Transportation device, transportation method and system for recycling of a collection

Abstract

A conveying device (1) for conveying flowable material, comprising a screw conveyor (2) for collecting fluid from a collection area (P) and transporting the fluid to a destination area (S). The screw conveyor (2) comprises a screw (2a) coiled around a shaft (2b) extending along a longitudinal axis and an outer casing (2c) at least partially housing the screw (2a). The screw (2a) has a plurality of turns (2d). The outer casing (2c) has an inner surface (2e) facing a respective head surface of at least some of the turns (2d). Between two consecutive turns and the outer casing (2c) there is a compartment (V1, V2). The outer casing (2c) is at least partially made of a deformable polymeric material, so that when a solid particle (PS) of flowable material conveyed by the screw (2a) is interposed between a head surface of a turn (2d) and the inner surface (2e) of the outer casing (2c), the outer casing (2c) radially and reversibly deforms towards the outside to allow the solid particle (PS) to pass between the head surface (2f) of the turn and the inner surface (2e) of the outer casing (2c) to be transferred from one compartment (V1) to another compartment (V2) adjacent to said compartment (V1).

Description

TECHNICAL FIELD

[0001] The present invention relates to a transport device and method for transporting flowable material. BACKGROUND

[0002] The flowable material that can be transported by means of the device and method according to the present invention can be a fluid comprising a liquid portion and a solid portion. In particular, the fluid can comprise a liquid inside which there are solid particles of different sizes from each other, for example a fluid comprising water with concrete residues dispersed inside.

[0003] Alternatively, the fluid that can be transported by means of the device and method according to the present invention can be a loose solid material, i.e. comprising powders and / or granules and / or fragments of different sizes from each other.

[0004] In particular, the device and method according to the present invention can be used to convey towards a concrete separator a fluid comprising a liquid with concrete residues inside, for the recovery of the aggregate material dispersed in the liquid. This liquid can come from a truck mixer arranged to prepare concrete and transport it to a construction site, or from a production plant of precast concrete products.

[0005] Furthermore, the present invention relates to a system for the recovery of aggregate of concrete residues, comprising the transport device described above.

[0006] Separation plants, also known as concrete separators, are known, which allow the recovery of aggregate from excess concrete still unused on truck mixers or from washing liquids used to wash the truck mixers or other equipment for handling concrete.

[0007] Many truck mixers that distribute concrete during the day at construction sites operate in systems for the recovery of aggregate. In the evening, once the operations of transporting concrete to the construction sites are finished, the truck mixers must be cleaned to remove the concrete residues present in these truck mixers.

[0008] Therefore, the truck mixers are subjected to a washing operation, during which the concrete is diluted in the truck mixers by introducing inside them an amount of water usually in a 1 : 1 ratio with the concrete present in the truck mixers.

[0009] Once the washing is completed, each truck mixer discharges into the tank of the recovery system the remaining concrete contained in the truck mixer diluted in the washing water.

[0010] Production plants for the production of precast concrete elements comprise a concrete mixer and a plurality of carriers that receive the concrete from the mixer and transport it inside the plant to pour it into suitable frames.

[0011] At the end of each daily production cycle, the mixer and the carrier are washed to remove the concrete residues remaining inside them. The washing operation generates a liquid in which concrete residues are contained, which can be poured into the tank of the recycling system, so that the residues can be recovered.

[0012] The transport device is in fluid communication with the tank of the recycling system.

[0013] The transport device can be of the type disclosed in international patent application No. WO 2016 / 079635.

[0014] The transport device is activated to transport the concrete and water, i.e. the fluid containing the aggregates to be recovered, from the tank to the separation plant. The transport device is usually equipped with a screw conveyor comprising a tubular casing and a screw housed in the casing. The screw comprises a plurality of turns, the head surface of which is in contact with the inner surface of the tubular casing. The transport device is thus able to transport not only solids but also water upwards.

[0015] It can happen that solid particles, for example sand, get stuck between the screw and the casing. If this happens, there is a high risk of damaging the tubular casing or damaging the screw. For example, the solid particles stuck between the screw and the casing can scratch the inner surface of the tubular casing, or can permanently deform the tubular casing, or can create cracks on the surface covering the tubular casing, through which the liquid can penetrate. In the latter case, the liquid, which is often corrosive, can come into contact with materials that are not suitable to interact with it, thus causing rust phenomena and / or the cracks to gradually widen. In the long term, this has a negative impact on the efficiency of the transport device.

[0016] Furthermore, in order to allow the transport device to continue operating even in the event that solid particles get stuck between the screw and the casing, a high installation power is required to cope with the power peaks required to disengage the solid particles. For this reason, the systems of the prior art are not very sustainable from an energy point of view.

[0017] Furthermore, another drawback of the transport devices of the prior art is the high level of noise. For example, some of the casings of the prior art are made of metal material, which produces a lot of noise during the transport of the concrete residues.

[0018] If the transport device is used to transport a liquid containing concrete residues, the characteristics of the solid and liquid parts of the material to be transported highlight a key aspect of the device, more specifically, the fact that sand, sand, chemicals and liquid aggregates must be lifted.

