Ball dryer, suitable for drying products, in particular in the form of particles or fragments

Abstract

The present invention relates to a bead dryer (1), adapted for drying products, particularly in the form of particles or fragments. The bead dryer (1) comprises a drum (2), delimiting a drying chamber (3), and air suction means (6) for creating a negative pressure in said drying chamber (3). The drum (2) includes: - at least one discharge opening (26) comprising a lower annular slot (26), and - a lower wall (23) that is rotatable relative to said side wall (21).

Description

Technical field of the invention

[0001] The present invention relates to the technical field of ball dryers, suitable for drying products, in particular in the form of particles or fragments, in particular products made of flexible and porous material. State of the art

[0002] In the field of material processing by compaction, grinding and drying, it is common to use grinding media such as balls, iron bars, or steel balls.

[0003] Some grinding solutions involve horizontal grinding media mills, particularly those using balls or pellets.

[0004] These systems employ a grinding charge to crush material without subsequent separation, meaning that the crushed materials are often mixed with fluids from the grinding process.

[0005] This method, although common, does not allow the material to dry effectively since the extracted aqueous solution is generally reincorporated into the materials.

[0006] To improve the evacuation of the aqueous phase, some technical solutions have explored the use of central rotors to project the materials against the walls of the crusher while accelerating high-speed balls towards the material.

[0007] Although this approach has the advantage of potentially increasing grinding efficiency, it is limited by practical constraints such as high rotational speed, which can induce significant wear on the crusher components and reduce machine availability due to the frequent maintenance required.

[0008] In view of the above, there is still a need for improved drying solutions, particularly in terms of energy efficiency and reduced material wear. Presentation of the invention

[0009] In order to remedy the aforementioned drawback of the prior art, the present invention proposes a new ball dryer, suitable for drying products, in particular in the form of particles or fragments, in particular products made of flexible and porous material.

[0010] This ball dryer includes: a drum delimiting a drying chamber intended to contain said products to be dried and to contain added beads to participate in said drying, and air suction means, connected to said drying chamber, for creating a negative pressure in said drying chamber, which drum, defining a vertically oriented longitudinal axis, comprises: a cylindrical side wall arranged coaxially with respect to said longitudinal axis, an upper wall, connected to said side wall, and a lower wall, which drum further comprises: at least one supply opening, for supplying said drying chamber with said products to be dried, and at least one discharge opening, for the discharge of said products after drying, which at least one discharge opening comprises a lower annular slot (also called an "annular gap") which is delimited between: a lower edge of said side wall,opposite said lower wall, and a peripheral border of said lower wall, opposite said side wall, and which lower wall is rotatable relative to said side wall, along an axis of rotation oriented coaxially with said longitudinal axis, and cooperates with rotational operating means, so that, when said lower wall is rotated, the products to be dried are projected into the drying chamber, possibly in the direction of said upper wall, and said beads are held at the level of the lower annular slot by a centrifugal force.

[0011] Thus, the invention provides a solution for drying the material by forcing the extraction of water molecules present in the material to be treated, for example soft and porous materials, by a mechanical phenomenon of high-speed crushing using balls.

[0012] Furthermore, this solution allows for an increase in product density after processing. Indeed, the crushing and rolling of the incoming material by the beads results in a decrease in volume and therefore an increase in density. This makes it possible to reduce the volume of the residual solid fraction and / or increase the ratio of dry matter to total residual matter.

[0013] This technical solution makes it possible to further reduce the evaporation temperature and to use the incoming air as a vector for the extraction of the existing humidity.

[0014] Other non-limiting and advantageous characteristics of the product according to the invention, taken individually or in all technically possible combinations, are as follows: an upper face of the lower wall is underlying the lower edge of the side wall; and the upper face of the peripheral edge of said lower wall extends opposite the lower edge of the side wall, projecting from the inner face of the side wall, or recessed from the inner face of the side wall, towards the longitudinal axis; said lower wall has an upper face provided with at least one radial structure which, when said lower wall is rotated, is structured to participate in the projection of the products within the drying chamber, advantageously in the direction of said upper wall, and to generate the centrifugal force on said balls adapted to maintain said balls at the level of the lower annular slot;preferably, said at least one radial structure consists of a flap or a paddle, oriented radially and perpendicularly to the upper face of said lower wall, which at least one radial structure preferably has a beveled inner edge; the air intake means include at least one fan module, connected to said drying chamber via at least one outlet orifice, for example through said upper wall, optionally a damper equipping said at least one outlet orifice, means for measuring the depression in the drying chamber, and control means, for controlling said depression, via said at least one fan module (optionally frequency controllable) and / or via said damper, taking into account the values ​​collected by said measuring means;said drum includes means for supplying fresh air, for example a lower wall having at least one opening for the inlet of fresh air, or a tubular shaft, arranged coaxially with said longitudinal axis, having at least one opening for the inlet of fresh air, or the side wall having at least one opening for the inlet of fresh air, or the upper wall having at least one opening for the inlet of fresh air; which tubular shaft has at least one end opening for the inlet of fresh air, and a plurality of lateral orifices, provided in a cylindrical wall of said tubular shaft, for supplying the drying chamber with said fresh air; preferably, said at least one end opening is provided at the level of an upper end of said tubular shaft and in that the lateral orifices have diameters increasing in a direction oriented from the upper wall towards the lower wall;Preferably, the fresh air supply means consist of means for blowing heated fresh air; the drying chamber contains beads whose diameter is greater than the dimension of the lower annular slot, for example beads having a diameter ranging from 15 to 100 mm and a slot dimension greater than 0 mm up to 90 mm; preferably, the number of beads is adapted to distribute themselves over at least three levels when said lower wall is rotated; the drying chamber contains an intermediate wall, movable in rotation relative to said cylindrical side wall along an axis of rotation oriented coaxially with said longitudinal axis, which intermediate wall is located at a distance from said upper wall and said lower wall; the diameter of said intermediate wall is smaller than the diameter of the lower wall, to define an intermediate annular slot with the inner face of the side wall;The dimension of said intermediate annular slot is greater than the dimension of said lower annular slot; said intermediate wall carries second balls whose diameter is greater than the dimension of the intermediate annular slot, for example balls having a diameter ranging from 15 to 100 mm and a dimension of the intermediate annular slot ranging from 10 to 90 mm; said at least one feed opening is provided through said side wall and / or through the upper wall; the lower wall carries a central shaft equipped with at least one radial element, advantageously operated in rotation, located at a distance from said upper wall and said lower wall, for loosening the material (for example, chain or flails); it includes means for adjusting the height of the side wall and / or the lower wall, for setting the dimension of the lower annular slot.

