Method for culturing cold-resistant nitrifying bacteria, method for treating nitrogen-containing water, and device for treating nitrogen-containing water
US-2026062666-A1 · Mar 5, 2026 · US
comprising treatment of the recirculated sludge
comprising treatment of the recirculated sludge · Cooperative Patent Classification (CPC)
Chemical and metallurgical processes, compounds, and materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | C02F3/1221 |
| Official title | {comprising treatment of the recirculated sludge} |
| Display label | comprising treatment of the recirculated sludge |
| Total patents | 60 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is declining.
| Year | Patents |
|---|---|
| 2015 | 6 |
| 2016 | 5 |
| 2017 | 5 |
| 2018 | 2 |
| 2019 | 6 |
| 2020 | 8 |
| 2021 | 11 |
| 2022 | 5 |
| 2023 | 2 |
| 2024 | 4 |
| 2025 | 5 |
| 2026 | 1 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Phosphorus-containing water treatment method and phosphorus-containing water treatment device
US-2025197260-A1 · Jun 19, 2025 · US
Wet air oxidation of wastewater sludge solids
US-2025122111-A1 · Apr 17, 2025 · US
System and Method for the Control of Mixed Liquor Fermentation
US-2025091920-A1 · Mar 20, 2025 · US
Use of Flotation for Separation and Thickening of Ballasted Sludge
US-2025042796-A1 · Feb 6, 2025 · US
Membrane bioreactor system for treating wastewater using oxygen
US-2025002386-A1 · Jan 2, 2025 · US
Reflux unit and sewage treatment system
US-12172914-B2 · Dec 24, 2024 · US
Reflux unit and sewage treatment system
US-2024270619-A1 · Aug 15, 2024 · US
Biomass selection and control for continuous flow granular/flocculent activated sludge processes
US-11919787-B2 · Mar 5, 2024 · US
Biomass selection and control for continuous flow granular/flocculent activated sludge processes
US-11912592-B2 · Feb 27, 2024 · US
Biomass selection and control for continuous flow granular/flocculent activated sludge processes
US-11851352-B2 · Dec 26, 2023 · US
Semiconductor process wastewater treatment system and semiconductor process wastewater treatment method using the same
US-11760674-B2 · Sep 19, 2023 · US
Recovery system of composite powder carrier in HPB municipal wastewater treatment
US-11472725-B2 · Oct 18, 2022 · US
System and Method for Treating Wastewater That Includes Biosorption and Filtration
US-2022194831-A1 · Jun 23, 2022 · US
High solids dissolved air flotation system and methods
US-11352275-B2 · Jun 7, 2022 · US
Semiconductor process wastewater treatment system and semiconductor process wastewater treatment method using the same
US-2022127177-A1 · Apr 28, 2022 · US
Apparatus and method for treatment of wet organic matter to produce biogas
US-11268057-B2 · Mar 8, 2022 · US
Process for the treatment of sludge
US-11198632-B2 · Dec 14, 2021 · US
Biomass Selection and Control for Continuous Flow Granular/Flocculent Activated Sludge Processes
US-2021380442-A1 · Dec 9, 2021 · US
Biomass Selection and Control for Continuous Flow Granular/Flocculent Activated Sludge Processes
US-2021380441-A1 · Dec 9, 2021 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC C02F3/1221?
- CPC C02F3/1221 is the Cooperative Patent Classification code for “comprising treatment of the recirculated sludge.”
- How many patents are filed under CPC C02F3/1221 (comprising treatment of the recirculated sludge)?
- Our database includes 60 publications tagged with this CPC code.
- Is patent activity under CPC C02F3/1221 growing?
- Publication counts under this code: 4 in 2024 vs 5 in 2025 (latest complete years).