RU100189U1 - CONVECTIVE TYPE PHOTOCATALYTIC CLEANER - Google Patents

Abstract

 1. A convective-type photocatalytic air purifier comprising a vertically arranged housing with lower and upper ends open for passage of air flow, inside which a lamp is installed that illuminates the anatase-modified photocatalytic element between the housing and the lamp, characterized in that the housing is made of opaque material, the photocatalytic element is made of sintered glass beads, the surface of which is coated with nanocrystalline titanium dioxide powder and with a specific surface area of 100-400 m2 / g, and as a lamp it contains one or more ultraviolet lamps with a range of ultraviolet A (400-315 nm). ! 2. The photocatalytic air purifier according to claim 1, characterized in that the housing is made primarily of black, stainless steel or aluminum, and its cross section is mainly in the shape of a circle, square or rectangle. ! 3. The photocatalytic air purifier of claim 1, characterized in that the housing has fasteners that allow wall, desktop or floor installation with the possibility of connecting to the battery of cascade or parallel types. ! 4. The photocatalytic air purifier according to claim 1, characterized in that the photocatalytic element is made of interconnected sintered glass balls with a predominantly diameter of 0.8-1.5 mm, plates or cylinders forming a cavity that allows the installation of one or more inside this cavity ultraviolet lamps with a gap from the side surface of the photocatalytic element equal to 0.1-2.5 of the outer diameter of the lamp. ! 5. Photocatalytic air purifier according

Description

The utility model relates to ecology, namely to devices that purify indoor air from molecular organic and biological pollutants (harmful chemicals, odors, allergens, viruses, bacteria, etc.)

The most effective way to remove molecular organic and biological air pollutants is currently recognized technology based on the use of photocatalysis. The essence of the photocatalytic method is the decomposition and oxidation of toxic organic impurities, viruses and bacteria on the surface of the photocatalyst under the influence of ultraviolet radiation, while the impurities do not accumulate, but are mineralized to harmless components.

Main applications of convective photocatalytic air purifiers:

1. Cleaning and disinfection of air in the premises of microbiological industries (for example, the production of yeast).

2. Cleaning and disinfection of air in the premises of medical institutions (patient wards, operating rooms, dressing rooms, etc.).

3. Cleaning and disinfecting air in laboratory rooms where chemical and biological experiments are performed.

4. Air purification and disinfection in city apartments, in hotel rooms and in office premises.

5. Cleaning and disinfection of air in the cabin of aircraft, trains and other vehicles.

6. Air purification at the outlet of the ventilation systems of kitchens, garages, chemical, biological and food industries.

7. Air purification from vapors of substances (for example nitroglycerin) that are dangerous for accumulation in adsorbents.

8. Destruction of ethylene in vegetable stores of fruits and vegetables.

9. Purification of air from tobacco smoke and tobacco products. Known air purifier (patent of the Russian Federation No. 2352382, class A61L 9/20, publ. 04/20/2009), which includes a fan, a mechanical cleaning filter that traps large particles of dust, an electrostatic filter that traps aerosol particles and a carbon-photocatalytic filter for sterilizing air and purifying it from molecular pollutants. This is a universal cleaner, the main disadvantages of which are:

1. The limited efficiency of purification from molecular pollutants due to the disproportionately large stream of purified air, compared with the limited power of the used ultraviolet lamps.

2. Increased noise due to pressure fan.

3. The need for a specialized after-sales service for the periodic replacement of complex filter elements of the cleaner, in which harmful pollutants accumulate, as a result of which these elements can themselves become sources of pollution. Known air purifier (US patent No. 2007/0295213 A1, publ. 12/27/2007). It is also a universal cleaner in which seven stages of air purification are sequentially implemented:

1. Pre-filter with catechin to remove large particles of dust and pet hair from the air. Catechin is a natural antibacterial substance extracted from tea leaves that has the ability to destroy viruses and bacteria.

2. A bio-antibody filter to capture airborne viruses.

3. Plasma ionizer for charging dust particles and plant pollen with positive charges for their subsequent direction into the electrostatic filter.

4. Flash Streamer device for generating high-speed electrons that destroy odor carriers and molecular pollutants, such as formaldehyde.

5. Flash Streamer device for activating a photocatalytic reaction on the surface of a titanium apatite photocatalytic filter that removes bacteria and viruses.

6. An electrostatic filter with negatively charged plates to absorb dust particles and pollen from plants positively charged in a plasma ionizer.

7. Deodorizing catalyst for the absorption and destruction of the remaining odors before the release of purified air into the room.