[0015] The present invention further relates to a drying system, adapted for drying products in the form of particles, in particular products made of flexible and porous material.

[0016] The drying system comprises the following components: a heated hopper, a heated conveyor, cooperating with said at least one feed opening of said ball dryer according to the invention, said ball dryer, whose air suction means are advantageously connected with said heated hopper and / or said heated conveyor, a downstream conveyor, cooperating with said at least one discharge opening of said ball dryer.

[0017] The present invention further relates to the method for drying products, for example in the form of particles or fragments, in particular products made of flexible and porous material, by the use of a ball dryer according to the invention.

[0018] The drying process includes an operation of rotating said lower wall, for example at a speed of 500 to 1,500 rpm in steady state.

[0019] Preferably, the air intake means generate an airflow towards at least one outlet orifice.

[0020] The airflow is adjusted to ensure that the drying chamber is kept under negative pressure, to allow for air renewal, to remove moisture and vapors extracted from the products to be dried, while preventing the products from being drawn towards at least one outlet.

[0021] Of course, the different features, variants and embodiments of the invention can be combined with each other in various ways as long as they are not incompatible or mutually exclusive. Detailed description of the invention

[0022] Furthermore, various other features of the invention become apparent from the attached description made with reference to the drawings which illustrate non-limiting embodiments of the invention and where: [ Fig. 1 ] is a general and schematic view of a drying system according to the invention; [ Fig. 2 ] is a cross-sectional and schematic view of a ball dryer according to the invention; [ Fig. 3 ] is a schematic and partial view of the ball dryer according to the invention, illustrating in more detail the lower annular slot and a "theoretical" arrangement of the balls when the lower wall is rotated; [ Fig. 4 ] is yet another schematic and partial view of the ball dryer according to the invention, illustrating in further detail the lower annular slot and a ball during the rotation of the lower wall; [ Fig. 5 ] is a schematic and perspective view of the lower wall; [ Fig. 6] is a schematic and partial view of one embodiment of the central shaft equipped with at least one removable radial component; [ Fig. 7 ] is a cross-sectional and schematic view of another ball dryer according to the invention, according to an embodiment comprising an intermediate wall.

[0023] It should be noted that, in these figures, the structural and / or functional elements common to the different variants may have the same references.

[0024] The present invention thus relates to a ball dryer 1, adapted for drying products, in particular in the form of particles or fragments, in particular products made of flexible and porous material.

[0025] By "suitable for drying products", we advantageously mean a solution designed to reduce the water content (or even any other liquid) of products (also called "material") in an efficient and controlled manner.

[0026] The solution according to the invention is thus advantageously designed to efficiently reduce the moisture content of products, in particular organic matter and waste, by using a process combining high-speed mechanical crushing by balls in combination with an air vacuum (to facilitate the extraction of water), possibly preceded by a preheating phase of the material, thus optimizing evaporation at a reduced temperature and using the incoming air as a vector for the extraction of moisture.

[0027] By "particle or fragment form" we advantageously mean products or materials that have been reduced to small sizes or distinct pieces.

[0028] As further developed, this reduction into particles or fragments is advantageously achieved through mechanical processes such as grinding, crushing, or cutting, thus facilitating subsequent treatments like drying. In the context of drying, the reduction into particles or fragments increases the exposed surface area of ​​the material, allowing for faster and more efficient evaporation of moisture.

[0029] The term "products made of flexible and porous material" advantageously refers to objects or substances made from materials that possess both flexibility and a structure allowing the passage of air or fluids. These materials, due to their porosity, contain numerous voids or interstices that can capture, retain, or release fluids, including gases or liquids.

[0030] Preferably, but not limited to, "product" means a material with a carbon base (materials from living organisms, plastics, organic waste, green waste, municipal waste, organic fraction of household waste).

[0031] In general, the ball dryer 1 according to the invention, illustrated in particular on the figures 2 to 4 , understand : a drum 2 delimiting a drying chamber 3 intended to contain the products to be dried (not shown) and to contain beads 5 brought in to participate in said drying, and air suction means 6, connected to the drying chamber 3, for putting this drying chamber 3 into negative pressure. Was

[0032] In general, the shaft 2 defines a longitudinal axis 2', oriented vertically.

