System for purifying air in closed storage / transport space

Abstract

The invention relates to a system for purifying air in a closed storage / transport space, comprising an air purifier (10), the air purifier (10) comprising:-a housing having an air inlet (11) and an air outlet (12), in which an air flow channel is located in the housing between the air inlet (11) and the air outlet (12),-a fan (22), the invention relates to an air purifier (10) comprising:-an air inlet (11) configured to draw air from a storage / transport space into a flow channel in the air purifier (10) via an air inlet (11) and blow purified air back into the storage / transport space via an air outlet (12),-a filtration system arranged in the flow channel in such a way that the air flows through the filtration system, the filtration system comprises, as chemical filtration materials, both an ultraviolet-activated photocatalyst and a chemical filtration material comprising potassium permanganate, and-an ultraviolet-emitting light source (23) for activating the photocatalyst of the filtration system. The filtration system comprises a main filter (26) forming a cartridge comprising at least two batten bins, where the filter material contained in a first batten bin comprises potassium permanganate, the second batten bin comprises a selected chemical filter material, and air is passed through the batten bins.

Description

Technical Field

[0001] The present invention relates to a system for purifying air in a closed storage / transportation space, the system comprising an air purifier, the air purifier comprising

[0002] a housing having an air inlet and an air outlet, wherein the air flow channel is located within the housing between the air inlet and the air outlet,

[0003] a fan configured to draw air from the storage / transport space into the flow channel within the air purifier via the air inlet and to blow the purified air back into the storage / transport space via the air outlet,

[0004] a filter system arranged in the flow channel in such a way that the air flows through the filter system, wherein the filter system comprises both an ultraviolet-activated photocatalyst and a chemical filter material comprising potassium permanganate as chemical filter material, and

[0005] - UV emitting light source for activating the photocatalyst of the filtration system. Background Art

[0006] The land and sea transportation of fresh fruits, vegetables, berries, flowers and other plants from the place of production to the point of sale may take several days or even weeks, during which time the plants are in a closed refrigerated space. In addition, plants are stored for a long time in stores and wholesale warehouses before being sold. As part of their natural life functions, plants produce ethylene (C2H4), which especially causes rapid ripening of fruits, aging of leaves of plants and withering of flowers and changes in the taste of vegetables. In particular, green plants are very sensitive to the adverse effects of ethylene, such as yellowing. Ethylene is especially produced in large quantities in ripe fruits and aging, rotten and moldy tissues. For example, bananas, apples, kiwis and tomatoes produce large amounts of ethylene.

[0007] In addition to ethylene, the air in the shipping / storage space may contain harmful bacteria such as Salmonella, Listeria and E. coli, Bacillus cereus, as well as viruses and molds, which should be removed from the shipping / storage space.

[0008] Transporting and storing plants in closed spaces can cause ethylene to accumulate in the space where the plants are kept, and ethylene concentrations can become quite high. Excessive ethylene concentrations in closed storage or transport spaces can cause severe plant decay.

[0009] It is known to use air purifiers in storage spaces in order to keep ethylene concentrations low and remove other harmful substances. A suitable air purification device for eliminating ethylene is known from patent publication US 2013 / 0202494 A1, in which an air purification device based on photocatalytic oxidation is disclosed.

[0010] When ultraviolet radiation with a wavelength less than 400 nm is directed at the surface of a selected semiconductor (e.g., titanium dioxide (TiO2) or zinc oxide (ZnO)), the energy of the photons excites electrons from the valence band to the conduction band. As a result, the short carbon chain of ethylene is very easily broken in a spontaneous chemical reaction at or very close to the semiconductor surface. The end products of the reaction are carbon dioxide and water.

[0011] However, the use of photocatalysts alone is not particularly effective for removing ethylene. In addition to photocatalysts, it is known to use potassium permanganate to eliminate ethylene. Patent publication US2014342064A1 discloses the use of potassium permanganate and titanium dioxide to remove ethylene from the vegetable compartment of a refrigerator. The combination of photocatalyst and potassium permanganate is very effective in purifying the air, especially in spaces where food is stored, because viruses, bacteria and molds in the air can be effectively removed with the help of photocatalysts (especially titanium dioxide), while potassium permanganate effectively removes ethylene.

[0012] A problem with known systems for purifying the air in closed storage / transport spaces is the handling and dimensioning of the filter material to meet the needs of different storage / transport spaces. Summary of the invention

[0013] The object of the present invention is to provide an improved system for purifying the air of a storage / transport space of ethylene and other impurities which reduces plant decay in the space concerned. The characteristics of the invention are pointed out in the attached patent claim 1.

[0014] The system for purifying air in a closed storage / transport space according to the present invention comprises an air purifier, the air purifier comprising: a housing having an air inlet and an air outlet, wherein an air flow channel is located within the housing between the air inlet and the air outlet; a fan configured to draw air from the storage / transport space into the flow channel within the air purifier via the air inlet, and to blow the purified air back into the storage / transport space via the air outlet; a filter system arranged in the flow channel in such a way that air flows through the filter system, wherein the filter system comprises both an ultraviolet-activated photocatalyst and a chemical filter material comprising potassium permanganate as chemical filter materials, and comprises an ultraviolet-emitting light source for activating the photocatalyst of the filter system. The filter system comprises a main filter, the main filter forming a cassette comprising at least two crates, wherein a first crate contains potassium permanganate and a second crate contains a selected chemical filter material, and wherein air is caused to flow through the crates.

