Title of Invention	DEVICE FOR PHOTOCATALYTIC TREATMENT OF FLUIDS
Abstract	A reactor unit tor photocalalytic treatment of fluids such as air. includes a catalyse: device (4) comprising a catalytic material support having a generally tubular shape defining a fluid flow channel extending around and along a fluid flow path and a photocatalytic material coated on at least a portion of an internal surface of the support, and a radiation source (30) received in a central portion of the eatalyser device. The catalytic material support comprises a wall portion and a plurality of tapered protrusions (8) extending from an internal surface of the wall portion to a tip proximate to the radiation source, the tapered protrusions being arranged around the radiation source and alone the fluid flow channel.

Title of Invention

DEVICE FOR PHOTOCATALYTIC TREATMENT OF FLUIDS

Abstract

A reactor unit tor photocalalytic treatment of fluids such as air. includes a catalyse: device (4) comprising a catalytic material support having a generally tubular shape defining a fluid flow channel extending around and along a fluid flow path and a photocatalytic material coated on at least a portion of an internal surface of the support, and a radiation source (30) received in a central portion of the eatalyser device. The catalytic material support comprises a wall portion and a plurality of tapered protrusions (8) extending from an internal surface of the wall portion to a tip proximate to the radiation source, the tapered protrusions being arranged around the radiation source and alone the fluid flow channel.

