How is Ozone Made? – 2nd Edition

Posted by Joel Leusink on November 28, 2011 under How is Ozone Made?, Ozone Generators | Read the First Comment

About a week ago we posted about how ozone is made.  That original post gave the fundamentals of how ozone is produced in nature and the basics of how ozone is produced within ozone generators, both UV ozone generators and corona discharge ozone generators.  It was pointed out then that most (almost every) industrial ozone generator uses corona discharge to produce ozone.  This 2nd installment is dedicated to informing you the reader about ozone generation from corona discharge.

How is ozone made?

The fundamentals are simple.  A spark (corona discharge) is used to split the diatomic oxygen molecule into valant oxygen atoms.  These oxygen atoms have a negative charge and will bond quickly with another oxygen molecule to produce ozone!  For each split oxygen molecule 2 ozone molecules are produced.

Ozone Generation from Corona Discharge

Ozone formation

A power supply is used to produce an electrical discharge across a dielectric, and an air gap.  The dielectric is used to diffuse the discharge across a large area as opposed to single point like a normal spark.  The oxygen molecules passing through the air gap are exposed to the electrical discharge and are split into ozone (at least that is the hope).  A great deal of heat is generated from this process and is removed from the electrodes as shown.

Corona Discharge Tube

ozone production

This image shows a more complete picture of a very typical ozone generation corona cell.  The dielectric is a tube allowing the air gap to flow around the outside of the dielectric, with the electrode around the outside.  This allows heat to be dissipated to the outside of the electrode efficiently.

This video shows a great example of ozone production from corona discharge.

There are three main factors when generating ozone from corona discharge:

  • Power supply
    • Operating voltage
    • Operating frequency
  • Dielectric
    • Glass
    • Ceramic
    • Mica
    • Quartz
  • Corona Cell
    • Tube – cylindrical style
    • Flat plate

When generating ozone from corona discharge there are a few factors that will affect performance that must be evaluated.

  • Cooling of the corona cell
    • Water cooled
    • Air cooled
  • Feed gas
    • Oxygen
    • Dry Air

I will try to cover some of these fundamentals and why one may be better than another for your specific application in future installments of “how ozone is made

How is Ozone Made?

Posted by Joel Leusink on November 14, 2011 under How is Ozone Made?, Ozone Generators | 2 Comments to Read

Ozone is produced naturally through sparks and UV-Light, ozone is also produced commercially for many uses.  This will outline a few methods ozone is produced.

 

Lighting (Corona Discharge)

Ozone is Produced Naturally from Lightening During Thunderstorms.

Ultra-violet (UV) Light

Ozone is Produced Naturally from UV Light from the Sun

These same methods of ozone generations can be used commercially for industrial ozone applications.  Great advancements have been made in the ozone industry to produce ozone more reliably and efficiently.

Ozone Production from Corona Discharge

Corona Discharge

Oxygen flowing between an electrode and cathode produces ozone from a spark, more commonly referred to as Corona Discharge.

Ozone Production from UV Light

Ozone Production from Ultra Violet Light

Ozone can be produced from a UV light tuned to the proper wavelength inside an enclosed chamber.

Ozone can also be produced directly in water using an electrolytic cell.  This method uses a current within the water to split the oxygen and hydrogen atoms, then converts the oxygen directly into ozone.  This is a fairly new commercial ozone generation method that may show great promise in the future.  At this time, this application has very limited application.

Commercial Ozone Generation

  • Corona Discharge (electrical discharge field)
    • High voltage spark at medium to high frequencies
    • Creates ozone at medium – high concentrations (up to 22%)
    • Most commonly used
  • UV Ozone Generation (photochemical)
    • Low concentration ( max 2% concentration)
    • Small ozone outputs
  • Electrolytic
    • Currently only small outputs
    • Ultra pure water is necessary

The most common method of ozone generation is corona discharge.  Due to the low operation costs, and improved reliability this will be the main method of ozone generation for many years to come, for more information on ozone generation watch for future installments of “How Ozone is Made