Air dehumidification system within a closed culture structure and closed culture structure equipped with such a dehumidification system.

Abstract

The invention relates to an air dehumidification system (200) within a closed culture structure comprising a thermodynamic circuit, said thermodynamic circuit comprising: an evaporator (102), for cooling and dehumidifying the air (114) in said culture structure by heat exchange with a heat transfer fluid of the thermodynamic circuit, a first condenser (104) for heating the air (114) at the outlet of the evaporator (102) by heat exchange with said heat transfer fluid, an expansion valve (106), between said first condenser and said evaporator for lowering the pressure of the heat transfer fluid from said first condenser (104) and supplying it to said evaporator (102), and a compressor (108), between said evaporator (102) and said first condenser (104) for increasing the pressure of the heat transfer fluid from said evaporator;in which the thermodynamic system circuit further comprises a second condenser (110), supplying said first condenser (104) with heat transfer fluid, to condense said heat transfer fluid at least partially by heat exchange with a first flow. It also relates to a closed culture structure comprising an air dehumidification system. Figure: Fig. 2;

Description

Title of the invention: Air dehumidification system within a closed cultivation structure and closed cultivation structure equipped with such a dehumidification system.

[0001] The present invention relates to a system for dehumidifying air within a closed cultivation structure. It also relates to a closed cultivation structure equipped with a dehumidification system.

[0002] The field of the invention is the field of dehumidification of air in closed growing structures. State of the art

[0003] Humidity is a common problem for crops grown in enclosed structures. Excess moisture condenses on the crop and degrades its quality. In addition, humid areas promote the growth of diseases, fungi, pests, and mold.

[0004] In order to evacuate humidity in growing structures, it is known to heat the air contained in these structures then to evacuate the hot and humid air through openings provided in the upper part of said structure and to bring in cold air coming from outside said structure.

[0005] There are also thermodynamic dehumidification systems or hygroscopic dehumidification systems.

[0006] However, these dehumidification systems are excess heat and therefore increase the air temperature when placed in an enclosed growing structure.

[0007] Furthermore, the temperature of the air leaving current dehumidification systems is higher than the desired temperature for the crops, which generates hot zones within the crop structures that they dehumidify, which is detrimental to the cultivation of the plants present in said hot zones.

[0008] An aim of the present invention is to remedy at least one of the aforementioned drawbacks.

[0009] Another aim of the present invention is to propose a solution for dehumidifying the air within a closed culture structure allowing better control of the temperature within said structure and thus making it possible to obtain better culture conditions.

[0010] Another object of the present invention is to provide a dehumidification solution capable of dehumidifying without increasing the temperature of the air in the structure. Statement of the invention

[0011] The invention makes it possible to achieve at least one of these aims by means of a system for dehumidifying the air within a closed cultivation structure comprising a thermodynamic circuit, said thermodynamic circuit comprising: • an evaporator, for cooling and dehumidifying the air in said growing structure by heat exchange with a heat transfer fluid from the thermodynamic circuit, • a first condenser to heat the air leaving the evaporator by heat exchange with said heat transfer fluid, • an expansion valve, between said first condenser and said evaporator to lower the pressure of the heat transfer fluid coming from said first condenser and supply it to said evaporator, and • a compressor, between said evaporator and said first condenser to increase the pressure of the heat transfer fluid coming from said evaporator; in which the system thermodynamic circuit further comprises a second condenser, supplying said first condenser with heat transfer fluid, to at least partially condense said heat transfer fluid by heat exchange with a first flow, said first flow being: • an airflow coming from outside the enclosed growing structure and discharged outside; or • a flow of heat transfer fluid discharged into a tank.

[0012] The invention proposes an air dehumidification system for removing part of the heat in the thermodynamic circuit, either outside the closed growing structure by exchange with a first air flow coming from outside the growing structure, or in a tank provided for this purpose. Thus, it is possible to dehumidify the air in a closed growing structure without increasing the air temperature inside the structure, by removing, at least in part, the excess heat from the dehumidification system outside the closed growing structure, or in a tank provided for this purpose, by the first flow.

[0013] The solution according to the invention therefore allows better control of the temperature of the air in the closed culture structure during dehumidification thereof. Indeed, it is possible to control the temperature of the air leaving the first condenser. The system according to the invention therefore makes it possible to reduce the temperature difference between the air leaving the first condenser and the rest of the air contained in the closed culture structure. Consequently, it is possible to avoid the presence of hot zones in said culture structure, in particular at the outlet of the first condenser.

