A device for treating a gas stream comprising at least one support for a liquid medium in which microorganisms or microparticles are present.

Abstract

A gas stream treatment device comprising at least one support of a liquid medium in which microorganisms or microparticles are present. The invention relates to a device comprising at least one support (12) configured to support at least one liquid medium offering at least one exchange surface (F12) against which flows a gas stream to be treated containing elements to be removed, the liquid medium containing microorganisms or microparticles chosen to interact with the elements to be removed present in the gas stream in order to transfer them from the gas stream to the liquid medium.According to the invention, each support (12) comprises a plurality of reservoirs (46), each delimited by at least two walls (36, 38) spaced at a distance configured to obtain the largest possible exchange surface (F12) between the liquid medium and the gas flow through a surface tension phenomenon between the walls (36, 38) and the liquid medium. Figure 7.

Description

Title of the invention: Device for treating a gas flow comprising at least one support of a liquid medium in which microorganisms or microparticles are present

[0001] The present application relates to a device for treating a gas flow comprising at least one support for a liquid medium in which microorganisms or microparticles are present.

[0002] Over the ages, photosynthetic and mineralizing activities had stabilized the Earth's atmosphere at a carbon dioxide level of 350 ppm (parts per million) and an oxygen level of 20.95%.

[0003] Since the beginning of the industrial era, the level of carbon dioxide in the Earth's atmosphere has continued to increase and now reaches 400 ppm. This increase in the level of carbon dioxide results in an inexorable increase in the average temperature of the Earth's atmosphere and climate change.

[0004] At the same time, air quality is deteriorating in cities, in professional environments and in transport zones where gases toxic to humans and the presence of fine particles can affect their health.

[0005] Therefore, solutions are being sought to reduce emissions of fine particles, nitrogen oxide and carbon dioxide and to capture some of these elements present in the Earth's atmosphere.

[0006] Naturally, forests and oceans contribute to the capture of carbon dioxide. Thus, forests allow, through photosynthesis, to capture and store part of the carbon dioxide emitted while producing oxygen. Unfortunately, deforestation, particularly linked to the expansion of agricultural land, contributes to reducing the capture of carbon dioxide by forests and to increasing the carbon dioxide level because most of the vegetation and wood cut during deforestation is burned.

[0007] Microorganisms in the oceans contribute to capturing and mineralizing carbon dioxide, accounting for 40% of our emissions. This rate is difficult to increase because it would lead to acidification of the oceans, unbalancing the aquatic environment and, ultimately, a disaster for biodiversity.

[0008] Technical solutions have been developed to reduce the level of carbon dioxide in the Earth's atmosphere. One of these consists of trapping carbon dioxide in gaseous form, called supercritical, in sealed underground pockets. This solution is not satisfactory because non-basaltic reservoirs do not allow rapid mineralization of carbon dioxide, which then takes place over several hundreds of years. If the rock cracks, the gas can rise and cause an ecological disaster.

[0009] Another solution is to inject carbon dioxide in the presence of water into basalt rocks in order to reduce the mineralization cycle to a few years. This solution is not entirely satisfactory because it requires 20 times more water than carbon dioxide and basalt rocks only constitute 10% of the Earth's crust.

[0010] Other solutions propose, like the oceans, to use micro-organisms in aquatic environments, outside the oceans, to capture carbon dioxide.

[0011] Thus, the holder of the present application has developed solutions described in particular in documents FR2923287, FR2945215 and FR3096677 for several years.

[0012] According to the first two documents, a carbon dioxide capture device comprises a reservoir containing a liquid medium in which microorganisms develop as well as an artificial light energy source positioned appropriately relative to the liquid medium to promote the development of the microorganisms. The reservoir is configured to promote exchanges between the liquid medium and the gaseous medium containing the carbon dioxide to be captured. According to these first two documents, the microorganisms are of the autotrophic type and generate calcified elements from the carbon dioxide. These autotrophic microorganisms having a very low biomass productivity and therefore a limited capacity to fix carbon dioxide, it is necessary to increase their number and consequently to provide more numerous and larger reservoirs.

[0013] Document FR3096677 proposes a device for treating gaseous and liquid effluents using particular micro-organisms capable of purifying water of organic matter and air by fixing carbon dioxide.