The main disadvantages of this air purifier, as in the previous device, are:

1. The limited effectiveness of air disinfection and purification from molecular pollutants due to the disproportionately large flow of cleaned air, compared with the limited power of the used ultraviolet lamps, especially in forced operation modes of the fan.

2. Increased noise due to pressure fan.

3. The need for a specialized after-sales service for the periodic replacement of complex filter elements of the cleaner, in which harmful pollutants accumulate, as a result of which these elements can themselves become sources of pollution.

4. The relatively high level of cost of the cleaner. Known air purifier (patent of the Russian Federation No. 2259850 C1, CL. A61L, publ. 10.09.2005), in which air purification includes the following steps:

1. Mechanical cleaning of large and small particles.

2. Absorption of various odors.

3. Bactericidal radiation to remove microorganisms.

4. Photocatalytic decomposition of gaseous chemical pollutants.

To increase the oxidation state of molecular pollutants in this device, first, by means of mechanical filtration, they purify the air from large and small particles and various odors, after which part of the purified air is taken out of the device into the room, and the remaining part of the air is irradiated with an ozone-free ultraviolet bactericidal lamp to suppress microorganisms and cleaned from gaseous contaminants by oxidizing them on the surface of the photocatalyst. This technique should reduce the presence of peroxides in the purified air, but the overall efficiency of the device (in terms of the total air flow) in disinfecting and cleaning it from molecular pollutants remains insufficient. Thus, this device has the following main disadvantages:

1. The limited effectiveness of air disinfection and purification from molecular pollutants due to the not proportionally large flow of cleaned air compared with the limited power of the used ultraviolet lamps.

2. Increased noise due to pressure fan.

3. The need for a specialized after-sales service for the periodic replacement of filter elements of the cleaner, in which harmful pollutants accumulate, as a result of which these elements can themselves become sources of pollution.

Analysis of the shortcomings of the above air purification devices, especially the presence of significant noise from the fans, limits the significant sector of their application in schools and kindergartens, in hospitals and sanatoriums, in residential premises, in sleeping rooms of hotels, and many other similar habitats for people in closed spaces. For mass “social” consumption in the indicated sector of application, it is necessary to be highly efficient in work, easy to set up and accessible to economically wide sections of the population.

The rejection of fans and the transition to other ways of organizing air flows is one of the rational ways to solve this problem. It is known that in a vertical (or close to vertical) channel with an inhomogeneous distribution of temperature and, accordingly, air density, free gravitational motion (free convection) occurs and natural draft appears, forming air flows. In this case, the pumped volumes of air are proportional to the length of the channel and the temperature inside the channel, which under certain conditions can ensure the performance of convective devices for pumped air, comparable with fan devices.

Known fanless photocatalytic air purifier (patent of Russian Federation No. 2334176 C1, CL. F24F 13/00, publ. 09/20/2008) for air purification in industrial premises, including a housing with open upper and lower ends, on the outside of the housing there is an industrial frequency inductor, An induction lamp is installed on the axis of the housing, and heating elements of a ferromagnetic material with a deposited catalyst layer are placed on the inner side surface of the housing. Under the influence of the electromagnetic field of the external inductor, ferromagnetic elements are heated, sufficient for the occurrence of natural air draft, which, passing in the space between the lamp and the catalyst, is cleaned of pollutants. The disadvantage of this air purifier is its unsuitability for cleaning rooms in which a person has been staying for a long time, as well as the large bulkiness and heavy weight of induction heating generators, which are not acceptable for residential premises.

The closest to the set of essential features of this utility model is a convective photocatalytic air purifier (US patent No. 20080131311 A1, CL A61L 9/00, published 05.06.2008), containing a transparent round casing, along the axis of which a fluorescent lamp is installed, and between the lamp and the body is a round transparent, porous photocatalytic element. In this lamp, at the same time as an air purifier, noise is completely eliminated due to the fact that the flow of cleaned air is carried out in free convection mode (without using a fan).

The disadvantage of this device is the insufficient intensity of convective air flow, the insufficient efficiency of daylight lamps for cleaning and disinfecting air and its unsuitability for work in sleeping rooms at night.

The objective of the technical solution is to eliminate the above disadvantages.

The problem is solved by the inventive, photocatalytic convective type air purifier containing a vertically located housing with lower and upper ends open for passage of air flow, inside which a lamp is installed that illuminates the anatase-modified photocatalytic element located between the housing and the lamp, in which the housing is made of an opaque material, the photocatalytic element is made of sintered glass beads on the surface of which nanocrystals are deposited esky titanium dioxide powder having a specific surface area of 100-400 m ² / g, and as a lamp it contains one or more ultraviolet lamps UV A range (400-315 nm).

