FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10; Rule 13)
TITLE
“AIR FILTERING SYSTEM IN EVAPORATIVE AIR COOLER”
APPLICANT
Symphony Limited,
Symphony House, FP 12, TP 50,
Off. S.G. Highway, Bodakdev,
Ahmedabad - 380 054,
Gujarat, India.
The following specification describes the invention
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AIR FILTERING SYSTEM IN EVAPORATIVE AIR COOLER
FIELD OF INVENTION:
The present invention generally relates to an evaporative air cooler, characterized in using several air purification methods including but not limited to removal of dust, mites, insects, smell (odour), volatile organic compounds, particulate matter, and microbial matter, wherein said filters are arranged between an air inlet and an air outlet of the evaporative air cooler in order to purify the passing air and simultaneously maintaining the effective blow of cool fresh air to the human comfort zone (enclosed room or the desired target area, nearby said evaporative cooler).
Background of the invention:
The air pollution has become quite severe globally and air in our surrounding generally contains many hazardous substances and pollutants, such as volatile organic compounds, microbial matter, formaldehyde, dust, mites etc.When air containing such hazardous substances and pollutant dust, harmful to the human body, is ingested without any filtration, it will have various adverse effects on the human body which is mainly affecting the respiratory system and cardiovascular system damage, including respiratory irritation, coughing, breathing difficulties, reduced lung function, aggravate asthma, cause chronic bronchitis, arrhythmia, nonfatal heart attack, lung and heart disease, also leading to premature death.
In the prior arts, air purifiers and evaporative air coolers are two different products. Air purifiers are designed for use in a closed room and fail to provide constant source of fresh air. Indoor air quality hence suffers due to stale air in the space. Further, none of the conventional purification system use air washing technique to the advantage, particularly while the received air is simultaneously cooled and made moist.
Evaporative air coolers are good to provide fresh cool air, wherein such air coolers function on the principle of passing the incoming air through a water vapour cooled chamber, maintained by continuous flow of water thereof. Such air coolers of prior arts
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which involve water evaporation for air cooling are not designed to purify the air. Further an evaporative media and the water maintained there in become active carrier of microorganisms.
Air coolers are more effective in dry, hot and tropical locations. Present day air coolers typically comprise of a body, a water tank, fibre pads of different possible materials, air moving device (axial or centrifugal or cross flow fans) and water circulation system. A motorized air-moving device mounted within the body of the air cooler — with fibre pads mounted on at least one of the sides of the air cooler blows the cool air from the air outlet, usually at front or top of the air cooler. The loosely woven fibres of the fibre pads are preferably made of wood shavings or cellulose. In case when fibre pads are made of wood shavings, wool is filled in the cotton net of the fibre pad and in the case when fibre pads are made of cellulose, the fibre pad consist of paper and special adhesive with multiple layer of corrugated paper arranged in honeycomb manner. The fibres of the pads are kept wetted using a water distribution system.
Conventionally, air inlet grills of the evaporative air coolers are kept open, in order to allow air to be drawn with minimum resistance from the air inlet of the air cooler. Such an air inlet has to be kept open during air blow, at the best one can put a plastic mesh or metal mesh or cotton mesh to remove insects and remove very coarse dust particles. It is also not feasible to place any air filter at the air outlet, because the velocities are quite high and resistance will be high too.
As a result, various kinds of pollutants can easily enter the air cooler from such inlet grills. Ingress of dust and other particles and microbial matter into the air cooler also lead to unpleasant smell issues over a period of time and the delivered air from the air outlets are dusty and pollutant. There are variety of pollutants in ambient air like particulate matter, volatile organic compounds, formaldehyde, harmful gases, dust, mites, pollen, microbial matter etc. which are harmful to human beings. Air coolers of prior art have no mechanism to purify air by removing all these pollutants.
Further, the insides of the air cooler (tank, pad) are often wet for some time after the air cooler is switched off. This can lead to breeding of mosquitoes, insect and other microbial matter. These microbial matters can enter water and can eventually pass in
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the air stream. Air coolers of prior art have no devices or processes to control the growth or filtration of microbial matter before letting them pass to the air stream.
