it is a complex mixture of liquid hydrocarbons, composed to a greater extent of carbon and hydrogen; with small amounts of nitrogen, oxygen and sulfur, formed by the decomposition and transformation of animal and plant remains that have been buried at great depths for several centuries.
The presence in various amounts of each of the chemical elements (organic and inorganic) that make up oil, determine its particular characteristics such as color, density, viscosity, among others.
Due to its chemical composition, it can be classified as: Paraffinic; whose main component is the chemical compound called paraffin, it is very fluid and light in color. The Naphthenic and its main components the naphthenes and aromatic hydrocarbons, is a very viscous dark colored oil. And the Mixed, which presents both types of compounds.
The use of oil by man dates back almost 5000 years, mostly for limited purposes, such as caulking ships, waterproofing fabrics or making torches, obtaining lubricants and medicinal products, but the true exploitation of the Oil didn't start until the 19th century. By then, the Industrial Revolution had sparked a search for new fuels, and social changes required good, cheap oil for lamps.
Today in the oil industry four major processes are carried out to obtain it, which are: exploration (studies on the surface such as field geology and topography of the land predominate to find areas with oil), production (drilling of a oil well and its exploitation), refining (a set of procedures and operations that allow the elaboration of derivatives of greater economic value from raw material), among them we have distillation, alkylation, hydrotreating, thermal cracking, among others. And finally, there are trade and supply.
Oil is the most important non-renewable natural resource for society because it needs it to meet many of its energy needs. Petroleum derivatives (gasoline and liquefied petroleum gases) are today the main fuels used both in transport, as well as in the generation of electricity and heating. It is also used as a raw material for the chemical industry.
However, in recent years the global availability of this material has decreased, and its relative cost has increased. According to experts, they calculate the probability that the supply of crude will only last until the first decades of the 21st century.
