The use of laboratory scale reactors to predict sensitivity to changes in operating conditions for full-scale anaerobic digestion treating municipal sewage sludge.
Anaerobic digestion of sewage sludge is highly complex and prone to inhibition, which can cause major issues for digester operators. The result is that there have been numerous investigations into changes in operational conditions, however to date all have focused on the qualitative sensitivities, neglecting the quantitative. This study therefore aimed to determine the quantitative sensitivities by using factorial design of experiments and small semi continuous reactors. Analysis showed total and volatile solids removals are chiefly influenced by retention time, with 79% and 59% of the observed results being attributed to retention time respectively, whereas biogas was mainly influenced by loading rate, 38%, and temperature, 22%. Notably the regression model fitted to the experimental data predicted full-scale performance with a high level of precision, indicating that small reactors are subject to the same sensitivity of full-scale digesters and thus can be used to predict changes loading, retention time, and temperature.
School of Civil, Environmental and Chemical Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
James D
JD
McLeod
School of Civil, Environmental and Chemical Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
Maazuza Z
MZ
Othman
Land and Water Flagship, Commonwealth Scientific and Industrial Research Organisation (CSIRO), PO Box 56, Highett, VIC 3190, Australia.
David J
DJ
Beale
Melbourne Water, PO Box 4342, Melbourne, VIC 3001, Australia.
Deepak
D
Joshi
D000468:Alkalies / Q000494:pharmacology; D000641:Ammonia / Q000032:analysis; D000693:Anaerobiosis / Q000187:drug effects; D001673:Biodegradation, Environmental / Q000187:drug effects; D056804:Biofuels / Q000032:analysis; D019149:Bioreactors / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D012722:Sewage / Q000382:microbiology*; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods*; D018508:Water Purification
D000468:Alkalies; D056804:Biofuels; D012722:Sewage; D000641:Ammonia
Anaerobic digestion; Design of experiments (DOE); Primary sludge; Sludge management; Waste activated sludge