Further in the prior art, the air coolers which also filter the air, contain what can be described as “Air Pre-Filter”. These air pre-filters can remove coarse dust particles in air, but are ineffective against most other pollutants. The filter system of the evaporative air cooler according to the prior art generally comprise a pad filter, and air moving device (axial or centrifugal or cross flow fans) which is not effective for cleaning the air.
The highest challenge in using conventional air purifier processes in air coolers of prior art arise due to high static pressure drop of these air purifying process, which result in drastic reduction of air delivery and hence most conventional air purification processes are not effective to be used in conjunction with air coolers.
The present invention has resolved those challenges and devised air purification processes, air washing process and water purification processes which can together effectively purify the air to the desired air quality and at the same time maintain cooled air blow pressure, without any significant reduction in air delivery volume of a given evaporative air cooler.
OBJECTS OF THE INVENTION:
Prime object of the present invention is to propose an evaporative air cooler with air purification means for obtaining effective volume of purified cool air in a target human comfort zone or an enclosed such area.
Another prime object of the present invention to propose an evaporative air coolers with a series of air and water purification means and processes involved therein, mainly towards purifying and washing the air and remove variety of pollutants such as dust, particulate matter, microbial matter, mites, pollen, volatile organic compounds, formaldehyde, harmful gases, etc. and thereby provide a high quality indoor air to the user.
Another object of the invention is to propose preparing and installation of an assembly/combination of antimicrobial agent(s) for air filters and other pollutant
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removal filter units within an evaporative air cooler body, wherein said assembly/combination of said antimicrobial agent(s) for air filters and other pollutant removal filter units, during the normal functioning of the evaporative air cooler, simultaneously filters or removes almost all pollutants from the outgoing cooled air very effectively without significantly reducing the air delivery volume.
Another object of the present invention is to propose a filtering system for an evaporative air cooler, wherein said assembly of filtering system comprises several optionally selected filter units, namely particulate attenuators filter, active carbon filter, Anti Bacterial filter, filter module containing Titanium dioxide, Ionizer, Water pre-filter sponge, ultraviolet C ray filter, Air washer, Magnetic water filter, Silver Ion filter, etc.
Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein various filter units of said filtering system are optionally selected and are assembled within the body of the evaporative air cooler at suitably available spaces depending upon the size and shape of said evaporative air cooler.
Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein shape, size and dimension of various individual filter units of said filtering system are optionally selected depending upon the size and shape of the evaporative air cooler, its water pumping capacity, its air blowing fan assembly and its capacity to blow cool filtered air to a pre-determined space, such as an enclosed human comfort zone or an open such target area.
Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein particulate attenuator filter mainly comprises of very fine glass fiber threads; active carbon filter mainly comprises granules of activated carbon base material of Terylene; Anti Bacterial filter mainly comprises granules of an antibacterial materials, chemically treated with Copper Nitrate and activated Carbon Fabric; and the Titanium dioxide filter comprises granules of Titanium dioxide, wherein Titanium dioxide is chemically treated by Activated Carbon Fabric.
Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein Ionizer contains an electrically charged wire and it sends charged molecules into the air.
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Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein Water pre-filter (Sponges) comprises cellulose wood fibers or foamed plastic polymers; Ultraviolet C ray filter comprises an electromagnetic radiation with a wavelength from 100 to 280 nm.
Another object of the present invention is to propose an evaporative air cooler with the assembly of filtering system; wherein Air washer comprises loosely woven fibres or hay wool; and the Magnetic water filter comprises an alloy of neodymium, iron and boron.
SUMMARY OF THE INVENTION:
The present invention generally relates to an evaporative air cooler, characterized in using several air purification methods including but not limited to removal of dust, mites, insects, smell (odour), volatile organic compounds, particulate matter, and microbial matter, wherein said filters are arranged between an air inlet and an air outlet of the evaporative air cooler in order to purify the passing air and simultaneously maintaining the effective blow of cool fresh air to the human comfort zone (enclosed room or the desired target area, nearby said evaporative cooler).