Full Text	Device for photocatalytic treatment of fluids The present invention relates to the field of devices for photocatalytic treatment of fluids, for instance for cleaning, deodorizing and sterilizing gases such as air. Nunnerous air purification systems have been described, or are commercially available, which aim to remove various pollutants, such as dust, micro-particles, noxious gases, allergens, and pathogenic micro-organisms from the air. In the known systems, dust and other micro-particles are generally removed from the air by the use of filters. It is known to remove certain volatile and reactive molecules by the use of catalytic processes. The use of ultraviolet light radiation to inactivate certain micro-organisms is also described. It is known to combine the use of ultraviolet light and photocatalytic processes to accelerate the degradation of noxious particles and the destruction of micro-organisms. The use of photocatalysts in devices for deodorising or purifying air is described in a number of patent applications, for example, US 5,670,126, US 6,558,639, US 2002/094298, US 6,358,374, US 2004/007453, JP 11226357, WO 02/085989, and FR 2821558. The most common photocatalytic compound used in the known systems is titanium dioxide because of its excellent photocatalytic activity when irradiated with ultraviolet radiation, and its harmlessness to the human organism. The photocatalyst is generally combined with a binder to form a photocatytic coating material. A photocatalytic material which is convenient to use, adheres well to a number of surface and may be applied to articles which do not support high temperatures is described in WO 2006/010993, hereby incorporated herein by reference. The photocatalytic material described in WO 2006/010993 comprises an inorganic binder including ultraviolet light permeable polymeric molecules, particularly acrylic molecules, a polar diluent, and particles of an inorganic semi- conductor, such as cadmium sulphide, zinc sulphide or titanium dioxide. In known systems the photocatalytic material is generally coated on a filter element or other surfaces of the air purifying system irradiated by an ultraviolet light source, typically an ultraviolet lamp. For example EP 0978690 and WO 96/37281 describe systems in which air is passed through an air-permeable sheet supporting a photocatalytic material and placed in the vicinity of an ultraviolet light source. Such systems generally provide only limited air cleaning properties with respect to removing certain airborne pollutants, allergens and pathogens. A system with improved air cleaning properties is described by WO 2007/060520, in which a photocatalytic material is coated on an inside surface of a tubular air conduit containing a UV lamp. A number of spaced apart blades are located on the inside surface of the air conduit in order to increase the surface area of photocatalytic material in the air conduit and to create turbulent flow of the air through the conduit. EP 0470518 describes a system designed for the decomposition of organic substances in which a liquid is passed through a stainless steel reaction vessel containing an ultraviolet immersion lamp. According to EP 0470518 baffles are located on the inner surface of the stainless steel tube to cause turbulence in the flow of the liquid on the reaction vessel inner surface. The known systems do however present a number of drawbacks. For instance the known systems are generally relatively complex and costly to manufacture and/or maintain. Moreover, the known systems either do not effectively treat all the air passing through the device, and/or cause excessive resistance on the air passing through with the consequence of increased noise and the need to employ more powerful fans for a given rate of airflow. There is also an ongoing need for air purification systems which reliably and effectively remove, destroy or inactivate airborne pollutants, allergens and pathogens. It is an object of this invention to provide a device for use in the photocatalytic treatment of fluids which provides reliable and effective treatment of said fluids and which is economic to manufacture. It would be advantageous to provide a reactor unit which provides reliable and effective cleaning, deodorizing and sterilizing of air and which is economic to manufacture. It would be advantageous to provide an apparatus for the photocatalytic treatment of fluids that has a low pressure loss for a given rate of treated fluid flow. It would be advantageous to provide an apparatus for the photocatalytic treatment of fluids that has low noise emission. It would be advantageous to provide an apparatus for the photocatalytic treatment of fluids that is easy to use and versatile. It would be advantageous to provide an apparatus for the photocatalytic treatment of fluids that is economic to manufacture, maintain and use. It would be advantageous to provide an apparatus that can conveniently and effectively be used in the photocatalytic treatment of large volumes of fluids. Objects of the present invention are achieved by a reactor unit according to claim 1. Disclosed herein is a reactor unit for photocatalytic treatment of fluids including a catalyser device comprising a catalytic material support having a generally tubular shape defining a fluid flow channel extending around and along a fluid flow path and a photocatalytic material coated on at least a portion of an internal surface of the support, and a radiation source received in a central portion of the catalyser device. The catalytic material support comprises a wall portion and a plurality of tapered protrusions extending from an internal surface of the wall portion to a tip proximate to the radiation source, the tapered protrusions being arranged around the radiation source and along the fluid flow channel. The term "proximate" as used in the present application is meant within a range of 0 (i.e. touching) to a distance of less than 50% the distance separating the surface of the radiation source and the internal surface of the catalytic device wall portion. The tips of the tapered protrusions may be located at a position within a range of 0 (i.e. touching the surface of the radiation source) to a distance of less than 50%, preferably less than 30%, the distance separating the surface of the radiation source and the internal surface of the catalytic device wall portion. For instance, the extremity of the tips of one or more tapered protrusions may be located at a distance within a range of 0 to 20mm from an external surface of the radiation source, preferably within a range of 0 to 10mm, more preferably within a range of 2 to 5 mm. Advantageously the provision of a tubular catalytic material support with a plurality of tapered protrusions extending from a wall portion of the catalytic material support to a tip proximate to the radiation source not only provides a greatly increased surface area of photocatalytic material inside the reactor unit, but also increases the proportion of the coated internal surface of the catalyser device that is exposed to direct ultraviolet light from the radiation source. The plurality of tapered protrusions arranged around the inner periphery of the generally tubular support and along its length in the fluid general flow direction also provide a plurality of meandering paths for the fluid flow, thus increasing the amount of fluid which is brought into contact with the photocatalytic material. Further the arrangement of a plurality of tapered protrusions inside the reactor unit extending to a tip proximate to the radiation source creates a certain amount of turbulence to further increase the contact of air flowing through the reactor unit with photocatalytic material, whilst maintaining a low pressure loss (low resistance) on air flowing through system. Preferably the tapered protrusions extend substantially perpendicularly from the internal surface of the catalytic material support wall portion towards the radiation source. Advantageously having tapered protrusions around the internal surface of the reactor inside the reactor which extend substantially perpendicularly towards a central axis of the radiation source enables the surface area of the photocatalytic material on the catalytic material support that is exposed to direct ultraviolet radiation from the radiation source to be maximised. The plurality of tapered protrusions may preferably be arranged in successive rows around the internal surface of the catalytic material support, each offset at a certain angle with respect to the previous row. Such a stepped (angularly offset) arrangement of the tapered protrusions advantageously provides effective mixing of the air flowing through the reactor unit. Advantageously the tapered protrusions have an average height to largest base diameter ratio of 6:1 to 1:1, preferably 4:1 to 2:1. In this way the surface area of the photocatalytic material support and the distance between the radiation source and the photocatalytic material may be optimised for effective and reliable treatment. The base portion of the tapered protrusions may have any suitable cross-section shape, for instance circular, oval, hexagonal, octagonal, rhomboid or triangular. In order to maximise the surface area of photocatalytic material exposed to direct UV light radiation the tapered protrusions preferably have an external form with flat or rounded surfaces. Advantageously the tapered protrusions may have a conical form. Advantageously the form of the reactor unit according to the present invention permits a high air flow rate, e.g. of 20 to 100 m^lh, whilst maintaining a low pressure loss e.g. less than 300 Pa. According to a particular feature of the invention the catalytic material support is constructed from a single sheet of flexible material. The tapered protrusions are formed integrally from the sheet of flexible material and the sheet is folded to form a tubular shape. The catalytic material support may advantageously be formed from a sheet of flexible plastics material, e.g. polystyrene, polyvinyl chloride, acrylonitrile butadiene styrene, polyethylene, polyethylene terephtalate, polymethyl methacrylate; but also a sheet of metal e.g. steel, aluminium or a sheet of mineral, vegetal or plastic fibers. The tapered portions can advantageously be easily and economically integrally formed from a sheet of flexible plastics material by moulding or thermofomning, for instance. Accordingly, no complex tool or procedure is required for the manufacture of the catalyser device. The photocatalytic material may advantageously be applied to the catalytic material support before the support is folded to form a tube. For instance the photocatalytic material may be painted or sprayed onto the surface of the catalytic material support sheet before folding of the support to form a tube. Advantageously the photocatalytic material may be sprayed onto the catalytic material support sheet by a mechanised spraying system substantially only to the area under illumination thus reducing waste. The spraying system could be an automated spray system, making the application of the photocatalytic material to the reactor unit very simple and economic. The photocatalytic material may be any known photocatalytic material. Advantageously the photocatalytic material may comprise an inorganic binder including ultraviolet light permeable polymeric molecules, a polar diluent, and particles of an inorganic semi-conductor, the weight of the inorganic semi- conductor particles being two to twenty times less than the weight of both the diluent and binder. The inorganic semi-conductor may be for instance cadmium sulphide, zinc sulphide and/or titanium dioxide. Preferably the photocatalytic material comprises titanium dioxide. The polymeric molecules may include acrylic molecules. Advantageously a photocatalytic gel as described in WO 2007/060520, incorporated herein by reference may be used. Further disclosed herein is a reactor unit for photocatalytic treatment of fluids, for instance for cleaning and deodorising air, comprising a catalyser device comprising a catalytic material support having a generally tubular shape forming an air conduit and a photocatalytic material coated on at least a portion of an internal surface of the support, a housing having a tubular body with a cavity for receiving the catalyser device, a radiation source received in a central portion of the catalyser device, an air inlet module, an air outlet module and a filter comprising one or more metal components having fluid purifying activity mounted in at least one of the fluid inlet and air outlet modules. The metal may be for instance a metal that has germicide activity, such as copper, silver or zinc or a reactive metal that has activity for converting noxious chemicals into compounds harmless to the human organism, e.g. which can act to convert carbon monoxide to carbon dioxide, such as gold, platinum, palladium, rhodium, or zirconium. Advantageously the filter may be in the form of a foam, e.g. formed from a plastics or metallic material, with the one or more metal components having air purifying activity coated thereon. The filter component may advantageously provide further enhanced fluid purification properties of the reactor unit, e.g. with respect to certain pathogens e.g. bacteria, and with respect to removing certain noxious compounds such as carbon monoxide. Further described herein is a reactor unit for photocatalytic treatment of fluids, for instance for cleaning and deodorising air, comprising a catalyser device comprising a catalytic material support having a generally tubular shape forming an air conduit and a photocatalytic material coated on at least a portion of an internal surface of the support, a radiation source received in a central portion of the catalyser device, a fluid inlet module and a fluid outlet module, wherein at least one of the fluid inlet module and air outlet module comprises a radiation baffle having multiple fluid-flow passages. The radiation baffle may advantageously comprise multiple concentric S-shaped vanes running from an axially interior surface to an exterior surface of the inlet and/or outlet modules. The radiation baffle acts to prevent ultraviolet light emitted by the radiation source from being visible outside of the fluid inlet module and fluid outlet module reactor. Advantageously the radiation baffle effectively minimises or eliminates the direct emission of the ultraviolet light emitted by the radiation source outside the reactor unit. Accordingly the reactor unit may be used in any environment without requiring an additional cover or outer housing, making the reactor unit easy and safe to use. Objects of this invention are also achieved by an apparatus for cleaning and deodorising air according to claim 22. There is provided an apparatus for photocatalytic treatment of fluids, for instance for cleaning and deodorising air, comprising a reactor unit as disclosed herein and a drive unit to which the reactor unit is removably connected. The drive unit comprises a power source for providing electrical power to the radiation source, and a fluid flow system for propelling or drawing fluid through the reactor unit. Advantageously the removable connection between the reactor unit and the drive unit is provided by complimentary quarter-turn electrical connectors on the drive unit and reactor unit. Accordingly the reactor units may be easily and conveniently attached and removed from the drive unit such that they may be easily and conveniently replaced during the life of the apparatus. The use of a quarter turn electrical connector on the reactor unit allows simple and easy connection of the reactor units into a fluid purification system. There is also disclosed an apparatus for cleaning and deodorising large volumes of gaseous fluid comprising a plurality of the reactor units grouped together in a single unit or housing. Advantageously the reactor unit and apparatus according to the present invention provides for effective and efficient photocatalytic treatment of fluids, for instance cleaning and deodorising of air. Advantageously, the fact that the all of the parts of the reactor unit may be simply and economically manufactured means that the reactor unit may be easily and economically replaced. The ability to easily and economically change the reactor unit enables apparatus to have a long operation lifetime, whilst at the same time ensuring continued effective cleaning and deodorizing properties in an economic manner. The compact and modular nature of reactor unit enables it to be easily integrated into a fluid treatment