Mesophilic anaerobic digestion of food waste: Effect of thermal pretreatment on improvement of anaerobic digestion process

The treatment of food waste (FW) is an important challenge in developed and undeveloped countries due to the rapid disintegration of this waste. Hence biogas technology is used to produce energy and to reduce the volume of waste. This technology has disadvantages in terms of sensitivity to nutritional imbalance and low biodegradability. In this case, several pretreatments have been applied to improve biogas production such as thermal pretreatment (TP). This study investigated the effects of TP on physico-chemical properties and methane yield (MY) improvement. With the effect of temperature and time treatment, soluble COD was increased and reaching 68.54 ± 2,4 mg/L recorded at (100 °C, 30 min), which was 43. 41% higher than control. In contrast, TP decreased the percentage of VS compared to the raw FW. Furthermore, anaerobic digestion (AD) of FW pretreated at 100 °C during 30min was tested, the MY was (382.82 mLSTP CH4/ g VS) which 23.68 % higher than untreated food waste. Biodegradability was increased from 83.2 ± 3 % to 91.4 ± 4.1 % showing an increase of 9.8 %.