INSTALLATION FOR THE PRODUCTION AND PROCESSING OF GAS FLOW THROUGH A VOLUME OF LIQUID

Description

technical field

[0001] The present invention relates to the production and treatment of gas streams through a volume of liquid. It has applications in various fields such as, for example, and not limited to, heat recovery from a gas stream, particularly from hot air or industrial fumes; the production of a gas stream that is heated or cooled by passing through said volume of liquid; the production of a gas stream with controlled temperature and / or controlled absolute humidity; the humidification or dehumidification of a gas stream; the purification or filtration of a gas stream; the heating or air conditioning of industrial, commercial, or domestic premises or buildings; and the control of humidity in industrial, commercial, or domestic premises or buildings. Previous art

[0002] The use of a liquid, such as water, to treat, and in particular to heat or cool, a gas stream through heat exchange between the liquid and the gas stream, with direct contact between the two, is a long-established technique that has the advantage of being environmentally friendly, as it avoids the use of heat transfer fluids such as refrigerants. Heating or cooling the gas stream, and especially an air stream, can, for example, aim to produce a gas stream with a controlled temperature and / or a gas stream with a controlled absolute humidity.

[0003] One known solution for implementing this technique involves passing the gas stream through a curtain of fine droplets of the liquid, or through a gas-permeable exchange surface containing the liquid, such as a water-soaked textile, or circulating the gas stream in contact with moistened plates. The main drawback of this type of solution lies in the very low energy efficiency of the heat exchange between the liquid and the gas stream, and in the low airflow rates that can be achieved.

[0004] A second known solution involves passing the gas flow, and in particular the air flow, directly through a volume of liquid contained in a heat exchange chamber, by injecting the air flow into the liquid volume below its surface. This type of solution is described, for example, in international patent application WO 2006 / 138287 and in US patent US 4,697,735 ( figure 3 This type of solution is also described in international patent application WO2016 / 071648, which discloses the implementation of a heat exchange chamber open at the bottom and immersed in a volume of liquid. This second technical solution has the advantage of achieving a higher energy efficiency for heat exchange between the liquid and the gas stream than the first technical solution.

[0005] In this second technical solution, for a given gas flow rate, the efficiency of heat transfer between the gas and the liquid depends on the volume of liquid through which the gas flows in the device's heat exchange chamber. In practice, this means that the higher the gas flow rate, the larger the horizontal cross-section of this chamber must be to maintain heat transfer efficiency. Thus, when implementing, for example, a device of the type described in the aforementioned international patent application WO2016 / 071648, increasing the gas flow rate necessitates increasing one of the transverse dimensions of the heat exchange chamber, which in practice leads to a detrimental increase in the device's overall size.Furthermore, and most importantly, it was observed that beyond a certain gas flow rate, increasing the volume of liquid in the heat exchange chamber did not maintain the efficiency of heat transfer between the gas flow and the volume of liquid through which the gas flow passed in the heat exchange chamber, primarily due to the loss of edge effect efficiency through the walls of the heat exchange chamber. This type of device is therefore limited in terms of gas flow rate.

[0006] Document JP 2002 357333 A shows an installation according to the preamble of claim 1. Objective of the invention

[0007] One objective of the invention is to propose a new, simple technical solution enabling the production of treated gas flows through a liquid at a high flow rate. Summary of the invention

[0008] The invention thus relates to an installation for the production and processing of a gaseous stream according to claim 1.

[0009] More specifically, but optionally according to the invention, the installation may include the following additional and optional technical features, taken individually or in combination: The discharge openings of the injection ducts are all positioned at approximately the same depth relative to the surface of the initial volume of liquid contained in each heat exchange chamber when the air handling system is off. The initial volumes of liquid in all the heat exchange chambers are identical. The air handling system includes a fan or compressor connected to all the discharge openings of the heat exchange chambers or connected to all the inlet openings of the injection ducts.It includes a liquid reservoir, and the lower part of each exchange enclosure has at least one liquid inlet opening and is immersed in the same liquid bath (L) contained in said reservoir, such that when the air handling means are stopped, the lower part of each exchange enclosure contains an initial volume of this liquid, with an initial level (Hinitial) of liquid that is identical in all the exchange enclosures.

