DK2482017T3

DK2482017T3 - Plant for the drying of the products

Info

Publication number: DK2482017T3
Application number: DK12152906.9T
Authority: DK
Inventors: Laurent Savary
Original assignee: Florette Holding
Priority date: 2011-01-31
Filing date: 2012-01-27
Publication date: 2015-06-15
Also published as: FR2971046A1; EP2482017B1; EP2482017A1; FR2971046B1; PT2482017E; PL2482017T3; ES2538836T3

Description

Domain of the invention [0001] The invention pertains to an installation for drying the surface of products to eliminate surface humidity, and in particular an installation for drying semifinished vegetal products to remove superficial humidity in view of packaging these products; the moist products circulate through the said installation.

State of the art [0002] There are currently various different procedures and installations for drying the surface of vegetal products such as cut and washed salad leaves.

[0003] One of the procedures consists of spinning the products in a centrifugal extractor. This procedure has the advantage of not raising the temperature of the products, but also the disadvantage that it exerts mechanical stresses on the products, and can be done only in batches, i.e. in a non-continuous manner. This procedure is not suitable for relatively fragile products because centrifugal extraction involves the products being subjected to mechanical stresses, which damages, at least partially, the fragile parts of the plants; this is likely to cause their appearance and organoleptic qualities to deteriorate.

[0004] There is also a procedure for drying using a dry and hot air stream, but this procedure, which presents the advantage of the products not being subjected to mechanical stresses which may damage them, has the disadvantage of needing a relatively long residence time of about 20 minutes. To ensure that this procedure can be implemented in a continuous manner, the products must remain in the drying enclosure for this period. This necessitates a long stay in the drying installation and thus requires an installation with a very big volume.

[0005] This procedure also has the disadvantage that it heats up the products, even if only slightly, so that they must then again be cooled for packaging and conservation at a temperature that is generally 4°C. This results in wastage of energy.

[0006] In accordance with document US 1 928 993, there is also an apparatus for drying fruits. Such an apparatus is not appropriate for drying fragile foodstuffs such as salad leaves, since the products are transported using rollers fitted with overhanging digits.

[0007] The document US 5913590 describes an installation for drying wet vegetal products, such as pieces of salad leaves.

Purpose of the invention [0008] The purpose of this invention is to develop an installation to remove superficial humidity from flat products that are irregularly shaped and fragile, such as vegetal products after washing, by carefully handling their fragile structure and by quickly and effectively removing superficial moisture.

Presentation and advantages of the invention [0009] To this end, the purpose of the invention for products such as pieces of vegetal products is to remove superficial moisture, since this installation is characterised by the fact that it contains at least one drying module, which includes: • a support surface that receives the products to be dried, • a contact zone for the products to be dried, located between the support surface and a drying surface fitted with a layer of microfibre strips in the contact zone, • a moisture extractor after the contact zone, placed according to the direction of movement of the drying belt, to compress the drying surface and suck out the moisture.

[0010] The drying installation in which the products pass through the contact zone ensures a significant flow while carefully handling the fragile products, since the contact zone between the microfibre strips of the drying surface and the surface of the products to be dried uses almost no pressure, comparable to a light touch; this contact is sufficient to absorb the surface moisture from the product. The absorption is almost instantaneous in the contact zone between the microfibre strips and the surface of the products. The light touch also has the advantage of allowing the strips to reach the cavities or recesses that are often undercut, like those of a wet surface of a vegetal product such as a piece of a salad leaf, all the more so when the product to be dried is not necessarily flat or does not need to be kept flat or placed in a flat position, i.e. held against the support surface. This operation does not affect the intrinsic moisture of the product. Since the product is neither heated even slightly nor subjected to mechanical forces which increase the risk of its hardening, it retains all its inherent moisture and, consequently, its freshness. In a particularly advantageous manner, the drying surface is a drying belt. Thus: • the contact zone for the products to be dried is located between the support surface and a drying surface constituted by a belt fitted with a layer of microfibre strips in the contact zone and • the moisture extractor after the contact zone, placed according to the direction of movement of the drying belt, to compress the drying band and suck out the moisture.