apparatus with a single reactor unit or with a plurality of reactor units, depending on the volume of fluid to be treated. The reactor units may advantageously for the purification treatment of air (cleaning, sterilising and deodorising) in various environments such as in households, offices, factories, and hospitals. The particularly compact arrangement and efficient and effective operation of the reactor unit, as well as its low weight, also enables it to be advantageously used in aircraft and automobiles for cleaning, sterilising and deodorising air. The reactor unit may also be used for the photocatalytic treatment of many other gases or mixture of gases for various applications in industry, for example purification of nitrogen or carbon dioxide for the food and beverage industry, deodorisation of effluents, treatment of ultra pure air in electronic or pharmaceutical clean rooms. Further objects and advantageous aspects of the invention will be apparent from the claims and the following detailed description of an embodiment of the invention in conjunction with the drawings in which: Figure 1 is a cross-section view of a reactor unit for photocatalytic treatment of gaseous fluids according to an embodiment of tine present invention; Figure 2 is perspective exploded view of a reactor unit for photocatalytic treatment of gaseous fluids according to an embodiment of the present invention; Figure 3a is a perspective view of a catalytic device according to an embodiment of the present invention; Figure 3b is a cross-section view of a catalytic device according to the above embodiment of the invention; Figure 3c is a cross-section view of a catalytic device according to another embodiment of the invention; Figure 4a is a perspective view of a catalytic material support formed from a sheet of flexible material according to an embodiment of the present invention in an unfolded state; Figure 4b is a detailed perspective view of a portion of the catalytic material support shown in Fig. 4a; Figure 5 is a schematic view of a tapered protrusion according to an embodiment of the present invention Figure 6a is a cross-section view of a radiation baffle according to the present invention; Figure 6b is a cut-out perspective view of a radiation baffle according to the present invention. Figure 7a is a perspective view of a reactor and a connector element according to an embodiment of the present invention; Figure 7b is a perspective view of a connector element according to an embodinnent of the present invention; Figures 8a to 8c are perspective views of apparatus for plnotocatalytic treatment of gaseous fluids according to further embodiments of the present invention. Referring to the figures, in particular figures 1 and 2, a reactor unit 1 for photocatalytic treatment of gaseous fluids according to the present invention includes a housing 2, a catalyser device 4 removably mounted in the housing, an ultraviolet radiation source received centrally in the catalyser device, a fluid inlet module 10 and a fluid outlet module 20. It is understood that the fluid inlet module and fluid outlet module may be reversed depending on the direction of the fluid-flow through the reactor unit. The catalyser device 4 comprises a catalytic material support 6, having a tubular shape defining a fluid flow channel extending around and along a fluid flow path. In the illustrated embodiment, the catalyser support material and the housing have a generally cylindrical shape. However, the catalytic support material and the housing may have any other generally tubular profile, such as elliptical or polygonal, depending on the arrangement of the ultraviolet radiation source and the projection of UV radiation therefrom. The tubular shape of the catalyser device preferably extends in an essentially linear general fluid flow direction F as shown in the embodiments illustrated, but could also extend in a generally curved or non linear manner (not shown). In the embodiment illustrated in figures 1 and 2 the fluid inlet module and fluid outlet module comprise the same functional units of a radiation baffle 12, a metallic filter 18 and a filter support 24. The fluid outlet 20 further includes a cover piece 26 which can be used as print support. Referring particularly to Figures 1, 3a-3c, the catalytic support material 6 comprises a wall portion 7 and a plurality of tapered protrusions 8. The tapered protrusions have a base portion 5, on an internal surface 21 of the wall portion of the catalytic material support, and a tip 3 proximate to the radiation source 30. The radiation source is preferably positioned along the central axis of the catalyser device. The ultraviolet radiation source may conveniently be one or more UV lamps, for instance a low or medium pressure mercury lamp, an incandescent lamp or a fluorescent lamp. It may have a cylindrical shape, a bulb shape or any other shape. Conveniently the radiation source may be one or more single or multiple UV tube lamps. In the illustrated embodiment the radiation source is a double tube UV lamp, which has the advantage of proving a high level of UV irradiation for a relatively short length of radiation source, and usefully allows for a single point of electrical connection. Advantageously the ultraviolet radiation source generates light having a wavelength between 180 and 420nm, preferably between 240 and 390nm, e.g. 250 to 260 nm. Preferably the ultraviolet radiation source generates light having a wavelength of 254 nm. The use of ultraviolet light having a wavelength of 254nm has been found to provide particularly effective germicide and photocatalytic activation properties. Use of light having a wavelength of 254nm advantageously allows the production of ozone to be avoided. The tips of the tapered protrusions may be located at a position within a range of 0 (i.e. touching the surface of the radiation source) to a distance of less than 50%, preferably less than 30%, the distance separating the surface 31 of the radiation source 30 and the internal surface 21 of the catalytic device wall portion. The tips of the tapered protrusions extend from the internal surface of the catalytic material support 7 to a position near to or touching the radiation source 30. The tips of some or all of the tapered protrusions may abut an external surface of the radiation source. The extremity of the tips of one or more tapered protrusions may be located, for instance, at a distance of 0 to 20mm from an external surface of the radiation source, preferably 0 to 10mm, more preferably 2 to 5mm. The provision tapered protrusions that extend from an internal wall of the catalyser device to a position near to or touching the radiation source advantageously acts to provide a meandering non-laminar flow-path of the fluid flowing through the reactor unit, ensuring a thorough mixing of the fluid, and ensuring that all of the fluid flowing through the reactor unit is contacted with the photocatalytic material and exposed to UV radiation from the radiation source. Preferably the tapered protrusions extend substantially perpendicularly from the internal surface 21 of the wall portion towards the radiation source 30 positioned centrally in the catalyser device, in order to avoid or minimise any areas of the intemal surface of the catalytic material support that may be shaded from direct exposure to UV radiation from the radiation source. Advantageously the tapered protrusions extend substantially perpendicularly from the wall portion to a central axis of the radiation source. In this way the surface area of the catalytic material support exposed to direct ultraviolet radiation from the ultraviolet radiation source may be maximised. Where the radiation source is in the form of a plurality of UV radiation sources, e.g. a multi-tube ultraviolet lamp, the tapered protrusions positioned around the internal surface of the catalyser device may point towards a central axis where the radiation source is positioned. Figure 3b shows a possible arrangement of the tapered protrusions 8 around the circumference of the intemal surface of a catalyser device 4 according to an embodiment of the present invention. In the embodiment illustrated the catalytic support material 6 is configured to receive a double-tube UV lamp along a central axis of the catalyser device. In Figure 3b the tips of the tapered protrusions 8 point towards the central axis of the catalyser device which constitutes also the central axis of the double-tube UV lamp radiation source when inserted in the catalyser device. It is also envisaged that the tips of the tapered protrusions may point towards the central axis of each of the UV tubes, i.e. as indicated by the numerals 32 in Figure 3b. The tapered protrusions within one catalyser device may have different lengths, for instance dependant on the form of the radiation source received in the catalyser device. Preferably the distance between the radiation source and the irradiated surface of the internal wall portion of the catalytic support material is between 20mm to 70mm, preferably between 30mm to 55mm to optimise the overall effectiveness of the photocatalytic activity on fluid passing therethrough. The plurality of tapered protrusions may be arranged in a regular arrangement around the internal surface of the catalyser device, for instance in a series of regularly spaced rows. Preferably the tapered protnjsions may be arranged in stepped rows around the internal surface of the catalytic material support, such that the tapered protrusions in each row around the circumference of catalyser device are not aligned with the tapered protrusions in the adjacent circumferential rows along the direction of fluid flow through the reactor unit. In other words, tapered protrusions at different positions along the fluid flow channel are arranged in an angularly offset manner around the internal surface of the catalytic material support. According to a preferred embodiment the tapered protrusions within a row are equally spaced apart and the rows are equally spaced along the length of the catalyser device. Preferably each row of tapered protrusions is displaced by a half step relative to the adjacent row, whereby a step corresponds to the distance between adjacent protrusions in a row. Such a stepped arrangement of the tapered protrusions advantageously provides effective mixing of the fluid flowing through the reactor unit. Preferably the tapered protrusions 8 have a conical form, which advantageously allows a relatively natural flow of the fluid through the reactor unit and accordingly minimising the charge loss. The base portion 5 of tapered protrusions preferably has a substantially circular shape for enabling easy manufacture of the tapered protrusions. Other shapes for the base portion of the tapered protrusions may be envisaged, such as, for instance circular, oval, hexagonal, octagonal, rhomboid or triangular. The tips of the tapered protrusion may have, for instance, a pointed, truncated or rounded form. The tips of the tapered protrusions preferably have a small cross- section area in order to minimise the surface area of the radiation source which is obstructed by the tips of the protrusions, thus ensuring that a maximum amount of the irradiation from the radiation source reaches the rest of the surface of the catalytic material support. The tapered protrusions may preferably have an average height h to average maximum base diameter d ratio of 6:1 to 1:1, preferably of 4:1 to 2:1. The height of a tapered protrusion is here measured form the radially innermost point of the tip to the radially outermost point of the base portion. The largest base diameter is here measured as the maximum distance measured across the cross section of the base portion of the protrusion. The tapered protrusions preferably have an internal taper angle a of 1 to 30°, preferably 1 to 15°, for example 5 to 15°. Accordingly, the balance between the number of protrusions within the catalyser device, providing a large surface area of photocatalytic material, and the provision of a sufficient direct irradiation of the surface of the catalyser support material by the UV radiation source may be optimised. As illustrated in figure 3c, it is possible to provide in addition certain other protrusions 19 extending from the internal surface 21 of the wall portion to a tip 23 that is not proximate to the radiation source, such that the inner surface of the catalytic device comprises both long and short protrusions in view of increasing radiated catalyser surface area and to increase fluid flow contact with catalyser surface area near the base of the protrusions. At least a portion of the Internal surface of the catalytic material support is coated with a photocatalytic material. Preferably substantially the whole of the internal surface of the catalytic material support which is irradiated with ultraviolet light from the ultraviolet radiation source is coated with photocatalytic material. The photocatalytic material may be any known photocatalytic material. Preferably the photocatalytic material comprises particles of inorganic semi-conductor, particularly, cadmium sulphide, zinc sulphide and/or titanium dioxide in anatase crystalline form. Preferably the photocatalytic material comprises titanium dioxide in view of its effective catalytic activity in the presence of ultraviolet light, its stability, and its harmlessness to the human organism. In a particular embodiment of the present invention the photocatalytic material comprises an inorganic binder including ultraviolet light permeable polymeric molecules, a polar diluent, and particles of an inorganic semi-conductor, the weight of the inorganic semi-conductor particles being two to twenty times less than the weight of both the diluent and binder. The polymeric molecules preferably include acrylic molecules. Advantageously a photocatalytic gel as described in WO 2007/060520 may be used. Such a photocatalytic gel material exhibits good adhesion to many types of materials, and advantageously can be dried in air with out the need for high temperature treatment, thus allowing the coating of materials that do not support high temperatures such as plastics. The photocatalytic material is applied onto an internal surface of the photocatalytic support material in order to use its photocatalytic properties to treat gases, such as clean and deodorize air. Advantageously the photocatalytic material may be in a liquid or gel form for easy application to the catalytic support material. The photocatalytic material may conveniently be applied to the catalytic material support for instance by spraying or painting of the gel or liquid on to a surface of the support, or by immerging the support into a receptacle containing the photocatalytic material. The catalytic material support may advantageously be formed from a plastics material, e.g. polystyrene, polyvinyl chloride, acrylonitrile styrene, polyethylene, polyethylene terephtalate, polymethyl methacrylate.. The tapered protrusions and the wall portion of the catalytic material support may be manufactured separately, for example by injection moulding or extrusion moulding, and bonded, welded, glued or othenA/ise fixed together but preferably the tapered protrusions are formed integrally with the wall portion. Referring particularly to Figure 4a, according to a particular feature of the invention the catalytic material support 6 may be constructed from a single sheet of flexible material. The tapered portions can be easily and economically integrally formed from a sheet of flexible plastics material by thermoforming or moulding or by other standard methods. The flexible plastics material may be for example polystyrene, polyvinyl chloride, acrylonitrile styrene, polyethylene, polyethylene terephtalate or polymethyl methacrylate. The sheet of flexible material with the integrally formed tapered protrusions is then bent into a tubular shape and may be welded, crimped, bonded or held together by mechanical clamps along its seam to form a tube, or simply held in an outer support tube without being held together along its seam. The sheet may be provided with grooves or indents 9, as best seen in Fig. 4b, that ease the bending of the sheet into a tubular shape, and improve the reproducibility of the tubular shape. It is preferred to form the catalytic device from a single sheet, however within the scope of the invention, it is also possible to form the catalytic device from two or more sheets welded, bonded or fixed along their edges to each other by mechanical means (such as rivets or clamps). The two or more sheets could also be assembled without being