The body of the photocatalytic air purifier is made primarily of black, stainless steel or aluminum, and its cross section is mainly in the shape of a circle, square or rectangle. The housing has fasteners that allow wall, table or floor installation with the possibility of connecting to the battery of cascade or parallel types.

The photocatalytic element is made of interconnected sintered glass balls of predominantly 0.8-1.5 mm diameter, plates or cylinders forming a cavity that allows the installation of one or more ultraviolet lamps inside this cavity with a gap of 0.1 from the side surface of the photocatalytic element -2.5 of the outer diameter of the lamp.

In the inventive photocatalytic air purifier, the height of the housing exceeds the height of the lamp installed inside the housing by 5-20%. The photocatalytic element is equipped with a heating device in the form of electrical resistance for additional heating of the element or air flow.

The technical result of this utility model is expressed:

1. In increasing the intensity of convective air flow.

2. In the complete prevention of light transmission of the convective photocatalytic air purifier body and the achievement of the possibility of its operation in rooms for rest of people, including at night.

3. In increasing the efficiency of the purifier for air disinfection and its purification from molecular chemical and biological pollutants. The essence of the utility model is as follows. From gas dynamics it is known that the flow of natural thrust in a vertical channel is proportional to the cross section of the channel and depends on the height of the channel to the power of 0.5. To the same extent, the thrust flow is proportional to the difference in temperature inside the channel and the temperature of the outside air. Based on this, to increase the intensity of convective air flow, the following tools are proposed that are essential features of this utility model: a photocatalyst carrier made of sintered glass balls with a low coefficient of thermal conductivity. Such a photocatalytic element, due to minimal thermal conductivity, ceteris paribus, allows the maximum use of the heat generated inside the purifier to create maximum natural draft, which determines the performance of the device by the cleaned air.

The heater of the photocatalytic element is made in the form of electrical resistance for additional heating of the element or air flow, providing for the combined heating of the air (including its heating from ultraviolet lamps).

The cleaner body has external lateral fasteners for cascade connection of several cleaners, which increases the height of the channel and, accordingly, the device’s air productivity.

To completely prevent light transmission of the convective photocatalytic air purifier housing and to achieve the possibility of its operation in rooms for rest of people, including at night, its housing is made of opaque material with a low reflection coefficient, mainly of black, stainless steel and aluminum, and light transmission through the upper and lower ends of the device are prevented by the use of light-absorbing screens.

Since the main function of the product that is closest in terms of the essential features to this utility model is the function of a luminaire, for which a typical fluorescent lamp with a minimum fraction of ultraviolet radiation power is used, the effectiveness of such a product in disinfecting air and cleaning it from molecular pollutants is insufficient. To increase the efficiency of this function of the purifier, the following tools are proposed, which are essential features of this utility model:

The cleaner is equipped with one or more lamps with a long-wavelength range of ultraviolet A (400-315 nm) installed inside the cleaner body. From experience with various ultraviolet lamps it follows that the installation of the specified ultraviolet lamp instead of a conventional daylight lamp increases the concentration of active oxygen particles on the surface of the photocatalyst participating in the oxidation of pollutants by orders of magnitude.

In the claimed utility model, the photocatalytic element has a highly branched surface made of sintered glass beads or ceramics, the surface of which is coated with anatase nanocrystalline titanium dioxide with a specific surface area of 100-400 m ² / g. According to the operating experience, such a photocatalytic element, due to the minimum thermal conductivity, has maximum efficiency, since, ceteris paribus, it allows the maximum use of the heat generated inside the purifier for the photocatalytic oxidation of harmful pollutants.

The photocatalytic element is made of interconnected plates or cylinders that form a cavity that allows the installation of one or more ultraviolet lamps inside this cavity with a gap from the side surface of the photocatalytic element equal to 0.1-2.5 of the outer diameter of the lamp, which ensures maximum ultraviolet flux density radiation to the surface of the photocatalyst.

The purifier body has external lateral fastenings for battery connection of several purifiers, which allows for optimal air purification parameters depending on the size of the room and the concentration of pollutants in it.

The purifier body has a bracket that allows wall mounting, desktop and floor installation, which allows to ensure the optimal location of the air purifier depending on the purpose of the room, its area and configuration, as well as on the local concentration of pollutants.

The scheme of the device photocatalytic convective type air purifier according to US patent No. 20080131311 A1, CL. A61L 9/00, publ. 06/05/2008, FIG. 7B (prototype) is shown in FIG. 1:

1 - transparent case; 2 - light transmission photocatalytic element;

3 - fluorescent lamp.

