D21C 11/106
Prevention of incrustations on heating surfaces during the concentration
Official title: {Prevention of incrustations on heating surfaces during the concentration, e.g. by elimination of the scale-forming substances contained in the liquors}
D21C11/106 (Prevention of incrustations on heating surfaces during the concentration) appears on 38 US grants and 17 published applications in this corpus.
Search patents in D21C- Granted patents
- 38
- Published applications
- 17
- Assignees
- 29
- Inventors
- 68
- Latest grant
- 17 Jun 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1980 | 1 | 0 |
| 1981 | 2 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 2 | 0 |
| 1985 | 3 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 1 | 0 |
| 1994 | 1 | 0 |
| 1995 | 1 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 3 | 0 |
| 1999 | 2 | 0 |
| 2000 | 2 | 0 |
| 2001 | 4 | 1 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 1 | 1 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 1 |
| 2009 | 0 | 1 |
| 2010 | 0 | 0 |
| 2011 | 3 | 1 |
| 2012 | 1 | 1 |
| 2013 | 0 | 0 |
| 2014 | 2 | 1 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 2 |
| 2018 | 0 | 1 |
| 2019 | 1 | 0 |
| 2020 | 1 | 1 |
| 2021 | 0 | 4 |
| 2022 | 1 | 0 |
| 2023 | 2 | 0 |
| 2024 | 1 | 1 |
| 2025 | 1 | 0 |
| 2026 | 0 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Black liquor viscosity reducing and anti-scale agent17 Jun 2025US 12,331,461 B2Ecolab USA Inc.
- Black liquor viscosity reducing and anti-scale agent20 Feb 2024US 11,905,655 B2Ecolab USA Inc.
- Smelt spout cleaning assembly28 Feb 2023US 11,592,175 B2The Babcock & Wilcox Company
- Furnace floor protection in recovery boilers10 Jan 2023US 11,549,682 B2Varo Teollisuuspalvelut Oy
- Apparatus and method for cleaning smelt spouts and smelt discharge openings of a chemicals recovery furnace or boiler5 Apr 2022US 11,293,636 B2Mats Bertilsson Förvaltning AB
- Compositions and methods for the removal of scale build-up in pulp and paper process30 Apr 2026US 2026/0117460 A1Solenis Technologies, L.P.
- Black liquor viscosity reducing and anti-scale agent9 May 2024US 2024/0150961 A1Ecolab USA Inc.
- Smelt spout cleaning assembly2 Dec 2021US 2021/0372614 A1The Babcock & Wilcox Company
- Black liquor viscosity reducing and anti-scale agent4 Mar 2021US 2021/0062421 A1Ecolab USA Inc.
- Furnace floor protection in recovery boilers14 Jan 2021US 2021/0010672 A1Varo Teollisuuspalvelut Oy
Most cited
By later US patents
- Method of monitoring and inhibiting scale deposition in pulp mill evaporators and concentrators37US 7,985,318 B2Nalco Company · 2011
- Process for increasing the effectiveness of slag and/or corrosion control chemicals for combustion units34US 5,894,806 AFuel Tech, Inc. · 1999
- Process for increasing the effectiveness of slag control chemicals for black liquor recovery and other combustion units22US 5,740,745 ANalco Fuel Tech · 1998
- Controlling scale in black liquor evaporators13US 5,407,583 ACalgon Corporation · 1995
- Polyacrylic acids and methyl vinyl ether/maleic anhydride copolymers as soft scale inhibitors12US 4,255,309 ABetz Laboratories, Inc. · 1981