bonded together, in a tubular housing of the reactor unit that positions and supports the sheets such that they collectively form a tube around the radiation source. The photocatalytic material may advantageously be applied to the catalytic material support before the support is folded to form a tube. For instance the photocatalytic material may be painted or sprayed onto the surface of the catalytic material support sheet before folding of the support to form a tube. Advantageously the photocatalytic material may be sprayed onto the catalytic material support sheet by a mechanised spraying system, e.g. an automated spray system, making the application of the photocatalytic material to the reactor unit very simple and economic. Where the catalytic support material is produced from a single sheet of flexible material the tapered protrusions should be spaced sufficiently far apart to allow bending of the sheet to form a tube. The spacing required will depend, amongst other things on the diameter of the catalyser device and the relative size of the protrusions. Where the tapered protrusions are formed integrally from the sheet of flexible material by a method such as thermoforming it is necessary that the base portion protrusions encompass a sufficient amount of the plastics material to enable the forming of the tapered protrusion. Preferably the protrusions have an average height h to average maximum base diameter d ratio 4:1 to 2:1. The catalytic support according to the invention can thus be made particularly lightweight, while providing very efficient treatment due to the high actively radiated surface and effective aerodynamics of the tapered protrusions. This advantageously enables the reactor units according to the invention to be used in mobile applications such as in aeroplanes or automobiles, or for use in mobile or even portable fluid treatment apparatus. The reactor unit may further comprise a radiation baffle in at least one of the fluid inlet module 10 and fluid outlet module 20, in order to prevent the ultraviolet radiation source from being visible outside the reactor unit. In the embodiment illustrated in Figures 1 and 2, the fluid inlet module 10 and fluid outlet module 20 include a radiation baffle 12 with multiple fluid-flow passages. Referring to Figures 6a and 6b, the radiation baffle may advantageously comprise multiple concentric S-shaped vanes 15. The radiation baffle may be provided as a single unit. Alternatively the radiation baffle may be manufactured as separate units which may then be mounted or connected together in the fluid inlet and/or fluid outlet module. In the illustrated embodiment the radiation baffle is comprised of two separate radiation baffle units 13 and 14 which may be manufactured simply and economically e.g. from a plastics material by standard methods such as injection moulding. The radiation baffle may conveniently be manufactured from a plastics material such as polyethylene, polybutadiene terephtalate, acrylonitrile butadiene styrene, polymethyl methacrylate, polyvinyl chloride, fibre-glass mineral or cellulosic type polymers. Advantageously the radiation baffle effectively minimises or eliminates the direct emission of the ultraviolet light emitted by the radiation source outside the reactor unit. Accordingly the reactor unit may be used in any environment without requiring an additional cover or outer housing, making the reactor unit easy and convenient to use. In the illustrated embodiment the radiation baffle 12 in the fluid inlet module 10 also acts as a filter to remove insects, large particles and dust. Alternatively, the reactor unit may include a separate filter at its inlet. In the embodiment illustrated in Figures 1 and 2, the fluid inlet module 10 and fluid outlet module 20 comprise a metallic filter 18 to provide further improved fluid purification. The filter comprises one or more metal components having fluid purifying activity. The metal may be a metal that has germicide activity, such as copper, silver or zinc, or a reactive metal that has activity for converting noxious chemicals into compounds harmless to the human organism, e.g. which can act to convert carbon monoxide to carbon dioxide, such as gold, platinum, palladium, rhodium or zirconium. In the illustrated embodiment the fluid purification active metal is provided on a separate filter component 18. It is also envisaged that the metal component may be provided on the surface of a component of the reactor unit, for instance as a coating, on the surface of the radiation baffle 12. The filter may also be formed from metal wire for instance as a gauze or fibre-glass type structure. According to a preferred embodiment the filter 18 may have an open-cell foam type structure, e.g. with at least 70%, preferably more than 80% space. Advantageously such a foam-type filter provides a large surface area of for filter for contact with the fluid flowing through the reactor unit whilst minimising charge loss. The filter may be formed from a plastics or metallic material, with the one or more metal components having fluid purifying activity coated on the surface thereof. The metallic filter component advantageously provides further enhanced the fluid purification properties of the reactor unit, e.g. with respect to certain pathogens such bacteria, and with respect to removing certain noxious compounds such as carbon monoxide. The reactor unit of the present invention may easily and conveniently be used in systems for air purification. Figures 8a to 8c show schematic illustrations of some possible air purification systems 50, 60 using the reactor unit of the present invention. The purification systems include a drive unit to which one or more reactor units according to the present invention are removably connected. The drive unit comprises an electrical connector for providing current to the radiation source electrical connector 31, and a fluid flow system for propelling or drawing air through the reactor unit. The drive unit may be configured for connection to the mains electrical network or may, for instance, be battery powered. For instance the drive unit may include a connection member 40 with socket connectors 42 into which the electrical pin connectors of the radiation source 31 are received. Electrical connection may be effected by inserting the connection member 40 into the fluid inlet 10 or fluid outlet module of the reactor unit. Advantageously the removable connection between the reactor unit and the drive unit is provided by a quarter-turn electrical connection, whereby the connection member is inserted into tlie reactor unit and rotated to bring the electrical connector in the socket connectors 42 into electrical contact with the radiation source electrical pin connectors 31. The connection member or the reactor unit may comprise complimentary locking means 44 to limit the rotation of the connection member 40 with respect to the reactor unit and/or to hold the reactor unit and connection member together. The use of a quarter tum electrical connector on the reactor unit advantageously allows simple and easy connection of the reactor units into a fluid purification system. Figure 8c shows an apparatus 60, designed for the cleaning and deodorising of large volumes of air or other gases according to the present invention in which may a plurality of the reactor units 1 are grouped together in a single housing 62. The compact and modular nature of the reactor unit enables it to be easily integrated into a fluid treatment apparatus 50 having a housing 51 receiving a single reactor unit 1 or with a plurality of reactor units, depending on the volume of fluid to be treated. The apparatus housing may comprise an air inlet grill 54 and user interface screen or display 52 providing information on the usage of the apparatus and maintenance requirements, such as need for replacement of the reactor unit, radiation source and/or catalytic device. The reactor units may advantageously be used in an apparatus for the purification treatment of air (cleaning, sterilising and deodorising) in households, offices, factories, and hospitals. The particularly compact arrangement and efficient and effective operation of the reactor unit also enables it to be advantageously used in aircraft and automobiles for cleaning, sterilising and deodorising air. The reactor unit may also be used for the photocatalytic treatment of many other gases or mixture of gases for various applications. For instance, the reactor unit may be used for purifying gases such as nitrogen or carbon dioxide used in the food and beverages industry for food preservation, deodorising gaseous effluents or treat ultra-pure air in electronic or pharmaceutical clean rooms. Claims 1. A reactor unit for photocatalytic treatment of fluids including a housing, a catalyser device comprising a catalytic material support having a generally tubular shape defining a fluid flow channel extending around and along a fluid flow path and a photocatalytic material coated on at least a portion of an internal surface of the support, and a radiation source received in a central portion of the catalyser device, wherein the catalytic material support comprises a wall portion and a plurality of tapered protrusions extending from an internal surface of the wall portion to a tip positioned at a distance to the radiation source within a range of 0 to 50% the distance separating the radiation source and the internal surface of the wall portion, the tapered protrusions being arranged around the radiation source and along the fluid flow channel. 2. A reactor unit according to claim 1 wherein the tips of the tapered protrusions are within a range of 0 to 30% the distance separating the radiation source and the internal surface of the wall portion. 3. A reactor unit according to claim 1 or 2 wherein the tapered protrusions extend substantially perpendicularly from the internal surface of the catalytic material support wall portion towards a central axis of the radiation source. 4. A reactor unit according to claim 1, 2 or 3 wherein the tapered protrusions have an average height to average base diameter ratio in a range from 6:1 to 1:1. 5. A reactor unit according to any one of claims 1 to 4 wherein the tapered protrusions have a generally conical form. 6. A reactor unit according to any one of the preceding claims wherein tapered protrusions at different positions along the fluid flow channel are arranged in an angularly offset manner around the internal surface of the catalytic material support. 7. A reactor unit according to any one of the preceding clainns wherein the catalytic material support is formed from a sheet of flexible material folded to form a tubular shape, and the tapered protrusions are formed integrally from the sheet of flexible material. 8. A reactor unit according to claim 7 wherein the catalytic material support is formed from a plastics material. 9. A reactor unit according to claim 7 or 8 wherein the tapered protrusions are formed by moulding, extrusion orthermoforming of the sheet of flexible material. 10. A reactor unit according to any one of the preceding claims wherein the radiation source is in the form of one or more UV light tubes. 11. A reactor unit according to any one of the preceding claims wherein the housing comprises a generally tubular body with a cavity for receiving the catalyser device. 12. A reactor unit according to any one of the preceding claims further comprising a fluid inlet module, a fluid outlet module and a filter comprising one or more active metal components mounted in at least one of the fluid inlet and fluid outlet modules. 13. A reactor unit for photocatalytic treatment of fluids including a catalyser device comprising a catalytic material support having a generally tubular shape forming a fluid conduit and a photocatalytic material coated on at least a portion of an internal surface of the support, a radiation source received in a central portion of the catalyser device, a fluid inlet module, a fluid outlet module and a filter comprising one or more active metal components mounted in at least one of the fluid inlet and fluid outlet modules. 14. A reactor unit according to claim 13 wherein the filter is in the form of a plastic foam having an open pore structure coated with an active metal. 15. A reactor unit according to claim 13 or 14 wherein the active metal is selected from the group comprising silver, copper, gold, platinum, zinc, palladium, rhodium or zirconium. 16. A reactor unit for photocatalytic treatment of fluids including a catalyser device comprising a catalytic material support having a generally tubular shape forming an fluid conduit and a photocatalytic material coated on at least a portion of an internal surface of the support, a radiation source received in a central portion of the catalyser device, a fluid inlet module and a fluid outlet module, wherein at least one of the fluid inlet module and fluid outlet module comprises and a radiation baffle having multiple fluid-flow passages. 17. A reactor unit according to claim 16 wherein the fluid-flow passages of the radiation baffle are formed by multiple concentric S-shaped vanes running from an axially interior surface to an exterior surface of at least one of the inlet and outlet modules. 18. A reactor unit according to any one of claims 13 to 17, wherein the catalytic material support comprises a wall portion and a plurality of tapered protrusions extending substantially perpendicularly from a base on an interior surface of the wall portion to a tip proximate to the radiation source. 19. A reactor unit according to claim 18 further comprising any one or more of the additional features of the reactor unit according to any one of claims 1 to 11. 20. A catalyser device comprising a catalytic material support and a photocatalytic material coated on at least a portion of a side of the support, the support comprising a single sheet of a flexible material folded to form a generally tubular shape or a portion of a generally tubular shape and plurality of tapered protrusions extending from one face of the sheet of flexible material and formed integrally from the sheet of flexible material. 21. A catalyser device according to claim 20 wherein the catalytic material support is formed from a plastics material. 22. A catalyser device according to any of claims 20 or 21 wherein the tapered protrusions are formed by moulding or thermoforming of the sheet of flexible material. 23. An apparatus for photocatalytic treatment of fluid, such as for cleaning and deodorising air, comprising a reactor unit according to any one of claims 1 to 19 and a drive unit to which the reactor unit is removably connected, said drive unit comprising a power source for providing electrical power to the radiation source, and a fluid flow system for propelling or drawing fluid through the reactor unit. 24. An apparatus for photocatalytic treatment of fluid according to claim 23 wherein the removable connection between the reactor unit and the drive unit is provided by complimentary quarter-turn electrical connector. 25. An apparatus for photocatalytic treatment of fluid according to claim 23 or 24 comprising a plurality of drive units mounted on a common support and a corresponding plurality of reactor units coupled to respective drive units. 26. A method of making a catalyser device comprising moulding or thermoforming a plurality of tapered protrusions out of a sheet of polymeric material, coating at least a portion of a side of the sheet with a photocatalytic material, and forming a generally tubular shape from one or more said sheets of polymeric material. 27. The method of claim 26 wherein the photocatalytic material is applied to the sheet of polymeric material before the support is folded to form a tube. 28. The method of claim 27 wherein the photocatalytic material is sprayed by an automated spray system onto the surface of the sheet. A reactor unit tor photocalalytic treatment of fluids such as air. includes a catalyse: device (4) comprising a catalytic material support having a generally tubular shape defining a fluid flow channel extending around and along a fluid flow path and a photocatalytic material coated on at least a portion of an internal surface of the support, and a radiation source (30) received in a central portion of the eatalyser device. The catalytic material support comprises a wall portion and a plurality of tapered protrusions (8) extending from an internal surface of the wall portion to a tip proximate to the radiation source, the tapered protrusions being arranged around the radiation source and alone the fluid flow channel.

