Biogas from Lignocellulosic Materials

Methane production via anaerobic digestion is a steadily growing industry in Europe and all over the world. Biomethane reduces the demand for fossil fuels, since it can be used for the production of power and heat, or converted to vehicle fuel. Anaerobic digestion is a renewable energy technology, however it can also be considered as a low-cost environmental friendly waste management process, since it reduces the emission of greenhouse gases (GHGs), while it stabilizes the wastes. Currently, mainly the organic fraction of household waste, food waste, sewage sludge, manure and energy crops are used for biogas production, however there are a wide range of other organic substrates which can be utilized for biogas production. Lignocellulosic materials have a great potential. Their great abundance worldwide and their carbohydrate rich property make them an attractive feedstock for biofuel production. Currently, anaerobic digestion of energy crops is widespread, however, biogas production from lignocellulosic residuals and wastes are still under investigation.
This chapter focuses on anaerobic digestion of lignocellulosic materials. It explains the anaerobic digestion process and the current technologies used for crops digestion. It also summarizes the biogas potential of different lignocellulosic materials and the latest research on pretreatments to improve the methane yield. Finally, this chapter compares anaerobic digestion of lignocellulosic materials with energy production from these kinds of materials through thermo-chemical processes.