title: Biological activity in the composting reactor of the bio-toilet system.
abstract: The bio-toilet is becoming commercially available and it is actually used in Japan in public parks, sightseeing areas, and households; however, the biological activity in the system during degradation of toilet wastes, particularly faeces, is unknown. Thus, in this study activity of microorganisms in the bio-toilet system during degradation of faeces was assessed through the quantification of reductions in total solids (TS), volatile solids (VS), and chemical oxygen demand (COD) during batch tests in laboratory-scale composting reactors. Additionally, the fate of nitrogen and its transformation processes in such reactors were evaluated. TS, VS, and COD reductions were on the order of 56%, 70%, and 75%, respectively, irrespective of the organic loading regarded. Total nitrogen (T-N) reductions quantified 94%, regardless of the organic loading. Furthermore, all T-N reductions observed during composting were equivalent to the NH(3)-N released from the reactor, i.e., 94% of ammonia was lost.
authors.affiliation: Department of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku Sapporo 060-8628, Japan. lozm@eng.hokudai.ac.jp
authors.forename: M A Lopez
authors.initials: MA
authors.lastname: Zavala
authors.forename: N
authors.initials: N
authors.lastname: Funamizu
authors.forename: T
authors.initials: T
authors.lastname: Takakuwa
mesh_terms: D000332:Aerobiosis; D019149:Bioreactors; D005243:Feces; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology / Q000295:instrumentation / Q000379:methods*; D009584:Nitrogen / Q000378:metabolism; D012037:Refuse Disposal / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data*; D012987:Soil; D014038:Toilet Facilities
chemical_list: D012987:Soil; D009584:Nitrogen