[0019] Similar defects can arise when a transport device of the type described above is used to transport loose materials composed of solid particles in the form of powders and / or granules and / or fragments having different sizes.

[0020] WO 2009 / 047811, filed by the same applicant as the present application, discloses a transport device comprising a screw conveyor, inside the outer casing of which a screw is rotated by a motor. The transport device further comprises a resilient support placed between the outer casing and the screw and which can be made of a plastic material such as polyurethane. According to the disclosure of WO 2009 / 047811, the resilient support is helpful if aggregate material is inserted between the screw and the support. In this case, a slight elastic deformation occurs which facilitates the passage of the aggregate material.

[0021] The support disclosed in WO 2009 / 047811 has a plurality of ribs provided on the surface of the support facing the outer casing. The ribs rest against the casing.

[0022] When using the transport device disclosed in WO 2009 / 047811 for transporting aggregate, it can happen that solid particles get jammed between the support and the screw. If the solid particles get trapped between the support and the screw at a point of the support which is very close to the ribs, where the support has a relatively high stiffness due to the presence of the ribs, the solid particles can cut the support and penetrate the thickness of the support. This leads to a rapid wear and tear of the support, which reduces the efficiency of the transport device and can require stopping the transport device to replace the damaged support with a new one. It is therefore a technical purpose of the present application to provide a transport device for flowable material, a method for transporting flowable material and a system for recycling aggregate which are able to overcome the drawbacks of the prior art.

[0023] It is a purpose of the present application to improve the prior art transport devices for transporting flowable material, such as a fluid comprising a solid fraction and a liquid fraction, for example a liquid comprising water with dispersed concrete residues, or such as a loose material comprising solid particles in the form of powder and / or granules and / or fragments.

[0024] It is a further purpose to reduce the risk of deformation and / or damage of the casing and / or of the screw in prior art systems suitable for transporting a fluid comprising a liquid fraction and a solid fraction, in particular a liquid with dispersed concrete residues, or suitable for transporting a loose material comprising solid particles in the form of powder and / or granules and / or fragments.

[0025] It is a further purpose to provide a transport device for transporting flowable material which allows reducing the installation power.

[0026] It is a further purpose to provide a transport device for transporting flowable material which is able to operate with reduced noise.

[0027] The indicated technical objects and the specified aims are substantially achieved by a transport device, a transport method and a system for recycling of a collection of material, comprising the technical characteristics described in one or more of the attached claims. The dependent claims correspond to possible embodiments of the application.

[0028] In a first aspect of the application, a transport device for conveying a flowable material is provided, the device comprising a screw conveyor for collecting a fluid from a collection zone and transporting the fluid towards a destination zone, the screw conveyor comprising a screw coiled on a shaft extending along a longitudinal axis and a casing at least partially housing the screw, the screw having a plurality of turns, the casing having an inner surface facing respective head surfaces of at least some of the plurality of turns, a compartment being defined between two consecutive turns of the plurality of turns and the casing, wherein the casing is at least partially made of a deformable polymeric material, such that, when a solid particle of the flowable material conveyed by the screw is interposed between a head surface of one of the plurality of turns and the inner surface of the casing, the casing radially and reversibly deforms towards the outside to allow the solid particle to pass through between the head surface of the turn and the inner surface of the casing to transfer from one compartment to another compartment adjacent to the compartment.

[0029] Thanks to the radial and reversible deformation of the casing, the solid particle that can be jammed between the casing and the head surface of the turn can easily enter into the other compartment adjacent to the compartment, for example into the other compartment preceding the compartment, without damaging the screw and / or the casing.

[0030] In an embodiment, the casing is an outer casing of the transport device.

[0031] By manufacturing the outer casing with a deformable polymeric material, the outer casing can radially and reversibly deform towards the outside when a solid particle of the flowable material conveyed by the screw is interposed between a head surface of a turn and the inner surface of the casing, without the need to use the elastic support disclosed in WO 2009 / 047811. In other words, no elastic support is interposed between the outer casing and the screw, since the outer casing directly faces the screw.

[0032] The risk of damaging the components surrounding the screw is thus greatly reduced, since the outer casing can freely expand radially at least in the effective transport zone where the flowable material conveyed by the screw is accumulated during transport. Thus, in the event of a solid particle jammed between the deformable outer casing and the screw, the outer casing is able to freely deform towards the outside so that the solid particle can pass between the head surface of the screw and the inner surface of the casing.

[0033] In other words, at least in the active zone, the outer shell elastically flexes in a uniform manner in the radial direction. In one embodiment, the turns of said plurality of turns are made of a deformable polymeric material, so as to reversibly bend when a solid particle conveyed by the helix is interposed between the head surface of one of the turns of said plurality of turns and the inner surface of the shell.

[0034] In one embodiment, the head surfaces of the turns of said plurality of turns are parallel to the inner surface of the shell, so that the head surfaces perform a certain wiping action on the inner surface of the shell during rotation of the helix.

