REMOVAL OF IRON AND MANGANESE FROM WATER WITH A HIGH ORGANIC CARBON LOADING. PART Ⅱ: THE EFFECT OF VARIOUS ADSORBENTS AND NANOFILTRATION MEMBRANES

摘要

This paper describes the second part of an investigation into the removal of iron and manganese from water with ahigh dissolved organic carbon (DOC) loading. This investigation focused on the use of ferrichloride as coagulant in conjunction with hydrogen peroxide as an oxidant and different physical treatment processes, such as adsorption and nanofiltration, to reduce dissolved iron and manganese in water with a high DOC loading. It was found that nanofiltration employing H_2O_2 is the only treatment capable of producing drinking water within the set requirements of the treatment facility. Both fly ash and powdered activated carbon (PAC) used as adsorbents yielded a low percentage removal of DOC, while all the treatment methods evaluated accomplished high removals of the metallic ions Fe(Ⅱ) and Mn(Ⅱ). From the results a staggered treatment approach is recommended to obtain the best results at the lowest cost.