Full Text

Device for photocatalytic treatment of fluids
The present invention relates to the field of devices for photocatalytic treatment of
fluids, for instance for cleaning, deodorizing and sterilizing gases such as air.
Nunnerous air purification systems have been described, or are commercially
available, which aim to remove various pollutants, such as dust, micro-particles,
noxious gases, allergens, and pathogenic micro-organisms from the air. In the
known systems, dust and other micro-particles are generally removed from the air
by the use of filters. It is known to remove certain volatile and reactive molecules
by the use of catalytic processes. The use of ultraviolet light radiation to inactivate
certain micro-organisms is also described. It is known to combine the use of
ultraviolet light and photocatalytic processes to accelerate the degradation of
noxious particles and the destruction of micro-organisms.
The use of photocatalysts in devices for deodorising or purifying air is described in
a number of patent applications, for example, US 5,670,126, US 6,558,639, US
2002/094298, US 6,358,374, US 2004/007453, JP 11226357, WO 02/085989, and
FR 2821558. The most common photocatalytic compound used in the known
systems is titanium dioxide because of its excellent photocatalytic activity when
irradiated with ultraviolet radiation, and its harmlessness to the human organism.
The photocatalyst is generally combined with a binder to form a photocatytic
coating material. A photocatalytic material which is convenient to use, adheres well
to a number of surface and may be applied to articles which do not support high
temperatures is described in WO 2006/010993, hereby incorporated herein by
reference. The photocatalytic material described in WO 2006/010993 comprises
an inorganic binder including ultraviolet light permeable polymeric molecules,
particularly acrylic molecules, a polar diluent, and particles of an inorganic semi-
conductor, such as cadmium sulphide, zinc sulphide or titanium dioxide.
In known systems the photocatalytic material is generally coated on a filter element
or other surfaces of the air purifying system irradiated by an ultraviolet light source,
typically an ultraviolet lamp. For example EP 0978690 and WO 96/37281 describe
systems in which air is passed through an air-permeable sheet supporting a
photocatalytic material and placed in the vicinity of an ultraviolet light source.
Such systems generally provide only limited air cleaning properties with respect to
removing certain airborne pollutants, allergens and pathogens.
A system with improved air cleaning properties is described by WO 2007/060520,
in which a photocatalytic material is coated on an inside surface of a tubular air
conduit containing a UV lamp. A number of spaced apart blades are located on the
inside surface of the air conduit in order to increase the surface area of
photocatalytic material in the air conduit and to create turbulent flow of the air
through the conduit.
EP 0470518 describes a system designed for the decomposition of organic
substances in which a liquid is passed through a stainless steel reaction vessel
containing an ultraviolet immersion lamp. According to EP 0470518 baffles are
located on the inner surface of the stainless steel tube to cause turbulence in the
flow of the liquid on the reaction vessel inner surface.
The known systems do however present a number of drawbacks. For instance the
known systems are generally relatively complex and costly to manufacture and/or
maintain. Moreover, the known systems either do not effectively treat all the air
passing through the device, and/or cause excessive resistance on the air passing
through with the consequence of increased noise and the need to employ more
powerful fans for a given rate of airflow.
There is also an ongoing need for air purification systems which reliably and
effectively remove, destroy or inactivate airborne pollutants, allergens and
pathogens.
It is an object of this invention to provide a device for use in the photocatalytic
treatment of fluids which provides reliable and effective treatment of said fluids and
which is economic to manufacture.
It would be advantageous to provide a reactor unit which provides reliable and
effective cleaning, deodorizing and sterilizing of air and which is economic to
manufacture.
It would be advantageous to provide an apparatus for the photocatalytic treatment
of fluids that has a low pressure loss for a given rate of treated fluid flow.
It would be advantageous to provide an apparatus for the photocatalytic treatment
of fluids that has low noise emission.
It would be advantageous to provide an apparatus for the photocatalytic treatment
of fluids that is easy to use and versatile.
It would be advantageous to provide an apparatus for the photocatalytic treatment
of fluids that is economic to manufacture, maintain and use.
It would be advantageous to provide an apparatus that can conveniently and
effectively be used in the photocatalytic treatment of large volumes of fluids.
Objects of the present invention are achieved by a reactor unit according to claim
1.
Disclosed herein is a reactor unit for photocatalytic treatment of fluids including a
catalyser device comprising a catalytic material support having a generally tubular
shape defining a fluid flow channel extending around and along a fluid flow path
and a photocatalytic material coated on at least a portion of an internal surface of
the support, and a radiation source received in a central portion of the catalyser
device. The catalytic material support comprises a wall portion and a plurality of
tapered protrusions extending from an internal surface of the wall portion to a tip
proximate to the radiation source, the tapered protrusions being arranged around
the radiation source and along the fluid flow channel.
The term "proximate" as used in the present application is meant within a range of
0 (i.e. touching) to a distance of less than 50% the distance separating the surface
of the radiation source and the internal surface of the catalytic device wall portion.
The tips of the tapered protrusions may be located at a position within a range of 0
(i.e. touching the surface of the radiation source) to a distance of less than 50%,
preferably less than 30%, the distance separating the surface of the radiation
source and the internal surface of the catalytic device wall portion. For instance,
the extremity of the tips of one or more tapered protrusions may be located at a
distance within a range of 0 to 20mm from an external surface of the radiation
source, preferably within a range of 0 to 10mm, more preferably within a range of 2
to 5 mm.
Advantageously the provision of a tubular catalytic material support with a plurality
of tapered protrusions extending from a wall portion of the catalytic material support
to a tip proximate to the radiation source not only provides a greatly increased
surface area of photocatalytic material inside the reactor unit, but also increases
the proportion of the coated internal surface of the catalyser device that is exposed
to direct ultraviolet light from the radiation source.
The plurality of tapered protrusions arranged around the inner periphery of the
generally tubular support and along its length in the fluid general flow direction also
provide a plurality of meandering paths for the fluid flow, thus increasing the
amount of fluid which is brought into contact with the photocatalytic material.
Further the arrangement of a plurality of tapered protrusions inside the reactor unit
extending to a tip proximate to the radiation source creates a certain amount of
turbulence to further increase the contact of air flowing through the reactor unit with
photocatalytic material, whilst maintaining a low pressure loss (low resistance) on
air flowing through system.
Preferably the tapered protrusions extend substantially perpendicularly from the
internal surface of the catalytic material support wall portion towards the radiation
source.
Advantageously having tapered protrusions around the internal surface of the
reactor inside the reactor which extend substantially perpendicularly towards a
central axis of the radiation source enables the surface area of the photocatalytic
material on the catalytic material support that is exposed to direct ultraviolet
radiation from the radiation source to be maximised.
The plurality of tapered protrusions may preferably be arranged in successive rows
around the internal surface of the catalytic material support, each offset at a certain
angle with respect to the previous row. Such a stepped (angularly offset)
arrangement of the tapered protrusions advantageously provides effective mixing
of the air flowing through the reactor unit.
Advantageously the tapered protrusions have an average height to largest base
diameter ratio of 6:1 to 1:1, preferably 4:1 to 2:1. In this way the surface area of the
photocatalytic material support and the distance between the radiation source and
the photocatalytic material may be optimised for effective and reliable treatment.
The base portion of the tapered protrusions may have any suitable cross-section
shape, for instance circular, oval, hexagonal, octagonal, rhomboid or triangular. In
order to maximise the surface area of photocatalytic material exposed to direct UV
light radiation the tapered protrusions preferably have an external form with flat or
rounded surfaces. Advantageously the tapered protrusions may have a conical
form.
Advantageously the form of the reactor unit according to the present invention
permits a high air flow rate, e.g. of 20 to 100 m^lh, whilst maintaining a low
pressure loss e.g. less than 300 Pa.
According to a particular feature of the invention the catalytic material support is
constructed from a single sheet of flexible material. The tapered protrusions are
formed integrally from the sheet of flexible material and the sheet is folded to form
a tubular shape.
The catalytic material support may advantageously be formed from a sheet of
flexible plastics material, e.g. polystyrene, polyvinyl chloride, acrylonitrile butadiene
styrene, polyethylene, polyethylene terephtalate, polymethyl methacrylate; but also
a sheet of metal e.g. steel, aluminium or a sheet of mineral, vegetal or plastic
fibers. The tapered portions can advantageously be easily and economically
integrally formed from a sheet of flexible plastics material by moulding or
thermofomning, for instance. Accordingly, no complex tool or procedure is required
for the manufacture of the catalyser device.
The photocatalytic material may advantageously be applied to the catalytic material
support before the support is folded to form a tube. For instance the photocatalytic
material may be painted or sprayed onto the surface of the catalytic material
support sheet before folding of the support to form a tube. Advantageously the
photocatalytic material may be sprayed onto the catalytic material support sheet by
a mechanised spraying system substantially only to the area under illumination
thus reducing waste. The spraying system could be an automated spray system,
making the application of the photocatalytic material to the reactor unit very simple
and economic.
The photocatalytic material may be any known photocatalytic material.
Advantageously the photocatalytic material may comprise an inorganic binder
including ultraviolet light permeable polymeric molecules, a polar diluent, and
particles of an inorganic semi-conductor, the weight of the inorganic semi-
conductor particles being two to twenty times less than the weight of both the
diluent and binder. The inorganic semi-conductor may be for instance cadmium
sulphide, zinc sulphide and/or titanium dioxide. Preferably the photocatalytic
material comprises titanium dioxide. The polymeric molecules may include acrylic
molecules. Advantageously a photocatalytic gel as described in WO 2007/060520,
incorporated herein by reference may be used.
Further disclosed herein is a reactor unit for photocatalytic treatment of fluids, for
instance for cleaning and deodorising air, comprising a catalyser device comprising
a catalytic material support having a generally tubular shape forming an air conduit
and a photocatalytic material coated on at least a portion of an internal surface of
the support, a housing having a tubular body with a cavity for receiving the
catalyser device, a radiation source received in a central portion of the catalyser
device, an air inlet module, an air outlet module and a filter comprising one or more
metal components having fluid purifying activity mounted in at least one of the fluid
inlet and air outlet modules.
The metal may be for instance a metal that has germicide activity, such as copper,
silver or zinc or a reactive metal that has activity for converting noxious chemicals
into compounds harmless to the human organism, e.g. which can act to convert
carbon monoxide to carbon dioxide, such as gold, platinum, palladium, rhodium, or
zirconium.
Advantageously the filter may be in the form of a foam, e.g. formed from a plastics
or metallic material, with the one or more metal components having air purifying
activity coated thereon.
The filter component may advantageously provide further enhanced fluid
purification properties of the reactor unit, e.g. with respect to certain pathogens e.g.
bacteria, and with respect to removing certain noxious compounds such as carbon
monoxide.
Further described herein is a reactor unit for photocatalytic treatment of fluids, for
instance for cleaning and deodorising air, comprising a catalyser device comprising
a catalytic material support having a generally tubular shape forming an air conduit
and a photocatalytic material coated on at least a portion of an internal surface of
the support, a radiation source received in a central portion of the catalyser device,
a fluid inlet module and a fluid outlet module, wherein at least one of the fluid inlet
module and air outlet module comprises a radiation baffle having multiple fluid-flow
passages.
The radiation baffle may advantageously comprise multiple concentric S-shaped
vanes running from an axially interior surface to an exterior surface of the inlet
and/or outlet modules.
The radiation baffle acts to prevent ultraviolet light emitted by the radiation source
from being visible outside of the fluid inlet module and fluid outlet module reactor.
Advantageously the radiation baffle effectively minimises or eliminates the direct
emission of the ultraviolet light emitted by the radiation source outside the reactor
unit. Accordingly the reactor unit may be used in any environment without requiring
an additional cover or outer housing, making the reactor unit easy and safe to use.
Objects of this invention are also achieved by an apparatus for cleaning and
deodorising air according to claim 22.
There is provided an apparatus for photocatalytic treatment of fluids, for instance
for cleaning and deodorising air, comprising a reactor unit as disclosed herein and
a drive unit to which the reactor unit is removably connected. The drive unit
comprises a power source for providing electrical power to the radiation source,
and a fluid flow system for propelling or drawing fluid through the reactor unit.
Advantageously the removable connection between the reactor unit and the drive
unit is provided by complimentary quarter-turn electrical connectors on the drive
unit and reactor unit.
Accordingly the reactor units may be easily and conveniently attached and
removed from the drive unit such that they may be easily and conveniently
replaced during the life of the apparatus. The use of a quarter turn electrical
connector on the reactor unit allows simple and easy connection of the reactor
units into a fluid purification system.
There is also disclosed an apparatus for cleaning and deodorising large volumes of
gaseous fluid comprising a plurality of the reactor units grouped together in a single
unit or housing.
Advantageously the reactor unit and apparatus according to the present invention
provides for effective and efficient photocatalytic treatment of fluids, for instance
cleaning and deodorising of air.
Advantageously, the fact that the all of the parts of the reactor unit may be simply
and economically manufactured means that the reactor unit may be easily and
economically replaced. The ability to easily and economically change the reactor
