SYSTEM FOR THE PROCESSING OF A MATERIAL

DESCRIPTION

Technical field of the invention The present invention relates to a system for the processing of a material, in particular for the continuous mechanical and thermal processing of a material.

Background

The need for processing different types of materials and products with hot or cold fluids (vapour, air, gases of various type) is known with the purpose of triggering chemical-physical reactions useful to transform such materials and products, for example for sterilizing or making them inert.

A common processing of this type is steam sterilization, often used to break down microorganisms and other pathogens from materials and products which have to be decontaminated such as, for example, used diapers, expired medicines and other potentially pathogen objects.

This type of sterilization provides the insertion of steam, preferably saturated steam, in a closed environment wherein the material to be sterilized is inserted so as to reach temperature and pressure conditions so as to break down microorganisms and pathogen agents.

A first type of known sterilization systems, allowing steam sterilization, provides the use of autoclaves. The autoclave systems are the most commonly used, and they consist of containers inside of which the product to be sterilized is inserted. Such systems provide a “discontinuous” operation, that is with phases which are cyclically alternated to allow sterilization of predefined amounts of material.

A first phase relates to the loading in the autoclave of the material to be sterilized. Once ended the product loading phase, one proceeds with heating the system and starting the sterilization process which provides the insertion of steam at determined pressure and temperature conditions; the latter phase lasts long enough so that the death of the specific microorganism to be eliminated from the product takes place.

The phase of interrupting the thermal process and restoring the conditions which make possible to re-open safely the container follows, then to proceed with emptying the autoclave to extract the sterilized product.

The main drawbacks of this first type of systems are briefly described in the points reported hereinafter.

• Impossibility of working continuously: this first type of known systems works discontinuously, that is there are loading phases, starting of the thermal process, regulation of the thermal process, progressive stop of the thermal process and discharge of the product to be processed, which do not allow the continuous supply of the product itself;

• Frequent opening/closing of the opening/closing devices: by working discontinuously, the known systems require closing the door(s) at the beginning of the cycle, once inserted the product and re-opening the same, once concluded the cycle, to allow the discharge of the processed products. Upon frequently occurring these procedures, it happens that:

- the sealings lose their own effectiveness;

- a not perfect cleaning of the coupling and sealing elements involves the ineffectiveness of the sealings themselves;

- after a certain number of cycles, the mechanical portions subjected to fatigue, could involve the loss of centering of the opening/closing systems themselves.

• Low effectiveness of heat exchange: the known systems provide the insertion from one single point (or however with single mode) of the steam required to sterilization (and the same is valid for other possible attempts of continuous autoclaves). Since the latter has a determined pressure value, higher than the atmospheric value, once closed the door it could expand until filling up the space inside the container casing of autoclave. Should the autoclave be static, then almost certainly the steam will not succeed in coming in contact with all portions of the product, above all in the centre of product piles; should the autoclave be rotating, the overturning of the product is not guaranteed, which, in fact, could simply slide on the autoclave walls without modifying its exposure to steam. In both cases, however, the probability that the steam comes inside small piles, which usually do not separate, is very low.

• High energy expenditure: in addition to low effectiveness of heat exchange, also the continuous alternating of starting and stopping the cycle, apart from the long cycle times, negatively affect the energy requirement which the system requires in its operation;

• Impossibility of processing products which cannot be ground before cycle: there are some products which, for several reasons, cannot be ground outside the cycle. This surely involves heat exchange uncertainty, as described in the previous points, since the failed reduction of material into portions with small sizes, for example by grinding, involves the impossibility for the steam to reach all portions of the product to be processed itself.

• Excessively high cycle times: indeed as conceived and described previously, by working discontinuously, the nearest known technology involves surely longer cycle times if compared to systems which work continuously; in fact the times for opening and closing the opening/closing systems, the cleaning of the coupling and sealing elements, the replacement of the sealings and the time for the cycle regulation and closing, involve important burdens on time-cycle with respect to systems capable of working continuously.

• Continuous use of personnel for cleaning procedures: by working discontinuously, the nearest known technology requires unavoidably specific personnel for cleaning procedures. • Gluing of the product to the walls of the sterilizer elements and lack in protection of the same: very often, indeed for the nature of the product to be processed itself and for the thermal conditions thereto the latter was subjected in the process, the gluing of product portions on the walls of the elements constituting the autoclave takes place.

• Difficult possibility of assembling and transporting the system: the closest known technology does not usually arise with the purpose of being disassembled, transported inside containers with standard sizes and assembled again at the site wherein it is provided that the same works.

Attempts of solutions are known providing the continuous operation with respect to the invention provided in the present document, but they result to be less performing, above all in terms of heat exchange and new technical solutions and certainly they do not solve several problems which the subject invention is capable of ensuring.

The document US7931860B1 describes an apparatus for processing waste provided with a heating tower with steam, wherein waste falls by gravity, and with a vaporization chamber of the dragged fluids wherein heat is provided by condition, that is by means of indirect heat exchange. The document US5277136A describes a disinfection system for medical waste wherein an indirect heat exchange between the material to be processed and an operating fluid is provided.