[0035] Thanks to this wiping action, the helix wipes the inner surface of the shell while the helix elastically deforms.

[0036] The shell also elastically deforms and, during the relative elastic return, cooperates with the helix to project the solid particle towards the center of the adjacent compartment.

[0037] This makes it possible to avoid blockages, malfunctions and losses of efficiency of the transport device.

[0038] Since the shell and / or the helix quickly recover their initial shape after their transient deformation, the contact between the head surface of the turns and the inner surface of the shell can be substantially immediately restored. This contact does not change over time, which allows the transport device to remain highly efficient at all times, even and particularly in the case where the longitudinal axis of the transport device is inclined, i.e. the transport device allows flowable material to be transported from a lower collection zone to a higher destination zone. Effectively, by keeping the shell in contact with the head surface of the turns at all times, it is possible to prevent any backflow of the liquid part of the flowable material, which would reduce the efficiency of the transport device.

[0039] In a second aspect of the application, a method is provided, comprising the steps of:

[0040] introducing flowable material into a collection zone;

[0041] providing a transport device comprising a helical conveyor, the helical conveyor comprising a helix and a shell, the helix being wound on a shaft extending along a longitudinal axis, the shell at least partially housing the helix, the helix having a plurality of turns, the shell having an inner surface facing respective head surfaces of at least some of said plurality of turns, a compartment being defined between two consecutive turns of said plurality of turns and the shell, the shell being at least partially made of a deformable polymeric material;

[0042] transporting the fluid from the collection zone to a destination zone by using the transport device;

[0043] wherein, during the conveying step, when a solid particle of said flowable material conveyed by the screw is interposed between the head surface of one turn of the plurality of turns and the inner surface of the casing, the casing is locally radially and reversibly deformed towards the outside, so that said solid particle passes through between the head surface of the turn and the inner surface of the casing to pass from one compartment to another compartment adjacent to said compartment.

[0044] In one embodiment, a system for recovering aggregates from a flowable material consisting of a fluid containing concrete residues is provided, comprising a tank for containing said fluid in which the aggregates to be recovered are dispersed, and a conveying device according to the first aspect of the application, wherein the screw conveyor is configured for collecting the fluid from the tank and conveying the aggregates to be recovered and the liquid portion of the fluid from an upstream portion to a downstream portion of the screw conveyor.

[0045] Further features and advantages of the present application will become more apparent from the following non-limiting description of non-exclusive embodiments of a conveying device, a conveying method and a system for recovering aggregates.

[0046] The following description is made with reference to the accompanying drawings, which are provided by way of illustration only and thus are not restrictive of the present application, in which:

[0047] - Figure 1 is a schematic view of an apparatus comprising a conveying device in a system for recovering aggregates;

[0048] - Figure 2 is a perspective view of some internal components of the conveying device of Figure 1 ;

[0049] - Figure 3 is a schematic cross-sectional view of the conveying device of Figure 2 ;

[0050] - Figures 4A to 4C is a schematic view of the operation of the conveying device according to the present application.

[0051] With reference to the accompanying drawings, reference number 1 as a whole denotes a conveying device for transporting concrete residues, which will be referred to hereinafter for simplicity of description as device 1.

[0052] Device 1 comprises a screw conveyor 2 for transporting a flowable material collected from a collection area "P".

[0053] In the example shown, the flowable material comprises a fluid containing concrete residues.

[0054] More specifically, the fluid comprises a liquid portion (e.g. water) and a solid portion mainly composed of aggregates (sand and gravel). In addition to the above-mentioned aggregates, the solid portion can also comprise debris formed by deposits or chunks of solidified material deriving from the solidification of the material of the concrete. More generally, the solid portion comprises solid particles, which will be referred to as "PS" in the following.

[0055] The screw conveyor 2 is configured for collecting the fluid from a collection area "P", which can for example comprise a tank 3 into which one or more truck mixers discharge the fluid contained in the drum of the truck mixers. Alternatively, the fluid, which is a washing liquid coming from components of a system for producing precast concrete, can be discharged into the tank 3.

[0056] The screw conveyor 2 is also configured for transporting the fluid towards a destination area "S", for example in which a separation device (not shown) can be positioned, which is configured for separating the solid portion from the liquid portion of the fluid.

[0057] As shown in Figure 2 and Figure 3 , the screw conveyor 2 comprises a helix 2a coiled around a shaft 2b extending along a longitudinal axis Z. The screw conveyor 2 also comprises an outer casing 2c, inside which the helix 2a is at least partially housed. The term "at least partially housed" means that the helix 2a can also be only partially housed in the casing 2c in the longitudinal direction and in the radial direction.

[0058] The shaft 2b is straight and extends from the collection area P to the destination area S. The shaft 2b is rigid. In fact, the casing 2c can house only one longitudinal section of the helix 2a, while another longitudinal section of the helix 2a protrudes outside the casing 2c. As an alternative to the above or in addition to the above, the casing 2c can enclose the helix 2a only around the longitudinal axis Z for a predetermined angle, leaving the helix 2a uncovered for the remaining angle.

