can be made of mild steel or any material suitable for transporting fly ash entrained in air or exhaust gas the plate 16 is made of hardened or mild steel and the spikes or wires are made of hardened steel to resist abrasion the metal structure could be placed directly in the gas flow as illustrated in fig1 or it could be located behind a baffle protected flow zone to reduce abrasion by ash particles fig7 the baffle would be made of an abrasion resistant material such as a ceramic a number of variations to this basic concept are possible first the insulated metal structures do not have to be plates any shape with a large surface area will do however there must be a sharp spike somewhere on the insulated metal structure in addition the sharp spikes can take many different forms they can for example be fine wires finally if the charge on the fly ash particles is not high enough to produce an electric field at the tip of the spikes which is high enough to produce a corona discharge the field can be increased by connecting the metal structure to an external voltage supply that will raise the electric field on the metal structure the inventor also envisions his ozone generating device to be mounted in a non metallic non conducting pipe or tube in such an installation the metallic sharp tipped component mounted on the metal plate or surface does not in turn have to be mounted on an insulator since the non metallic pipe is non conducting accordingly the metallic sharp tipped component mounted on a metal surface is placed in the non metallic pipe to produce the corona effect to produce ozone to.