CPC Definition - Subclass C02F
This place covers:
The physical, chemical and biological treatment of water, waste water or sewage, e.g. by distillation or evaporation, by degassing, by centrifugal separation, by flocculation of suspended impurities or by using plants such as algae.
Selection or use of compositions for such treatments.
Compositions (per se) specially adapted for water treatment.
Softening water and preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents.
Aeration of stretches of water.
Multistage treatment of water, waste water or sewage.
Treatment of sludge and devices therefore, e.g. bioreactors. Sludge treatment covered in this subclass is usually restricted to the treatment of sludge obtained from a water treatment process.
Devices for the treatment of water, waste water or sewage, e.g. devices for separating or removing fatty or oily substances or similar floating material.
Separation in general is classified in B01D.
This place does not cover:
Processes for making harmful chemical substances harmless, or less harmful, by effecting a chemical change in the substances | |
Settling tanks and filter devices in general | |
Adding materials to water to prevent corrosion | |
Cleaning or keeping clear the surface of open water, e.g. the sea | |
Devices for cleaning or keeping clear the surface of open water | |
Methods for obtaining or collecting drinking water or tap water | |
Treating radioactively-contaminated liquids |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Attention is drawn to the following places, which may be of interest for search:
Medicinal water | |
Degasification of liquids in general | |
Ion-exchange in general | |
Packing elements in general | |
Devices in sewers for separating liquid or solid substances from sewage | |
Methods of steam generation | |
Preheating boiler feed-water or accumulating preheated boiler feed-water | |
Incinerators or other apparatus for burning waste liquors |
When classifying in this subclass, classification is also made in group B01D 15/08 insofar as subject matter of general interest relating to chromatography is concerned.
It is desirable to add the indexing symbols of group C02F 2101/00 for the nature of the contaminant and of group C02F 2103/00 for the nature of the water, waste water, sewage or sludge to be treated which are considered to be of interest for search.
Devices are only classified in detail if there is no appropriate, more general place available and if they are clearly related to the water treatment aspect (i.e. if they are not universally applicable). The following symbols can be considered for classifying additional information:
Specifying the nature of the contaminant | |
Specifying the nature of water, waste water or sludge to be treated | |
Details of the apparatus used for treatment of water, wastewater or sludge | |
Specifying details of the apparatus and plants for the biological treatment of water, wastewater or sewage | |
Controlling or monitoring parameters in water treatment | |
Specifying general aspects of water treatment | |
Specific treatment goals | |
The use of specific compounds in water treatment | |
The location of water treatment or water treatment device |
In this place, the following terms or expressions are used with the meaning indicated:
Sludge | Solids that remain after wastewater treatment. This material may be separated, treated and composted into fertiliser. Aqueous suspension of solids resulting from water treatment processes and having a solids concentration of typically more than 2 g/L. |
This place covers:
This group covers processes and apparatus relating to physical and chemical water treatment (ultrapure water, potable water, wastewater).
Treatment concerns only water, waste water or sewage and not any liquids
This place covers:
Methods for separation of water and particles suspended in water.
This place does not cover:
Membrane treatment | |
Filter devices |
Attention is drawn to the following places, which may be of interest for search:
Membrane filters |
The head group should only be used if none of the more specific groups is appropriate.
This place covers:
This class relates to small portable filters, which are mostly pocket-sized, e.g. filters integrated in drinking straws, canteens or bottles. Bottle-filters can be further characterised using the symbol C02F 2307/02.
This place does not cover:
Household type filters |
Attention is drawn to the following places, which may be of interest for search:
Indexing symbol for bottle-filters |
This place covers:
This class contains household filters, e.g. pitchers, larger bottles, cartridges, faucet mounted devices, filters useable either in commercial or residential establishments. Additional details can be classified using Indexing symbols C02F 2307/02 - C02F 2307/06 (see the informative references).
This place does not cover:
Small-scale multistage treatment apparatus |
Attention is drawn to the following places, which may be of interest for search:
Filter as part of a bottle | |
Filter being part of a pitcher or jug | |
Filter being mounted on a faucet or showerhead | |
Apparatus for making beverages including water filters | |
Filter condition indicators | |
Liquid dispensers |
This place covers:
To be used for large scale (industrial scale) mechanical filtration, e.g. use of a sand filter, rapid filtration. Typical applications are filters in drinking water purification plants, post filtration in wastewater treatment plants, water filtration for industrial water stream.
This place covers:
Systems or processes based on supernatural or anthroposophic principles. This class is used for all esoteric applications which claim implausible effects (lack of scientific explanation, quackery).
Attention is drawn to the following places, which may be of interest for search:
Homeaopathy, esoteric applications | |
Screening of terrestrial radiation | |
Radio-esthesis, dowsing |
This place covers:
This class is used for any devices directing the water to be treated into the treatment tank or installation, e.g. pipes, connecting vessels.
This place does not cover:
Water distributors for settling tanks |
This place covers:
Control of parameters in the physical or chemical water treatment processes
This place does not cover:
Control of flocculation processes | |
Control of biological water treatment processes |
Attention is drawn to the following places, which may be of interest for search:
Control parameters and systems | |
Control in general |
This place covers:
Treatment of water by heating
Attention is drawn to the following places, which may be of interest for search:
Heat sterilisation for pharmaceuticals | |
General heat sterilisation |
This place covers:
Treatment of water using distillation, apparatus details should always be classified in the corresponding classes in B01D.