[0033] This drum 2 comprises a combination of walls that delimit the drying chamber 3: a side wall 21, cylindrical and arranged coaxially with respect to said longitudinal axis 2', a top wall 22, connected to the side wall 21, and a bottom wall 23.

[0034] The side wall 21 advantageously has a circular section, constant over its height.

[0035] This side wall 21 advantageously has two borders: an upper border 211, advantageously connected to the upper wall 22, and a lower border 212, advantageously adjacent to the lower wall 23, described in more detail later.

[0036] The lower border 212 extends advantageously in a plane perpendicular to the longitudinal axis 2'.

[0037] This side wall 21 advantageously includes an inner face 213, laterally delimiting the drying chamber 3.

[0038] The lateral wall 21 extends advantageously between the upper wall 22 and the lower wall 23.

[0039] The upper wall 22 and / or the lower wall 23 advantageously extends perpendicularly to the longitudinal axis 2'.

[0040] The lower wall 23, for example in the form of a disk or a plate, includes in particular: a peripheral border 231, extending along (also called "adjacent") the lower border 212 of the side wall 21, and an upper face 232, delimiting the lower end of the drying chamber 3, serving as a support surface for the products to be dried and for the beads 5.

[0041] The peripheral border 231, advantageously circular, advantageously defines the diameter of this lower wall 23.

[0042] Preferably, the upper face 232 of this lower wall 23 is flat, oriented perpendicularly to the longitudinal axis 2'.

[0043] For example, barrel 2 has the following general dimensions: a height (defined between the upper wall 22 and the lower wall 23) ranging from 500 mm to 3 times the diameter (defined by the side wall 21), a diameter (defined by the side wall 21) ranging from 200 mm to 2,500 mm.

[0044] For the flow of products through drying chamber 3, drum 2 still has at least two openings: at least one supply opening 25, for supplying the drying chamber 3 with the products to be dried, and at least one discharge opening 26, for discharging the products after drying.

[0045] In this case, the barrel 2 advantageously includes a feed opening 25 which is provided through the side wall 21, preferably in an area located away from the lower wall 23, for example halfway up the side wall 21.

[0046] Alternatively or in addition, said at least one supply opening 25 may be provided through the upper wall 22.

[0047] Furthermore, the aforementioned at least one evacuation opening 26 is visible in particular on the figures 3 and 4 .

[0048] According to the invention, the drainage opening 26 comprises (or "consists of") a lower annular slot 26 (also called the "annular gap") which is delimited between: a lower border 212 of said side wall 21, opposite said lower wall 23, and a peripheral border 231 of the lower wall 23, opposite side wall 21.

[0049] The lower annular slot 26 thus advantageously provides a passage to the outside, from the drying chamber 3, for the products that have undergone the drying process. This configuration ensures a smooth and continuous transition of the products through the drying chamber 3.

[0050] This lower annular slot 26 can advantageously take on various configurations, particularly for effective balancing: the prevention, or at least keeping below a maximum threshold, of the heating of the products when they pass through the lower annular slot 26, and the maintenance of a flow of products which guarantees a sufficient residence time in the drying chamber 3 for optimal treatment.

[0051] According to a preferred embodiment, the upper face 232 of the lower wall 23 is underlying the lower border 212 of the side wall 21.

[0052] In other words, the upper face 232 of the lower wall 23 lies below a plane (perpendicular to the longitudinal axis 2') defined by the lower border 212 of the lateral wall 21.

[0053] And the upper face 231a of the peripheral border 231 of the lower wall 23 extends opposite the lower border 212 of the side wall 21, projecting from the inner face 213 of the side wall 21 ( figures 3 and 4 ).

[0054] The diameter of the lower wall 23 is thus advantageously greater than the diameter defined by the inner face 213 of the lateral wall 21.

[0055] Alternatively, the upper face 231a of the peripheral border 231 of the lower wall 23 extends inward from the inner face 213 of the lateral wall 21, towards the longitudinal axis 2' (not shown).

[0056] The diameter of the lower wall 23 is thus advantageously equal to, or less than, the diameter defined by the inner face 213 of the lateral wall 21.

[0057] Generally, the dimension of the lower annular slot 26 is greater than 0 mm, up to 90 mm. Preferably, this dimension of the lower annular slot 26 is from 2 mm to 15 mm.

[0058] By "lower annular slot dimension 26", advantageously means the smallest distance measured in a radial plane passing through the longitudinal axis 2', between the lower edge 212 of said lateral wall 21 and the peripheral edge 231 of the lower wall 23.

[0059] This dimension of the lower annular slot 26 further defines the passage for the product when it exits the drying chamber 3.

[0060] Preferably, the upper face 231a of the peripheral border 231 of the lower wall 23 has a chamfer 231b.

[0061] This feature is particularly useful for limiting friction with respect to the products between the side wall 21 and the lower wall 23, when passing through the lower annular slot 26.

[0062] According to yet another particular embodiment, not shown, the ball dryer 1 includes means for maneuvering the side wall 21 and / or the lower wall 23 in height, for adjusting the dimension of the lower annular slot 26.

[0063] These means of operation consist for example of a motor which, by means of a worm screw, drives the lateral wall 21 in translation relative to the lower wall 23 (or vice versa).