The filters arranged according to the present invention have a function of collecting fine dust and also removing odour, volatile organic compounds, formaldehyde, and, also filter out and deactivate (and inhibit growth of) most microorganisms in air, including bacteria and fungi, even when it is used for a long period of time. Since air gets cooled by evaporation of water, the present invention also incorporates water filtration using certain techniques which are best suited for the purpose. The challenge in present invention is to devise all filtration processes such that they do not significantly affect the air delivery volume which is one of the most critical specifications of any evaporative air cooler.
The present disclosure is generally about preparing and installation of an assembly/combination of antimicrobial agent(s) for air filters and other pollutant removal filter units within an evaporative air cooler body, wherein said assembly/combination of said antimicrobial agent(s) for air filters and other pollutant removal filter units, during the normal functioning of the evaporative air cooler, simultaneously filters or removes almost all pollutants from the outgoing cooled air
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very effectively without significantly reducing the air delivery volume. As used herein, the term “antimicrobial” is intended to cover both antibacterial and antifungal.
The main object of the invention is to provide air purification means for an evaporative air cooler whereby various optionally selected filtration processes are proposed to vastly improve the air quality of the cooled air outgoing from the body of the evaporative air cooler.
This is achieved by providing a combination of special and optional air filter units, namely particulate attenuators filter, active carbon filter, Anti Bacterial filter, filter module containing Titanium dioxide, Ionizer, Water pre-filter sponge, ultraviolet C ray filter, Air washer, Magnetic water filter, Silver Ion filter, etc.
Accordingly, the invention relates to an improved evaporative air cooler having a housing (body) including top panel, side panels, back panel, front panel, bottom panel, a cooler pad assembly adjacent to at least one of the side panels, and, a fan (axial or centrifugal or cross-flow) which in use – draws air through said cooler pad assembly, and a motor to operate said fan and said pump. The improvements include assembly/combination of filtering system comprising plurality of filter units, namely particulate attenuators filter, active carbon filter, Anti Bacterial filter, filter module containing Titanium dioxide, Ionizer, Water pre-filter sponge, ultraviolet C ray filter, Air washer, Magnetic water filter, Silver Ion filter, etc., which are together having properties of completely cleaning the air and said optionally selected plurality of filter units are located in the air path within the body of an evaporative air cooler. As the air cooling is performed within the body of the evaporative air cooler in presence of ample volume of water in the water tank of said cooler, it is also necessary to purify the water content of the said evaporative air cooler while said air cooler is in funcition of delivering cool fresh air, mainly in terms of removing/deactivating microbes, dust, husk, odour, unwanted salts and other such impurities. The water is additionally cleaned using an optional combination of pre-filter, magnetic removal and ultraviolet C-rays.
Preferably, the filtering system is provided with different types of filter units, which can be arranged in different shapes and different colours/textures/appearances.
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Generally, microorganisms harmful to the human body have a size of a few microns, and such microorganisms are removed through particulate attenuator filters and further deactivated using other optional filters like Activated Carbon, Anti-bacterial cold catalyst, Silver Ions, Titanium dioxide filter, UV light and ionizer in the filter system. Air gets continuously washed through water using a specially designed evaporative cooling media. Water in the system is then cleaned through a series of optional filtration processes like ultraviolet C rays, sponge filter, and, magnetic filtration.
These filters use a kind of filtration media and such media can be made of, for example, polypropylene fibres, which is a specially charged fibre. Such filters are mounted in an evaporative air cooler to filter even fine hazardous substances and pollutant dust. Also, these filters have a strong adsorption capability to completely remove hazardous substances such as dust, mites, formaldehyde, volatile organic compounds, particulate matter, harmful gases, odour, viruses and fungi, which are contained in air and are harmful to the human body, and pollutant particulate matter which is very harmful to the human body, at a high removal rate.
The air cooler of the present invention is designed to be used for the convenient cooling of any room or similarly enclosed space or even open space including but not restricted to the rooms of a house, office, shop, warehouse, manufacturing location, process industry, assembly hall, restaurant etc. while purifying the air before delivering such cool air to the space.
