title: Biological pretreatment of non-flocculated sludge augments the biogas production in the anaerobic digestion of the pretreated waste activated sludge.
abstract: High-efficiency resource recovery from municipal solid waste (MSW) has been a focus of attention. The objective of this research is to develop a bio-pretreatment process for application prior to the anaerobic digestion of MSW to improve methane productivity. Bacillus licheniformis was used for pretreating MSW (non-flocculated with 0.07% citric acid), followed by anaerobic digestion. Laboratory-scale experiments were carried out in semi-continuous bioreactors, with a total volume of 5 L and working volume of 3 L. Among the nine organic loading rates (OLRs) investigated, the OLR of 0.84 kg SS m(-3) reactor day(-1) was found to be the most appropriate for economic operation of the reactor. Pretreatment of MSW prior to anaerobic digestion led to 55% and 64% increase of suspended solids (SS) and volatile solids reduction, respectively, with an improvement of 57% in biogas production. The results indicate that the pretreatment of non-flocculated sludge with Bacillus licheniformis which consumes less energy compared to other pretreatment techniques could be a cost-effective and environmentally sound method for producing methane from MSW.
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: J
authors.initials: J
authors.lastname: Merrylin
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: S Adish
authors.initials: SA
authors.lastname: Kumar
authors.affiliation: Department of Civil Engineering, Ponjesley College of Engineering, Nagercoil, India.
authors.forename: S
authors.initials: S
authors.lastname: Kaliappan
authors.affiliation: Department of Civil and Environmental Engineering, Sungkyunkwan University, Seoul, South Korea.
authors.forename: Ick-Tae
authors.initials: IT
authors.lastname: Yeom
authors.affiliation: Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, India.
authors.forename: J Rajesh
authors.initials: JR
authors.lastname: Banu
mesh_terms: D000693:Anaerobiosis; D001407:Bacillus / Q000378:metabolism; D056804:Biofuels; D019149:Bioreactors; D005232:Fatty Acids, Volatile / Q000032:analysis / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000378:metabolism; D012037:Refuse Disposal / Q000379:methods; D012722:Sewage; D062611:Solid Waste
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D012722:Sewage; D062611:Solid Waste; D008697:Methane