Dehydration device and assembly, and method for obtaining such an assembly

Abstract

The invention relates to a dehydration device comprising a drying device (6) placed in a chamber and suitable for reducing the partial water vapour pressure in a carrier fluid. The chamber includes a separate inlet and outlet, arranged so that the water-laden carrier fluid entering the chamber via the inlet comes into contact with or passes through the drying device (6) and exits via the outlet with a lower water content. The dehydration device also comprises an inlet interface (3) of the dehydration device suitable for being connected to a corresponding outlet interface (4) of a dehydration enclosure, an outlet interface (11) of the dehydration device suitable for being connected to a corresponding inlet interface (12) of the dehydration enclosure, and a flow management module (5) suitable for generating and controlling the flow of carrier fluid in the dehydration device, this flow management module (5) being configured to apply, at the outlet of the dehydration device, a pressure at least 500 millibars lower than atmospheric pressure, and to control the relative humidity in the carrier fluid at the outlet of the dehydration device.

Description

[0001] Dehydration device and assembly, method for obtaining such an assembly

[0002] The present invention relates to the field of dehydration and in particular that of dehydration installations.

[0003] Dehydration generally refers to the removal of water from a product. This process can have various objectives, for example, to allow a product to be stored for a long time, or to concentrate certain elements.

[0004] Dehydration includes in particular the processes of drying or desiccation under vacuum.

[0005] These processes include freeze-drying. Freeze-drying involves the desiccation of a previously frozen product by sublimation. Freeze-drying is carried out by maintaining the product at a low temperature under vacuum. In freeze-drying processes, the water extracted from the products is generally condensed by a system of cold plates and then removed from the freeze-drying installation.

[0006] Other vacuum dehydration processes are known.

[0007] Vacuum dehydration has several main advantages. Lowering the boiling point and therefore working at a lower temperature helps preserve the qualities of the dehydrated product. Dehydrating in the absence of oxygen or in the presence of little oxygen prevents the oxidation of certain molecules.

[0008] However, low pressures imply very large volumes of water vapor, which must therefore be "trapped". There are different ways to trap water: by physiosorption, chemosorption, condensation.

[0009] Vacuum dehydration processes generally involve the use of a condensation device, or may involve the use of a water trap containing an adsorbent material. A facility for implementing such processes using an adsorbent material generally comprises an enclosure that receives trays of products to be dehydrated and assemblies containing the adsorbent material. A vacuum in the enclosure causes evaporation of the water initially contained in the products and the water vapor thus produced is adsorbed by the adsorbent material. The main applications of the dehydration technologies targeted in the present invention relate to the dehydration of food products, cosmetic products, and pharmaceutical products, bio-sourced products (for example wood), or products used in the composition of such food, cosmetic or pharmaceutical products, etc.

[0010] Various dehydration devices have been known in the state of the art for a long time.

[0011] For example, document US2374232 discloses a vacuum dehydration device (in this case freeze-drying), using a desiccant material such as silica gel. The product to be dehydrated is placed in a container which is in communication with a chamber which contains the desiccant material, which allows free gas exchange and pressure balance between the container where the product is placed and the chamber which contains the desiccant material.

[0012] Document FR2805759 relates to a dehydration process in a similar system comprising at least one standard type solid / gas reversible adsorption reactor which contains, in an enclosure, an adsorbent such as zeolite, a tank containing a product to be adsorbed (for example placed on trays); and a fluid connection provided with a valve to allow communication between the enclosure and the tank and a pressure balance between the enclosure and the tank.

[0013] This document recalls in particular that a process for implementing such a device typically comprises the following three successive phases:

[0014] - an adsorption phase, during which the enclosure containing the adsorbent is placed in communication with a tank containing the product to be dehydrated;

[0015] - a regeneration phase, during which said enclosure containing the adsorbent is placed in communication with a condensation system, said enclosure is isolated from said tank, and said adsorbent is heated; and

[0016] - a cooling phase, during which said enclosure is isolated and said adsorbent is cooled.

