Natural Organic Matter (NOM) Removal by Coagulation and Adsorption

Abstract

Natural organic matter (NOM) is defined as a complex matrix of organic materials in all natural waters. NOM affects significantly many aspects of water treatment, including formation of disinfection by-products (DBPs) resulting from reactions between NOM and disinfectant, the performance of the unit processes, application of water treatment chemicals and biological stability of water. The amount, character and properties of NOM differ considerably in waters of different origins and depend on the biogeochemical cycles of the surrounding environments. Trihalomethanes (THMs) and haloacetic acids (HAAs) which are the first two major classes of DBPs, have diverse toxicological effects. Therefore it is important that NOM removal from surface waters.

In this study, NOM removal from Altinapa Dam Water (ADW) was investigated by conventional coagulation and adsorption. TOC removal was obtained as 45% for aluminium sulphate (alum) and poly-aluminium chloride (PACl) coagulation/flocculation process at 2 mg/L TOC concentration. TOC removal efficiencies for adsorption with different adsorbents were determined approximately 50%.  Total THMs (TTHMs) precursor removal was provided with PACl and total HAAs (THAAs) precursor removal was provided with alum and clay.