METHOD FOR DETERMINING OPTIMUM RATIO OF ADDITION OF HEAVY METAL ELUTION INHIBITOR TO BURNED FLY ASH AND METHOD FOR TREATING BURNED FLY ASH

摘要

PROBLEM TO BE SOLVED: To provide a method for simply and speedily measuring the concentration of lead in burned fly ash discharged from an incinerator and a method for determining the optimum ratio of addition of an elution inhibitor used in treatments for preventing the elution of heavy metals from the burned fly ash based on the results of the measurement. SOLUTION: In the method for measuring the concentration of lead in the burned fly ash, the concentration of lead in the burned fly ash is computed by mixing the burned fly ash from the incinerator with an alkali aqueous solution, heating the mixture to elute lead in the burned fly ash, and measuring the concentration of lead in the obtained aqueous solution. In this method for treating the burned fly ash from the incinerator, the correlation between the concentration of lead in the burned fly ash and the necessary amount of the heavy metals elution inhibitor necessary for preventing the elution of the heavy metals contained in the burned fly ash is previously obtained on the incinerator to be treated, the necessary amount of the heavy metals elution inhibitor necessary for preventing the elution of the heavy metals contained in the burned fly ash is determined based on the correlation by the concentration of lead in the burned fly ash obtained by the measuring method, and the determined necessary amount of the heavy metals elution inhibitor is added to the burned fly ash and kneaded.