[0017] The device and method presented in this document relate in particular to the conditions applied to the adsorbent, which can nevertheless be further optimized.

[0018] Document FR2868520 also discloses a zeolite dehydration installation in which the product to be dehydrated is positioned in a receptacle which is received in a compartment, the whole being placed in an enclosure. The objective is to place the adsorbent as close as possible to the dehydrated product, which, for a food, would allow its taste properties to be better preserved. When the products are dehydrated, the whole is removed from the enclosure for the regeneration of the zeolites. This manipulation is however complex, and increases the cycle times of the device.

[0019] Document WO2004 / 043574 discloses a drying system with a chamber and a drying device located upstream of a dehydration chamber. A drying device can also be placed downstream of the dehydration chamber, but only when it is in the regeneration phase, so that the water removed from the drying device during regeneration is carried along by the flow of humid air from the dehydration chamber. It is proposed in this document to operate the drying system at a pressure below atmospheric pressure of up to 400 millibars below atmospheric pressure (600 millibars absolute pressure).

[0020] Drying products at a pressure below atmospheric pressure promotes the evaporation of water from the products to be dried. However, this greatly increases the specific volume of water vapor released from the products.

[0021] The installations known to date are therefore not optimized in a global approach to the dehydration process, in order to preserve the properties of the product while allowing efficient implementation of the device.

[0022] The present invention aims to provide an optimized dehydration device.

[0023] Thus, the invention relates to a dehydration device comprising a chamber and a drying device adapted to reduce the partial pressure of water vapor of a carrier fluid when said carrier fluid is in contact with said drying device or passes through it, said drying device being placed in said chamber.

[0024] The chamber has a separate inlet and outlet arranged so that the water-laden carrier fluid entering the chamber through said inlet comes into contact with or passes through the drying device and exits through the outlet with a lower water content. The dehydration device also comprises:

[0025] - an input interface of the dehydration device adapted to be connected to a corresponding output interface of a dehydration chamber,

[0026] - an output interface of the dehydration device adapted to be connected to a corresponding input interface of the dehydration chamber,

[0027] - a flow management module, adapted to generate and control the flow of carrier fluid in the dehydration device, said flow management module being configured to apply, at the outlet of the dehydration device, a pressure of at least 500 millibars lower than atmospheric pressure, and to control the relative humidity in the carrier fluid at the outlet of the dehydration device.

[0028] The dehydration device comprises a carrier fluid compression device, adapted to raise the pressure of said carrier fluid between the inlet interface of the dehydration device and the drying device.

[0029] The device thus proposed is distinguished from known devices, in particular in the food sector, operating in batches ("batch" according to the English terminology more common in the field) by a drying device, for example a water trap, remote from the dehydration chamber. This allows, if necessary, regeneration of an adsorbent material present in the water trap directly in the chamber, without special handling and without immobilizing the dehydration chamber. This allows, for example, the chamber to be unloaded and reloaded with product to be dehydrated during the regeneration of the adsorbent material. In certain embodiments, this allows a new dehydration cycle to be launched in the dehydration chamber using a water trap other than the one whose adsorbent material is being regenerated.

[0030] It is notable that the present invention relates firstly to a dehydration device independently of the dehydration enclosure intended to receive the product to be dehydrated. This makes it possible in particular to use the dehydration device, thanks to the interfaces it comprises, to equip and update a pre-existing dehydration installation. In particular, any pre-existing dehydration tunnel can be used to form a dehydration system in accordance with the invention.

[0031] To the extent that the device offers vacuum dehydration, the flow management module includes a device with technology adapted to circulate the water vapor extracted from the products under vacuum: rotor pump type systems (see below) or compressor can be used.

[0032] Throughout this document, the term "vacuum" is understood to mean a pressure at least 500 millibars lower than atmospheric pressure, and preferably 700 millibars lower than atmospheric pressure. This allows the product to be dried at relatively low temperatures (typically below 70°C) and therefore less degradation of the heat-sensitive molecules in the product.

