DESC:METHOD AND SYSTEM FOR ULTRAVIOLET LIGHT-BASED AIR PURIFICATION
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of the Indi-an Provisional Patent Application title ‘HIGH INTENSITY ULTRAVIOLET (UV) LIGHT DISINFECTION AND GRAPHENE BASED AIR PURIFICATION UNIT AND SYSTEM THEREOF’ application number 202041034960, filed in the Indian Patents Office on August 13, 2020. The specification of the above reference patent application is incorporated herein by reference in its entirety.

A) TECHNICAL FIELD
[0002] The embodiments of the present invention are generally related to an air purification system. The embodiments of the present invention are particularly related to an ultra-violet light-based air purification systems. The embodiments of the present invention are more particularly related to a method and system for air purification using a high intensity ultraviolet light to kill pathogens present in the air and also remove harmful gases from air.

B) BACKGROUND OF THE INVENTION
[0003] Air pollution is a long - standing problem, which increases day by day. Dust, smoke and pollen are the major sources of air pollution. Such contaminants create long term health problems, sometimes leading to death. Microorganisms such as bacteria, fungi and viruses also contribute to air related health issue. At present, the world is fighting against a new pathogen, a coronavirus known as SARS – CoV – 2. World Health Organization (WHO) has declared COVID – 19, the dis-ease caused by this new pathogen as a pandemic and the whole world is fighting against it.
[0004] Currently known air purifiers are effective for specific type of pollutants and do not provide a comprehensive air purification efficiency. Ultraviolet (UV) radiation is known for its capability of inactivating microorganisms such as viruses, fungi, bacteria and other airborne pathogens. Also, air filters such as high efficiency particulate air (HEPA) are highly effective for removal of particles up to 0.3 microns.
[0005] The existing air purification systems are generally based on high efficiency particulate air HEPA filters alone and in some cases along with an activated carbon filter bed. HEPA filters are used for particulate removal and activated carbon is used for removal of gaseous pollutants. However, activated carbon has its efficiency limitations. Also, existing air purification systems are not effective against airborne pathogens.
[0006] The air which we breathe should be clean and free from harmful pollutants, as it is one of the most vital components required for sustaining life on Earth. Hence, an efficient air purifier is required for effectively removing particulate matter, microorganisms and harmful chemical pollutants such as volatile organic compounds (VOCs), sulphur oxides (SOx), nitrogen oxides (NOx), and the like.
[0007] Hence there is a need for an efficient air purification system that eliminates pollutants and microorganisms and provides a comprehensive air purification efficiently.
[0008] The above-mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.

C) OBJECT OF THE INVENTION
[0009] The prime object of the present invention is to provide an air purifier system based on a high intensity ultraviolet (UV) light-based air purification system and a method thereof.
[0010] Another object of the present invention is to provide a high intensity ultraviolet (UV) light-based air purifier system which inactivates air-borne and aerosolized pathogens present in the air in an indoor environment.
[0011] Yet another object of the present invention is to provide an air purifier system and method that uses a high intensity UV radiation (or light or rays) with a wavelength in a range of 100-280 nm to inactivate the pathogens present in the air.
[0012] Yet another object of the present invention is to provide an air purifier system that uses a high efficiency particulate air (HEPA) filter for particulate material removal.
[0013] Yet another object of the present invention is to provide an air purifier system which uses High Efficiency Particulate Air (HEPA) filter for particulate material removal up to 0.3 microns.
[0014] Yet another object of the present invention is to provide an UV-based air purifier system comprising one or more graphene based active beds containing graphene-based materials such as, but not limited to, graphene oxide, functionalized graphene oxide, (3D) graphene, graphene nanoplatelets, and graphene ceramic composites.
[0015] Yet another object of the present invention is to provide an air purifier system comprising at least one graphene based active bed containing graphene-based materials with a concentration of 0.001g/cc to 1.0g/cc, for maximum filtration efficiency and minimum pressure drop created by the graphene based active bed.
[0016] Yet another object of the present invention is to provide an air purifier system comprising one or more graphene based active beds for removing volatile organic compounds (VOC) and harmful gases such as sulphur oxides (SOx), nitro-gen oxides (NOx), carbon dioxide, carbon mono oxide, benzene, toluene, ammonia, hexane, formaldehyde, mercaptan, xylene and other similar gases.
[0017] Yet another object of the present invention is to provide an UV based air purifier system comprising one or more graphene based active beds placed over the UV disinfection chamber such that any ozone or foul smelling compounds such as thiols, mercaptans created due to the UV light disinfection are removed by graphene materials based active beds.
[0018] Yet another object of the present invention is to provide an air purifier system comprising three-units design of UV based air purifier in which, a first unit contains a HEPA filtration unit with a plurality of vents for inlet of air; a second unit comprises a disinfection unit comprising a plurality of UV lamps for per-forming a UV based disinfection; and the third unit is a pollutant removal unit that comprises at least one graphene based active bed for removing pollutants from the disinfected air, and a plurality of vents for air outlet.
[0019] Yet another object of the present invention is to provide an UV based air purifier system comprising three-units design in which, the fan is positioned either at the top of the first unit or at the bottom of the third unit suitably.
