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

• Published in: Bioresource technology 2017-02, Vol.226, p.65-72
• Main Authors: Kuruti, Kranti, Begum, Sameena, Ahuja, Shruti, Anupoju, Gangagni Rao, Juntupally, Sudharshan, Gandu, Bharath, Ahuja, Devender Kumar
• Format: Article
• Language: English
• Subjects: Acidification; Anaerobic gas lift reactor (AGR); Anaerobiosis; Biofuels; Biogas; Biological Oxygen Demand Analysis; Bioreactors; Cooking; Food; Food waste; Hydrogen-Ion Concentration; Manure; Methane - biosynthesis; Rice gruel; Waste Management - instrumentation; Waste Management - methods
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.12.005

[Display omitted] •High rate biomethanation of food waste for the production of biogas and bio manure.•Exploiting rapid acidification phenomena of food waste for the reduction of HRT.•Effect of co-digestion of food waste and rice gruel on biogas yield.•140m3 of biogas and 110kg of bio manure was generated from one ton of food waste.•60–70kg of LPG was replaced with 140m3 of biogas produced per day. The aim of the present work was to study and infer a full scale experience on co-digestion of 1000kg of FW (400kg cooked food waste and 600kg uncooked food waste) and 2000L 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 12h in the feed preparation tank that facilitated to obtain a lower hydraulic residence time (HRT) of 10days. At full load, AGR was fed with 245kg of total solids, 205kg of volatile solids (167kg of organic matter in terms of chemical oxygen demand) which resulted in the generation of biogas and bio manure of 140m3/day and 110kg/day respectively. The produced biogas replaced 60–70kg of LPG per day.