Ozone is formed when an electric spark is passed through oxygen, and causes a detectable odor near electrical machinery. The commercial method of preparation consists of passing cold, dry oxygen through a silent electrical discharge.
Ozone is much more active chemically than ordinary oxygen and is a better oxidizing agent.
After the ozone is injected into the reaction tank the water passes through an iron and manganese removal filter. Periodically the filter is backwashed. At the membrane treatment system, water pressure is increased before entering the membranes. From time to time the R.O. membranes need to be cleaned. This is done with a solution of sulfuric acid.