[0020] Yet another object of the present invention is to provide an UV based air purifier system in which a user-friendly removable container is provided in the first unit for easy replacement of the HEPA filter.
[0021] Yet another object of the present invention is to provide an UV based air purifier system in which a removable container is provided in the third unit for easy replacement of the graphene based active beds.
[0022] Yet another object of the present invention is to provide an UV based air purifier system comprising either axial or centrifugal fan of appropriate/suitable air flow rate for proper and required air circulation.
[0023] Yet another object of the present invention is to provide an UV based air purifier system comprising a power switch and a switch to turn on/ off the UV sources, such as UV lamps.
[0024] Yet another object of the present invention is to provide an UV based air purifier system with a control panel for regulating or adjusting the UV disinfection time duration.
[0025] Yet another object of the present invention is to provide an UV based air purifier system comprising one or more UV radiation sources, such as, UV lamps to ensure UV irradiation of 1 to100 mJ/cm2 in the disinfection unit.
[0026] Yet another object of the present invention is to provide an UV based air purifier system comprising one or more UV lamps arranged horizontally in a crisscross pattern to provide maximum contact of air with UV radiations in the dis-infection unit.
[0027] Yet another object of the present invention is to provide an UV based air purifier system comprising one or more UV lamps to ensure high intensity UV rays in the disinfection unit.
[0028] Yet another object of the present invention is to provide an UV based air purifier system comprising non-UV transmitting material such as polycarbonate, polymethylmethacrylate or a combination thereof.
[0029] Yet another object of the present invention is to provide an UV based air purifier system comprising a UV reflective material such as stainless steel, aluminium, silver, aluminized polymer films, silvered polymer reflectors or a combination thereof coated on the interior walls of the second unit.
[0030] Yet another object of the present invention is to provide an UV based air purifier system in which the intensity of the UV radiations is controlled depending on the requirement to inactivate the pathogen.
[0031] Yet another object of the present invention is to provide an air purifier system with a desired disinfection time in an indoor environment.
[0032] Yet another object of the present invention is to provide an UV based air purifier system in which power flux from the UV lamps, a distance between the UV lamps, a time required by the air to either stay or pass through, are optimized to inactivate the pathogen.
[0033] Yet another object of the present invention is to provide an UV based air purifier system comprising a safety system to prevent UV lamps from overheating.
[0034] Yet another object of the present invention is to provide an UV based air purifier system in which the safety system automatically cuts off the power of UV lamps after a pre-set time interval based on the size of the room, and volume of the air inside the room to be disinfected.
[0035] Yet another object of the present invention is to provide an UV based air purifier system in which the safety system allows a 50% of the total UV lamps in the air purifier system to turn on/off alternatively in a present or desired time period
[0036] Yet another object of the present invention is to provide an UV based air purifier system for use in bedrooms, shops, grocery marts, retail outlets, hospitals, households, offices in order to inactivate any pathogens present in the air.
[0037] These and other objects and advantages of the embodiments herein will become readily apparent from the following detailed description taken in con-junction with the accompanying drawings.

D) SUMMARY OF THE INVENTION
[0038] The following details present a simplified summary of the embodiments herein to provide a basic understanding of the several aspects of the embodiments herein. This summary is not an extensive overview of the embodiments here-in. It is not intended to identify key/critical elements of the embodiments herein or to delineate the scope of the embodiments herein. Its sole purpose is to present the concepts of the embodiments herein in a simplified form as a prelude to the more detailed description that is presented later.
[0039] The other objects and advantages of the embodiments herein will be-come readily apparent from the following description taken in conjunction with the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without de-parting from the spirit thereof, and the embodiments herein include all such modifications.
[0040] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
[0041] The various embodiments herein provide an air purifier system and method for purifying air through a multi-stage air purification process. The air purifier system and method provided herein use 360 degrees of high intensity ultraviolet (UV) rays disinfection and a graphene material-based filtering for inactivating pathogens for disinfecting the air. The embodiments of the present invention provide an air purifier system based on a high intensity ultraviolet (UV) radiation which inactivates air-borne and aerosolized pathogens present in the air in an indoor environment. The embodiments of the present invention also provide the air purifier system which uses UV radiation in a range of 100–280 nm wavelength to inactivate the pathogens present in the air.
[0042] According to an embodiment of the present invention, an air purifier system is disclosed. According to an embodiment of the present invention, the air purifier system includes at least one high efficiency particulate air filtration unit (HEPA filtration unit), at least one disinfection unit coupled to the HEPA filtration unit, and at least one pollutant removal unit coupled to the disinfection unit. The HEPA filtration unit includes at least one HEPA filter bed. The HEPA filtration unit extracts air from external atmosphere and performs a HEPA filtration. The disinfection unit includes a plurality of UV radiations sources, such as for example, UV lamps, disposed in a crisscross arrangement. In an alternate embodiment, other form of UV sources known in the art may also be used for this purpose. The disinfection unit receives the HEPA filtered air and performs a 360 degrees UV based disinfection using the plurality of UV lamps, thereby generating disinfected air. The pollutant removal unit is configured to remove harmful gaseous pollutants from the dis-infected air and for releasing purified air to an indoor environment. The pollutant removal unit includes at least one graphene-material based active bed for filtering harmful gaseous pollutants.