[0059] In the example shown, the casing 2c has a tubular shape, thus defining a radially closed channel inside which at least a portion of the length of the helix 2a is housed. The casing 2c is therefore delimited by an inner surface 2e, which in the example shown is cylindrical. In alternative embodiments not shown, the casing 2c can have a "U" shaped cross section, i.e. open on one side.

[0060] The spiral 2a has a first end 20, suitable to be positioned in the destination area "S", and a second end 21, opposite the first end 20, suitable to be positioned in the collection area "P". A motor 5, which can be positioned close to the destination area "S" of the device 1, allows the spiral 2a to rotate around the longitudinal axis Z. The motor 5 can be connected to the first end 20 of the spiral 2a.

[0061] In the example shown, the destination area "S" is positioned at a higher level than the collection area "P". In this case, the longitudinal axis Z of the shaft 2b is inclined with respect to the horizontal direction, that is, with respect to the ground. In other words, the first end 20 of the spiral 2a is positioned at a higher level than the second end 21. In this case, the device 1 is suitable to transport the fluid outside the tank 3 by lifting it towards the destination area "S".

[0062] The spiral 2a has a plurality of turns 2d. The spiral 2a can have a variable pitch, in which case the distance between the turns 2d varies along the longitudinal axis Z of the shaft 2b, or it can have a constant pitch, in which case the distance between two consecutive turns 2d remains constant along the longitudinal axis Z of the shaft 2b.

[0063] If the spiral 2a has a variable pitch, the pitch can increase from the collection area "P" to the destination area "S" (for example, as shown in the figure). Figure 2 There can be areas in the spiral 2a with different pitches, for example depending on the application for which the spiral 2a is designed to be applied.

[0064] In the example shown, the spiral 2a has a first portion with constant pitch inside the casing 2c and a second portion with constant pitch upstream of the casing 2c close to the collection area "P". The pitch of the first portion is greater than the pitch of the second portion.

[0065] The screw conveyor 2 is configured for transporting both the liquid and solid parts of the fluid contained in the tank 3 towards the separation plant. To this end, the spiral 2a is housed inside the casing 2c so that the respective head surfaces 2f of the turns 2d of the spiral 2a are in direct contact with the casing 2c. In this way, it is possible to limit the amount of liquid that can pass through the head surfaces 2f of the turns 2d and the casing 2c to return backwards to the collection area "P" to a negligible level (if the conveyor 2 is positioned so that the collection area "P" is arranged close to the lower area of the device 1, as shown in the figure).

[0066] In one embodiment, the spiral 2a and the casing 2c, which winds around the shaft 2b on which the spiral 2a is wound, contact each other over a predetermined angle.

[0067] The helix 2a can be in contact with the inner surface 2e of the housing 2c over an angle (range) of at least 180°.

[0068] In other words, the single head surface 2f of the turn 2d of the helix 2a is in contact with the inner surface 2e of the housing 2c at a predetermined contact angle, measured around the longitudinal axis Z of the shaft 2b. The contact angle can for example be 180°.

[0069] Thereby, the amount of fluid that returns (to the collection area “P”) through the head surface 2f of the turn 2d and the inner surface 2e can be minimized.

[0070] To this end, the helix 2a is in contact with the inner surface 2e of the housing 2c in an effective transport area, in which the transported fluid is collected, when the helix 2a is rotating.

[0071] In fact, when the helix 2a is rotating around the longitudinal axis Z of the shaft 2b, the transported fluid is not uniformly distributed over an angle of 360° around the longitudinal axis Z of the shaft 2b, but is collected in an effective transport area having a predetermined angular extension around the longitudinal axis Z.

[0072] In the shown example, as already explained, where the housing 2c has a tubular shape, the head surface 2f of the turn 2d faces the inner surface 2e of the housing 2c over an angle of 360° around the longitudinal axis Z.

[0073] Furthermore, as Figures 4A to 4C more clearly shown in

[0074] Other geometrical shapes of the head surface 2f are in principle possible.

[0075] The device 1 further comprises a support structure 60 for supporting the housing 2c, which can be seen more clearly in Figure 2 The support structure 60 can be arranged to support the housing 2c only on the side of the helical conveyor 2 facing the tank 3.

[0076] The support structure 60 can comprise support elements 6 shaped for example like flat plates and can extend parallel to the longitudinal axis Z.

[0077] The support elements 6 can be made of a metallic material.

[0078] The housing 2c can be supported by the support elements 6, for example on the non-load bearing side of the helix 2a, i.e. on the side of the helix 2a opposite the effective transport area, in which the fluid is collected while the fluid is transported towards the destination area “S”.

[0079] In the example shown, the support elements 6 are positioned in the central section and in the final section of the screw conveyor 2. The initial section of the screw conveyor 2 is in fluid communication with the collection area "P" (i.e. with the tank 3) to act as an inlet for the fluid containing the solid particles "PS". No support elements 6 are present in the initial section.

[0080] In one embodiment, the distance between the screw 2a and the inner surface 2e of the housing 2c can be adjustable. Thereby, the housing 2c can be moved towards the screw 2a such that the inner surface 2e of the housing 2c comes into contact with the head surface 2f of the screw 2a.

