BIOLOGICAL PROCESSING OF AGRICULTURAL AND FOOD WASTES TO RECOVER ENERGY, NUTRIENTS AND WATER FOR SUSTAINABLE AGRICULTURAL PRODUCTION

Agricultural production requires large amounts of energy, fertilizers and water. The supply of energy, fertilizers and water for agricultural production is becoming a constraint to the food security and environmental sustainability. The agricultural production and food processing meanwhile generate substantial amounts of solid wastes and wastewater. Current practices of managing agricultural and food wastes can result in serious pollution of water and air. This project is to develop an integrated biological approach to efficiently and economically recover energy, nutrients and water from agricultural and food wastes for sustainable agricultural production. The biological process includes four main unit operations: (1) anaerobic digestion of different agricultural and food wastes, (2) activation of solid digested residues, (3) microalgae cultivation on digestion effluent, and (4) adsorption of residual nutrients in wastewater and CO2 in biogas onto activated carbon. The nutrients concentrated and supported on activated carbon will be used as a fertilizer. The CO2 captured on activated carbon will be used for algal cultivation. The project will establish scientific and engineering tools to optimize the four unit operations of the biological process, analyze the economics and evaluate the environmental impacts of the process for sustainable agricultural production. Introduction of a well-understood biological system developed by this project will improve the economies and sustainability of agricultural production by reducing waste treatment costs, generating additional revenues from the wastes, and supplying energy, nutrients and clean water for agricultural production in a sustainable way. This project is designated to address two national priorities of USDA-NIFA: sustainable energy and climate change. This project will also support the two research initiatives of School of Agriculture and Environmental Sciences at North Carolina A&T State University (NC A&T): (1) sustainable energy by producing energy and fertilizers from wastes, and (2) climate change by treating agricultural and food wastes. This project will provide comprehensive research opportunities for the students at NC A&T to conduct research for their dissertation, thesis, senior design, and undergraduate research experience. This project will strengthen our research capacity in the areas of bioenergy and wastes-to-energy.