Device and method for eliminating volatile organic compounds and microorganisms from indoor air

Abstract

The device comprises a casing (1), with the following three consecutive chambers (2, 3, 4): - a first chamber (2), with a fan (5) having blades (6) coated with SiO2 nanocrystals; - a second chamber (3), with: obstacles (7) for creating turbulence, and coated with SiO2 nanocrystals; ultraviolet light lamps (8); and a photocatalyst solution impregnating the inner walls (11) of the second chamber (3); and - a third chamber (4), with an ozone-free needlepoint bipolar air ionisation system, and from which purified air is expelled. The invention makes it possible to optimise the elimination of harmful agents from indoor air and to avoid producing harmful agents, while also generating less noise.

Description

[0001] DESCRIPTION

[0002] DEVICE AND METHOD FOR REMOVING VOLATILE ORGANIC COMPOUNDS AND MICROORGANISMS FROM INDOOR AIR

[0003] Field of the invention

[0004] The present invention is applicable in the field of air purification. In particular, the invention relates to a device and method for air treatment to eliminate volatile organic compounds and microorganisms in indoor air.

[0005] Background of the invention

[0006] Air can carry a variety of harmful pollutants, such as microorganisms, which cause airborne diseases; allergens; and volatile organic compounds (VOCs); as well as biological or chemical particles, for example, from biomedical waste handled in medical facilities, laboratories, etc.

[0007] The control and elimination of these pollutants in indoor air is typically achieved through the use of filters in heating and air conditioning ventilation systems, such as high-efficiency particulate air (HEPA) filters. HEPA filters can prevent the spread of bacteria and viruses through the air, for example, in biomedical applications, and therefore prevent infections from occurring in these premises. The highest-rated HEPA filters have an efficiency of 99.995%, ensuring a high level of protection against airborne diseases. Particles are trapped in the fibers that make up these filters. However, microorganisms are not eliminated. On the contrary, they accumulate and form colonies on the filter, infecting and spreading diseases through the ventilation system.Furthermore, the use of HEPA filters in ventilation systems causes significant pressure drops, reducing their performance and efficiency. A well-known alternative solution for indoor air treatment involves the use of ultraviolet (UV) light emissions to eliminate bacteria in the air by exposing said air to a plurality of ultraviolet (UV) light lamps. Similarly, ultraviolet (UV) light lamps can be used to irradiate a titanium dioxide (TIO2) matrix, eliminating polluting particles present in the air as they pass through said irradiated matrix.

[0008] Another well-known alternative solution used for treating contaminated air is to expose it to a plasma discharge. However, as byproducts of this discharge, ozone (O3) and nitrogen oxide (NO) are generated, which are hazardous chemicals that are harmful to human health if they reach the indoor environment of the premises where the air treatment device or apparatus is located.

[0009] Air treatment devices are also known that combine the solutions described above, that is, first, they carry out a first stage of treatment of the contaminated air flow coming from a room with atmospheric plasma treatment means, where part of the volatile organic compounds (VOCs) and microorganisms contained in the air flow are eliminated and, then, a second stage of treatment of said air flow is carried out in photocatalysis treatment means, where the rest of the volatile organic compounds (VOCs) and microorganisms contained in the air flow are eliminated, as well as the by-products of the plasma discharged in the plasma treatment means, which are carried away by said air flow.

[0010] All of these known solutions have the disadvantage of requiring powerful propulsion systems capable of inducing the airflow to be treated along the airflow path formed in the device, which passes through the atmospheric plasma treatment systems and the photocatalytic treatment systems. These mechanical propulsion systems, such as fans or compressors, represent a high energy consumption in addition to that required for the operation of both air treatment systems and also generate undesirable noise. These systems rely exclusively on the use of chemical agents and ozone-generating elements to achieve their effectiveness.

[0011] Summary description of the invention

[0012] The present invention solves the aforementioned drawbacks by means of, according to a first aspect, a device for removing volatile organic compounds and microorganisms from indoor air, according to independent claim 1. According to a second aspect, the invention relates to a method for removing volatile organic compounds and microorganisms from indoor air, which makes use of the above device, according to independent claim 12. Other optional advantageous features are described in the preferred embodiment and in the independent claims.

[0013] The present invention eliminates harmful environmental agents such as bacteria, viruses and other pathogens, biological or chemical particles, and so on, in an optimized manner, thanks to the combined application of three technologies (silicon dioxide coating, photocatalytic oxidation, and needle-tip bipolar ionization) in three chambers.

