C02F 3/22
Using circulation pipes
Official title: using circulation pipes
C02F3/22 (Using circulation pipes) appears on 310 US grants and 173 published applications in this corpus.
Search patents in C02F- Granted patents
- 310
- Published applications
- 173
- Assignees
- 177
- Inventors
- 510
- Latest grant
- 28 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 4 | 0 |
| 1977 | 6 | 0 |
| 1978 | 2 | 0 |
| 1979 | 3 | 0 |
| 1980 | 15 | 0 |
| 1981 | 17 | 0 |
| 1982 | 8 | 0 |
| 1983 | 10 | 0 |
| 1984 | 6 | 0 |
| 1985 | 7 | 0 |
| 1986 | 7 | 0 |
| 1987 | 3 | 0 |
| 1988 | 2 | 0 |
| 1989 | 6 | 0 |
| 1990 | 4 | 0 |
| 1991 | 7 | 0 |
| 1992 | 4 | 0 |
| 1993 | 13 | 0 |
| 1994 | 4 | 0 |
| 1995 | 1 | 0 |
| 1996 | 10 | 0 |
| 1997 | 12 | 0 |
| 1998 | 8 | 0 |
| 1999 | 4 | 0 |
| 2000 | 6 | 0 |
| 2001 | 7 | 1 |
| 2002 | 5 | 9 |
| 2003 | 5 | 4 |
| 2004 | 3 | 3 |
| 2005 | 2 | 9 |
| 2006 | 7 | 6 |
| 2007 | 6 | 10 |
| 2008 | 5 | 5 |
| 2009 | 7 | 8 |
| 2010 | 7 | 5 |
| 2011 | 2 | 6 |
| 2012 | 6 | 6 |
| 2013 | 1 | 7 |
| 2014 | 5 | 9 |
| 2015 | 7 | 11 |
| 2016 | 3 | 9 |
| 2017 | 10 | 8 |
| 2018 | 6 | 5 |
| 2019 | 9 | 8 |
| 2020 | 6 | 9 |
| 2021 | 7 | 9 |
| 2022 | 7 | 9 |
| 2023 | 8 | 7 |
| 2024 | 3 | 3 |
| 2025 | 5 | 4 |
| 2026 | 2 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Vacuum air lift systems including a fluidic oscillator28 Jul 2026US 12,692,177 B2Searen, LLC
- Tank configuration with enhanced denitrification27 Jan 2026US 12,534,392 B2KleanTu LLC
- Combined mixed-cell and raceway aquaculture device, system and method of use thereof, and method for growing fish thereby25 Nov 2025US 12,478,047 B2Jlh Consulting Inc.
- Bubble generator14 Oct 2025US 12,441,641 B2Pulse Burst Systems, LLC
- High-efficiency airlift pump12 Aug 2025US 12,384,706 B2GIS Gas Infusion Systems Inc.
- Fermentation method for recovering carboxylic acids while reducing greenhouse gas emissions30 Jul 2026US 2026/0217580 A1Shanghai Municipal Engineering Design Institute (Group) Co., Ltd.
- Aerobic Bacterial Generator23 Jul 2026US 2026/0209093 A1Sludgehammer Group, Ltd.
- Tank configuration with enhanced denitrification7 May 2026US 2026/0125302 A1KleanTu LLC
- Waste water treatment system using aerobic granular sludge gravity-driven membrane system20 Nov 2025US 2025/0353765 A1King Abdullah University of Science and Technology
- Wastewater Biological Selector System and Methods for Treating Wastewater Process Fluid19 Jun 2025US 2025/0197262 A1Red Valve Company, Inc.
Most cited
By later US patents
- Submersible aeration train and aeration apparatus for biological purification of sewage82US 5,316,671 A1994
- Equipment for gassing a liquid and process for operating the equipment80US 4,507,253 ABBC Brown, Boveri & Company, Limited · 1985
- Airlift pump apparatus and method78US 6,162,020 ANCA2BioProcess, Inc. · 2000
- Water aeration apparatus72US 4,702,830 AKaiyo Kogyo Kabushiki Kaisha · 1987
- Method of supplying air masses and producing jets of water68US 4,752,421 AKaiyo Kogyo Kabushiki Kaisha · 1988