[0010] The invention also relates to the use of the aforementioned installation to produce in parallel several gas streams which have been treated by passing through a volume of liquid contained in each exchange chamber. Brief description of the figures

[0011] The features and advantages of the invention will become clearer upon reading the following detailed description of several particular embodiments of the invention, which particular embodiments are described by way of non-limiting and non-exhaustive examples of the invention, and with reference to the accompanying drawings in which: there figure 1 is an isometric view of an installation according to the invention; The figure 2 is an isometric view of a processing device in the plant of the figure 1 , There figure 3 is a cross-sectional view of the installation of the figure 1 in the vertical cutting plane AA of the figure 1 When the installation's fan is not working, the figure 4 is a cross-sectional view of the installation of the figure 1 in the vertical cutting plane AA of the figure 1 , when the system's fan is running. The figure 5 schematically represents a second embodiment of an installation of the invention. figure 6 schematically represents a third embodiment of an installation of the invention. figure 7 is a schematic cross-sectional view of a treatment device of a fourth embodiment of an installation of the invention, when the installation's air handling system is shut down. figure 8 is a schematic cross-sectional view of a treatment device of said fourth embodiment of an installation of the invention, when the air handling means of the installation are in operation. figure 9 is a schematic cross-sectional view showing the three processing devices of said fourth embodiment of an installation of the invention. Figure 10is a schematic cross-sectional view of a treatment device of a fifth embodiment of an installation of the invention, when the installation's air handling system is shut down. figure 11 is a schematic cross-sectional view of a treatment device of said fifth embodiment of an installation of the invention, when the air handling means of the installation are in operation. figure 12 is a schematic cross-sectional view showing the three processing devices of said fifth variant of an embodiment of an installation of the invention. Detailed description

[0012] With reference to the particular variant of the implementation of the figure 1, the installation 1A for the production and processing of a gaseous stream includes a liquid reserve consisting of a tank 3 open at the top and intended to contain a liquid bath L, and for example water, and three processing devices 2, each comprising an exchange chamber 20.

[0013] For supplying tank 3 with liquid, and in particular water, installation 1A also includes liquid supply means (not shown in the figure 1 ) comprising a liquid supply conduit which opens into tank 3, above the liquid bath, and which is equipped with a supply valve allowing control of the liquid supply to tank 3.

[0014] Installation 1A also includes means of evacuation (not shown on the figure 1) comprising a drain pipe which communicates at the bottom with the interior of tank 3, below the surface of the liquid bath contained in tank 3, and which is equipped with a drain valve allowing control of the evacuation of the liquid outside of tank 3.

[0015] With reference to the figure 2 Each heat exchange enclosure 20 comprises four side walls 20a, which are assembled with a top wall 20b to define an internal chamber 20c, which in this particular example has a horizontal quadrangular cross-section. The geometry of this horizontal cross-section is irrelevant to the invention. In another embodiment, this horizontal cross-section can be arbitrary and, for example, circular or polygonal.

[0016] The lower face of the lower part 20d of each exchange chamber 20 is open and thus forms a liquid inlet opening 20e. This lower part 20d of each exchange chamber 20 is positioned in the tank 3, for example by being placed on the bottom wall of the tank 3, such that by filling the tank 3 with a sufficient level of liquid, the lower part 20d of each exchange chamber 20 is immersed in the liquid bath contained in the tank 3, and the immersed part of each exchange chamber 20 contains a liquid bath having an initial volume V initial.

[0017] In the specific example illustrated in the figures, to reduce space requirements, the heat exchange enclosures 20 are placed side by side. In another variant, they could be spaced apart.

[0018] Preferably, as illustrated in the attached figures, the heat exchange enclosures 20 are all identical. In another variant, they could be different.

