Anaerobic digestion is the biochemical decomposition of organic matter by bacteria in the absence of oxygen, producing biogas (methane) and fertilizer. Biogas is better than directly burning biomass but cannot compete with fossil fuels. However, biogas has advantages as it is renewable and free. Biogas can be used for direct consumption like water and cooking heating or converted to electricity. Anaerobic digestion also provides economic and environmental benefits such as energy autonomy, reduced fertilizer costs, organic waste processing, and pollution reduction.
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Rhea International Team - Biogas
1.
2. ANAEROBIC DIGESTION
Also called biomethanisation, is the
biochemical decomposition of complex
organic matter by different activities
performed by bacteria, in the absence
of oxygen.
The two main products are biogas
(methane) and a mixture of biomass and
bacteria, that can be used as a fertilizer.
Bio-digesters
3. Bio-digesters
Biogas: Performance comparison
Biogas can't compete with fossil fuels, of course, but is way better than burning
directly biomasses like wood or cow dung.
The great advantage of biogas, in comparison to fossil fuels, is that biogas is free and
renewable!
4. Bio-digesters
Biogas: Applications
DIRECT CONSUMPTION: Water heating
DIRECT CONSUMPTION: Cooking
ENERGY CONVERSION: Electricity production
through generators or fuel cells
SELLING
5. Energetic autonomy in a context of increased cost of fossil energy;
Reduction in the purchase of fertilizer through the valorisation of produced biomass;
Transformation of manure in organic fertilizer, more easily assimilated by plants, with
reduction of odors and disease-causing agents.
Processing of organic waste at competitive prices; more than 50% of garbage is
organic and biodegradable.
Reduction of the pollution in the environment.
Bio-digesters
Economic and environmental advantages
7. Handling system
(pulley)Biomass storage
(batch)
Pulley – to reduce
weight
Coverage to protect the bio-
digester against UV rays
Bio-digester
SEPARATION OF THE SOLID PHASE FROM
THE LIQUID THROUGH PERCOLATION
- SOLID (10%) used as fertilizer
- LIQUID (90%): NH3 for agronomic use (to be
buried in low depth to avoid the release of N2)
Bio-digesters
Installation
