The objective of this project is to build up the leaching baseline for environmental application of recycled aggregates. According to the Environmental Protection Agency’s announcement on May 18, 2020, “Municipal Solid Waste Incineration Bottom Ash Recycling Management Regulations”, this project had studied and analyzed the incineration recycled aggregates and other inorganic recycled aggregates using “Recycled Aggregates Environmental Leaching Procedure (NIEA R222)”. In order to evaluate the variation on metal leaching between same batch incineration bottom ash and recycled aggregates from recycling facility, experiments had conducted including natural aging process test and Controlled-Low-Strength-Materials (CLSM) long-term immersion test, for verification the suitability of incineration recycled aggregates environmental standards. According to the 45 days natural aging process results, it indicated that a significant reduced of lead (Pb) and copper (Cu) leaching concentration from either surface or middle level of incineration bottom ash samples meet requirements of “the second category of incineration recycled aggregates environmental standards”, which effective date is on January 1, 2021. On the other hand, the results of all CLSM samples after 6 months immersion within groundwater showed that all samples’ metal leaching concentration close to the background concentration and meet the requirement of “the first category of groundwater pollution control standards.” On the basis of the experiment results, this project evaluated the principle and mechanism of sorting, aging, washing, and stabilization treatment technologies, as well as summarized appropriate treatment approaches for incineration recycled aggregates to implement the incineration recycled aggregates environmental standards. A draft of “A guideline of Incineration Recycled Aggregates Treatment Technologies” has completed to provide government authorities and related concerned executive making the management strategies. Meanwhile, the project applied the “Recycled Aggregates Environmental Leaching Procedure (NIEA R222)” to examine different types of inorganic recycled aggregates, such as basic-oxygen-furnace (BOF) slag, reducing slag, coal fly/bottom ash, etc. The examined results refer to the first and second categories of “Groundwater Pollution Control Standards” has been suggested the management strategies for inorganic recycled aggregates environmental standards.

Incinerator Bottom Ash, Recycled Aggregates, Recycled Aggregates Environmental Leaching Procedure