unit enables apparatus to have a long operation lifetime, whilst at the same time
ensuring continued effective cleaning and deodorizing properties in an economic
manner.
The compact and modular nature of reactor unit enables it to be easily integrated
into a fluid treatment apparatus with a single reactor unit or with a plurality of
reactor units, depending on the volume of fluid to be treated. The reactor units may
advantageously for the purification treatment of air (cleaning, sterilising and
deodorising) in various environments such as in households, offices, factories, and
hospitals. The particularly compact arrangement and efficient and effective
operation of the reactor unit, as well as its low weight, also enables it to be
advantageously used in aircraft and automobiles for cleaning, sterilising and
deodorising air.
The reactor unit may also be used for the photocatalytic treatment of many other
gases or mixture of gases for various applications in industry, for example
purification of nitrogen or carbon dioxide for the food and beverage industry,
deodorisation of effluents, treatment of ultra pure air in electronic or pharmaceutical
clean rooms.
Further objects and advantageous aspects of the invention will be apparent from
the claims and the following detailed description of an embodiment of the invention
in conjunction with the drawings in which:
Figure 1 is a cross-section view of a reactor unit for photocatalytic treatment of
gaseous fluids according to an embodiment of tine present invention;
Figure 2 is perspective exploded view of a reactor unit for photocatalytic treatment
of gaseous fluids according to an embodiment of the present invention;
Figure 3a is a perspective view of a catalytic device according to an embodiment of
the present invention;
Figure 3b is a cross-section view of a catalytic device according to the above
embodiment of the invention;
Figure 3c is a cross-section view of a catalytic device according to another
embodiment of the invention;
Figure 4a is a perspective view of a catalytic material support formed from a sheet
of flexible material according to an embodiment of the present invention in an
unfolded state;
Figure 4b is a detailed perspective view of a portion of the catalytic material support
shown in Fig. 4a;
Figure 5 is a schematic view of a tapered protrusion according to an embodiment of
the present invention
Figure 6a is a cross-section view of a radiation baffle according to the present
invention;
Figure 6b is a cut-out perspective view of a radiation baffle according to the present
invention.
Figure 7a is a perspective view of a reactor and a connector element according to
an embodiment of the present invention;
Figure 7b is a perspective view of a connector element according to an
embodinnent of the present invention;
Figures 8a to 8c are perspective views of apparatus for plnotocatalytic treatment of
gaseous fluids according to further embodiments of the present invention.
Referring to the figures, in particular figures 1 and 2, a reactor unit 1 for
photocatalytic treatment of gaseous fluids according to the present invention
includes a housing 2, a catalyser device 4 removably mounted in the housing, an
ultraviolet radiation source received centrally in the catalyser device, a fluid inlet
module 10 and a fluid outlet module 20. It is understood that the fluid inlet module
and fluid outlet module may be reversed depending on the direction of the fluid-flow
through the reactor unit.
The catalyser device 4 comprises a catalytic material support 6, having a tubular
shape defining a fluid flow channel extending around and along a fluid flow path. In
the illustrated embodiment, the catalyser support material and the housing have a
generally cylindrical shape. However, the catalytic support material and the
housing may have any other generally tubular profile, such as elliptical or
polygonal, depending on the arrangement of the ultraviolet radiation source and the
projection of UV radiation therefrom. The tubular shape of the catalyser device
preferably extends in an essentially linear general fluid flow direction F as shown in
the embodiments illustrated, but could also extend in a generally curved or non
linear manner (not shown).
In the embodiment illustrated in figures 1 and 2 the fluid inlet module and fluid
outlet module comprise the same functional units of a radiation baffle 12, a metallic
filter 18 and a filter support 24. The fluid outlet 20 further includes a cover piece 26
which can be used as print support.
Referring particularly to Figures 1, 3a-3c, the catalytic support material 6 comprises
a wall portion 7 and a plurality of tapered protrusions 8. The tapered protrusions
have a base portion 5, on an internal surface 21 of the wall portion of the catalytic
material support, and a tip 3 proximate to the radiation source 30.
The radiation source is preferably positioned along the central axis of the catalyser
device. The ultraviolet radiation source may conveniently be one or more UV
lamps, for instance a low or medium pressure mercury lamp, an incandescent lamp
or a fluorescent lamp. It may have a cylindrical shape, a bulb shape or any other
shape. Conveniently the radiation source may be one or more single or multiple
UV tube lamps. In the illustrated embodiment the radiation source is a double tube
UV lamp, which has the advantage of proving a high level of UV irradiation for a
relatively short length of radiation source, and usefully allows for a single point of
electrical connection.
Advantageously the ultraviolet radiation source generates light having a
wavelength between 180 and 420nm, preferably between 240 and 390nm, e.g. 250
to 260 nm. Preferably the ultraviolet radiation source generates light having a
wavelength of 254 nm. The use of ultraviolet light having a wavelength of 254nm
has been found to provide particularly effective germicide and photocatalytic
activation properties. Use of light having a wavelength of 254nm advantageously
allows the production of ozone to be avoided.
The tips of the tapered protrusions may be located at a position within a range of 0
(i.e. touching the surface of the radiation source) to a distance of less than 50%,
preferably less than 30%, the distance separating the surface 31 of the radiation
source 30 and the internal surface 21 of the catalytic device wall portion. The tips
of the tapered protrusions extend from the internal surface of the catalytic material
support 7 to a position near to or touching the radiation source 30. The tips of
some or all of the tapered protrusions may abut an external surface of the radiation
source. The extremity of the tips of one or more tapered protrusions may be
located, for instance, at a distance of 0 to 20mm from an external surface of the
radiation source, preferably 0 to 10mm, more preferably 2 to 5mm. The provision
tapered protrusions that extend from an internal wall of the catalyser device to a
position near to or touching the radiation source advantageously acts to provide a
meandering non-laminar flow-path of the fluid flowing through the reactor unit,
ensuring a thorough mixing of the fluid, and ensuring that all of the fluid flowing
through the reactor unit is contacted with the photocatalytic material and exposed
to UV radiation from the radiation source.
Preferably the tapered protrusions extend substantially perpendicularly from the
internal surface 21 of the wall portion towards the radiation source 30 positioned
centrally in the catalyser device, in order to avoid or minimise any areas of the
intemal surface of the catalytic material support that may be shaded from direct
exposure to UV radiation from the radiation source. Advantageously the tapered
protrusions extend substantially perpendicularly from the wall portion to a central
axis of the radiation source. In this way the surface area of the catalytic material
support exposed to direct ultraviolet radiation from the ultraviolet radiation source
may be maximised. Where the radiation source is in the form of a plurality of UV
radiation sources, e.g. a multi-tube ultraviolet lamp, the tapered protrusions
positioned around the internal surface of the catalyser device may point towards a
central axis where the radiation source is positioned.
Figure 3b shows a possible arrangement of the tapered protrusions 8 around the
circumference of the intemal surface of a catalyser device 4 according to an
embodiment of the present invention. In the embodiment illustrated the catalytic
support material 6 is configured to receive a double-tube UV lamp along a central
axis of the catalyser device. In Figure 3b the tips of the tapered protrusions 8 point
towards the central axis of the catalyser device which constitutes also the central
axis of the double-tube UV lamp radiation source when inserted in the catalyser
device. It is also envisaged that the tips of the tapered protrusions may point
towards the central axis of each of the UV tubes, i.e. as indicated by the numerals
32 in Figure 3b.
The tapered protrusions within one catalyser device may have different lengths, for
instance dependant on the form of the radiation source received in the catalyser
device.
Preferably the distance between the radiation source and the irradiated surface of
the internal wall portion of the catalytic support material is between 20mm to
70mm, preferably between 30mm to 55mm to optimise the overall effectiveness of
the photocatalytic activity on fluid passing therethrough.
The plurality of tapered protrusions may be arranged in a regular arrangement
around the internal surface of the catalyser device, for instance in a series of
regularly spaced rows. Preferably the tapered protnjsions may be arranged in
stepped rows around the internal surface of the catalytic material support, such that
the tapered protrusions in each row around the circumference of catalyser device
are not aligned with the tapered protrusions in the adjacent circumferential rows
along the direction of fluid flow through the reactor unit. In other words, tapered
protrusions at different positions along the fluid flow channel are arranged in an
angularly offset manner around the internal surface of the catalytic material
support. According to a preferred embodiment the tapered protrusions within a row
are equally spaced apart and the rows are equally spaced along the length of the
catalyser device. Preferably each row of tapered protrusions is displaced by a half
step relative to the adjacent row, whereby a step corresponds to the distance
between adjacent protrusions in a row. Such a stepped arrangement of the
tapered protrusions advantageously provides effective mixing of the fluid flowing
through the reactor unit.
Preferably the tapered protrusions 8 have a conical form, which advantageously
allows a relatively natural flow of the fluid through the reactor unit and accordingly
minimising the charge loss. The base portion 5 of tapered protrusions preferably
has a substantially circular shape for enabling easy manufacture of the tapered
protrusions. Other shapes for the base portion of the tapered protrusions may be
envisaged, such as, for instance circular, oval, hexagonal, octagonal, rhomboid or
triangular.
The tips of the tapered protrusion may have, for instance, a pointed, truncated or
rounded form. The tips of the tapered protrusions preferably have a small cross-
section area in order to minimise the surface area of the radiation source which is
obstructed by the tips of the protrusions, thus ensuring that a maximum amount of
the irradiation from the radiation source reaches the rest of the surface of the
catalytic material support.
The tapered protrusions may preferably have an average height h to average
maximum base diameter d ratio of 6:1 to 1:1, preferably of 4:1 to 2:1. The height of
a tapered protrusion is here measured form the radially innermost point of the tip to
the radially outermost point of the base portion. The largest base diameter is here
measured as the maximum distance measured across the cross section of the
base portion of the protrusion.
The tapered protrusions preferably have an internal taper angle a of 1 to 30°,
preferably 1 to 15°, for example 5 to 15°. Accordingly, the balance between the
number of protrusions within the catalyser device, providing a large surface area of
photocatalytic material, and the provision of a sufficient direct irradiation of the
surface of the catalyser support material by the UV radiation source may be
optimised.
As illustrated in figure 3c, it is possible to provide in addition certain other
protrusions 19 extending from the internal surface 21 of the wall portion to a tip 23
that is not proximate to the radiation source, such that the inner surface of the
catalytic device comprises both long and short protrusions in view of increasing
radiated catalyser surface area and to increase fluid flow contact with catalyser
surface area near the base of the protrusions.
At least a portion of the Internal surface of the catalytic material support is coated
with a photocatalytic material. Preferably substantially the whole of the internal
surface of the catalytic material support which is irradiated with ultraviolet light from
the ultraviolet radiation source is coated with photocatalytic material.
The photocatalytic material may be any known photocatalytic material. Preferably
the photocatalytic material comprises particles of inorganic semi-conductor,
particularly, cadmium sulphide, zinc sulphide and/or titanium dioxide in anatase
crystalline form. Preferably the photocatalytic material comprises titanium dioxide
in view of its effective catalytic activity in the presence of ultraviolet light, its
stability, and its harmlessness to the human organism.
In a particular embodiment of the present invention the photocatalytic material
comprises an inorganic binder including ultraviolet light permeable polymeric
molecules, a polar diluent, and particles of an inorganic semi-conductor, the weight
of the inorganic semi-conductor particles being two to twenty times less than the
weight of both the diluent and binder. The polymeric molecules preferably include
acrylic molecules. Advantageously a photocatalytic gel as described in WO
2007/060520 may be used. Such a photocatalytic gel material exhibits good
adhesion to many types of materials, and advantageously can be dried in air with
out the need for high temperature treatment, thus allowing the coating of materials
that do not support high temperatures such as plastics.
The photocatalytic material is applied onto an internal surface of the photocatalytic
support material in order to use its photocatalytic properties to treat gases, such as
clean and deodorize air. Advantageously the photocatalytic material may be in a
liquid or gel form for easy application to the catalytic support material. The
photocatalytic material may conveniently be applied to the catalytic material
support for instance by spraying or painting of the gel or liquid on to a surface of
the support, or by immerging the support into a receptacle containing the
photocatalytic material.
The catalytic material support may advantageously be formed from a plastics
material, e.g. polystyrene, polyvinyl chloride, acrylonitrile styrene, polyethylene,
polyethylene terephtalate, polymethyl methacrylate.. The tapered protrusions and
the wall portion of the catalytic material support may be manufactured separately,
for example by injection moulding or extrusion moulding, and bonded, welded,
glued or othenA/ise fixed together but preferably the tapered protrusions are formed
integrally with the wall portion.
Referring particularly to Figure 4a, according to a particular feature of the invention
the catalytic material support 6 may be constructed from a single sheet of flexible
material.
The tapered portions can be easily and economically integrally formed from a sheet
of flexible plastics material by thermoforming or moulding or by other standard
methods. The flexible plastics material may be for example polystyrene, polyvinyl
chloride, acrylonitrile styrene, polyethylene, polyethylene terephtalate or polymethyl
methacrylate.
The sheet of flexible material with the integrally formed tapered protrusions is then
bent into a tubular shape and may be welded, crimped, bonded or held together by
mechanical clamps along its seam to form a tube, or simply held in an outer
support tube without being held together along its seam. The sheet may be