[0011] Another advantage is that the support surface is a conveyor belt which circulates at the same speed as the drying belt in the contact zone; this ensures that the products are not subjected to any friction owing to the relative speed in the contact zone, since the products cross the contact zone at the same tangential speed as that of the microfibre strips of the drying belt. This contact, even though it is very light and quick, allows highly efficient elimination of superficial moisture.

[0012] The drying belt is a detachable sleeve which is worn on a rotating cylin- der, which is particularly advantageous. This allows the drying belt to be removed in order to treat it independently of its drying through extraction of moisture, upstream of the contact zone.

[0013] In accordance with another advantageous characteristic, the moisture extractor is a perforated cylinder, which turns when in contact with the drying belt and compresses it in a compression zone, where the perforated cylinder is connected to a source of negative pressure to extract the moisture squeezed by the drying belt contained therein.

[0014] In case of products that are relatively flat, such as pieces of vegetables from a wash bath, it is particularly advantageous that the drying installation consists of two paired drying modules which constitute the support surface for one another, and that a contact zone is located between them, through which the products to be dried will pass. Thanks to the highly flexible and deformable structure of the drying belts, the connecting surface of the two belts is not a plane surface similar to a tangent plane, but a flexible zone of a certain thickness which increases the softness with which the pieces of vegetables passing through are maintained. Thus, this installation, which has two paired modules, has the advantage of drying both surfaces of the products simultaneously, and the products are maintained in the installation through simple contact in the gap between the two contact zones of each driven drying belt.

[0015] The drying belts connected to the two paired modules are sleeves mounted on rotating cylinders, which is particularly advantageous. Even though products that are flat and irregularly shaped but fragile pass through the reduced interval between the cylinders, they are softly maintained by the microfibre strips, which contact the product, follow the irregularity of the surfaces and absorb the superficial moisture from inside the recesses of the surface irregularities.

[0016] In accordance with another method of execution which is particularly advantageous for the flow and speed of drying of especially fragile products, each drying module is a conveyor with a conveyor belt fitted with a layer of microfibre strips, and the modules are assembled roughly parallel to each other. There is a lower module and an upper module above it, the opposing sides of which form a contact zone in the shape of a corridor, and also a device for controlling the travel speed of the conveyor belts. All sides other than those defining the drying corridor are fitted with a moisture extractor.

[0017] These belt conveyor drying modules allow a particularly long contact time between the layer of microfibre strips and the surface of the products, which allows very effective drying, especially in case of products of extremely contorted shapes which may be difficult to dry with a very brief contact with the microfibre strips layer.

[0018] Due to the length of the contact zone, i.e. the drying corridor, it is simple to adapt the height of the drying corridor to the type of product, all the more so since this adjustment can be made continuously and the opposing sides of both conveyor belts with their layers of microfibre strips are not necessarily rectilinear and may have a certain inclination, which modifies the profile of the drying corridor along the length of the path travelled by the products.

[0019] This variation may be executed continuously with increasing or decreasing intensity. It may also alternate between phases of increasing and decreasing intensity to promote the change of the location of microfibres compared to the surface of the products.

[0020] In accordance with the invention, the discrepancy between both modules is adjustable to define the height of the drying corridor, which is not necessarily uniform, as has been indicated.

[0021] Lastly, the travel speed of the conveyor belts is controlled by a control device. This travel speed can be the same for both conveyor belts to ensure that the products remain technically immobile in relation to the conveyor belts for the duration of their residence in the drying corridor. But according to a vari ant, the speed of each conveyor belts is different, preferably slightly different, to ensure that the entire surface of the products is put under stress, either in the drive direction or the restraint direction, thus creating slight relative movement between both conveyor belts and between the two layers of microfibre strips of the drying module.

