To solve the problem that the pressure in a furnace is raised when a large amount of air is supplied thereto from a tuyere and thus continuous discharge of residue becomes difficult, which is ascribed to the necessity of maintaining the temperature of a coke bed high by positively combusting the coke in order to combust the combustible residue before it reaches the coke bed and keep the flowability of molten slag in a shaft furnace system.
A method for gasifying and melting dust is performed by supplying dust and coke into the shaft furnace, combusting and gasifying the dust in an atmosphere having an oxygen amount equal to or less than a stoichiometric oxygen amount with respect to the combustible substances, and melting and discharging the residue from a residue exit. A coke layer is formed on the bottom of the furnace, and a high temperature gas containing 10 to 30% of oxygen of the stoichiometric oxygen amount with respect to the combustible substances, is blown from a plasma torch toward the coke layer.
YAGI SHINICHIRO
HIROSE KATSUNORI
HAGIWARA HIROYUKI
