BIOGAS DIGESTERBy: Jen Doak

What is biogas?

Biogas refers to the gas that is produced by the breakdown of organic matter in the presence of NO oxygen (anaerobic digester)

Produced by the anaerobic digestion of biodegradable waste such as manure, sewage, green waste, plant material.

Biogas consists mostly of methane (50%-80%) & carbon dioxide (20%-50%).

Biogas composed of 65% methane will yield about 600 Btu per cubic foot at low heat value.

How does it work?

Organic waste is put into a sealed tank called a digester where it is heated. Without oxygen, anaerobic bacteria consume the organic matter and produce biogas and the tanks ensure capturing all the biogas.

Biogas can be produced in landfills where organic food waste degrades in anaerobic conditions.

How does it work? (cont.) Biogas from sewage

Biogas from farms (animal waste to energy)

Advantages/Disadvantages

Advantages: Renewable, methane is relatively clean burning fuel, low cost, and little impact on environment

Disadvantages: loss of the organic waste for compost or fertilizer

Where is it produced?

2004, United States had 50 digesters in operation and 60 being planned

Since, the demand has continued to rise and many digesters have been created and are in planning phases

Seen in many parts of Europe

Replacing Conventional Energy

Unlike natural gas, biogas is renewable Does not take long to form Not costly and little risks attached to

biogas Bio gas is like a cycle:

http://www.youtube.com/watch?v=S7M-rV-T_Fk

Sources

http://wihresourcegroup.wordpress.com/2009/06/25/biogas-from-sewage-and-landfills-glamorous-no-but-a-renewable-fuel-yes/

http://www.cmlcat.com/Powered-by-Biogas.html

http://www.electrigaz.com/faq_en.htm http://www.odec.ca/projects/2007/sidd7g

2/Background.htm http://www.scientificamerican.com/article

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