[0022] In accordance with another advantageous characteristic, several conveyor belt drying modules are installed in series, either in line or one above the other, to ensure a more gradual and softer drying of particularly fragile products, or for handling large product flows.

[0023] Beneficially, it is constituted by a succession of elementary installations, each consisting of a drying module formed by a conveyor with a conveyor belt fitted with a layer of microfibre strips fitted substantially parallel to one another, a lower and upper module which form a drying corridor, a control device which controls the travel speed of the conveyor belts of each drying module and a guide to convey the products from the outlet of an elementary installation to the input of the next elementary installation; these installations, fitted in series, are placed in a line or one above the other.

[0024] Generally, the drying installation that has been defined above allows effective drying using a simple means of execution and also allows a particularly easy maintenance for food applications such as drying of leaves or parts of vegetables.

Drawings [0025] This invention shall be described in a more detailed manner using an installation for drying flat products represented in the drawings in the annexe, in which: • figure 1 is a schematic cross section of a drying module for the products, • figure 2 shows a particular method of execution of the module of an installation for drying the products, • figure 3 is a schematic cross section of a drying module for the products consisting of two paired drying modules, • figure 4 is a schematic view of another method of execution of an installation for drying, consisting of two belt conveyors to dry both surfaces of the products, • figure 5 is a schematic view of an installation consisting of two parts mounted in series and each one consisting of one installation as shown in figure 4, in line, • figure 6 shows another variant of installations combined in series, with the superposition of two elementary installations as shown in figure 4.

Description of the methods of execution of the invention [0026] In accordance with figure 1, the purpose of the invention is to create an installation for drying 1 irregularly shaped wet surfaces with cavities and bumps, flat products such as leaves or pieces of plant leaves, fragile products that have wet surfaces after having been treated upstream, for example in a wash bath or watering zone. These products P arrive on a support surface 100 and then go into the drying module 200 of the installation. This drying module 200 consists of a drying surface which in this example is a drying belt 210, driven in the direction of arrow A; it then passes over the guiding cylinders 220, 221, defining the path of the belt and onto a support 222, which defines, with the support surface 100 on the opposite side, a contact zone ZC for the products to be dried P. The driven drying belt 210 is a belt fitted with a layer of microfibre strips 212; the strips move freely from the support surface 211 of the belt. Upstream of the contact zone ZC, the belt 210 passes over a support surface constituted by a rotating cylinder 213 and is connected to a moisture extractor which has a suction zone AZ, in the drying interval through which the drying belt 210 fitted with microfibre strips passes. Then, the belt 210 follows the circulation path crossing a treatment installation 260 - for example an ultraviolet chamber or treatment gas distribution chamber - to eliminate any possible germs on the belt, then the belt returns to the contact zone ZC.

[0027] The moisture extractor 250 consists of a perforated rotating cylinder 251, inside which is a suction chamber 252, which defines a negative pressure sector 253 at the level of the suction zone ZA of the perforated cylinder 251 opposite the pressure cylinder 213 to put the openings of the perforated cylinder 251 under negative pressure and thus suck out the moisture squeezed by the microfibre strip layer 212 so that the drying belt 210 leaves this ZA interval in a dry condition.

[0028] Figure 2 shows another drying installation 1A with a particular method of execution 200A of the drying module 200 of figure 1. In this method of execution 200A, the driven drying belt 21OA is worn on a cylinder 220A which is driven in rotation in the direction of arrow A. The general parts already described in figure 1 are used in this method of execution but are not represented in figure 2.

[0029] The pressure cylinder of the suction zone ZA with the moisture extractor 250A is replaced here by the cylinder 220A on which the sleeve constituting the drying belt 21 OA is worn. This sleeve 21 OA is preferably fitted in a detachable manner on the cylinder 220A, which allows it to be replaced from time to time for thorough cleaning, treatment or even replacement of sleeves whose strips 212A are worn.

