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Ozone

Ozone is one of the best chemical oxidizers and maintains only a short-lived chemical residual.  Ozone systems are used as oxidizing systems to treat sulfur and iron as well as for continuous disinfection.

Ozone can be generated by corona arc discharge or ultraviolet light. Only corona arc is allowed for generating ozone for private water system disinfection in Ohio. Air is passed through a high-voltage electric field called a corona. Corona arc discharge creates ozone in a similar same way that lightning creates ozone naturally.  An air dryer should be added to help in the production of ozone.Ozone Disinfection System

It should be noted that many commercial ozone system use UV for creating ozone generation for oxidation. The UV light used to generate ozone is designed to work at a different frequency than UV light used for continuous disinfection only and has a more limited capability to disinfect water. Ultraviolet light does not produce a sufficient quantity of ozone for adequate continuous disinfection of private water systems. UV generates from 10 to 1000 times less ozone by weight than corona arc.

Ozone used for continuous disinfection in Ohio shall have sufficient ozone added to the water to satisfy the demand, and the CT value shall be no less than 0.6 at pH seven and 5 degrees Celsius (41 degrees F). Ozone must have a minimum detectable residual of 0.1 milligram per liter after six minutes of contact.

Mixing prior to contact for ozone can be achieved using a bubble diffuser and venturi nozzles.  A venturi basically squeezes that water and ozone together at the point of injection. Bubble diffusers work by emitting ozone through hundreds of bubbles beneath the waters surface.

Due to the strong oxidizing properties of ozone, components used in ozone systems must be capable of resisting corrosive. Ozone is considered a potential indoor air hazard and needs to be destroyed or vented to the outside.

Page Reviewed 12/09/2015