Guest Seminar, Renzun Zhao NC A&T: Delineating the characteristics, transformation and water quality impacts of landfill leachate induced dissolved organic nitrogen

Delineating the characteristics, transformation and water quality impacts of landfill leachate induced dissolved organic nitrogen

Renzun Zhao, PhD, PE

Associate Professor

Civil, Architectural and Environmental Engineering Dept.

North Carolina A&T State University

Abstract:

Emerging research identifies Dissolved Organic Nitrogen (DON) from landfill leachates as a significant source of nitrogen pollution in water bodies. DON is categorized into proteinaceous DON and humic substances (HS)-derived DON, each affecting algal growth and nitrogen removal in wastewater treatment differently.

Our study explores the presence, transformation, and effects of DON in landfill leachates on algal growth across biological and physicochemical treatment processes. We examined treatment methods like Fenton Oxidation, which breaks down recalcitrant DON (rDON) into ammonium nitrogen, making it suitable for biological nitrogen removal (BNR). Granular Activated Carbon (GAC) treatment, on the other hand, removes pollutants broadly from landfill leachate and municipal wastewater, offering wide pollution control. Additionally, our findings on Ultraviolet (UV) radiation show its dual effect on rDON: it decomposes rDON, enhancing algal growth, but can also damage algal DNA, inhibiting growth.

These insights aim to refine pollution management and inform environmental regulation for nitrogen control. By addressing DON from landfill leachates, our research contributes to advancing water treatment practices and protecting aquatic ecosystems from nitrogen pollution.

Keywords: Refractory Dissolved Organic Nitrogen (rDON), Landfill Leachate, Algal Growth, Fenton Oxidation, Granular Activated Carbon (GAC), UV radiation.