Indoor air purification device based on visible light-responsive photocatalyst

Abstract

The present invention relates to an indoor air purification device capable of performing an air purification function along with an indoor lighting function on the basis of a visible light-responsive photocatalyst, the indoor air purification device comprising: a main body having a plurality of intake holes through which outside air is introduced; an LED connected to a connector provided on the upper part of the main body and emitting light in the visible light wavelength region; and a glass tube fixed and supported by the main body or the connector and surrounding the LED lamp, wherein the glass tube is formed as a double glass tube composed of two glass tubes of different inner diameters, and provides an air passage through which the introduced air flows, and a visible light-responsive photocatalyst can be applied to the inner surface of a first glass tube and the outer surface of a second glass tube in contact with the air passage.

Description

Visible light-responsive photocatalyst-based indoor air purifier

[0001] The present invention relates to an indoor air purification device, and more particularly, to an indoor air purification device capable of performing air purification together with indoor lighting based on a visible light responsive photocatalyst.

[0002] Air purifiers remove fine dust, allergens, and organic pollutants from the air. With increasing indoor air pollution, their use is rapidly increasing in various settings, including homes, offices, hospitals, and schools. While various filters are typically used to enhance pollutant removal efficiency, there has been a recent increase in the use of photocatalytic technologies that eliminate the need for air filters.

[0003] A photocatalyst is a type of catalyst that is a substance whose catalytic action occurs when it receives light energy. In other words, it is a substance that uses light as an energy source to promote a catalytic reaction (oxidation / reduction reaction) and decomposes various bacteria and pollutants. When irradiated with light with an energy higher than the band gap, electrons (e-) with a negative charge and holes (h+) with a positive charge are generated, and various reactions occur, such as decomposing ionic or molecular species in a solution through strong reduction or oxidation.

[0004] Materials that can be used as photocatalysts include TiO2 (anatase), TiO2 (rutile), ZnO, CdS, ZrO2, SnO2, V2O3, WO3, and perovskite-type composite metal oxides (SrTiO3). Among these, TiO2 is the most widely used material among photocatalysts, as it has a very strong oxidizing power that absorbs light and oxidizes other substances, and has a strong oxidizing power, so it is insoluble in almost all solvents such as acids, bases, or aqueous solutions, and also does not undergo biological reactions, so it is safe and harmless to the environment and human body.

[0005] However, since the band gap of photocatalysts such as titanium dioxide is 3.0-3.3 eV, a light source in the ultraviolet range is required to overcome this band gap. Therefore, the photocatalyst is activated by continuously irradiating it with ultraviolet rays in the range of 350-380 nm. However, the ultraviolet rays in sunlight reaching the ground only account for 3-5%, and the proportion that can be utilized in indoor lighting is even smaller. Therefore, the development of visible light-responsive photocatalysts that can utilize visible light, the main component of sunlight and indoor lighting, has been actively researched recently.

[0006] The technical problem to be solved by the present invention is to provide an indoor air purification device that can perform an air purification function together with indoor lighting based on a visible light responsive photocatalyst.

[0007] An indoor air purification device according to the present invention for solving the above-described technical problem comprises: a main body having a plurality of inlet holes through which outside air is introduced; an LED lamp connected to a connector provided on an upper portion of the main body and irradiating light in a visible light wavelength range; and a glass tube formed to surround the LED lamp and fixed and supported by the main body or the connector; wherein the glass tube is formed as a double glass tube having different inner diameters to provide an air passage through which the introduced air flows, and a visible light-responsive photocatalyst may be applied to the inner surface of a first glass tube and the outer surface of a second glass tube in contact with the air passage.

[0008] According to an embodiment, one side of the glass tube may have hemispherical bends formed at regular intervals toward the air passage.

[0009] According to an embodiment, the device may further include a blower fan that introduces air into the interior of the main body and discharges the introduced air to the outside through the air passage.

[0010] According to the present invention, by using a visible light-responsive photocatalyst, a visible light lamp can be used as a light source, thereby achieving the effect of performing both indoor lighting and air purification functions.

[0011] In addition, by applying a photocatalyst between the double glass tubes around the lamp and introducing outside air, the probability of contact between the polluted air and the photocatalyst can be increased, and the adsorption of pollutants on the surface of the photocatalyst and the efficiency of the photochemical reaction can be increased.