Figure 2. contains a testing scheme for a convective photocatalytic air purifier:

1 - sealed glass box with a volume of 300 liters; 2 - photocatalytic device; 3 - contaminant dispenser; 4 - a device for measuring the concentration of CO ₂ Klimalogger KL 201; 5 - personal computer.

In figure 3. The scheme of the claimed utility model of a convective photocatalytic air purifier with one ultraviolet lamp is shown:

1 - casing of opaque material; 2 - photocatalytic element of sintered glass balls; 3 - ultraviolet lamp with a long-wavelength range of ultraviolet A (400-315 nm); 4 - light-absorbing screen for the flow of purified air; 5 light-absorbing screen for the flow of polluted air; View along arrow AA: type 1 - rectangular section of the casing: type 2 - square section of the casing; type 3 - round section of the body.

Figure 4. contains a diagram of a useful model of a convective photocatalytic air purifier with two ultraviolet lamps:

1 - case of rectangular cross section made of opaque material; 2 - photocatalytic element of sintered glass balls; 3 - two ultraviolet lamps with a long-wavelength range of ultraviolet A (400-315 nm); 4 - a light-absorbing screen for the flow of purified air; 5 - light-absorbing screen for the flow of polluted air.

Figure 5 - diagram of a utility model in the form of a cascade of two cleaners:

1 - photocatalytic convective type air purifier with one ultraviolet lamp according to this application; 2 - photocatalytic convective type air purifier with one ultraviolet lamp according to this application.

6 is a diagram of a utility model of a photocatalytic convective type air purifier with one ultraviolet lamp and an additional heating device:

1 - casing of opaque material; 2 - photocatalytic element of sintered glass balls; 3 - ultraviolet lamp with a long-wavelength range of ultraviolet A (400-315 nm); 4 - light-absorbing screen for the flow of purified air; 5 light-absorbing screen for the flow of polluted air; 6 heating device in the form of electrical resistance for additional heating of the air flow.

The implementation of the utility model is confirmed by the following examples.

Example 1

Convective fluorescent device (figure 1) with photocatalytic air purification and a transparent body (1) is assembled according to US patent No. 20080131311 A1, CL. A61L 9/00, publ. 06/05/2008 (prototype). For this, a nanocrystalline anatase-modified titanium dioxide powder with a specific surface area of 280 m ² / g is applied to a photocatalytic element (2) made of fiberglass. One fluorescent lamp (3) OSRAM DULUX L 36 W / 827 was installed in the inner cavity of the photocatalytic element.

This device prototype was tested on a stand, a diagram of which is shown in figure 2. The efficiency of the device was estimated by the rate of CO ₂ accumulation resulting from the photocatalytic oxidation of acetone vapor. To measure the rate of accumulation in a sealed chamber (1) with a volume of 300 liters, a device assembled according to the prototype was placed (2). Using dispenser (3), 0.8 g of acetone was introduced into the chamber, then the device under test was turned on, and the process of increasing the concentration of carbon dioxide (CO ₂ ) resulting from the photocatalytic oxidation of acetone vapor was observed at room temperature. To measure the concentration of CO _{2, we} used the Klimalogger KL 201 instrument (4) connected to a personal computer (5). The CO ₂ formation rate measured for 1 hour for the device under test was 5 · 10 ^-7 mol / min.

Example 2

The photocatalytic air purifier, assembled according to the scheme (figure 3) of this application, had a steel case (1) of rectangular cross-section (type 1) (height - 510 mm, width 175, depth 55 mm). A photocatalytic element of plates (2) sintered from glass beads with a diameter of 0.8 mm was mounted on the surface of the nanocrystalline anatase titanium dioxide powder with a specific surface area of 280 m ² / g. A single ultraviolet lamp (3) with a long-wavelength range of ultraviolet A (400-315 nm) Phillips PL-L Cleo 36 W is installed in the inner cavity of the photocatalytic element along the axis of the housing; The housing is equipped with a light-absorbing screen (4) for the flow of purified air and a light-absorbing screen (5 ) for the flow of polluted air.

The test procedure was similar to Example 1. The CO ₂ formation rate measured for 1 hour for the inventive convective type photocatalytic air purifier was 7.92 ·· 10 ^-5 mol / min.

Example 3

Similar to example 2 with the difference that two ultraviolet lamps Phillips PL-L Cleo 36 W were installed in the inner cavity of the photocatalytic element. The CO ₂ formation rate measured in 1 hour was 13.84 · 10 ^-5 mol / min.

