Method for manufacturing reduced iron

Patent metadata

Field	Value
Publication number	US-10557179-B2
Application number	US-201715700212-A
Country	US
Kind code	B2
Filing date	Sep 11, 2017
Priority date	Sep 17, 2009
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

Provided is a method for manufacturing reduced iron which includes the steps of: i) drying ores in an ore drier; ii) supplying the dried ores to at least one reduction reactor; iii) reducing the ores in the at least one reduction reactor and manufacturing reduced iron; iv) discharging exhaust gas by which the ores are reduced in the reduction reactor; v) branching the exhaust gas and providing the branched exhaust gas as ore feeding gas; and vi) exchanging heat between the exhaust gas and the ore feeding gas and transferring the sensible heat of the exhaust gas to the ore feeding gas. In the supplying the dried ores to the at least one reduction reactor, the dried ores are supplied to the at least one reduction reactor by using the ore feeding gas.

First claim

What is claimed is:

1. A method for manufacturing reduced iron, comprising:
drying ores in an ore drier;
supplying the dried ores to at least one reduction reactor;
reducing the ores in the at least one reduction reactor and manufacturing reduced iron;
discharging exhaust gas by which the ores are reduced in the at least one reduction reactor;
branching the exhaust gas and providing the branched exhaust gas as ore feeding gas; and
exchanging heat between the exhaust gas and the ore feeding gas and transferring the sensible heat of the exhaust gas to the ore feeding gas,
wherein in the supplying of the dried ores to the at least one reduction reactor, the dried ores are supplied to the at least one reduction reactor by using the ore feeding gas, and
wherein the supplying of the dried ores to the at least one reduction reactor comprises supplying the dried ores along a first direction, supplying the dried ores along a second direction crossing the first direction and raising the dried ores along the second direction, and supplying the dried ores to the at least one reduction reactor through a plurality of third feeding gas pipe parts connected to the at least one reduction reactor in a radial direction.

2. The method for manufacturing reduced iron of claim 1 , wherein in the supplying of the dried ores to the at least one reduction reactor, a direction in which the dried ores are supplied to the at least one reduction reactor coincides with a direction in which the ore feeding gas flows and the dried ores are supplied to the at least one reduction reactor in a linear flow.

3. The method for manufacturing reduced iron of claim 1 , wherein in the supplying of the dried ores along the first direction, an amount of moisture in the dried ores supplied along the first direction is more than 0 and not more than 7 wt %.

4. The method for manufacturing reduced iron of claim 1 , wherein the supplying of the dried ores to the at least one reduction reactor further comprises flowing the dried ores in an air-tight space between the second direction and a third direction.

5. The method for manufacturing reduced iron of claim 1 , wherein in the branching of the exhaust gas and providing the branched exhaust gas as the ore feeding gas, the exhaust gas is compressed before being branched.

6. The method for manufacturing reduced iron of claim 1 , wherein in the branching of the exhaust gas and providing the branched exhaust gas as the ore feeding gas, after dust contained in the exhaust gas is collected in a dry fashion, the exhaust gas is branched.

7. The method for manufacturing reduced iron of claim 1 , wherein in the transferring of the sensible heat of the exhaust gas to the ore feeding gas, a flow direction of the exhaust gas is opposite to a flow direction of the ore feeding gas in a heat exchanger.

8. The method for manufacturing reduced iron of claim 1 , wherein in the supplying of the dried ores to the at least one reduction reactor, a temperature of the ore feeding gas is 150° C. to 300° C.

Assignees

• Posco
• Primetals Technologies Austria GmbH

Inventors

• Shin Myoung-Kyun
• Kim Dong-Won
• Kim Sang-Hyun
• Lee Jun-Hyuk
• Friedemann Plaul Jan
• Rein Norbert
• Zehetbauer Karl

Classifications

• C21B2100/40

  Gas purification of exhaust gases to be recirculated or used in other metallurgical processes · CPC title

• C21B13/0033 Primary

  In fluidised bed furnaces or apparatus containing a dispersion of the material · CPC title

• C21B2100/66

  Heat exchange · CPC title

• C21B13/143

  Injection of partially reduced ore into a molten bath · CPC title

• C21B2100/80

  Interaction of exhaust gases produced during the manufacture of iron or steel with other processes · CPC title