Nippon Kokan Kabushiki Kaisha

Ryo Ando

Gyoichi Suzuki

Kazuyoshi Sato

Shoji Kubodera

Tatsuo Koyama

Renichi Kondo

Kazuo Sano

Akira Honda

Hideyuki Yoshikoshi

Takao Miyazaki

Seishiro Nagaoka

Shigeru Araki

Yogiro Yamaoka

Hideaki Hoshi

A method and an apparatus for manufacturing a crystalline blast furnace slag, which comprises: endlessly connecting at prescribed intervals a plurality of rectangular metal cooling bodies each with a hollow for cooling water, to form a plurality of cooling grooves with a width at the top end thereof of from 40 to 80 mm corresponding to said prescribed intervals and a depth of from 100 to 300 mm and becoming narrower toward the depth thereof, each between two adjacent ones of said cooling bodies; continuously pouring a molten blast furnace slag sequentially into said plurality of cooling grooves in an atmosphere of an inert gas and/or a reducing gas, while moving said plurality of cooling bodies endlessly connected in circulation in the connecting direction thereof; and, circulating a cooling water through said hollows for cooling water of said plurality of cooling bodies during the pouring of said molten blast furnace slag into said plurality of cooling grooves, to cool said plurality of cooling bodies, thereby cooling and solidifying said molten blast furnace slag poured into said plurality of cooling grooves by the contact with mutually facing outer surfaces of two adjacent ones of said cooling bodies thus cooled, to manufacture a crystalline blast furnace slag.

Method and apparatus for manufacturing crystalline blast furnace slag

An apparatus for vitrifying blast furnace slag, which comprises:

Apparatus for vitrifying blast furnace slag

An apparatus for manufacturing a vitreous blast furnace slag, comprises a rotary drum having a circular barrel formed by endlessly connecting a plurality of rectangular cooling metal members, each of said cooling metal members having a plurality of narrow and deep cooling grooves on the outer surface thereof for rapidly cooling and solidifying a molten blast furnace slag into a vitreous blast furnace slag; a driving mechanism for rotating said rotary drum; a molten blast furnace slag feeder arranged above said rotary drum for pouring a molten blast furnace slag into said cooling grooves; a stripper stationarily arranged at a prescribed position adjacent to the inner surface of the barrel of said rotary drum, for taking out a cooled and solidified vitreous blast furnace slag in said cooling grooves; and, a cooling tank containing cooling water, arranged below said rotary drum so that the lower portion of the barrel of said rotary drum is immersed in the cooling water for cooling said cooling metal members heated by the high-temperature molten blast furnace slag poured into said cooling grooves.

Apparatus for manufacturing vitreous blast furnace slag

A process for recovering and utilizing useful substances from a molten metal produced, when manufacturing a steel slag cement from a steel slag discharged from a top-blowing oxygen converter, during a reduction treatment of steel slag, which comprises the steps of: subjecting, in an acidic refining furnace, said molten metal to a primary oxidation refining treatment and a secondary oxidation refining treatment to recover a primary slag containing a large amount of TiO.sub.2 and SiO.sub.2 and a secondary slag containing a large amount of MnO and V.sub.2 O.sub.5, said primary slag being utilized as a blast furnace burden raw material serving as a TiO.sub.2 source, and said secondary slag being utilized as a raw material for producing ferromanganese and ferrovanadium; then, subjecting, in a basic Kaldo furnace, said molten metal to an oxidation refining treatment several times to recover a low-phosphorus high-quality steel and a slag, said slag being utilized as a Thomas phosphoric fertilizer.

Process for recovering and utilizing useful substances from molten metal

A steel slag cement manufactured by reducing a steel slag discharged from a steelmaking furnace such as a converter, an open-hearth furnace or an electric arc furnace, and then oxidizing the steel slag thus reduced, which consists of, in weight percentage:

Steel slag cement and method for manufacturing same

The swirling burner comprises a vertical combustion chamber and an annular blast member located beneath the combustion chamber and provided with a central cylindrical space and a plurality of alternately superposed fuel gas passages and air passages. These passages are communicated with the cylindrical space through blow openings which are inclined in the same direction with respect to the radii of the cylindrical space. In a modification, the burner is further combined with straight blowing type burner for promoting the effect of the air-gas mixing.

Swirling burners for use in hot blast stoves

A grain coke is packed in a vertical furnace between a pair of opposite electrodes for passing current through the coke, thus heating the same to a temperature of above 1400.degree. C, preferably 1500.degree. C for more than 10 minutes. Coke is loaded into the furnace from an upper portion and heat treated coke is cooled and then discharged from the bottom. Inert or reducing gas may be introduced into the lower portion of the furnace and discharged from the upper portion thereby cooling heat treated coke and preheating loaded coke.

Method and apparatus for denitrifying coke

Molten pig iron is desulfurized, dephosphorized or otherwise refined by continuously admitting the molten pig iron into a stirring tank having an oval horizontal cross-section, causing the molten pig iron to flow in the longitudinal direction of the tank. An additive is incorporated into the stirring tank. Portions of the pig iron near the interface between the same and the additive are stirred by means of a plurality of vertical stirring rods or vanes which are suspended above the tank and project into the molten pig iron. Adjacent stirring rods or vanes are rotated in opposite directions such that their loci of rotations overlap with each other.

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Yokohama, Japan

Ryo Ando