Ozone: Both Mature and New

Abstract

There are those who state that ozone is now a mature technology. This impression is most likely based on the well-established use of ozone for drinking water purification. Ozone is very effective in improving taste and odor, helping to eliminate the formation of trihalomethanes, provide disinfection and help filtration performance. Ozone has been used for disinfection of drinking water for large municipalities for more than 50 years. This is definitely mature technology. However, even with drinking water treatment, there have been new developments with ozone, particularly when considering ozone mass transfer. Historically water treatment plants used porous plate diffusers and many still do today. In the interest of saving space and reducing capital, operational and maintenance costs, sidestream venturi injectors (SVIs) have been developed to introduce ozone into water. Over the past several years this process has been optimized using computational fluid dynamics to help in determine the optimum injection nozzle locations for a particular process. Today, a large percentage of new drinking waters are using SVIs. Another significant advance has been the use of static mixers to improve the ozone dissolution. Many remember the old air-fed ozone generators equipped with elaborate air-drying systems. These were the original workhorse generators of the ozone industry. Engineers and scientists have since developed new power conversion technologies and dielectrics tailored to oxygen feed gas resulting in considerable improvement in efficiency and reduction of space. We continue to see incremental improvement in ozone generator performance and the use of very reliable efficient power conversion equipment. Scientists are now demonstrating how a Xenon Excimer can be used to produce very high concentration ozone at an economical power consumption. In the early days of ozone, scientists discovered advanced oxidation where ozone combined with hydrogen peroxide formed free radicals which could quickly oxidize difficult contaminants. This led to the concept of catalytic ozonation where ozone combined with a solid catalyst could provide a similar benefit. This new technology is being heavily researched and may soon lead to commercial processes. Ozone was considered and used for wastewater treatment in the 1980s but fell out of favor due to operating costs and possibly misapplication. Today, there is emphasis on water reuse – reclaiming wastewater for use as potable water. Ozone combined with biological filtration has been found to be an newly effective process to accomplish this, particularly in areas where concentrate from reverse osmosis/ultrafiltration plants cannot be effectively disposed. IN 1997 the FDA approved ozone as GRAS for foods. In 2001 ozone was approved as an antimicrobial additive for direct contact with foods. Research on how to apply this newly approved technology began in earnest and continues today and ozone is tested on new food products for its applicability. OS&E published a special issue in early 2022 on the use of ozone for food preservation. One of the newest developments is the demonstration that ozone can be an effective tool in fighting COVID19. Ozone is a very effective surface sanitizer and is effective in inactivation of the COVID virus. Surfaces can be exposed to an ozone gas or sprayed with water containing ozone. Ozone: Science & Engineering (OS&E) has published several articles on COVID and its inactivation. Yes, it is true that ozone has been around for many years but it also true that the technology continues to get better. OS&E has been and continues to be the premier journal to highlight research on these new and improved technologies. Your membership to the International Ozone Association (IOA) ensures that the IOA can continue this mission. Thank you for your support as an IOA member. There’s a lot of “new” in ozone today and we expect for the technology to stay “new.”