[0043] According to an embodiment of the present invention, the HEPA filtration unit includes a first plurality of vents for inlet of air and the pollutant removal unit comprises a second plurality of vents for outlet of purified air. According to an embodiment of the present invention, the pollutant removal unit comprises a fan for circulating purified air.
[0044] According to an embodiment of the present invention, the air purifier system includes one or more switches, a main power switch and a switch to turn ON/ OFF the plurality of UV lamps.
[0045] According to an embodiment of the present invention, the disinfect-ant unit includes an inner surface made of a UV reflective material and an outer sur-face made of a non-UV transmitting material. The UV reflective material of the inner surface and the non-UV material of the outer surface restricts UV rays from the plurality of UV lamps within the disinfectant unit by reflecting the UV rays and facilitates 360 degrees of disinfection within the disinfectant unit.
[0046] According to an embodiment of the present invention, an intensity of the UV rays is controlled depending on the requirement and activity level of pathogens to inactivate the pathogen.
[0047] According to an embodiment of the present invention, the air purifier system includes a control panel to control a time duration for UV radiation-based disinfection.
[0048] According to an embodiment of the present invention, the control panel includes at least one light emitting diode (LED) for indicating a switch the ON/ OFF status of the air purifier system 100 and of the UV lamps. A counter is provided and configured to count a number of days the HEPA filtration unit is active or operational, and wherein the counter begins counting upon the depletion level of the at least one HEPA filter bed reaching below a predetermined threshold level, and wherein the predetermined threshold level is indicated by a manufacturer.
[0049] According to an embodiment of the present invention, a method of air purification is provided. The method includes extracting/receiving air from a first plurality of vents of a HEPA filtration unit of an air purifier system. The method also includes filtering the air through at least one HEPA filter bed provided in the HEPA filtration unit for removing dust particles and particulate matter. The method also includes performing a 360 degrees of disinfection by exposing the air to a UV radiation in a disinfection unit coupled to the HEPA filtration unit for disinfecting the air by inactivating pathogens, wherein the disinfection unit comprises a plurality of UV lamps disposed in a crisscross arrangement and an inner surface made of a UV reflective material for facilitating the 360 degrees of disinfection by reflecting the UV radiation within the disinfection unit. The method also includes passing the disinfected air through a graphene based active bed of a pollutant removal unit coupled to the disinfectant unit by extracting the disinfected air through a fan comprised in the pollutant removal unit, for removing pollutants from the disinfected air and generating a purified air. The method also includes releasing the purified air out of the air purifier system through a second plurality of vents associated with the pollutant removal unit.
[0050] According to an embodiment of the present invention, the step of per-forming the 360-degree disinfection includes optimizing at least one of: a power flux from the plurality of UV lamps, a distance between the plurality of UV lamps, and a time required by the air to stay or pass through the air purifier system, to inactivate the pathogens.
[0051] According to an embodiment of the present invention, the method al-so includes preventing overheating of the plurality of UV lamps by automatically cutting off the power of the plurality of UV lamps after a lapse of a pre-defined time duration of operation of the plurality of UV lamps, wherein the pre-defined time du-ration is set based on a size of the indoor environment to be disinfected.
[0052] According to an embodiment of the present invention, the method includes preventing overheating of the plurality of UV lamps by turning ON, using a safety system, a first set of UV lamps from among the plurality of UV lamps for a pre-defined time interval and turning OFF the first set of UV lamps and turning ON a second set of UV lamps from among the plurality of UV lamps after the pre-defined time interval.
[0053] According to an embodiment of the present invention, the safety system toggles between the first set of UV lamps and the second set of UV lamps until the air purifier system is switched off from a main power line, and the safety system is operable to selectively control the plurality of UV lamps upon the air purifier system being operated beyond a predetermined time duration.
[0054] According to an embodiment of the present invention, the method includes turning OFF the plurality of UV lamps upon completion or interruption of a disinfection cycle.
[0055] According to an embodiment of the present invention the pre-defined time interval is set based on a size of the indoor environment and a volume of the air inside the indoor environment to be disinfected.
[0056] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become ap-parent by reference to the drawings and the following detailed description
[0057] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments here-in without departing from the spirit thereof, and the embodiments herein include all such modifications.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0058] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the ac-companying drawings in which:
[0059] FIG. 1 illustrates an isometric view of an ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0060] FIG. 2 illustrates a high efficiency particulate air (HEPA) filter unit of ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0061] FIG. 3 illustrates a vertical sectional view of a disinfectant unit of the ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0062] FIG. 4A illustrates a side sectional view of a pollutant removal unit of the ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0063] FIG. 4B illustrates an enlarged view of a front panel of the pollutant removal unit in the ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0064] FIG. 4C illustrates an exploded perspective view of the pollutant removal unit of ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0065] FIG. 5 illustrates a flow chart explaining a method of air purification using ultra-violet radiation-based air purifier system, according to one embodiment of the present invention.
[0066] Although the specific features of the embodiments herein are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the embodiments herein.
F) DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0067] In the following detailed description, a reference is made to the ac-companying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0068] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0069] The various embodiments herein provide an air purifier system and method for purifying air based on a multi-stage purification using 360 degrees of high intensity ultraviolet (UV) rays-based disinfection and a graphene material-based filtering. The embodiments of the present invention provide a high intensity Ultraviolet (UV) based air purifier system which inactivates air-borne and aerosolized pathogens present in the air in an indoor environment such as a closed room environment. The embodiments of the present invention also provide an UV based air purifier system which uses UV radiation in a range of 100–280 nm wavelength to inactivate the pathogens present in the air.
[0070] According to an embodiment of the present invention, an air purifier system is disclosed. According to an embodiment of the present invention, the air purifier system includes a high efficiency particulate air filtration unit (HEPA filtration unit), a disinfection unit coupled to the HEPA filtration unit, and a pollutant removal unit coupled to the disinfection unit. The HEPA filtration unit extracts air from external atmosphere and performs a HEPA filtration. The disinfection unit includes a plurality of UV lamps disposed in a crisscross arrangement, for receiving the HEPA filtered air and for performing a 360 degrees UV based disinfection using the plurality of UV lamps to generate a disinfected air. The pollutant removal unit is configured to remove harmful gaseous pollutants from the disinfected air and for releasing purified air through an outlet. The pollutant removal unit includes at least one graphene-material based active bed for filtering harmful gaseous pollutants.
[0071] According to an embodiment of the present invention, the HEPA filtration unit includes a first plurality of vents for inlet of air and the pollutant removal unit comprises a second plurality of vents for outlet of purified air. According to an embodiment of the present invention, the pollutant removal unit comprises a fan for circulating purified air.
[0072] According to an embodiment of the present invention, the air purifier system includes a power cord to be connected to an electrical socket to power the air purifier system.
[0073] According to an embodiment of the present invention, the air purifier system includes one or more switches, a main power switch and a switch to turn ON/ OFF the UV lamps.
[0074] According to an embodiment of the present invention, the disinfect-ant unit includes an inner surface made of a UV reflective material and an outer sur-face made of a non-UV transmitting material. The UV reflective material of the inner surface and the non-UV material of the outer surface restricts UV rays from the plurality of UV lamps within the disinfectant unit by reflecting the UV rays and facilitates 360 degrees of disinfection within the disinfectant unit.
[0075] According to an embodiment of the present invention, the air purifier system includes a control panel to control a time duration for UV radiation-based disinfection.
[0076] According to another aspect of the present invention, a method of air purification is provided. The method includes extracting air from a first plurality of vents of a HEPA filtration unit of an air purifier system. The method also includes filtering the air through a HEPA filter bed comprised in the HEPA filtration unit for removing dust particles and particulate matter by the HEPA filter. The method also includes performing a 360 degrees disinfection by exposing the air to a UV radiation in a disinfection unit coupled to the HEPA filtration unit for disinfecting the air by inactivating pathogens, wherein the disinfection unit comprises a plurality of UV lamps disposed in a crisscross arrangement and an inner surface made of a UV reflective material for facilitating the 360 degrees of disinfection by reflecting the UV radiation within the disinfection unit. The method also includes passing the disinfected air through a graphene based active bed of a pollutant removal unit coupled to the disinfectant unit for removing pollutants from the disinfected air and generating a purified air. The method also includes releasing the purified air out of the air purifier system through a second plurality of vents associated with the pollutant removal unit. The purified air is circulated using a fan of the pollutant removal unit.
[0077] The various embodiments of the present invention provide a high intensity Ultraviolet (UV) based air purifier system which inactivates air-borne and aerosolized pathogens present in the air in an indoor environment. The embodiments of the present invention also provide an UV based air purifier system which uses UV radiation in a range of 100–280 nm wavelength to inactivate the pathogens present in the air.
[0078] According to one embodiment of the present invention, a system for disinfection of air inside the indoor environment from pathogens such as airborne viruses, airborne bacteria, fungal spores, coronaviruses and harmful toxic gases and particulate matter is provided. The system comprises a multiple units made of non – UV transmitting material such as, but not limited to, polymethyl methyl acrylate (PMMA), polycarbonate (PC) or a combination thereof. The air is extracted from the HEPA filtration unit that constitutes a bottom most unit from the indoor environment. The air is extracted into the HEPA filtration unit using suction by a fan placed either at the top or at the bottom of the pollutant removal unit and the air is passed through at least one HEPA filter bed of the HEPA filtration unit. The air is subsequently exposed to UV radiation in the disinfection unit and subsequently the air is passed through at least one graphene based active bed in the pollutant removal unit to generate purified air. The purified air is released into the indoor environment external to the air purifier system from a plurality of vents provided on the top of the pollutant removal unit.
[0079] According to one embodiment of the present invention, the UV lamps utilized in the air purifier system emit radiations in range from about 100 to 280 nano meters (nm) which provides sufficient energy for the disruption of deoxyribonucleic acid DNA or ribonucleic acid (RNA) structure of the pathogens and other airborne pathogens rendering them inactive.
[0080] According to one embodiment of the present invention, the HEPA filter is positioned as the bottom most unit of the air purifier system to facilitate removal of dust, pollen and any other particulate matter up to 0.3 microns.
