The minute anaerobic digestion starts and biogas production begins on a technical scale chemical proposition of the substrates involved, are the starting point for the later biogas composition.
Below a possible composition is listed, giving a range of percentages, derived from empirical data:
Methane (CH4) 40-75%
Carbon dioxide (CO2) 25-55%
Hydrogen sulfide (H2S) 50-5000ppm
Ammonia (NH3) 0-1%
Water (H2O) 0-10%
Nitrogen (N2) 0-5%
Oxygen (O2) 0-2%
Hydrogen (H2) 0-1%
Biogas composition is substrate depending and can be described with the formula developed by Buswell and Boyle.