Origin and Elimination of Tastes and Odors in Water Treatment Systems

Abstract

This chapter discusses the remedial actions which can be taken at the three different levels involved in the generation of taste and odor problems, the resource, the water treatment plant and the distribution system. A general approach methodology to cope efficiently with taste and odor problems is described. The section dealing with treatment at the resource level primarily discusses reservoir management practices necessary for controling problems arising from algal and microbial metabolites. The next section deals extensively with the beneficial and detrimental effects associated with each drinking water treatment step including clarification, aeration, oxidation with potassium permanganate and ozone, disinfection with chlorine and chlorine dioxide, activated carbon adsorption and biological treatments. The effects of these processes on the elimination of algal toxins occasionally associated with taste and odor problems generated by blue-green algae, are also discussed. A case study describing the behavior of taste and odor descriptors determined by flavor profile analysis and specific volatile organics during the treatment of an artificially recharged ground water, illustrates the global methodology required to understand tastes and odors originating from complex mixtures of trace organics.