To provide a method of treating and disposing of the zeolite used in the waste gas treatment to remove dioxins or heavy metals in waste gases at low cost and safely regarding the treatment of heavy metals or other harmful substance in the incineration or melting treatment of waste products.

Using the zeolite produced from coal ashes containing heavy metals and a zeolite-filling adsorption tower for removing dioxins provided at behind the bag filter for treating waste gases in a waste combustion treatment system with melting function, dioxins are removed. Then, the zeolite is fed to a melting furnace in this waste disposal system to be melted and treated as slag.