AWWA ACE61611

The objectives of this study are to investigate the effects of pH, hydraulic retention time (HRT), and zerovalent iron (ZVI) dosages on the removal of nitrate in single-column system and two-column system. Materials and experimental methods included: synthetic nitrate-containing input water was prepared using the laboratory tap water spiked with sodium nitrate; ZVI powder (Acros Organics Co., USA) with nominal particle size of 325 mesh (40 µm) was used as received; and, concentrations of nitrate, nitrite, and ammonium were measured colorimetrically according to the methods 4500 listed in the 20th edition of Standard Methods using a UV-Vis spectrophotometer (Helios beta, Thermo Electron Corporation).