ABSTRACT
Ozone is used in three ways: as a biocide, as a classical oxidant, and as a pretreatment for improving the performance of subsequent processes. The ability of ozone to act as a disinfectant and classical oxidant has long been known. Ozone can also be used at any intermediate point if it is needed to control growths within the plant. The addition of ozone at multiple locations within water treatment plants is thus a natural outgrowth of its diverse applications. The increase in the use of ozone worldwide is partly due to the pioneering work of a small number of engineers and scientists. The chapter reviews the literature that deals with reduced iron and manganese removal, emphasizing studies utilizing ozone. The presence of high levels of bicarbonate can modify consumption of oxidant such that less ozone is required. Perhaps the most convincing link between raw water quality and coagulating effects of ozone concern calcium hardness.