[0033] Thus, the flow management module also allows fine control of the dehydration conditions of the product being processed, in order to preserve the desired properties (for example taste).

[0034] In other words, since the flow management module is configured to control vacuum dehydration, a vacuum is applied to the outlet of the dehydration device. Vacuum dehydration can be carried out at low temperatures, which preserves certain qualities of the product being dehydrated.

[0035] However, imposing a very low pressure increases the specific volume of water vapor. This is why a drying device is proposed, within the framework of the present invention, downstream of the enclosure in which the product to be dried is placed, to reduce the partial pressure of water vapor in the carrier fluid.

[0036] However, low pressure has a strong negative impact on the ability of the drying device to reduce the partial pressure of water vapor in the carrier fluid. Typically, such a low pressure level limits the adsorption capacity of materials such as silica gels or zeolites. Therefore, the invention provides a device for compressing the carrier fluid between the dehydration chamber and the drying device.

[0037] Concerning this device for compressing the carrier fluid, once a dehydration system is constituted by connecting a dehydration chamber to the dehydration device, it allows (for example under the control of the management system) to impose two pressure levels in the system. A significant depression, of at least 500 millibars with respect to atmospheric pressure, is imposed at the outlet of the dehydration device, and therefore in the dehydration chamber where the product to be dehydrated is located. A lower depression, or ideally a pressure close to atmospheric pressure or even higher than it, is obtained at the inlet of the drying device.

[0038] This promotes the reduction, by the drying device, of the water content (partial pressure of water vapor) in the carrier fluid entering the dehydration device.

[0039] Thus, the dehydration device allows the obtaining of different and optimized pressure conditions on the one hand for the dehydration of a product, and on the other hand for the reduction of the water content of the carrier fluid, in particular using a water trap.

[0040] The carrier fluid compression device comprises a volumetric pump.

[0041] A suitable positive displacement pump may be, for example, a claw pump or a lobe pump, in particular a pump generally referred to by the English expressions "roots pump" or "booster pump" comprising two bilobed rotors which rotate in a synchronized manner and which is adapted to operate under vacuum. Such a pump makes it possible to control the suction flow rate at the inlet of the device.

[0042] In the dehydration device, a buffer tank, forming a volume for receiving the carrier fluid, can be interposed between the carrier fluid compression device and the inlet of the chamber.

[0043] The buffer tank allows for the formation of a reserve of steam at overpressure compared to the pressure in the dehydration chamber. This reserve allows for better control of the pressure in the drying device, and allows for the optimization of the drying device operation.

[0044] The flow management module may further be adapted to control the mass flow rate of carrier fluid exiting the dehydration device through its outlet interface.

[0045] The flow management module can further be adapted to control the temperature of the carrier fluid exiting the dehydration device through its outlet interface.

[0046] The chamber outlet can be fluidically linked to the outlet of the dehydration device, via the flow management module.

[0047] Thus, the carrier fluid is fully or partially recirculated, that is to say that the fluid leaving the dehydration chamber is returned to said dehydration chamber after its water content has been lowered by the drying device. The establishment of this closed, or partially closed, loop allows better conservation of the molecules of interest (typically aromatic) in the dehydrated products.

[0048] The drying device may comprise an adsorbent material, adapted to adsorb water present in the carrier fluid.

[0049] The adsorbent material used may include a zeolite. Zeolites are known for their water adsorption performance. The zeolite used may include a 4 angstrom zeolite (or 4A zeolite), i.e., a type of aluminosilicate crystal with average pores measuring 4 angstroms (0.4 nm).

[0050] Alternatively other adsorbent materials may be used, including

[0051] - activated alumina (or aluminum oxide);

[0052] - silica gel;

[0053] - activated carbon;

[0054] - a carbon molecular sieve (often referred to as CMS)

[0055] - an absorbent

[0056] - an absorbent polymer (including a bio-sourced polymer).