Attention is drawn to the following places, which may be of interest for search:
Seawater desalination can be indexed with the symbol C02F 2103/08.
This place covers:
Treatment of water, waste water or sewage by vapour compression
Attention is drawn to the following places, which may be of interest for search:
Evaporating with vapour compression |
This place covers:
Prevention of deposits in the context of distillation or evaporation.
Attention is drawn to the following places, which may be of interest for search:
Electrochemical prevention or elimination of deposits | |
Softening water, scale prevention | |
Elimination of deposits, scale removal or prevention being a secondary aspect |
This place covers:
Distillation / evaporation process for obtaining ultrapure water.
Symbol C02F 2103/04 should be used for all other processes producing ultrapure water.
This place covers:
Treatment of water, waste water or sewage by distillation or evaporation under vacuum produced by a barometric column
Attention is drawn to the following places, which may be of interest for search:
Vacuum distillation using a barometric column |
This place covers:
Treatment of wastewater by evaporation and distillation.
The specific type of wastewater can be further characterised using the symbols under C02F 2103/00 - C02F 2103/42.
This place covers:
Treatment of water, waste water or sewage by flash evaporation, i.e. evaporation under (non-barametric) vacuum or by sudden expansion
Attention is drawn to the following places, which may be of interest for search:
Flash distillation |
This place covers:
Treatment of water, waste water or sewage by evaporating a thin film of liquid on heated surfaces, packing elements or by using a falling film evaporator
Apparatus for filtration like thin film evaporator concerning liquid purification is classified in B01D
When the liquid purification concerns water, then it's also classified in C02F 1/08
Attention is drawn to the following places, which may be of interest for search:
Film evaporation | |
Thin layer evaporation |
This place covers:
Treatment of water, waste water or sewage by putting the water in direct contact with the heat carrier medium
Attention is drawn to the following places, which may be of interest for search:
Evaporating with heated gases in contact with the liquid |
This place covers:
Treatment of water, waste water or sewage by dispersing the water in form of droplets (spray) in a gas for evaporating
Attention is drawn to the following places, which may be of interest for search:
Evaporating by spraying |
This place covers:
Treatment of water, waste water or sewage by using solar heat directly or indirectly for evaporating water
Attention is drawn to the following places, which may be of interest for search:
Evaporating in general using solar energy |
This place covers:
Treatment of water, waste water or sewage by using waste heat from other processes, e.g. from engine cooling circuits, power plants or industrial production processes
Attention is drawn to the following places, which may be of interest for search:
Evaporating using waste energy |
This place covers:
Transportable device and process using such device for treating water by distillation.
Attention is drawn to the following places, which may be of interest for search:
Mobile apparatus and plants in general | |
Mobile biological apparatus and plants in general |
This place covers:
Processes removing dissolved gases such as oxygen, carbon dioxide or halogens. This class is also used for processes directed at removing volatile organic or inorganic compounds, e.g. ammonia. This includes stripping and vacuum processes.
Attention is drawn to the following places, which may be of interest for search:
Apparatus for degasification of liquids in general | |
Arrangement of degassing apparatus in boiler feed supply |
Indexing symbols for the compounds to be removed should be used if available (C02F 2101/00 - C02F 2101/40).
This place covers:
Processes for cleaning water by freezing, separation of ice and slush from water and subsequent melting of ice and slush, e.g. freeze desalination.
Freeze-desalination using methane-hydrates (clathrates) is classified as a combination of C02F 1/22 and C02F 1/265.
This place covers:
Water treatment processes by flotation, e.g. for separating solids and liquids dispersed in water by using microbubbles, dissolved air flotation (DAF).
This place does not cover:
Electroflotation |
Attention is drawn to the following places, which may be of interest for search:
Flotation devices |
This place covers:
Treatment of water, waste water or sewage by extraction, e.g. removing pollutant from water by extraction, solvent extraction.
Attention is drawn to the following places, which may be of interest for search:
Solvent extraction |
This place covers:
Treatment of water by sorption, removal of a compound by adsorption on a generally solid sorbent, regardless of the mechanism involved (chemisorption, complexation).
This place does not cover:
Treatment of water, waste water or sewage by ion exchange |
Attention is drawn to the following places, which may be of interest for search:
Sorbents in general |
If more than one sorbent is used the head group should be used in combination with the more specific symbols chosen from C02F 2001/422 - C02F 2001/427.
This place covers:
Water treatment using natural and synthetic inorganic sorbents. Examples for inorganic sorbents include zeolites, clays, silicagel, metal-hydroxides. Ion exchange occurring at the surface of inorganic sorbents is also classified here.
Attention is drawn to the following places, which may be of interest for search:
Inorganic sorbents |
This place covers:
Activated carbon and other coal or carbon based adsorbents, Powdered activated carbon (PAC), carbon black
Attention is drawn to the following places, which may be of interest for search:
Carbon based sorbents |
Only to be used if the carbonaceous compound is the active adsorbent (not for carriers).
