Abstract: A method for treating drainage containing hydrogen peroxide that has been used for sterilizing and washing an inside of a water treatment system or washing and surface finishing of electronic components includes passing the drainage through the hydrogen peroxide decomposition reactor, injecting effluent water from the hydrogen peroxide decomposition reactor into a side part of the tubular container of the gas-liquid separator, and contacting the drainage with the hydrogen peroxide decomposition catalyst to decompose the hydrogen peroxide in the drainage into oxygen and water, thereby yielding the treated water.

Abstract: The present invention provides a device for treating hydrogen peroxide water, the device being capable of carrying out continuous operation and stable efficient treatment even for drainage containing relatively highly concentrated hydrogen peroxide on the order of several percent and the device having a simple configuration and a relatively compact size.