Technologies for recycling municipal waste incineration residue as cement resources – Municipal waste incineration ash washing System innovation

Introduction

Our municipal waste incineration residue recycling systems can recycle municipal waste incineration residue (Incineration bottom ash and Incineration fly ash) as cement raw materials by desalting ash. We call it waste incineration ash washing system. Features include:
① The need for landfill disposal is eliminated, disposal site lifespans can be extended.
② By incineration at a temperature of 1450°C, dioxin can be decomposed completely harmless.
③ No secondary waste is produced.
Municipal waste incineration ash washing systems have been applied to our plants, and running.
* July 2001 – Kumagaya Plant
* March 2004 – Fujiwara Plant (Incineration fly ash processing)
* April 2007 – Oita Plant (Incineration bottom ash processing)
* March 2011 – Fujiwara Plant (Incineration bottom ash processing)
* April 2013 – Kamiiso Plant (Incineration bottom ash processing)
* April 2015 – Ofunato Plant (Incineration bottom ash processing)
Since the first application, we have been trying to deal with increased volume and changes in material properties, and improving the capabilities of our systems. Through the effort, we could accumulate a lot experience and expertise.

Glossary

Incineration bottom ash

Incineration bottom ash is the combustion residue generated in waste Incineration plants. It is composed primarily of substances such as silicon dioxide (SiO2), calcium oxide (CaO), and aluminum oxide (Al2O3), main component of cement. However, it also contains materials which are not suitable as a cement raw materials, such as small amounts of scrap metal and other contaminants and 1 to 2% of chlorine.

Incineration fly ash
Incineration fly ash is fine ash carried by exhaust gas when municipal waste is incinerated, it is collected in dust collectors. Its primary components are identical to those of Incineration bottom ash, but it contains 10 to 20% of chlorine, which is not suitable as a cement raw material. It also contains trace of dioxin and other heavy metals.