[0015] The system according to the invention is designed to remove ethylene from the air, in particular ethylene produced by plants present in the space. In addition, the system effectively eliminates bacteria, viruses, molds and VOC gases from the air. By combining multiple chemical filter materials in the air purifier, different air pollutants can be eliminated very effectively. By combining potassium permanganate and ultraviolet-activated photocatalysts in the same air purifier, the ethylene removal rate is significantly improved, even multiplied, compared to the use of photocatalysts alone. Potassium permanganate, especially when used with ultraviolet-activated titanium dioxide, is very effective in degrading ethylene in the air. Accommodating potassium permanganate in crates makes it possible to use potassium permanganate combined with particles made of, for example, aluminum oxide as a filter material. The fact that the main filter of the filtration system includes a crate in which the selected filter material is accommodated makes the handling of the filter material easier and the size of the filtration system can be easily determined according to the requirements of the storage / transport space and the products to be handled in the space. By using at least two crates in the main filter, at least two different filter materials can be adopted in the main filter, or only the amount of potassium permanganate can be easily adjusted.

[0016] The main filter is thus designed as a cassette structure comprising removable crates, so that the air purifier can be easily adapted to the requirements of use and different amounts of filter material and filter material comprising different active substances can be used depending on the space. With the aid of the crates of the main filter, solid filter material, in particular filter media, can be used in the main filter. The system has at least two crates in series, through which the air flows, achieving a multiplying effect, so that pollutants in the air can be eliminated more effectively than in previous systems.

[0017] Advantageously, the system also includes an ethylene sensor that measures the ethylene concentration in the air of the storage / transport space. By continuously monitoring the ethylene concentration, the storage / transport space can be ventilated as needed, or the removal of ethylene can be increased if the ethylene concentration becomes too high and poses a potential risk to the stored product.

[0018] Advantageously, the system further comprises data transmission means for transmitting the measurement data generated by the ethylene sensor to the server and recording means for recording the measurement data. Thus, log data of the conditions in the storage / transport space over a selected period of time can be formed.

[0019] It is also possible to measure, transmit and record the levels of humidity, temperature, carbon dioxide, VOC and fine particulate matter (e.g. PM2.5 and PM10) in the storage / transport space with the aid of appropriate sensors. Thus, the conditions in the storage / transport space can be monitored in more detail to maintain optimal conditions.

[0020] Advantageously, the main filter also comprises at least one fabric filter, which advantageously comprises a selected chemical filter material. This allows to improve the performance of the filtration system and / or to use filter materials in the fabric filter that are impossible or unsuitable to place in the crate. With the fabric filter, it is possible to use filtering nonwovens in the main filter. The fabric filter can also filter the filter material contained in the crate to prevent the filter material from ending up outside the air purifier, thereby preventing the filter material, which could be harmful to humans or products in the space, from ending up in unwanted places.

[0021] Advantageously, the crates can be removed from the box. This allows easy replacement of the crates and / or the filter material contained in the crates in the main filter.

[0022] Advantageously, the main filter comprises 2-8 crates, advantageously 4-6 crates. Thus, it is easy to provide the desired amount of selected filter material in the main filter.

[0023] Advantageously, the main filter of the air purifier comprises at least one crate, the filter material contained in the at least one crate comprises a UV-activated photocatalyst, advantageously a glass tube coated with titanium dioxide. Thus, the main filter effectively purifies the air of ethylene and other organic substances, bacteria, viruses, mold and VOC gases.

[0024] The main filter of the air purifier can have a cover made of highly light-transmitting plastic, advantageously made of polymethyl methacrylate, advantageously with a thickness of 2-4 mm, more advantageously with a thickness of 2-3 mm. Thus, the photocatalytic filter material contained in the main filter can be activated by means of a light source outside the main filter. This allows the light source to be arranged in a fixed manner inside the air purifier and the main filter to be replaced without removing the light source.

[0025] The main filter of the air purifier may comprise a fabric filter comprising activated carbon and the fabric filter is advantageously the last filter in the filter system in the direction of air flow. This enables gases and unpleasant odors to be removed from the air. Furthermore, the activated carbon filter arranged last in the direction of flow ensures that potassium permanganate and other chemical filter materials cannot be transported to the outside of the air purifier via the air outlet.

[0026] Advantageously, the UV-activated photocatalyst of the air purifier is titanium dioxide, copper oxide or zinc oxide. These photocatalysts have been shown to be effective in purifying air in storage / transport spaces.

[0027] Advantageously, the filtration system of the air purifier also includes activated carbon and / or nanosilver as filter material. This enables a variety of different pollutants to be effectively removed from the air in addition to ethylene.

[0028] The air purifier may also include a HEPA filter for removing airborne particles from the storage / transport space.

[0029] Advantageously, the UV emitting light source of the air purifier is a short wave UV emitting LED having a wavelength advantageously of 255-275 nm. Using LED as a light source allows the same light source to last throughout the life of the air purifier and makes the air purifier very energy efficient. At this wavelength, the photocatalytic properties, in particular the photocatalytic properties of titanium dioxide, are significantly enhanced.