[0064] This setting then helps to regulate the outgoing material flow, influencing the residence time for the material inside the drying chamber 3.

[0065] And according to the invention, the lower wall 23 is mobile in rotation relative to said lateral wall 21, along an axis of rotation oriented coaxially with said longitudinal axis 2'.

[0066] Rotating the lower wall 23 advantageously generates two phenomena, which are further described below: The products to be dried are projected into the drying chamber 3, possibly towards the upper wall 22, participating in the mixing and drying, and the balls 5 are held at the level of the lower annular slot 26 by a centrifugal force, forcing the products to cross this dynamic interface to exit the drying chamber 3.

[0067] In other words, when the lower wall 23 is rotated, the balls 5 tend to group together in an angle of the drying chamber 3, said angle being defined by the side wall 21 and by the lower wall 23.

[0068] For this purpose, the lower wall 23 also cooperates with rotating maneuvering means 7.

[0069] For example, these means of rotational maneuvering 7 include a driving element, such as an electric motor, cooperating with the inner wall 23 through a drive element, such as a belt, a mechanical transmission shaft or a chain.

[0070] To participate in the movements of the products and the balls 5 in the drying chamber 3, the upper face 232 of the lower wall 23 advantageously comprises at least one radial structure 235.

[0071] During the rotation of the lower wall 23, said at least one radial structure 235 is advantageously structured to participate: to the projection and mixing of the products within the drying chamber 3, advantageously in the direction of said upper wall 22, and to generate the centrifugal force on the balls 5 adapted to maintain the balls 5 at the level of the lower annular slot 26.

[0072] According to one embodiment, said at least one radial structure 235 consists of a flap or a pallet, oriented radially and perpendicularly to the upper face 232 of the lower wall 23.

[0073] Said at least one radial structure 235, for example parallelepiped, advantageously comprises: an inner edge 235a, on the side of the longitudinal axis 2', an outer edge 235b, opposite the lateral wall 21, a longitudinal edge 235c, free, at a distance from the lower wall 23, and two lateral faces 235d.

[0074] Preferably, the inner edge 235a is beveled, with a slope or inclined plane, gradually moving away from the longitudinal axis 2' from the lower wall 23.

[0075] This feature has the function of lifting the material in order to increase the vertical projection and mixing of the material.

[0076] The outer edge 235b advantageously extends parallel to the longitudinal axis 2'. The outer edge 235b advantageously extends at a distance from the lateral wall 21 of the shaft 2.

[0077] The longitudinal edge 235c is advantageously perpendicular to the longitudinal axis 2'.

[0078] The lateral faces 235d are advantageously parallel to each other and to the longitudinal axis.

[0079] This radial structure 235 can also consist of a spherical cap (for example a hemisphere) or a cone.

[0080] As illustrated on the figure 5, the lower wall 23 advantageously comprises several radial structures 235 which are regularly distributed over the circumference of the longitudinal axis 2'.

[0081] For example, the lower wall 23 comprises: a group of external radial structures 235, in an external ring of this lower wall 23, and a group of internal radial structures 235, in an internal ring of this lower wall 23.

[0082] The radial structures 235 of these two groups are angularly offset.

[0083] For example, a radial structure 235 has a dimension in length which is less than a quarter of the diameter of the lower wall 23.

[0084] According to one embodiment, a tubular shaft 281 is fixed to the lower wall 23, arranged coaxially with the longitudinal axis 2'. It is thus also mobile in rotation relative to the lateral wall 21, about an axis of rotation oriented coaxially with said longitudinal axis 2'.

[0085] In this case, the tubular shaft 281 advantageously extends beyond the upper wall 22 and the lower wall 23, defining three sections: an upper section 281a, opening above the upper wall 22, forming its upper end 281a, a central section 281b, extending over the height of the drying chamber 3, and a lower section 281c, opening below the lower wall 23, forming its lower end 281c.

[0086] The tubular shaft 281 cooperates here with the rotating maneuvering means 7, in this case via the upper section 281a. The rotation of the lower wall 23 is ensured here by means of the tubular shaft 281.

[0087] Alternatively, as depicted on the figure 7 The tubular shaft 281 can be replaced by a solid shaft 281 (designated by the same reference number for simplicity). Generally, both the tubular shaft and the solid shaft can still be referred to as the "central shaft".

[0088] In general terms, the central shaft 281 can be equipped with at least one radial member 285, advantageously operated in rotation around the longitudinal axis 21', located at a distance from the upper wall 22 and the lower wall 23, to loosen the material (for example chain or flails).

[0089] This arrangement is designed to loosen the material and promote its separation and mixing during the drying process. The radial element 285, rotating with the central shaft 281, dynamically impacts the products in the drying chamber 3, thus helping to break up the agglomerates of material and increasing the contact surface area of ​​the material in order to help release trapped moisture.

[0090] A particular form of radial organ 285 is schematically illustrated on the figure 6 .

[0091] This radial organ 285 consists here of a removable flail, secured to the central shaft 281 by means of removable fastening means 286, for example a male / female couple locked by a removable pin.

[0092] This configuration allows for easy assembly and disassembly for maintenance or replacement. This modular design ensures that the radial component 285 can be adjusted or replaced according to the specific characteristics of the material being processed or the wear and tear on the equipment.

[0093] Furthermore, in general, the air extraction means 6, connected to the drying chamber 3, advantageously ensure the depressurization of this drying chamber 3.

