Anaerobic digestion generates a wide range of byproducts that farmers can use in their farming operations or sell. Beyond biogas used to generate electricity or as fuel, and liquids used for fertilizer or soil amendments, there are solid byproducts, which have a wide range of applications.
The manure handling system of any farm is made up of many different components, each with a different function and purpose. An anaerobic digester, although only one component of the system, can greatly improve the environmental performance and efficiency of the overall system. The main effect of anaerobic digestion is conversion of organic matter to biogas. This conversion has many potentially beneficial environmental and management side effects.
By removing organic matter, the digester reduces the organic matter-loading and …
Benefits of Anaerobic Digestion of Manure in Reducing Pathogens
Manure is a biologically active material that hosts and supports many microorganisms and thus can seldom be considered “pathogen free.” Certain manure handling techniques and methods, however, can limit the production and multiplication of such pathogens. Common sense must be used when making manure handling decisions. Pathogens are microbes such as bacteria, viruses, protozoa, and other organisms that cause disease. These pathogens persist commonly in animal manures. For more information …
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All anaerobic digesters perform the same basic function. They hold manure in the absence of oxygen and maintain the proper conditions for methane forming microorganisms to grow. There is a wide variety of anaerobic digesters, each performing this basic function in a subtly different way. Seven of the most common digesters are described in this article. Construction and material handling techniques can vary greatly within …
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Anaerobic digestion of manure and other feedstocks produces biogas which can be burner to make energy on farms. Learn how to evaluate a feedstock and which ones to exclude for biogas production.
|Anaerobic Digester in Charlotte, VT. Photo: Caragh Fitzgerald, University of Maine.|
On-farm biogas production has long been a topic of interest for farmers, with historical records of biogas production going back several hundreds of years. In modern livestock production systems, for example, the benefits of producing biogas are significant and include:
- provision of supplemental renewable energy
- odor reduction
- reduction of emissions of greenhouse gases
- pathogen control
- waste biostabilization
- nutrients are preserved and transformed into plant-available forms
The economics of …