The document JP2001235132 describes a device to discharge the residues of waste incineration. Such documents do not offer useful solutions to increase the heat exchange between material to be processed and operating fluid, in particular do not show solutions allowing to increase and improve the heat exchange in direct contact between material and fluid. Summary of the invention

The technical problem placed and solved by the present invention then is to provide a system for the processing of a material allowing to obviate the drawbacks mentioned above with reference to the known art.

Such problem is solved by a system for the processing of a material according to claim 1 , by a processing plant according to claim 14 and by a processing method according to claim 20.

Preferred features of the present invention are set forth in the depending claims.

The present invention provides some relevant advantages briefly described hereinafter by points.

• It allows to work continuously: just as devised, the system the present patent relates to is capable of working continuously, that is the continuous feeding of the product/material to be processed is provided.

• It does not involve opening/closing doors at the beginning/end of cycle: by working continuously, the devised system does not require to close the door(s) at the beginning of the cycle. In fact, the product to be processed is inserted continuously, without interruptions, thus avoiding the problems described previously and related to the repeated opening and closing of the container.

• It provides high effectiveness of heat exchange: the devised system provides the insertion of the steam required to sterilization from several points so as to configure both counter-current, and external-internal cross-flow, and internal-external cross-flow heat exchange. Moreover, a grinder inside the cycle is provided, which reduces the sizes of the product to be processed, consequently increasing the surface exposed to the heat exchange. Moreover, suitable rotating arms and segments normal to the surface of the advancing device then provide for overturning the product to be processed, so as to avoid the formation of small piles and to allow the steam to reach a considerably higher number of points.

• Reduced energy expenditure: the devised system allows reduced energy requirement, both for the high effectiveness of the heat exchange and the reduced cycle time, and for the missed continuous switching-on and off of the system.

• The presence of a grinder positioned inside the area wherein the steam is present allows the possibility of processing products which cannot be ground before cycle. · Short time: the time-cycle result to be shorter if compared to systems working discontinuously failing all times expected for subsequent opening and closing, apart from those linked to the maintenance, regulation and closure of the cycle.

• It does not provide the continuous use of personnel for cleaning procedures: by working continuously, the devised system does not require personnel specifically for the cleaning procedures.

• It avoids gluing the product/material to the walls of the sterilizer and protects the same: the devised system, in fact, provides the coating with polymeric material (for example Teflon), resistant to high temperatures, to all portions coming in contact with the product to be processed, with the double contemporary purpose of avoiding gluing the latter on the walls of the elements constituting the system and to protect the walls themselves from possible mechanical actions or attacks due to chemical agents contained in the product to be processed. · Easy possibility of assembling, disassembling and transporting: the devised system is devised to be uncoupled in modules, which can be easily transported inside standard containers and re-assembled just as easily and quickly in the place in which it is provided that the system itself works. • The contact speed between product to be processed and fluid can be controlled since it depends upon the rotation speed of the cochlea which in turn can be controlled.

• Possibility of working both under pressure and depression.

Other advantages, features and use modes of the present invention will result evident from the following detailed description of some embodiments, shown by way of example and not with limitative purposes.

Brief description of the figures

The figures of the enclosed drawings will be referred to, wherein:

^■ Figure 1a shows a schematic view in side section of the system according to the invention;

^■ Figures 1b, 1c and 1d show schematic views in section of the system according to the invention;

^■ Figure 2 shows a schematic view in front section of four operation steps of a detail of the system according to the invention in a second embodiment;

^■ Figure 3 shows a schematic view in front section of a detail of the system according to the invention in a first embodiment;

^■ Figure 3a shows a schematic view of a detail of Figure 3;

^■ Figure 4 shows a schematic view of a processing plant comprising the system according to the invention.

The thicknesses and the curvatures represented in the above-mentioned figures are to be meant as purely exemplifying, they are generally magnified and not necessarily shown in proportion.

Detailed description of preferred embodiments

Various embodiments and variants of the invention will be described hereinafter, and this with reference to the above-mentioned figures.

Analogous components are designated in the several figures with the same numeral reference.

In the following detailed description, additional embodiments and variants with respect to embodiments and variants already treated in the same description will be illustrated limitedly to the differences with what already illustrated.

Moreover, the several embodiments and variants described hereinafter are subjected to be used in combination, where compatible.

With firstly reference to Figures 1a, 1b, 1c and 1d, according to an embodiment of the invention a system for the thermal processing is designated as a whole with 1.

The system is configured for continuous thermal processing of a material M by means a heat exchange with an operating fluid, the latter not illustrated by sake of simplicity. Preferably, but not exclusively, the operating fluid can be of steam type, by allowing the system to perform thermal processing of steam sterilization on the material M.

Solutions are not excluded providing alternative operating fluids, for example hot air, useful to implement thermal processes for drying the material, or cold air, useful to implement processes for cooling the material, or gaseous mixtures of other type usable in processes known to the state of art.

The system 1 provides in sequence an inlet unit 2 of the material M, a processing unit 3 of the material M and an outlet unit 4 of the processed material M. In the embodiment illustrated in figures 1a, 1b, 1c and 1d, the inlet unit 2 is formed by a hopper apt to receive the material M and to convey it towards the processing unit 3.