[0030] In this example, the support surface 100A is constituted by a fixed surface. But this fixed surface 100A can also be constituted, for example, by a conveyor belt such that the products to be dried P do not undergo any differential speed in their passage in the contact zone ZC with the driven drying belt 201 A, since the tangential speeds are the same.

[0031] Figure 3 shows another method of execution of an installation for drying products 1B. This method of execution is different from the previous methods of execution in that it includes two drying modules 200A and 200B which are paired and are, in particular, identical. The surface of one of the modules 200A and 200B is always constituted by the drying belts 21 OA and 21 OB of the other module. In this particular example, the drying belts 21OA and 21 OB are worn on cylinders 220A and 220B which are driven in rotation, defining an interval between them through which the products P pass. The two modules 200A and 200B are installed symmetrically with respect to a vertical median plane, as per the orientation shown in figure 3. The products P are fed into the machine using a ramp 270 which pours the products P onto the surface of the drying belts 21 OA and 21 OB of one of the cylinders 220A or 22B or directly into the interval. The products P are delicately taken up by the strip layers 212A and 212 B which are more or less in relief owing to the rotation of the two cylinders 220A and 220B, and then pass with almost no pressure into the interval between the two cylinders, with only the contact of the two microfibre strips of the layers 212A and 212B which absorb the moisture from both surfaces of the products P. The dried products P exit the contact zone and reach a drainage mat 271.

[0032] In accordance with figure 4, another method of execution of an installation for drying 1C flat products with irregular and fragile structures such as pieces of leaves of vegetables which are moist, as in the installations shown above, consists of two drying modules 300A and 300B of an analogous structure, with conveyors having their belts fitted each with a microfibre strip layer. The conveyors are installed facing one another horizontally or substantially horizontally in the example show, and form a drying corridor CS where the products (P) to be dried are placed on the belts and transported.

[0033] The functioning of the installation 1C is controlled by a control station 10, which controls the drying modules 300A and 300 B and the speed of the transport and drying V1 and V2 as well as other parameters such as the discrepancy (e) between the two conveyors defining the interval, depending on the nature of the products to be dried. It also controls the functioning of the moisture extractors 350A and 350B and the treatment devices 360A and 360B of the drying belt (drying surface) of each drying module 300A and 300B.

[0034] In more detail:

The lower drying module 300A constitutes, through its upper run, the support surface and the transport surface on which the products P arrive. In brief, it consists of a conveyor 301A with a conveyor belt 302A with a microfibre strip layer 312A passing over both deflector cylinders 303A and 304A of which at least one (304A) is a driving cylinder fitted with a motor 305B. The upper run of the conveyor belt 302A defining the drying corridor CS has a support 306A such as a sliding plate, an air cushion plate, a series of rollers or even lateral guides for the transversal bar heads (not shown) integrated in the conveyor belt 302A, to guide it and support it so as to define the drying corridor CS.

The conveyor belt 302A circulates in the indicated direction and speed V1. The return run passes through a moisture extractor 350A, shown very briefly and including one or several extraction cylinders 351A and 352A. It also includes a treatment installation 360A, for example, an ultraviolet ray device to disinfect the return run.

The lower run has a support or guide 307A such as a sliding plate, an air cushion plate, a series of rollers or lateral guides for the transversal bar heads integrated in the conveyor belts, and it is supported against the cylinders 351A and 352A of the moisture extractor 350A by a pressure cylinder 311A and 312A connected to each extraction cylinder 351A and 352A.

The moisture extractor 350A is preferably movable with respect to the return side as shown in the diagram. This mobility is achieved through an actuator 353A, which is connected to the control centre 10 to execute a back-and-forth movement VV in relation to the belt 302A and to ensure that the extraction cylinders 351A and 352A, which have a similar structure to that of the cylinders 250 and 250A shown in figures 1 -3, do not only roll onto the microfibre strip layer 312A but combine with this rolling movement a sliding movement in the opposite direction, in order to increase the effectiveness of the moisture extraction. In case of movement of the extraction cylinders 351A and 352A, the pressure cylinders 311A and 312A follow the movement while remaining opposite the extraction cylinders.