[0081] To adjust the distance between the screw 2a and the inner surface 2e of the housing 2c, the first end 20 (i.e. the upper end) of the screw 2a can be moved closer.

[0082] In the example shown, the second end 21 (i.e. the lower end) of the screw 2a is free to rest against the support structure 60 due to the action of gravity. More specifically, the second end 21 of the screw 20 rests against the end element 6c of the support structure 60.

[0083] The first end 20 of the screw 2a is constrained in a fixed position, for example connected to the motor 5.

[0084] The support elements 6 supporting the housing 2c are positioned at an adjustable distance from the housing 2c and close to the first end 20. By adjusting the distance of the housing 2c from the support elements 6, it is possible to adjust the distance of the housing 2c from the screw 2a to ensure that the head surface 2f of the turns 2d is in contact with the inner surface 2e of the housing 2c at least in the active transport area where the fluid is present during transport. This adjustment can be made before the device 1 starts operating (i.e. at the time of installation of the device 1) or, after the device 1 has been installed, during subsequent maintenance operations in order to correctly reposition the housing 2c even after the housing 2c and / or the screw 2a have undergone wear.

[0085] The housing 2c is therefore positioned with respect to the screw 2a without the housing 2c being preloaded against the screw 2a. For example, the support structure 60 can comprise end supports 6b shaped, for example, like plates, arranged to support the housing 2c close to the first end 20 of the screw 2a. The end supports 6b can be fixed to the support elements 6 by means of at least one fastening element, for example by means of screws. These screws, which are screwed to the support elements 6, can pass through respective slots formed in the end supports 6b, so that it is possible to adjust the position of the end supports 6b and of the housing fixed thereto.

[0086] Therefore, the above-mentioned slots allow adjusting the position of the helix 2a in such a way that the gap between the portion of the helix 2a transporting the fluid (in the active transport zone) and the inner surface 2e of the casing 2c is substantially zero.

[0087] The end support 6b can be made of a metallic material.

[0088] In the screw conveyor 2, a plurality of compartments can be defined, each compartment being defined between two consecutive turns 2d of the helix 2a, a portion of the inner surface 2e of the casing 2c and the shaft 2b. More specifically, Figure 3 Reference numbers are shown in relation to two pairs of adjacent compartments, one compartment being indicated with VI and the other compartment being indicated with V2. The other compartment V2 is adjacent to the compartment VI, in particular, with respect to the direction of transport D of the fluid along the screw conveyor 2, the other compartment is located before the compartment VI.

[0089] The casing 2c is made of a deformable polymeric material, whereby, when a solid particle "PS" (for example an aggregate) transported by the transport device 1 is positioned to interfere between the head surface 2f of at least one turn 2d of the helix 2a and the inner surface 2e of the casing 2c, the casing 2c is allowed to locally reversibly deform radially towards its outer portion.

[0090] In other words, when the solid particle "PS" is located between the head surface 2f of the turn 2d and the inner surface 2e of the casing 2c, the casing 2c locally (i.e. in the area where the solid particle "PS" is present) deforms in a substantially radial direction and towards the outside. This allows the solid particle "PS" to pass between the head surface 2d and the inner surface 2e, thereby moving from one compartment VI from which the solid particle "PS" comes to another compartment V2 adjacent to the compartment VI. More specifically, the other compartment V2 is located before the compartment VI with respect to the direction of transport D.

[0091] For example, the deformable polymeric material with which the casing 2c is made is polyurethane. Therefore, if a solid particle is jammed between the head surface 2f of the turn 2d of the helix 2a and the inner surface 2e of the casing 2c, the casing deforms radially and allows the passage of the solid particle "PS". The solid particle "PS" is thereby moved from the compartment VI to the other compartment V2 and is thus moved away from the outer surface 2e of the casing 2c. Thereby, the solid particle "PS" is returned to a position closer to the shaft 2b, where it can be correctly transported by the helix 2a.

[0092] After the solid particle "PS" has been transferred to the other compartment V2, the casing 2c returns to its initial configuration without permanent deformation.

[0093] Alternatively, the deformable polymeric material from which the shell 2c is made can be another reversibly compliant plastic material having characteristics similar to those of polyurethane, such as, for example, polyethylene.

[0094] Thanks to the reversible radial deformability, the shell 2c obtained (i.e., the screw conveyor 2) can have no significant permanent deformations, the shell 2c has greater durability, and the shell 2c is less subject to wear caused by the solid particles.

[0095] In the example shown, the helix 2a is also made of deformable polymeric material, which can be the same material as that from which the shell 2c is made, or a different material from that of the shell 2c. More specifically, the helix 2a can be made of polyurethane, or of another deformable polymeric material, such as, for example, polyethylene.

[0096] More in detail, the turns 2d are entirely made of deformable polymeric material. On the other hand, the shaft 2b is made of a metallic material, in order to give the screw conveyor 2 sufficient torsional stiffness.

