D21D 5/00
Purification of the pulp suspension by mechanical means
Official title: Purification of the pulp suspension by mechanical means; Apparatus therefor (centrifuges, cyclones B04)
D21D5/00 (Purification of the pulp suspension by mechanical means) appears on 826 US grants and 376 published applications in this corpus.
Search patents in D21D- Granted patents
- 826
- Published applications
- 376
- Assignees
- 259
- Inventors
- 936
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 7 | 0 |
| 1977 | 3 | 0 |
| 1978 | 8 | 0 |
| 1979 | 12 | 0 |
| 1980 | 19 | 0 |
| 1981 | 21 | 0 |
| 1982 | 12 | 0 |
| 1983 | 13 | 0 |
| 1984 | 20 | 0 |
| 1985 | 17 | 0 |
| 1986 | 17 | 0 |
| 1987 | 24 | 0 |
| 1988 | 14 | 0 |
| 1989 | 16 | 0 |
| 1990 | 27 | 0 |
| 1991 | 36 | 0 |
| 1992 | 33 | 0 |
| 1993 | 37 | 0 |
| 1994 | 22 | 0 |
| 1995 | 23 | 0 |
| 1996 | 23 | 0 |
| 1997 | 29 | 0 |
| 1998 | 24 | 0 |
| 1999 | 27 | 0 |
| 2000 | 35 | 0 |
| 2001 | 16 | 11 |
| 2002 | 24 | 12 |
| 2003 | 23 | 17 |
| 2004 | 12 | 27 |
| 2005 | 12 | 19 |
| 2006 | 12 | 19 |
| 2007 | 8 | 21 |
| 2008 | 7 | 11 |
| 2009 | 6 | 12 |
| 2010 | 11 | 16 |
| 2011 | 9 | 11 |
| 2012 | 16 | 11 |
| 2013 | 7 | 13 |
| 2014 | 12 | 8 |
| 2015 | 9 | 21 |
| 2016 | 11 | 13 |
| 2017 | 11 | 11 |
| 2018 | 9 | 14 |
| 2019 | 11 | 20 |
| 2020 | 11 | 17 |
| 2021 | 14 | 10 |
| 2022 | 13 | 10 |
| 2023 | 9 | 16 |
| 2024 | 13 | 17 |
| 2025 | 12 | 11 |
| 2026 | 9 | 8 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Method for fractionation of highly refined cellulose6 Oct 2026US 12,753,551 B2Stora Enso OYJ
- System and method for fiber cleaning, alignment, and sizing30 Jun 2026US 12,668,919 B1
- Accept tank mixing arrangement30 Jun 2026US 12,668,920 B2Andritz Inc.
- Method for treating textile fibers of different lengths16 Jun 2026US 12,655,583 B2Valmet Technologies Oy
- Dispersion device and accumulation device26 May 2026US 12,637,807 B2Seiko Epson Corporation
- Process for producing a fibrous material27 Aug 2026US 2026/0250912 A1Stora Enso OYJ
- Process of using non-wood fibers to create paper pulp16 Jul 2026US 2026/0201639 A1
- Methods for producing pulp and paper products from plants having bast and hurd fibers25 Jun 2026US 2026/0176819 A1Goldcup 33965 AB (Unc. Hejmas Agrifibre Technologies AB)
- Screen, in particular pressure screen2 Apr 2026US 2026/0091329 A1Andritz Fiedler GmbH
- Systems and methods for monitoring reject streams from fiber processing units5 Feb 2026US 2026/0035859 A1Kadant Black Clawson LLC
Most cited
By later US patents
- Apparatus for fluidizing, degassing and pumping a suspension of fibrous cellulose material130US 5,209,641 AKamyr, Inc. · 1993
- Process for performing reactions in a liquid-solid catalyst slurry88US 5,527,473 A1996
- Integrated paper pulp and process machinery having integrated drive and control and methods of use thereof85US 6,617,720 B1Kadant Black Clawson LLC · 2003
- Screen basket having a removable and replaceable cylindrical mesh liner71US 5,968,357 AVoith Sulzer Paper Technology North America, Inc. · 1999
- Wave screen plate63US 4,954,249 ABeloit Corporation · 1990