Introducing 

Prezi AI.

Your new presentation assistant.

Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.

Loading content…
Loading…
Transcript

David Zheng SNC 2DW

Effects of Methane Gas on humans and the environment

How can you identify Methane Gas?

At room temperature, Methane is a colourless and odourless gas. Methane is a compound found in natural gas. The common odour in natural gas comes from an added odourant, which helps people smell leaks. Methane burns easily in air, and it is not easily soluble in water. Its flame in complete combustion is blue, and when there is not enough oxygen it is an orange colour. Methane has a boiling point of −161.5 °C, and a melting point of −182.456 °C.

What is Methane Gas?

Warning

  • Methane gas is not toxic on its own, but it displaces oxygen and causes asphyxiation, a lack of oxygen to the body. This is why the odour indication in natural gas is so important. Incomplete combustion can produce carbon monoxide, which is poisonous.

Formula

Methane gas is a molecular compound, also known as carbon tetrahydride. It is also a hydrocarbon fuel. With one carbon atom and 4 hydrogen atoms per molecule, its formula is CH4.

Methane Gas Formula

Bonding

Carbon has 4 valence electrons, so it needs 4 more to get a full valence shell, becoming stable. To do this, it bonds with 4 hydrogen atoms, each with a single bond, to become stable. Each hydrogen atom now shares 2 electrons, they are also stable.

How Methane is Bonded

Uses of Methane Gas

Methane Gas has a variety of uses, most commonly as fuel through combustion. It is used to power ovens, furnaces, water heaters and even rocket fuel. Methane is also used to produce hydrogen gas on a large scale. This is done by using nickel as a catalyst and steam, which produces carbon monoxide and hydrogen gas.

Uses of Methane Gas

How is Methane used for energy?

In our homes, Methane gas comes in the form of natural gas, to power our furnaces, water heaters, and stoves. It's used as fuel by being ignited through combustion, and the flame releases heat to power our appliances.

How is Methane used for energy?

Methane used as Rocket Fuel

When liquid methane is combined with liquid oxygen, it outputs energy enough to propel a rocket. An example of this being used is the SpaceX Raptor.

Methane used as rocket fuel

History of Methane

Methane was discovered and identified by Italian physicist Alessandro Volta in a lake marsh between Italy and Switzerland. He was interested in the substance after reading Benjamin Franklin's paper on flammable air, which led him to collect gas rising from the marsh. In 1778, he found a way to isolate pure Methane Gas, and proved it to be flammable by lighting it with a spark.

History and Sources of Methane Gas

Methane can be emitted from a marsh, just how Volta discovered it

Sources of Methane

Methane is extracted from natural gas fields, which comes from a geological deposit. It can be thermogenic, which means that organic matter was broken up at a high temperature and deep below the earth's surface. Another source of methane comes from ruminants, which cannot be harvested. This includes livestock like cattle and pigs, who belch methane. This is responsible for 22% of methane emissions into the atmosphere in the US.

Natural sources of Methane

Natural gas fields occur underground, and can be harvested using machinery.

Reactions

  • How methane is produced
  • How methane is turned into energy
  • How methane is used to produce hydrogen gas

Reactions associated with Methane

Methane production

Methane is produced from rice fields, termites, and even organisms at the bottom of lakes. They turn carbon dioxide and hydrogen gas into methane gas and water. This applies to biological methane production which cannot be harvested, and not the industrial kind from underground.

Methane production

This reaction is also reversible, used when producing hydrogen gas on a large scale.

Hydrogen gas production

If hydrogen gas needs to be produced in large quantities, methane gas can be combined with water to produce carbon dioxide and hydrogen gas.

Hydrogen gas production

Another way to produce hydrogen gas is to have the same number of methane molecules as water molecules, and it produces carbon monoxide and hydrogen gas.

Then, the carbon monoxide produced can be used to make more hydrogen gas.

Complete combustion

Methane is turned into energy in homes through combustion. With complete combustion, methane reacts with oxygen to produce carbon dioxide and water.

Complete Combustion

This is an exothermic reaction. Carbon dioxide is released into the atmosphere and is harmful in large amounts to ecosystems.

Complete combustion burns with a blue flame

Incomplete combustion

Incomplete combustion happens when there is not enough oxygen to burn the fuel (methane). The products of this reaction are carbon monoxide, water, carbon monoxide and solid carbon/soot.

Incomplete combustion

Soot, a solid form of carbon, indicates that incomplete combustion is happening. This means that carbon monoxide is being released, which is toxic for humans.

Effects on human health

High levels of methane in the environment reduces oxygen taken into the body. Oxygen loss, or hypoxia causes symptoms such as:

  • Mood changes
  • Slurred speech
  • Vision problems
  • Memory loss
  • Nausea/vomiting
  • Headache
  • Numbness
  • Unconsciousness
  • Breathing/heart rate changes

Effects on human health

Pressurized liquid methane coming in contact with skin can cause frostbite

Effects of carbon monoxide

If incomplete combustion happens in a home, carbon monoxide is released.

Effects of carbon monoxide

Carbon monoxide is poisonous to humans, colourless and odourless, so there must be detectors in homes. Common signs of poisoning include:

  • Tiredness
  • Headaches
  • Muscle weakness
  • Dizziness
  • Chest pain
  • Vision impairment
  • Difficulty thinking

Can also cause death in very high exposure

Effects on the environment

If methane is leaked into the environment, it's a greenhouse gas, like CO2. Methane contributes to global warming because of how effectively it absorbs heat. In fact, using methane for combustion as energy releases CO2, another common greenhouse gas. Increased carbon dioxide in the atmosphere increases acid in lakes. This will cause species to die, reducing biodiversity in aquatic ecosystems.

Effects on the environment

Sources

  • Leman, Jennifer. “What Is Methane, Anyway?” Popular Mechanics, Popular Mechanics, 25 Sept. 2020, www.popularmechanics.com/science/environment/a28858699/what-is-methane/#:~:text=Methane%20(CH4)%20is%20a%20colorless,carbon%20dioxide%20and%20water%20vapor.
  • Kelley, Leigh. “What Are the Dangers of Methane Gas?” Sciencing, 18 Nov. 2019, sciencing.com/what-are-the-dangers-of-methane-gas-13404265.html.
  • “Methane.” Wikipedia, Wikimedia Foundation, 13 Jan. 2021, en.wikipedia.org/wiki/Methane#Properties_and_bonding.
  • “Methane.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., www.britannica.com/science/methane.
  • Breznak, John A. “Acetogenesis from Carbon Dioxide in Termite Guts.” SpringerLink, Springer, Boston, MA, 1 Jan. 1994, link.springer.com/chapter/10.1007/978-1-4615-1777-1_11.
  • https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/769766/Methane_PHE_general_information__070119.pdf (no information to cite)
  • Canada, Health. “Government of Canada.” Canada.ca, / Gouvernement Du Canada, 15 Jan. 2021, www.canada.ca/en/health-canada/services/air-quality/indoor-air-contaminants/keep-carbon-monoxide-out-your-home.html?utm_campaign=hc-sc-healthyhome-20-21&utm_medium=sem&utm_source=ggl&utm_content=ad-text-en&utm_term=carbon+monoxide+poisoning&adv=2021-0057&id_campaign=396353411&id_source=1244647685698050&id_content=.
  • “Methane: The Other Important Greenhouse Gas.” Environmental Defense Fund, www.edf.org/climate/methane-other-important-greenhouse-gas#:~:text=If%20methane%20leaks%20into%20the,greenhouse%20gas%2C%20like%20carbon%20dioxide.
Learn more about creating dynamic, engaging presentations with Prezi