[0014] Furthermore, since the system of the invention is capable of dehumidifying the air in an enclosed growing structure without heating it, an enclosed growing structure equipped with such a system does not need to be opened to replace hot air with cold air from outside. Thus, an enclosed growing structure equipped with a system of the invention can remain closed during cultivation, which reduces the risk of allowing insects and other pests that could harm crops to enter the structure.

[0015] Therefore, for at least one of the aforementioned reasons, the system according to the invention allows better control of the culture environment within a closed culture structure.

[0016] As indicated above, according to embodiments, the first flow may be a flow of air coming from outside the enclosed growing structure and discharged to the outside. Thus, the dehumidification of the air in the enclosed structure is carried out with the outside air and discharged to the outside after dehumidification.

[0017] According to embodiments, the first flow may be a flow of heat transfer liquid, such as for example water, discharged into a reservoir. The latter may be located outside said closed culture structure, or inside the closed culture structure. In these embodiments, the heat transfer liquid is charged with calories, coming from the closed culture structure, and which are transferred to it within the second condenser. This first flow of heat transfer liquid is stored, in a reservoir or in a tank. These calories can then be used, immediately or later, directly or indirectly, to heat the air inside the closed structure, if necessary, such as for example in the mid-season.

[0018] According to embodiments, the system according to the invention may comprise a combination of what has just been described, namely: • a second condenser crossed by a first flow of air coming from outside the closed culture structure and discharged outside, and • a second condenser crossed by a first flow of heat transfer liquid, such as water, discharged into a tank.

[0019] Advantageously, the second condenser can be equipped with at least one fan, and more generally a drive means, to generate and control the first flow.

[0020] Thus, the system is capable of regulating the heat exchange in the second condenser, and therefore of regulating the proportion of the heat transfer fluid passing through the second condenser which is condensed by said second condenser. Consequently, it is possible to regulate the proportion of the heat transfer fluid remaining to be condensed by the first condenser.

[0021] In other words, it is possible to control the proportion of the heat transfer fluid in the gaseous state and in the liquid state at the outlet of the second condenser supplying the first condenser.

[0022] Thus, when the air in the closed growing structure needs to be cooled, for example in summer and / or during the day or when growing lamps are on, it is possible to increase the speed of said at least one drive means, and in particular of the fan, equipping the second condenser so as to increase the heat exchanges within said second condenser. In this case, the heat transfer fluid at the outlet of the second condenser is further condensed and the proportion of the fluid in the gaseous state is reduced. Consequently, the heat exchanges in the first condenser, between the heat transfer fluid and air at the outlet of the evaporator, are reduced. Thus, the cold air at the outlet of the evaporator is less heated and the temperature of the air included in the closed growing structure can be reduced.

[0023] Furthermore, it is possible to completely condense the heat transfer fluid passing through the second condenser. In this case, the second condenser supplies the first condenser with a heat transfer fluid only in the liquid state. Thus, the heat exchanges in the first condenser, between the heat transfer fluid and air leaving the evaporator, are negligible, or even non-existent. Consequently, it is possible not to heat the air flow leaving the evaporator and therefore to maximize the cooling of the air included in the closed culture structure.

[0024] Furthermore, when the air in the closed growing structure needs to be heated, for example in winter and / or during the night or when growing lamps are off, it is possible to reduce the speed of the drive means, and in particular of a fan, equipping the second condenser so as to reduce the heat exchanges within said second condenser. In this case, the heat transfer fluid at the outlet of the second condenser is less condensed and the proportion of the heat transfer fluid in the gaseous state is increased. Consequently, the heat exchanges in the first condenser, between the heat transfer fluid and air at the outlet of the evaporator, are increased. Thus, the cold air at the outlet of the evaporator is heated more and the temperature of the air included in the closed growing structure can be increased.

[0025] In addition, it is possible to stop said at least one drive means, and in particular the fan, equipping the second condenser so as to reduce as much as possible the heat exchanges in the second condenser. This makes it possible to maximize the heat exchanges in the first condenser and therefore to maximize the heating of the air included in the closed culture structure.

[0026] Advantageously, the system may comprise at least one fan for generating and controlling the air flow, passing through the first condenser and the evaporator.

[0027] Thus, it is possible to adapt the flow speed and therefore to regulate the heat exchanges in the first condenser and in the evaporator.

[0028] By way of non-limiting example, at least one fan can be positioned: • upstream of the evaporator so as to push air into the evaporator then into the first condenser, • between the first condenser and the evaporator so as to draw air through the first condenser and push air through the evaporator, and / or • downstream of the first condenser so as to draw air into the evaporator and into the first condenser.