[0094] The term "depression" refers specifically to the state in which the air pressure inside the drying chamber 3 is maintained below the ambient atmospheric pressure. This condition is created and regulated by means of the suction devices 6, which extract air from the drying chamber 3 to reduce its internal pressure and to facilitate the extraction of vapors and ensure the renewal of fresh air.

[0095] Without being limited by any theory, the drop in internal pressure not only ensures faster evaporation, but also the intake of fresh air towards drying chamber 3. This introduction of fresh air helps to dilute and reduce the residual humidity in the air of drying chamber 3. Indeed, by renewing the indoor air with air less saturated with humidity, the evaporation process is facilitated and more efficient.

[0096] Fresh air entering drying chamber 3 helps maintain a less humid environment, contributing to optimal water extraction from the products being dried. This dynamic helps to more effectively remove the extracted moisture, preventing ambient air saturation and enabling a continuous and efficient drying cycle. Therefore, the combination of negative pressure and air renewal maximizes the performance of the drying process, optimizing water extraction while minimizing energy consumption and the time required to reach the desired level of dryness.

[0097] According to a preferred embodiment, described in connection with the figure 2 Air extraction means 6 advantageously include: at least one fan module 61, connected to the drying chamber 3 via at least one outlet port 27, optionally a valve 62 equipping said at least one outlet port 27, means for measuring 63 the depression in the drying chamber 3, and control means 64, for controlling said depression, taking into account the values ​​collected by said measuring means 63.

[0098] Said at least one fan module 61 is advantageously suited to create a controlled airflow through the drying chamber 3.

[0099] Connected to the drying chamber 3 via at least one outlet 27, advantageously located in the upper wall 22, the fan module 61, which may be frequency-controlled (for example, an electric fan with a speed controller), promotes the circulation and extraction of humid air and vapors. This allows for the regulation of negative pressure and ensures the renewal of fresh air inside the drying chamber 3, for efficient drying of the products.

[0100] The damper 62, installed on the outlet 27, regulates the airflow exiting the drying chamber 3. This damper 62 can be adjusted (manually or automatically via a PLC) to control the amount of air exhausted, thus optimizing the balance between the negative pressure and the velocity of the outgoing airflow. This is particularly useful for maintaining negative pressure in the drying chamber 3 without drawing material through the outlet 27.

[0101] The measuring devices 63 advantageously monitor the air pressure inside the drying chamber 3. They collect data on the negative pressure value, ensuring that the drying conditions remain within the defined parameters. Adequate negative pressure ensures that humid air is effectively extracted, promoting rapid and uniform drying of the products.

[0102] The control means 64, for example in the form of a programmable logic controller (PLC), interact advantageously with the fan module 61, which may be frequency-controlled, and / or the damper 62, adjusting their operation according to the values ​​measured by the measuring means 63. Automated control allows for real-time adjustment of the operational parameters, adapting the airflow and pressure inside the drying chamber 3 to optimize drying conditions. This integration ensures precise regulation of the drying environment, contributing to energy efficiency and the quality of the finished product.

[0103] Furthermore, in general, barrel 2 advantageously includes means of supplying fresh air 28.

[0104] These means of supplying fresh air 28 can take various forms, for example: the lower wall 23 has at least one opening for the inlet of fresh air (shape not shown), or the tubular shaft 281 has at least one opening, arranged coaxially with the longitudinal axis 2', for the inlet of fresh air, or the side wall 21 has at least one opening for the inlet of fresh air (shape not shown), or the upper wall 22 has at least one opening for the inlet of fresh air (shape not shown).

[0105] The tubular shaft 281 has a cylindrical wall 281e.

[0106] And, this tubular shaft 281 advantageously includes: at least one end opening 282, for the inlet of fresh air, and a plurality of lateral orifices 283, through, provided in the cylindrical wall 281e of the tubular shaft 281 (advantageously within the central section 281c), for supplying the drying chamber 3 with said fresh air.

[0107] The fresh air flow is thus intended to enter within said at least one end opening 282, to travel along the tubular shaft 281, and then to exit through the lateral orifices 283.

[0108] According to a preferred embodiment, said at least one end opening 282 is provided here at an upper end 281a of the tubular shaft 281.

[0109] And, as schematically illustrated on the figure 2 , the lateral orifices 283 advantageously have increasing diameters in a direction oriented from the upper wall 22 towards the lower wall 23.

[0110] This gradual increase in the diameter of the lateral openings 283, towards the lower wall 23, ensures that fresh (less humid) air is efficiently distributed throughout the entire height of the drying chamber, but with a higher flow rate on the side of the lower wall 23 where the drying requirement is most critical. This contributes to the fact that the fresh, dry air comes into direct contact with the moist products, thus facilitating rapid moisture removal and improving the overall efficiency of the drying process.

[0111] In general, the means of supplying fresh air 28 may consist of means of blowing in fresh heated air.

[0112] The means for supplying fresh heated air are configured to supply heated air (advantageously pulsed, i.e. mechanically propelled), at a determined temperature and at a determined flow rate, advantageously in such a way as to improve the drying performance of the products located inside said ball dryer 1.

[0113] In other words, the heated air, whose critical parameters include temperature and flow rate, induces a variation in the air temperature inside the ball dryer 1. This thermal variation has an impact on drying performance.