[0014] According to this document FR3096677, the device comprises a treatment enclosure containing a liquid medium in which the microorganisms develop, said treatment enclosure comprising an inlet for liquid to be treated, an outlet for the purified liquid, an inlet for gaseous effluent to be treated and an outlet for the purified gaseous effluent.

[0015] According to a first embodiment, the gaseous effluent to be treated is introduced by bubbling into the liquid medium containing the microorganisms.

[0016] According to another embodiment, the device comprises at least one porous support in the open air, in contact with the air or the gaseous effluent to be treated, as well as a supply system configured to cause a liquid to be treated to flow onto the support(s). This porous support generally has opening cavities of diameter less than 2 mm. According to this other embodiment, the microorganisms may be present in the liquid to be treated or immobilized on the porous support(s) kept moist by the passage of the liquid to be treated containing organic matter. The porous supports make it possible to increase the surface area of ​​the liquid in contact with the air or the gaseous effluent to be treated.

[0017] The treatment device described in document FR3096677 is not fully satisfactory because it requires a large volume of liquids to be treated flowing over the porous supports and therefore a large reservoir under the porous supports. This large volume of liquids to be treated and circulated requires a costly and energy-intensive hydraulic installation. According to another disadvantage, the porous supports tend to become clogged and lose their effectiveness.

[0018] Furthermore, whatever the embodiment described in documents FR2923287, FR2945215 and FR3096677, the carbon dioxide capture device requires a large volume of liquid, which leads to a significant increase in its mass, making it difficult to install the devices at height, for example.

[0019] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0020] For this purpose, the invention relates to a device comprising at least one support configured to support at least one liquid medium offering at least one exchange surface against which a gas flow to be treated flows, containing elements to be removed, the liquid medium containing microorganisms or microparticles chosen to interact with the elements to be removed present in the gas flow in order to transfer them from the gas flow to the liquid medium.

[0021] According to the invention, each support comprises a plurality of reservoirs, each delimited by at least two walls spaced apart by a distance configured to obtain the largest possible exchange surface between the liquid medium and the gas flow thanks to a phenomenon of surface tension between the walls and the liquid medium.

[0022] This solution allows the liquid medium to be maintained on a support with at least the largest possible exchange surface thanks to a surface tension phenomenon while limiting fouling of the support.

[0023] Other characteristics and advantages will emerge from the description of the invention which follows, a description given by way of example only, with reference to the appended drawings, among which:

[0024] [Fig. 1] is a schematic representation of an air treatment device illustrating a simplified embodiment of the invention,

[0025] [Fig.2] is a schematic representation of an air treatment device illustrating another simplified embodiment of the invention,

[0026] [Fig.3] is a schematic representation of an air treatment device illustrating an embodiment of the invention,

[0027] [Fig.4] is a perspective view of a liquid support illustrating a mode of rea lization of the invention,

[0028] [Fig.5] is a front view of the liquid support visible in [Fig.4],

[0029] [Fig.6] is a section along line VI-VI of [Fig.5],

[0030] [Fig.7] is an enlarged cross-section of the liquid carrier visible in [Fig.4],

[0031] [Fig.8] is a perspective view of a liquid support illustrating a mode of rea lization of the invention,

[0032] [Fig.9] is a front view of the liquid support visible in [Fig.8],

[0033] [Fig. 10] is a section along line XX of [Fig.9],

[0034] [Fig. 11] is an enlarged cross-section of the liquid carrier visible in [Fig.8],

[0035] [Fig. 12] is a perspective view of a liquid support illustrating a mode of rea lization of the invention,

[0036] [Fig.13] is a side view of the liquid holder visible in [Fig.12], and

[0037] [Fig. 14] is a schematic representation of an air treatment device illustrating an embodiment of the invention.

[0038] According to embodiments visible in Figures 1 to 3, an air treatment device 10 comprises at least one support 12 configured to support at least one liquid medium M (visible in Figures 7, 11, 13) which has at least one exchange surface F12 against which at least one gas flow 14 to be treated containing carbon dioxide flows.