Technically equivalent solutions are not excluded, wherein the inlet unit 2 has different shape from the one schematically illustrated in figures 1a, 1b, 1c, 1d. Advantageously, the processing unit 3 comprises a processing chamber 5. The configuration is so that the material M, once entered the chamber 5, can come in direct contact with the operating fluid, thus allowing a direct heat exchange between the operating fluid and the material M, to the advantage of the processing capability of the system. It is herein specified that in a process of heat exchange by direct contact, the heat exchange takes place between the two substantially immiscible phases, for example a gas and a solid, which come in direct contact. Such heat exchange mode allows to exploit the capability of the gaseous means to reach all portions of solid products having complex geometry, by succeeding in implementing a heat exchange even in product points difficult to be reached. On the contrary, in a heat exchange process with indirect contact, the hot and cold phases are separated by a waterproof surface and there is no mixing of the two phases.

The material M can advance continuously inside the chamber 5 along an advancing direction designated with the reference numeral D and which, substantially, goes from the inlet unit 2 towards the outlet unit 4.

Preferably, the processing chamber 5 is sealingly separated from the inlet unit 2 and the outlet unit 4.

Usefully, the processing chamber 5 can include at least a drainage mouth 34 towards which drainage liquids are conveyed, produced in the chamber 5 during the processing of the material M.

With reference to figures 1a, 1b, 1c, 1d, the drainage mouth 34 is usefully placed in distal position with respect to said outlet unit 4, and the chamber 5 can be slightly tilted, the configuration being such that the produced liquids can flow out by gravity towards the drainage mouth 34.

Preferably, the drainage mouth can include a sealing valve, not illustrated in figures, configured to make the drainage liquids to go out, by preventing an exchange of fluids, in particular of gas, between the chamber 5 and outside.

Advantageously, the processing chamber 5 can include a suction mouth 35 configured to convey air to be extracted from the chamber 5.

In particular, the suction mouth 35 can be connected to a sucking system apt to generate vacuum inside the processing chamber 5. The vacuum conditions, in fact, allow to improve evaporation of the liquids contained in the material M to be processed.

Preferably, the suction mouth 35 is equipped with a sealing valve, not illustrated in figures, configured to pass through only the air to be sucked, by preventing the exchange of fluids between the chamber 5 and outside when suction is not implemented.

With reference to the embodiment of figures 1a, 1b, 1c, 1d, the processing unit 3 comprises a main casing 7 which defines the chamber 5. The main casing 7 has substantially cylindrical development along the advancing direction D.

The casing ends are usefully closed by extremal walls 7a, 7b arranged substantially transversal to the advancing direction D.

Preferably, the extremal walls 7a, 7b are formed by welded flanges. Advantageously, each flange can include a pair of bearings placed in a proximal area 38 in the centre of the flange itself.

Usefully, the bearings can be placed outside the flange, but alternative solutions are not excluded wherein, for example, they can be placed in a penetration area 38 detected substantially in the centre of the flange itself.

Usefully, the casing 7 can be provided with an inlet mouth 8 connected to the inlet unit 2.

Analogously, the casing 7 can be provided with an outlet mouth 9 connected to the outlet unit 4. The configuration is so that, in use, the material M to be processed enters the inlet mouth 8, while the processed material M exits the outlet mouth 9.

Advantageously, the processing unit 3 can include a skirt 10 which surrounds at least part of the casing 7 by defining a first cavity 11.

Moreover, the processing unit 3 comprises introduction means 12, 14, 15 of the operating fluid configured to convey the operating fluid inside the chamber 5 according to at least two directions distinct from each other. Preferably, the two directions, distinct from each other, are chosen at least among the following: a first direction substantially inclined with respect to the advancing direction D and entering towards the centre of the processing chamber 5. The operating fluid, according to this first direction, enters the chamber 5 towards the centre of the same.

Preferably, the first direction can be transversal with respect to the advancing direction D and it allows a heat exchange with the material M in external-internal cross-flow. Advantageously, the operating fluid can be input according to this first direction from several points dislocated along the chamber 5.

A second direction parallel and opposite to the advancing direction D. The operating fluid, according to this second direction enters the chamber 5 in direction contrary to the advancing direction D, by allowing a heat exchange with the counter-current material M.

A third direction substantially inclined with respect to the advancing direction D and exiting the chamber 5. The operating fluid, according to this third direction, enters the chamber 5 from an internal position and it proceeds towards outside. Preferably, the third direction can be transversal with respect to the advancing direction D and it allows a heat exchange with the material M in internal-external cross-flow.

Usefully, the operating fluid according to this third direction is input in the chamber 5 from a substantially axial position. Advantageously, the operating fluid can be inlet according to this third direction from several points dislocated in the chamber 5.

Preferably, the introduction means 12, 14, 15 is configured to convey the operating fluid inside the chamber 5 according to the first direction, the second direction and the third direction at the same time. According to a preferred, but not exclusive embodiment, the introduction means 12, 14, 15 comprises lateral holes, for sake of simplicity not illustrated in the figures, obtained on the processing chamber 5, the configuration being such that, in use, the operating fluid can enter the chamber 5 through the lateral holes by following the first direction. In particular, the fluid introduction means 12, 14, 15 can include a plurality of inlet lateral holes obtained on the casing 7.