[0081] According to one embodiment of the present invention, one or more graphene based active beds are utilized for the removal of toxic gases such as but not limited to, sulphur oxides (SOx), nitrogen oxides (NOx), carbon di oxide, carbon mono oxide, benzene, toluene, ammonia, hexane, formaldehyde, mercaptan, xylene and other similar gases. The graphene based active beds include graphene or its derivatives such as but not limited to graphene oxide, functionalized graphene oxide, 3D graphene, graphene nanoplatelets, and graphene ceramic composites.
[0082] According to one embodiment of the present invention, the graphene - based active beds are placed over the disinfection unit to block any ozone gas which is harmful to living beings or to block any type of foul smelling compounds such as thiols, mercaptans created due to the UV light disinfection being released into the air.
[0083] According to one embodiment of the present invention, the density of the graphene materials based active beds is 0.001 g/cc – 1.0 g/cc. A suitable density of the graphene materials based active beds is chosen so to achieve maximum removal of harmful toxic gases and also to minimize the pressure drop of air created inside the air purifier by the graphene materials based active beds.
[0084] According to one embodiment of the present invention, the internal surface of the disinfection unit is made from the UV reflective materials such as, but not limited to, aluminium, stainless steel, aluminized polymer films, silvered polymer films or a combination thereof. The UV reflective materials used in the internal surface enables the air column inside the disinfection unit to be exposed to enough energy for inactivating viruses.
[0085] According to one embodiment of the present invention, one or a plurality of UV lamps is utilized inside the disinfection unit to maintain for example, 1 – 100 milli joules per square centimetre (mJ/cm2) of UV radiation inside the disinfection unit. The plurality of UV lamps are arranged horizontally in the disinfection unit in a crisscross pattern to provide a maximum contact of air column with UV radiations for inactivation of the viruses.
[0086] According to one embodiment of the present invention, an axial or a centrifugal fan of appropriate air flow rate is utilized for maximum disinfection coverage. The air purifier system takes a minimum of 10 minutes to disinfect air in the indoor environment depending upon the size of the indoor environment.
[0087] According to one embodiment of the present invention, to allow for HEPA filter replacement after its specified life is over, a consumer-friendly removable container is provided in the HEPA filtration unit.
[0088] According to one embodiment of the present invention, to allow for replacement of the graphene material based active beds after their specified life is over, a consumer-friendly removable container is provided in pollutant removal unit.
[0089] According to one embodiment of the present invention, a safety system is provided which prevents the plurality of UV lamps from excessive heating and also reduces the amount of foul odour generating gases such as mercaptan created by the UV disinfection.
[0090] The safety system turns ON a first set of UV lamps from among the plurality of UV lamps for a pre-defined time interval and turns OFF the first set of UV lamps and turns ON a second set of UV lamps from among the plurality of UV lamps after the pre-defined time interval, thereby preventing over heating of the first and the second set of UV lamps. The safety system toggles between the first set of UV lamps and the second set of UV lamps until the air purifier system is switched off from a main power line. The safety system is operable to selectively control the plurality of UV lamps upon the air purifier system being operated be-yond a predetermined time duration. In an embodiment, the safety system turns OFF the plurality of UV lamps upon completion or interruption of a disinfection cycle. The pre-defined time interval is based on a size of the indoor environment and a volume of the air inside the indoor environment to be disinfected.
[0091] According to one embodiment of the present invention, the air purifier system disclosed herein can be used in any indoor environment such as, but not limited to, bedrooms, common rooms, halls, office cabins, office common areas, retail shops, hospital rooms, movie theatres, clinics, shopping malls and the like.
[0092] FIG. 1 illustrates an isometric view of an air purifier system 100, ac-cording to one embodiment of the present invention. The air purifier system 100, of FIG. 1, includes a HEPA filtration unit 102, a disinfection unit 104, and a pollutant removal unit 106. In an embodiment, the HEPA filtration unit 102 is configured for extracting air from an indoor environment external to the air purifier system and performing a HEPA filtration. The HEPA filtration unit 102 includes a first plurality of vents 107A-N for inlet of air and at least one HEPA filter bed for filtering the extracted air via HEPA filtration. In an embodiment, the disinfection unit 104 is coupled to the HEPA filtration unit 102. The disinfection unit 104 includes a plurality of UV lamps disposed in a crisscross arrangement inside the disinfection unit 104, for receiving the HEPA filtered air and for performing a 360 degrees UV based dis-infection using the plurality of UV lamps to generate a disinfected air.
[0093] In an embodiment, the pollutant removal unit 106 is coupled to the disinfection unit 104 and is configured to remove harmful gaseous pollutants from the disinfected air and for releasing purified air through an outlet. The pollutant removal unit 106 includes at least one graphene-material based active bed for filtering harmful gaseous pollutants.
[0094] In an embodiment, the air purifier system 100 is controlled by a control panel 108 provided on a front side 110 of the pollutant removal unit 106. The control panel 108 includes a power cord (not shown) that connects the air purifier system 100 to an electrical socket. The air purifier system 100 also includes switch-es including a main power switch 112 and an ON/OFF switch 114 to turn ON/ OFF the plurality of UV lamps. Further, the control panel 108 also includes light emitting diodes (LEDs) 116 and 118 provided for displaying the ON/ OFF status of the air purifier system 100 and of the UV lamps. A counter is provided and configured to count a number of days the HEPA filtration unit 102 is active or operational. The counter begins counting upon the depletion level of the at least one HEPA filter bed reaching below a predetermined threshold level. The predetermined threshold level is indicated by a manufacturer.