[0030] Advantageously, the air purifier comprises an auxiliary light source, which is advantageously a blue emitting LED. Thus, the blue LED generates visible light which can be used as an indicator to the user that the air purifier is operating. To this end, the auxiliary light source can be connected to the same circuit as the above-mentioned light source. Furthermore, the blue LED acts as an additional catalyst for the photocatalytic filter material, thereby making the operation of the filter system more efficient.

[0031] Advantageously, the main filter of the air purifier is fixed in the flow channel by means of fixing means in such a way that the main filter can be removed without tools. The filter material contained in the main filter is susceptible to wear during use, so that its effectiveness decreases. In the case where the system is to be used continuously, the filter material must be replaced regularly. It is also desirable to change the amount and / or quality of the filter material contained in the crate as required, so that the main filter may need to be removed frequently. In this case, these actions can be carried out quickly and easily, since the main filter is fixed in the air purifier in such a way that its removal does not require tools. This makes maintenance of the air purifier very easy. Advantageously, the main filter of the air purifier can be replaced in less than one minute without the need for tools.

[0032] Advantageously, the main filter of the air purifier is arranged in the housing by means of a slide rail in such a way that the main filter can be removed without opening the housing. This makes it easy to remove and replace the main filter, since the housing of the air purifier does not need to be opened in order to remove the main filter. In different embodiments of the invention, other known fixing solutions (such as, for example, different screws, clamps, magnets or snap-fit ​​mechanisms, etc.) may be used instead of the slide rail.

[0033] In an embodiment of the present invention, the housing of the air purifier can also be closed by means of a quick-release fastener, so that the housing can be easily opened without tools, and the main filter can be replaced by opening the housing.

[0034] Advantageously, the filtration system of the air purifier further comprises a pre-filter arranged in the flow channel, wherein the pre-filter comprises a non-woven fabric comprising a selected chemical filter material. This allows improving the overall performance of the air purifier.

[0035] Advantageously, the pre-filter is arranged in the air flow channel upstream of the main filter in the direction of air flow. This allows improving the overall performance of the air purifier.

[0036] The nonwoven fabric of the pre-filter of the air purifier may include an ultraviolet-activated photocatalyst (advantageously titanium dioxide), and the ultraviolet-emitting light source may be directed toward the pre-filter. Thus, the air drawn into the flow channel can be effectively pre-filtered before being directed to the main filter, thereby improving the overall air purification performance of the system. This also makes it easy to direct the light source toward the photocatalyst to activate the photocatalyst. Thus, the pre-filter effectively purifies the air of ethylene and other organic matter, bacteria, viruses, mold, and VOC gases. The nonwoven fabric of the pre-filter may also include nanosilver. In addition to the nonwoven fabric, alternative materials (e.g., alumina or glass) may also be used as structural materials in the pre-filter.

[0037] Advantageously, the pre-filter of the air purifier is fixed in the flow channel by a fixing device in such a way that the pre-filter can be removed without tools. This makes it easy and quick to remove and replace the pre-filter during system maintenance, thereby reducing maintenance costs.

[0038] Advantageously, the pre-filter of the air purifier is arranged in the housing by means of slide rails, so that the pre-filter can be removed without opening the housing. This makes it easy to remove and replace the pre-filter. Alternatively, the above-mentioned and per se known method for fixing the main filter can be used for the pre-filter.

[0039] Advantageously, the air cleaner further comprises a coarse filter which prevents macroscopic particles from entering the air flow path.

[0040] The system advantageously comprises software means configured to trigger an alarm if the ethylene concentration exceeds a predefined threshold. Thus, an increase in ethylene concentration exceeding the threshold is quickly known, enabling immediate initiation of the required measures to prevent product deterioration in the storage or transport space.

[0041] Advantageously, the system comprises software means for reading the real-time ethylene concentration and the parameters describing the operation of the air purifier and adding to the measured data. This enables continuous monitoring of the air conditions in the storage or transport space. Thus, the user is also constantly informed of the operation of the air purifier.

[0042] The system is advantageously configured to measure and record the ethylene concentration in a database at intervals of 1 second to 10 minutes, advantageously at intervals of 10 seconds to 2 minutes. Thus, changes in ethylene concentration are captured with sufficient accuracy.

[0043] Advantageously, the storage / transport space comprises an air circulation refrigerator, the air purifier is arranged on the ceiling of the storage / transport space close to the refrigerator, and the refrigerator of the storage or transport space is configured to supply power to the air purifier. Thus, the device does not take up space for the product to be stored or transported, and the air purifier does not require a separate power supply, but can draw its operating power from the refrigerator. The air purifier in the storage space can also be connected to the power grid.

[0044] The nominal volume of the storage / transport space is advantageously 5-500 cubic meters, most advantageously 50-250 cubic meters. In this range, the air purifier is suitable for purifying the air in the storage / transport space in terms of its performance. However, the crate structure of the main filter allows the system according to the invention to be well extended to spaces of different sizes and different applications, since the active agent of the filter material and its amount can be easily adjusted.

[0045] Advantageously, the effective air volume of the storage or transport space is 5-60%, advantageously 8-30%, of the nominal purification capacity of the air purifier. Thus, surprisingly large transport / storage spaces can be purified using low-power air purifiers. If the cargo present in the space accounts for a considerable part of the total volume, the effective air volume may be much smaller than the nominal volume.