Preferably, the casing 7 can include lateral holes along its entire surface and the inlet fluid is conveyed along the first direction by proceeding from the casing 7 towards the inside of the chamber 5. Advantageously, the processing unit 3 is provided with a skirt 10 which surrounds at least part of the processing chamber 5 by defining a cavity 11.

The skirt 10 is usefully provided with at least an inlet 33 therethrough the operating fluid can outflow.

Usefully, the inlet 33 can be provided with a sealed valve, not illustrated in figures, configured to make the operating fluid to enter, by preventing it from outgoing.

The lateral holes formed on the chamber 5 are communicating with the cavity 11.

The configuration is so that, in use, the operating fluid enters the chamber 5 through the lateral holes by following the first direction.

Moreover, the cavity 11 , since it is filled up with operating fluid, can heat the lateral walls of the chamber 5, by reducing the thermal dispersions due to the heat exchange with outside.

Usefully, the skirt 10 is provided with a collecting mouth 36 configured to collect the condensation which forms in the cavity 11.

In case, if it has not been contaminated by the product to be processed, the collected condensate in case can be conveyed in a recirculation line and be re used to produce new operating fluid.

Even the collecting mouth 36 comprises a sealed valve, not illustrated in figures, configured to convey the collected condensation by preventing air, or other gases, from inletting from outside to inside of the cavity 11. Different solutions from the described ones are not excluded, for example wherein there is not a skirt 10 and the lateral holes can be directly connected with channels fed with the operating fluid.

In each case, the operating fluid can be inlet in the processing chamber 5 following a radial direction which goes from outside towards inside of the processing chamber 5. The lateral holes formed on the chamber 5, then, allow a heat exchange in cross-flow from outside towards inside of the processing chamber 5.

Advantageously, the fluid introduction means 12, 14, 15 can include at least one perforated disk 12 located in the processing chamber 5 to close a section of the chamber itself.

The perforated disk 12 can be positioned substantially transversal to the advancing direction D.

Usefully the perforated disk 12 defines an inlet space 13 identified in a substantially proximal position with respect to the outlet unit 4.

In particular, the inlet space 13 is adjacent to the outlet unit 4, but it is not crossed by the material M.

With reference to figures 1a, 1b, 1c, 1d, the perforated disk 12 can be usefully located in the processing chamber 5, downstream of the outlet channel 9, transversally to the advancing direction D so as to define with the side wall 7b the inlet space 13.

The perforated disk 12 can include one or more holes arranged on its surface.

Moreover, the introduction means 12, 14, 15 of the operating fluid can include at least one inlet duct 14 obtained on the chamber 5 and communicating with the inlet space 13.

Usefully, the inlet duct 14 can be provided with una sealed valve, not illustrated in figures, configured to make the operating fluid to enter the chamber 5 by preventing the gas from outgoing from the chamber 5 towards outside. Preferably, the inlet duct 14 is obtained on the casing 7 near the inlet space 13, between the perforated disk 12 and the extremal wall 7b.

The configuration is so that, in use, the operating fluid conveyed by the inlet duct 14 enters the inlet space 13 and then outgoes through the perforated disk 12 in the chamber 5 by following the second previously described direction.

In this way the operating fluid can be input in the processing chamber 5 by following a direction parallel and contrary to the advancing direction D. The perforated disk 12 and the inlet duct 14, then, allow a counter-current heat exchange.

Advantageously, the introduction means 12, 14, 15 comprises a hollow shaft, perforated at least for a portion in length, designated with the reference numeral 15. The perforated shaft 15 is at least partially inserted in the chamber 5 in a position substantially parallel to the advancing direction D and it has an inlet mouth 16.

With reference to figures 1a, 1b, 1c, 1d, the perforated shaft 15 can pass through the extremal portions 7a, 7b, partially outgoing therefrom so as to define two external portions of shaft 15a and 15b. In the present embodiment the inlet mouth 16 is obtained at the external portion 15b, as illustrated in figures 1a, 1b, 1c, 1d, but different solutions are not excluded, wherein, for example, it is positioned elsewhere along the external portion 15b or along the external portion 15a.

Preferably, the perforated shaft 15 can be positioned in conjunction with the central axis of the processing chamber 5. In particular, the perforated shaft 15 can be positioned in conjunction with the central axis of the casing 7, the latter being substantially cylindrical.

Usefully, the perforated shaft 15 can have holes along its entire length inside the chamber 5. The configuration is so that, in use, the operating fluid is conveyed through the inlet mouth 16 in the perforated shaft 15 and by the perforated shaft 15 inside the processing chamber 5 by following the third previously described direction.

In this way the operating fluid can be input in the processing chamber 5 by following a radial direction starting from an axial position and going towards outside. The perforated shaft 15, then, allows a cross-flow heat exchange from inside towards outside of the chamber 5. Moreover, the system 1 comprises advancing means configured to move the material to be processed along the advancing direction D inside the processing chamber 5.

The configuration is so that the material M enters and exits with continuity in/from said chamber 5, advancing along the advancing direction D and exchanging heat with the operating fluid according to the directions distinct from each other and described previously.

