Pretreatment of Waste Activated Sludge with Caldicellulosiruptor Bescii Increases Methane Production During Anaerobic Digestion
Location
Logan Golf & Country Club, Logan, UT
Start Date
3-26-2019 5:00 PM
End Date
3-26-2019 7:00 PM
Description
Wastewater treatment not only protects freshwater resources, but also constitutes a potential source for renewable energy. Waste activated sludge (WAS) from aerobic sewage treatment can be converted to biogas through anaerobic digestion (AD). The methane content, however, is often too low with a baseline of approximately 5-10% carbon conversion into methane. We investigated the effectiveness of pretreatment with hyperthermophilic anaerobe Caldicellulosiruptor bescii to enhance methane production and conversion. In a 30L pretreatment and 60L anaerobic digester vessel, C. bescii increased methane yield almost two-fold and increased methane conversion to upwards of 63% in only 72 hours. The pretreatment of WAS also allowed a dramatic reduction in the hydraulic retention time of AD from >20 days for untreated WAS, to 5-10 days for pretreated WAS. By increasing methane conversion, elevating the total biogas output, and decreasing processing time, biological pretreatment with C. bescii may prove WAS to be a feasible feedstock for biopower applications.
Pretreatment of Waste Activated Sludge with Caldicellulosiruptor Bescii Increases Methane Production During Anaerobic Digestion
Logan Golf & Country Club, Logan, UT
Wastewater treatment not only protects freshwater resources, but also constitutes a potential source for renewable energy. Waste activated sludge (WAS) from aerobic sewage treatment can be converted to biogas through anaerobic digestion (AD). The methane content, however, is often too low with a baseline of approximately 5-10% carbon conversion into methane. We investigated the effectiveness of pretreatment with hyperthermophilic anaerobe Caldicellulosiruptor bescii to enhance methane production and conversion. In a 30L pretreatment and 60L anaerobic digester vessel, C. bescii increased methane yield almost two-fold and increased methane conversion to upwards of 63% in only 72 hours. The pretreatment of WAS also allowed a dramatic reduction in the hydraulic retention time of AD from >20 days for untreated WAS, to 5-10 days for pretreated WAS. By increasing methane conversion, elevating the total biogas output, and decreasing processing time, biological pretreatment with C. bescii may prove WAS to be a feasible feedstock for biopower applications.