Mesophilic Anaerobic Digestion of Mechanically Sorted Organic Fraction of Municipal Solid Waste

The mechanically sorted organic fraction of municipal solid waste (MS-OFMSW) from Wuzhou was divided into above screen fraction (AS-MS-OFMSW) and below screen fraction (BS-MS-OFMSW). The experimental results showed that, the volatile solid (VS) of AS-MS-OFMSW was 28.6% with biodegradable VS of 82.5%. A VS removal of 19.7% and a methane yield of 93.1 L/kgVS were obtained in mesophilic digestion with TSr 20%. In case of BS-MS-OFMSW, the VS content was 17.1%. The methane yield and VS removal were 37.3 L/kgVS and 9.5% respectively. The nutrition content in solid fraction of digested residue satisfied the requirement of Chinese standards. However, four heavy metal contents (Cr, Cd, Pb and Ni) were beyond the allowed levels.