Device for manufacturing molten iron

Patent metadata

Field	Value
Publication number	US-12084731-B2
Application number	US-201917294197-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Nov 22, 2018
Publication date	Sep 10, 2024
Grant date	Sep 10, 2024

Abstract

A device for manufacturing molten iron is provided. The device for manufacturing the molten iron includes a multi-stage fluidized reduction furnace for reducing a powdered iron ore including hematite and limonite, a melting gas furnace connected to the fluidized reduction furnace through an ore conduit and a gas conduit, a fluidized bed oxidation furnace for oxidizing magnetite to be converted into hematite through steam provided from the fluidized reduction furnace, and a hydrogen processing unit for processing hydrogen generated by the oxidation reaction of magnetite in the fluidized bed oxidation furnace.

First claim

What is claimed is:

1. A device for manufacturing a molten iron comprising:
a multi-stage fluidized reduction furnace for reducing a powdered iron ore including hematite and limonite;
a melting gas furnace connected to the fluidized reduction furnace through an ore conduit and a gas conduit;
a fluidized bed oxidation furnace for oxidizing magnetite to be converted into hematite through steam provided from the fluidized reduction furnace;
a hydrogen processing unit for processing hydrogen generated by the oxidation reaction of magnetite in the fluidized bed oxidation furnace;
a heat recovery device for recovering heat of the reduced gas discharged from the fluidized reduction furnace and generating steam;
a steam supply line connecting the fluidized bed oxidation furnace and the heat recovery device and supplying the steam generated in the heat recovery device to the fluidized bed oxidation furnace; and
a hydrogen rich gas exhaust line for discharging a hydrogen rich gas generated from the fluidized bed oxidation furnace,
wherein the hydrogen processing unit includes:
a scrubber that is connected to the hydrogen rich gas exhaust line and removes steam and magnetite dust included in the hydrogen rich gas,
a compressor connected to the scrubber and boosting the hydrogen rich gas discharged from the scrubber, and
a first gas circulation line that connects the compressor and the melting gas furnace and supplies the hydrogen rich gas to the melting gas furnace.

2. The device for manufacturing the molten iron of claim 1 , further comprising
a hematite supply conduit for connecting the fluidized bed oxidation furnace and the ore conduit and supplying hematite oxidized in the fluidized bed oxidation furnace to the fluidized reduction furnace through the ore conduit.

3. The device for manufacturing the molten iron of claim 1 , further comprising:
an auxiliary gas supply unit connected to the steam supply line and supplying an auxiliary gas as air or nitrogen gas to the fluidized bed oxidation furnace.

4. The device for manufacturing the molten iron of claim 1 , wherein
the hydrogen processing unit further includes
a second gas circulation line that connects the first gas circulation line and the gas conduit and supplies the hydrogen rich gas to the fluidized reduction furnace through the gas conduit.

5. The device for manufacturing the molten iron of claim 4 , wherein
the first gas circulation line and the second gas circulation line are connected through a three-way valve.

6. The device for manufacturing the molten iron of claim 4 , wherein
the hydrogen processing unit further includes
a hydrogen purifier connected to the first gas circulation line and separating a hydrogen gas from the hydrogen rich gas, and
a hydrogen storage tank connected to the hydrogen purifier and storing a hydrogen gas separated from the hydrogen purifier.

Assignees

• Posco
• Posco Co Ltd

Inventors

• Ko Chang Kuk
• Shin Myoung Kyun

Classifications

• F27B15/02

  Details, accessories or equipment specially adapted for furnaces of these types · CPC title

• C21B2300/02

  Particular sequence of the process steps · CPC title

• C21B13/14

  Multi-stage processes {processes carried out in different vessels or furnaces} · CPC title

• C21B13/0073

  Selection or treatment of the reducing gases · CPC title

• C21B13/0033 Primary

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