[0114] For example, the parameters of the heated air are: a temperature ranging from 100°C to 350°C, and a flow rate ranging from 100 m3 / h to 800 m3 / h. Marbles

[0115] The drying chamber 3 therefore contains balls 5, advantageously made of steel or ceramic, supported by the lower wall 23.

[0116] The diameter of these balls 5 is advantageously greater than the dimension of the lower annular slot 26.

[0117] For example, the 5 balls have a diameter ranging from 15 to 100 mm, preferably ranging from 20 mm to 30 mm.

[0118] Preferably, as shown on the figure 3 , the balls 5 are in a suitable number to be distributed over at least three levels when the said lower wall 23 is rotated.

[0119] By "stage", we advantageously mean at least one ball extending in a plane, on the one hand, perpendicular to the bisector between the lower wall 23 and the lateral wall 21 on the inner side of the drying chamber 3 and, on the other hand, at 45° with respect to the longitudinal axis 2'.

[0120] This multi-layered arrangement is primarily due to the centrifugal force generated by the rotation of the lower wall 23. When this wall begins to rotate, the beads 5, due to their mass and the centrifugal force, are projected outwards against the side wall 21 and naturally organize themselves into different layers or tiers according to their size, density, and rotational speed. This tiered configuration optimizes the interaction between the beads 5 and the product to be dried, thus maximizing the efficiency of the grinding or mixing required for the drying process.

[0121] And, due to the centrifugal force which is a function of the rotation speed of the lower wall 23, said force pushes the balls 5 outwards and distributes them more densely in the upper layers near the side wall 21 and above the lower annular slot 26, thus increasing the contact pressure of the balls 5 on the side wall 21 and the lower wall 23. As a result, this increase in pressure linked to the centrifugal force, and therefore to the rotation speed of the lower wall 23, ensures a more intense and prolonged contact between the balls 5, the side wall 21 and the lower wall 23 and the products to be processed, thus facilitating their crushing and the extraction of moisture.

[0122] These balls 5 are also advantageously in suitable numbers to be distributed over the entire circumference of the lower annular slot 26, and this over several stages when the lower wall 23 is rotated.

[0123] This distribution ensures complete coverage of the passage area, thus allowing constant and uniform contact of the balls 5 with the product as it passes through.

[0124] When the lower wall 23 rotates, the centrifugal force helps to disperse the beads 5 evenly along the lower annular slot 26, over several layers. This homogeneous, layered distribution ensures that all the products undergo increasing mechanical processing intensity until the material is expelled through the lower annular slot 26. By being distributed around the entire circumference of the lower annular slot 26 and over several layers, the beads 5 form a dynamic mechanical barrier that continuously works the product, crushing particles, improving water extraction, and facilitating the passage of dry materials out of the drying chamber 3. Drying chamber with intermediate wall

[0125] According to an alternative embodiment illustrated on the figure 7 , the drying chamber 3 can still contain an intermediate wall 29, movable in rotation relative to the lateral wall 21, along an axis of rotation oriented coaxially to the longitudinal axis 2'.

[0126] This intermediate wall 29 is advantageously supported by the central shaft 281.

[0127] The intermediate wall 29 is located at a distance from the upper wall 22 and the lower wall 23, advantageously below said at least one supply opening 25.

[0128] The diameter of this intermediate wall 29 (advantageously defined by a circular contour) is smaller than the diameter of the inner face 213 of the lateral wall 21, to define an intermediate annular slot 291 with this inner face 213 of the lateral wall 21.

[0129] And the dimension of the intermediate annular cleft 291 is advantageously greater than the dimension of the lower annular cleft 26.

[0130] Still in this embodiment variant, the intermediate wall 29 advantageously carries second balls 8 whose diameter is greater than the dimension of the intermediate annular slot 291.

[0131] For example, the second balls 8 have a diameter ranging from 15 to 100 mm and the dimension of the intermediate annular slot 291 is from 10 to 90 mm.

[0132] By "dimension of the intermediate annular slot 291", we advantageously mean the smallest distance measured in a radial plane passing through the longitudinal axis 2', between the edge of the intermediate wall 29 and the inner face 213 of the lateral wall 21. Drying system

[0133] For its implementation, the ball dryer 1 according to the invention is advantageously integrated into a drying system 10 illustrated for example on the figure 1 .

[0134] The drying system 10 comprises successively: a heated hopper 11, a heated conveyor 12, cooperating with said at least one feed opening 25 of the ball dryer 1, the ball dryer 1 according to the invention, a downstream conveyor 13, cooperating with said at least one discharge opening 26 of said ball dryer 1, for conveying the dried products.

[0135] If necessary, preferably, the heated hopper 11, equipped with a load cell and a level sensor, receives the material from the upstream line. This allows for knowledge of the density of the incoming material.

[0136] The heated hopper 11 feeds the heated conveyor 12, for example a screw conveyor, allowing the loading of the ball dryer 1.

[0137] The screw conveyor is advantageously equipped with a double wall containing a heat transfer fluid in order to heat the material inside the screw.

[0138] Preferably, this same heated conveyor 12 is advantageously equipped with a humidity sensor to determine the moisture content of the incoming product. Thus, before entering the ball dryer 1, the material is heated, its density and moisture content are known. These values ​​can be used as input data for controlling and regulating the ball dryer 1.

[0139] Preferably, the drying system 10 also includes a second moisture sensor to collect the moisture content of the material being processed, after it has passed through the bead dryer.

[0140] Preferably, the heat extracted from the ball dryer 1 is used for preheating the incoming materials, via the air suction means 6.

