Engineering Commons^™

Phosphate And Thermal Stabilization Of Heavy Metals In Dredged Sediments, Peter Kuria Ndiba

Dissertations

Treatment and reuse of dredged harbor sediments in construction as an alternative to disposal reduces costs and conserves resources. This research focused on leachability of metal contaminants subsequent to phosphate addition and thermal treatment at 700 °C. X- ray absorption spectroscopy (XAS) in combination with principal component analysis, target transformation, and linear combination revealed that in the untreated sediments Zn precipitated as the relatively soluble smithsonite (ZnCO₃) (67%) and adsorbed to hydrous iron oxides (15%) and hydrous manganese oxides (18%). Phosphate addition and calcination resulted in sparingly soluble phases, hopeite (Zn₃₍PO₄)₂.4H_{2 …}

Characterization Of Natural Organic Matter And Precursors To Trihalomethanes Using Spectral Flourescence Signatures, Krit Punburananon

Dissertations

Disinfection is an essential process to kill pathogens (i.e., disease causing organisms) in source water during the production of drinking water. Chlorine is most widely used disinfectant because it is effective, affordable, and also provides chlorine residual to ensure that the water is safe through the distribution system. Nonetheless, chlorine reacts with Natural Organic Matter (NOM) and forms potentially carcinogenic Disinfection By-products (DBPs). The major chlorination DBPs are dominantly Trihalomethanes (THMs). However, not all organic compounds are equally reactive to THMs formation.

NOM in water samples collected from the Delaware & Raritan Canal and its tributaries (Central New Jersey) was …