The principle of biomethanization
Biomethanization is a process of revalorizing residual organic matter to extract biogas. The composition of this biogas varies somewhat, but in general it is mainly composed of methane (60% to 85% depending on the case) and carbon dioxide (about 35%), water vapour, ammonia, hydrogen gas (H2) and hydrogen sulphide. The biogas, once dried and cleaned, is used as a fuel for power generators, fuel cells, gas boilers or can be used for a variety of other energy uses. The gas is produced in a digester through an anaerobic fermentation process of organic matter.
Which raw materials do we need to produce biogas?
Raw materials mainly consists of organic residual materials of agricultural origin and from companies in the agri-food sector, as well as municipal sludge.
– Pig slurry
– Septic tank sludge
– Sewage water
– Food residues of domestic origin
– Residual materials from the food industry
– Plant residues
The process combines environmental benefits with economic benefits. Organic residual materials represent an interesting source of alternative energy while considerably limiting greenhouse gas emissions resulting from traditional methods of storage, landfilling, and incineration or spreading in the case of pig manure.
Solugen – a contribution to the process
In anaerobic digestion, the large percentage of water contained in the manure (90%) generates significant costs in transportation, biomethanization infrastructure (digesters), and affects the very size of the digesters, and hence their cost. The same is true for other inputs with high water content.
Solugen can intervene in the process by carrying out a two-phase based pre-treatment:
- Carry out a liquid-solid separation that generally extracts 84% of the water contained in the manure. The advantage is that the slurry is converted into an input for the dry digestion technique and the volumetric efficiency of the digesters is increased.
- The subsequent treatment of the liquid enables the recovery of water and fertilisers.
The two processes thus complement each other in a logic of circular economy in a context of environmental preservation and limitation of climate changes.