[0095] In an embodiment, the air purifier system 100 also includes a safety system communicatively associated with the control panel 108, to prevent the excessive overheating of the UV lamps and to reduce the amount of foul smell created by UV disinfection. The safety system allows all the UV lamps to run for a pre-defined time interval and post pre-defined time interval, a first set of the UV lamps (for example, half of the plurality of UV lamps) are switched off and a second set of UV lamps (for example half of the plurality of UV lamps) are kept on. After a pre-defined time interval, the switched off UV lamps are switched back on and the lamps which were previously on, are turned off for a pre-defined time interval. The safety system toggles between the first set of UV lamps and the second set of UV lamps until the air purifier system is switched off from a main power line, and the safety system is operable to selectively control the plurality of UV lamps upon the air purifier system being operated beyond a predetermined time duration. The pre-defined time interval is based on a size of the indoor environment and a volume of the air inside the indoor environment to be disinfected. In an embodiment, the pre-defined time interval. The switching between the lamps keeps on happening until the main power switch 112 is turned off thereby preventing overheating of the UV lamps.
[0096] The pollutant removal unit 106 also includes a second plurality of vents 120 to release the purified air out of the air purifier system 100. The HEPA filtration unit 102 and the disinfectant unit 104 are coupled together using screws 122. The disinfectant unit 104 and the pollutant removal unit 106 are coupled together using screws 124. The three units are sealed properly so as there is no leakage of air or UV light or smell or any other gas out of the air purifier unit 100 other than purified air from the second plurality of vents 120.
[0097] In an embodiment, the air purifier system 100 optimizes at least one of: a power flux from the plurality of UV lamps, a distance between the plurality of UV lamps, and a time required by the air to stay or pass through the air purifier system 100, to inactivate the pathogens.
[0098] FIG. 2 illustrates an exploded view of the high efficiency particulate air (HEPA) filtration unit 102 of the air purifier system 100 of FIG. 1, according to one embodiment of the present invention. The HEPA filtration unit 102 includes the first plurality of vents 107A-N for inlet of air inside the air purifier system 100, a removable container 202, at least one HEPA filter bed 204, and a support channel 206. The removable container 202 is provided for the placement of the HEPA filter bed 204. The removable container 202 and the HEPA filter bed 204 together is slid-able into the HEPA filtration unit 102 via the support channel 206.
[0099] FIG. 3 illustrates a vertical cross-sectional view of the disinfectant unit 104 of the air purifier system 100 of FIG. 1, according to one embodiment of the present invention. The disinfectant unit 104 includes an outer surface 302 made of a non – UV transmitting material such as for example, polymethyl methacrylate (PMMA), polycarbonate (PC) or a combination thereof and an inner surface 304 made of a reflective sheet. The reflective sheet is made of materials such as for ex-ample, aluminium, stainless steel, aluminized polymer films, silvered polymer films or a combination thereof. The main advantage of using non - UV transmitting material is that it helps in blocking the UV rays so as to ensure that no UV leakage occurs from the air purifier system 100 and also to ensure that any user standing in close proximity of the system 100 is not exposed to UV rays. The role of the above - mentioned reflective sheet is to reflect back the UV rays inside the disinfectant unit 104 and to facilitate attaining 360 degrees disinfection by increasing intensity of the UV rays (e.g., of about of about 1 to100 milli joules (mJ)/square centimeter(cm2)) with-in the disinfectant unit 104 thereby improving an overall disinfection rate.
[0100] The disinfectant unit 104 also includes a plurality of UV lamps 306A-N arranged horizontally in a crisscross pattern to provide high intensity UV expo-sure (of, for example 1 – 100mJ/cm2) that could be sufficient for inactivation of various pathogens. FIG. 3 depicts four UV lamps 306A-N for the purpose of illustration, however in other embodiments more than four UV lamps may be included in the disinfectant unit 104. The disinfectant unit 104 also includes a plurality of electronic ballasts 308A-N disposed behind the inner surface 304 so that they do not hinder the activity of the inner surface 304.
[0101] FIG. 4A depicts a side cross sectional view of the pollutant removal unit 106 of the air purifier system 100 of FIG. 1, according to one embodiment of the present invention. In an embodiment, the pollutant removal unit 106 includes a fan 402, for circulation of purified air and the second plurality of vents 120 for the outlet of purified air. The fan 402 is positioned at the top or at the bottom of the pollutant removal unit 102. The pollutant removal unit 106 is connected to an electrical socket by electrical cord 404. The pollutant removal unit 106 also includes a removable container 406 provided for the placement of one or more graphene materials based active beds 408, that slides into the pollutant removal unit 106. The pollutant removal unit 106 also includes the control panel 108 disposed on the front side of the pollutant removal unit 106 that controls a time duration of air purification. The control panel 108 provides the capability to select a specific time duration with respect to a specific coverage area. FIG. 4B depicts an enlarged view of the control panel 108 of the pollutant removal unit 106 of FIG. 4A, according to one embodiment of the present invention. The air purifier system 100 also includes switches including a main power switch 112 and an ON/OFF switch 114 to turn ON/ OFF the plurality of UV lamps 306A-N. Further, the control panel 108 also includes light emitting diodes (LEDs) 116 and 118 provided for displaying the ON/ OFF status of the air purifier system 100 and of the plurality of UV lamps 306A-N. The LEDs 116 and 118, glow when the plurality of UV lamps 306A-N is ON indicating that the UV disinfection is ongoing.