This place covers:
Treatment of water, waste water or sewage by sorption using synthetic organic sorbents, e.g. organic adsorbents not occurring naturally, e.g. synthetic polymers.
Attention is drawn to the following places, which may be of interest for search:
Sorbents comprising synthetic macromolecular compounds |
This place covers:
Sorption using natural organic sorbents such as algae, compost, humic acids, cellulose, etc.
Attention is drawn to the following places, which may be of interest for search:
Sorbents comprising naturally occurring natural macromolecular compounds |
This place covers:
Processes using coated, impregnated, hybrid and multi-layered sorbents.
Attention is drawn to the following places, which may be of interest for search:
Coated solid sorbents |
Use of layered adsorbents should be classified as combination of class and additional symbol, e.g. C02F 1/288 and C02F 1/283.
This place covers:
Processes for treating water, waste water or sewage by using radiation sources, e.g. plasma, ionised gas. Irradiation with sunlight should be classified here only if the effect is not due to the UV radiation and if the effect is not achieved by heating.
This place covers:
Treatment of water with microwave radiation.
Attention is drawn to the following places, which may be of interest for search:
Disinfecting and sterilising with microwaves |
If microwaves are primarily used for heating C02F 1/02 is used.
This place covers:
Processes using ultraviolet light (light having a wavelength of approximately 100-400 nm).
Attention is drawn to the following places, which may be of interest for search:
Disinfection and sterilisation using ultraviolet light |
C02F 1/325 should always be used when apparatus details are mentioned. Photocatalysis is classified by combining C02F 1/32 or C02F 1/325 with C02F 1/74 and C02F 2305/10.
This place covers:
Devices for UV treatment.
Details should be classified by using the symbols under C02F 2201/32.
This place covers:
Processes using cavitation for the destruction of particles and substances in the water to be treated. Mechanical creation by nozzles, valves, throttles or pumps.
Attention is drawn to the following places, which may be of interest for search:
General mixing |
Can be given as additional information for sludge treatment.
This place covers:
Processes using ultrasonic transducer or similar devices to create ultrasound.
Attention is drawn to the following places, which may be of interest for search:
Disinfection and sterilisation using ultrasonic devices |
If ultrasonic waves are created mechanically, e.g. with a nozzle, classify in C02F 1/34.
This place covers:
Processes for treatment of water, waste water or sewage in which separation is achieved by using centrifugal forces, e.g. hydrocyclones, hydrodynamical separators.
Attention is drawn to the following places, which may be of interest for search:
Centrifugal separators in general |
This place covers:
Centrifugal separation for treating water.
This place does not cover:
Centrifugal separation of sludge | |
Centrifuges |
This place covers:
Devices for removing fatty or oily substances or similar floating material,, e.g. grease traps, oil water separators or oil skimmers
Attention is drawn to the following places, which may be of interest for search:
Separation of liquids | |
Devices for removing oil from open water surfaces | |
Devices in sewers for removing fat and oil from sewage | |
Devices for use in drains leading to the sewer |
Group is at present not used for classification, use C02F 1/40.
This place covers:
Use of resin type ion exchangers for treatment of water, waste water or sewage
Attention is drawn to the following places, which may be of interest for search:
Dishwashers comprising water softeners | |
Ion-exchange in general | |
Washing machines comprising water softeners |
Ion exchange using zeolites and other inorganic ion exchangers should be classified in C02F 1/281 (sorption with inorganic sorbents).
This place covers:
Water treatment processes using membrane separation.
This place does not cover:
Electrodialysis | |
Membrane bioreactor systems | |
Submerged membrane bioreactors | |
Anaerobic membrane bioreactors |
Attention is drawn to the following places, which may be of interest for search:
Membrane separation, devices |
This place covers:
Treatment of water, waste water, sewage by reverse osmosis
Attention is drawn to the following places, which may be of interest for search:
Reverse osmosis processes in general |
This place covers:
Treatment of water, waste water, sewage by nanofiltration
Attention is drawn to the following places, which may be of interest for search:
Nanofiltration processes in general |
This place covers:
Treatment of water, waste water, sewage by ultrafiltration or microfiltration
Attention is drawn to the following places, which may be of interest for search:
Ultrafiltration processes in general | |
Microfiltration processes in general |
This place covers:
Electrochemical methods for treating water, if no electrical current (static electrical field) is used C02F 1/48 applies.
Attention is drawn to the following places, which may be of interest for search:
When classifying in C02F 1/46 the additional symbols under C02F 2201/46 should be used for additional information.
This place covers:
All electrochemical seawater desalination processes not covered by C02F 1/469.
This place covers:
Production of disinfecting metallic ions, e.g. Ag, Cu, by electrolysis.
Attention is drawn to the following places, which may be of interest for search:
Non-electrolytic oligodynamic treatment |
In this place, the following terms or expressions are used with the meaning indicated:
Oligodynamic substances | active substances in very small quantities, used especially to describe the sterilizing effect of some heavy metals against bacteria |
This place covers:
Treatment of water by applying electrical discharges, generally by using high voltages.
This place covers:
Electrolytic devices used for water treatment, for additional details not covered by classes in C02F the symbols C02F 2001/46119 - C02F 2001/46171 , and C02F 2001/46185 - C02F 2001/46195 can be used.
