To surely prevent elution of heavy metals from a treatment object by easily and efficiently treating fly ash generated from a two-stage serial dust collector with little amount of addition of a heavy metal fixing agent, without requiring a special apparatus, or complicated control.
In this two-stage serial dust collector, exhaust gas generated from an incinerator or a melting furnace is passed through a first dust collector 2 of the dust collector serially disposed in two stages to catch fly ash. Then, after slaked lime 5 is sprayed to the exhaust gas discharged from the first dust collector 2, the exhaust gas is passed through a second dust collector 4 to catch the fly ash. Mixed ash of the first and second dust collectors is added with a phosphoric acid-based heavy metal fixing agent 13 and a chelate-based heavy metal fixing agent 14 to treat the ash.
KATO MASASHI
MATSUMOTO KATSUMI
SEKI DAIZABURO
DAIDO STEEL CO LTD