[0039] Each liquid medium M contains microorganisms or microparticles. For example, the liquid medium M is water configured to allow microorganisms to develop. According to one configuration, the microorganisms are chosen to capture the carbon dioxide present in the gas flow 14 and to release oxygen into this gas flow 14 when the latter flows against the exchange surface(s) F12, F12'. Thus, when the gas flow 14 flows against the exchange face(s) F12, F12', it becomes depleted in carbon dioxide and enriched in oxygen.

[0040] The microorganisms used, which colonize each liquid medium M, are photosynthetic microorganisms capable of capturing and sequestering carbon dioxide. According to one configuration, each support 12 can be made of a material comprising fillers, such as calcium for example, to promote the mineralization of carbon dioxide by certain microorganisms.

[0041] According to one embodiment, the microorganisms are chosen from freshwater or marine microalgae, cyanobacteria, bacteria including photosynthetic bacteria, chemotrophic bacteria, chemolithoautotrophic or pi- bacteria cocyanobacteria as well as protists, proteobacteria and archaea.

[0042] Of course, the invention is not limited to microorganisms. Thus, the liquid medium M may comprise microorganisms or microparticles configured to interact with elements present in the gas flow 14 to be removed from the latter in order to transfer them from the gas flow 14 to the liquid medium M.

[0043] According to an embodiment visible in [Fig.2], the air treatment device 10 comprises a support 12 which has a single face, substantially vertical, against which a gas flow 14 to be treated flows.

[0044] According to an embodiment visible in [Fig.l], the air treatment device 10 comprises an enclosure 16 having at least one wall 18 delimiting an interior zone ZI and an exterior zone ZE as well as a support 12, positioned in the interior zone of the enclosure 16, which has two substantially vertical faces, parallel to each other and spaced from the enclosure 16. The enclosure 16 comprises at least one inlet 20 configured to allow a gas flow 14 to be treated to enter the enclosure 16 as well as at least one outlet 22 configured to allow a gas flow 14' to exit the enclosure 16, the support 12 and the enclosure 16 being configured to allow the gas flow 14 which enters the enclosure 16 via the inlet 20 to flow against the two faces of the support 12 and then to exit the enclosure 16 via the outlet 22.Positioning the support(s) 12 in an enclosure 16 makes it possible to better regulate the flow of air in contact with the support(s) 12.

[0045] According to another embodiment visible in [Fig. 3], the air treatment device 10 comprises an enclosure 16 having at least one wall 18 delimiting an interior zone ZI and an exterior zone ZE as well as several supports 12 positioned in the interior zone of the enclosure 16, each support 12 having two substantially vertical faces, the faces of the different supports 12 being parallel and spaced apart from each other and spaced apart from the enclosure 16. The enclosure 16 comprises at least one inlet 20 configured to allow a gas flow 14 to be treated to enter the enclosure 16 as well as at least one outlet 22 configured to allow a gas flow 14' to exit the enclosure 16, the supports 12 and the enclosure 16 being configured to allow the gas flow 14 which enters the enclosure 16 via the inlet 20 to flow against the faces of at least a support 12 and exit the enclosure 16 via the output 22.According to one arrangement, the supports 12 are arranged in a staggered manner to allow the gas flow 14 which enters the enclosure 16 via the inlet 20 to flow against all the faces of all the supports 12 before exiting the enclosure 16.

[0046] The inlets and outlets 20 and 22 are positioned so as to increase the path traveled by the gas flow in contact with the supports 12.

[0047] According to an embodiment visible in [Fig. 3], the outlet 22 is provided with an insect screen. The air treatment device 10 comprises a pre-treatment system treatment 24 of the gas flow 14 entering the enclosure 16, configured to remove undesirable particles from the gas flow, and in particular to form a barrier to insects, and to block the metal particles and / or the undesirable particles in the enclosure 16. According to a non-limiting embodiment and given by way of example, the pretreatment system 24 comprises an insect screen 24.1, a foam filter 24.2, a magnetic filter 24.3 as well as a mechanical filter 24.4.

[0048] The gas flow can circulate between the inlet and outlet 20, 22 of the enclosure 16 in a natural manner.

[0049] According to one embodiment, the gas flow circulates between the inlet and outlet 20, 22 of the enclosure 16 in a forced manner. For this purpose, the air treatment device 10 comprises at least one flow generator 26 to force the gas flow to flow from the inlet 20 to the outlet 22. For example, the flow generator 26 is a pump.