[0029] Alternatively, when the second condenser is equipped with at least one drive means, and in particular a fan, for generating and controlling the first flow, the system according to the invention may comprise at least one constant-speed fan for generating an air flow, passing through the first condenser and the evaporator. Thus, the speed of this air flow is constant. Consequently, the heat exchanges of the heat transfer fluid in the first condenser are not regulated by this flow. Indeed, in this embodiment the heat exchanges in the first condenser are dependent on the proportion of the heat transfer fluid remaining to be condensed at the outlet of the second condenser.

[0030] Thus, in this embodiment, the constant speed fan can be sized to generate an air flow allowing the first condenser to condense the proportion of the heat transfer fluid remaining to be condensed at the outlet of the second condenser even when the fan equipping the second condenser is stopped.

[0031] According to one embodiment, at least one fan of said system may be provided to be activated and / or controlled manually.

[0032] Advantageously, the system may further comprise: • at least one probe for measuring temperature and / or humidity level in the closed growing structure, and • a control unit to adjust the speed of: • the drive means, and in particular the fan, equipping the second condenser, and / or • the fan equipping the first condenser; depending on at least one temperature and / or a measured humidity level.

[0033] Thus, it is possible to regulate the heat exchanges in the evaporator, the first condenser and / or in the second condenser as a function of data from temperature and / or humidity measured in said structure. Therefore, it is possible to adapt the behavior of the system in real time based on temperature and / or humidity data. Thus, it is possible to better control the climate inside a closed growing structure and therefore obtain better quality crops.

[0034] By way of non-limiting examples, at least one probe for measuring a temperature and / or a humidity level can be provided to be positioned: • in an upper part of a cultivation structure, • in a lower part of a growing structure, or • at the outlet of the first condenser, • etc.

[0035] According to one embodiment, the evaporator may be provided to be arranged outside the closed culture structure and the first condenser may be provided to be arranged inside the closed culture structure. In this embodiment, the evaporator must be arranged so as to allow the air in the structure to pass through the evaporator and then the first condenser without this air, coming from inside the structure, being mixed with the air outside the structure. By way of non-limiting example, dedicated conduits may be used.

[0036] Alternatively, the evaporator and the first condenser may be provided to be arranged outside the closed culture structure. In this embodiment, the evaporator and the first condenser must be arranged so as to allow the air in the structure to pass through the evaporator and then the first condenser without this air, coming from inside the structure, being mixed with the air outside the structure. By way of non-limiting example, dedicated conduits may be used.

[0037] Advantageously, the first condenser and the evaporator may be provided to be arranged inside the closed culture structure.

[0038] According to one embodiment, the second condenser may be provided to be arranged inside the structure. In this case, the second condenser must be arranged so as to allow said first flow to pass through said second condenser without this first flow being mixed with the air within the structure. By way of non-limiting example, conduits dedicated to the first flow may be used.

[0039] Advantageously, the second condenser can be provided to be arranged outside the closed culture structure.

[0040] Thus, the exchanges between the heat transfer fluid and the first flow are facilitated, in particular when the first is an air flow outside the closed culture structure. Indeed, it is simpler to supply outside air to the second condenser and then discharge this air outside the closed growing structure when said second condenser is outside said structure.

[0041] In addition, having a condenser designed to be placed outside allows a greater part of the interior volume of the structure to be dedicated to crops and therefore allows greater production.

[0042] Advantageously, the thermodynamic circuit may further comprise a heat transfer fluid reservoir, arranged between the first condenser and the expansion valve.

[0043] Thus, it is possible to guarantee proper operation of the expansion valve and therefore of the evaporator. Indeed, the use of a reservoir upstream of the expansion valve makes it possible to guarantee that heat transfer fluid is always available for the expansion valve.

[0044] Advantageously, the thermodynamic circuit may comprise at least one constant pressure valve arranged downstream of the first condenser.

[0045] Thus, it is possible to control the condensation pressure of the heat transfer fluid and therefore the condensation temperature of the heat transfer fluid. This is particularly advantageous when the air temperature outside the enclosed growing structure is colder than the air temperature inside the growing structure, for example in winter.

[0046] Indeed, under these conditions and without a constant pressure valve, the first condenser can be supplied with a heat transfer fluid at a temperature too low to be condensed by heat exchange with the air included in the closed culture structure.

