Natural gas, also called fossil gas, is often just referred to as gas. This should not be confused with the colloquial American use of the word which usually means gasoline and is made from crude oil. Natural gas is truly a gas and is primarily composed of methane. In smaller amounts it can also contain carbon dioxide, nitrogen, hydrogen sulfide and helium.
Natural gas has been used for centuries and even before it could be extracted civilizations used the gas that seeped through the earth’s surface to heat water but where does natural gas come from?
The most basic answer to that question is that much like carbon atoms crystallize under the immense pressure and heat within the earth’s crust to form diamonds so too does natural gas form from the remains of plants and animals buried within the earth. These plants and animals have carbon and hydrogen (carbohydrates) stored within themselves that they received through the natural food chain millions of years ago. Over time the decomposing remains of these organisms created a thick layer on the earth’s surface and ocean floor and were covered under sediment of sand, silt and rock. As the layers over the organisms increase so too does the heat and pressure and over time the carbon- and hydrogen-rich material is transformed into three things – coal, oil or natural gas.
Natural gas can often be found alongside other fossil fuels like oil and coal either on land or offshore deep under the ocean floor. Furthermore, natural gas can be labeled as conventional or unconventional natural gas depending on the natural formations it is found in. Conventional natural gas is trapped under the earth’s surface in pockets or reservoirs by a layer of rock. Once a drill is sunk into the reservoir the gas can escape under its natural pressure. Unconventional natural gas is trapped within the rock itself and the gas cannot escape under natural pressure. Other methods need to be employed by drilling companies to extract this gas.
Once gas is extracted it must be processed and purified before it can be used by consumers. The purification of gas can create by-products like ethane, propane, butane, carbon dioxide, water vapor, helium and nitrogen. Some of these byproducts also have commercial value and can be sold and as natural gas produces less CO2 than the usage of other fossil fuels it is thought of as the cleaner option. Though natural gas is an odorless and colorless gas an agent is added to give it an odor thus making it safer with the possibility to detect a gas leak.
Many countries all over the world extract and produce natural gas but the leading countries in this production are the USA, Russia, Iran, Qatar and Canada. With natural gas’ lower air polluting emissions its production is expected to increase but with some legal limitations still crippling the export of natural gas from America, for example, it will take time to surpass the demand and trade in other fossil fuels.