Effects of sprinkling, carbonation and mixing of iron materials and auxiliary materials on the mechanical and elution characteristics of municipal solid waste incineration bottom ash as a civil engineering material

Abstract

In order to reduce the amount of waste to be disposed of in landfill, the recycling of municipal solid waste (MSW) incineration bottom ash is of urgent need in Japan. This study aims to recycle MSW bottom ash as civil engineering materials. MSW bottom ash from 6 locations nationwide was used to investigate the effect on the elution characteristics by sprinkling water and conducting carbonation via the column test, as well as the impact on the mechanical characteristics using bottom ash from one of the locations. While Pb was confirmed to be immobilized due to carbonation, the tendency for the elution of Cr(VI) was shown to have increased. It was also suggested from decrease in the modified CBR value that carbonation affects the mechanical properties of bottom ash. Additionally, the effects of mixing iron materials and auxiliary materials with MSW bottom ash to immobilize heavy metals as well as to improve mechanical properties.