This place covers:
Electrodes for water treatment purposes.
Additional information can be given by using the symbols C02F 2001/46119 - C02F 2001/46166.
This place covers:
Electrolytic cells where the space between anode and cathode is filled with a bed of particles (static or fluidised bed) and electrodes which are themselves comprised of particles.
This place covers:
Production of acidic, oxidising water at the anode and alkaline, reducing water at the cathode (separation of the streams).
If the water is primarily used for oxidation C02F 1/4672 applies. For electrochemical reduction use C02F 1/4676. Additional symbols C02F 2001/46185 - C02F 2001/46195 are available.
This place covers:
Electrochemical production of coagulant, e.g. iron or aluminium ions, usually with dissolution of the electrode.
This place covers:
Electrochemical production of microbubbles for flotation.
Attention is drawn to the following places, which may be of interest for search:
Water treatment by flotation |
This place covers:
Electrochemical production of oxidants (oxygen, ozone, hydroxyl radicals) at the anode for disinfection and oxidation of organic and inorganic substances.
Attention is drawn to the following places, which may be of interest for search:
Creating reactive oxygen species |
This place covers:
Electrochemical production of reducing agents (hydrogen), occurring at the cathode.
This place covers:
Reduction of metals (electroplating) is included in this group.
This place covers:
All processes where an electrical field is the driving force for separating substances in water treatment.
This place covers:
Removing ions from water by capacitive deionisation.
Attention is drawn to the following places, which may be of interest for search:
Capacitors |
This place covers:
Treatment of water, waste water, sewage by electrodialysis
Attention is drawn to the following places, which may be of interest for search:
Electrodialysis processes in general |
This place covers:
Use of an electrodialysis cell wherein one or more of the compartments is filled with ion-exchange material.
Attention is drawn to the following places, which may be of interest for search:
Electrodeionisation processes in general |
This place covers:
Treatment of water, waste water, sewage by using the effect of electro-osmetic flow, i.e. the motion of liquid induced by an applied electrical potential across a porous material such as a capillary tube, membrane or microchannel.
Attention is drawn to the following places, which may be of interest for search:
Electro-osmosis processes in general |
This place covers:
Includes treatment with an electrical field (no electrical current in the water).
This place does not cover:
Water treatment by electrochemical methods |
Attention is drawn to the following places, which may be of interest for search:
Eliminating or preventing deposits, scale prevention | |
Magnetic or electrostatic separation |
This place covers:
Treatment with permanent magnets.
This place covers:
Treatment using electromagnets.
This place covers:
Treatment of water by using high frequency electromagnetic fields, e.g. for reducing scale in pipelines. Frequencies above 500 Hz are considered "high frequency" in the present context.
This place covers:
Water treatment processes where a magnetic field is used for separation (includes removing loaded sorbents from water).
This place covers:
Treatment of water by addition of chemicals and compounds that adversely affect the ability of microorganisms, animals and plants to survive or reproduce.
This place does not cover:
Electrochemical methods for producing oligodynamic substances to disinfect the water | |
Electrochemical disinfection | |
Oxidation with halogens or compounds of halogens |
Attention is drawn to the following places, which may be of interest for search:
In patent documents, the following words/expressions are often used as synonyms:
- EN: disinfect, sterilize, sanitize
- DE: sterilisieren, desinfizieren,
- FR: stériliser, désinfecter, aseptiser
This place covers:
Treatment of water by oligodynamic effect created by the addition of metallic ions of mercury, silver, copper, iron, lead, zinc, bismuth, gold, aluminium.
This place covers:
Processes and related installations or apparatus for water treatment by causing coagulation or flocculation. Crystallisation processes are to be included when used for water treatment.
This place does not cover:
Electrocoagulation |
Attention is drawn to the following places, which may be of interest for search:
Flotation processes | |
Sedimentation | B0D21 |
In this place, the following terms or expressions are used with the meaning indicated:
Coagulation | breaking of the electrostatic repulsion to allow growth of "nuclei". |
Flocculation | growth of "flocs" mostly by addition of separated nuclei. |
In patent documents the following terms are often used:
EN | Coagulation, flocculation, precipitation, agglomeration, weighting, ballast |
DE | Koagulation, Flockung, Fällung, Agglomeration, Beschwerung, ballast |
FR | Coagulation, floculation, précipitation, agglomération, pondération, ballast, lesté. |
This place covers:
Water treatment documents where the invention information relates to the regulation of coagulation and flocculation, or to the way the coagulated or precipitated matter is separated when no other subclass is provided.
This place does not cover:
Control for chemical and physical water treatment | |
Control for biological water treatment |
Attention is drawn to the following places, which may be of interest for search:
Control parameters | |
Control in general |
Use the Indexing Codes under C02F 2209/00 - C02F 2209/445 if applicable.
This place covers:
This group concerns processes for improving the dissolution of additives before coagulation or flocculation is performed.
This place covers:
Water treatment using inorganic coagulants or flocculants.
Inorganic polymers should not receive the C02F 1/56 class or Indexing symbol.
This place covers:
Treament of water by addition of inorganic salts with alkaline character.