[0050] According to one mode of operation, the flow generator 26 is configured so that the gas flow moves in the enclosure 16 in contact with the supports 12 with a speed less than or equal to approximately 10 m / s, preferably at a speed of the order of 4 to 6 m / s. This speed of movement contributes to optimizing the capture by the microorganisms of the carbon dioxide present in the gas flow circulating in contact with the support(s) 12.

[0051] According to one embodiment, the enclosure 16 may comprise at least one closable opening as well as a flap movable between a closed position in which it closes the opening and an open position in which it at least partially clears the opening, the flap and the opening being sized so as to allow the support(s) to pass through the opening, in particular one after the other. In addition, each support 12 is removable and connected directly or indirectly to the enclosure 16 by a removable connection.

[0052] Of course, the invention is not limited to the embodiments previously described. Other alternatives are conceivable.

[0053] Regardless of the configuration, the microorganisms must have light energy to capture carbon dioxide.

[0054] According to a first configuration visible in Figures 1 and 2, the air treatment device 10 does not include its own light energy source and uses a natural light energy source, such as the sun for example, or an artificial light energy source common to another function, such as lighting for example.

[0055] According to this first configuration, the air treatment device 10 may comprise at least one optical waveguide, passing through at least one wall 18 of the enclosure 16, configured to capture a light flux in the outer zone of the enclosure 16 and diffuse it in the inner zone of the enclosure 16 as close as possible to the microorganisms.

[0056] According to a second configuration visible in [Fig. 3], the air treatment device 10 comprises at least one light energy source 28. By way of example, the light energy source 28 comprises a set of light-emitting diodes.

[0057] According to this second configuration, the light energy source 28 can be positioned in the interior zone or the exterior zone of the enclosure 16. This light energy source 28 is connected to a power supply 28.1, located in the exterior zone of the enclosure 16, which may or may not be integrated into the air treatment device 10.

[0058] According to one embodiment, the light energy source 28 is separate from the support(s) 12 and is not integrated into the support(s) 12. In this case, the air treatment device 10 may comprise at least one optical waveguide configured to capture a light flux generated by the light energy source 28 and diffuse it as close as possible to the microorganisms present on the support(s) 12.

[0059] According to another embodiment, the light energy source 28 is positioned at least partially in a support 12.

[0060] According to other embodiments, the air treatment device 10 may comprise at least one light energy source 28 positioned outside the support(s) 12 and at least one light energy source 28 positioned at least partially in a support 12.

[0061] The fact of not placing the light energy source 28 at a distance from the support(s) 12, by placing it outside the enclosure 16 and by conveying the light flux using optical waveguides, makes it possible to limit the risks of damage or malfunction of the light energy source 28.

[0062] According to an embodiment visible in [Fig. 3], the air treatment device 10 comprises at least one light energy regulation system 28 configured to regulate at least one characteristic of the light energy supplied to the microorganisms, this characteristic being chosen in particular from the light intensity, the duration of exposure of the microorganisms to the light flux or the color temperature of the light flux. This list of characteristics is not exhaustive.

[0063] The wall(s) of the enclosure 16 may be opaque to facilitate the regulation of the light energy.

[0064] According to another characteristic of the invention, to promote the supply of light energy to the microorganisms, each support 12 is made of a material promoting the diffusion of a light flux. According to one embodiment, each support 12 is made of a transparent, translucent material or material adapted for the diffusion of light.

[0065] The air treatment device 10 comprises at least one air supply system liquid 30 configured to pour the liquid onto at least one support 12, in particular onto the top part of each support 12.

[0066] According to one embodiment, the liquid supply system 30 comprises at least one dripper 30.1 or any other means configured to supply a small quantity of liquid with a controlled flow rate and positioned above each support 12, at least one container 30.2 from which the supply liquid is taken as well as at least one conduit 30.3 connecting each dripper 30.1 to the container 30.2. The liquid supply system 30 may be configured to pour the liquid onto at least one of the supports, the liquid then trickling onto the other supports 12.