[0046] The nominal air flow rate of the air purifier fan can be 100-300m 3 / h. This allows the air flow rate through the air purifier to reach the required level in order to effectively purify the air in the closed storage / transport space. Here, the effectiveness of the air purifier in terms of flow rate means that the air must flow through the air purifier slowly enough to allow the pollutants to have sufficient time to react with the chemical filter material to eliminate the pollutants, but quickly enough to allow the entire effective air volume of the storage or transport space to be treated in a sufficient time interval. Advantageously, the flow rate of the air purifier is adjusted according to the effective air volume of the available space, the plants in the space and the filter material used.

[0047] Advantageously, the system includes software means for adjusting the fan power and / or starting the fan when the ethylene concentration measured by the ethylene sensor exceeds a predetermined threshold. Thus, the rate of air flow in the flow channel of the air purifier can be adjusted according to the existing conditions. For example, when the air purification demand is low, the fan can be kept at a low power to reduce energy consumption and noise, and the power can be automatically increased as needed. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The present invention will be described in detail below with reference to the accompanying drawings which show embodiments of the present invention, in which:

[0049] Figure 1a shows an axonometric projection of a front exterior view of an air purifier according to the invention,

[0050] Figure 1b shows an axonometric projection of a rear external view of an air purifier according to the invention,

[0051] Figure 2 shows an opened air purifier according to the present invention,

[0052] Figure 3a The pre-filter of the air purifier according to the present invention is shown.

[0053] Figure 3b An opened pre-filter of an air purifier according to the present invention is shown,

[0054] Figure 4a The main filter of the air purifier according to the present invention is shown.

[0055] Figure 4b shows an opened main filter of an air purifier according to the present invention,

[0056] Figure 5 Schematically shows the system according to the invention in a transport space,

[0057] Figure 6 Measured data relating to the effect of the system according to the invention on the ethylene concentration in an enclosed space are shown. DETAILED DESCRIPTION

[0058] Figure 1a and Figure 1b An external view of an air purifier 10 according to the present invention is shown. Figure 2 The air purifier 10 is shown opened so that the components inside the housing are visible. The housing of the air purifier 10 is composed of a base plate 13 and a cover plate 14, to which other components of the air purifier 10 are attached, and when the housing is closed, an air flow channel is formed between the base plate 13 and the cover plate 14.

[0059] In the external view of the air purifier 10, the air inlet 11 and the air outlet 12 can be seen. In the present embodiment, the air inlet 11 and the air outlet 12 are each composed of a plurality of separate openings. Located within the housing between the air inlet 11 and the air outlet 12 is an air flow channel containing a filtering system. The flow channel includes a fan 22, which is configured to draw air into the flow channel within the air purifier 10 via the air inlet 11. A coarse filter 16 is arranged in the air inlet 11, wherein all air entering the flow channel first flows through the coarse filter 16. The coarse filter 16 prevents macroscopic particles from entering the air filter 10. After the coarse filter 16, the air passes through a pre-filter 24 in the flow channel. The structure of the pre-filter 24 will be described later ( Figure 3a and Figure 3b ) is explained in more detail in the following. The pre-filter 24 is arranged above the fan 22 and is the same size as the fan 22 in terms of its surface area, so that all the air flowing in the flow channel passes through the pre-filter 24. Therefore, the fan 22 is downstream of the pre-filter 24 in the flow channel, between the pre-filter 24 and the main filter 26. The air from the fan 22 flows through the air guide 25 to the main filter 26, the structure of which will also be described later ( Figure 4a and Figure 4b The rear wall of the main filter 26 forms the air outlet 12 of the air purifier 10, through which the purified air that has also passed through the main filter 26 leaves the air purifier 10.

[0060] Both the pre-filter 24 and the main filter 26 are arranged in the air purifier 10 by means of a slide rail 30. More specifically, the bottom plate 13 of the air purifier 10 is designed to include a first slide rail 30, in which the main filter 26 is arranged, in such a way that the pre-filter 24 is pushed through the side wall of the air purifier 10 into the air purifier 10. On the other hand, the pre-filter 24 is designed in this embodiment to slide through the opposite side wall of the air filter 10 above the fan 22. The opening for the pre-filter 24 in the cover plate 14 is configured in such a way that, when the pre-filter 24 is in the air purifier 10, the upper part 241 of the pre-filter 24 is against the cover plate 14. Therefore, the pre-filter 24 is tightly pressed against the fan 22. The inner edge of the lower part 242 of the pre-filter 24 is located outside the edge of the fan 22, which prevents the lateral movement of the pre-filter 24. The edges of both the pre-filter 24 and the main filter 26 remain in the plane of the wall of the air purifier 10 or advantageously just outside it, whereby it is easy to grasp the filters from the outside of the air purifier and both filters can be pulled out of the air purifier 10 without tools and replaced with new ones very quickly. This can be done without opening the housing of the air purifier 10, i.e. without separating the cover plate 14 from the base plate 13. Figure 2 , the pre-filter 24 and the main filter 26 are partially pulled out of the housing of the air purifier 10 on the slide 30 to illustrate the mechanical movement of the pre-filter 24 and the main filter 26 during installation and removal. The end of the slide 30 advantageously includes a small buckle that locks the main filter 26 and / or the pre-filter 24 in place within the housing.

