Julian's Science Fair
Projects by Grade Level
1st 2nd 3rd 4th 5th 6th
7th 8th 9th 10th 11th 12th
Home Primary School Elementary School Middle School High School Easy Projects Advanced Award Winning Popular Ideas
   

Renewable energy science fair project:
Methanogenic bacteria subjected to anaerobic conditions produces biogas




Science Fair Project Information
Title: Methanogenic bacteria subjected to anaerobic conditions produces biogas
Subject: Renewable Energy
Grade level: Middle School - Grades 7-9
Academic Level: Ordinary
Project Type: Experimental
Cost: Medium
Awards: 2nd place, Canada Wide Virtual Science Fair (2007)
Affiliation: Canada Wide Virtual Science Fair (VSF)
Year: 2007
Description: This project demonstrates that if methanogenic bacteria are subjected to anaerobic conditions than it will result in the production of methane which could be used as a possible clean, alternative energy source (biogas). Then is calculated how much gas is produced and what generator requirements are needed in order to be practical.
Link: http://www.odec.ca/projects/2007/sidd7g2/
Short Background

Methanogenesis or biomethanation is the formation of methane by microbes known as methanogens. Organisms capable of producing methane have been identified only from the kingdom Archaea, a group phylogenetically distinct from both eukaryotes and bacteria, although many live in close association with anaerobic bacteria. The production of methane is an important and widespread form of microbial metabolism. In most environments, it is the final step in the decomposition of biomass.

Recently, some experiments have suggested that leaf tissues of living plants emit methane. Other research has indicated that the plants are not actually generating methane; they are just absorbing methane from the soil and the emitting it through their leaf tissues. There may still be some unknown mechanism by which plants produce methane, but that is by no means certain.

Methanogenesis is the final step in the decay of organic matter. During the decay process, electron acceptors (such as oxygen, ferric iron, sulfate, nitrate, and manganese) become depleted, while hydrogen (H2) and carbon dioxide accumulate. Light organics produced by fermentation also accumulate. During advanced stages of organic decay, all electron acceptors become depleted except carbon dioxide. Carbon dioxide is a product of most catabolic processes, so it is not depleted like other potential electron acceptors.

Only methanogenesis and fermentation can occur in the absence of electron acceptors other than carbon. Fermentation only allows the breakdown of larger organic compounds, and produces small organic compounds. Methanogenesis effectively removes the semi-final products of decay: hydrogen, small organics, and carbon dioxide. Without methanogenesis, a great deal of carbon (in the form of fermentation products) would accumulate in anaerobic environments.

Methane in the Earth's atmosphere is an important greenhouse gas with a global warming potential 21 times greater than carbon dioxide (averaged over 100 years), and methanogenesis in livestock and the decay of organic material is thus a considerable contributor to global warming. It may not be a net contributor in the sense that it works on organic material which used up atmospheric carbon dioxide when it was created, but its overall effect is to convert the carbon dioxide into methane which is a much more potent greenhouse gas.

Methanogenesis can also be beneficially exploited, to treat organic waste, to produce useful compounds, and the methane can be collected and used as biogas, a fuel.

The presence of atmospheric methane has a role in the scientific search for extra-terrestrial life. The argument being that methane in the atmosphere will eventually dissipate, unless something is replenishing it. This an be detected (by using a spectrometer for example) then that means there is, or relatively recently was, life present. This was debated when methane was discovered in the Martian atmosphere by (among others) the Mars Express Orbiter (2004) and in Titan's atmosphere by the Huygens probe (2005). It is also argued that atmospheric methane can come from volcanoes or other fissures in the planet's crust and that without an Isotopic signature it is difficult to say what exactly was the origin.

Bio-gas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. Biogas originates from biogenic material and is a type of biofuel.

One type of bio-gas is produced by anaerobic digestion or fermentation of biodegradable materials such as biomass, manure or sewage, municipal waste, green waste and energy crops. This type of biogas comprises primarily methane and carbon dioxide. The other principal type of biogas is wood gas which is created by gasification of wood or other biomass. This type of biogas is comprised primarily of nitrogen, hydrogen, and carbon monoxide, with trace amounts of methane.

Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License)

For More Information: Build Your Biogas Generator

Useful Links
R=Reference
Science Fair Projects Resources R
Solar Energy (Cells & Panels) Resources R
Citation Guides, Style Manuals, Reference R
Electrical Safety R R



The Solar Car Book
A complete kit for making a cool solar racecar.
Everything is included: wheels, axles, motors, wires and a genuine one-volt solar cell.





Follow Us On:
     

Privacy Policy - About Us

Comments and inquiries could be addressed to:
webmaster@julianTrubin.com


Last updated: June 2013
Copyright 2003-2013 Julian Rubin