Investigating Low Temperature Dry Anaerobic Digestion of Nitrogen Rich Organic Feedstock

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Livestock manure management is an important environmental and social challenge. It negatively impacts the livestock industry through release of greenhouse gas emissions, odor, pathogens, and contamination of surface and ground water. However, manure could be treated by anaerobic digestion (AD) which addresses the aforementioned negative impacts and generate biofuel. This research is to investigate and develop a low temperature dry AD of Nitrogen (N)-rich manure (N-rich LTDAD) as a biotechnology to treat swine and poultry manure and produce methane at the novel combination of conditions (low temperature, high solids, and high N-loading). While it provides a technical and social solution, it will generate fundamental knowledge regarding the kinetics and microbial dynamics during adaptation to the new conditions. The objectives of this research is to develop LTDAD as an environmentally-sound, cost-effective and easy-to-use biotechnology to treat N-rich swine and poultry manure, elucidate its adaptation, kinetics, and microbial dynamics. It aims to: 1- fill the gap in our understanding on the microbial community changes during adaptation to low temperature, high solids, and high N-loading; 2- assess adaptation strategies and determine a start-up adaptation strategy; 3- elucidate the effects of biochar on the kinetics, microbial dynamics, and physiological changes in the culture during adaptation. It also assesses the effect of adaptation time to high ammonia levels on the performance and stability of LTDAD under increasing organic loading rate, increasing N-loading rate, increasing solid content, decreasing inoculum-to-substrate ratio, and decreasing treatment duration. It will improve our understanding of the microbiological/structural and physiological adaptation-induced changes using cell wall membrane phospholipid biomarkers and correlate them with the results of molecular biology methods. In a long term, the program aims to scale-up the laboratory SBR by 1000x, evaluate its stability and performance, and find whether the adaptation-induced changes in lipids profile affect ammonia diffusivity through the cell wall. This research's output will improve the farming sector and provide environmental, social, economic, health and climatic benefits. The improved knowledge of N-rich LTDAD gained from this research could benefit other N-rich wastes such as slaughterhouses, meat, fish, food processing, and animal farm mortalities. It will also will bring in socioeconomic benefits through its training and outreach program. It will train 8 students and develop them professionally, and support an outreach program to engage high school students and teachers from the local community to promote environmental biotechnology in Newfoundland. This research will be integrated with an on-going imitative, by the applicant, of an educational farm at the Lester's Dairy Farm in St. John's, NL with a focus on livestock and agriculture waste management and bioenergy.