Effect of total solids content on methane and volatile fatty acid production in anaerobic digestion of food waste

Entitled full text(opens in a new window)|OPAC Cassino|Order document(opens in a new window)|View at Publisher| Order Document | Export | Download | Add to List | More... Waste Management and Research Volume 32, Issue 10, 12 October 2014, Pages 947-953 Effect of total solids content on methane and volatile fatty acid production in anaerobic digestion of food waste (Article) Liotta, F.a , D'Antonio, G.b, Esposito, G.a, Fabbricino, M.b, Van Hullebusch, E.D.c, Lens, P.N.L.d, Pirozzi, F.b, Pontoni, L.a a Department of Civil and Mechanical Engineering, University of Cassino and the Southern Lazio, Via Di Biasio, Cassino (FR), Italy b Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Naples, Italy c Laboratoire Géomatériaux et Environnement, Université Paris-Est, Marne-la-Vallée, France View additional affiliations View references (39) Abstract This work investigates the role of the moisture content on anaerobic digestion of food waste, as representative of rapidly biodegradable substrates, analysing the role of volatile fatty acid production on process kinetics. A range of total solids from 4.5% to 19.2% is considered in order to compare methane yields and kinetics of reactors operated under wet to dry conditions. The experimental results show a reduction of the specific final methane yield of 4.3% and 40.8% in semi-dry and dry conditions compared with wet conditions. A decreasing trend of the specific initial methane production rate is observed when increasing the total solids concentration. Because of lack of water, volatile fatty acids accumulation occurs during the first step of the process at semi-dry and dry conditions, which is considered to be responsible for the reduction of process kinetic rates. The total volatile fatty acids concentration and speciation are proposed as indicators of process development at different total solids content.