This place covers:
Treatment of water in the MAP process, i.e. magnesium ammonium phosphate precipitation process to remove ammonium nitrogen from waste water
This place covers:
Treatment of water by flocculation or precipitation of suspended impurities with the use of natural compounds chemically unmodified and unformulated; e.g. chitosan, bacterial products.
Compounds unmodified and unformulated. Formulations comprising them should be classified in C02F 1/5272.
This place covers:
Treatment of water by flocculation or precipitation of suspended impurities with the use of defined organic compounds and formulations for water treatment, e.g. formulations comprising lignin as coagulant.
This place covers:
Apparatuses and installations comprising devices for water coagulation and precipitation.
This place covers:
Water treatment including the preparation of lime water.
This place covers:
Water treatment by organic compounds comprising phosphorus functional groups.
This place covers:
Water treatment by organic compounds comprising silicon functional groups.
This place covers:
Water treatment by surface active organic compounds.
This place covers:
Water treatment with organic polymers.
Attention is drawn to the following places, which may be of interest for search:
Inorganic polymeric compounds | |
Polymers in general |
This place covers:
Documents related to removal of specific polluting or unwanted compounds from water.
The classes C02F 1/58 - C02F 1/645 should only be used if no other class is applicable, for specifying the compound to be removed the Indexing symbols in the range C02F 2101/00 - C02F 2101/40 should be given. Classification of the method and the apparatus used in C02F is also mandatory.
This place covers:
Processes directed to obtain or avoid a particular pH value or range in water treatment.
Attention is drawn to the following places, which may be of interest for search:
Classify here when invention information concerns pH adjustment. In all other cases involving pH measurement or adjustment use symbols from C02F 1/66 or C02F 2209/06.
This place covers:
Adding specific substances, e.g. vitamins, trace elements or carbon dioxide to water.
Attention is drawn to the following places, which may be of interest for search:
Medicinal water |
This place covers:
Addition of adsorbents to the water for removing oil from water (remediating oil spills).
This place covers:
Water treatment by addition of any molecules forming a complex with a target, regardless their other characteristics or use
In patent documents the following terms are often used:
sequestering, complexing, scavenging, chelating
This place covers:
Water treatment devices for adding chemicals to water in a controlled manner.
Attention is drawn to the following places, which may be of interest for search:
Dosing of halogens in gaseous form |
This place covers:
Water treatment devices for adding chemicals in liquid form.
This place covers:
Water treatment devices for adding chemicals in solid form to water in a controlled manner.
This place covers:
Water treatment devices for adding chemicals to water in a controlled manner exploiting the flow of water which gradually dissolves the product to be dosed. Includes the use of tablets or granular products enclosed in a device.
This place covers:
Water treatment processes wherein pollutants are chemically reduced.
This place does not cover:
Electrochemical reduction processes |
This place covers:
Water treatment processes wherein pollutants are reduced by metallic compounds (in zero valence state).
This place covers:
Water treatment processes wherein pollutants are chemically oxidized.
This place does not cover:
Electrochemical oxidation processes |
This place covers:
Water treatment processes wherein pollutants are oxidized by peroxides.
This place covers:
Water treatment processes wherein pollutants are oxidized by catalytic reactions. Includes the use of heterogeneous catalysts.
Attention is drawn to the following places, which may be of interest for search:
Fenton type oxidation | |
Photocatalysts |
Photocatalysis is classified by combining C02F 1/32 or C02F 1/325 with C02F 1/725 and C02F 2305/10.
This place covers:
Water treatment processes wherein pollutants are oxidized by pure oxygen or oxygen enriched gas.
Attention is drawn to the following places, which may be of interest for search:
Reactive oxygen species, singlet oxygen, OH radical |
This place covers:
Water treatment processes wherein pollutants are oxidized by air.
This place covers:
Water treatment processes wherein pollutants are oxidized by halogens.
This place does not cover:
Electrochemical oxidation using halogens |
This place covers:
Water treatment devices for adding halogens in gaseous form to water in a controlled manner.
Attention is drawn to the following places, which may be of interest for search:
Dosing of substances in general |
This place covers:
Water treatment processes wherein pollutants are oxidized by halogens explicitly different from chlorine, e.g. bromine.
This place covers:
Water treatment processes wherein pollutants are oxidized by ozone.
This place does not cover:
Electrochemical oxidation using ozone |
This place covers:
This group covers processes relating to biological water treatment. Devices are only classified in detail if there is no appropriate, more general place available and if they are clearly related to the water treatment aspect (not universally applicable).
This place does not cover:
Water distributors |
In this place, the following terms or expressions are used with the meaning indicated:
Aerobic | presence of dissolved oxygen |
Anoxic | oxygen not present as dissolved oxygen but in the form of nitrate, sulfate, etc. |
Anaerobic | absence of oxygen |
This place covers:
Processes in which electrochemical treatment and biological treatment are directly combined, e.g. the electrodes being covered by a biofilm or electrodes being directly immersed in an activated sludge tank.
Attention is drawn to the following places, which may be of interest for search:
Electrochemical water treatment in general | |
Electrochemical aeration |
This place covers:
To be used if the control of a biological water treatment process is the main invention.
