Abstract
Since the bottom ash or fly ash from the municipal solid waste incinerator contains heavy metals or dioxins, it is necessary to be detoxified after the incineration. One of the popular processes is the vitrification of the ash to produce slag. NKK developed the ash melting system using slag electric resistance furnace and commercialized it. The computational analysis of electro-magnetic field and thermal fluid dynamics of the slag in the slag electric resistance furnace clarified the temperature distribution and the fluid flow in the slag bath. The results are coincident with the observation of the small scale slag electric resistance furnace. The slag is heated by the Joule heat at the each electrode and the heated slag rises along the electrode due to the reduction of its density and diverse at the top of the slag bath from the electrode. The buoyancy is found to be the major driving force of the fluid flow in the bath.