[0061] In this embodiment, the system according to the present invention also includes an ethylene sensor 18 for measuring ethylene concentration. In this embodiment, the ethylene sensor 18 is arranged on the side wall of the air purifier 10 in such a way that the ethylene sensor measures the ethylene concentration of the air outside the air purifier 10. Alternatively, the ethylene sensor 18 can be arranged inside the air purifier 10, close to the air inlet 11 in the air flow channel, upstream of the pre-filter 24 in the air flow direction. As far as its arrangement is concerned, it is necessary that the ethylene sensor 18 is arranged to measure the actual ethylene concentration of the air in the space, rather than the ethylene concentration of the air flowing out of the air purifier 10. More specifically, in this case ( Figure 1a ), only the active measuring end of the ethylene sensor 18 is outside the housing of the air purifier 10, and the rest of the measuring electronics are housed inside the housing of the air purifier 10. Alternatively, the ethylene sensor 18 and its equipment can also be arranged outside the air purifier 10 in the form of a separate unit. In this case, it is protected by the housing and can draw power from inside the air purifier 10.

[0062] The ethylene sensor 18 may be, for example, a Membrapor C2H4 / M-200 model, which can measure ethylene concentrations in the range of 0-200 ppm with a resolution of 1 ppm. An example of circuit connections for the ethylene sensor 18 may be found in the following publications

[0063] -Membrapor, "Specification Sheet for Ethylene Sensor Type C2H4 / M-200",

[0064] -Membrapor, "4 to 20mA Transmitter Board for Electrochemical GasSensorSuitable for Compact-Sensors(Pin layout:7-Series)"

[0065] 7 series))”

[0066] -CO2Meter Ltd., "EC200 Electrochemical Sensor Controller Manual", and

[0067] - NAZaidi et al., “A Gas Chromatographic System for the Detection of Ethylene Gas Using Ambient Air as a Carrier Gas”, Sensors 2017, 17, 2283.

[0068] The ethylene sensor 18 is connected to a data transmission device 20, which includes a router and an antenna 202. The ethylene concentration can be measured, for example, at intervals of 30 seconds, and the measurement data is transmitted by the data transmission device 20 to a server via a mobile phone network. This makes it possible to monitor the ethylene concentration of a space in real time via a remote connection and to record historical data of the ethylene concentration over long time intervals. In addition to the ethylene concentration, parameters describing the operation of the air purifier 10 can also be sent to the server via the data transmission device 20 together with the measurement data, wherein the parameters convey the status of the air purifier to the user.

[0069] In this embodiment, two antennas 202 are arranged on the air purifier 10, one antenna works on a GSM network suitable for long-distance data transmission, and the other antenna works on a WLAN network suitable for local data transmission.

[0070] In this embodiment, the ultraviolet-activated photocatalyst is arranged in the pre-filter, and the ultraviolet-emitting light source 23 for the ultraviolet-activated photocatalyst is arranged on the cover plate 14 of the air filter 10. More specifically, the light source 23 is composed of a short-wave ultraviolet-emitting LED, and in this embodiment, it is composed of three short-wave ultraviolet-emitting LEDs, and the peak intensity of the radiation emitted is 270nm. In another embodiment, two 275nm short-wave ultraviolet LEDs are used as the light source, and the current is 100mA.

[0071] In addition, the air purifier 10 in this embodiment also includes an auxiliary light source 231, which is a blue LED. The blue LED is connected to the same circuit as the short-wave ultraviolet LED that does not produce visible light. Therefore, the blue LED is used as an indicator to indicate to the user that the air purifier 10 is running. In addition, the blue LED acts as an auxiliary catalyst for the photocatalytic filter material, which improves the performance of the filter.

[0072] Depending on the application, the air purifier 10 can be configured to use the power grid or a selected lower voltage as its power source. In the present embodiment, the air purifier 10 uses power from the power grid, so the air purifier 10 includes a first transformer 31, by means of which the voltage is adapted to the fan 22 using a 24V voltage. The air purifier 10 also includes a second transformer 32, by means of which the voltage is adapted to the light source 23 using a 12V voltage and a measuring device including an ethylene sensor 18 and a data transmission device 20.

[0073] In this embodiment, the fan 22 has a power of 20W and a nominal air volume of 209m 3 / h radial fan model RG160-28 / 14N.

[0074] Figure 3a and Figure 3bThe pre-filter 24 of the air purifier 10 according to the present invention is shown, and the pre-filter 24 is composed of a plastic frame, and the non-woven fabric is arranged in the plastic frame. More specifically, the pre-filter 24 here includes an upper part 241 and a lower part 242, and the non-woven fabric is inserted between the upper part 241 and the lower part 242 (not shown in the figure). The flow channel of the air purifier 10 passes through the pre-filter 24, the opening 244 in the pre-filter, and thus passes through the non-woven fabric arranged in the pre-filter 24. Here, the pre-filter 24 includes a protrusion 246, and the pre-filter 24 is supported on the top of the fan 22 by means of the protrusion 246, and the edge of the fan 22 forms a slide rail 30. In addition, the pre-filter 24 shown in Figure 3 has a grip 248, and when the pre-filter 24 is inserted into the air purifier 10, the grip 248 remains outside the air purifier 10. Therefore, the user can grasp the grip portion 248 and pull the pre-filter out of the air purifier 10 through the grip portion 248 to replace the pre-filter 24. Air flows through the pre-filter 24 in the air purifier 10 along the direction indicated by arrow A.

