Municipal Solid Waste Leachate Organic Matter Generation and Removal

The University Of Central Florida Board Of Trustees, Orlando FL

Investigators

Abstract

CBET-1438416 This research addresses the management of a particularly challenging constituent of leachate from landfills, leachate organic matter (LOM), with the goal of reducing the long-term risks and costs associated with landfill operation. Through this research, for the first time, information will be provided that may lead to the control of LOM that passes through biological treatment systems. Further, by providing information regarding the potential for natural systems to assimilate low level contributions of non-biodegradable LOM from closed landfills, society may be relieved from long-term financial burdens of landfill post-closure care (PCC). A better understanding of LOM fate and behavior can provide regulators with the information needed to confidently approve reducing or terminating landfill PCC. The proposed research has clear societal benefits associated with reduced cost and risk of landfills, a greater understanding of leachate discharges to the environment, and more sustainable solid waste management. This research will examine the chemical nature of leachate organic matter (LOM) to better understand the humification of landfilled waste and the fate of discharged LOM to the environment after in situ landfill treatment, co-treatment at a Waste Water Treatment Plant, or on-site biological treatment. The hypothesis is that recalcitrant LOM production is associated with specific components of solid waste, therefore the avoidance of these components in future landfills could result in enhanced leachate treatability and reduced treatment cost. It is further hypothesized that the consequences of discharging LOM in treated leachate from existing landfills can be attenuated through passive sunlight-driven photolysis. Specific research questions to be addressed include the following: (1) which waste components contribute to recalcitrant LOM; (2) can we use advanced characterization tools to better understand the potential for LOM biodegradation, photolysis, or contaminant transport; and (3) what is the fate of recalcitrant LOM in aquatic environments (e.g., wetlands and surface waters), with a focus on photolysis? This research will be accomplished by well characterizing LOM, conducting microcosms examining the evolution of LOM from waste components, and evaluating LOM photolysis of leachate samples irradiated by natural sunlight and a solar simulator. The broader impacts of this proposed research also include the advancement of understanding of chemistry and photochemistry of organic matter. The proposed research is a multidisciplinary project that involves a diverse group of female researchers, bridging environmental engineering and physical science fields and impacting multiple areas of the scientific community. The doctoral researcher assigned to this project is a female minority student, contributing to diversity in the science and engineering workforce. Outreach to art and design students through UCFSTEAM (Science, Technology, Engineering, Art, and Mathematics) activities will also provide broader impacts. Researcher involvement with K-16 students through school visitations provides an opportunity to increase STEM understanding.