Method for producing sintered ore

Patent metadata

Field	Value
Publication number	US-2023085232-A1
Application number	US-202117801141-A
Country	US
Kind code	A1
Filing date	Feb 22, 2021
Priority date	Feb 27, 2020
Publication date	Mar 16, 2023
Grant date	—

Abstract

A method produces a high-strength sintered ore while maintaining a high production rate by performing appropriate oxygen enrichment at a position closer to an ore discharging section than an ignition position without using gaseous fuel in the operation of a sintering machine. In a method for producing sintered ore including sequentially combusting carbonaceous material in a sinter bed (raw material charged layer) in a DL sintering machine to sinter the mixed raw material, in performing oxygen enrichment from above the raw material charging layer on the sintering machine, the oxygen enrichment is performed at a position closer to the ore discharging section than the position where 4 minutes have passed since the upper surface of the charging layer was ignited

First claim

1 . A method for producing sintered ore comprising
charging mixed raw material for sintering containing iron ore and carbonaceous material into a raw material ore charging section on a pallet that circulates in a sintering machine to thus form a raw material charged layer, igniting the carbonaceous material on an upper surface (upper layer part) of the raw material charged layer by an ignition furnace disposed downstream of the raw material ore charging section while sucking gas above the raw material charged layer through a wind box disposed below the pallet, introducing the gas into the raw material charged layer to sequentially ignite the carbonaceous material in the raw material charged layer and thus sinter the mixed material, wherein in performing oxygen enrichment from above the raw material charging layer on the sintering machine, the oxygen enrichment is performed at a position closer to an ore discharging section than the position where 4 minutes have passed since the upper surface of the charging layer was ignited.

2 . The method for producing sintered ore according to claim 1 , wherein
the oxygen enrichment is completed within 13 minutes after the raw material charging layer is ignited.

3 . The method for producing sintered ore according to claim 1 , wherein
the time of the oxygen enrichment to the raw material charged layer is from 1 to 7 minutes as a passage time of the mixed raw material for sintering.

4 . The method for producing sintered ore according to claim 1 , wherein
the oxygen enrichment is not performed until 4 minutes have elapsed after the upper surface of the charging layer is ignited.

5 . The method for producing sintered ore according to claim 1 , wherein
the method is not used in combination with an exhaust gas recirculation process.

6 . The method for producing sintered ore according to claim 1 , wherein
the oxygen concentration of the oxygen-enriched air to be introduced onto the raw material charged layer is more than 25 vol. %.

7 . The method for producing sintered ore according to claim 2 , wherein
the time of the oxygen enrichment to the raw material charged layer is from 1 to 7 minutes as a passage time of the mixed raw material for sintering.

8 . The method for producing sintered ore according to claim 2 , wherein
the oxygen enrichment is not performed until 4 minutes have elapsed after the upper surface of the charging layer is ignited.

9 . The method for producing sintered ore according to claim 3 , wherein
the oxygen enrichment is not performed until 4 minutes have elapsed after the upper surface of the charging layer is ignited.

10 . The method for producing sintered ore according to claim 7 , wherein
the oxygen enrichment is not performed until 4 minutes have elapsed after the upper surface of the charging layer is ignited.

11 . The method for producing sintered ore according to claim 2 , wherein
the method is not used in combination with an exhaust gas recirculation process.

12 . The method for producing sintered ore according to claim 3 , wherein
the method is not used in combination with an exhaust gas recirculation process.

13 . The method for producing sintered ore according to claim 7 , wherein
the method is not used in combination with an exhaust gas recirculation process.

14 . The method for producing sintered ore according to claim 2 , wherein
the oxygen concentration of the oxygen-enriched air to be introduced onto the raw material charged layer is more than 25 vol. %.

15 . The method for producing sintered ore according to claim 3 , wherein
the oxygen concentration of the oxygen-enriched air to be introduced onto the raw material charged layer is more than 25 vol. %.

16 . The method for producing sintered ore according to claim 7 , wherein
the oxygen concentration of the oxygen-enriched air to be introduced onto the raw material charged layer is more than 25 vol. %.

Assignees

• Jfe Steel Corp

Inventors

• Takehara Kenta
• Yamamoto Tetsuya
• Higuchi Takahide

Classifications

• C21B13/0086

  Conditioning, transformation of reduced iron ores · CPC title

• C22B1/20

  in sintering machines with movable grates · CPC title

• C22B1/18 Primary

  in sinter pots · CPC title

• F27B21/00

  Open or uncovered sintering apparatus; Other heat-treatment apparatus of like construction · CPC title

• C21B13/004

  in a continuous way by reduction from ores · CPC title