[0047] As a non-limiting example, without a constant pressure valve, when the temperature inside the structure is 20°C and the temperature outside the structure is 0°C, the heat transfer fluid may have a condensation temperature of approximately 10°C. In addition, under these conditions, the heat transfer fluid leaving the second condenser and supplying the first condenser may be at a temperature of approximately 10°C. Consequently, the heat transfer fluid cannot be condensed by heat exchange with the air included in the structure, at a temperature of 20°C.

[0048] Thus, the use of a constant pressure valve downstream of the first condenser makes it possible to increase the condensation temperature of said heat transfer fluid and therefore makes it possible to condense it in the first condenser even when the temperature outside the structure is lower than that inside the structure.

[0049] According to an advantageous embodiment, the constant pressure valve can be provided to close when the compressor is stopped. Thus, the constant pressure valve can act as a non-return valve. This is particularly advantageous for embodiments comprising a liquid reservoir heat transfer fluid, arranged between the first condenser and the expansion valve. Indeed, in such an embodiment, the constant pressure valve prevents the migration of the heat transfer fluid from the tank to the first condenser when the system is stopped.

[0050] Alternatively, or in addition, the thermodynamic circuit may comprise a non-return valve disposed between the first condenser and the second condenser.

[0051] Thus, it is possible to prevent the heat transfer fluid from migrating from the first condenser to the second condenser. This is particularly advantageous for embodiments of the system where the second condenser is intended to be arranged outside said culture structure. Indeed, in such an embodiment, when the system is stopped and the temperature outside the enclosed culture structure is lower than the temperature inside the enclosed structure, the heat transfer fluid has a higher temperature and pressure in the first condenser than in the second, which can cause migration of the fluid from the first condenser to the second condenser. Consequently, upon restart, the expansion valve may not be sufficiently supplied with heat transfer fluid, the evaporation pressure may be lowered and cause the compressor to shut down for safety reasons.Additionally, fluid buildup in the second condenser may cause a blockage and increase the pressure at the compressor outlet, which may also cause the compressor to shut down for safety reasons.

[0052] According to one embodiment, the compressor may be a fixed speed compressor.

[0053] Advantageously, the compressor may be a variable speed compressor.

[0054] Thus, it is possible to regulate the quantity of heat transfer fluid drawn into the expansion valve and the evaporator. Regulating the quantity of fluid passing through the evaporator in this way makes it possible to regulate the possible heat exchanges in the evaporator and therefore to regulate the dehumidification. Thus, it is possible to limit the quantity of dehumidification. In addition, it is possible to cool the air passing through the evaporator without dehumidifying it.

[0055] Preferably, when the system comprises a control unit, the variable speed compressor can be controlled by said control unit.

[0056] According to another aspect of the invention, there is provided a closed culture structure equipped with a system according to the invention.

[0057] Advantageously, the closed culture structure can be: • a greenhouse, • a growing room, • a grow tent, or • a growing cupboard, • etc.

[0058] The enclosed growing structure may, for example, be a structure intended to be placed outdoors or a structure intended to be placed inside a building. The enclosed growing structure may be a fixed, non-movable structure, or a movable or even mobile structure.

[0059] In addition, the enclosed growing structure can be equipped with growing lamps.

[0060] Furthermore, the enclosed growing structure may be a so-called opaque structure, each of whose walls is opaque to light, so that light coming from outside the enclosed growing structure cannot penetrate the interior of said enclosed growing structure. In addition, when such an opaque structure is equipped with growing lamps, the light generated inside the opaque structure is contained inside it. This is particularly advantageous for structures arranged inside buildings or dwellings.

[0061] Alternatively, the structure may comprise at least one transparent or translucent wall, so as to allow light coming from outside the closed culture structure to penetrate inside said structure. Description of figures and embodiments

[0062] Other advantages and characteristics will appear on examining the detailed description of a non-limiting embodiment, and the appended drawings in which: • [Fig.l] is a schematic representation of a non-limiting example of an air dehumidification system within a closed cultivation structure; • [Fig.2] is a schematic representation of another non-limiting example of an air dehumidification system within a closed cultivation structure; • [Fig.3a] and 3b are schematic and partial representations of a non-limiting example of a closed culture structure equipped with a dehumidification system; and • [Fig.4a] and 4b are schematic and partial representations of a building comprising another non-limiting example of an enclosed cultivation structure equipped with a dehumidification system.

