Exploitation of rapid acidification phenomena of food waste in reducing the hydraulic retention time (HRT) of high rate anaerobic digester without conceding on biogas yield

The aim of the present work was to study and infer a full scale experience on co-digestion of 1000 kg of FW (400 kg cooked food waste and 600 kg uncooked food waste) and 2000 L of rice gruel (RG) on daily basis based on a high rate biomethanation technology called Anaerobic gas lift reactor (AGR). The pH of raw substrate was low (5.2-5.5) that resulted in rapid acidification phenomena with in 12 h in the feed preparation tank that facilitated to obtain a lower hydraulic residence time (HRT) of 10 days. At full load, AGR was fed with 245 kg of total solids, 205 kg of volatile solids (167 kg of organic matter in terms of chemical oxygen demand) which resulted in the generation of biogas and bio manure of 140 m(3)/day and 110 kg/day respectively. The produced biogas replaced 60-70 kg of LPG per day. (C) 2016 Elsevier Ltd. All rights reserved.