[0014] This technology aims to optimize the elimination of harmful agents without producing byproducts that are harmful to health. It uses so-called "low-noise" equipment, generally below 40 dB, and often even below 30 dB. This equipment makes up for the shortcomings of the aforementioned and existing technologies through the application of innovation and technology.

[0015] Brief description of the figures

[0016] The above and other advantages and features will be more fully understood from the following detailed description of an exemplary embodiment, with reference to the following figures 1-2, which should be considered in an illustrative and non-limiting manner.

[0017] Figure 1 shows a schematic plan view of the removal device of the present invention.

[0018] Figure 2 shows an enlarged schematic view, in detail, of Figure 1.

[0019] List of references

[0020] 1 Housing

[0021] 2 First chamber

[0022] 3 Second chamber

[0023] 4 Third chamber

[0024] 5 Fan

[0025] 6 Blades

[0026] 7 Obstacles (VERTICAL)

[0027] 8 Lamps (HORIZONTAL)

[0028] 9 Accommodations (HORIZONTAL)

[0029] 10 metallic threads

[0030] 11 Walls

[0031] Detailed description of the invention

[0032] The following provides, with the aid of the attached figures 1-2 referred to above, a detailed description of a preferred embodiment of a device and a method for eliminating volatile organic compounds and microorganisms in indoor air, object of the present invention.

[0033] The device comprises a housing (1), which houses the rest of the components, and which allows easy installation in homes, commercial premises, hospitality establishments, hospital facilities, etc. Inside the housing (1), there are three chambers (2, 3, 4). Of the three chambers (2, 3, 4), a first chamber (2) includes a fan (5), preferably low noise, which has blades (6) coated with silicon dioxide nanocrystals (SÍO2). The fan (5) described performs a double function: on the one hand, to force the entry of contaminated air into the interior of the device - in particular, the housing (1) -, to capture and, therefore, remove, said contaminated air and, on the other hand, act as a first route of elimination of unwanted compounds (volatile organic compounds and microorganisms), by means of silicon dioxide.

[0034] In the first chamber (2), an initial elimination of harmful agents, both chemical and biological, occurs through the silicon dioxide nanocrystals, by means of combined mechanical and chemical action, instead of the traditional purely chemical elimination. Silicon dioxide is modified to acquire antimicrobial properties, for which reason it is called "functionalized silicon dioxide", to which a coating of an antimicrobial compound is adhered, such as quaternary ammoniums and functionally equivalent compounds, whose operation is explained below.

[0035] SiO2 nanocrystals can form an ultrathin coating on surfaces, creating a nearly invisible protective barrier. Although pure SiO2 is not antimicrobial, its structure allows other agents to adhere to its surface. Therefore, if SiO2 nanocrystals are modified with adhering antimicrobial compounds, they can act as a hostile surface for microorganisms.

[0036] When SiO2 nanocrystals are functionalized, in the manner just indicated, with quaternary ammonium type groups or other molecules with positively charged nitrogen, an electrostatic attraction is created by the positive charge of nitrogen towards the negatively charged cell membranes of microorganisms, which leads the microorganisms to impact against the silicon dioxide nanocrystals, so that the nanocrystals perforate the cell membrane of microorganisms, interrupting the lipid bilayer and causing cell lysis, which destroys the microorganisms.

[0037] The functionalization of silicon dioxide crystals with positive nitrogen compounds, as just explained, presents the following advantages:

[0038] - Long-lasting effect: Unlike liquid disinfectants, a coating functionalized with SiO2 nanocrystals can remain active for long periods.

[0039] - No reactivation required: Works without UV light or external agents.

[0040] - Broad spectrum: Can act against bacteria, fungi and some viruses.

[0041] - It is not mutagenic, unlike other substances, such as Triclosan.

[0042] The fan (5) moves the contaminated air towards a second chamber (3) that contains obstacles (7) to create turbulences in the contaminated air flow. The obstacles (7) are impregnated with silicon dioxide nanocrystals (SIO2), with fungicidal, antibacterial and antiviral capacity, by means of the coating described above. The obstacles (7) can be materialized in tubes - generally cylindrical - made of metal, preferably arranged vertically. The turbulences extend the contact of the contaminated air with the silicon dioxide, resulting in a double effect: on the one hand, it increases the residence period of the microorganisms in the second chamber (3) and, therefore, the chances of being neutralized by the silicon dioxide nanocrystals and ultraviolet light, while, on the other hand, the turbulence facilitates the aforementioned electrostatic attraction between the silicon dioxide nanocrystals and the microorganisms.

