Hybrid Treatment Process of using MIEX and High Performance Composite Coagulant for DOM and Bromide Removal

Abstract

Dissolved organic matter (DOM) and bromide, two primary precursors of disinfection by-products, cannot be effectively removed by conventional coagulation processes. Alternative methods are required to ensure the safety of drinking water. The effectiveness of using magnetic ion exchange resin (MIEX) and high-performance coagulant (HPAC) in a hybrid process for the removal of turbidity, DOM, and bromide in raw water supplies was investigated. Results showed that a wide range of DOM, with different molecular weights (MWs) containing soluble microbial byproduct-like organic matters, aromatic protein, and fulvic/humic acid, was removed by MIEX in the two studied water sources. In addition, up to 91% of bromide was removed in bromide spiked raw waters. In comparison, HPAC coagulation did not effectively eliminate low MW or soluble microbial byproduct-like organic matters in raw water. The combined MIEX and HPAC process more significantly improved the performance of turbidity, DOM, and bromide removal than coagulation alone. With MIEX pretreatment, the requisite HPAC dosage was reduced by at least 67%.