[0097] In this way, when the solid particles “PS” transported by the device 1 are interposed between the turns 2d and the inner surface 2e of the shell 2c, the helix 2a (or, more precisely, the respective turns 2d) can reversibly deform. In particular, the turns 2d can bend backwards with respect to the transport direction D.

[0098] In this way, if a solid element is jammed between the head surface 2f of the turns 2d of the helix 2a and the inner surface 2e of the shell 2c, the turns 2d bend, and since the shell 2c deforms simultaneously, the particles “PS” are allowed to pass from the compartment VI to the other compartment V2.

[0099] Figures 4A to 4C The passage of the solid particles “PS” from one compartment VI to the other compartment V2 is schematically shown. More specifically, Figure 4A The solid particles “PS” are shown in the compartment VI and jammed between the head surface 2f of the turns 2d and the inner surface 2e. Figure 4B The shell 2c is shown locally deformed towards the outside, while the turns 2d bend. This allows the solid particles “PS” to pass from the compartment VI to the other compartment V2 in front, as Figure 4C shown.

[0100] When the turns 2d return to the undeformed configuration, they exert a thrusting force on the solid particles “PS”, which pushes the solid particles “PS” towards the shaft 2b, as shown by the arrow F in Figure 4C This prevents the solid particles “PS” from jamming again between the shell 2c and the helix 2a.

[0101] When the turns 2d are made entirely of elastically deformable material, the propulsion force exerted by the turns 2d is generated in a particularly effective manner. If the turns 2d are made of a compliant material only close to the head surface 2f, the turns 2d will be more difficult to bend to project the solid particles "PS" towards the shaft 2b.

[0102] The deformation of the helix 2a can occur simultaneously with the deformation of the shell 2c. Thus, two deformations occur simultaneously in opposite directions, namely the turns 2d are deformed in a bending manner towards the shaft 2b, while the shell 2c is deformed in a widening manner away from the shaft 2b. These two deformations act in synergy to project the solid particles "PS" towards the longitudinal axis Z in a particularly effective manner.

[0103] The deformation is limited only in the area through which the solid particles "PS" pass. In the remaining areas, the helix 2a and the shell 2c continue to transport the fluid without deforming.

[0104] It can happen that, when the machine for recycling the concrete components is stopped, the concrete in the device 1 deposits on the surface of the helix 2a and hardens.

[0105] In this case, when the screw conveyor 2 is restarted, the deformation of the shell 2c and / or of the helix 2a makes it possible for the concrete fragments that remain attached to the screw conveyor 2 to be quickly detached from the shell 2c and / or from the helix 2a. These fragments can be transported to the destination area "S" to be recycled.

[0106] The support structure 60 can also comprise an intermediate support flange 6d arranged to support the shell 6c in an intermediate area thereof, in particular in the area of the passage between the loading portion 23 of the screw conveyor 2 and the transport portion 24 of the screw conveyor. In the loading portion 23, the screw conveyor 2 receives the fluid from the tank 3, while in the transport portion 24, the screw conveyor 2 transports the fluid out of the tank 3.

[0107] The shell 2c is free to deform radially outwards at least over a substantial portion of its length along the axis Z. For example, the outer shell 2c is free to deform radially outwards along more than half of its length along the axis Z. Precisely, the outer shell is free to deform radially outwards in the portion of the outer shell where the support structure 60 is not present.

[0108] More specifically, the outer shell is free to deform radially outwards in the effective transport area, in which the flowable material to be transported is gathered during transport. The effective transport area can be opposite the support element 6 of the support structure 60, i.e. positioned diametrically opposite the support element 6 with respect to the axis Z.

[0109] It should be noted that the shell 2c is devoid of ribs or reinforcing elements in the area thereof opposite the support element 6, i.e. in the active transport area of the fluid during transport. This avoids the presence of portions with different compliances in the active transport area, which could have a negative impact on the operation of the screw conveyor 2.

[0110] Advantageously, the device 1 as described above allows to transport solid materials with variable granulometry, with or without the presence of a liquid, or to transport only a liquid if there are no longer solid materials to be transported or if the system to which the transport device 1 is installed normally transports a liquid, but which can present accidental solid elements.

[0111] Furthermore, thanks to the deformability of the shell 2c, it is possible to install in the device 1 a motor 5 with reduced power compared to the motors used in the devices of the prior art, which allows to reduce the energy consumption and therefore to save energy in the working time.

[0112] It should be noted that if the deformable polymeric material is polyurethane, the adhesion of the concrete to this material is poor, since polyurethane is a highly apolar material with anti-adhesion properties.

[0113] Furthermore, polyurethane is a flexible material and even if the concrete adheres to the inner surface 2e or to the helix 2a, the deposits of concrete remain on the compliant surface, which when the machine is restarted causes the deposits to break apart and therefore to be expelled.

[0114] The present application further relates to a method for transporting concrete residues. The method comprises the step of providing a transport device 1 such as the one described above (according to one or more embodiments).

[0115] The method therefore comprises filling the collection area "P" with a fluid such as a liquid (for example, water) in which solid portions (for example, aggregates "I", i.e. concrete residues) are dispersed.

