Abstract by Anne Bennion
Chemistry and Biochemistry
Caldicellulosiruptor bescii growth and viability during pretreatment of waste activated sludge increases methane fuel production of anaerobic digestion
Wastewater treatment not only protects freshwater resources, but also constitutes a potential source of renewable energy. Waste activated sludge (WAS) from aerobic sewage treatment can be converted to biogas through anaerobic digestion (AD) to reduce high costs of disposal. Chemical pretreatment of WAS increases methane production, but proves costly and inefficient, and without pretreatment methane yield of AD is often low. Biological pretreatment of WAS with cellulolytic anaerobe Caldicellulosiruptor bescii increases methane conversion and production. Using spectrophotometry we measured C. bescii growth on WAS over 48 hours and using flow cytometry investigated the viability of C. bescii in less than optimal growth conditions. The growth yield of C. bescii on the bacterial biomass in WAS proved comparable to standard culture medias. C. bescii survived exposure to oxygen when brought from 75°C to 25°C and revived after returning to optimal growth conditions. C. bescii growth and robustness make biological pretreatment with C. bescii a viable method to better utilize WAS as a feedstock for biopower applications.