[0012] In addition, by forming a bend in the air passage between the glass tubes, the surface area of ​​the photocatalyst can be expanded and the flow and speed of air can be restricted, thereby accelerating the photocatalytic reaction rate.

[0013] FIG. 1 is a perspective view showing an indoor air purification device according to an embodiment of the present invention.

[0014] Figure 2 is a cross-sectional view showing the inside of the upper part of the main body of an indoor air purification device according to an embodiment of the present invention.

[0015] Figures 3 to 5 are drawings showing cross-sections of a double glass tube according to an embodiment of the present invention.

[0016] In order to explain in detail the technical idea of ​​the present invention to a degree that a person having ordinary skill in the art to which the present invention pertains can easily practice the present invention, the most preferred embodiment of the present invention will be described with reference to the attached drawings.

[0017] First, when adding reference signs to the components of each drawing, it should be noted that identical components are given the same signs whenever possible, even if they are shown on different drawings.

[0018] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings attached to this specification.

[0020] FIG. 1 is a perspective view showing an indoor air purification device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the inside of the upper part of the main body of the indoor air purification device according to an embodiment of the present invention.

[0021] Referring to FIGS. 1 and 2, an indoor air purifier (100) according to the present invention is configured to include a main body (110), an LED lamp (130) coupled to the upper portion of the main body (110), and a glass tube (150) formed to surround the LED lamp (130).

[0022] A number of inlet holes (111) are formed on the lower side of the main body (110) to allow external air to flow in, and an operating unit (112) that can control the on / off of the LED lamp (130) and the blower fan (113), the color and brightness of the lamp, and the wind speed can be provided.

[0023] An air filter (121), for example, a HEPA filter, may be installed inside the upper part of the main body (110) to primarily remove fine dust contained in the inflowing air, and a blower fan (122) may be provided above the air filter (121). The blower fan (122) is used to smoothly inflow and exhaust air, and the efficiency of antibacterial and air purification by photocatalytic reaction can be increased by controlling the speed.

[0024] A step portion (113) is formed along the inner surface of the upper part of the main body (110), and a first insertion groove (114) having a groove of a certain depth is provided in the step portion (113) so that a first glass tube (151) can be inserted and supported. A connector (123) for electrical connection with an LED lamp (130) is provided in the upper center of the main body (110). The connector (123) may be formed in a cylindrical shape and may be fixed while maintaining a certain distance from the inner wall of the main body (110). Accordingly, air coming out through the blower fan (122) is distributed and flows along the annular passage formed between the main body (110) and the connector (123).

[0025] A second insertion groove (124) with a groove of a certain depth dug along the outer circumference may be formed on the upper surface of the connector (123), and a second glass tube (152) may be inserted into and supported in the second insertion groove (124).

[0026] The LED lamp (130) is a light source that emits visible light of about 400 nm to 700 nm as a main wavelength, and may be configured to include a socket connected to a connector (123), an LED array mounting a plurality of LEDs, a cover, etc. The LED lamp (130) may be manufactured in a long shape so as to provide sufficient light energy to a photocatalyst coated on a glass tube (150). Meanwhile, although the present invention uses an LED lamp as an example as a light source, it is not limited thereto, and it is obvious that the present invention may be replaced with any lighting device capable of irradiating visible light, such as a fluorescent lamp, an incandescent lamp, or a xenon lamp.

[0027] The glass tube (150) is in the form of a double tube and is composed of a first glass tube (151) and a second glass tube (152), which can be fixed and supported by being inserted into a first insertion groove (114) and a second insertion groove (124), respectively. An air passage (153) through which the introduced air flows is formed between the first glass tube (151) and the second glass tube (152), and the introduced air passes through the air passage (153) and undergoes a deodorization, sterilization, and purification process before being discharged to the outside through the outlet (154) at the top of the air passage (153).

[0028] Figures 3 to 5 are drawings showing cross-sections of a double glass tube according to an embodiment of the present invention.

[0029] Referring to FIG. 3, a photocatalyst (155) may be applied to the inner or outer surface of the glass tube (150), that is, the inner surface of the first glass tube (151) and the outer surface of the second glass tube (152) that are in contact with the air passage (153). The photocatalyst (155) is a semiconductor material that uses light as an energy source to promote a catalytic reaction (oxidation / reduction reaction) to decompose various bacteria and pollutants. When a photocatalyst such as titanium oxide that is commonly used is irradiated with ultraviolet rays having a wavelength of 380 nm or less, electrons in the valence band are excited to the conduction band, generating electrons with reducing ability and holes with oxidizing ability in the valence band. At this time, some of the generated electrons and holes diffuse to reach the surface and generate reactive species to cause a photocatalytic reaction.