[0019] With reference to the figure 2 Each heat exchange chamber 20 has in its upper wall 20b at least one gas flow discharge opening 20f. Each device 2 has at least one vertical injection duct 21 inside the heat exchange chamber 20. This injection duct 21 has, at its upper part, a gas flow inlet opening 21a and at its lower part, a gas flow discharge opening 21b.

[0020] With reference to the figure 1 The installation 1A further includes air handling means 4 comprising a fan 40. The air intake 40a of this fan 40 is connected, by means of a duct 41 and a hood 42, to all the exhaust openings 20f of all the exchange enclosures 20. The air exhaust 40b of this fan 40 opens into the open air.

[0021] In another variant, the air outlet 40b of the fan 40 can be connected to a duct to be sent to another device in another installation.

[0022] In the embodiment shown on the figure 1 The fan 40 is a centrifugal fan. Within the scope of the invention, the aerodynamic means 4 may comprise any known type of gas compressor; the fan 40 may also be an axial fan, a pump, etc.

[0023] Furthermore, in the illustrated variant, a single fan 40 common to all devices 2 is implemented. In another variant, several fans 40 could be implemented in parallel and, for example, one fan 40 for each processing device 2.

[0024] When the aerodynamic means 4 are stopped, the tank 3 contains an initial volume of liquid L corresponding to an initial liquid level ( figure 3 / initial liquid height H) in the tank 3 outside the exchange chambers 20 of the treatment devices 2. The exchange chambers 20 being in hydraulic communication with each other via their liquid inlet opening 20e and via the tank 3, the lower submerged part of each exchange chamber 20 contains an initial volume V of liquid, which is such that the initial height H of liquid in each exchange chamber 20 is identical in all the exchange chambers 20 and is sufficient at least so that the discharge opening 21b of the injection conduit 21 is positioned below the surface S of liquid in the exchange chamber 20.

[0025] Preferably, these initial volumes of liquid V are also identical in all exchange chambers 20.

[0026] Preferably, as illustrated on the figure 3, the evacuation openings 21b of the injection ducts 21 are all positioned at the same depth relative to the surface S of the initial volume V of liquid contained in each exchange chamber 20 when the aerodynamic means 4 are at a standstill.

[0027] When the fan 40 is operated, the interior of each heat exchanger 20 is simultaneously depressurized. When the fan 40 is operating, the pressure Pin at the inlet of each injection duct 21 is greater than the pressure Pout above the volume of liquid in the heat exchanger 20. This pressure difference ΔP (ΔP = Pin - Pout) results in each heat exchanger 20 ( figure 4 ) by a rise in the level ( Figure 4 / height h) of the liquid in each exchange chamber 20 and a drop in the liquid level ( Figure 4 / height H) in tray 3 outside the exchange enclosures 20.

[0028] The volume of liquid V and the level h of liquid in each exchange chamber 20 depend on this pressure difference ΔP. On the figure 4 It was assumed that the pressure differences ΔP in each heat exchange chamber 20 were identical, resulting in identical liquid levels h. Within the scope of the invention, the pressure differences ΔP may be different, resulting in different liquid levels h in the heat exchange chambers 20.

[0029] When the fan 40 is operating, it simultaneously and parallel-drawn a gaseous incoming flow F into each exchange chamber 20 ( figure 1), from outside the exchange enclosures 20, each incoming gas flow F entering the injection duct 21 of the corresponding exchange enclosure 20 through the inlet opening 21a of this duct 21. In this particular application, the inlet openings 21a open to the free air, each gas flow F is an air flow from the air in the external environment of the exchange enclosures 20.

[0030] For each heat exchange chamber 20, this incoming gas flow F (untreated) is introduced into the non-immersed portion of the injection duct 21, passes through the discharge opening 21b of the lower submerged portion of the injection duct 21, and is introduced into the volume of liquid V contained in the lower submerged portion of the chamber, below the surface S of said liquid volume. An outgoing gas flow F', treated by direct contact with said liquid volume contained in the heat exchange chamber 20, rises inside the heat exchange chamber 20, outside the injection duct 21, and is discharged from said heat exchange chamber by passing through the discharge opening 20f of the chamber.

