The apparatus for producing a desired quantity of ozone uses a flow of air in which a corona discharge utilizes high voltage to produce sparks. This apparatus includes a source of high voltage and the spark is produced when metal or conducting edge portions of the blades are moved in way of spaced conductors carried in a tubular confine. The blades are carried as an assembly which may be rotated by a flow of air. The flow of air and the turning of the assembly maintains the blades in a cooled condition so that unwanted burning of the edges of the blades does not occur. The corona discharged ozone may be used in swimming pools, or as an air purifier or dust eliminator. The ozone, when used in a closed building, will utilize a timer so an excess of ozone is not produced. The rotating of the bladed member is preferably by the flow of air, said volume of air flow regulates the speed of rotation.