[0030] However, the present invention uses a visible light responsive photocatalyst. That is, the photocatalyst (155) applied to the glass tube (150) is activated by a photocatalytic reaction in response to visible light of 400 nm to 750 nm. The visible light responsive photocatalyst can be manufactured by various known methods. For example, a method of injecting transition metal ions such as vanadium, chromium, iron, and manganese by accelerating them at high voltage into the interior of titanium oxide and roasting them again with oxygen, or a method of changing the position of the valence band by doping the oxygen position of titanium oxide with nitrogen or sulfur, etc. can be used.

[0031] Meanwhile, in order to maximize the deodorizing, sterilizing and air purifying functions by photocatalytic reaction, the light irradiated from the LED lamp (130) must sufficiently reach the photocatalyst (155), and the contaminated air within the air passage (153) must smoothly contact and be adsorbed on the surface of the photocatalyst (155).

[0032] Referring to FIG. 4, according to an embodiment of the present invention, the glass tube (150) may form an embossed curved portion (157) toward the air passage (153). Specifically, the curved portion (157) may be formed in a hemispherical shape at regular intervals (e.g., the diameter of the hemisphere) on the inner side of the first glass tube (151) and the outer side of the second glass tube (152). Such a curved portion (157) induces diffuse reflection of the irradiated light, thereby enabling light energy to be provided to all areas where the photocatalyst (155) is applied, and at the same time, increases the surface area of ​​the photocatalyst and limits the flow and speed of contaminated air flowing in the air passage (153), thereby maximizing the efficiency of the photocatalytic reaction.

[0033] Referring to FIG. 5, according to an embodiment of the present invention, one side of a glass tube (150) may have hemispherical curved portions (157) and flat portions (158) alternately appearing, and the curved portion (157) of the first glass tube (151) and the flat portion (158) of the second glass tube, and the flat portion (158) of the first glass tube and the curved portion (157) of the second glass tube may be formed in a form in which they face each other. In this case, the photocatalyst (155) may be applied only to a portion of the surface of the glass tube (150), i.e., only to the curved portion (157).

[0034] Due to the double glass tube structure, the light source irradiated from the LED lamp (130) located at the center passes through the second glass tube (151) and the photocatalyst coating layer (155) to reach the first glass tube (151). However, in the photocatalyst coating method as in the embodiment of FIG. 4, the amount of light energy reaching the second glass tube (152) may not be sufficient due to debris or adsorbed harmful substances resulting from the photocatalytic reaction in the first glass tube (151), and thus the efficiency of the photocatalytic reaction in the first glass tube (151) is bound to be low. The photocatalyst coating method of FIG. 5 is intended to solve this problem, and by allowing the irradiated light to pass through the flat portion (158) of the second glass tube (152) and directly reach the curved portion (157) of the first glass tube (151), a sufficient amount of light can be secured and an efficient photocatalytic reaction can occur on both sides of the glass tube.

[0035] As described above, the best embodiments have been disclosed in the drawings and specifications. While specific terminology has been used herein, it is solely for the purpose of describing the present invention and is not intended to limit the meaning or scope of the invention as defined in the claims. Therefore, those skilled in the art will understand that various modifications and equivalent embodiments are possible. Accordingly, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. A main body (110) having a plurality of inlet holes (111) through which outside air is introduced; An LED lamp (130) connected to a connector provided on the upper part of the main body and irradiating light in the visible light wavelength range; and A glass tube (150) is formed to surround the LED lamp and is fixed and supported by the main body or the connector; An indoor air purification device based on a visible light responsive photocatalyst, characterized in that the glass tube is formed as a double glass tube having different inner diameters to provide an air passage (153) through which the introduced air flows, and a visible light responsive photocatalyst (155) is applied to the inner surface of the first glass tube (151) and the outer surface of the second glass tube (152) that are in contact with the air passage.

2. In paragraph 1, A visible light responsive photocatalyst-based indoor air purification device characterized in that a hemispherical curved portion (157) is formed at regular intervals toward an air passage on one side of the glass tube.

3. In paragraph 2, A visible light responsive photocatalyst-based indoor air purification device characterized by further including a blower fan that introduces air into the interior of the main body and discharges the introduced air to the outside through the air passage.

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