[0057] The drying device may include a system for condensing the water vapor present in the carrier fluid, for example a cold plate device. The flow management module may also include a vacuum source to reduce the pressure at the outlet interface of the dehydration device.

[0058] The sweeping means thus makes it possible to apply the pressure (i.e., in practice, the vacuum level) desired for dehydration. The vacuum evaporation thus achieved requires a low energy input. The vacuum source may comprise a vacuum pump or a vacuum network. The vacuum input is advantageously carried out, if necessary, according to a setpoint. This setpoint can in particular be adapted according to the nature of the dehydrated product.

[0059] The invention also relates to a dehydration system comprising a dehydration device as described above and a dehydration chamber, the dehydration chamber being equipped with an inlet interface in the dehydration chamber fluidly connected to the outlet interface of the dehydration device and an outlet interface of the dehydration chamber fluidly connected to the inlet interface of the dehydration device.

[0060] The invention therefore also relates to the complete system, comprising the dehydration chamber. This chamber may in particular be adapted to the dehydration of food (or other) products by vacuum evaporation. The dehydration chamber may comprise a set of shelves for receiving trays adapted to contain a product to be dehydrated.

[0061] This configuration optimizes the ratio between the evaporation surface exposed by the product and the volume of the dehydration chamber.

[0062] The carrier fluid used can be, for example, air or nitrogen.

[0063] The use of nitrogen prevents oxidation of the product, which is being dehydrated. When the system uses carrier fluid recycling, the system's nitrogen consumption remains limited. The use of carbon dioxide (CO2) is also possible.

[0064] The dewatering system may comprise a plurality of drying devices, each drying device comprising an adsorbent material adapted to adsorb water present in the carrier fluid, the system being configured such that one of the drying devices is used to reduce the water content in the carrier fluid, while the adsorbent material of another of the drying devices is regenerated, and / or another drying device is used to dry the carrier fluid entering the dewatering enclosure.

[0065] The device can thus operate by alternating adsorption phases and regeneration phases on different drying devices, for example different water traps. This makes it possible to significantly increase the usage time of the dehydration chamber for dehydrating products.

[0066] The invention finally relates to a method for obtaining a dehydration system as described above, by transforming a pre-existing dehydration installation. This method comprises the following steps:

[0067] - supply of a dehydration installation comprising a dehydration chamber;

[0068] - supply of a dehydration device as described above,

[0069] - removal of internal dehydration equipment from the dehydration chamber,

[0070] - installation on the dehydration chamber of an inlet interface of the dehydration chamber and an outlet interface of the dehydration chamber, adapted to be connected respectively to the outlet interface of the dehydration device and to the inlet interface of the dehydration device,

[0071] - connecting the inlet interface in the dehydration chamber to the outlet interface of the dehydration device and connecting the outlet interface of the dehydration chamber to the inlet interface of the dehydration device.

[0072] The device proposed in the invention, thanks to its drying device(s) remote from the dehydration chamber and thanks to its modular design, thus allows for the modernization of pre-existing installations. This allows, for example, the conversion of freeze-drying tunnels into a dehydration system in accordance with the present invention.

[0073] Other features and advantages of the invention will become apparent in the description below.

[0074] In the attached drawings, given as non-limiting examples: Figure 1 represents, according to a principle diagram, a dehydration device and a dehydration system in accordance with embodiments of the present invention, Figure 2 represents, according to a simplified industrial diagram, a dehydration system in accordance with an embodiment of the invention.

[0075] Figure 1 shows, according to a block diagram, a dehydration system according to an embodiment of the present invention. The dehydration system comprises a dehydration device 1, which is primarily the subject of the present invention, and a dehydration chamber 2 to which the dehydration device 1 is connected.

[0076] The dehydration device 1 comprises an inlet interface of the dehydration device 3, through which a carrier fluid containing water in gaseous form enters the dehydration device for the purpose of drying it. The inlet interface of the dehydration device 3 is intended to be connected to an outlet interface of the corresponding dehydration enclosure 4. The carrier fluid is a gas, which may be air or advantageously nitrogen.