[0067] Preferably, the liquid supply system 30 comprises at least one collection tank 30.4, positioned in the lower part of the enclosure 16 and configured to collect any excess liquid, communicating with at least one container 30.2 from which the supply liquid is taken. This embodiment makes it possible to limit the consumption of liquid.

[0068] The collection tank 30.4 and the container 30.2 are connected by at least one conduit 30.5 and arranged so as to obtain a gravity flow between them.

[0069] The container 30.2 may be supplied by a source of liquid 32 external to the air treatment device 10 and comprise a system for regulating the level of liquid in the container 30.2, such as a float controlling the opening or closing of a valve 34 interposed between the source of liquid 32 and the container 30.2.

[0070] According to one embodiment, the liquid used in the air treatment device 10 is water, in particular demineralized water. Of course, the invention is not limited to this liquid. Other liquids are conceivable. Additives and / or components may be added to the water.

[0071] According to a first embodiment visible in Figures 4 to 7, each support 12 comprises a rigid structure which comprises a plurality of pairs of first and second walls 36, 38 superimposed in a vertical direction and slightly spaced apart so as to delimit superimposed reservoirs 46 for containing the liquid medium M colonized by microorganisms. Each wall 36, 38 has an upper face F36, F38 as well as a lower face F36', F38'.

[0072] By slightly spaced, it is meant that a liquid placed on the upper face F36 of a first wall 36 is in contact, thanks to a phenomenon of surface tension, with the lower face of a second wall 38 located just above the first wall 36, as illustrated in [Fig. 7]. This phenomenon of surface tension makes it possible to stretch the surface of the liquid medium M in contact with the gas flow 14. The maximum distance between the pairs of walls 36, 38 is determined in particular as a function of the characteristics of the liquid medium M such as the wettability of the liquid. This maximum distance between the first and second walls 36, 38 is configured to obtain a exchange surface between the liquid medium M and the gas flow 14 as large as possible regardless of the orientation of this exchange surface. The distance between the first and second walls 36, 38 must be as close as possible to this maximum distance to reduce the mass of the support 12.

[0073] To give an order of magnitude, when the liquid is water, the walls 36, 38 are spaced apart by a distance of the order of 6 mm.

[0074] According to the first embodiment, each support 12 comprises at least two uprights 40 substantially parallel to each other. At a minimum, the support 12 comprises two uprights 40. Generally, the support 12 comprises several regularly spaced uprights 40. By way of example and in a non-limiting manner, each upright 40 is in the form of a thin plate (of the order of 2 to 8 mm thick) which has a height of the order of 100 to 1000 mm and a width of the order of 10 to 100 mm.

[0075] According to the first embodiment, each wall 36, 38 is in the form of a blade, substantially rectangular in top view, which has first and second longitudinal edges 42.1, 42.2 (which correspond to the long sides) substantially parallel to each other as well as first and second ends 44.1, 44.2 connected to the uprights 40. The first longitudinal edges 42.1 of the different blades are positioned in the same vertical plane which forms the first face of the support 12 at the level of which the reservoirs 46 delimited by the walls 36, 38 open. The second longitudinal edges 42.2 of the different blades are positioned in the same vertical plane which forms the second face of the support 12 at the level of which the reservoirs 46 delimited by the walls 36, 38 open. According to one configuration, each wall 36, 38 has a width (distance between the first and second longitudinal edges 42.1, 42.2) substantially equal to that of amounts 40. .

[0076] For each wall 36, 38, the first and second longitudinal edges 42.1, 42.2 are located in a horizontal plane.

[0077] By way of example and in a non-limiting manner, each blade-shaped wall 36, 38 has a thickness of the order of 2 to 8 mm, a width of the order of 10 to 100 mm and a length (distance between the first and second ends 44.1, 44.2) of the order of 70 to 700 mm.