[0063] It is understood that the embodiments which will be described below are in no way limiting. In particular, it will be possible to imagine variants of the invention comprising only a selection of characteristics described below isolated from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention compared to the prior art. This selection includes at least one preferably functional characteristic without structural details, or with only a part structural details if this part is only sufficient to confer a technical advantage or to differentiate the invention from the prior art.

[0064] In the figures, the elements common to several figures retain the same reference.

[0065] [Fig.l] is a schematic representation of a non-limiting exemplary embodiment of an air dehumidification system within a closed growing structure.

[0066] The system 100 for dehumidification of the air of a closed culture structure comprises a thermodynamic circuit comprising a heat transfer fluid.

[0067] The thermodynamic circuit comprises an evaporator 102, for cooling and dehumidifying the air within said culture structure by heat exchange with the heat transfer fluid of the thermodynamic circuit.

[0068] The thermodynamic circuit further comprises a first condenser 104 for heating the air leaving the evaporator 102 by heat exchange with said heat transfer fluid.

[0069] In addition, the thermodynamic circuit comprises an expansion valve 106, downstream of said first condenser 104 and upstream of said evaporator 102 as well as a compressor 108, downstream of said evaporator 102 and upstream of said first condenser 104.

[0070] Furthermore, the thermodynamic circuit further comprises a second condenser 110, supplying said first condenser 104 with heat transfer fluid. This second condenser 110 of the system 100 is provided to at least partially condense said heat transfer fluid, coming from the compressor 108, by heat exchange with a first air flow 112, coming from outside said closed culture structure and discharged outside said closed culture structure.

[0071] Thus, the air dehumidification system 100 is capable of removing a portion of the heat located in the thermodynamic circuit to the exterior of the enclosed growing structure. Thus, it is possible to dehumidify the air in a enclosed growing structure without increasing the air temperature inside the structure, by removing excess heat from the dehumidification system 100 to the exterior of the enclosed growing structure.

[0072] Thus, during dehumidification of the air in the closed culture structure, illustrated by the air flow 114 passing through the evaporator 102 then the first condenser 104, the system 100 is capable of not increasing the temperature of the air within the closed culture structure.

[0073] When the dehumidification system 100 is in operation, the first condenser 104 supplies the expansion valve 106 with heat transfer fluid in the liquid state. The expansion valve 106 lowers the pressure of the heat transfer fluid and modulates the flow rate of heat transfer fluid in inlet of the evaporator 102. The heat transfer fluid is thus converted to the gaseous state in the evaporator 102 by heat exchange with the air 114 inside the structure. Then, the compressor 108 increases the pressure of the heat transfer fluid coming from the evaporator 102. The excess heat from the system 100 can then be evacuated from the closed culture structure by the second condenser 110 by condensing a portion of the heat transfer fluid by heat exchange with the first air flow 112. The second condenser 110 then supplies the first condenser 104 with heat transfer fluid which condenses the portion of the heat transfer fluid still in the gaseous state, by heat exchange with the flow 114.

[0074] [Fig.2] is a schematic representation of another non-limiting example embodiment of an air dehumidification system within a closed growing structure.

[0075] The system 200 of [Fig.2] comprises all the elements of the device 100 of [Fig.l].

[0076] The system 200 further comprises a first fan 202 equipping the second condenser 110 to generate and control said first air flow 112 passing through the second condenser 110.

[0077] In [Fig.2], the first fan 202 is positioned to push air through the second condenser 110.

[0078] Alternatively or additionally, according to other embodiments (not shown), the system 200 may include a fan positioned to draw air through the second condenser 110.

[0079] The system 200 further comprises a second fan 204 for generating and controlling the second airflow 114 passing through the first condenser 104 and the evaporator 102.

[0080] In [Fig.2], the second fan 204 is positioned between the evaporator 102 and the first condenser 104, so as to draw air through the evaporator 102 and push air through the first condenser 104.

[0081] Alternatively or additionally, according to other embodiments (not shown), the system 200 may comprise a fan positioned upstream of the evaporator 102 so as to push air into the evaporator 102 and then into the first condenser 104 and / or downstream of the first condenser 104 so as to draw air into the evaporator 102 and into the first condenser 104.

[0082] Additionally, the system 200 includes a probe 206 for measuring a temperature in the enclosed growing structure as well as a probe 208 for measuring a humidity level in the enclosed growing structure.

[0083] Furthermore, the system 200 comprises a control unit 210 for adjusting the speed of the first fan 202 and the second fan 204 according to at least minus a temperature and / or a humidity level measured by the probe 206 and / or the probe 208 respectively.

