D21C 11/0021
Introduction of various effluents
Official title: {Introduction of various effluents, e.g. waste waters, into the pulping, recovery and regeneration cycle (closed-cycle)}
D21C11/0021 (Introduction of various effluents) appears on 113 US grants and 40 published applications in this corpus.
Search patents in D21C- Granted patents
- 113
- Published applications
- 40
- Assignees
- 59
- Inventors
- 181
- Latest grant
- 17 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 2 | 0 |
| 1978 | 0 | 0 |
| 1979 | 1 | 0 |
| 1980 | 2 | 0 |
| 1981 | 2 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 2 | 0 |
| 1989 | 1 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 3 | 0 |
| 1993 | 3 | 0 |
| 1994 | 6 | 0 |
| 1995 | 6 | 0 |
| 1996 | 11 | 0 |
| 1997 | 8 | 0 |
| 1998 | 8 | 0 |
| 1999 | 3 | 0 |
| 2000 | 8 | 0 |
| 2001 | 4 | 1 |
| 2002 | 6 | 2 |
| 2003 | 3 | 3 |
| 2004 | 3 | 2 |
| 2005 | 1 | 0 |
| 2006 | 0 | 3 |
| 2007 | 2 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 5 |
| 2011 | 0 | 1 |
| 2012 | 1 | 1 |
| 2013 | 1 | 0 |
| 2014 | 4 | 2 |
| 2015 | 3 | 8 |
| 2016 | 6 | 4 |
| 2017 | 4 | 2 |
| 2018 | 0 | 1 |
| 2019 | 1 | 1 |
| 2020 | 1 | 1 |
| 2021 | 1 | 1 |
| 2022 | 0 | 0 |
| 2023 | 0 | 0 |
| 2024 | 0 | 1 |
| 2025 | 0 | 0 |
| 2026 | 1 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Method for processing bark press water from sawmills and/or pulp mills17 Feb 2026US 12,553,181 B2SöDra SkogsäGarna Ekonomisk FöRening
- Method of preparing a sizing boost additive22 Jun 2021US 11,041,273 B2Sca Forest Products AB
- Methods of processing plant fiber, and related systems and compositions12 May 2020US 10,648,131 B2POET Research, Inc.
- Method for utilizing lignin separated from black liquor as lime-kiln fuel15 Jan 2019US 10,179,972 B2Andritz Inc.
- Biomass treatment for hyperthermal hydrocatalytic conversion18 Jul 2017US 9,708,763 B2Shell Oil Company
- System and Process for Reducing Chemical Losses in Treating Ash Produced in a Recovery Boiler of a Wood Pulping Process12 Feb 2026US 2026/0042676 A1Veolia Water Technologies, Inc.
- Method for processing bark press water from sawmills and/or pulp mills19 Sep 2024US 2024/0307825 A1SöDra SkogsäGarna Ekonomisk FöRening
- Method of producing dissolving pulp11 Feb 2021US 2021/0040688 A1Andritz Inc.
- Catalytic conversion of lignin7 May 2020US 2020/0141057 A1SunCarbon AB
- Method of preparing a sizing boost additive19 Dec 2019US 2019/0382959 A1Sca Forest Products AB
Most cited
By later US patents
- Process for treating waste water effluent32US 5,470,480 AEka Nobel AB · 1995
- Process for the continuous digestion of cellulosic fiber material30US 5,080,755 AKamyr, Inc. · 1992
- Kraft pulp bleaching and recovery process24US 4,196,043 AScott Paper Company · 1980
- Process for recycling bleach plant filtrate22US 5,352,332 A1994
- Bleach plant filtrate recovery21US 4,039,372 AErco Envirotech Ltd. · 1977