Apparatus for vitrifying blast furnace slag

An apparatus for vitrifying blast furnace slag, comprising:

• an endless conveyor belt including a pair of pulleys, said conveyor belt being formed by endlessly connecting a plurality of rectangular cooling metal members, each of said plurality of cooling metal members being of high thermal conductivity and having, on the outer surface thereof, a plurality of elongated narrow and deep cooling grooves, the longitudinal directions of said cooling grooves being substantially in parallel with the travelling direction of said endless conveyor belt, each of said plurality of cooling grooves comprising an outwardly flaring inlet section for receiving a molten blast furnace slag and an inwardly narrowing cooling section, following said inlet section, for rapidly cooling and solidifying the molten blast furnace slag into a vitreous blast furnace slag, said cooling section of each of said cooling grooves having a top end maximum width within the range of from 3 to 10 mm and a depth within the range of from 2 to 20 times said top end maximum width so as to cool the molten blast furnace slag under constraint to thereby produce a large internal strain in the vitrified blast furnace slag, the vitrified blast furnace slag being in the form of elongated sheets having a maximum thickness of 3 to 10 mm;
• driving means, connected to at least one of said pair of pulleys, for driving said endless conveyor belt;
• a molten slag container arranged above the upstream of the upper forwarding position of said endless conveyor belt, said molten slag container being adapted to receive a molten blast furnace slag discharged from a blast furnace and pour said molten blast furnace slag thus received into said plurality of cooling grooves of said cooling metal member reaching the upstream of the upper forwarding position of said endless conveyor belt along with the travel of said endless conveyor belt;
• a stripper arranged, in the upstream of the lower returning position of said endless conveyor belt, at a prescribed position adjacent to the back surface of said endless conveyor belt, said stripper being adapted to take out a cooled and solidified vitreous blast furnace slag in said plurality of cooling grooves of said cooling metal member;
• and,
• a cooling means arranged at a prescribed position in the lower returning position of said endless conveyor belt, said cooling means being adapted to sequentially cool said cooling metal members heated by the high-temperature molten blast furnace slag poured into said cooling grooves after stripping the vitreous blast furnace slag.