石炭灰・焼却灰利用

[VII-65] Evaluation of long-term elution behavior of incinerated ash granulated solidification material containing heavy metals (Part 3)

*河合 達司¹、篠原 智志¹、石神 大輔¹、川端 淳一²、宮本 慎太郎³、皆川　 浩³、久田 真³ (1. 鹿島建設株式会社　技術研究所、2. 鹿島建設株式会社、3. 東北大学)

Keywords:incinerated ash , heavy metals, granulated solidification material , outdoor exposure test , carbonation

The authors conducted an outdoor exposure test to evaluate the long-term elution characteristics of heavy metals from granulated solidification matter of incineration ash. The leachate of hexavalent chromium, lead and fluorine from the incinerated ash granulated solidification material was maintained below the Japaneses groundwater environmental standard for about 4 years. The pH of the leachate decreased from alkalinity to neutral in 2 years. The concentration of sulfate ion increased up to 3 years after the start of the test. It is presumed that calcium is less likely to flow into leachate and remains in the container as calcite.