This research study focused on evaluating the organic matter (OM) phase-transformation
behavior when using metal-salt coagulants to treat source waters containing appreciable dissolved organic matter (DOM)
concentrations. The OM phase-transformation protocol used here consists of three OM size
categories - dissolved, colloidal, and particulate - operationally defined by filtration techniques.
Particulate organic matter,
formed by interaction of DOM with aluminum or iron coagulants, was defined as the fraction of
OM retained by a 1 µm glass-fiber (GF) filter. The fraction of OM that passed a 1 µm GF filter
but was retained by a 30 kiloDalton (kDa) ultrafiltration (UF) membrane was termed colloidal
organic matter, whereas any organics that passed a 30 kDa UF membrane following coagulation
were considered dissolved organic matter. Colloid formation during coagulation of drinking water may provide a means to achieve
acceptable OM and turbidity removal at lower coagulant dosages, provided that the colloidal
matter formed is amenable to solid-liquid separation by subsequent filtration processes. The
primary objective of this research was to evaluate how coagulant type and dose, as well as water
chemistry parameters including pH, turbidity, temperature, and DOM concentration, affect the
formation of colloidal matter during coagulation of source waters with alum and ferric sulfate.
Additionally, the relative performance of these coagulants was evaluated and the phase
transformation of DOM and coagulant metal compared for selected coagulation conditions. Includes 27 references, table, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 440 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 18 |
| Published : | 06/17/2005 |