[0116] At this point, the method comprises transporting the fluid from the collection area "P" to the separation plant 4 (i.e. to the destination area "S") by using the device 1 described above.

[0117] If during the transport step, solid particles "PS" are interposed between the head surface 2f of at least one turn 2d of the helix 2a and the inner surface 2e of the shell 2c, the method comprises the step of reversibly radially deforming the shell 2c of the device 1 (i.e. of the screw conveyor 2) as Figure 4B schematically shown. From this, it is possible to transfer the solid particles "PS" from a compartment VI (defined between two turns 2d and the shell 2c) Figure 4A ) to another compartment V2, which is located before the compartment VI with respect to the transport direction D of the fluid transported by the screw conveyor 2. Figure 4C ​

[0118] If, during the transport step, the aggregate is interposed between the head surface 2f of at least one turn 2d of the screw 2a and the inner surface 2e of the casing 2c in an interfering manner, the method can further comprise a step of reversibly deforming the screw 2a of the device 1 (as schematically shown in Figure 4B

[0119] The step of reversibly deforming the screw 2a can occur simultaneously with the step of reversibly deforming the casing 2c.

[0120] The described method improves the efficiency of the transport. Moreover, the method allows to reduce the wear of the casing 2c of the conveyor 2 and / or to reduce the wear of the screw 2a.

[0121] The present invention also relates to a system for recovering and separating aggregates. The system comprises a tank 3 for containing a fluid, the fluid comprising a liquid in which aggregates to be recovered are dispersed, and the system comprises a transport device 1 such as described above (according to one or more of the described embodiments). The screw conveyor 2 of the device 1 is configured for collecting the fluid from a collection area "P" defined by the tank 3 (for example positioned on one side of the tank 3) and for transporting the liquid and the aggregates to be recovered from an upstream portion to a downstream portion of the screw conveyor 2. The fluid transported by the screw conveyor 2 towards the destination area "S" has substantially the same composition as the fluid present in the tank 3, since the screw conveyor 2 allows to transport both the solid portion and the liquid portion of the fluid without the majority of the liquid portion backflowing. The tank 3 can be made of a metallic material, in particular sheet metal.

[0122] The tank 3 houses an auxiliary screw conveyor 22 adapted to move the fluid by causing it to flow out of the tank 3 through a discharge area 3a.

[0123] Preferably, the tank 3 is equipped with a filter grid, not shown, near which a truck mixer or an operator can introduce the fluid in which the aggregates are dispersed. In other words, the tank 3 defines an inlet portion for introducing the concrete into the system.

[0124] The transport device 1 is positioned transversely with respect to the tank 3. In other words, the discharge area 3a is positioned in a transverse portion of the tank 3 and the device 1 is in fluid communication with the tank 3 (i.e. with the collection area "P") through the discharge area 3a to introduce the flow into the screw conveyor 2.

[0125] ​The auxiliary screw conveyor 22 is positioned in the tank in such a way as to be connected or connectable to the upstream portion of the screw conveyor 2, defining an "L" shape. In other words, the auxiliary screw conveyor 22 is substantially perpendicular to the screw conveyor 2 of the transport device, and the auxiliary screw conveyor is connected or connectable to the screw conveyor 2 by suitable mechanical means near the discharge area 3a.

[0126] Furthermore, the tank 3 acts as a buffer in which the concrete residues from the truck mixers can be stored, which can be discharged into the tank 3 at the maximum permitted discharge speed, without the operator having to worry about how much material has actually been processed. This makes it possible to speed up the unloading operations of the truck mixers.

[0127] The system also comprises a separation device configured to separate the aggregates from the fluid containing the concrete residues.

[0128] The separation device is positioned downstream of the transport device 1, at the destination area "S".

[0129] The separation device is configured to act on the fluid transported by the transport device 1, separating from the fluid the larger aggregates (for example, gravel), the smaller aggregates (for example, sand) and the water which can then be reused.

[0130] The present application makes it possible to overcome the drawbacks of the prior art.

[0131] More specifically, the present application allows to reduce or prevent the deformation of the casing 2c and / or of the screw 2a, reducing or preventing wear. Furthermore, the present application allows to reduce the installation power. The present application also makes it possible to reduce the overall noise level of the system during the working time.

[0132] In summary, the present application allows to transport elements with non-uniform grain size and any liquid present, without clogging and blocking the elements between the screw 2a and the casing 2c, preventing permanent deformation and rapid wear of the screw 2a and of the casing 2c.