provided with grooves or indents 9, as best seen in Fig. 4b, that ease the bending
of the sheet into a tubular shape, and improve the reproducibility of the tubular
shape.
It is preferred to form the catalytic device from a single sheet, however within the
scope of the invention, it is also possible to form the catalytic device from two or
more sheets welded, bonded or fixed along their edges to each other by
mechanical means (such as rivets or clamps). The two or more sheets could also
be assembled without being bonded together, in a tubular housing of the reactor
unit that positions and supports the sheets such that they collectively form a tube
around the radiation source.
The photocatalytic material may advantageously be applied to the catalytic material
support before the support is folded to form a tube. For instance the photocatalytic
material may be painted or sprayed onto the surface of the catalytic material
support sheet before folding of the support to form a tube. Advantageously the
photocatalytic material may be sprayed onto the catalytic material support sheet by
a mechanised spraying system, e.g. an automated spray system, making the
application of the photocatalytic material to the reactor unit very simple and
economic.
Where the catalytic support material is produced from a single sheet of flexible
material the tapered protrusions should be spaced sufficiently far apart to allow
bending of the sheet to form a tube. The spacing required will depend, amongst
other things on the diameter of the catalyser device and the relative size of the
protrusions.
Where the tapered protrusions are formed integrally from the sheet of flexible
material by a method such as thermoforming it is necessary that the base portion
protrusions encompass a sufficient amount of the plastics material to enable the
forming of the tapered protrusion. Preferably the protrusions have an average
height h to average maximum base diameter d ratio 4:1 to 2:1.
The catalytic support according to the invention can thus be made particularly
lightweight, while providing very efficient treatment due to the high actively radiated
surface and effective aerodynamics of the tapered protrusions. This
advantageously enables the reactor units according to the invention to be used in
mobile applications such as in aeroplanes or automobiles, or for use in mobile or
even portable fluid treatment apparatus.
The reactor unit may further comprise a radiation baffle in at least one of the fluid
inlet module 10 and fluid outlet module 20, in order to prevent the ultraviolet
radiation source from being visible outside the reactor unit.
In the embodiment illustrated in Figures 1 and 2, the fluid inlet module 10 and fluid
outlet module 20 include a radiation baffle 12 with multiple fluid-flow passages.
Referring to Figures 6a and 6b, the radiation baffle may advantageously comprise
multiple concentric S-shaped vanes 15.
The radiation baffle may be provided as a single unit. Alternatively the radiation
baffle may be manufactured as separate units which may then be mounted or
connected together in the fluid inlet and/or fluid outlet module. In the illustrated
embodiment the radiation baffle is comprised of two separate radiation baffle units
13 and 14 which may be manufactured simply and economically e.g. from a
plastics material by standard methods such as injection moulding.
The radiation baffle may conveniently be manufactured from a plastics material
such as polyethylene, polybutadiene terephtalate, acrylonitrile butadiene styrene,
polymethyl methacrylate, polyvinyl chloride, fibre-glass mineral or cellulosic type
polymers.
Advantageously the radiation baffle effectively minimises or eliminates the direct
emission of the ultraviolet light emitted by the radiation source outside the reactor
unit. Accordingly the reactor unit may be used in any environment without requiring
an additional cover or outer housing, making the reactor unit easy and convenient
to use.
In the illustrated embodiment the radiation baffle 12 in the fluid inlet module 10 also
acts as a filter to remove insects, large particles and dust. Alternatively, the reactor
unit may include a separate filter at its inlet.
In the embodiment illustrated in Figures 1 and 2, the fluid inlet module 10 and fluid
outlet module 20 comprise a metallic filter 18 to provide further improved fluid
purification.
The filter comprises one or more metal components having fluid purifying activity.
The metal may be a metal that has germicide activity, such as copper, silver or
zinc, or a reactive metal that has activity for converting noxious chemicals into
compounds harmless to the human organism, e.g. which can act to convert carbon
monoxide to carbon dioxide, such as gold, platinum, palladium, rhodium or
zirconium.
In the illustrated embodiment the fluid purification active metal is provided on a
separate filter component 18. It is also envisaged that the metal component may
be provided on the surface of a component of the reactor unit, for instance as a
coating, on the surface of the radiation baffle 12.
The filter may also be formed from metal wire for instance as a gauze or fibre-glass
type structure. According to a preferred embodiment the filter 18 may have an
open-cell foam type structure, e.g. with at least 70%, preferably more than 80%
space. Advantageously such a foam-type filter provides a large surface area of for
filter for contact with the fluid flowing through the reactor unit whilst minimising
charge loss. The filter may be formed from a plastics or metallic material, with the
one or more metal components having fluid purifying activity coated on the surface
thereof.
The metallic filter component advantageously provides further enhanced the fluid
purification properties of the reactor unit, e.g. with respect to certain pathogens
such bacteria, and with respect to removing certain noxious compounds such as
carbon monoxide.
The reactor unit of the present invention may easily and conveniently be used in
systems for air purification. Figures 8a to 8c show schematic illustrations of some
possible air purification systems 50, 60 using the reactor unit of the present
invention. The purification systems include a drive unit to which one or more
reactor units according to the present invention are removably connected. The
drive unit comprises an electrical connector for providing current to the radiation
source electrical connector 31, and a fluid flow system for propelling or drawing air
through the reactor unit. The drive unit may be configured for connection to the
mains electrical network or may, for instance, be battery powered.
For instance the drive unit may include a connection member 40 with socket
connectors 42 into which the electrical pin connectors of the radiation source 31
are received. Electrical connection may be effected by inserting the connection
member 40 into the fluid inlet 10 or fluid outlet module of the reactor unit.
Advantageously the removable connection between the reactor unit and the drive
unit is provided by a quarter-turn electrical connection, whereby the connection
member is inserted into tlie reactor unit and rotated to bring the electrical connector
in the socket connectors 42 into electrical contact with the radiation source
electrical pin connectors 31. The connection member or the reactor unit may
comprise complimentary locking means 44 to limit the rotation of the connection
member 40 with respect to the reactor unit and/or to hold the reactor unit and
connection member together.
The use of a quarter tum electrical connector on the reactor unit advantageously
allows simple and easy connection of the reactor units into a fluid purification
system.
Figure 8c shows an apparatus 60, designed for the cleaning and deodorising of
large volumes of air or other gases according to the present invention in which may
a plurality of the reactor units 1 are grouped together in a single housing 62.
The compact and modular nature of the reactor unit enables it to be easily
integrated into a fluid treatment apparatus 50 having a housing 51 receiving a
single reactor unit 1 or with a plurality of reactor units, depending on the volume of
fluid to be treated. The apparatus housing may comprise an air inlet grill 54 and
user interface screen or display 52 providing information on the usage of the
apparatus and maintenance requirements, such as need for replacement of the
reactor unit, radiation source and/or catalytic device.
The reactor units may advantageously be used in an apparatus for the purification
treatment of air (cleaning, sterilising and deodorising) in households, offices,
factories, and hospitals. The particularly compact arrangement and efficient and
effective operation of the reactor unit also enables it to be advantageously used in
aircraft and automobiles for cleaning, sterilising and deodorising air. The reactor
unit may also be used for the photocatalytic treatment of many other gases or
mixture of gases for various applications. For instance, the reactor unit may be
used for purifying gases such as nitrogen or carbon dioxide used in the food and
beverages industry for food preservation, deodorising gaseous effluents or treat
ultra-pure air in electronic or pharmaceutical clean rooms.
Claims
1. A reactor unit for photocatalytic treatment of fluids including a housing, a
catalyser device comprising a catalytic material support having a generally tubular
shape defining a fluid flow channel extending around and along a fluid flow path
and a photocatalytic material coated on at least a portion of an internal surface of
the support, and a radiation source received in a central portion of the catalyser
device, wherein the catalytic material support comprises a wall portion and a
plurality of tapered protrusions extending from an internal surface of the wall
portion to a tip positioned at a distance to the radiation source within a range of 0 to
50% the distance separating the radiation source and the internal surface of the
wall portion, the tapered protrusions being arranged around the radiation source
and along the fluid flow channel.
2. A reactor unit according to claim 1 wherein the tips of the tapered
protrusions are within a range of 0 to 30% the distance separating the radiation
source and the internal surface of the wall portion.
3. A reactor unit according to claim 1 or 2 wherein the tapered protrusions
extend substantially perpendicularly from the internal surface of the catalytic
material support wall portion towards a central axis of the radiation source.
4. A reactor unit according to claim 1, 2 or 3 wherein the tapered protrusions
have an average height to average base diameter ratio in a range from 6:1 to 1:1.
5. A reactor unit according to any one of claims 1 to 4 wherein the tapered
protrusions have a generally conical form.
6. A reactor unit according to any one of the preceding claims wherein tapered
protrusions at different positions along the fluid flow channel are arranged in an
angularly offset manner around the internal surface of the catalytic material
support.
7. A reactor unit according to any one of the preceding clainns wherein the
catalytic material support is formed from a sheet of flexible material folded to form a
tubular shape, and the tapered protrusions are formed integrally from the sheet of
flexible material.
8. A reactor unit according to claim 7 wherein the catalytic material support is
formed from a plastics material.
9. A reactor unit according to claim 7 or 8 wherein the tapered protrusions are
formed by moulding, extrusion orthermoforming of the sheet of flexible material.
10. A reactor unit according to any one of the preceding claims wherein the
radiation source is in the form of one or more UV light tubes.
11. A reactor unit according to any one of the preceding claims wherein the
housing comprises a generally tubular body with a cavity for receiving the catalyser
device.
12. A reactor unit according to any one of the preceding claims further
comprising a fluid inlet module, a fluid outlet module and a filter comprising one or
more active metal components mounted in at least one of the fluid inlet and fluid
outlet modules.
13. A reactor unit for photocatalytic treatment of fluids including a catalyser
device comprising a catalytic material support having a generally tubular shape
forming a fluid conduit and a photocatalytic material coated on at least a portion of
an internal surface of the support, a radiation source received in a central portion
of the catalyser device, a fluid inlet module, a fluid outlet module and a filter
comprising one or more active metal components mounted in at least one of the
fluid inlet and fluid outlet modules.
14. A reactor unit according to claim 13 wherein the filter is in the form of a
plastic foam having an open pore structure coated with an active metal.
15. A reactor unit according to claim 13 or 14 wherein the active metal is
selected from the group comprising silver, copper, gold, platinum, zinc, palladium,
rhodium or zirconium.
16. A reactor unit for photocatalytic treatment of fluids including a catalyser
device comprising a catalytic material support having a generally tubular shape
forming an fluid conduit and a photocatalytic material coated on at least a portion of
an internal surface of the support, a radiation source received in a central portion
of the catalyser device, a fluid inlet module and a fluid outlet module, wherein at
least one of the fluid inlet module and fluid outlet module comprises and a radiation
baffle having multiple fluid-flow passages.
17. A reactor unit according to claim 16 wherein the fluid-flow passages of the
radiation baffle are formed by multiple concentric S-shaped vanes running from an
axially interior surface to an exterior surface of at least one of the inlet and outlet
modules.
18. A reactor unit according to any one of claims 13 to 17, wherein the catalytic
material support comprises a wall portion and a plurality of tapered protrusions
extending substantially perpendicularly from a base on an interior surface of the
wall portion to a tip proximate to the radiation source.
19. A reactor unit according to claim 18 further comprising any one or more of the
additional features of the reactor unit according to any one of claims 1 to 11.
20. A catalyser device comprising a catalytic material support and a
photocatalytic material coated on at least a portion of a side of the support, the
support comprising a single sheet of a flexible material folded to form a generally
tubular shape or a portion of a generally tubular shape and plurality of tapered
protrusions extending from one face of the sheet of flexible material and formed
integrally from the sheet of flexible material.
21. A catalyser device according to claim 20 wherein the catalytic material
support is formed from a plastics material.
22. A catalyser device according to any of claims 20 or 21 wherein the tapered
protrusions are formed by moulding or thermoforming of the sheet of flexible
material.
23. An apparatus for photocatalytic treatment of fluid, such as for cleaning and
deodorising air, comprising a reactor unit according to any one of claims 1 to 19
and a drive unit to which the reactor unit is removably connected, said drive unit
comprising a power source for providing electrical power to the radiation source,
and a fluid flow system for propelling or drawing fluid through the reactor unit.
24. An apparatus for photocatalytic treatment of fluid according to claim 23
wherein the removable connection between the reactor unit and the drive unit is
provided by complimentary quarter-turn electrical connector.
25. An apparatus for photocatalytic treatment of fluid according to claim 23 or
24 comprising a plurality of drive units mounted on a common support and a
corresponding plurality of reactor units coupled to respective drive units.
26. A method of making a catalyser device comprising moulding or thermoforming
a plurality of tapered protrusions out of a sheet of polymeric material, coating at
least a portion of a side of the sheet with a photocatalytic material, and forming a
generally tubular shape from one or more said sheets of polymeric material.
27. The method of claim 26 wherein the photocatalytic material is applied to the
sheet of polymeric material before the support is folded to form a tube.
28. The method of claim 27 wherein the photocatalytic material is sprayed by an
automated spray system onto the surface of the sheet.