[0102] In an embodiment, the LEDs 116 and/or 118 is provided for displaying the ON/ OFF status of the air purifier system 100 and of the UV lamps. A counter is provided and configured to count a number of days the HEPA filtration unit 102 is active, and wherein the counter begins counting upon the depletion level of the at least one HEPA filter bed 204 reaching below a predetermined threshold level. In an embodiment, the predetermined threshold level is indicated by a manufacturer
[0103] FIG. 4C depicts an exploded view of the graphene based active bed of FIG. 4A, according to one embodiment of the present invention. The pollutant removal unit 106 includes one or more graphene-material based active beds 410 and 412 for filtering harmful gaseous pollutants. The graphene- material based active beds 410 and 412 are covered from top and bottom by support fabrics 414 and 416. Examples of the graphene-material includes, but is not limited to, graphene oxide, functionalized graphene oxide, (3D) graphene, graphene nanoplatelets, graphene ceramic composites and the like with appropriate density for higher purification efficiency and minimum pressure drop. The graphene- material based active beds 410 and 412 are supported by an outer casing 420 and 422 made from acrylic or metals such as but not limited to, stainless steel or mild steel or aluminum or similar materials. In an embodiment, the graphene- material based active beds 410 and 412 comprise graphene-based materials 418 with a concentration of 0.001 gram/cubic centi-meter (g/cc) – 1.0 g/cc for maximum filtration efficiency and minimum pressure drop.
[0104] FIG. 5 is a flow chart illustrating a method of air purification using the air purifier system 100 of FIG. 1, according to one embodiment of the present invention. At step 502, air is extracted from a first plurality of vents 107A-N of a HEPA filtration unit 102 of the air purifier system 100. At step 504, the air is filtered through at least one HEPA filter bed 204 comprised in the HEPA filtration unit 102 for removing dust particles and particulate matter. At step 506, 360 degrees of disinfection is performed by exposing the air to a UV radiation in a disinfection unit 104 coupled to the HEPA filtration unit 106 for disinfecting the air by inactivating pathogens. The disinfection unit 104 includes a plurality of UV lamps 306A-N dis-posed in a crisscross arrangement and an inner surface 304 made of a UV reflective material for facilitating the 360 degrees of disinfection by reflecting the UV radiation within the disinfection unit 104. At step 508, the disinfected air is passed through at least one graphene based active bed 408 of a pollutant removal unit 106 coupled to the disinfectant unit 104 by extracting the disinfected air through a fan 402 comprised in the pollutant removal unit 106, for removing pollutants from the disinfected air and generating a purified air. At step 510, the purified air is released out of the air purifier system 100 through a second plurality of vents 120 associated with the pollutant removal unit 106.
[0105] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments.
[0106] It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope.
[0107] Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the embodiments herein with modifications. Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the embodiments herein with modifications.

G) ADVANTAGES OF THE INVENTION:
[0108] The embodiments of the present invention provide an air purifier system 100 and method for air purification in an indoor environment, containing pathogens or dust or pollen or toxic gases and other similar harmful gases. This invention is also related to exposing an air column to UV radiation for pathogen inactivation.
[0109] Various embodiments of the present invention provide an air purifier system 100 which can be installed in any indoor environment such as for example homes, shops or offices for purification of air for the prevention of contamination spread through air. The air purifier system 100 of the present invention can be in-stalled in high risk areas such as hospitals or clinics where chances of contamination spread are higher. Also, the air purifier system 100 and method of the present technology employs a UV based air purification to remove harmful gases such as sulphur oxides (SOx), nitrogen oxides (NOx), carbon di oxide, carbon mono oxide, benzene, toluene, ammonia, hexane, formaldehyde, mercaptan, xylene and other similar gases. Further, the present technology provides an efficient technique that uses UV radiation in a range of 100–280 nm wavelength to inactivate the pathogens present in the air. Furthermore, the present technology uses a graphene-material based filtration for removing any ozone or foul-smelling compounds such as thiols, mercaptans created due to the UV light disinfection. Furthermore, the present technology uses a high efficiency particulate air (HEPA) filter bed 204 for particulate material removal up to 0.3 microns.
[0110] Additionally, the present invention provides a user-friendly removable container in the HEPA filtration unit 102 for easy replacement of the HEPA filter bed 204 and also a removable container 406 in the pollutant removal unit 106 for easy replacement of at least one graphene material based active bed 408 facilitating easy maintenance. Moreover, the present invention includes a safety system that al-lows half of the UV lamps to turn on alternatively with rest of the UV lamps for a desired or preset time to prevent overheating and maintain safety.
[0111] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
[0112] Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the embodiments herein with modifications.
[0113] It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications. However, all such modifications are deemed to be within the scope of the claims.