Installation or mounting of optionally selected filter units of said filtering system within the body of the evaporative air cooler is preferably through slide-able/screw-able means or by other type state-of-the-art arrangements for engaging the said filter units within the body of said air cooler.
The filtering system arrangement in an evaporative air cooler comprises of several filter units like Activated Carbon filter, Anti-Bacterial filter, filter module containing Titanium dioxide, filter module containing Silver Ion, particulate attenuation filters and ionizer, preferably being rectangular or in any other shape and size and colour having an optional peripheral frame, and a further set of guides complementary to said filter. Further provided with air washing arrangement, where 100% of the incoming air passes through the said air washing process and gets cleaned of particulate matter and various other air pollutants, particularly soluble air pollutants. Said filtering system
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of the evaporative air cooler is so provisioned that the water itself is kept clean by using an optional combination of ultraviolet C rays, magnetic filtration and pre-filter.
The arrangement of the filtering system within the body of the evaporative air cooler is made in such a manner that the individual filter units therein are kept upstream of the air washing pads, which are wet filter pads. A filters arrangement within the body of the evaporative air cooler is so chosen that said main embodiment of the filtering system lies adjacent to said air washing pad but its filter material does not contact to air washing pads.
One embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises of filter pad comprising of filtering material, selected from a dry porous membrane of inert material.
One embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of activated carbon base material of Terylene, downstream of said dry porous membrane.
One embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of Antibacterial material(s), which is chemically treated by Copper Nitrate with Activated Carbon Fabric downstream of said dry porous membrane.
One embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of Titanium dioxide, which is chemically treated by Activated Carbon Fabric with Titanium dioxide downstream of said dry porous membrane.
One embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising a set of particulate attenuator filter, which is content fiber glass downstream of said dry porous membrane.
DETAILED DESCRIPTION OF THE INVENTION:
The invention will now be described with reference to the accompanying drawings wherein the same numerals are used to denote the same parts. However, it is made
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clear that the description and the drawings only illustrate the invention and in no way limit the same.
An embodiment is described in detail hereinbelow with reference to the drawings.
FIG. 1 is a perspective view of an evaporative air cooler in its assembled form,
FIG. 2 is an exploded view of the cooler illustrating the main component parts thereof.
In the most preferred embodiment of the evaporative air cooer with air filter means, as depicted in the drawings, an evaporative air cooler (10) comprises an evaporative cooler body (11) which itself comprises front panel (12), a back panel (16) and base tank (17). Adjacent the back panel (16), there is located a pad assembly (13) comprising an evaporative pad (14) containing a fibrous absorption material, which is arranged to provide a large surface area for evaporation of the water, which runs downwardly there through and Particulate attenuator filter (22), carbon filter (23), Anti Bacterial filter (24), filter module containing Titanium dioxide granules (25), Ionizer (29), water pre-filter sponge (30), ultraviolet C ray filter (31), air washer (32), Magnetic water filter (33), Silver Ion filter, etc. which are arranged to provide a clean air. The fan (18) (axial or centrifugal or cross flow fans), which includes a fan housing (19), and motor (20), and the pump (21) for pumping water through the unit, are assembled in the cooler body in known manner as shown in FIG. 2. It will be realised that not all parts of the unit have been shown. Various type of pump and pumping arrangements are available in the prior art, and, this invention is not restrictive in use of such pumps.
In accordance with this invention, a provision is made for a filtering system (26) preferably constructed from integrated assembly or simple combination of plurality of filter units, capable of performing specific air or water filtering/treating action and as a synergistic effort of said plurality of filter units, said assembly/combination of the filtering system (26) purifies the air within the body of the evaporative air cooler (11), particularly when said evaporative cooler (10) is in function for cooling and delivering cool air to the human comfort zone. Said individual filter units are optionally selected from:-
Particulate attenuator or removal filter (22), made out of very fine glass fiber threads;
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Active Carbon filter (23), comprises granules of activated carbon base material of Terylene;
Anti Bacterial filter (24), comprises granules of antibacterial materials and it is chemically treated by Copper Nitrate with Activated Carbon Fabric;
Titanium dioxide filter (25), comprises granules of Titanium dioxide, wherein Titanium dioxide is chemically treated by Activated Carbon Fabric;
Ionizer (29), contains an electrically charged wire and it sends charged molecules into the air;
Water pre-filter (Sponges) (30) comprises cellulose wood fibers or foamed plastic polymers;
Ultraviolet C filter (31) comprises an electromagnetic radiation with a wavelength from 100 to 280 nm;
Air washer (32) comprises loosely woven fibres or hay wool; and
Magnetic water filter (33) comprises an alloy of neodymium, iron and boron.