In the present embodiment, the advancing means, designated with the reference numerals 15 and 17, can include a screw-type device 17 at least partially inserted in the processing chamber 5.

The screw-type device 17 can be provided with a drive shaft 15 at least partially inserted longitudinally in the chamber 5 in a position substantially parallel to the advancing direction D.

Usefully, the drive shaft 15 coincides with the perforated shaft 15, but solutions are not excluded wherein the drive shaft 15 and the perforated shaft are distinct from each other, for example two concentric shafts.

As schematically illustrated in figures 1a, 1b, 1c, 1d the drive shaft 15 can be connected to an engine unit 22. In this way the drive shaft 15 can be actuated in rotation around an axis substantially parallel to the advancing direction D. With reference to figures 1a, 1b, 1c, 1 d, the drive shaft 15 crosses the walls 7a and 7b, it is supported by the bearings placed in the penetration area 38 of such walls and it can be rotated indeed by the effect of the bearings. Advantageously, the penetration area 38 of the side walls 7a and 7b, therethrough the drive shaft 15 passes, is suitably provided with sealing means which prevent gas from outgoing from and entering the processing chamber 5.

Preferably, the screw-type device 17 comprises advancing coils 18 keyed to the drive shaft 15 and, in use, designed to push the material along the advancing direction D.

When the drive shaft 15 is rotating, the advancing coils 18 are dragged in rotatory motion and the material M pushed along the advancing direction D. Usefully, the advancing coils 18 can be perforated, the configuration being such that the operating fluid can pass through the coils 18. The holes of the advancing coils 18 can be sized so as to prevent the material M from passing, by allowing the passage to the operating fluid only. Preferably, the screw-type device 17 can include a delimitation disk 37. Advantageously, the delimitation disk 37, together with the perforated disk 12 defines two ends for the helical development of the coils 18.

The delimitation disk 37 can be perforated, configured to make the air to be sucked to pass. The coils can further have different pitch in the several points inside the casing 5, so as to modify, if needed, the advancing speed of the material.

Usefully, the perforated disk 37 is located in the chamber 5 to close a section of the chamber 5 substantially transversal to the advancing direction D and it is located in distal position with respect to the outlet unit 4, upstream of the inlet unit 2.

Different embodiments with respect to the described one are not excluded, for example wherein the advancing means comprises a plurality of conveyor belts arranged in series and at decreasing levels along the direction D, or a series of inclined belt conveyors wherein the material M is made at first to rise and then left to fall down on the subsequent belt, or solutions which provide the use of rollers.

Advantageously, the system 1 comprises sealed inlet means of the material M. The sealed inlet means is schematically illustrated in figures 1a, 1b, 1c, 1d and designated with the reference numeral 6. The sealed inlet means 6 is interposed between the inlet unit 2 and the processing unit 3 and between the processing unit 3 and the outlet unit 4, configured to intercept said material from one of the units 2, 3 and to transfer it to the next unit 3, 4 by maintaining the units 2, 3 ,4 atmospherically separated. In this way the chamber 5 results to be sealingly separated from the inlet unit and the outlet unit 4. Thanks to the sealed inlet means 6 the material M can enter/outgo with continuity in/from the chamber 5 without the atmospheric conditions thereinside being subjected to drastic changes. In fact, the gas exchange with outside through the inlet unit 2 and the outlet unit 4 results to be prevented by the sealing action of the inlet means 6.

According to an embodiment illustrated in figure 3, the sealed inlet means 6 is of the type with valves having rotating sectors 23, configured in such a way that each sector 23 is alternatively communicating: with the inlet unit 2 or with the chamber 5, in case the valve is interposed between the inlet unit 2 and the chamber 5, or with the chamber 5 or with the outlet unit 4, in case it is interposed between the chamber 5 and the outlet unit 4.

Upon considering the valve 6 interposed between the inlet unit 2 and the chamber 5, a sector 23 can rotate until being in communication with the inlet unit 2, therefrom it receives material M. By continuing the rotation, the sector 23 changes position until coming into communication with the chamber 5, by herein conveying the material M.

Analogously, upon considering the valve 6 interposed between the chamber 5 and the outlet unit 4, a sector 23 can rotate until being in communication with the chamber 5, therefrom it receives processed material M. By continuing the rotation, the sector 23 changes position until coming into communication with the outlet unit 4, by herein conveying the processed material M.

In the embodiment illustrated in figure 3, the valve 6 can include a plurality of dividing elements 24 and a connecting wall 28 configured to be interposed between units to be kept atmospherically separated.

By way of example, the connecting wall 28 is interposed between the inlet unit 2 and the processing chamber 5, but analogous considerations can be made in case the connecting wall 28 is interposed between the chamber 5 and the outlet unit 4.

The dividing elements 24 are hinged to a rotation centre 25 and arranged on staggered angular positions. Each sector 23 is detected by two adjacent dividing elements 24.

In figure 3 four dividing elements 24 are illustrated, defining as many sectors 23, but different embodiments are not excluded, having a different number of sectors and a different number of dividing elements 24. In distal position from the rotation centre 25, each dividing element 24 comprises a sealing head 26 provided with at least a sealing element 27, the configuration being such that, in use, the sealing element 27 is placed in contact with the connecting wall 28 sealingly.