[0031] These outgoing gas flows F' are drawn in by the fan 40 and evacuated in the form of a gas flow F" ( Figure 1 ).

[0032] When the temperature of the volume of liquid V in the enclosure 20 is different from the temperature of the gaseous flow F before its introduction into the volume V of liquid, heat exchanges occur between the gas and the liquid by sensible heat and latent heat.

[0033] When the temperature TLiquid of the liquid volume is lower than the initial temperature TInitial of the gas flow F before its introduction into the liquid volume, the gas flow F' is cooled. More specifically, the temperature of the outgoing gas flow F' has been reduced and can, for example, be substantially equal to the temperature TLiquid of the liquid volume. As a result, the gas airflow F' exiting the device 1 has been dehumidified relative to the incoming gas flows F, the absolute humidity (weight of water per volume of air) in the outgoing gas flow F' being lower than the absolute humidity of the incoming gas flow F.

[0034] Conversely, when the temperature of the liquid volume (TLiquid) is higher than the initial temperature (TInitial), the outgoing gas flow (F') is heated and may, for example, be at a temperature approximately equal to the liquid temperature (TLiquid) of the liquid volume. Consequently, the gas flow (F') exiting device 1 is humidified relative to the incoming gas flow (F), with the absolute humidity (weight of water per volume of air) in the outgoing gas flow (F') being greater than the absolute humidity of the incoming gas flow (F).

[0035] In certain applications, the treatment devices 2 can be used to filter or purify the incoming gas stream F by passing it through a volume of liquid V. The treatment devices 2 can also be used to condense or evaporate one or more constituents carried by the incoming gas stream F, by passing them through a volume of liquid V. Depending on the application, the temperature of the liquid volume may be higher or lower than the temperature of the incoming gas stream F, or substantially equal to the temperature of the incoming gas stream F. When the temperature of the liquid volume is substantially equal to the temperature of the incoming gas stream F, an outgoing gas stream F' is produced at the outlet of the device 1, which has not been heated or cooled, but is substantially at the same temperature as the incoming gas stream F.

[0036] The invention advantageously allows operation with a high flow rate at the outlet of the fan 40, for example, exceeding 10,000 m³ / h, and even more specifically in certain applications exceeding 100,000 m³ / h, without compromising the quality of the treated gas streams F'. The flow rates of treated gas streams can also be easily increased by increasing the number of treatment devices 2 without compromising the quality of the treated gas streams F'.

[0037] It is important to note that in many applications, the Pin pressure or the Pout pressure may differ from one treatment device 2 to another and / or may vary differently over time from one treatment device 2 to another. The same applies to the flow rates of the gas streams F and F'.

[0038] In the invention, when the aerodynamic means 4 are stopped, the initial liquid level H in the exchange chambers 20 is always identical for all the treatment devices 2, which advantageously allows the exiting gaseous flows F' from the exchange chambers 20 to have substantially the same characteristics, particularly with regard to their temperature and humidity level.Comparatively, if the liquid reserve L was not common to all the treatment devices, but each device 2 had its own independent tank 3 not communicating hydraulically with the other tanks 3, in this case it would be necessary to implement an extremely complicated and unreliable regulation to try to automatically maintain the same initial liquid level H in all the enclosures 20, in case of a pressure difference Pin or a pressure difference Pout in at least one of the treatment devices 2 compared to the other treatment devices.

[0039] The invention is not limited to the use of water as the liquid L, but extends to any other type of liquid. By way of non-limiting and non-exhaustive examples, it may be advantageous in certain applications to use a liquid L whose freezing point at atmospheric pressure is below 0°C, such as water containing additives like salts, carbohydrates, glycol, or alcohol. It may also be advantageous to use oil as the liquid L.

[0040] In the variant described, the fan 40 creates the gas flows F and F' by suction. In another variant, the fan 40 could be connected to the inlet openings 21a of the injection ducts 21, so as to create these gas flows F and F' by blowing rather than by suction.

