4. Adding value to co-products

The valorization of co-products from microalgae processing has been little studied, yet it is essential given the limited fraction of biomolecules valorized in some cases. It depends on the operations undergone by the biomass during refining. When the composition is compatible, notably without additives or chemicals, the residue can be used for animal feed (e.g. aquaculture, poultry, pigs). Otherwise, it can be used for soil fertilization (biofertilizers, biostimulation, biocides). Often recommended as a co-substrate for anaerobic digestion, energy recovery through thermochemical conversion is also being studied, whether by pyrolysis, gasification or torrefaction