[0077] The inlet interface of the dehydration device 3 and the outlet interface of the dehydration chamber 4 provide a fluid connection between the dehydration chamber 2 and the dehydration device 1. These interfaces can thus take various forms; they can be screwed, flanged, welded, etc.

[0078] The dehydration device comprises a flow management module 5. The function of the flow management module 5 is in particular to ensure the circulation of the carrier fluid in the dehydration system, and thus to control the relative humidity level in the dehydration chamber 2. It also makes it possible to control the flow rates and the pressure in the drying device 6 (described below).

[0079] In the example shown, the flow management module itself consists of two interoperating modules, namely a circulation module 7 and a scanning module 8.

[0080] In the example shown, the circulation module 7 is positioned downstream of the inlet interface of the dehydration device 3. The circulation module aims firstly to generate and control the flow of carrier fluid in the dehydration device. In this example, it comprises mechanical equipment, such as a rotor pump (roots pump), or any other equipment suitable for operating under high vacuum and managing the flow of the carrier fluid at the outlet of the dehydration chamber and consequently at the inlet of the drying device. This equipment also forms a device for compressing the carrier fluid. The compression device makes it possible to raise the pressure of the carrier fluid between the inlet interface of the dehydration device and the drying device.

[0081] Throughout this document, the concept of upstream and the concept of downstream is understood according to the direction of flow of the carrier fluid.

[0082] Optionally, a buffer tank 9 can be arranged between the mechanical equipment of the circulation module 7 and the drying device 6. The buffer tank 9 allows better control and temporal smoothing of the operating conditions of the drying device 6 (pressure and temperature).

[0083] The use of mechanical equipment also has the advantage of allowing recompression of the carrier fluid before it enters the drying device. However, alternatively, in an embodiment where the carrier fluid is not (or not totally) recycled at the inlet of the dehydration chamber, as explained below, the circulation module can be formed by a device for controlling the pressure differential between the outlet and the inlet of the dehydration device. In this case, it is essentially a pressure play between a vacuum source and a vent that can drive the flow of carrier fluid into the dehydration chamber 2 and into the dehydration device 1.In the case where the carrier fluid is not recycled in full, or, in general, if it is necessary to provide a supply of carrier fluid into the dehydration system, the carrier fluid introduced may be air or another gas dried in a second drying device 6' of the dehydration device.

[0084] In all embodiments, the circulation module may comprise a device for determining the relative humidity of the carrier fluid entering the dehydration device 1, for example a humidity sensor, and use this information to control the flow rates in the dehydration system.

[0085] The dehydration device comprises, as mentioned above, a drying device 6, intended to capture the water present in the carrier fluid coming from the dehydration enclosure.

[0086] The drying device 6 is generally arranged in a chamber of the dehydration device.

[0087] The drying device 6 makes it possible to reduce the quantity of water present in the carrier fluid which is present around the drying device or which passes through it.

[0088] The drying device may thus comprise a cold plate device which causes the condensation of water present in the form of vapor in the carrier fluid on the surface of said cold plates.

[0089] The drying device may alternatively comprise a material suitable for adsorbing a significant quantity of water, called adsorbent material, under appropriate temperature and pressure conditions.

[0090] Zeolites are known for their high capacity to adsorb water, without taking up volume, and can therefore be used as an adsorbent material for a water trap.

[0091] The adsorbent material may be installed in a basket or cassette arranged in the chamber containing the drying device 6, so as to be brought into contact with, or even to be crossed if necessary, by the carrier fluid loaded with vapor which enters the water trap.

[0092] The flow control module 5 further comprises a scanning module 8.

[0093] The scanning module 8 makes it possible in particular to control the quantity of air entering the dehydration chamber 2.

[0094] It also allows certain characteristics to be controlled, namely pressure and / or temperature. For example, it allows the desired vacuum level to be maintained by a vacuum top-up using a vacuum source 10, for example a vacuum pump or a vacuum unit (via a vacuum network).

