ABSTRACT
Approximately 75%–77% of the total Municipal Solid Waste (MSW) generated in Japan is being incinerated annually (Sakai et al. 2000). In the year 2012, 4.7 million tons of incineration residues have been generated (Yang et al. 2014). Municipal Solid Waste Incineration (MSWI) Bottom Ash (BA) mainly consists of fine materials, melt components, ceramics, stones, glass, metallic components as well unburned organic matters (Petrovic & Thomas 2008). The presence of metallic components in bottom ash, especially aluminum restrains the reuse of BA in many recycling activities including road construction and concrete production (Pacqueuer et al. 2001; Muller & Rubner 2006). When fresh and moist BA is stored at oxygen deprived environment, the metallic aluminum react with water to generate hydrogen gas (Arm & Linderberg 2006; Mizutani et al. 2000). Typical Japanese bottom ash contains 6-13 (wt.%) aluminum. Aluminum in the MWSI bottom ash can remain dormant for years. However, when aluminum comes into contact with alkaline water (pH ≥ 9), chemical reaction will occur (Petrovic & Thomas 2008) which will eventually generate hydrogen gas.
