Biomethane production from starch and lignocellulosic crops: a comparative review

Abstract

The methane produced from the anaerobic digestion of organic wastes and energy crops represents an elegant and economical means of generating renewable biofuel. Anaerobic digestion is a mature technology and is already used for the conversion of the organic fraction of municipal solid wastes and excess primary and secondary sludge from waste‐water treatment plants. High methane yield up to 0.45 m3 STP CH4/kg volatile solids (VS) or 12 390 m3 STP CH4/ ha can be achieved with sugar and starch crops, although these cultures are competing with food and feed crops for high‐quality land. The cultivation of lignocellulosic crops on marginal and set‐aside lands is a more environmentally sound and sustainable option for renewable energy production. The methane yield obtained from these crops is lower, 0.17–0.39 m3 STP CH4/kg VS or 5400 m3 STP CH4/ha, as its conversion into methane is facing the same initial barrier as for the production of ethanol, for example, hydrolysis of the crops. Intensive research and development on efficient pre‐treatments is ongoing to optimize the net energy production, which is potentially greater than for liquid biofuels, since the whole substrate excepted lignin is convertible into methane. Copyright © 2010 Crown in the right of Canada

Modelling the socio-economic impacts of modern bioenergy in rural communities in Ghana

“…However, using crop residues as feedstock for bio-digesters has challenges with respect to the yield of methane. Methane yield is affected by the composition and biodegradability of lignocelluose due to the recalcitrant nature of lignin (Frigon and Guiot, 2010;Chandra et al, 2012). These issues are the subject of ongoing technical research (Brown and Li, 2013;Chandra et al, 2012;Muhammad Nasir et al, 2012;Appels et al, 2011;Wu et al, 2010;Schievano et al, 2009;Xu and Li, 2012;Brown et al, 2012;Liew et al, 2012;Cui et al, 2011;Li et al, 2011).…”

Recent Trends in Biodiesel and Biogas Production

“…Anaerobic digestion (AD) is a biological process in which organic matter is decomposed by range of microorganisms under oxygen-free conditions producing biogas (139). The AD process can be divided into four steps (hydrolysis, acidogenesis, acetogenesis/dehydrogenation, and methanation).…”

“…Among them, sugar beet, corn (grain) and potatoes are the most intensively studied, but many other les conventional starchy crops with potential for biogas utilization have been reported too (139).…”

“…In contrast to liquid biofuels (biodiesel and bioethanol), a step for product separation is unnecessary, as the biogas distillates off by itself from the liquid (139). Beside methane and carbon dioxide, raw biogas also contains trace amounts of other components such as water (H2O, 5-10 %), hydrogen sulphide (H2S, 0.005-2 %), siloxanes (0-0.02 %), halogenated hydrocarbons (VOC, < 0.6 %), ammonia (NH3, <1 %), oxygen (O2, 0-1 %), carbon monoxide (CO, <0.6 %) and nitrogen (N2, 0-2 %), and they might be inconvenient if not removed (134 Please note that this is an unedited version of the manuscript that has been accepted for publication.…”

Performance Evaluation of Brewery Biological Wastewater Treatment Plant

“…Methanogenesis process is inhibited by an imbalanced Anaerobic Digestion caused by high organic loading and C/N ratio, accumulation of VFA and low pH [21]. Anaerobic treatment method through AHR is used to remove overall COD and BOD.…”