This place does not cover:
Control of physical and chemical water treatment processes | |
Control of flocculation or precipitation processes |
Attention is drawn to the following places, which may be of interest for search:
Control parameters | |
Control in general |
Symbols for the specific controlled parameters should be used if possible (C02F 2209/00-C02F 2209/445).
This place covers:
All aerobic water treatment processes, which are not covered by the following more specific groups.
This place covers:
Trickling filters, i.e. biofilm reactors where the filter medium is not submerged in the water to be treated.
This place covers:
Devices for distributing the water over the filter such as rotating arms, sprinklers.
This place covers:
Filters using the soil as filter medium, the filters can be arranged in a column above the ground.
This place covers:
This class contains processes which use larger biofilm carriers which are in movement in the reactor. Rotating biological contactors are classified in C02F 3/082.
Not for smaller biofilm carriers such as used in fluidised bed reactors. These should be classified in C02F 3/085. The carrier could be classified in C02F 3/10 and subgroups.
This place covers:
Packings, fillings and grids used as biofilm carrier (shape, arrangement, material).
Attention is drawn to the following places, which may be of interest for search:
Separating processes characterised by the packing of the sorbent material | |
Packed scrubbers | B01D47/54 |
Packing elements |
This place covers:
Biological treatment of water, waste water or sewage by aerobic processes using arrangement of a plurality of tanks, packings, grids, disks in stacks, arrays.
This place covers:
Membrane acting as support for the biofilm (not primarily for separation or aeration).
In case the membrane is used primarily for separating activated sludge or other substances from water C02F 3/1268, C02F 3/1273 and C02F 3/2853 should be used.
This place covers:
Textiles acting as biofilm support.
This place covers:
Granular carrier used as a packing or filling.
This place covers:
Packing, filler or carrier defined by the chemical composition, e.g. carbon based, inorganic, gels, polymers, etc.
This place covers:
This group comprises all aerobic processes in which the microorganisms are present in the form of an activated sludge, i.e. located on or in flocs which are suspended in the water to be treated.
This place covers:
The treatment steps are carried out in different treatment tanks.
Attention is drawn to the following places, which may be of interest for search:
Sludge treatment |
Treatment with several steps carried out in a single tank should be classified in C02F 3/1263 (SBR).
This place covers:
Phosphate removal by chemical precipitation in combination with activated sludge treatment, e.g. by dosing salts of iron or aluminium directly into the activated sludge tank.
Attention is drawn to the following places, which may be of interest for search:
Precipitation and flocculation | |
Phosphorous compounds |
If precipitation and separation is performed as a separate treatment, e.g. after the clarifier, C02F 1/5245 should be used.
This place covers:
Reduction of surplus sludge by heating, ultrasonic treatment, oxidation carried out in a side stream (e.g. return sludge stream).
This place covers:
Using adsorbents or inert solids in suspension in the activated sludge tank, e.g. activated carbon powder or zeolites. The aim of the use of the adsorbents is to adsorb harmful substances or to improve the settleablilty of the flocs rather than to act as a carrier material.
This class is not used for classifying fluidised bed reactors. These should be classified in C02F 3/085.
This place covers:
Small wastewater treatment plants such as upgraded septic tanks and other compact devices for use in small communities, hotels or single houses.
This place covers:
Extended aeration with simultaneous sludge stabilisation.
This place covers:
Sequencing batch reactors (SBR) for carrying out several treatment steps batchwise in a single tank.
This place covers:
Membrane bioreactor systems for aerobic treatment of water.
Attention is drawn to the following places, which may be of interest for search:
Membrane processes | |
Electrodialysis | |
Anaerobic membrane treatment | |
General membrane treatment |
If the membrane is used to further purify the wastewater after a clarifier or other liquid-solid separation C02F 1/44 should be used.
This place covers:
The membrane module is submerged in the activated sludge suspension (treatment tank).
This place covers:
Mixing devices for keeping the activated sludge suspended.
Attention is drawn to the following places, which may be of interest for search:
General mixing |
This place covers:
Activated sludge treatment using mechanical surface aeration.
This place covers:
Aeration in activated sludge processes whereby diffusers are used for aeration.
Attention is drawn to the following places, which may be of interest for search:
Dispersing gas in a liquid |
This place covers:
Circulation of the activated sludge suspension is achieved by injecting air (mammoth-pump effect).
Attention is drawn to the following places, which may be of interest for search:
Dispersing gas in a liquid |
This place covers:
Processes using very deep treatment tanks for improving oxygen transfer.
This place covers:
Anaerobic treatment of wastewater.
Attention is drawn to the following places, which may be of interest for search:
Anaerobic treatment of sludge |
Combined aerobic and anaerobic processes (Bio-P removal, nitrogen removal) are classified in C02F 3/30 - C02F 3/308.
In this place, the following terms or expressions are used with the meaning indicated:
Aerobic | presence of dissolved oxygen |
Anoxic | oxygen not present as dissolved oxygen but in the form of nitrate, sulfate, etc. |
Anaerobic | absence of oxygen |
This place covers:
Anaerobic biofilm processes using reactors with fixed beds, fluidised beds or membranes as biomass carrier.
