Ozone's growth in domestic drinking water treatment has been dramatic in Europe since the early 1900s and in North America for the past three decades. The many advantages of ozone as a multi-platform treatment technology are well documented, but an often overlooked aspect is ozonation as a cost saving method versus other technologies. Here are some examples:

Ozone as a flocculating agent results in rapid and enhanced microflocculation of raw waters. The net result can be an increase in plant filtration rates, decrease in size of filtration beds and lower chemical costs.

As a pure disinfectant, the higher oxidation potential of ozone versus chlorine results in reduced contact time, which can mean smaller contact chambers (footprint). In fully developed areas, where the cost of land is at a premium, the reduced space requirement is a tremendous savings.

Some pollutants can only be oxidized by ozone. Cryptosporidium parvum, for example, are very resistant to most chemical disinfectants but are economically and effectively destroyed by ozonation. Most other applicable methods act only as barriers to cysts but do not actually destroy them.

Ozone not only has a positive effect on COD removal by breaking down refractory compounds and making them biodegradable but also prolongs the service life of GAC. This feature alone makes ozone economically feasible when GAC is needed. Ozone can totally replace chlorine, chloramines or chlorine dioxide in the preoxidation and main oxidation stages. Although some form of chlorine residual is nearly always required in the distribution networks, ozone can drastically reduce its use, enhance the quality of the water and still be more economical than other oxidants.

With recent advancements in ozone generation technology, the cost of ozone from both capital and operating investment is less than half of what it was only seven years ago. As the cost of ownership goes down and application methods are optimized, ozone will continue to be at the forefront of desirable and economical drinking water treatment technologies. These savings have been demonstrated in many cities around the world, including Los Angeles, Orlando, Mexico City, Barcelona, Singapore, Paris, Shanghai and Zurich.