Bio-inspired processes applied to anaerobic digestion

For millions of years, animals have optimized the transformation of all types of biomass via anaerobic digestion. Our goal is to understand why they are much more efficient than industrial digesters and to copy them. Three aspects are studied: mechanical pretreatments, digestion processes and microbiota.

4 solutions from the living, to pre-treat mechanically

 

 

Six types of mechanical pretreatment were identified (cutting, tearing, breaking, grinding, abrading and hitting). It can be seen that animals mostly grind the biomass to facilitate its digestion (yellow) but do not smash it (black), whereas industrial grinders cut or smash the biomass (blue).

5 solutions from the living, to digest [1]

Among other things, we note :

• The presence of a chemical pre-treatment, acidic in vertebrates and basic in insects.
• The presence of a microbial compartment upstream when the food is difficult to degrade (cellulose of plants or chitin of crustaceans)

These 'solutions' are currently being tested for the construction of bio-inspired technologies

References

[1] Godon, JJ., Arcemisbéhère, L., Escudié, R. et al. Overview of the Oldest Existing Set of Substrate-optimized Anaerobic Processes: Digestive Tracts. Bioenerg. Res. 6, 1063–1081 (2013). https://doi.org/10.1007/s12155-013-9339-y
[2] Dieudonné, A., Battimelli, A., Steyer, JP. et al. Mechanical Pretreatment of Various Types of Biomass from Animals: What Potential Applications to Anaerobic Digestion?. Bioenerg. Res. 16, 761–777 (2023). https://doi.org/10.1007/s12155-022-10518-x