[0095] The dehydration device 1 comprises a dehydration device outlet interface 11, through which the dried carrier fluid exits the dehydration device to be used for drying or evaporating a product in a dehydration chamber.

[0096] The output interface of the dehydration device 11 is intended to be linked to an input interface of the corresponding dehydration enclosure 12.

[0097] The outlet interface of the dehydration device 11 and the inlet interface of the dehydration chamber 12 provide a fluid connection between the dehydration device 1 and the dehydration chamber 2.

[0098] Just like the inlet interface of the dehydration device 3 and the outlet interface of the dehydration chamber 4, these interfaces can take various forms, they can be screwed, flanged, welded, etc.

[0099] The means described above of the dehydration device allow it to operate to dehydrate a product present in a dehydration chamber 2 linked to said device, described in more detail below. However, when the drying device is a water trap, the adsorbent material having adsorbed a significant quantity of water must be regenerated by making it desorb the water it contains, so that it recovers its adsorption capacity.

[0100] The dehydration device includes a regeneration module 13 for this purpose.

[0101] The regeneration module 13 makes it possible to place the adsorbent material of the water trap in temperature and pressure conditions suitable for its regeneration. The regeneration module can in particular be configured to carry out regeneration under vacuum.

[0102] The regeneration module 13 is selected and configured according to the general operating mode of the dehydration device. This can advantageously operate in vacuum-assisted adsorption, in particular in vacuum swing adsorption (VSA), in which a low pressure is imposed during regeneration and a relatively higher pressure is imposed during adsorption.

[0103] The dehydration device thus developed is connected (via the inlet interface of the dehydration device 3 and the outlet interface of the dehydration device 11) to a dehydration enclosure 2 in order to form a dehydration system in accordance with the invention.

[0104] The dehydration chamber 2 may be purposely produced, or may alternatively be a pre-existing chamber, for example a freeze-drying tunnel that one would wish to develop into a system in accordance with the present invention.

[0105] In such a system, the dehydration chamber 2 is adapted to receive the products to be dehydrated. It is adapted to operate at the target pressure during the dehydration of the products.

[0106] A generally tubular shape is thus particularly well suited to systems operating at a high vacuum level. This enclosure can have large dimensions to allow the dehydration of products on an industrial scale. For example, a tubular enclosure with an internal diameter of approximately 2.5 m and an internal length of 5 m can be used. These dimensions are given as an example only. Systems with a chamber with a much larger volume can be considered.

[0107] Enclosure 2 includes a suction pipe allowing the evacuation of the air-laden carrier fluid (typically air and water vapor). The suction pipe thus includes the outlet interface of enclosure 4.

[0108] The enclosure 2 comprises an inlet pipe for ensuring the supply of carrier fluid to ensure a sweeping flow in the enclosure 2. The inlet pipe thus comprises the inlet interface of the enclosure 12.

[0109] The arrangement of the suction pipe and the inlet pipe (in particular their connection to the enclosure) is chosen to promote uniform sweeping of the interior volume of enclosure 2.

[0110] The enclosure is of course equipped with a door allowing the loading and unloading of the products to be dehydrated.

[0111] The products can advantageously be loaded onto trays or bins, suitable for food contact where appropriate. The products processed can be in solid or liquid form (including pasty). The configuration of the enclosure tends to maximize the exchange surface of the products with the carrier fluid, for example with air.

[0112] In order to promote their dehydration, in a dry carrier fluid, the products to be dehydrated can be heated (nevertheless, under vacuum, dehydration is carried out at low temperature, which allows certain qualities of the treated products not to be altered).

[0113] Finally, in addition to the low dehydration temperature and the complete or partial recycling of the carrier fluid, a molecular preservation module 14 can be interposed in the flow of carrier fluid leaving the enclosure. The molecular preservation module 14 comprises a molecular sieve so that only water in gaseous form leaves the enclosure with the carrier fluid, and not certain molecules of interest (aromatic compounds in particular) which are thus maintained in the environment of the product being dehydrated. The molecular preservation module 14, which is optional, can therefore be located at any point in the flow between the dehydration enclosure 2 and the flow management module 5: in the dehydration enclosure 2, between the dehydration enclosure 2 and the dehydration device 1, or at the inlet of the dehydration device 1.