,CLAIMS:We Claim:
1. An air purifier system (100) comprising:
at least one high efficiency particulate air filtration unit (HEPA filtration unit) (102) comprising at least one HEPA filter bed (204) for extracting air from ex-ternal atmosphere and performing a HEPA filtration;
at least one disinfection unit (104) coupled to said HEPA filtration unit (102) and comprising a plurality of ultraviolet (UV) lamps (306A-N) disposed in a criss-cross arrangement, for receiving the HEPA filtered air and for performing a 360 de-grees UV based disinfection to generate a disinfected air; and
at least one pollutant removal unit (106) coupled to said disinfection unit (104) and configured to remove harmful gaseous pollutants from the disinfected air and for releasing purified air to an indoor environment, and wherein said pollutant removal unit (106) comprises at least one graphene-material based active bed for filtering harmful gaseous pollutants.
2. The air purifier system (100) as claimed in claim 1, wherein said HEPA filtration unit (102) comprises a first plurality of vents (107A-N) for inlet of air and said pol-lutant removal unit (106) comprises a second plurality of vents (120) for outlet of purified air.
3. The air purifier system (100) as claimed in claim 1, wherein said pollutant removal unit (106) comprises a fan (402) for circulating purified air.
4. The air purifier system (100) as claimed in claim 1, comprising one or more switch-es, a main power switch (112) and a safety switch (114) to turn ON/ OFF the plurali-ty of UV lamps (306 A-N).
5. The air purifier system (100) as claimed in claim 1, wherein the disinfectant unit (104) comprises an inner surface (304) made of a UV reflective material and an out-er surface (302) made of a non-UV transmitting material, wherein said UV reflec-tive material of said inner surface (304) and said non-UV material of said outer sur-face (302) restricts UV rays from said plurality of UV lamps (306 A-N) within the disinfectant unit (104) by reflecting the UV rays and facilitates 360 degrees of disin-fection within the disinfectant unit (104).
6. The air purifier system (100) as claimed in claim 1, comprising a control panel (108) to control a time duration for UV radiation-based disinfection.
7. The air purifier system (100) as claimed in claim 6, wherein said control panel (108) comprises at least one light emitting diode (LED) (116 or 118) for displaying the ON/ OFF status of the air purifier system 100 and of the UV lamps, wherein a coun-ter is provided and configured to count a number of days the HEPA filtration unit 102 is active or operational thereby indicating a depletion level of the at least one HEPA filter bed (204), and wherein said counter begins counting upon said deple-tion level of the at least one HEPA filter bed (204) reaching below a predetermined threshold level, and wherein said predetermined threshold level is indicated by a manufacturer.
8. A method of air purification comprising:
extracting (502) air from a first plurality of vents of a HEPA filtration unit (102) of an air purifier system (100) ;
filtering (504) said air through at least one HEPA filter bed (204) comprised in said HEPA filtration unit (102) for removing dust particles and particulate matter;
performing (506) a 360 degrees of disinfection by exposing said air to an ul-traviolet (UV) radiation in a disinfection unit (104) coupled to said HEPA filtration unit (102) for disinfecting said air by inactivating pathogens, wherein said disinfec-tion unit (104) comprises a plurality of UV lamps (306A-N) disposed in a crisscross arrangement and an inner surface (304) made of a UV reflective material for facili-tating said 360 degrees of disinfection by reflecting said UV radiation within said disinfection unit (104);
passing (508) said disinfected air through at least one graphene based active bed (410 and 412) of a pollutant removal unit (106) coupled to said disinfectant unit (104) by extracting said disinfected air through a fan 402 comprised in said pollu-tant removal unit 106, for removing pollutants from said disinfected air and generat-ing a purified air; and
releasing (510) said purified air out of said air purifier system (100) through a second plurality of vents (120) associated with said pollutant removal unit (106).
9. The method as claimed in claim 8, wherein performing the 360-degree disinfection comprises optimizing at least one of: a power flux from the plurality of UV lamps (306A-N), a distance between the plurality of UV lamps (306A-N), and a time re-quired by the air to stay or pass through the air purifier system (100), to inactivate the pathogens.
10. The method as claimed in claim 8, comprising preventing overheating of the plurali-ty of UV lamps (306A-N) by automatically cutting off the power of the plurality of UV lamps (306A-N) after a lapse of a pre-defined time duration of operation of the plurality of UV lamps (306A-N), wherein the pre-defined time duration is based on a size of the indoor environment to be disinfected.
11. The method as claimed in claim 8, comprising preventing overheating of the plurali-ty of UV lamps (306A-N) by turning ON, using a safety system, a first set of UV lamps from among the plurality of UV lamps (306A-N) for a pre-defined time inter-val and turning OFF the first set of UV lamps and turning ON a second set of UV lamps from among the plurality of UV lamps (306A-N) after the pre-defined time interval.
12. The method as claimed in claim 11, wherein said safety system toggles between said first set of UV lamps and said second set of UV lamps until the air purifier system (100) is switched off from a main power line, wherein the safety system is operable to selectively control the plurality of UV lamps (306A-N) upon the air purifier sys-tem (100) being operated beyond a predetermined time duration.
13. The method as claimed in claim 8, comprising turning OFF the plurality of UV lamps (306A-N) upon completion or interruption of a disinfection cycle.
14. The method as claimed in claim 11, wherein said pre-defined time interval is set based on a size of said indoor environment and a volume of the air inside the indoor environment to be disinfected.