[0084] Thus, by regulating the speed of the first fan 202 and therefore by regulating the air flow 112, the control unit 210 of the system 200 is capable of regulating the heat exchange in the second condenser 110, and therefore of regulating the proportion of the heat transfer fluid passing through the second condenser 110 which is condensed by said second condenser 110. Consequently, it is possible to regulate the proportion of the heat transfer fluid remaining to be condensed by the first condenser 104. In other words, the system 200 is capable of controlling the proportion of the heat transfer fluid in the gaseous state and in the liquid state at the outlet of the second condenser 110 supplying the first condenser 104.

[0085] In addition, the control unit 210 is capable of adapting the speed of the fan 204 and therefore of regulating the flow 114 so as to allow the first condenser 104 to condense the proportion of the heat transfer fluid in the gaseous state at the outlet of the second condenser 110.

[0086] Thus, when the control unit 210 reduces the rotation speed of the first fan 202 in order to reduce the proportion of the heat transfer fluid condensed by the second condenser 110, the control unit can increase the rotation speed of the second fan 204.

[0087] Conversely, when the control unit 210 increases the rotation speed of the first fan 202 in order to increase the proportion of heat transfer fluid condensed by the second condenser 110, the control unit can reduce the rotation speed of the second fan 204. Preferably, a minimum rotation speed of the second fan 204 can be predefined. This minimum rotation speed makes it possible to guarantee a flow 114 allowing proper operation of the evaporator 102. Thus, when the system 200 is in operation, the control unit 210 cannot reduce the speed of the second fan 204 below this predefined minimum speed. Furthermore, this minimum rotation speed can be a function of a humidity level measured in the closed culture structure. Thus, it is possible for the minimum rotation speed to be adapted to the desired amount of dehumidification.

[0088] In addition, the control unit 210 is capable of adapting the speed of the second fan 204 and therefore of regulating the flow 114 so as to control the thermal exchanges within the evaporator 102. Thus, it is possible to control the quantity of dehumidification provided by the system 200.

[0089] According to an alternative embodiment not illustrated, the second fan 204 may be a constant speed fan, configured to generate an air flow 114 allowing the first condenser 104 to condense the proportion of the heat transfer fluid remaining to be condensed at the outlet of the second condenser 110 even when the first fan 202 equipping the second condenser 110 is stopped.

[0090] Furthermore, in the embodiment illustrated in [Fig.2], the compressor 108 of the system 200 is a variable speed compressor designed to be controlled by the control unit 210. Thus, the system 200 is capable of regulating the dehumidification. Indeed, by controlling the speed of the compressor 108 it is possible to control the quantity of heat transfer fluid drawn into the expansion valve 106 and into the evaporator 102. Thus regulating the quantity of fluid passing through the evaporator 102 makes it possible to regulate the possible heat exchanges in the evaporator 102 and therefore to regulate the dehumidification.

[0091] In addition, the system 200 comprises a constant pressure valve 212 arranged directly downstream of said first condenser 104. Controlling and setting the required pressure at the outlet of the first condenser 104 makes it possible to control the condensation temperature of the heat transfer fluid.

[0092] This is particularly advantageous when the air temperature outside the enclosed growing structure is colder than the air temperature 114 within the growing structure, for example in winter.

[0093] Indeed, without a constant pressure valve 212, the first condenser 104 can be supplied with a heat transfer fluid at a temperature too low to be condensed by heat exchange with the air 114 included in the closed culture structure.

[0094] Thus, the use of a constant pressure valve 212 downstream of the first condenser makes it possible to increase the condensation temperature of said heat transfer fluid and therefore makes it possible to condense it in the first condenser 104 even when the external temperature outside the structure is lower than that inside the structure.

[0095] Furthermore, the system 200 comprises a non-return valve 214 disposed between said first condenser 104 and said second condenser 110. This valve 214 makes it possible to prevent the heat transfer fluid from the first condenser 104 to the second condenser 110. This is particularly advantageous when the second condenser 110 is intended to be disposed outside the culture structure, as described below in relation to [Fig. 3a] and 3b. Indeed, in such an embodiment, when the system is stopped and the temperature outside the closed culture structure is lower than the temperature inside the closed structure, the heat transfer fluid has a higher temperature and pressure in the first condenser than in the second, which can cause migration of the fluid from the first condenser to the second condenser.

[0096] In addition, the system 200 comprises a liquid reservoir 216 for heat transfer liquid, arranged between said first condenser 104 and the expansion valve 106, more precisely between the constant pressure valve 212 and the expansion valve 106.