[0041] In a variant of the figure 1The upper part of the tank 3 is open, with the liquid volume outside the exchange chambers 20 at atmospheric pressure. In another variant, the tank 3 could be sealed airtight.

[0042] We have schematically represented on the figure 5 , another configuration of a 1B installation in which the exchange enclosures 20 share the same tray 3, as in the variant of the figure 1 , but they are not joined together.

[0043] We have schematically represented on the figure 6, another configuration of an installation 1C in which the tank 3 is in two parts of tank 3a and 3b, which communicate hydraulically with each other by means of pipes 3c, so that, when the aerodynamic means are stopped the two parts 3a and 3b of tank 3 contain the same level of liquid corresponding to an initial height H of liquid in each exchange chamber 20 which is identical in all the exchange chambers 20.

[0044] We have represented on the figures 7 to 9 , another embodiment of a 1D installation according to the invention, which comprises three processing devices 2, but which, unlike the variants of figures 1 to 6, is devoid of tray 3. In these figures, the aerodynamic means have not been represented, and similarly to what has been previously described, these aerodynamic means include a fan or compressor whose air intake is connected in parallel to all the exhaust openings 20f of all the exchange enclosures 20.

[0045] With reference to the figure 7 In this variant, each treatment device 2 includes an injection conduit 21, which is external to the exchange chamber 20. This injection conduit 21 has an inlet opening for a gas flow 21a communicating with the outside of the exchange chambers 20 of the installation 1D and an outlet opening for a gas flow 21b communicating with the inside of the exchange chamber 20 of the treatment device 2.

[0046] With reference to the figure 9In this variant, the exchange chambers 20 are in hydraulic communication with each other by means of openings 20g provided in the walls 20a separating the exchange chambers 20.

[0047] For supplying the heat exchange chambers 20 with liquid, and in particular water, the installation 1D further includes liquid supply means 11 comprising a supply conduit 11a, which opens into one of the chambers 20, and which is equipped with a supply valve 11b for controlling the liquid supply to the heat exchange chambers 20. The installation 1D further includes drainage means 12 comprising a drainage conduit 12a, which communicates at its lower end with the interior of one of the heat exchange chambers 20, below the surface of the liquid bath contained in the chambers, and which is equipped with a drainage valve 12b for controlling the drainage of the liquid from the heat exchange chambers 20.

[0048] With reference to the figure 7 , when the aerodynamic means are stopped, the exchange chambers 20 being in hydraulic communication with each other via the openings 20g, the lower part of each exchange chamber 20 contains an initial volume V of liquid, which is such that the initial height H of liquid in each exchange chamber 20 is identical in all the exchange chambers 20 and is sufficient at least so that the evacuation opening 21b of the injection duct 21 is positioned below the surface S of liquid in the exchange chamber 20.

[0049] When the air handling units are operated, the interior of each exchange chamber 20 is simultaneously depressurized. The pressure Pin at the inlet of each injection duct 21 is greater than the pressure Pout above the volume of liquid in the exchange chamber 20. This pressure difference ΔP (ΔP = Pin - Pout) translates in each exchange chamber 20 ( figure 8 ) by a rise in the level ( Figure 8 / height h) of the liquid in each exchange chamber 20 and a drop in the liquid level ( Figure 8 / height H) in each injection duct 21 outside the exchange chambers 20.

[0050] During operation, when the pressure differences ΔP in each heat exchanger 20 are identical, the liquid levels h in each heat exchanger 20 are identical. Conversely, if the pressure differences ΔP are different during operation, then the liquid levels h in the heat exchangers 20 are different.

[0051] We have represented on the Figures 10 to 12 , another variant of an installation 1E according to the invention, which includes three treatment devices 2. In these figures, the aerodynamic means have not been shown and similarly to what has been previously described include a fan or compressor whose air intake is connected in parallel to all the exhaust openings 20f of all the exchange enclosures 20.

[0052] With reference to the Figure 10, in this variant each treatment device 2 includes an injection duct 21, which is partly internal to the exchange chamber 20 and which includes an air inlet opening 21a communicating with the outside of the exchange chambers 20 of the installation 1E and an air outlet opening 21b communicating with the inside of the exchange chamber 20 of the treatment device 2.

