In the last set of postings to this blog, we have discussed how ozone is made and used in water treatment. We will now start a series of postings on applications of ozone in water treatment. We begin here with a brief overview of overview of ozone water treatment applications.
In Europe, ozone has been used in the treatment of drinking water for over 100 years. Since that time it has found uses in a wide variety of other applications food processing, beverages, textiles, aquaculture, aquariums, pools, water features, industrial wastewater, municipal wastewater, cooling towers among many others.
Ozone has a number of benefits in water treatment which have created the applications noted above including disinfection, flocculation, oxidation and increasing dissolved oxygen levels in water. Ozone often is employed when multiple water treatment challenges are present at the same time. Like other water treatment technologies, such as filtration, it is another tool in the tool box for engineers and operators to use improve water quality. In fact, in drinking water, ozone is being used in conjunction with other water treatment technologies to create multiple barriers to pathogen reaching the public.
Ozone is a powerful and fast acting disinfectant that has been proven to inactivate viruses, bacteria and protozoa. In treating giardia lamblia for example it is 1,000 time more effective than chlorine. It is also less sensitive to the pH of water with respect to its disinfection capabilities.
Ozone is also a powerful oxidant that can be used to remove hydrogen sulfide, iron and manganese, color, taste, odor and disinfection byproduct precursors from the water.
Ozone has also been shown to act like a micro flocculant. Many water treatment plants that have switched to ozone have seen a reduction in the chemicals used for coagulation and flocculation. These reductions have been in the range of 20-50%.
In subsequent postings we will look at the various applications for ozone in water treatment in more detail.