System and method for reducing iron oxide to metallic iron using coke oven gas and oxygen steelmaking furnace gas
US8496730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 2011 |
| Grant date | Jul 30, 2013 |
| Priority date | — |
| Expiry date | Feb 15, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/143
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for the direct reduction of iron ore when the external source of reductants is one or both of coke oven gas (COG) and basic oxygen furnace gas (BOFG). Carbon dioxide (CO2) is removed from a mixture of shaft furnace off gas, obtained from a conventional direct reduction shaft furnace, and BOFG. This CO2 lean gas is mixed with clean COG, humidified, and heated in an indirect heater. Oxygen (O2) is injected into the heated reducing gas. This hot reducing gas flows to the direct reduction shaft furnace for use. The spent hot reducing gas exits the direct reduction shaft furnace as shaft furnace off gas, produces steam in a waste heat boiler, is cleaned in a cooler scrubber, and is compressed and recycled to join fresh BOFG. A portion of the shaft furnace off gas is sent to the heater burners. The BOFG and COG are also employed for a variety of other purposes in the process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.