The location for various elements of the complete Filtering system (26) can be suitably selected in optionally available different possible locations within the body (11) of the air cooler, preferably near the back panel (16), so that the same can be assembled between the air inlet (27) and air outlet path (28).
Therefore depending of the dimension of the body 11 of the evaporative air cooler 10 and the availability of inner space within the said body 11, all the optionally chosen filtering units of said filtering system 26 are fitted to any of the panels of the housing or any of the inner structural parts of the air cooler 10. The shape, size and colour of individual filter units of said filtering system 26, viz. particulate attenuator filter 22, active carbon filter 23, Anti Bacterial filter 24, Titanium dioxide filter 25, ionizer 29, water pre-filter sponge(s) 30, ultraviolet C filter 31, air washer filter 32, magnetic water filter 33 and Silver Ion filter etc. are optionally selected depending upon the size and shape of the evaporative air cooler 10, its water pumping capacity, its air blowing fan assembly and its capacity to blow cool filtered air to a pre-determined space, such as an enclosed human comfort zone or an open such target area.
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In the preferred embodiment as depicted in figures 1 and 2, the filtering system 26 comprises an optional shallow cassette 27 for fixing a particulate attenuator/removal filter 22, carbon filter 23, Anti Bacterial 24, Titanium dioxide 25, ionizer 29, water pre-filter 30, ultraviolet C filter 31, air washer filter 32, magnetic water filter 33 and Silver Ion filter etc. May also be fixed with different possible manner too thereby it can be fitted with any type of fixing method like screw fitted, snap fitted etc.The optional shallow cassette 27 made up of any different possible materials.
A brief consideration of the above embodiment will indicate that the invention is simple. The invention eliminates hazardous substances and pollutant dust of air, which pass through the evaporative air cooler.
In addition to the above mentioned embodiments, it is to be understood that various modifications and alterations with regard to the types of the materials used, their method of joining together, and the attachments, and, the shape of the air cooler, the structure of the air cooler, the shapes / dimensions / orientations of the components as describes, the absence of certain optional components as described, and/or function may be made to the disclosed embodiments by one skilled in the art without departing from the invention as defined by the claims. Accordingly, the above disclosure is not to be considered as limiting and the appended claims are to be interpreted as encompassing the entire spirit and scope of the invention.
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WE CLAIM:
1. An evaporative air cooler (10) comprising of the filtering system (26), wherein said cooler (10) comprises a series of air and water purification means and processes involved therein, mainly towards purifying and washing the air and remove variety of pollutants such as dust, particulate matter, microbial matter, mites, pollen, volatile organic compounds, formaldehyde, harmful gases, etc. and thereby provide a high quality indoor air to the user.
2. An evaporative air cooler (10) comprising of the filtering system (26), as claimed in claim 1, wherein said cooler (10) comprises a filtering system (26), which consists of an assembly or combination of plurality of optionally selected filter units, namely particulate attenuators filter (22), active carbon filter (23), Anti Bacterial filter (24), filter module containing Titanium dioxide (25), Ionizer (29), Water pre-filter sponge (30), ultraviolet C ray filter (31), Air washer (32), Magnetic water filter (33), Silver Ion filter etc.; wherein said evaporative air cooler is characterized in simultaneous cooling and purifying the air within its body (11) between the air inlet (27) and air outlet path (28), while said cooler (10) is in function and delivering the cooled and purified air to an enclosed or open human comfort zone.