[0097] The system 200 is thus capable of guaranteeing proper operation of the expansion valve 106 and therefore of the evaporator 102. Indeed, the use of a reservoir 216 upstream of the expansion valve 106 makes it possible to guarantee that heat transfer fluid is always available.

[0098] According to an alternative embodiment not illustrated, the constant pressure valve 212 can be provided to close when the compressor 108 is stopped. Thus, the constant pressure valve 212 can act as a non-return valve. In such an embodiment, the constant pressure valve 212 makes it possible to prevent the migration of the heat transfer fluid from the reservoir 216 to the second condenser 104 when the system is stopped.

[0099] [Fig.3a] and 3b are schematic and partial representations of an example non-limiting embodiment of a closed culture structure equipped with a dehumidification system.

[0100] In particular, [Fig.3a] illustrates an overall view of the closed culture structure 300 equipped with a dehumidification system 302 according to the invention. [Fig.3b] illustrates, by an enlarged view, the elements included in the frame AA of [Fig.3a], such as the dehumidification system 302 of the closed culture structure 300.

[0101] The closed cultivation structure 300 is a stationary structure of the cultivation greenhouse type. This closed cultivation structure 300 comprises an interior volume 304 delimited by walls 306, a ceiling 308 and a floor 310.

[0102] In the example illustrated in [Fig.3a], the enclosed growing structure 300 is equipped with a growing lamp 312 attached to the ceiling 308. In addition, plants 314 are present inside the growing structure 300.

[0103] For the sake of readability, the system 302 for dehumidifying the air of the closed culture structure 300 is partially illustrated in [Fig.3a] and 3b. Indeed, only the evaporator 102, the first condenser 104, the second condenser 110 and the circuit connecting them are illustrated.

[0104] The dehumidification system 302 may be a system 100 or 200 as described above in relation to FIGURES 1 and 2, or more generally, a system according to the invention.

[0105] The evaporator 102 and the first condenser 104 are arranged inside the culture structure 300 while the second condenser 110 is arranged outside thereof.

[0106] Thus, it is simpler to generate: • the first air flow 112 conveying outside air to the second condenser 110 then rejecting this air outside the closed culture structure 300, and • the air flow 114 located in the closed culture structure 300, passing through the evaporator 102 then the first condenser 104.

[0107] In addition, when the closed cultivation structure 300 is a stationary structure of the cultivation greenhouse type and the second condenser 110 is intended to be arranged outside said structure 300, it is possible to at least partially bury heat transfer fluid conduits connecting elements arranged inside the closed cultivation structure to elements arranged outside the closed cultivation structure. In the exemplary embodiment illustrated in [Fig. 3a] and 3b, the conduit connecting the second condenser 110 to the first condenser 104 is partially buried.

[0108] [Fig.4a] and 4b are schematic and partial representations of a building 400 comprising another non-limiting example of an enclosed cultivation structure 401 equipped with a dehumidification system 402.

[0109] In particular, [Fig.4a] illustrates an overall view of the building 400 structure 401 for closed cultivation equipped with a dehumidification system 402 according to the invention. [Fig.4b] illustrates, by an enlarged view, the elements included in the frame BB of [Fig.4a], such as the dehumidification system 402 of the closed cultivation structure 300.

[0110] The enclosed culture structure 401 is a movable structure of the culture chamber or culture tent type. This enclosed culture structure 401 of FIGURES 4a and 4b comprises all the elements of the enclosed culture structure 300 of FIGURES 3a and 3b.

[0111] For the sake of readability, the system 402 for dehumidifying the air of the closed culture structure 401 is partially illustrated in [Fig.4a] and 4b. Indeed, only the evaporator 102, the first condenser 104, the second condenser 110 and the circuit connecting them are illustrated.

[0112] The dehumidification system 402 may be a system 100 or 200 as described above in relation to FIGURES 1 and 2, or more generally, a system according to the invention.

[0113] The evaporator 102, the first condenser 104 and the second condenser 110 of the system 402 are arranged inside the closed culture structure 401.

[0114] Since the evaporator 102 and the first condenser 104 are arranged in the closed culture structure 401, the air flow 114, of an air included in the closed culture structure 300, passing through the evaporator 102 and then the first condenser 104 is easy to generate.

[0115] Furthermore, the second condenser 110 is connected to the outside of the closed culture structure by air ducts 404 and 406. Thus it is possible to generate the first air flow 112 conveying outside air to the second condenser 110 and then discharging it outside the closed culture structure 401 without this outside air being mixed with the air inside the closed culture structure 401. Thus, the outside air can enter the first air duct 404 through a first opening 408 in the wall 306, pass through the second condenser 110 and then be directed by the second duct 406 towards the outside of the structure 401 through a second opening 408.