[0078] According to one configuration, each wall 36, 38 has a cross-section (in vertical planes perpendicular to the first and second longitudinal edges) that is constant between the first and second ends 44.1, 44.2. In transverse planes, each wall 36, 38 has a curved shape, the central portion being offset downwards relative to the first and second longitudinal edges 42.1, 42.2. Thus, each wall 36, 38 forms a channel capable of storing the liquid medium M colonized by the microorganisms or the microparticles. All the walls being curves, the spacing between two successive walls is substantially constant between the first and second longitudinal edges 42.1, 42.2. As illustrated in [Fig.7], the horizontal plane passing through the first and second longitudinal edges 42.1, 42.2 of a first wall 36 is offset upwards relative to the lowest point of the lower face F38' of a second wall 38. When a liquid medium M is present on the upper face F36 of the first wall 36, the surface of the liquid medium M does not remain flat but rises until it is in contact with the lower face F38' of the wall 38 located just above thanks to a surface tension phenomenon. This configuration makes it possible to increase the exchange surfaces F12, F12' between each liquid medium M and the gas flow 14 to be treated.

[0079] According to one configuration, the longitudinal edges 42.1, 42.2 have grooves 48 and / or the lower faces F36', F38' of the walls 36, 38 are partially textured to allow the liquid medium M to remain in contact with the support 12 thanks to a surface tension phenomenon and thus increase the exchange surface between the liquid medium M and the gas flow 14.

[0080] According to a second embodiment, the support 12 comprises a plurality of walls 36, 38 delimiting a multitude of reservoirs 46 also called cells.

[0081] According to a variant visible in figures 8 to 11, the reservoirs 46 are blind and open at a single face of the support 12. According to another variant, the reservoirs 46 are through-holes and open at each of their ends, at the two parallel faces of the support 12.

[0082] According to one configuration, each reservoir 46 has a hexagonal section delimited by six walls 36, 38. The reservoirs 46 are all identical. The walls 36, 38 delimiting the reservoirs 46 are separated, in a vertical direction, by a distance of the order of 6 mm.

[0083] According to a configuration visible in [Fig. 11], each reservoir 46 has a concave bottom 46.1, such as a pyramidal or approximately semi-spherical bottom 46.1 for example.

[0084] According to one arrangement, each reservoir 46 is inclined so that the bottom 46.1 is offset downwards relative to the opening end 46.2. Thus, a straight line passing through the center 01 of the bottom 46.1 and the center 02 of the opening end 46.2 forms with a straight line perpendicular to the exchange surface F12 an angle of the order of 2 to 7°.

[0085] For information purposes, the opening end 46.2 and the bottom 46.1 are separated by a distance of the order of 6 mm. The opening end 46.2 is delimited by sides, corresponding to the edges of the walls 36, 38, which form a hexagon inscribed in a circle with a diameter of the order of 6 mm.

[0086] According to another embodiment visible in figures 12 to 14, a support 112 has a substantially spherical shape. This support 112 comprises a plurality of radial walls 136 positioned in radial planes passing through an axis of revolution A1 12 and connected to each other by at least one element of revolution 140. According to one configuration, the support 112 comprises two elements of revolution 140 in the form of a tube at the two poles of the spherical shape and a median ring. Of course, the invention is not limited to these elements of revolution 140.

[0087] Each radial wall 136 comprises an outer edge 136.1 in an arc of a circle and a substantially rectilinear inner edge 136.2. The outer edges 136.1 of the different radial walls 136 are positioned on a sphere. The inner edges 136.2 of the different radial walls 136 are positioned on a cylinder. The radial walls 136 are regularly distributed around the axis of revolution A1 12. The inner edges 136.2 are spaced apart from each other by a distance of the order of 0.5 mm. The inner edges 136.1 are spaced apart from each other by a distance of the order of 10 mm. Each pair of radial walls 136 is such that the latter form between them a reservoir 146 configured to retain, whatever the orientation of the support 112, a liquid medium M thanks to a phenomenon of surface tension. This liquid medium M offers a first exchange surface F12 at the level of the outer edges 136.1 and possibly a second exchange surface F12' at the level of the inner edges 136.2. According to one arrangement, for each radial wall 136, the outer and inner edges 136.1, 136.2 are separated by a distance of between 3 and 30 mm.

