title: Comparative evaluation of anaerobic digestion for sewage sludge and various organic wastes with simple modeling.
abstract: Anaerobic co-digestion of sewage sludge and other organic wastes, such as kitchen garbage, food waste, and agricultural waste, at a wastewater treatment plant (WWTP) is a promising method for both energy and material recovery. Substrate characteristics and the anaerobic digestion performance of sewage sludge and various organic wastes were compared using experiments and modeling. Co-digestion improved the value of digested sewage sludge as a fertilizer. The relationship between total and soluble elemental concentrations was correlated with the periodic table: most Na and K (alkali metals) were soluble, and around 20-40% of Mg and around 10-20% of Ca (alkaline earth metals) were soluble. The ratio of biodegradable chemical oxygen demand of organic wastes was 65-90%. The methane conversion ratio and methane production rate under mesophilic conditions were evaluated using a simplified mathematical model. There was reasonably close agreement between the model simulations and the experimental results in terms of methane production and nitrogen concentration. These results provide valuable information and indicate that the model can be used as a pre-evaluation tool to facilitate the introduction of co-digestion at WWTPs.
authors.affiliation: Recycling Research Team, Materials and Resources Research Group, Public Works Research Institute, 1-6, Minamihara, Tsukuba, Ibaraki 305 8516, Japan. Electronic address: hidaka@pwri.go.jp.
authors.forename: Taira
authors.initials: T
authors.lastname: Hidaka
authors.affiliation: Recycling Research Team, Materials and Resources Research Group, Public Works Research Institute, 1-6, Minamihara, Tsukuba, Ibaraki 305 8516, Japan.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: Recycling Research Team, Materials and Resources Research Group, Public Works Research Institute, 1-6, Minamihara, Tsukuba, Ibaraki 305 8516, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Tsumori
mesh_terms: D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D002118:Calcium / Q000737:chemistry; D003198:Computer Simulation; D005308:Fertilizers; D005502:Food; D005735:Garbage; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D008697:Methane / Q000737:chemistry; D008962:Models, Theoretical; D010100:Oxygen / Q000737:chemistry; D011188:Potassium / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage; D012964:Sodium / Q000737:chemistry; D062065:Wastewater; D018508:Water Purification
chemical_list: D002118:Calcium; D005308:Fertilizers; D008274:Magnesium; D008697:Methane; D010100:Oxygen; D011188:Potassium; D012722:Sewage; D012964:Sodium; D062065:Wastewater
keywords: Anaerobic digestion; Digested sludge; Mathematical model; Organic waste; Sewage sludge