The upper drying module 300B above the lower drying module 300A has an almost similar structure; it defines with the same the drying corridor CS. The upper module 300B shall preferably be slightly shorter than the lower module 300A to facilitate the arrival of the products (P) on the upper run of the conveyor 301A of the lower module 300A and their regular distribution in a layer before entering into contact with the upper module 300B.

The upper module 300B consists of a conveyor 301B with a conveyor belt 302B which has a microfibre strip layer 31 OB. The conveyor belt 302B with the layer 31 OB passes over the two deflector cylinders 303B and 304B, of which at least one (304B) is a driven cylinder fitted with a motor 305B. If required, the lower run of the conveyor belt 302B which defines the drying corridor CS with the counterpart of the belt 302A of the drying module 300A is supported from behind against the support 306B such as a sliding plate so as to maintain the regularity of the interval between the two conveyor belts 300A and 300B.

[0035] If required, the upper conveyor belt 300B may be guided and supported by a support or guide 306B for its lower run by the sides, so as to avoid the lower run forming a bump and thereby reducing the height of the drying corridor CS and pushing the products to be dried, thus risking damaging them by partial crushing.

[0036] The upper conveyor belt 302B can be thus made rigid using transversal bars of which the ends are guided by rails for which the details have not been provided.

[0037] The conveyor belt 302B passes over two deflector cylinders 303B and 304B, of which one (304B) is fitted with a motor 305B connected to the control centre 10 which ensures the adjustment of the transport speed V2 of this conveyor belt 302B.

[0038] The return run of the conveyor belt 302B passes through a moisture extractor 350B constituted by extraction cylinders 351B and 352B and to ensure this cooperation, the return run is, for example, supported by a plate or another support device 307B such that it is in an appropriate position in relation to the extraction cylinders 351B and 352B, which can have the same structure as the perforated cylinder 250 in figure 1.

[0039] The pressure cylinders 311B and 312B are connected to the extraction cylinders.

[0040] The moisture extractor 350B is fitted with an actuator 353B to control the back-and-forth movement VV of the extraction cylinders 351B and 352B, of the pressure cylinders 311B and 312B and of the treatment installation 360B for a quicker and more effective action without excluding the functioning of the device 350B which is in a fixed position in relation to the conveyor belt 301B.

[0041] The installation 1C is fitted with a height adjustment device 11 (e) of the drying corridor CS depending on the nature, structure and fragility of the products to be dried and their thickness in a randomly chosen position. This adjustment is useful for ensuring more effective drying while arranging the products to ensure the best possible contact with the microfibres without damaging or crushing the products when they pass through the drying corridor.

[0042] The travel speeds V1 and V2 of the conveyor belts 302A and 302B are set depending on the nature of the products to be dried. The installation allows an equal transport speed to be set in order to ensure that the products remain in the same position in relation to the two conveyor belts when they pass into the drying corridor. But depending on the nature of the products, it may be beneficial to ensure the functioning of the drying modules 300A and 300B at slightly different travel speeds V1 and V2, for example by circulating the belt 302B of the upper module 300B at a slightly lower speed V2 than the speed V1 of the lower module 300A so that the products driven at speed V1 of the lower belt 302A rub in a direction opposite to the upper belt V2 or are driven by it.

[0043] The reverse is also possible, i.e. a travel speed V1 for the lower belt 302A which is lower than that of the upper belt 302B so that the upper belt rubs in the opposite direction on the products and thus ensures particularly effective drying of the upper surface of the leaves.

[0044] Depending on the case, the products (P) simultaneously rub against the lower belt 302A and the upper belt 302B.

[0045] The tests carried out as part of the invention have shown that the surface moisture of the products exiting the drying installation is lower than 3%. The installations in figures 3 and 4 particularly arrange the fragile structure of the products; owing to this, there is no compression, only simple contact and little or no friction, since there is not much difference in speed. This contact is nevertheless sufficient to effectively remove the moisture from both surfaces.