[0114] Figure 2 represents, according to a simplified industrial diagram (most of the valves, sensors, venting, and peripheral systems being omitted), an example of a dehydration system in accordance with an embodiment of the invention.

[0115] The system comprises a dehydration chamber 2 in which the product to be dehydrated is placed.

[0116] A heating circuit 15 associated with a thermoregulator system 16 makes it possible to heat the product present in the dehydration chamber 2, using a heat transfer fluid.

[0117] The dehydration device comprises, in the example shown, three drying devices, namely three water traps 6, 6', 6”. Each water trap comprises a bed of 4 angstrom zeolite as adsorbent material. The carrier fluid used is air, under low pressure. The flow is created in the device using a rotor pump of the circulation module 7 of the flow management module. The circulation module 7 is placed, in the example shown, downstream of the water traps 6, 6', 6”. The dehydration device is configured, with regard to these inlet pipes 17 (which are linked to the outlet interface of the enclosure 2), so that each water trap may or may not be crossed by the carrier fluid and the water vapor from the dehydration enclosure 2. A valve is thus provided at the inlet of each water trap to authorize or prohibit the entry of the carrier fluid loaded with water vapor.

[0118] In particular, only one of the water traps can be used to adsorb the water present in the carrier fluid coming from enclosure 2. By passing through a water trap, the carrier fluid is dried by adsorption of the water vapor it contains in the zeolite of the water trap passed through.

[0119] The outlet pipes of the water trap are fluidically connected to the equipment of the circulation module 7 adapted to create the flow of carrier fluid. The carrier fluid then circulates towards the scanning module 8, via a return conduit 18.

[0120] The scanning module 8 controls the flow of carrier fluid directed towards the inlet interface of the enclosure 2 via an outlet pipe 19. If a vacuum supplement is necessary, the pressure can be reduced using the vacuum source 9, here in the form of a vacuum pump.

[0121] If a supply of dry carrier fluid is necessary, this supply can be achieved via a supply branch 20 which takes air from the atmosphere through a filter 21, and dries it in one of the water traps 6, 6', 6” of the dehydration device, different from the water trap then used to dry the carrier fluid from the dehydration chamber 2.

[0122] Thus, alternatively to the device shown in Figure 2, all of the dry carrier fluid introduced into the enclosure can come from the supply branch 20, while there is no return conduit 18 and the circulation module comprises a vacuum pump (as equipment for generating the flow) which discharges the dried carrier fluid into the atmosphere.

[0123] Finally, while one of the water traps 6, 6', 6” is used to recover the water from the product contained in the dehydration chamber, and optionally another is used for a supply of dry carrier fluid, a water trap can be simultaneously regenerated. For this, the regeneration module 13 ensures the heating of the air sucked into the water trap during regeneration, while the vacuum source allows the water trap to be depressurized in order to carry out a regeneration under vacuum.

[0124] The invention thus developed therefore makes it possible to firstly form a dehydration device, suitable for forming a dehydration system when associated with a suitable dehydration chamber. The use of a scanning module makes it possible to control the dehydration conditions of the product being treated, in order to preserve the desired properties (for example taste). It also makes it possible to optimise the conditions of adsorption of water by the adsorbent material of the water trap. Finally, it allows energy optimisation of the dehydration process. The modular approach proposed in the invention, as well as the offsetting of the water traps from the chamber (allowed by circulation means suitable for creating a flow under low pressure), also makes it possible to envisage upgrading existing dehydration installations to a system in accordance with the present invention.