[0075] In the present embodiment, the nonwoven fabric of the pre-filter 24 is treated by being immersed in a solution containing titanium dioxide, nanosilver and water. Titanium dioxide and nanosilver are retained in the dry nonwoven fabric, and together cause any inorganic substance to be oxidized into water and carbon dioxide in the air without producing ozone. The oxidation reaction can be accelerated by ultraviolet radiation. Therefore, the short-wave ultraviolet LED acting as the light source 23 and the blue LED acting as the auxiliary light source 231 are aligned with the pre-filter. Through the pre-filter 24, bacteria, viruses, molds and some VOC gases can be eliminated from the air.

[0076] Instead of or in addition to titanium dioxide, copper oxide or zinc oxide can also be used, which are also photocatalysts.

[0077] Figure 4a and Figure 4b The main filter 26 is shown without a cover 266. The main filter 26 forms a box in which a selected amount of a selected chemical filter material can be placed in a crate 261 or a fabric filter 262. The inner wall of the box structure of the main filter 26 includes a wide groove 264 and a narrow groove 263, and the crate 261 can be fixed in the wide groove 264, and the fabric filter 262 can be fixed in the narrow groove 263. In this embodiment, a maximum of four crates 261 and five fabric filters 262 can be arranged in the main filter 26. The fabric filter 262 can be placed before and after the crate 261 and between the crates 261. It is also possible to leave the positions for the crates 261 and the fabric filters 262 idle according to the application requirements. For example, in Figure 4a and Figure 4bIn the air purifier 10, the last position for the fabric filter 262 along the air flow direction is empty, and the position for the fabric filter 262 between the crates 261 is also empty. Inside the air purifier 10, the air flows through the main filter 26, the opening 268 on the opposite side wall of the main filter 26 in the direction indicated by the arrow B, and passes through all the crates 261 and the fabric filter 262 located in the main filter 26 in sequence. The crates 261 and the fabric filter 262 also have openings, and the air flow passes through these openings, and therefore also passes through the chemical filter material contained in the crates 261 and the fabric filter 262. The fabric filter 262 is formed in the same way as the pre-filter 24, that is, the non-woven fabric containing the active chemical filter material is arranged to be inserted between two parts forming a plastic frame. In terms of its structure, the chemical filter material contained in the crates 261 can be in any solid form (e.g., particles), and the active agent can be bonded to a selected structural material. Here, the position of the fabric filter 262 is the first and last in the airflow direction, so the crates 261 are positioned between the fabric filters 262, and between the crates 261. The crates 261 and the fabric filters 262 can also be positioned differently relative to each other. The outer surface of the side wall of the main filter 26 includes a corresponding element 265 for the slide rail 30, by means of which the main filter 26 can be slid into the air purifier 10.

[0078] For example, in the transport and storage of fresh fruits and vegetables, ethylene removal is important, which is why potassium permanganate is used in the main filter 26. The filter material contained in the selected crate 261 can be, for example, Climecon CKP8 filter media, which includes alumina as a structural material and has a potassium permanganate concentration of at least 8% by weight of the filter media.

[0079] For example, the filter medium contained in the selected crate 261 may also be activated carbon (such as Climecon adsorption medium ECS), or a mixture of potassium permanganate and activated carbon (such as filter medium Climecon CEKP8). Activated carbon effectively removes various gases in the air, such as sulfur-containing gases.

[0080] The selected crate 261 can contain, for example, a glass tube coated with titanium dioxide, which removes gases, bacteria and viruses. Titanium dioxide requires ultraviolet radiation to accelerate the reaction. Therefore, in the case where a photocatalyst is used in the main filter, ultraviolet radiation is provided to the main filter. For example, the glass tube can have an outer diameter of 4 mm, a pore size of 2 mm and a length of 20 mm. Alternatively, a different material (e.g., aluminum oxide) can be used as the structural material of the photocatalyst (e.g., titanium dioxide).

[0081] After the crate 261, a fabric filter 262 comprising activated carbon is advantageously placed last in the direction of the air flow. This filter removes VOC gases and unpleasant odors in particular. In addition, the activated carbon filter arranged last in the direction of flow ensures that potassium permanganate and other chemical filter materials cannot be transported to the outside of the air purifier 10 via the air outlet 12.

[0082] The air purifier 10 according to the present invention has been extensively tested using a Climecon CKP8 filter medium with a total weight of 300 grams in the main filter 26. The potassium permanganate content is 8% by weight, that is, there are about 24 grams of potassium permanganate in the main filter 26. The mass of the filter medium was measured before and after each test, and the air purifier was used for 3-4 hours each time during the test. During the test, the mass of the filter medium of the main filter 26 did not decrease, but on the contrary, the mass increased due to the accumulation of moisture in the filter medium of the main filter 26. It can be estimated that moisture also helps to bind potassium permanganate. A small amount of potassium permanganate may still fall off from the surface of the filter medium, but this potassium permanganate cannot diffuse to the outside of the air purifier because any potassium permanganate that falls off from the filter medium will eventually be blocked by the filter (comprised of a tight fabric filter 262 of activated carbon) arranged at the end of the main filter 26. The filter of the air purifier 10 is usually replaced every about 4-6 months, depending on the use.