Usefully, the sealing element 27 can be a segment made of rubber resistant to high temperatures. The rubber segment 27 extends for the whole width of the connecting wall 28.

Preferably, the sealing head 26 can include two sealing elements 27 sandwich like coupled and interspersed by a support 29 extending from the separating element 24. Embodiments are not excluded providing a different number of sealing elements 27, even greater than two.

The sealing head 26 further comprises an elastic element 27a which, in use, is placed in contact with the connecting wall 28. The elastic element 26a, preferably, can be a sheet made of steel. This is sufficiently thin to guarantee an elasticity so as to allow the elastic element to deform and adapt to the shape of the connecting wall 28.

Advantageously, the processing unit 3 can include auxiliary processing means 19, 20, 21 configured to process mechanically the material M.

In particular, the auxiliary processing means 19, 20, 21 can include at least a grinding device 19 located upstream of the advancing means 15, 17.

The presence of the grinding device 19 allows to grind and move the material M inletting the chamber in case a dimensional homogenization of the material itself is required, or in case it is requested that the material M is reached by the operating fluid in the largest number of reachable points. With reference to figures 1a, 1b, 1c, 1d, the grinding device 19 can be placed in the chamber 5 upstream of the advancing means 15, 17.

More particularly, the grinding device can be placed in the inlet channel 8. The inlet channel 8 can include inspection doors, for sake of simplicity not illustrated in figures, which allow to access the upper and lower portion of the grinding device 19, by allowing to perform possible maintenance/cleaning procedures on the same.

Preferably, the auxiliary processing means 19, 20, 21 can include tilting elements 20, 21. A first type of tilting elements, designated with the reference numeral 20, can be keyed to the drive shaft 15. The tilting elements 20 can be of the type of arms, arranged substantially inclined with respect to the advancing direction D, preferably transversal thereto.

The arms allow to overturn the material M to be processed during its whole advancing, by improving then the heat exchange, both as the formation of piles of material is avoided, which would not allow the operating fluid to come inside thereof, and as they would vary the exposed faces of the material M to be processed.

Alternative embodiments are not excluded wherein the arms 20 are keyed to the walls of the chamber 5 and arranged so as to not interfere with the advancing coils 18.

A second type of tilting elements, designated with the reference numeral 21 , can be welded to the tilting elements 20 or to the advancing coils 18, or to both of them. Preferably, they can be welded in a position substantially parallel to the advancing direction D. Solutions are not excluded wherein the tilting elements 21 are inclined with respect to the advancing direction D.

Preferably, the tilting elements 21 can be implemented with sheet segments positioned normal to the surface of the coils 18 and placed at reduced distance from the bottom. They contribute, together with the tilting elements 20, to overturn the product to be processed during its whole advancing and thus to improve the heat exchange. Advantageously, the system 1 can include quick attachment means (such as for example flanged attachments), the configuration being such that the system 1 can be assembled/disassembled in a modular way.

The inlet unit 2, the processing chamber 5 and the outlet unit 4 can be assembled and disassembled easily in modular way.

In particular, the inlet units 2, the processing chamber 5 and the outlet unit 4 can be joined by means of flanged attachments or other technically equivalent connecting elements. An alternative embodiment is wholly analogous to the previously described one and it is characterized in that the sealed inlet means 6 is of the type of double dump valves.

The double-dump valves 6 are configured to be alternately communicating: with the inlet unit 2 or with the chamber 5, in case the valve is interposed between the inlet unit 2 and the chamber 5, or with the chamber 5 or with the outlet unit 4, in case it is interposed between the chamber 5 and the outlet unit 4.

In figure 2 a possible double-dump valve 6 is schematically illustrated, by way of example interposed between the inlet unit 2 and the processing chamber 5. The same considerations apply also in case the valve is interposed between the chamber 5 and the outlet unit 4.

The double-dump valve 6 can include a separating space 38 alternatively communicating with the inlet unit 2 and with the processing chamber 5. In particular, the double-dump valve 6 comprises sealing means 39a, 39b movable between an opening configuration, wherein they allow the passage of material M, and a sealing configuration, wherein they prevent the passage of material and gas.

In particular, first sealing means 39a is interposed between the inlet unit 2 and the separating area 38, whereas second sealing means 39b is interposed between the separating area 38 and the processing chamber 5. The configuration is so that: when the first sealing means 39a is open, the second sealing means 39b is sealingly closed and the separating area 38 is communicating with the inlet unit 2 therefrom it receives the material to be processed M; when the second sealing means 39b is open, the first sealing means 39a is sealingly closed and the separating area 38 is communicating with the processing chamber 5 towards which the material M is conveyed.

The double-dump valve 26 is usefully provided with at least a bypass channel 43b configured to put into communication the separating area 38 with the processing chamber 5 when both sealing means 39a, 39b are closed.

