Ozone in the News

SCRUTINIZING OZONE TREATMENT OF DRINKING WATER Ozone in the stratosphere acts as a sunscreen,...but in drinking water ...ozone makes an effective disinfectant and purifier. Ozone treatment also avoids creation of trihalomethanes (THMs), the harmful by-products formed in the more common chlorine treatment of water. The products formed during ozonation appear to be harmless... In the United States and Canada, the number of ozonation plants increased from 28 to almost 70 between 1977 and 1984. ENVIRONMENTAL SCIENCE & TECHNOLOGY

Ozone generators are used in some systems to produce small quantities of the gas which is a very strong oxidizing agent, and is effective in killing bacteria with short exposure times. Ozone is also effective in oxidizing organic matter, iron and manganese, and produces no tastes and odors. REEVES JOURNAL

OZONATION IS WAVE OF FUTURE FOR DRINKING WATER Ozone is looking like the chemical of choice to replace chlorine in drinking water treatment plants as EPA's new surface water disinfection rules under the amended 1986 Safe Drinking Water Act (SDWA) come into effect over the next couple of years. Rice has predicted that 75% of all U.S. surface water treatment plants directly influenced by surface waters will install ozone by 1995. Montgomery is currently working on a pilot plant in LaVerne, Calif. for the Metropolitan Water District of Southern California. It supplies half of Southern California's water needs and has been studying ozone a treatment option for the last two years, primarily in response to the new EPA rules. Drinking water has been treated with ozone in Europe since 1906. The first plant was in Nice, France. Today, Europe has 3,000 ozonation facilities, said consultant Rip Rice. Research into chlorine alternatives in the United States began in 1974 when that chemical was discovered to have harmful residues, said the EPA's Director of Drinking Water Standards Joseph Cotruvo. Ozone has a short life and must be generated on site. ENVIRONMENTAL BUSINESS JOURNAL

"Chlorine produces byproducts such as THMs that can be harmful to human health. The need for THM (Trihalomethane) control has forced water utilities to search for appropriate substitutes... Ozone and chlorine dioxide are being used presently at various facilities." "In tests in which ozone has been compared with chlorine, ozone has been shown to be superior as a coagulant..." William H. Glaze UCLA Professor of Public Health

During the past two years the professional water treatment trade press has devoted considerable space and attention to the technological aspects of ozonation as a purification and oxidation technique for residential point-of-entry/point of use applications. "Folks usually won't call a treatment company until they've decided they just can't live with their problems any longer. That often means their water is so bad it's beyond the scope of the type of treatment devices available...But ozone, combined with appropriate filtration and other system components tailored to the specific problem, permits us to tackle water chemistries that we might have avoided before." Durham typically uses the ozone system to treat coliform bacteria, iron, iron bacteria, hydrogen sulfide, taste, color and odor. "we've seen results such a 33 parts per million iron reduced to non-detectable and effluent of bottled water quality where taste and smell have been the problem." "Ozone generally makes other equipment perform better..." WATER CONDITIONING & PURIFICATION

Seraydarian also said people who get water from private wells should be concerned, and not only with toxics. A study of private wells in the county revealed 36 percent of those are contaminated with coliform bacteria. Carbon filters on taps can be home to bacteria. Water softeners should be hooked up to hot water only. That way, cold water used for drinking is free from the high levels of sodium used to soften the water. LOS GATOS TIMES OBSERVER

"We have a number of water store operators who use ozone not only for purification of their holding tanks...but also as a means of insuring that any potentially contaminated bottles their customers may bring in will be disinfected." Another potentially important ozone application is pre-treatment for R.O. systems to reduce biofouling of the membranes. ...reports from such industry authorities as Robert Slovak of Water Factory Systems have stated that ozone is the best treatment available for sanitizing holding tanks and preventing taste and odor from occurring during storage. "Because ozone will oxidize iron, manganese and hydrogen sulfide, the overall load on the softener is greatly reduced," Long added. WATER CONDITIONING & PURIFICATION

Ozone is only partially soluble in water, as a rule of thumb, about 13 times the solubility of oxygen. As a result, applying ozone to water involves gas/liquid contacting. Of those materials readily available for water treatment, ozone is the most powerful, having an oxidation potential about 1.5 times higher than that of chlorine, and 20% higher than pure hydrogen peroxide. OZONE FOR DRINKING WATER TREATMENT

CHLORINE'S OUT, OZONE'S IN AS PURIFIER OF WATER ."..Adding chlorine to water is not a healthy practice... For years no one knew that people were getting small doses of THMs every time they brushed their teeth or made lemonade... The ozone gas, which smells like watermelons, disinfects as well as chlorine does. It is more expensive. Europeans pay much more for their water than Americans. But , unlike chlorine, ozone disappears into the air within 24 hours, leaving behind no toxic residuals... The two year old, $106 million plant in Sylmar, Los Anglels, is one of the largest in the world that disinfects with ozone... So far, nothing alarming has been found in the product of the plant called 'one of the best in the world'." LOS ANGELES HERALD EXAMINER