(RHIE) How is Natural Gas Made? Lesson

How is Natural Gas Made?

Natural gas forms under the same conditions that create oil. Microorganisms, sea plants and animals died over 300 million years ago, even before the dinosaurs, they settled on the bottom of the oceans which covered most of the earth. Layers of dead sea plants, animals, sand, mud, and other debris built up over time and the pressure and heat from the earth turned them into petroleum and natural gas. The natural gas would get trapped in pockets of underground rocks. Sometimes the gas would seep up to the earth's surface and dissipate into the air or ignite from lightning strikes.

Natural gas in it's pure form is colorless, odorless and shapeless. Only after processing is the "rotten egg" odor added for safety. It is a combination of several gases like propane, butane, carbon dioxide, ethane, oxygen, nitrogen and hydrogen sulfide, but primarily made up of methane gas so when you burn it heat energy is released. There are some renewable sources for methane like garbage in landfills that produce some gas.

The main ingredient of gas is methane, a gas, made by mixing one carbon atom and four hydrogen atoms. Millions of years ago, remains of plants and animals decayed and built up in thick layers. These decayed materials from plants and animals are called organic material – they were once alive. Over time, the sand and silt changed to rock, covered the organic material, and trapped it below the rock. Pressure and heat changed some of the organic material to coal, some into oil (petroleum), and some turned into natural gas – tiny bubbles of odorless gas.

Natural gas is a compound formed by the decomposition of organic material beneath the surface of the Earth. (CH4)

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Natural Gas Use

The largest natural gas reserves in the United States are located in the Rocky Mountain states, Texas, and the Gulf of Mexico region. California also has natural gas, mostly in the northern Sacramento Valley and the Sacramento Delta.

Natural gas must be processed before it can be used as a fuel. Poisonous chemicals and water must be removed.

Natural gas is delivered to homes, where it is used for cooking and heating. Natural gas is also a major energy source for powering turbines to make electricity. Natural gas releases most of its energy as heat when it burns. The power plant is able to use this heat, either in the form of hot gases or steam, to spin turbines. The spinning turbines turn generators, and the generators create electricity.

Extracting Natural Gas

Most natural gas comes from the wells that produce petroleum. An increasing amount comes from a new method. Hydraulic fracturing, called fracking, is very much in the news lately. Fracking makes it easier and quicker to get natural gas from the rock.

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With fracking, fluids are pumped through a borehole. The fluids create fractures in the rock that contains the natural gas. Chemicals in the fluid prevent the fractures from closing. The natural gas can then be pumped to the surface.

Consequences of Natural Gas Extraction and Use

Natural gas burns cleaner than other fossil fuels. As a result, it causes less air pollution. It also produces less carbon dioxide than the other fossil fuels. Because it burns cleaner than other fossil fuels, natural gas has a good reputation. Still, natural gas does emit pollutants.

Fracking is being found to be destructive in several ways. Some of the chemicals in the fracking fluids may be harmful. Some may cause cancer. Some may be endocrine disruptors. Endocrine disruptors interrupt the natural hormones in the bodies of humans and animals. These fluids can get into the groundwater. They may runoff into streams and other surface waters. There they can cause problems.

The liquid waste injected into the deep wells may cause earthquakes. Locations where seismic activity is unknown have begun to experience earthquakes. Is fracking related to earthquake activity? Many geologists think the link is undeniable.

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