In this way it is possible to create in the separating area 38 the atmospheric conditions of the chamber 5 before the material M is sent in the chamber itself. Such feature allows to keep separated atmospherically the inlet unit 2 and the processing chamber 5. The double-dump valve 6 can further include an auxiliary bypass channel 43a configured to put into communication the separating area 38 with the inlet unit 2 when the separating means 39a, 39b are closed.

In this way it is possible to start heating the material M as from the inlet unit 2, by increasing the thermal effectiveness of the processing.

An additional embodiment is wholly analogous to the previously described ones, but it is characterized in that the screw-type device 17 is of open type.

In particular, the screw-type device 17 comprises a drive shaft 15 like the previously described one and two extremal disks, coincident with perforated disk 12 and the separating disk 37, keyed to the drive shaft 15 and, then, dragged in motion by the latter. The advancing coils 18 are welded to the disks 12, 37 and not to the shaft.

The previously described system 1 can be operatively inserted in a thermal processing plant 1a like the one schematically illustrated in figure 4.

The processing plant 1a comprises the system 1 for the thermal processing previously described in several embodiments.

The plant 1a can include a fluid generator 30 operatively connected to the processing unit 3 and configured to send, in use, the operating fluid into the chamber 5. Advantageously, the fluid generator 30 can be operatively connected to the inlet mouth 16 of the perforated shaft 15.

Analogously, the fluid generator 30 can be operatively connected to the inlet duct 14.

Analogously the fluid generator 30 can be operatively connected to the inlet 33. Preferably the fluid generator 30 can be of the type of a steam generator, so that the plant 1a can implement steam thermal treatments.

The plant 1a can further include a conveyor system 40 of material configured to send material to the inlet unit 2.

The conveyor system 40 can be chosen among any system known to the state of art, for example a system with belts and pulleys which can be loaded with the material M, or a drop transport system, or a roller or screw transport system.

Advantageously the plant 1a can include a control unit, schematically represented in figure 4 and designated with the reference numeral 50.

The control unit 50 can be operatively connected to at least the system 1 and configured for the management and partial or total control of the system 1.

In a preferred embodiment, the control unit 50 can be provided with an electrical panel configured to supply electricity to all organs and devices of the system 1 and possible other organs and devices of the other systems of the plant 1a. The control unit 50, moreover, can be provided with a control panel configured to coordinate and manage all organs and devices of the system 1 and possible other organs and devices of the other systems of the plant 1 a.

Preferably, the plant 1a can include a condensate collection unit 31 connected to the system 1 and placed along a condensate recirculation line C which goes from the system 1 to the fluid generator 30.

The condensate collection unit 31 collects the condensation produced in the system 1 and it conveys it to the fluid generator 30.

Usefully, the condensate collection unit 31 is of the type of a tank.

The operating fluid introduced in the cavity 11 , which does not come in direct contact with the material M to be processed, gradually cools down and changes state by condensing and accumulating in the low portion of the skirt 10 to be then extracted through the collecting mouth 36 and conveyed in the tank 31 for collecting condensations.

The condensations then could be transferred cyclically to the fluid generator 30, reintegrated with the steam amount used by direct contact with the product to be processed.

Advantageously, the plant 1a can include a drainage collection unit 32 operatively connected to the system 1 and configured to collect waste liquids deriving from the processing of the material M.

The drainage collection unit 32 is configured to receive and accumulate all liquids which form during processing. They will be then extracted, for example through a pump, once reached the maximum level acceptable by the unit 32. These liquids, according to their composition, will be then discharged or re used, after possible specific processing.

The drainage collection unit 32, usefully, can include an accumulation tank. Preferably, the plant 1a can include a vacuum generation system 41 operatively associated to the system 1 and configured to suck air from the processing chamber 5.

Advantageously, the plant 1a can include an air suction and treatment system 42 configured to suck and treat air and other gases coming from the system 1. In particular, the air treatment system 42 can include a suction hood 43 connected to an air processing unit, schematically designated with the reference numeral 45.

The air treatment system 42 can further include a suction fan 46 connected to the suction hood 43, for example by means of a suction duct 44. The suction fan 46 is configured to suck, through the suction hood 43, air, odours and gases possibly coming from the system 1 and then to send them to the air processing unit 45.

In the air processing unit 45, the air is processed, for example by scrubbing or other filtering and cleaning processes, before being re-introduced into the atmosphere.

The operation of the above-described system 1 and/or of the plant 1a, in case of a steam sterilization processing, is the following.

Following the flow of the material M, this is inserted (with any feeding system, for example conveyor belts, screws, etc.) continuously through the inlet unit 2, for example a hopper in an interception system, which allows to separate the external environment from the internal one which provides an atmosphere in which there is steam under conditions required to the cycle, however by avoiding discontinuity in the insertion of the product itself. The interception system substantially coincides with the sealed inlet means 6. Once exceeded the interception system, in case there is a grinding device 19, the product crosses the inlet channel 8, which is also the inspection channel of the grinding device 19 immediately downstream, in which the material can be minced. The channel 8, in fact, provides an inspection door to access the inlet of the grinder, with the purpose of performing possible maintenance procedures. The position of the grinding device 19 inside the section with steam atmosphere, then not in contact with the external environment, allows the sterilization even of all products which otherwise, for any reason, could not be ground outside.

