Biogas Production From Industrial Effluents

Abstract Industrial wastewater is a cheap source of organic material to convert to biogas. Their suitability depends on the biodegradable content generally represented in a form of chemical oxygen demand (COD), but some distinct characteristics such as impurities and other defective constituents could play an important role to dictate the potential for methane generation. In this section, the proven potential wastewaters of major industries are presented namely brewery, animal farm, meat processing, ethanol, starch, palm oil mill, biodiesel, and seafood processing. While usually containing high organic carbon, its balance with nitrogen content is always discussed as a key parameter for an effective methanation. High nitrogen content in animal waste prompts an onset of co-digestion with other carbon-rich waste steam including lignocellulosic biomasses, while nutrient supplement to biodiesel wastewater reportedly enhances biogas production. Oil contamination in wastewaters from palm oil mill and seafood processing could cause scum floats in the anaerobic digester and clogging in pipes had attention not been duly paid. Anaerobic digestion of a less concentrated but large in volume waste stream from seafood processing plants, although not giving high return in biogas, provided a great incentive in cost cutting from aeration requirement in the following aerobic treatment. These days, anaerobic digestion systems have become an integral part in these industries not only as treatment systems, but also as an effective energy production unit to help cut the energy cost. In each section, challenges and future directions of these wastewater steams at various aspects are discussed.