Electrolytic ozonizer and method of decomposing ozone-containing waste gas using said ozonizer

An electrolytic ozonizer comprising:

• an electrolytic cell in which oxygen and ozone are evolved in an anode compartment by electrolysis of water, and hydrogen is evolved in a cathode compartment, including means for separating the evolved oxygen and ozone gas from the water electrolyte and means for separating the evolved hydrogen gas from the water electrolyte;
• a waste gas decomposing section being connected to said anode compartment of said electrolytic cell and being connected to said cathode compartment, wherein said waste gas decomposing section comprises a hollow member filled with a hydrogen conversion catalyst, said hollow member comprises a conduit for passage of waste gas, and said conduit penetrates said hollow member transversely in such a way that waste gas in the conduit makes indirect contact with said catalyst via the wall of said conduit;
• an ozone contactor for treating a medium with the said oxygen and ozone gas evolved in the anode compartment and separated from the water electrolyte, including means for directing the said oxygen and ozone gas separated from the water electrolyte to the ozone contactor and means for separating ozone-containing waste gas from the medium being treated, said contactor being interposed between said anode compartment and said waste gas decomposing section;
• wherein ozone-containing waste gas which is produced as a result of treatment of a medium in said ozone contactor and said hydrogen gas evolved in said cathode compartment, are converted to a harmless form.