[0046] According to other methods of execution, in the case of products which are particularly contorted in shape, it is possible to cascade several modules or paired modules in order to increase the effectiveness of the absorption of the surface moisture of the products.

[0047] Figure 5 shows an example of the drying installation 1D consisting of two parts 1C and 1C' which consist of a drying installation each as shown in figure 4, mounted in series to dry the products with contorted surfaces as quickly as possible, because they retain a lot of water in cavities which are difficult to access.

[0048] These two installations 1C and 1C' which form a global installation 1D can be separated by turnover equipment which is not represented in the figure and which receives the products exiting the first part 1C of the installation to transfer them in an upside down position in the second part 1C.

[0049] In accordance with a variant, the height of the installations 1C and 1C' can be adjusted in relation with one another so that, depending on the nature, dimensions and other parameters of the products, the height of the outlet of the first installation 1C can be adjusted in relation to the inlet of the second installation 1C' (or in reverse or combination), and to ensure that, depending on the trajectory of the fall, statistics have shown that the flat products arrive in an up turned position at the inlet of the lower conveyor belt of the second installation 1C.

[0050] Figure 6 shows, in a highly simplified manner, another method of execution of a drying installation 1E consisting of two parts which each consist of an installation 1C and 1C, cooperating with each other in series but positioned almost one above the other. Each of these installations corresponds with the simple installation represented more thoroughly in figure 4. The representation of each installation - 1C and 1C - is limited to the essential parts.

[0051] The products arrive on the lower conveyor of the upper installation 1C and are then transferred to the lower installation 1 C, either by the action of gravity or preferably by a guide which receives the flat products at the outlet of the first installation and guides them, if possible, towards the second installation and, owing to this transfer, turns the flat products upside down.

[0052] This upturning may also be made more effective or executed by a guide 12, formed by an arcuate surface, covering the outlet of the conveyor belt of the first part of the installation around the outlet cylinder, in order to ensure that products, such as leaves or pieces of leaves, which need to be retained in their relative position in relation to the lower conveyor arrive in an upturned position under this conveyor.

[0053] In accordance with other variants, the drying modules or installations in figures 1 and 4 may be combined.

[0054] Various similar installations are as described in particular for figure 4, fitted with a control centre 10 which controls the functioning of the drying installation in combination with the other parts of a more complete installation upstream and downstream. Another advantage is that the various installations or parts of installations also include an adjustment device which allows the interval of the drying zone, such as the height of the drying corridor, to be set depending on the nature, dimensions and fragility of the products.

[0055] This invention is applicable primarily to the drying of surface water of vegetable products such as pieces of salad leaves, in particular those from a wash bath.

NOMENCLATURE

[0056] 1, 1 A, 1B, 1C, 1D Installation for drying 10 Control station 11 Actuator for adjusting the height of the drying corridor 12 Guide 100 Support surface 200 Drying module 210 Drying surface, drying belt 211 Support surface of the belt 212 Layer of microfibre strips /microfibre strips 213 Pressure cylinder 220 Guide cylinder of the belt 221 Guide cylinder of the belt 222 Support surface 250 Moisture extractor 251 Perforated cylinder 252 Suction chamber 253 Negative pressure sector 260 Treatment installation 270 Ramp 271 Drainage mat P Product ZC Contact zone ZA Support zone ZS Drying zone CS Drying corridor e Height of the drying corridor V1, V2 Travel speed of the conveyor belts VV Alternative movement of the drying installation 100A Support surface 200A Drying module 200B Drying module 21OA Drying belt 21 OB Drying belt 212A Layer of microfibre strips/microfibre strips 212B Microfibre strips 220A Cylinder bearing the drying belt

