Ozone Facts

Why use Ozone (O₃)?

• The strongest single oxidizing agent available - 152% stronger than chlorine over broad pH range
• On-site generation - no transportation, handling or storage of hazardous compounds
• Environmentally compatible operation
• No added taste or odor
• No irritation to skin, ears and nose when dissolved in water
• Simplified water chemistry by reverting to oxygen
• The pH neutral chemical makeup does not affect the pH balance of water like traditional chemicals
• Reduction of chlorine or bromine consumption to a minimum, saving money on maintenance and material handling
• No THM (Trihalomethane) formation
• Bacteria free water
• Potential extension of food products' life
• Improved product quality
• Possible prevention in the need for Risk Management Plans
• Possible prevention in the need to report for Title III

For more information about the benefits of ozone in regards to a specific application, check out the information in each business unit listed under Products/Services.

Application Experience with Ozone (O₃)

• Aquaculture
• Barrel Washing (Wineries)
• Clean-in-place (Food processing & Wineries)
• Color Removal
• Cooling Towers
• De-ionized Water
• Etchant Rejuvenation
• Flume Treatment (Food)
• Fume Scrubbers
• Hydroponics
• Groundwater Remediation
• Industrial Processes
• Mammal Water Disinfection
• Microbiological Control
• Odor Control
• Phenol Reduction
• Process Waters
• Recreational Water
• Sanitation
• Soil Remediation
• Spray Washing (Food)
• Taste Control

What is Ozone (O₃)?
Background
Ozone is triatomic oxygen. It is distinguishable by a characteristic odor, first reported by Dutch chemist Martinus Van Marum in 1785, in the vicinity of an electrical discharge. In 1840, Christian Shonbein identified this characteristic odor as a previously unidentified compound. He named it ozone after the Greek word ozein, meaning "to smell.” The identity and structure of this compound was confirmed in 1867 as triatomic oxygen.

Chemical Properties
The three atoms of oxygen that make up one molecule of ozone are nearly the shape of an equilateral triangle. The electrical bonding between each oxygen molecule is achieved by sharing six electrons, two of which resonate between all three atoms. It is these electrons, which participate in the electrophillic attack on many substances during the oxidation process.

Ozone is the most powerful known oxidizing agent that can be used on a practical scale for treatment applications. For example, the comparative oxidizing strengths of ozone, chlorine, and chlorine dioxide are 2.07, 1.36, and 1.275 volts versus hydrogen, respectively.

Ozone is fairly stable in cool, dry air and has a half-life of several hours to several days at low concentration based on a variety of factors such as temperature, pressure and pH. In water, however, ozone’s half-life is instantaneous to several hours in soil, due to low temperature. Because ozone is very reactive, ozone can oxidize material between 10 to 1000 times faster than most oxidants used. In some instances of organic oxidation, the material can be completely oxidized to carbon dioxide and water.

Pure ozone is approximately 12.5 times more soluble in water than oxygen. Ozone treatment systems traditionally inject air containing 1-6% ozone concentrations by weight into water. At these levels the maximum solubility of ozone is between 2 and 6 ppm, respectively, depending primarily on temperature and pressure.

Ozone Production
Because ozone has such a short half-life, it cannot be stored. Instead, it must be generated on site and used immediately. Electrical generation utilizes the most practical and safe method for large scale applications of ozone. The most widely used electrical generation technology is the corona discharge method. A corona discharge generator accelerates electrons, providing sufficient energy to split the oxygen-oxygen double bond upon impact with another oxygen molecule. The two oxygen atoms produced by the collision react with other diatomic oxygen molecules to form ozone.

When enough high energy electrons bombard gas molecules so they are ionized, a light emitting gaseous plasma is formed. This is commonly referred to as a corona. In practice, corona discharge generators can produce ozone concentrations of 1-2% using air and 3-12% using oxygen.

Properly designed corona discharge generators utilize higher frequencies (typically 300-1000 Hz) are favored because greater ozone production can be achieved with less electrode surface area and less electrical consumption.

The corona discharge device can be fabricated and configured in many different ways. The basic purpose is to maximize ozone production and concentration by generating a corona between two electrode surfaces. Corona discharge units properly designed and containing modern safety features can produce ozone reliably, efficiently, and safely for many years.