Claims

Claims 1. Dehydration device comprising - a chamber and a drying device (6) adapted to reduce the partial pressure of water vapor of a carrier fluid when said carrier fluid is in contact with said drying device (6) or passes through it, said drying device (6) being placed in said chamber, characterized in that the chamber has a separate inlet and outlet and arranged so that the water-laden carrier fluid entering the chamber through said inlet comes into contact with or passes through the drying device (6) and leaves through the outlet with a lower water content, the dehydration device also comprising: - an input interface of the dehydration device (3) adapted to be connected to a corresponding output interface of a dehydration chamber (4), - an output interface of the dehydration device (11) adapted to be connected to a corresponding input interface of the dehydration chamber (12), - a flow management module (5), adapted to generate and control the flow of carrier fluid in the dehydration device, - said flow management module (5) being configured to apply, at the outlet of the dehydration device, a pressure of at least 500 millibars lower than atmospheric pressure, and to control the relative humidity in the carrier fluid at the outlet of the dehydration device, and - a device for compressing the carrier fluid, adapted to raise the pressure of said carrier fluid between the inlet interface of the dehydration device and the drying device (6).

2. Dehydration device according to claim 1, in which the device for compressing the carrier fluid comprises a positive displacement pump.

3. Dehydration device according to claim 1 or claim 2, in which a buffer tank (9), forming a volume for receiving the carrier fluid, is interposed between the device for compressing the carrier fluid and the inlet of the chamber.

4. Dehydration device according to one of the preceding claims, in which the flow management module (5) is adapted to control the mass flow rate of carrier fluid exiting the dehydration device through the dehydration device outlet interface (11).

5. Dehydration device according to one of the preceding claims, in which the flow management module (5) is adapted to control the temperature of the carrier fluid leaving the dehydration device via the outlet interface of the dehydration device (11).

6. Dehydration device according to one of the preceding claims, in which the outlet of the chamber is fluidically linked to the outlet of the dehydration device, via the flow management module (5).

7. Dehydration device according to one of the preceding claims, in which the drying device (6) comprises an adsorbent material, adapted to adsorb water present in the carrier fluid.

8. Dehydration device according to one of the preceding claims, in which the drying device (6) comprises a system for condensing the water vapor present in the carrier fluid, for example a cold plate device.

9. Dehydration device according to one of the preceding claims, in which the flow management module (5) comprises a vacuum source (10) making it possible to reduce the pressure at the outlet interface of the dehydration device.

10. Dehydration system comprising a dehydration device according to one of the preceding claims and a dehydration enclosure (2), the dehydration enclosure (2) being equipped with an inlet interface in the enclosure (12) fluidly connected to the outlet interface of the dehydration device (11) and an outlet interface of the enclosure (4) fluidly connected to the inlet interface of the dehydration device (3).

11. Dehydration system according to claim 10, in which the dehydration enclosure (2) comprises a set of shelves for receiving trays adapted to contain a product to be dehydrated.

12. A dehydration system according to claim 10 or claim 11, wherein the carrier fluid is air or nitrogen.

13. A dehydration system according to one of claims 10 to 12, comprising a plurality of drying devices (6, 6', 6”), each drying device (6) comprising an adsorbent material adapted to adsorb water present in the carrier fluid, the system being configured so that one of the drying devices is used to reduce the water content in the carrier fluid, while the adsorbent material of another of the drying devices is regenerated, and / or another of the drying devices is used to dry the carrier fluid entering the dehydration chamber.

14. Method for obtaining a dehydration system according to one of claims 10 to 13 by transforming a pre-existing dehydration installation, the method comprising the following steps: - supply of a dehydration installation comprising a dehydration chamber (2); - provision of a dehydration device according to one of claims 1 to 10, - removal of internal dehydration equipment from the dehydration chamber (2), - installation on the dehydration chamber (2) of an inlet interface of the dehydration chamber (12) and an outlet interface of the dehydration chamber (4), adapted to be connected respectively to the outlet interface of the dehydration device (11) and to the inlet interface of the dehydration device (3), - connecting the inlet interface of the dehydration chamber (12) to the outlet interface of the dehydration device (11) and connecting the outlet interface of the dehydration chamber (4) to the inlet interface of the dehydration device

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