Mesophilic and Thermophilic Anaerobic Digestion of Model Kitchen Waste with Variation of Fat Content

Anaerobic digestion of model kitchen waste (MKW) produced on basis of real kitchen waste (KW) is studied in batch tests. The impact of fat content of three MKWs (14.7 %, 23 %, and 27.2 % rapeseed oil content) on the biogas production at mesophilic and thermophilic conditions and two loadings is examined. The loading of 5 gVSL−1 leads to fast degradation under both temperature modes and the volume of biogas produced is only weakly correlated to the oil content. For the loading of 25 gVSL−1 a strong retardation of biogas production, high concentration of volatile fatty acids and no correlation of oil content is observed. The impact of fat content on the anaerobic digestion of three model kitchen waste types, with 15 %, 23 % and 27 % oil content, produced on basis of real kitchen waste is studied in batch tests, at mesophilic and thermophilic conditions and at two loadings.