[0141] Preferably, the air suction means 6 are connected with the heated conveyor 12 and / or the heated hopper 11.

[0142] Hot stale air extracted from the ball dryer 1 and sent into the heated conveyor 12 and the heated hopper 11, in order to recover the energy present in the extracted air and to preheat the incoming materials in order to optimize energy. Drying process

[0143] The present invention further relates to the method for drying products, for example in the form of particles or fragments, in particular products made of flexible and porous material, by the use of a ball dryer 1 according to the invention.

[0144] Preferably, the material is pre-crushed, screened and a separation of ferrous and non-ferrous metals has been carried out upstream of the drying system 10.

[0145] The heated material is discharged by the heated conveyor 12 into the ball dryer 1.

[0146] The material falls inside the drying chamber 3, possibly until it reaches the rotating lower wall 23, causing the material to become suspended inside the drying chamber 3.

[0147] The dimension of the lower annular slot 26 is advantageously controlled with the height-adjustable means of the side wall 21 and / or the lower wall 23. This adjustment regulates the material flow, influencing the residence time inside the drying chamber 3, for the material to be treated.

[0148] During the implementation of the ball dryer 1 according to the invention, this drying process advantageously includes an operation of rotating the lower wall 23, for example at a speed ranging from 500 to 1,500 rpm in steady state.

[0149] During this rotation, the balls 5, in addition to being held in place by centrifugal force, are also set in motion due to the rotation of the lower wall 23 relative to the lateral wall 21. This relative rotation drives the balls 5 into a continuous general circular trajectory, thus improving their interaction with the product being processed.

[0150] As they move along the lower annular slot 26, the balls 5 form a dynamic moving interface where the product is not only crushed but also constantly stirred and kneaded, further facilitating the extraction and evacuation of liquids.

[0151] The balls 5 contribute to crushing the particles and material present during the suspension process. The balls 5 act as a grinding media and allow thermal energy (heat) to be transferred to the core of the circulating material. The balls 5 also contribute, through their rolling motion, to crushing the material before it exits, thus increasing its density and removing any aqueous substances present within it.

[0152] If necessary, a similar phenomenon is obtained at the intermediate annular cleft 291 in the presence of an intermediate wall 29.

[0153] Furthermore, the air suction means 6 advantageously generate an airflow towards at least one outlet orifice 27.

[0154] In practice, the airflow is advantageously adjusted to ensure that the drying chamber 3 is kept under negative pressure, allowing for air renewal, the removal of moisture and vapors extracted from the products to be dried.

[0155] At the same time, this airflow is advantageously adjusted to avoid carrying the products towards said at least one outlet orifice 27.

[0156] The airflow thus contributes to the extraction of ambient humidity inside the drying chamber 3, contributing to the drying of the material.

[0157] In general and advantageously, the control means 64 compare the moisture values, at the inlet and outlet, in order to adjust the settings of the ball dryer 1 (cycle time, value of the lower annular slot dimension 26, rotation speed of the lower wall 23, air flow speed, rotation speed of the heated conveyor 12 in order to adjust the flow rate of incoming material).

[0158] In general, the drying process according to the invention has the significant advantage of being able to be implemented continuously, with a constant supply of products which will be progressively processed and expelled through the lower annular slot 26.

[0159] This ability to operate continuously is advantageous for industries requiring high production rates and efficient processing time management. The continuous flow of material in the bead dryer 1 ensures that as soon as the products enter the drying chamber 3, they immediately begin their drying process and are progressively conveyed to the outlet without interruption. This optimizes not only energy use but also the consistency of the finished product quality, as each particle or fragment receives uniform treatment during its passage through the bead dryer 1.

[0160] The design of the ball dryer 1 further facilitates the evacuation of dried products thanks to the centrifugal force generated by the rotation of the lower wall 23, which helps to push the products towards the lower annular slot 26, thus ensuring their continuous and regular exit.

[0161] Of course, various other modifications can be made to the invention within the scope of the attached claims.

Claims

1. A bead dryer (1), adapted for drying products, particularly in the form of particles or fragments, particularly products made of flexible and porous materials, which bead dryer (1) comprises: - a drum (2) delimiting a drying chamber (3) intended to contain said products to be dried and to contain beads (5) added to participate in said drying, and - air suction means (6), connected to said drying chamber (3), for creating a negative pressure in said drying chamber (3), which drum (2), defining a vertically oriented longitudinal axis (2'), comprises: - a cylindrical side wall (21) arranged coaxially with respect to said longitudinal axis (2'), - an upper wall (22), connected to said side wall (21), and - a lower wall (23), which drum (2) further comprises: - at least one feed opening (25), for supplying said drying chamber (3) with said products to be dried,and - at least one discharge opening (26) for the discharge of said products after drying, which at least one discharge opening (26) comprises a lower annular slot (26) delimited between: - a lower edge (212) of said side wall (21), opposite said lower wall (23), and - a peripheral edge (231) of said lower wall (23), opposite said side wall (21), and which lower wall (23) is rotatable relative to said side wall (21), along an axis of rotation oriented coaxially with said longitudinal axis (2'), and cooperates with rotating operating means (7), so that, when said lower wall (23) is rotated, the products to be dried are projected into the drying chamber (3) and said beads (5) are held at the level of the lower annular slot (26) by a centrifugal force.