[0083] For example, the amount of filter material can be determined in such a way that, in the case of using Climecon CKP8 filter material in 200 cubic meters of storage / transport space, 300 g of filter material is used in the main filter 26. If the volume is doubled to 200 cubic meters, the mass of the filter medium is doubled to 600 g. The crate structure of the main filter 26 makes it very easy to modify the amount of filter material.

[0084] In the dry space, a fabric filter 262 may also be used in the main filter 26, wherein one side of the fabric filter 262 is a non-woven fabric including titanium dioxide and nanosilver, and the other side is a non-woven fabric including activated carbon. A plurality of such fabric filters 262 may also be arranged in series as required.

[0085] The number of crates 261 and fabric filters 262 used in the main filter 26 is selected based on the air volume of the space, the plants stored in the space, and the required fan speed.

[0086] The top of the main filter 26 includes a cover 266 which is Figure 226 is visible as the uppermost portion of the main filter 26. The cover 266 locks the crate 261 and the fabric filter 262 within the main filter 26. In the case where a photocatalyst requiring UV radiation is used in the main filter, the cover 266 may be made of a highly light-transmitting plastic. The cover 266 of the main filter 26 may be made of, for example, polymethyl methacrylate, which has a permeability to UV radiation of approximately 55% at a thickness of 3 mm at a wavelength of 270 nm. The 2 mm thickness of the cover 266 is sufficient for structural strength, so if polymethyl methacrylate is used, the permeability increases to approximately 70%, and for some materials, the permeability increases to as high as 85%.

[0087] exist Figure 5 In the illustrated case, the air purifier 10 is arranged in a transport space 52 of a truck 50. The transport space 52 contains an air circulation refrigeration machine 54, by means of which the transport space 52 is kept at a selected temperature during transport to improve the preservation of the plants. The air purifier 10 is arranged on the ceiling of the transport space 52 close to the refrigeration device 54 so that it does not take up space for the load. The air purifier 10 is configured to draw its operating power from the refrigeration machine 54.

[0088] During the transportation process, the ethylene concentration of the transportation space 52 can be monitored in real time. The reading of the ethylene sensor 18 is sent to the server 35 by the data transmission device 20 via the network 34 at selected intervals (for example, at intervals of 30 seconds). The ethylene concentration of the transportation space 52 can be recorded in the memory by the recording device provided on the server 35. The server 35 can be accessed via the Internet 40 using a computer 36. The computer 36 can be, for example, a mobile phone of the driver of the truck 50. The same server 35 can provide services for multiple different transportation and storage spaces.

[0089] The network 34 may be any data communication network. Different options are for example GSM, GPRS, 3G, 4G, 5G and WLAN. The connection between the base station 41 and the server 35 is naturally operator-specific and is not important from the perspective of the present invention.

[0090] By means of a software device provided on the server 35, the system can be configured to trigger an alarm if the ethylene concentration in the transport space 52 exceeds a predefined threshold value (e.g., 20 ppm). For example, if the air purifier 10 that removes ethylene fails, the threshold value will be exceeded. An alarm can also be triggered if the parameters describing the operation of the air purifier 10 sent to the server indicate a device failure. For example, if the ethylene concentration exceeds a threshold value or the air purifier 10 fails during the transportation of the plant, an alarm can be transmitted to the mobile phone of the driver of the truck 50, so that the transport space 52 can be ventilated immediately to reduce the ethylene concentration or check the operation of the air purifier 10. Alternatively, an automatic ventilation device can be provided in the transport space 52, which will automatically turn on if the ethylene concentration exceeds a threshold value.

[0091] The air purifier 10 may also be used in plant storage spaces, for example, in refrigerated spaces in stores where fruits, vegetables and flowers await sale.

[0092] The system according to the invention allows the storage and transport of, for example, tomatoes and flowers in the same space, which would not be possible without effective air purification due to the accumulation of ethylene.

[0093] Although the system according to the invention is mainly aimed at food applications, it is clear that the use of the system is not limited to the example shown, but can be used to purify the air in any space using selected filter materials.

[0094] Figure 6 The ethylene concentration in a closed space as a function of time is shown. Ethylene was removed from a space of 28*38*58 cm in size by means of a system according to the invention in which potassium permanganate, titanium dioxide and nanosilver were used as active ingredients in the filter material for removing ethylene. More specifically, Figure 6 In the system used in the depicted test, the main filter contains 300g of Climecon CKP8 filter media, which includes potassium permanganate, and the pre-filter includes ultraviolet-activated titanium dioxide and nanosilver. First, a gas mixture containing ethylene is introduced into the space, and the ethylene concentration in the space is increased to 20ppm within a time interval T1 (i.e., within a time interval of 0-7 minutes). Then, the introduction of ethylene into the space is stopped, and the space is kept stable within a time interval T2 (i.e., within a time interval of 7-33 minutes). At 33 minutes, the air purifier 10 according to the present invention is turned on, and within a time interval T3 (i.e., within a time interval of 33-40 minutes), the ethylene in the space can be completely removed. Based on the measurement results, the air purifier 10 according to the present invention is able to remove ethylene at a rate of 3ppm / min, which is many times higher than, for example, an air purifier using only titanium dioxide.