[0088] Whatever the embodiment, each support 12, 112 has a plurality of reservoirs 46, 146 each delimited by at least two walls 36, 38, 136 spaced apart so as to contain, whatever the orientation of the support 12, 112, at least one liquid medium M thanks to a phenomenon of surface tension between the walls 36, 38, 136 and the liquid medium M. Thus, each support 12, 112 maintains at least one liquid medium M so as to form at least one exchange surface F12 between each liquid medium M and the gas flow 14. The maximum distance between the pairs of walls 36, 38, 136 is determined in particular as a function of the characteristics of the liquid medium M such as the wettability of the liquid. This distance between the first and second walls 36, 38, 136 is configured to obtain an exchange surface F12 between the liquid medium M and the gas flow 14 that is as large as possible regardless of the orientation of this exchange surface.The distance between the first and second walls 36, 38 must be as close as possible to this maximum distance to reduce the mass of the support 12.

[0089] For this purpose, the walls 36, 38, 136 are spaced apart by a maximum distance of between 2 and 10 mm, preferably of the order of 6 mm. If the spacing between two walls 36, 38, 136 is less than 2 mm as in a porous structure, the support 12 tends to become clogged. In addition, this leads to an increase in the mass and the cost of support 12. If the spacing between two walls 36, 38, 136 is greater than 10 mm, the liquid does not remain in the tank and flows out. Thus, this solution makes it possible to maintain a liquid medium M on a support 12, 112 regardless of the orientation of the support 12, 112 and this with the largest possible exchange surface F12 while limiting the risks of fouling.

[0090] An air treatment device 10 comprises at least one support 12, 112. Generally, the air treatment device 10 comprises several supports 12, 112 which are arranged in an orderly or disorderly manner. As illustrated in [Fig. 14], the supports 12, 112 are stacked on top of each other in an orderly or disorderly manner. Whatever the embodiment, the air treatment device 10 comprises at least one support 12, 112 which is not immersed in a liquid but supports or contains at least one liquid medium M in which microorganisms develop or microparticles are present, the liquid medium M offering the largest possible exchange surface with a gas flow 14 containing elements to be removed, such as carbon dioxide particles, nitrogen oxide particles or fine particles for example.The microorganisms and / or microparticles are chosen according to the elements to be removed from the gas flow and are configured to interact with said elements to be removed from the gas flow 14 in order to transfer them from the gas flow 14 to the liquid medium M.

[0091] According to one embodiment, the support 12, 112 is rigid.

[0092] To maintain the liquid in the reservoirs 46, each of them has a depth (dimension taken in a direction perpendicular to the exchange surface) greater than 3 mm, preferably of the order of 6 mm.

[0093] According to the variants, the reservoirs 46, 146 are blind and all open only from a single exchange surface F12 or are through and each open at the level of the first and second exchange faces F12, F12'.

[0094] The air treatment device 30 comprises at least one liquid supply system 30 configured to pour the liquid above the support(s) at a controlled flow rate. By trickling, the liquid supported by the support(s) 12, 112 is gradually renewed.

[0095] By adjusting the flow rate, it is possible to maintain each liquid medium supported by the support(s) 12 colonized by the microorganisms while renewing the latter sufficiently to prevent fouling of the support 12, 112.

[0096] According to an embodiment visible in [Fig. 14], the air treatment device 10 comprises a translucent enclosure 116 in which a multitude of supports 112 are positioned, the enclosure 116 comprising an opening 116.1 in the upper part and a lower wall 116.2 permeable to the liquid. By way of example, the enclosure 116 has a cylindrical side wall 116.3. The air treatment device 10 comprises a liquid supply system 130 which comprises at least one dripper 130.1 or any other means configured to supply a small quantity of liquid with a controlled flow rate and positioned above the enclosure 116, at least one container 130.2 positioned under the enclosure 116 and in which the liquid from the enclosure 116 flows as well as at least one conduit 130.3 connecting each dripper 130.1 to the container 130.2. According to one configuration, the liquid supply system 130 comprises a closed circuit. The container 130.2 makes it possible to collect the elements removed from the gas flow 14.

[0097] The air treatment device 30 comprises a system for guiding the air to be treated through the enclosure 116. According to one embodiment, the air treatment device 30 comprises an air injection system 132 positioned under the enclosure 116, such as a bubbling system immersed in the liquid contained in the reservoir 130.2 for example. According to this embodiment, the gas flow 14 to be treated is introduced into the enclosure 116 via its lower wall 116.2 and the treated gas flow 14' leaves the enclosure 116 via its opening 116.1. According to this embodiment, a first means of capturing carbon dioxide by dissolution during bubbling is obtained as well as a second means of capturing by absorption thanks to the exchanges between the gas flow and the liquid medium M supported by each support 12.

