C21B 13/146
Multi-step reduction without melting
Official title: {Multi-step reduction without melting}
C21B13/146 (Multi-step reduction without melting) appears on 28 US grants and 26 published applications in this corpus.
Search patents in C21B- Granted patents
- 28
- Published applications
- 26
- Assignees
- 31
- Inventors
- 86
- Latest grant
- 28 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 1 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 4 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 1 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 2 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 1 |
| 2008 | 1 | 2 |
| 2009 | 2 | 2 |
| 2010 | 1 | 1 |
| 2011 | 1 | 0 |
| 2012 | 1 | 2 |
| 2013 | 1 | 0 |
| 2014 | 0 | 1 |
| 2015 | 1 | 1 |
| 2016 | 0 | 4 |
| 2017 | 0 | 1 |
| 2018 | 2 | 1 |
| 2019 | 4 | 0 |
| 2020 | 1 | 0 |
| 2021 | 0 | 0 |
| 2022 | 0 | 1 |
| 2023 | 0 | 2 |
| 2024 | 1 | 2 |
| 2025 | 0 | 2 |
| 2026 | 1 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Process for the production of carburized sponge iron28 Jul 2026US 12,692,563 B2HYBRIT Development AB
- Device for manufacturing molten iron10 Sep 2024US 12,084,731 B2Posco
- Multi-stage suspension magnetizing roasting-magnetic separation system device and method for refractory iron ore28 Jan 2020US 10,543,491 B2Northeastern University
- Molten iron manufacturing apparatus and molten iron manufacturing method24 Sep 2019US 10,422,582 B2Posco
- Methods and systems for increasing the carbon content of sponge iron in a reduction furnace11 Jun 2019US 10,316,376 B2Midrex Technologies, Inc.
- Direct reduction system and method utilizing pre-reducing furnace and heat exchanger10 Sep 2026US 2026/0265849 A1Midrex Technologies, Inc.
- Extraction of elements and/or compounds from iron-containing materials such as iron-containing tailings, recovery of magnetically susceptible materials, and related systems and products2 Oct 2025US 2025/0305075 A1Phoenix Tailings, Inc.
- Method for the direct reduction of iron ore14 Aug 2025US 2025/0257416 A1ThyssenKrupp Steel Europe AG
- Induction heating of dri28 Nov 2024US 2024/0392399 A1Arcelormittal Texas Hbi LLC
- Iron briquettes19 Sep 2024US 2024/0309478 A1HYBRIT Development AB
Most cited
By later US patents
- Plant and process for fluidized bed reduction of ore48US 5,082,251 AFior de Venezuela · 1992
- Plant and process for fluidized bed reduction of ore26US 5,192,486 AFior de Venezuela · 1993
- Integrated process for thermal cracking of heavy oil and reduction of iron ores19US 4,334,920 AKoa Oil Company, Limited · 1982
- Method of preparing iron powder10US 4,054,443 AMidrex Corporation · 1977
- Direct reduction process for producing reduced iron8US 4,268,303 AKobe Steel, Ltd. · 1981