Treating the source-separated organic fraction of municipal solid waste (SS-OFMSW) by anaerobic digestion is considered by many
municipalities in Europe as an environmentally friendly means of treating organic waste and simultaneously producing methane gas.
Methane yield can be used as a parameter for evaluation of the many different systems that exist for sorting and pre-treating waste.
Methane yield from the thermophilic pilot scale digestion of 17 types of domestically SS-OFMSW originating from seven full-scale
sorting systems was found. The samples were collected during 1 year using worked-out procedures tested statistically to ensure representative
samples. Each waste type was identified by its origin and by pre-sorting, collection and pre-treatment methods. In addition to the
pilot scale digestion, all samples were examined by chemical analyses and methane potential measurements. A VS-degradation rate of
around 80% and a methane yield of 300–400 Nm3 CH4/ton VSin were achieved with a retention time of 15 days, corresponding to
70% of the methane potential.
The different waste samples gave minor variation in chemical composition and thus also in methane yield and methane potential. This
indicates that sorting and collection systems in the present study do not significantly affect the amount of methane produced per VS
treated.