Example 4

Similar to example 2 with the difference that two photocatalytic purifiers are connected in a cascade type battery, forming a device with a total height of 1,500 mm. Measured in 1 hour, the rate of formation of CO ₂ was 11.29 · 10 ^-5 mol / min.

Example 5

Similar to example 2 with the difference that a resistor with a rated power dissipation of 40 watts is installed in the internal cavity of the photocatalytic element. Measured for 1 hour, the rate of formation of CO2 was 17.60-10 ^-5 mol / min.

A comparison of the work of the prototype (example 1) with the options for the implementation of a convective photocatalytic air purifier (examples 2, 3, 4 and 5) proposed in the application shows (table 1) a significant increase in its efficiency compared to the prototype.

Table 1. The efficiency of various options photocatalytic air purifier convective type. Example Device option The accumulation rate of CO ₂ , 10 ^-5 mol / min one Prototype US Pat. No. 20080131311 0.05 2 Single Lamp Photocatalytic Cleaner 7.92 3 Two-lamp photocatalytic cleaner 13.84 four Two-lamp photocatalytic cleaner 11.29 5 Photocatalytic cleaner with resistor 17.60

Example 6. Tests of photocatalytic devices for air disinfection were carried out in a box of 300 liters (1), shown in figure 2. Before each new test, accompanied by a change in the photocatalytic device, the box was treated with a 0.33% analyte disinfectant solution and irradiated with open type portable bactericidal lamps for 1 hour. Tests began 1 hour after completion of the preparatory work.

An aerosol of the bacteria Es-cherichia coli was used as a model pollutant. This pollutant was sprayed using an RJ-4M removable dispenser-sprayer (3). In order to slow down the settling of the aerosol of bacteria on the walls of the box, a portable fan was used to maintain the initial high concentration of bacteria in the air for at least 100 minutes at the level of 3000 CFU / m ³ (CFU - colony forming units), which was confirmed by preliminary measurements.

To determine the quantitative content of bacteria in the air during the operation of the tested device in the box, an impactor for sampling air (Flora-100 model) was used in automatic mode with the selection of a given volume of air of 33 liters and the deposition of microorganisms contained in it on a Petri dish with a dense nutrient Wednesday. Table 2 shows the comparative results of the prototype (figure 1) and the device proposed in this application (figure 3) for air disinfection using the model bacterial contaminant as an example.

Table 2. Comparative data on air disinfection. Photocatalytic device The effectiveness of disinfection (%) Prototype device 43.5 Suggested device 99.9

As can be seen from the above examples in tables 1 and 2, the proposed convective type photocatalytic air purifier device can be used in a new series of photocatalytic purification and disinfection devices for air and other gases to solve a wide range of domestic and technical problems.

Thus, the inventive photocatalytic purifier can improve the efficiency of air purification and its disinfection of molecular chemical and biological pollutants. The inventive device has an increased intensity of convective air flow. The light transmission of the convective photocatalytic air purifier was prevented, and it was possible to work in rooms for rest of people, including at night.

Claims (6)

1. A convective-type photocatalytic air purifier comprising a vertically arranged housing with lower and upper ends open for passage of air flow, inside which a lamp is installed that illuminates the anatase-modified photocatalytic element between the housing and the lamp, characterized in that the housing is made of opaque material, the photocatalytic element is made of sintered glass beads, the surface of which is coated with nanocrystalline titanium dioxide powder and with a specific surface area of 100-400 m ² / g, and as a lamp it contains one or more ultraviolet lamps with a range of ultraviolet A (400-315 nm). 2. The photocatalytic air purifier according to claim 1, characterized in that the housing is made primarily of black, stainless steel or aluminum, and its cross section is mainly in the shape of a circle, square or rectangle. 3. The photocatalytic air purifier of claim 1, characterized in that the housing has fasteners that allow wall, desktop or floor installation with the possibility of connecting to the battery of cascade or parallel types. 4. The photocatalytic air purifier according to claim 1, characterized in that the photocatalytic element is made of interconnected sintered glass balls with a predominantly diameter of 0.8-1.5 mm, plates or cylinders forming a cavity that allows the installation of one or more inside this cavity ultraviolet lamps with a gap from the side surface of the photocatalytic element equal to 0.1-2.5 of the outer diameter of the lamp. 5. The photocatalytic air purifier according to claim 1, characterized in that the height of the housing exceeds the height of the lamp installed inside the housing by 5-20%. 6. The photocatalytic air purifier according to claim 1, characterized in that the photocatalytic element is equipped with a heating device in the form of electrical resistance for additional heating of the element or air flow.