Once minced, the material M enters the chamber 5, in which it is made to advance by means of the screw-type device 17 and it is overturned and then separated, both by specific arms 20, and by blades 21, which consist in sheet segments welded to the arms 20 and to the surface of the screw-type device 17 in normal manner. Both the screw 17 and the overturning arms 20 are connected stiffly (for example by welding) to the rotating and perforated hollow shaft 15 and they are integral thereto in its rotating motion. The perforated shaft 15 rested onto a pair of the bearings, is made to rotate by means of the engine unit 22 (any system capable of generating rotary motion) thereto it is coupled and it is crossed inside by the vapour produced by the generation system 30 and inserted in the shaft through a rotating valve 16, which connects the rotating shaft 15 to a steam supply pipe from the steam generation system 30 to the shaft itself. The steam then outgoes from all holes applied on the shaft 15 in the whole length inside the chamber 5, by running over the product in cross-flow from inside to outside, along the whole sterilization path, by constituting the first mode of possible heat exchange in the subject system.

The rotation speed of the perforated shaft 15, and then of the screw integral directly or indirectly thereto, and, then, the advancing speed of the product inside the chamber 5 is strictly linked to the residence time for which the product has to be subjected so that it can be defined “sterilized” at the end of cycle.

Outside the processing chamber 5, there is a skirt 10. In the cavity 11 the steam is inserted through suitable inlet 33, with the double purpose of maintaining the heat inside the chamber 5 (acting as insulating layer) and that of making the steam to enter inside the chamber 5 through holes made on the surface of the same for its whole inner useful length by running over the product to be processed in cross-flow from outside to inside, along the whole sterilization path and, then, constituting the second contemporary mode of possible heat exchange in the subject system.

The condensations which form at first are accumulated in the low portion of the skirt 10, to be then drained through suitable mouth 36 and drainage system, accumulated in the condensation collection tank 31 and re-input into the steam generator 30 to re-start the cycle.

At the ends of the screw-type device 17, disks 12, 37 for each side creates a separation chamber between the screw beginning and the extremal walls 7a, 7b of the chamber 5; the steam is inserted through suitable inlet duct 14 in the chamber 5, acting as collector, on the product outlet side and, through holes made on the whole surface of the disk 12 and in case even on all coils 18 of the screw 17, it runs over the counter-current product, constituting the third contemporary mode of possible heat exchange in the subject system.

On the opposite side in case even a sucking mouth 35 can be provided for connecting the chamber 5 to a vacuum system 41 , which would reduce the pressure inside the chamber in order to ease evaporation of the liquids contained in the material M.

At the final portion of the screw-type device 17, an opening on the low portion allows the outflow of the material M which is conveyed to sealed inlet means 6 allowing to extract continuously the sterilized material M by keeping separate the chamber 5 from the external environment.

The whole system 1 is located slightly inclined, so that the tilting allows to convey the liquids which have formed inside the sterilizer towards the drainage mouth 34 placed on the inlet side of the material M, between the disk 37 the extremal wall 7a therethrough they are drained by a means of a drainage system 32 and accumulated in a tank to be then disposed of not before possible processing.

As additional improvement, the supporting structure of the whole system can be divided into portions, which can be easily disassembled in bulk and inserted in standard containers with the purpose of being transported and re-assembled just as simply once at destination; the highest section of the structure can include both the air treatment system 42 for capturing possible gases, odours or small steam losses, and a possible crane allowing to perform in a facilitated way some challenging maintenance procedures. All elements subjected in some way to heat are obviously insulated with the double purpose of minimizing both the thermal dispersion towards environments at lower temperature and protecting in case of possible contacts.

All moving organs are synchronized therebetween and, preferably, controlled through the control unit 50 which coordinates them, above all with the purpose of making that, depending upon the sizes (particularly of the screw length), the residence time of the product to be processed inside the chamber 5 results to be the one necessary and sufficient, so that the outflowing material M has obtained the wished sterilization level.

A process for the thermal treatment of material is described hereinafter.

The process comprises a phase wherein a system 1 is to be provided, as the one described previously, configured for continuous thermal processing of a material M.

The process, then, provides an inlet phase comprising the continuous insertion of material M to be processed in the processing chamber 5.

Subsequently, the process provides a heat exchange phase comprising the continuous advancing of the material M along the advancing direction D while an operating fluid is inserted in the processing chamber 5 according to at least two directions distinct from each other therealong a heat exchange between the material M and the operating fluid takes place.

In particular, in the heat exchange phase the operating fluid can be inserted in the processing chamber 5 according to at least two of the following directions therealong the heat exchange takes place: a first direction substantially inclined with respect to said advancing direction D and entering said processing chamber 5; a second direction parallel and opposite to the advancing direction D; and a third direction substantially inclined with respect to said advancing direction D and exiting the processing chamber 5.

The process, at last, comprises an outlet phase comprising a continuous extraction of the material M processed by the chamber.

Other process phases can be taken from the above-mentioned description of the system 1 for the thermal processing and from the processing plant 1a. The present invention has been sofar described with reference to preferred embodiments. It is to be meant that other embodiments belonging to the same inventive core may exist, as defined by the protective scope of the herebelow reported claims.