Thermophilic and hyper-thermophilic co-digestion of waste activated sludge and fat, oil and grease: Evaluating and modeling methane production.
Renewable energy and clean environment are two crucial requirements for our modern world. Low cost, energy production and limited environmental impact make anaerobic digestion (AD) a promising technology for stabilizing organic waste and in particular, sewage waste. The anaerobic co-digestion of thickened waste activated sludge (TWAS) and sewage treatment plant trapped fat, oil and grease (FOG) using different FOG-TWAS mixtures (20, 40, 60 and 80% of FOG based on total volatile solids (TVS)) were investigated in this study using both thermophilic (55 ± 1 °C) and two stages hyper-thermophilic/thermophilic (70 ± 1 °C and 55 ± 1 °C) anaerobic co-digestion. The hyper-thermophilic co-digestion approach as a part of the co-digestion process has been shown to be very useful in improving the methane production. During hyper-thermophilic biochemical methane potential (BMP) assay testing the sample with 60% FOG (based on TVS) has been shown to significantly increase the maximum methane production to 673.1 ± 14.0 ml of methane as compared to 316.4 ± 14.3 ml of methane for the control sample. This represents a 112.7% increase in methane production compared to the control sample considered in this paper. These results signify the importance of hyper-thermophilic digestion to the co-digestion of TWAS-FOG field.
Department of Civil Engineering, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada. Electronic address: raniaqaralleh@yahoo.com.
Rania Mona
RM
Alqaralleh
Department of Civil Engineering, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
Kevin
K
Kennedy
Department of Civil Engineering, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
Robert
R
Delatolla
Department of Civil Engineering, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
Majid
M
Sartaj
D000693:Anaerobiosis; D056804:Biofuels / Q000032:analysis*; D019149:Bioreactors / Q000382:microbiology*; D005223:Fats / Q000378:metabolism*; D008697:Methane / Q000032:analysis / Q000378:metabolism*; D009821:Oils / Q000378:metabolism*; D059205:Renewable Energy; D012722:Sewage / Q000382:microbiology*; D018508:Water Purification / Q000379:methods*
D056804:Biofuels; D005223:Fats; D009821:Oils; D012722:Sewage; D008697:Methane
Anaerobic co-digestion; FOG; Hyper-thermophilic; Methane yield; Non-linear regression; Renewable energy; Thermophilic