Treatment of secondary fly ash by Mitsui Furnace System

摘要

50 million tons of municipal wastes are generated in Japan. 80% of them are incinerated, generating 6 million tons of bottom and fly ash. These products are stabilized and land filled. However, the area for landfill in Japan is decreasing day by day and it is very difficult to construct a new landfill area. Thus the reduction of volume of bottom and fly ash has become a very important and urgent issue. One method of accomplishing this is through a melting process. In this study the MF (Mitsui Furnace) system has been examined as a volume reduction as well as recovery of metals. The MF system is now operating to treat EAF dust and recover Zn and appears to be suitable for treatment of secondary fly ash. Secondary fly ash includes large amounts of salt and therefore the process consists of salt elimination, agglomeration and melting. In laboratory testing the salt elimination rate was more than 95%.