[0043] The choice of nanocrystals for silicon dioxide coatings allows for high adhesion and integration with the coated substrate, without interfering with its function, and invisibly.

[0044] The second chamber (3) also includes ultraviolet light lamps (8) with germicidal capacity. The lamps (8) are preferably supported in housings (9) translucent to ultraviolet light, for example, made of quartz or borosilicate, which may be tubular in shape, according to the lamps. The lamps (8) and, where appropriate, the housings (9), may be distributed transversally through the second chamber (3). The device may further include control means (not shown), for example, housed in the housing (1), for controlling the operation of the lamps (8), for example, by adapting operating characteristics of the lamps (8), such as voltage. The control means may be configured to additionally control the operation of the fan (5), for example, the intensity of the fan (5).Furthermore, the control means may include sensors (not shown) for detecting and, preferably, quantifying predetermined particular compounds, such as: humidity; temperature; formaldehyde; airborne particles of maximum dimensions, in microns, equal to or greater than a predetermined value, such as PM 1.0, PM 2.5, PM 4.0, PM 10.0); total volatile organic compounds (TVOC), ozone (O3), and NO2.

[0045] The control means may additionally include one or more CO2 concentration meters (not shown), indicators of the concentration of microorganisms. The control means may be configured to, based on the measurements of the sensors and the concentration meters, command the voltage of the lamps (8) and / or the intensity of the fan (5) based on the measurements. The determination of the microorganism concentrations from the CO2 measurements and, where appropriate, the control of the voltage of the lamps (8) and / or the intensity of the fan (5), can be carried out, according to a preferred embodiment, through artificial intelligence techniques, such as machine learning and deep learning.

[0046] Interspersed between the housings (9) for the lamps (8), there is, crossing the second chamber (3), preferably horizontally, such that from side to side, a network of metallic threads (10), especially of noble metals, such as gold, silver, platinum, etc., to provide a germicidal effect.

[0047] In the second chamber (3), the housings (9) of the lamps (8) and / or the walls (11) of the interior of the second chamber (3) itself and / or the metal wires (10), are impregnated with a photocatalytic solution, for example, based on titanium dioxide, which may be complemented with one or more additional catalysts, with the purpose of producing a photocatalytic oxidation. At the exit of the second chamber (3), there is a third chamber (4), towards which the contaminated air is transferred from the second chamber (3), and which houses a needle-tip bipolar air ionization system, free of ozone (not shown) which, in addition to eliminating the harmful agents that remain (chemical and biological), by ionizing the resulting air, charges the air with ions, sanitizing the surfaces where they are deposited, before expelling purified air to the outside of the device, in particular, from the housing (1).In this way, the ions in the expelled air disinfect the surfaces on which they land, as well as neutralize biological agents (microorganisms, bacteria) and VOCs (volatile organic compounds) upon impact. This system, and its associated operating procedure, guarantees the elimination of harmful environmental agents (chemical agents, biological agents, viruses).

Claims

CLAIMS 1.- Device for eliminating volatile organic compounds and microorganisms in indoor air, characterized in that it comprises: - a housing (1), housing: a first chamber (2); a second chamber (3), following the first chamber (2); and a third chamber (4), following the second (3) chamber; - a fan (5), housed in the first chamber (2), to capture contaminated air, and comprising blades (6) coated with silicon dioxide nano-crystals (SIO2), in turn coated with an antimicrobial compound with positively charged nitrogen, to electrostatically attract and destroy microorganisms; - obstacles (7) located in the second chamber (3), to create turbulence in the contaminated air received from the first chamber (2), and which are impregnated with silicon dioxide nano-crystals (SIO2), in turn coated with an antimicrobial compound with positively charged nitrogen, to electrostatically attract and destroy microorganisms; - ultraviolet light lamps (8) located in the second chamber (3); - a photocatalytic solution impregnating interior walls (11) of the second chamber (3); and - a needle-tip bipolar air ionization system, free of ozone, located in the third chamber (4), from which purified air is expelled. 2.- Device, according to claim 1, where the obstacles (7) are materialized in metal tubes, preferably arranged vertically.

