Odour Problems in Potable Water and its Treatment Options: a Review

Odours in potable waters are the major complaint repeated by customers worldwide. Water utilities have justified or ignored them, because, in most cases, the odorous waters satisfy all of the water laws and registration requirements. For customers however, odour is often the primary judgement of water quality. Odour problems are usually caused by Aqueous Organic Matter (AOM). Furthermore, the AOM can be produced as unexpected by-products (e.g. disinfection by-products) during water treatment processes. Hence, eliminating AOM during water treatment is one of the highest priorities in water utilities. Several investigations have been performed for the identification, characterization, treatment options, and treatability of the AOM. Unfortunately, these researchers have proved that the Conventional Potable Water Treatment (CPWT) processes, which consist of coagulation, sedimentation, rapid media filtration and disinfection, are not suitable for reducing the AOM concentration to a level low enough to alleviate odour problems. These researchers have also justified the introduction of advanced or alternative processes such as granular activated carbon bed adsorption, ozonation and membrane filtration for improving AOM removal. The goal of this review is to look at the research which has been done in this area and to find out the best available operations, in terms of AOM reduction, in current CPWT plants for minimizing odour, that can be performed easily and demand minimum budget and modification. For this purpose, options available such as enhanced coagulation, powdered activated carbon adsorption, oxidation and membrane filtration will be investigated and their efficiencies assessed in comparison with the performance of CPWT processes