Biogas is generated from anaerobic digestion of manure and organic wastes. It primarily consists of methane (50-70%), carbon dioxide (25-50%) and water vapor (1-5%). Depending on the feedstock and anaerobic digester conditions, biogas may also contain nitrogen gas (0-5%), hydrogen sulfide (0-7,500 ppm), and ammonia (0-500 ppm). Others volatiles and particulates are trace-level components of biogas.