3. Device according to any of claims 1-2, which additionally comprises housings (9) for supporting the lamps (8) of the second chamber (3), which are translucent to ultraviolet light, 4.- Device, according to claim 3, where the housings (9) are distributed across the second chamber (3) in a transverse manner. 5.- Device according to any of claims 3-4, further comprising a network of metal wires (10), interspersed between the housings (9) for the lamps (8). 6.- Device, according to claim 5, where the metallic threads (10) of the net are arranged crossing the second chamber (3) horizontally. 7.- Device according to any of claims 5-6, wherein the metal wires (10) are made of noble metals. 8.- Device according to any of claims 1-7, wherein the fan (5) is a fan (5) with a noise level of less than 40 dB. 9.- Device according to any of claims 1-8, further comprising control means for controlling the operation of the lamps (8) and / or the fan (5). 10.- Device, according to claim 9, where the control means comprise: - at least one sensor to detect the presence and, where appropriate, the concentration of predetermined compounds, and - one or more CO2 concentration meters to estimate the concentration of microorganisms, the control means being configured to control the operation of the fan (5) and / or the lamps (8) from the sensors and the CO2 meter or meters. 11.- Device, according to claim 10, wherein the at least one sensor is selected from one or more of the following: - humidity sensor; - temperature sensor; formaldehyde sensor; - airborne particle sensor with maximum dimensions equal to or greater than a predetermined value; - total volatile organic compounds (TVOC) - ozone (O3), and - NO2. 12.- Device according to any of claims 1-11, wherein the housings (9) of the lamps, and / or the metal wires (10), are also impregnated by the photocatalytic solution. 13.- Device according to any of claims 1-12, wherein the photocatalytic solution comprises one or more catalysts that include titanium dioxide. 14.- Device according to any of claims 1-13, wherein the antimicrobial compound with positively charged nitrogen comprises quaternary ammoniums. 15.- Method for eliminating volatile organic compounds and microorganisms in indoor air, which uses the device described in any of claims 1-14, characterized in that it comprises: - forcing an introduction of contaminated air into the housing (1) through the fans (5) of the first chamber (2); - treating the contaminated air by means of the silicon dioxide nano-crystals that cover the blades (6) of the fan (5), such that the positively charged nitrogen of the antimicrobial compound that covers the silicon dioxide nano-crystals attracts the cytoplasmic membranes of the microorganisms, which are negatively charged, such that the membranes impact against the silicon dioxide nano-crystals, which tear said membranes, destroying the microorganisms; - transferring the contaminated air from the first chamber (2) to the second chamber (3), so that the silicon dioxide nano-crystals attract the microorganisms, the microorganisms impacting against the silicon dioxide nano-crystals, which tear the cytoplasmic membranes of the microorganisms; - causing turbulence in the contaminated air of the second chamber (3) by means of the obstacles (7); - treating the contaminated air from the second chamber (3) by means of silicon dioxide nano-crystals impregnating the obstacles (7); - treating the contaminated air in the second chamber (3) with ultraviolet light from the lamps (8); - treating the contaminated air in the second chamber (3) with the photocatalytic solution; - transfer the contaminated air from the second chamber (3) to the third chamber (4); and - treat the contaminated air in the third chamber (4) with the ozone-free needle-tip bipolar air ionization system. 16.- Method according to claim 15, where the turbulence caused by the obstacles (7), on the one hand, increases the residence period of the microorganisms in the second chamber (3) and, on the other hand, facilitates the electrostatic attraction between the silicon dioxide nano-crystals and the microorganisms. 17.- Method according to any of claims 15-16, which additionally includes controlling the lamps (8), varying some of their characteristics, such as voltage. 18.- Method according to any of claims 16 and 17, which includes controlling the fan (5) by varying some of its characteristics, such as power. 19.- Method according to any of claims 17 and 18, wherein the controlling step includes: - take measurements with the sensors for predetermined compounds, and with the CO2 concentration meter; - determine, from the measurements, the presence and, where appropriate, the concentration of the predetermined compounds, as well as the concentration of CO2: and modify the operation of the fan (5) and / or the lamps (8) based on the concentration of the predetermined compounds and the concentration of CO2. 20.- Method, according to claim 19, where the modification of the operation of the fan (5) and / or the lamps (8) based on the concentrations comprises the use of artificial intelligence techniques, such as machine learning and deep learning.

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