2. Ball dryer (1) according to claim 1, characterized in thatan upper face (232) of the lower wall (23) is underlying the lower border (212) of the lateral wall (21), and in that the upper face (231a) of the peripheral border (231) of said lower wall (23) extends: - opposite the lower border (212) of the lateral wall (21), projecting from the inner face (213) of the lateral wall (21), or - recessed from the inner face (213) of the lateral wall (21), towards the longitudinal axis (2').

3. Ball dryer (1) according to any one of claims 1 or 2, characterized in thatsaid lower wall (23) has an upper face (232) provided with at least one radial structure (235) which, when said lower wall (23) is rotated, is structured to participate in the projection of the products within the drying chamber (3), and to generate the centrifugal force on said balls (5) adapted to maintain said balls (5) at the level of the lower annular slot (26).

4. Ball dryer (1) according to claim 3, characterized in that said at least one radial structure (235) consists of a flap or a pallet, oriented radially and perpendicular to the upper face (232) of said lower wall (23).

5. Ball dryer (1) according to any one of claims 1 to 4, characterized in thatThe air intake means (6) comprise: - at least one fan module (61), connected to said drying chamber (3) via at least one outlet orifice (27), for example through said upper wall (22), - optionally a valve (62) equipping said at least one outlet orifice (27), - means for measuring the depression in the drying chamber, and - means for controlling said depression, via said at least one fan module (61) optionally controllable by frequency and / or via said valve (62), taking into account the values ​​collected by said measuring means (63).

6. Ball dryer (1) according to any one of claims 1 to 5, characterized in thatsaid drum (2) includes fresh air supply means (28), preferably fresh air supply means (28) consisting of heated fresh air blowing means, which fresh air supply means (28) advantageously include at least one opening, for the entry of fresh air, provided in: - the lower wall (23), - the tubular shaft (281), arranged coaxially with the longitudinal axis (2'), - the side wall (21), - the upper wall (22).

7. Ball dryer (1) according to claim 6, characterized in thatThe means for supplying fresh air (28) comprise a tubular shaft (281), arranged coaxially with said longitudinal axis, which tubular shaft (281) preferably has at least one end opening (282) for the inlet of fresh air, and a plurality of lateral orifices (283) provided in a cylindrical wall (281e) of said tubular shaft (281) for supplying the drying chamber (3) with said fresh air, preferably said at least one end opening (282) is provided at an upper end (281a) of said tubular shaft (281) and in that the lateral orifices (283) have increasing diameters in a direction oriented from the upper wall (22) towards the lower wall (23).

8. Ball dryer (1), according to any one of claims 1 to 7, characterized in thatthe drying chamber (3) contains beads (5) whose diameter is greater than the dimension of the lower annular slot (26), for example beads (5) having a diameter ranging from 15 to 100 mm and a dimension of the lower annular slot (26) which is greater than 0 mm, up to 90 mm.

9. Ball dryer (1), according to any one of claims 1 to 8, characterized in that the drying chamber (3) contains an intermediate wall (29), movable in rotation relative to said cylindrical side wall (21) along an axis of rotation oriented coaxially with said longitudinal axis (2'), which intermediate wall (29) is located at a distance from said upper wall (22) and said lower wall (23), in that the diameter of said intermediate wall (29) is smaller compared to the diameter of the inner face (213) of the lateral wall (21), to define an intermediate annular slot (291) with the inner face (213) of the lateral wall (21), in thatthe dimension of said intermediate annular slot (291) is greater than the dimension of said lower annular slot (26), and in that said intermediate wall (29) carries second balls (8) whose diameter is greater than the dimension of the intermediate annular slot (291).

10. Ball dryer (1), according to any one of claims 1 to 9, characterized in that said at least one supply opening (25) is provided through said side wall (21) and / or said top wall (22).

11. Ball dryer (1), according to any one of claims 1 to 10, characterized in that the lower wall (23) carries a central shaft (281) equipped with at least one radial member (285), located at a distance from said upper wall (22) and said lower wall (23), for loosening the material.

12. Ball dryer (1), according to any one of claims 1 to 11, characterized in thatIt includes means for maneuvering the side wall (21) and / or the bottom wall (23) in height, for adjusting the height of the lower annular slot (26).

13. Drying system (10), adapted for drying products in the form of particles, in particular products made of flexible and porous material, which drying system (10) comprises successively: - a heated hopper (11), - a heated conveyor (12), cooperating with said at least one feed opening (25) of said ball dryer (1) according to any one of claims 1 to 13, - said ball dryer (1) according to any one of claims 1 to 12, the air suction means (6) of which are advantageously connected with said heated hopper (11) and / or said heated conveyor (12), - a downstream conveyor (13), cooperating with said at least one discharge opening (26) of said ball dryer (1) according to any one of claims 1 to 12.

14. Method for drying products, for example in the form of particles or fragments, in particular products made of soft and porous material, by implementing a ball dryer (1) according to any one of claims 1 to 12, which drying method comprises an operation of rotating said lower wall (23), for example at a speed of 500 to 1,500 rpm in steady state.

15. A method for drying products according to claim 14, characterized in that the air suction means (6) generate an airflow towards at least one outlet orifice (27), said airflow being adjusted to ensure maintenance under negative pressure of said drying chamber (3), to allow air renewal, to remove moisture and vapors extracted from the products to be dried, while avoiding the entrainment of said products towards said at least one outlet orifice (27).

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