220B Cylinder bearing the drying belt 201B 250A Moisture extractor 300A,B Drying module 301 A,B Belt conveyor 302A,B Conveyor belt 303A,B Deflector cylinder 304A,B Deflector cylinder 305A,B Motor 306A,B Support 307A,B Support 310A,B Layer of microfibre strips 311 A,B Pressure cylinder 312A,B Pressure cylinder 350A,B Moisture extractor 351 A,B Extraction cylinder 352A,B Extraction cylinder 353A,B Actuator 360A,B Treatment installation

Claims

1. Plant for drying wet vegetable products which are flat, irregular in shape and fragile and where surface moisture can be removed from the products and where the plant can be penetrated by the products to be dried, characterized in that: it comprises at least one drying module (200, 200A, 200B, 300A, 300B) which has: - a support surface (100, 100A, 306A, 306B) for receiving the products (P) to be dried, - a touch zone (ZC, CS) for the products to be dried fixed between the support surface (100) and a drying surface (210, 210A, 21 OB) provided with a microfibre fringe cloth (212, 212A, 212B) , 310A, 31 OB) in the touch zone (ZC, CS), - a device for extracting moisture (250, 250A, 350A, 350B) and located after the contact zone (ZC, CS) in the flow direction of the drying surface (210) - and this in order to compress the drying surface and make it suitable for absorbing moisture.

Installation according to claim 1, characterized in that the drying surface (210) is formed by a band provided with a cloth with fringes of microfibre (212).

Installation according to claim 1, characterized in that the support surface (100) is provided on a conveyor belt adapted to pass at the same speed as the drying belt (210) in the contact zone (ZC).

System according to claim 1, characterized in that the drying surface (210) is provided on a sleeve member supported by a cylinder (220A) driven for rotation.

Installation according to claim 1, characterized in that the unit for extracting moisture (250) is a perforated cylinder (251) which, as it rotates, is in contact with the drying surface (210) in order to be able to perform a compression in the latter. compression zone (ZA), in which level of compression zone the perforated cylinder (251) is connected to a vacuum source (252) for extraction of moisture which is extruded by the drying surface (210) and contained therein.

System according to claim 1, characterized in that it is made up of two drying modules (200A, 200B, 300A, 300B) forming a pair and each module forming a support surface for the second module, so that between these supporting surfaces the contact zone (ZC) is determined through which touch zone the products (P) to be dried can pass.

Installation according to claim 6, characterized in that each drying module (300A, 300B) is a conveyor (301A, 301B) with a conveyor belt (302A, 302B) provided with a microfiber fringe (310A, 31 OB) tab. ), and where the drying modules are mounted substantially parallel to each other and where there is a lower module (300A) and an upper module (300B) disposed above the lower module (300A) and whose tabs define the touch zone (ZC) ) designed as a channel (CS) and provided with a control device for controlling the speed of the passing conveyor belts (302A, 302B) and provided with any dew other than that passing through the drying channel (CZ) with a device for extracting moisture (250A, 250B).

System according to claim 7, characterized in that the distance between the two drying modules (300A, 300B) in the system (1C) can be adjusted in order to control the height (e) of the drying channel (CS).

System according to claim 6, characterized in that the speed of movement (V1, V2) of each of the conveyor belts (302A, 302B) is controlled by a control apparatus (10).

Plant according to claim 7, characterized in that it is constructed by a series of sub-plants, each constructed of two drying modules (300A, 300B), each formed by a conveyor with conveyor belt (302A, 302B) and provided with with a tablecloth with microfiber fringes (300A, 300B), the conveyor belts being mounted substantially parallel to each other, and having a lower module (300A) and an upper module (300B) disposed over the lower module and together with it defining a drying channel (CS) and a control means for controlling the movement speed of the belt conveyors (302A, 302B) in each drying module and a guide (12) for controlling the products from the output of a sub-plant to the entrance of the subsequent sub-plant, which systems may be mounted in series one after the other or on top of one another.

Installation according to claim 1, characterized in that the module (200) comprises a treatment device (260) for treating the dry drying surface (210) - and this at the exit of a suction zone (ZA) for extraction of moisture.