A reactor unit tor photocalalytic
treatment of fluids such as air. includes a catalyse:
device (4) comprising a catalytic material support
having a generally tubular shape defining a fluid
flow channel extending around and along a fluid
flow path and a photocatalytic material coated
on at least a portion of an internal surface of the
support, and a radiation source (30) received in a
central portion of the eatalyser device. The catalytic
material support comprises a wall portion and
a plurality of tapered protrusions (8) extending
from an internal surface of the wall portion to a
tip proximate to the radiation source, the tapered
protrusions being arranged around the radiation
source and alone the fluid flow channel.

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http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=H+eOVVHqOpNie2WFBk2HKQ==&loc=wDBSZCsAt7zoiVrqcFJsRw==

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Patent Number

277130

Indian Patent Application Number

1198/KOLNP/2010

PG Journal Number

47/2016

Publication Date

11-Nov-2016

Grant Date

11-Nov-2016

Date of Filing

05-Apr-2010

Name of Patentee

AELORVE S.A.S.

Applicant Address

27/29 RUE RAFFET, F-75016 PARIS FRANCE

Inventors:

#	Inventor's Name	Inventor's Address
1	PASTOR, JEAN-PIERRE	APPT 31A EDIFICIO PLAZA ALAMEDA, CALLE 2, LA ALAMEDA, CARACAS VENEZUALA

PCT International Classification Number

A61L 9/20

PCT International Application Number

PCT/IB2008/053984

PCT International Filing date

2008-09-30

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	07019639.9	2007-10-08	EUROPEAN UNION