Processing of refractory organic waste water using ozone and novel agitation method

A novel agitation method using ozone was applied to removing BOD5, CODMn, color, and NH4-N in organic waste water filled in a cylindrical vessel. The organic waste water was agitated by injecting the same organic waste water into the bath through a centered bottom nozzle. Its flow rate was adjusted to form a jet above the nozzle. A pump was used for draining the organic waster water through four nozzles settled on the bottom of the vessel and circulating it until the aforementioned four quantities were sufficiently decreased. The swirl motion of the jet appeared under certain injection conditions. The bath was strongly agitated in the presence of the swirl motion. An ozone and air mixture therefore was supplied into the nozzle and then introduced into the bath with the jet. The rate constants of BOD5, CODMn, color, and NH4-N were highly enhanced by this method compared to the conventional method using aeration of an ozone-air mixture supplied through a perforated plate.