This place covers:
Biological treatment of water, waste water or sewage with several treatment sets batchwise in a single anaerobic tank
Attention is drawn to the following places, which may be of interest for search:
Aerobic SBR processes |
This place covers:
Biological treatment of water, waste water or sewage by anaerobic digestion processes using a reactor with fluidized bed, the water passing through a granular solid material at high enough velocity to suspend the solid
Attention is drawn to the following places, which may be of interest for search:
Aerobic fluidised bed processes | |
Chemical or physical processes and apparatus conducted in the presence of fluids and solid particles |
This place covers:
Reactors containing an anaerobic sludge bed, internal separators and gas collectors.
This place covers:
Membrane bioreactors for anaerobic processes.
Attention is drawn to the following places, which may be of interest for search:
Membrane processes | |
Electrodialysis | |
Membrane bioreactor systems | |
Submerged membrane bioreactors | |
General membrane treatment |
This place covers:
Treatment with two or more anaerobic steps (no oxygen, nitrate, nitrite available).
Attention is drawn to the following places, which may be of interest for search:
Aerobic multi-step processes |
This place covers:
Internal circulation is achieved by the gas bubbles created during the fermentation process (carbon dioxide, methane).
This place covers:
Biological treatment of water, waste water or sewage by anaerobic digestion processes with two story septic tank combination, i.e. Imhoff tank: simple reactors, precursors of the UASB reactors.
This place covers:
Processes which are characterised by a combination of anaerobic, anoxic and aerobic process steps, particularly for the biological removal of phosphorous and nitrogen.
In this place, the following terms or expressions are used with the meaning indicated:
Aerobic | presence of dissolved oxygen |
Anoxic | oxygen not present as dissolved oxygen but in the form of nitrate, sulfate, etc. |
Anaerobic | absence of oxygen |
This place covers:
No separate reactors used for the anaerobic, anoxic and aerobic treatment steps.
This place covers:
Biological nitrogen removal by means of combined nitrification / denitrification treatment.
This place does not cover:
Biological phosphorous removal |
This place covers:
Biological nitrification processes, i.e. biological processes for oxidising ammonia to nitrite and/or nitrate.
This place covers:
Biological denitrification processes, i.e. biological processes for reducing nitrite and nitrate to elementar nitrogen.
This place covers:
Biological processes for reducing phosphorous.
Attention is drawn to the following places, which may be of interest for search:
Combination of chemical precipitation of phosphorous and activated sludge treatment |
This place covers:
Biological treatment of water, waste water or sewage by using any plants or any animals, e.g. constructed wetlands, worms, algae, protozoa
This place covers:
Biological treatment processes using special types of microorganisms (specific species or consortia which are identified and not commonly used).
Attention is drawn to the following places, which may be of interest for search:
Biotechnology, microorganisms in general |
This place covers:
Groups of bacteria which are specified and achieve a synergistic effect.
This place covers:
Specific enzymes produced by microorganisms. Also for the use of the pure enzymes.
This place covers:
Dosing of the bacteria in a specific form, e.g. lyophilised, as a powder, together with nutrients) or dosing at a specific location (e.g. in a sidestream).
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein hardness is eliminated by precipitation before it may result in adverse effects.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein hardness is eliminated by precipitation using phosphates before it may result in adverse effects.
This place does not cover:
Softening using calcium compounds |
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein hardness is eliminated by precipitation using calcium compounds before it may result in adverse effects.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale.
Attention is drawn to the following places, which may be of interest for search:
Use of complexing agents |
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein mineral agents are used.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein condensed phosphates are used.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances not provided for in the following groups are used.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances not provided for in the following groups are used in combination with inorganic substances.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances comprising nitrogen are used.
This place does not cover:
Softening using organic substances containing phosphorous |
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances comprising nitrogen are used in combination with inorganic substances.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances comprising phosphorus are used.
This place covers:
This group covers processes and apparatus relating to chemical water treatment to prevent clogging or the presence of hard deposits on apparatus in contact with water, wherein the adverse effects of hardness are avoided by preventing it to form scale or by removing existing scale wherein organic substances comprising phosphorus are used in combination with inorganic substances.
This place covers:
Aeration of stretches of natural waters, like rivers, lakes or ponds. Devices for such use such as boats or fixed installations.
Attention is drawn to the following places, which may be of interest for search:
Dispersing gas in a liquid |
Treatment other than aeration should be classified using the relevant classes in combination with C02F 2103/007.
This place covers:
Treatment operations, carried out in a defined order in three or more different treatment stages, each stage occurring in a separate location, e.g. apparatus, reactor or compartment.
Attention is drawn to the following places, which may be of interest for search:
Activated sludge multistep treatment | |
Anaerobic multistep treatment | |
Multistage treatment |
Group C02F 9/00 does not cover treatments, where the essential characteristic resides in an individual step of the treatment, which treatments are covered by groups C02F 1/00 - C02F 7/00. Any individual step of a multistep treatment which is considered to represent information of interest for search, may also be classified in one or more of groups C02F 1/00 - C02F 1/56 or C02F 1/66 - C02F 7/00 as "additional information".
This place covers:
Processes incorporating several treatment steps in a compact, transportable device in the size of a small cupboard, e.g. filter units on wheels, laboratory devices for ultrapure water production or dispensers comprising advanced water treatment.