Claims

1. A system for purifying air in a closed storage / transportation space, the system comprising an air purifier (10), the air purifier (10) comprising: - a housing having an air inlet (11) and an air outlet (12), wherein an air flow channel is located within the housing between the air inlet (11) and the air outlet (12), a fan (22) configured to draw air from the storage / transport space into the flow channel in the air purifier (10) via the air inlet (11), and to blow the purified air back into the storage / transport space via the air outlet (12), a filter system arranged in the flow channel in such a way that air flows through the filter system, wherein the filter system comprises both an ultraviolet-activated photocatalyst and a chemical filter material comprising potassium permanganate as chemical filter material, and - a UV emitting light source (23) for activating the photocatalyst of the filtering system, It is characterized in that - The filtration system comprises a main filter (26) forming a box comprising at least two crates (261), wherein the filter material contained in a first crate (261) comprises potassium permanganate and the second crate (261) comprises a selected chemical filter material, and wherein air is caused to flow through the crates (261).

2. The system according to claim 1, characterized in that The system also includes an ethylene sensor that measures the ethylene concentration in the air of the storage / transport space (18).

3. The system according to claim 2, characterized in that The system further comprises: a data transmission device (20) for transmitting the measurement data generated by the ethylene sensor (18) to a server; and a recording device for recording the measurement data.

4. The system according to any one of claims 1 to 3, characterized in that The main filter (26) also comprises at least one fabric filter (262), the at least one fabric filter (262) advantageously comprising a selected chemical filter material.

5. The system according to any one of claims 1 to 4, characterized in that The crate (261) is removable from the box.

6. The system according to any one of claims 1 to 5, characterized in that The main filter (26) comprises 2 to 8 crates (261), advantageously 4 to 6 crates (261).

7. The system according to any one of claims 1 to 6, characterized in that The main filter (26) of the air purifier (10) comprises at least one crate (261), the filter material contained in the at least one crate (261) comprising an ultraviolet activated photocatalyst, advantageously a glass tube coated with titanium dioxide.

8. The system according to claim 7, characterized in that The main filter (26) of the air purifier (10) has a cover (266) made of highly light-transmitting plastic, preferably a cover (266) made of polymethyl methacrylate, preferably, the thickness of the cover (266) is 2-4 mm, more preferably, the thickness of the cover (266) is 2-3 mm.

9. The system according to any one of claims 1 to 8, characterized in that The main filter (26) of the air purifier (10) comprises a fabric filter (262), the fabric filter (262) comprises activated carbon, and advantageously, the fabric filter (262) is the last filter in the filtration system in the direction of air flow.

10. The system according to any one of claims 1 to 9, characterized in that The ultraviolet-activated photocatalyst of the air purifier (10) is titanium dioxide, copper oxide or zinc oxide.

11. The system according to any one of claims 1 to 10, characterized in that The filtration system of the air purifier (10) further comprises activated carbon and / or nano silver as filtration materials.

12. The system according to any one of claims 1 to 11, characterized in that The ultraviolet emitting light source (23) of the air purifier (10) is a short-wave ultraviolet emitting LED having a wavelength of 255-275 nm.

13. The system according to any one of claims 1 to 12, characterized in that The air purifier (10) comprises an auxiliary light source (231), which is advantageously a blue light emitting LED.

14. The system according to any one of claims 1 to 13, characterized in that The main filter (26) of the air purifier (10) is fixed in the flow channel by a fixing device in such a way that the main filter (26) can be removed without tools.

15. The system according to any one of claims 1 to 14, characterized in that The main filter (26) of the air purifier (10) is arranged in the housing by means of a slide rail (30) in such a way that the main filter (26) can be removed without opening the housing.

16. The method according to claims 1 to 15, characterized in that The filtration system of the air purifier (10) further comprises a pre-filter (24) arranged in the flow channel, wherein the pre-filter (24) comprises a non-woven fabric, and the non-woven fabric comprises a selected chemical filter material.

17. The system according to claim 16, characterized in that The pre-filter (24) is arranged in the flow passage upstream of the main filter (26) along the air flow direction.

18. The system according to any one of claims 16 to 17, characterized in that The nonwoven fabric of the pre-filter (24) of the air purifier (10) comprises a UV-activated photocatalyst, advantageously titanium dioxide, and the UV-emitting light source (23) is directed towards the pre-filter (24).

19. The system according to any one of claims 16 to 18, characterized in that The pre-filter (24) of the air purifier (10) is fixed in the flow channel by a fixing device in such a way that the pre-filter (24) can be removed without tools.

20. The system according to any one of claims 16 to 19, characterized in that The pre-filter (24) of the air purifier (10) is arranged in the housing by means of a slide rail (30) in such a way that the pre-filter (24) can be removed without opening the housing.

21. The system according to any one of claims 2 to 20, characterized in that The system comprises software means configured to trigger an alarm if the ethylene concentration measured by the ethylene sensor (18) exceeds a predefined threshold.

22. A system according to any one of claims 2 to 21, characterized in that The system includes software means for reading real time ethylene concentration and parameters describing the operation of the air purifier which are added to the measurement data.

23. The system according to any one of claims 1 to 22, characterized in that The storage / transportation space includes an air circulation refrigerator (54), the air purifier (10) is arranged on the ceiling of the storage / transportation space near the refrigerator (54), and the refrigerator (54) of the storage or transportation space is configured to supply power to the air purifier (10).

24. A system according to any one of claims 2 to 23, characterized in that The system comprises software means for regulating the power of the fan (22) and / or for activating the fan (22) when the ethylene concentration measured by the ethylene sensor (18) exceeds a predetermined threshold value.

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