Petroleum is an oily deposit that is found deep within the earth. The word “petroleum” means rock oil.

Petroleum is the product of incompletely decayed animal and plant remains, which are buried under layer upon layer of earth and thick rock formations. This process takes millions of years.

It is a non-renewable energy source and is easily flammable. Its makeup is mostly of hydrocarbons, but also has a bit of sulphurous and nitrogenous compounds.

If it contains a lot of sulphur it is called “sour”, and if it contains a small amount of sulphur, it is called “sweet”.

Petroleum is also called crude oil, because natural processes produce it, and it is a strong smelling yellowy black liquid. Petroleum is useful only after it is distilled and refined.

Crude oil is also grouped according to the weight of its molecules. If the molecules are heavy, crude oil is dark and thick like tar. If the molecules are light, the oil is a finer liquid like water.

There are many petroleum oil rich sites in the world, such as Russia, the Middle East, Mexico, China, Iran, Nigeria and certain states in America (Texas, Louisiana, Alaska, Kansas, and California).

However, the largest and most famous of these sites is the Middle East which is rich in crude oil and is therefore one of the main exporters of it.

The tricky thing about petroleum is that there is no way of knowing if a particular site is rich in petroleum without digging an exploratory well (wildcat).

Wells are often many miles deep and the petroleum then rises to the surface under its own pressure. Water, air or gas is also used to pump the oil from its deposits.

Many instruments are used to search for the presence of oil at the subsurface rock formation level. They are the gravimeter, the seismograph, and the magnetometer.

Crude oil is passed through pipelines or tanker ships from the wells to refineries. Because petroleum’s main component is hydrocarbon, the oil is refined at many different levels to separate them from one another.

An oil refinery is gigantic, as big as hundreds of football fields together, and it never stops working. It is constantly operating and has many employees working around the clock to ensure the product is manufactured and delivered.

The quantity of products extracted from one barrel of crude oil for example is more than the original barrel. The mechanism is similar to corn before it is popped. The popped corn is bigger than the corn seeds. In crude oil, there is about a 5% gain.

Crude oil is refined into petroleum products by three processes. Separation, which is the initial phase, then conversion, and finally treatment.

Separation isolates the heavy petroleum “fractions”/parts to the bottom, and allows the lighter fraction to settle on top. Separation is done through extreme boiling point and the liquids are sent into distillation towers.

Inside these distillation towers, the liquids and vapors separate according to their properties and light fractions like gasoline rise up to condense back to liquid. Likewise, those with medium fractions (kerosene, diesel) stay in the middle, while the heaviest fractions (gas oils) settle at the bottom.

In the conversion plant, two important things happen to improve the value of the gasoline. The process of “cracking” uses extreme heat to crack heavy molecules like hydrocarbon to make them lighter.

The other is called reforming, which uses heat, medium pressure and catalysts to turn low value fractions into high octane gasoline. Some plants also rearrange the molecules to increase the value of the product.

In the final treatment stage, finishing touches to the gasoline is added. During this process, many different variables are combined, like vapour pressure, proper octane blend, and other things to preserve the gas in high altitude environments.

Tank storage on a tank farm is provided for both the initial crude oil that is extracted from the wells and the final treated products.

Petroleum is used for many things, one of the famous being providing fuel energy for the transportation industry. Petroleum is also found in lubricating oils, asphalt, and in the production of alkenes plastic, for packaging frozen food, pharmaceuticals, and motor oil.

It is also used for other purposes like heating homes with propane, manufacturing deodorants, eye glasses, tires, CDs and DVDs, ink, crayons, bubble-gum’s, heart valves and even dishwashing liquids.

Three types of technologies are used to convert oil to electricity, they are conventional steam, combustion turbine, and combined cycle technology.

In conventional steam, the refined oil is burned to heat water. This water heats till it is converted to steam, which then generates electricity.

In Combustion turbine technique, the oil is burned under pressure. The product is hot exhaust gases, which power a turbine that creates electricity.

Finally, the combined cycle technology uses both these techniques. First oil is combusted using heated exhaust gases, and then electricity is generated. Once the exhaust gases are recovered, they are used to heat water in a boiler, which creates steam to power the second turbine.

during the production of electricity, nitrogen oxide, sulphur dioxide, carbon dioxide, methane, mercury, and other volatile organic compounds are released into the atmosphere. These components cause significant air and ground pollution.

There is also a huge amount of land, water and waste disposal problems. The water resources of nearby oil plants are often depleted because electricity generation from oil requires a lot of water to power the turbines and steam generators.

The by-products of these processes, such as sludge and oil residues contain a lot of toxic and hazardous waste, which affect the solid waste disposing system.

During oil drilling a number of toxic gasses get released into the atmosphere. Of them, hydrogen sulphide is most dangerous because it is highly flammable. Drilling also ruins acres and acres of wildlife land, which can never be recovered.

Not only are these gases toxic for the atmosphere and the land, they are also harmful to humans, especially those who work on the plants. The same is true of offshore drilling.

Transportation of oil, done by land, and sea also has a potential for accidents. When these do happen, the damage to wildlife, plants, fish, the soil and other surrounding things is catastrophic, because cleaning oil is extremely difficult.

One of the main economic benefits of petroleum is that it is cheaper than other fossil fuels. This economic gain applies to its transportation and availability too.

Another important economic advantage is that petroleum is a multipurpose material that can be used and substituted for many other potentially expensive materials. This again cuts down expected expenses.

An interesting fact is that despite the oil prices rising every day, the demand for the product remains constant. It is the collective influence of uncertain weather conditions, increasing demand from developing countries, uncertain political climates in reigning economies and many other factors.

Petroleum was used as an energy source and for medicinal purposes by rich Persians. In Rome too oil was used, and was called picula. The earliest oil wells were drilled in 347 AD in China.

Japanese used to refer to petroleum as burning water during the 7th century, while centuries later, Baghdad’s first roads were paved with tar.

Modern history of petroleum began with the refining of kerosene in the 19th century, and in 1859, about 2000 barrels of crude oil were produced a year.

Muhammad ibn Zakariya Razi, a Persian alchemist is known to be the first to distil petroleum in the world. The process of refining kerosene from coal was discovered by Abraham Pineo Gesner, a Canadian in 1823, and Benjamin Silliman was the first to fractionate petroleum through the distillation process in 1854.

The future of petroleum production lies in the never-ending supply of vehicles in the transportation industry. The future of petroleum prices also remain uncertain, with the OPEC countries setting low production prices, while new found oil reserves increase prices.

In the future, there is also a chance that vehicles and power plants that run on alternative energy sources may challenge the demand for petroleum.