Gas Use Devices
While a variety of gas use options are available, the collected biogas is most often used to generate electricity for on-farm use or sale to the local electric utility. Thermal energy in the form of waste heat, produced during electricity generation, can be recovered to heat digesters or adjacent buildings. Other uses include:
- Heat generation by burning biogas in boilers
- Upgrading biogas to pipeline quality
- Converting biogas to compressed natural gas (CNG) for a variety of fuel applications
A 120 kW engine generator set combusts recovered biogas, generating electricity for on-farm use.
A heat exchanger works in conjunction with an engine-generator set to recover heat for space and water heating, thus reducing fuel oil or propane costs.
Biogas can be fired directly in boilers or heaters as a replacement for propane.
Flares are used to combust excess biogas or to combust biogas during periods when the primary gas use device is undergoing maintenance or repair. In cases where the primary purpose of the digester is odor control or the generation of carbon credits, all of the biogas may be flared.
Biogas can be cleaned to pipeline quality and sold to the local gas utility.
Biogas can be converted to compressed natural gas (CNG) which can be used in applications such as vehicle fuel.
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