[0098] In the presence of microorganisms, the air treatment device 10 comprises a light energy source 128.

[0099] Of course, the invention is not limited to these embodiments for the enclosure 16, 116, the liquid supply system 130 and / or the system for channeling the gas flow to be treated in the enclosure 16, 116 and bringing it into contact with the exchange surface of the liquid media M supported by the supports 12, 112.

Claims

Claims

1. Air treatment device comprising at least one support (12, 112) configured to support at least one liquid medium (M) offering at least one exchange surface (F12) against which a gas flow to be treated flows which contains elements to be removed, the liquid medium (M) containing microorganisms or microparticles chosen to interact with the elements to be removed present in the gas flow (14) in order to transfer them from the gas flow (14) to the liquid medium (M); characterized in that each support (12, 112) comprises a plurality of reservoirs (46, 146) each delimited by at least two walls (36, 38, 136) spaced apart by a distance configured to obtain the largest possible exchange surface (F 12) between the liquid medium (M) and the gas flow (14) thanks to a phenomenon of surface tension between the walls (36, 38, 136) and the liquid medium (M).

2. Air treatment device according to claim 1, characterized in that each reservoir (46, 146) has a depth greater than 3 mm, preferably of the order of 6 mm.

3. Air treatment device according to claim 1 or 2, characterized in that each reservoir (46, 146) is through and opens at the level of first and second exchange faces (F12, F12').

4. Air treatment device according to the preceding claim, characterized in that each support (12) comprises a plurality of pairs of first and second walls (36, 38) superimposed and slightly spaced apart so as to delimit the reservoirs, each wall (36, 38) being in the form of a blade which has first and second longitudinal edges (42.1, 42.2) substantially parallel to each other and positioned in a horizontal plane, the first longitudinal edges (42.1) of the different blades being positioned in the same vertical plane, the second longitudinal edges (42.2) of the different blades being positioned in the same vertical plane.

5. Air treatment device according to the preceding claim, characterized in that each blade-shaped wall (36, 38) has a thickness of the order of 2 to 8 mm, a width of the order of 10 to 100 mm and a length of the order of 70 to 700 mm.

6. Air treatment device according to one of claims 4 to 5, characterized in that each wall (36, 38) has a curved shape with a central portion offset downwards relative to the first and second longitudinal edges (42.1, 42.2).

7. Air treatment device according to one of claims 4 to 6, characterized in that the longitudinal edges (42.1, 42.2) have grooves (48) and / or the walls (36, 38) have lower faces (F36', F38') partially textured to allow the liquid to remain in contact with the support (12) thanks to a surface tension phenomenon.

8. Air treatment device according to claim 1 or 2, characterized in that the reservoirs (46) are blind and open at a single exchange surface (12).

9. Air treatment device according to the preceding claim, characterized in that each reservoir (46) comprises a concave bottom (46.1).

10. Air treatment device according to one of claims 8 to 9, characterized in that each reservoir (46) comprises an opening end (46.2) and a bottom (46.1) separated by a distance of the order of 6 mm.

11. Air treatment device according to the preceding claim, characterized in that each tank (46) is inclined so that the bottom (46.1) is offset downwards relative to the opening end (46.2).

12. Air treatment device according to one of claims 8 to 11, characterized in that each reservoir (46) has a hexagonal section delimited by six walls (36, 38) separated, in a vertical direction, by a distance of the order of 6 mm.

13. Air treatment device according to one of claims 1 to 3, characterized in that each support (112) comprises a plurality of radial walls (136) positioned in radial planes passing through an axis of revolution (Al 12) and connected to each other by at least one element of revolution (140).

14. Air treatment device according to the preceding claim, characterized in that each radial wall (136) comprises an outer edge (136.1) in an arc of a circle, the outer edges (136.1) of all the radial walls (136) being positioned on a sphere.

15. Air treatment device according to the preceding claim, characterized in that each radial wall (136) comprises a substantially rectilinear inner edge (136.2), the inner edges (136.2) of all radial walls (136) being positioned on a cylinder.

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