Alternative utilization of protein-rich waste by its conversion into biogas in co-fermentation conditions

The recommended process conditions and problems reported during anaerobic (co-)fermentation of waste biomass rich in proteins are discussed. Theoretical potentials of the individual biogas components (CH₄, CO₂, NH₃, H₂S) formed during chemical decomposition of aminoacids feed additives commonly used in feeding animals are shown, and we discuss side production of odors, e.g., ammonia and organic sulphur compounds. We also suggest the potential alternative production of biohydrogen (a future energy carrier) from specific waste biomass with high protein content.