[0116] In this example of a movable closed growing structure 401, all the elements of the dehumidification system 402 are arranged inside the structure. This has the advantage of facilitating the movement and installation of this growing structure inside a building and in particular inside homes. However, according to other embodiments, certain elements of the dehumidification system, in particular the second condenser 110, may be provided to be arranged outside said structure in order to maximize the growing space available inside said structure.

[0117] In the non-limiting examples which have just been described with reference to the FIGURES, the system according to the invention comprises a second condenser 110 crossed by a first flow which is a flow of air coming from outside the closed culture structure and discharged into the outside atmosphere.

[0118] According to alternative embodiments not shown, the first flow may be a flow of water, or generally a flow of heat transfer liquid, discharged into a tank, arranged outside or inside the closed culture structure. In this case, the heat transfer liquid is charged with calories, coming from the closed culture structure, and which are transferred to it within the second condenser. This first flow of heat transfer liquid charged with calories can then be stored, for example in a tank or in a tank. These calories can then be used, immediately or later, directly or indirectly, to heat the air inside the closed structure, if necessary, such as for example in the mid-season.

[0119] According to still other alternative embodiments not shown, the system according to the invention can comprise a combination of what has just been described, namely: • a second condenser crossed by a first flow of air coming from outside the closed culture structure and discharged outside, as shown in the FIGURES, and • a second condenser crossed by a first flow of heat transfer liquid discharged into a tank, or a tank, to be reused. The two second condensers can be arranged one behind the other in any order, between the compressor 108 and the first condenser 104.

[0120] Of course, the invention is not limited to the examples detailed above.

Claims

1. Claims System (100;200;302;402) for dehumidifying air within a closed cultivation structure comprising a thermodynamic circuit, said thermodynamic circuit comprising: - an evaporator (102), for cooling and dehumidifying the air (114) located in said culture structure by heat exchange with a heat transfer fluid of the thermodynamic circuit, - a first condenser (104) for heating the air (114) leaving the evaporator (102) by heat exchange with said heat transfer fluid, - an expansion valve (106), between said first condenser and said evaporator for lowering the pressure of the heat transfer fluid coming from said first condenser (104) and supplying it to said evaporator (102), and - a compressor (108), between said evaporator (102) and said first condenser (104) to increase the pressure of the heat transfer fluid coming from said evaporator; characterized in that the system further comprises: - a second condenser (110), supplying said first condenser (104) with heat transfer fluid, to at least partially condense said heat transfer fluid by heat exchange with a first flow (112), said first flow (112) being: - an air flow coming from outside the enclosed growing structure and discharged outside; and / or - a flow of heat transfer fluid discharged into a tank, the second condenser (110) being equipped with a fan (202), to generate and control the first air flow (112), - at least one fan (204) for generating and controlling the air flow (114), passing through the first condenser (102) and the evaporator (104), - at least one probe (206,208) for measuring a temperature and / or a humidity level in the closed culture structure, and - a control unit (210) for adjusting the speed: • of the fan (202), equipping the second condenser (110), and / or, • of the fan (204) equipping the first condenser (102); as a function of at least one temperature and / or a measured humidity level.

2. System (302;402) according to the preceding claim, characterized in that the first condenser (104) and the evaporator (102) are intended to be arranged inside the closed culture structure.

3. System (302) according to any one of the preceding claims, characterized in that the second condenser (110) is intended to be arranged outside the closed culture structure.

4. System (200) according to any one of the preceding claims, characterized in that the thermodynamic circuit further comprises a heat transfer fluid reservoir (216), disposed between the first condenser (104) and the expansion valve (102).

5. System (200) according to any one of the preceding claims, characterized in that the thermodynamic circuit comprises at least one constant pressure valve (212) arranged downstream of the first condenser (104).

6. System (200) according to any one of the preceding claims, characterized in that the thermodynamic circuit comprises a non-return valve (214) disposed between the first condenser (104) and the second condenser (110).

7. System (200) according to any one of the preceding claims, characterized in that the compressor (108) is a variable speed compressor.

8. Closed culture structure (300;401) equipped with a system (302;402) according to any one of the preceding claims.

9. Growing structure (300;401) according to the preceding claim characterized in that the closed growing structure is: - a greenhouse, - a growing chamber, - a growing closet, or - a growing tent.

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