[0053] With reference to the figure 12 In this variant, the exchange chambers 20 are spaced apart and are in hydraulic communication with each other by means of conduits 20h.

[0054] The installation of the invention can be used in all applications where it is useful to treat a gas stream by passing it through a volume of liquid. It thus finds application in various fields such as, for example, and not exhaustively, the recovery of heat from a gas stream, and in particular from a hot air stream or from industrial fumes, the production of a gas stream that is heated or cooled by passing through said volume of liquid, the production of a gas stream whose temperature is controlled and / or whose absolute humidity is controlled, the humidification or dehumidification of a gas stream, the purification or filtration of a gas stream, the heating or air conditioning of a room or industrial, commercial, or domestic buildings, the control of the humidity of a room or industrial, commercial, or domestic buildings.The resulting gas stream can also be used to cool, heat, humidify or dehumidify any type of object or surface.

Claims

1. Facility (1A; 1B; 1C; 1D; 1E) for producing and treating a gas stream, said facility including at least two treatment devices (2) each including an exchange enclosure (20) containing a liquid bath in its bottom, wherein each exchange enclosure includes at least one opening (20f) for discharging a gas stream, wherein each treatment device (2) includes at least one injection conduit (21) having at least one intake opening (21a) and at least one discharge opening (21b), said facility further including aeraulic means (4), which are connected to all the discharge openings (20f) of the exchange enclosures (20) or which are connected to all the intake openings (21a) of the injection conduits (21), and which, during operation, make it possible to create, by suction or blowing, simultaneously and in parallel for each treatment device (2), an incoming gas stream (F) coming from the outside of the exchange enclosures (20), wherein each injection conduit (21) of the corresponding treatment device (2) is designed to introduce each corresponding incoming gas stream (F) and to allow said stream to pass through the discharge opening (21b) of the injection conduit (21), said discharge opening (21b) of the injection conduit (21) being designed to introduce said stream into the liquid bath contained in the bottom of the exchange enclosure (20), below the surface (S) of said liquid bath, and the exchange enclosure is designed to allow an outgoing gas stream (F'), treated by direct contact with said liquid bath, to rise up inside the exchange enclosure, and to discharge said outgoing gas stream out of said exchange enclosure (20) by allowing it to pass through the discharge opening (20f) of the exchange enclosure (20), characterized in that the exchange enclosures (20) communicate hydraulically with one another so that, when the aeraulic means (4) are not operating each exchange enclosure (20) contains, at its bottom, an initial volume (Vinitial) of liquid, with an initial level (Hinitial) of liquid which is identical in all the exchange enclosures (2).

2. Facility according to claim 1, wherein the discharge openings (21b) of the injection conduits (21) are all positioned substantially at the same depth relative to the surface (S) of the initial volume (Vinitial) of liquid contained in each exchange enclosure (20) when the aeraulic means (4) are not operating.

3. Facility according to any one of the preceding claims, wherein the initial volumes (Vinitial) of liquid in all the exchange enclosures (20) are identical.

4. Facility according to any one of the preceding claims, wherein the aeraulic means (4) include a fan or compressor (40) connected to all the discharge openings (20f) of the exchange enclosures (20) or connected to all the intake openings (21a) of the injection conduits (21).

5. Facility (1A) according to any one of the preceding claims, including a supply (3) of liquid (L), and wherein the bottom (20d) of each exchange enclosure (20) includes at least one liquid intake opening (20e) and is submerged in the same liquid bath (L) contained in said supply (3), so that, when the aeraulic means (4) are not operating, the bottom of each exchange enclosure (20) contains an initial volume (Vinitial) of this liquid, with a level (Hinitial) of liquid which is identical in all the exchange enclosures (20).

6. Use of the facility according to any one of the preceding claims for producing multiple gas streams (F') in parallel which have been treated by being passed through a volume of liquid contained in each exchange enclosure (20).