Attention is drawn to the following places, which may be of interest for search:
Small transportable filters | |
Household type filters |
This place covers:
In the present context sludge is defined as an aqueous suspension of solids resulting from water treatment processes and having a solids content of more than 0.2% (2 g/L).
This place covers:
Extraction of contaminants from sludge.
Attention is drawn to the following places, which may be of interest for search:
Extraction for soil reclamation |
This place covers:
Immobilisation or removal of toxic compounds.
This place covers:
Solidification of the sludge, e.g. by vitrification.
Attention is drawn to the following places, which may be of interest for search:
Reclamation of contaminated soil by vitrification |
This place covers:
Aerobic and anaerobic biological sludge treatment.
Attention is drawn to the following places, which may be of interest for search:
Biological reclamation of contaminated soils |
This place covers:
Comprises all anaerobic processes for sludge treatment (mostly carried out in digesters).
This place covers:
Oxidation of sludge including thermal oxidation such as incineration.
Attention is drawn to the following places, which may be of interest for search:
Incinerators for burning sludge from water treatment installations | |
Incineration of waste liquors |
This place covers:
Wet air oxidation is defined as oxidation under elevated temperatures and pressure (p >> 100 bar, T >> 100°C).
Exceptionally, treatment of wastewater can also be classified here if this is the most appropriate class.
This place covers:
The supercritical state for water is defined as p > 221 bar, T > 374°C.
This place covers:
Thermal treatment of sludge under reducing conditions (absence of oxygen or other oxidants).
Attention is drawn to the following places, which may be of interest for search:
Destructive distillation of solid carbonaceous materials for production of gas, coke, tar |
Attention is drawn to the following places, which may be of interest for search:
Drying solid materials or objects by removing liquid therefrom |
Thermal drying is classified in the head group, if the sludge is heated for other purposes, C02F 11/18 and subgroups should be used.
This place covers:
Extraction of water from sludge using centrifuges, hydrocyclones or other hydrodynamic separators using centrifugal forces.
Attention is drawn to the following places, which may be of interest for search:
Centrifugal separation of water, waste water or sewage | |
Centrifugation of aqueous suspensions | |
Centrifuges | |
Apparatus using free vortex flow |
In this place, the following terms or expressions are used with the meaning indicated:
Batch process | A batch process is a process in which the feed is not introduced in a continuous stream, but as a series of discrete charges, each of which may be processed over one or more states of treatment. |
This place covers:
Drying of sludge by heating includes direct or indirect heating. The actual purpose of treatment is to use heat to dry the sludge.
Thermal drying is classified in this group. If the sludge is heated for conditioning, then classification is made in group C02F 11/18 and subgroups thereof or if the sludge is treated by pyrolysis, then classification is made in group C02F 11/10. This group should be used for cases where drying by heating is the actual purpose of the treatment. If heating is a side-effect of treatment, classification is made in other relevant places, e.g. C02F 11/15.
This place covers:
De-watering, drying or thickening of sludge by the addition of chemical agents, e.g. flocculants added during or before the dewatering process.
In groups C02F 11/14 - C02F 11/148, if inorganic and organic substances are added independently in different processes steps, the group C02F 11/143 or subgroup thereof, along with C02F 11/147 should be used. If inorganic and organic substances are added in the same treatment step, the group C02F 11/148 should be used.
Addition of organic and inorganic compounds having a synergistic effect to the same treatment step. Coated compounds comprising inorganic and organic functions are classified in this group.
This place covers:
De-watering, drying or thickening of sludge by treatment with electric, magnetic or electromagnetic fields; or with ultrasonic waves, e.g. by treatment with electromagnetic waves or ultrasonic waves in order to disrupt or lyse cellular material, or break cell walls of cells in the sludge, or transform bound water in the sludge into free water.
This place does not cover:
Using electromagnetic or ultrasonic waves |
This place covers:
De-watering or drying of sludge with drying or composting beds, e.g. several drainage layers for the separation of the solid from the liquid fraction of sludge.
Attention is drawn to the following places, which may be of interest for search:
Composting of household refuse |
This place covers:
Thermal sludge conditioning other than drying.
This place does not cover:
Sludge treatment by pyrolysis |
Attention is drawn to the following places, which may be of interest for search:
Thermal conditioning of soil |
Drying, dewatering of sludge is classified in C02F 11/12.
This place covers:
Heating of sludge above 60°C for the purpose of disinfection.
This place covers:
The nature of the contaminant, i.e. chemical composition or class of chemical is specified here.
This place covers:
The nature of the water to be treated such as wastewater from specific origin or pure water for specific applications.
This place covers:
Constructional details related to the apparatus used for water treatment.
This place covers:
Constructional details related to the apparatus used for biological water treatment.
This place covers:
Controlling or monitoring parameters in water treatment. Details relating to the measuring device and controller used for controlling or monitoring the parameters.
This place covers:
General aspects of water treatment, such as fluid flow conditions, e.g. flow arrangements, pressure conditions.
This place covers:
Specific treatment goals, e.g. disinfection, corrosion inhibition, removal of agents after treatment.
This place covers:
Use of specific compounds in water treatment, e.g. surfactants, nutrients, nanoparticles.
This place covers:
Location of water treatment or water treatment device, e.g. as part of a bottle, pitcher or mounted on a faucet.