3. The filtering system (26), as claimed in claim 1, wherein individual filter units of said filtering system (26) are optionally selected from:-
Particulate attenuator or removal filter (22), made out of very fine glass fiber threads;
Active Carbon filter (23), comprises granules of activated carbon base material of Terylene;
Anti Bacterial filter (24), comprises granules of antibacterial materials and it is chemically treated by Copper Nitrate with Activated Carbon Fabric;
Titanium dioxide filter (25), comprises granules of Titanium dioxide, wherein Titanium dioxide is chemically treated by Activated Carbon Fabric;
Ionizer (29), contains an electrically charged wire and it sends charged molecules into the air;
Water pre-filter (Sponges) (30) comprises cellulose wood fibers or foamed plastic polymers;
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Ultraviolet C filter (31) comprises an electromagnetic radiation with a wavelength from 100 to 280 nm;
Air washer (32) comprises loosely woven fibres or hay wool;
Magnetic water filter (33) comprises an alloy of neodymium, iron and boron; and
Silver ion filter.
4. An evaporative air cooler (10) comprising of the filtering system (26), as claimed in claim 1, wherein the location(s) for the optionally selected plurality of filter units in the assembly or combination of the said Filtering system (26) are suitably selected from optionally available different possible locations within the evaporative air cooler body (11), preferably near the back panel (16), between the air inlet (27) and air outlet path (28).
5. An evaporative air cooler (10) comprising of the filtering system (26), as claimed in claim 1, wherein depending of the dimension of the body (11) of the evaporative air cooler (10) and the availability of inner space within the said body (11), all the optionally chosen filtering units of said filtering system (26) are fitted to any of the panels of the housing or any of the inner structural parts of the air cooler (10), depending upon the size and shape of said evaporative air cooler (10), its water pumping capacity, its air blowing fan assembly and its capacity to blow cool filtered air to the pre-determined enclosed or open human comfort zone.
6. The filtering system (26), as claimed in claim 1, wherein one preferred embodiment of a filters pad arrangement comprising of several filters like Activated Carbon, Anti-Bacterial, Titanium dioxide, Silver Ion, particulate attenuation filters and ionizer being rectangular or in any other shape and size and colour having an optional peripheral frame, and a further set of guides complementary to said filter
7. The filtering system (26), as claimed in claim 1, wherein said filtering system is characterized in cleaning of water present in the evaporative air cooler body (11) by using the optional combination of ultraviolet C rays, magnetic filtration and pre-filter sponges.
8. The filtering system (26), as claimed in claim 1, wherein in the filter units of the most preferred embodiment of the filtering system (26) are kept upstream of the air washing pads, which are wet pads; and wherein said filter units preferably
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lie adjacent to said air washing pads (32) but its filter materials do not contact to said air washing pads (32).
9. The filtering system (26), as claimed in claim 1, wherein one embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system (26) optionally comprises of filter pad(s) comprising of filtering material, selected from a dry porous membrane of inert material.
10.The filtering system (26), as claimed in claim 1, wherein one embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of activated carbon base material of Terylene, downstream of said dry porous membrane.
11.The filtering system (26), as claimed in claim 1, wherein one embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of Antibacterial material(s), which is chemically treated by Copper Nitrate with Activated Carbon Fabric downstream of said dry porous membrane.
12.The filtering system (26), as claimed in claim 1, wherein one embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising granules of Titanium dioxide, which is chemically treated by Activated Carbon Fabric with Titanium dioxide downstream of said dry porous membrane.
13.The filtering system (26), as claimed in claim 1, wherein one embodiment of the optionally chosen filter unit of said assembly/combination of the filtering system optionally comprises at least one filter pad, comprising a set of particulate attenuator filter, which is content fiber glass downstream of said dry porous membrane.
14.A method of cooling and cleaning air within an evaporative air cooler (10), as claimed in claims 1 to 13, wherein said method comprises impelling a blow of air through at least one wet-able filter pad within a housing while passing water through said at least one filter pad to wash and cool the air, and pre-filtering the air through a said further filter pad which is preferably positioned upstream of said wet-able filter pad(s) so as to remove and digest pollutants from the cooled and filtered air, moving out from the said evaporative air cooler