Claims

1. A transport device for conveying a flowable material, the device (1) comprising a screw conveyor (2) for collecting the flowable material from a collection area (P) and transporting the flowable material toward a destination area (S), and a straight shaft (2b) extending along a longitudinal axis (Z) from the collection area (P) to the destination area (S), the screw conveyor (2) comprising a screw (2a) and a housing (2c), the screw being wound on the shaft (2b), the housing at least partially accommodating the screw (2a), the screw (2a) having a plurality of turns (2d), the housing (2c) having an inner surface (2e) facing a corresponding head surface (2f) of at least some of the plurality of turns (2d), defining a compartment (V1, V2) between two consecutive turns of the plurality of turns (2d) and the housing (2c), characterized in that, The outer shell (2c) is at least partially made of a deformable polymeric material such that when solid particles (PS) of the flowable material conveyed by the auger (2a) are between the head surface (2f) of one of the plurality of turns (2d) and the inner surface (2e) of the outer shell (2c), the outer shell (2c) deforms radially and reversibly outward to allow the solid particles (PS) to pass between the head surface (2f) of the turn (2d) and the inner surface (2e) of the outer shell (2c) to transfer from one compartment (V1) to another compartment (V2) adjacent to the compartment (V1), and wherein the turns of the plurality of turns (2d) are made of a deformable polymeric material so as to be reversibly bent when the solid particles (PS) conveyed by the auger (2a) are between the head surface (2f) of one of the plurality of turns and the inner surface (2e) of the outer shell (2c).

2. The transport device according to claim 1, wherein, The outer shell (2c) can deform freely radially outward, at least in the effective transport area where the flowable material (V) accumulates during transport.

3. The transport device according to claim 1, wherein, The outer shell (2c) does not have ribs or reinforcing elements.

4. The transport device according to claim 1, wherein, The deformable polymeric material that at least partially forms the outer shell (2c) is polyurethane.

5. The transport device according to claim 1, wherein, The deformable polymeric material used to make the turns in the plurality of turns (2d) is polyurethane.

6. The transport device according to claim 1, wherein, The shaft (2b) is made of metal.

7. The transport device according to claim 1, wherein, The outer shell (2c) has a tubular shape to define a radially closed channel comprising at least a portion of the length of the helical element (2a).

8. The transport device according to claim 1, the transport device further comprising a support structure (60) for supporting the outer shell (2c), the support structure (60) comprising a support element (6) extending parallel to the longitudinal axis (Z) along one side of the outer shell (2c).

9. The transport device according to claim 8, wherein, The outer shell (2c) is free to deform radially outward at least in the effective transport area where the flowable material (V) accumulates during transport, and wherein the effective transport area is located in the portion of the outer shell (2c) opposite to the support element (6).

10. The transport device according to claim 8, wherein, The shaft (2b) has a first end that is arranged in a fixed position and connected to the motor (5), and a second end that is opposite to the first end and abuts against the support structure (60).

11. The transport device according to claim 8, wherein, The outer shell (2c) is positioned at an adjustable distance from the support element (6) to adjust the position of the outer shell (2c) relative to the screw (2a) such that the inner surface (2e) of the outer shell (2c) can contact the head surface (2f) of at least some of the plurality of turns (2d).

12. The transport device according to claim 11, the transport device further comprising at least one fastening element for fastening the outer shell (2c) relative to the support element (6) in a fixed position after adjusting the distance between the support element (6) and the outer shell (2c).

13. The transport device according to claim 1, wherein, The longitudinal axis (Z) is tilted such that the destination area (S) is positioned at a higher height than the collection area (P).

14. The transport device according to claim 1, wherein, The helical component (2a) includes a first portion located inside the outer casing (2c) and having a constant pitch, and the helical component (2a) also includes a second portion upstream of the first portion and having a constant pitch, the pitch of the first portion being greater than the pitch of the second portion.

15. A method for conveying a flowable material, comprising the following steps: - Introduce the flowable material into the collection area (P); - A transport device (1) is provided, comprising a screw conveyor (2), the screw conveyor (2) comprising a screw (2a) and a housing (2c), the screw being wound on a shaft (2b) extending along a longitudinal axis (Z), the housing at least partially accommodating the screw (2a), the screw (2a) having a plurality of turns (2d), the housing (2c) having an inner surface (2e) facing a corresponding head surface (2f) of at least some of the plurality of turns (2d), defining a compartment (V1, V2) between two consecutive turns of the plurality of turns (2d) and the housing (2c), the housing (2c) being at least partially made of a deformable polymeric material; - The flowable material is transported from the collection area (P) to the destination area (S) by using the transport device (1); During the transport step, when the solid particles (PS) of the flowable material conveyed by the auger (2a) are between the head surface (2f) of one of the multiple turns (2d) and the inner surface (2e) of the outer shell (2c), the outer shell (2c) deforms radially and reversibly outward, such that the solid particles (PS) pass between the head surface (2f) of the turn (2d) and the inner surface (2e) of the outer shell (2c) to transfer from one compartment (V1) to another compartment (V2) adjacent to the compartment (V1); and - During the transport step, when the solid particles (PS) conveyed by the auger (2a) are between the head surface of at least one of the plurality of turns (2d) and the inner surface (2e) of the outer casing (2c), the at least one turn is reversibly deformed.

16. The method according to claim 15, wherein, When the solid particles (PS) are transferred from the compartment (V1) to the other compartment (V2), the outer shell (2c) is restored to its undeformed configuration, thereby causing the solid particles (PS) to project toward the longitudinal axis (Z).

17. The method according to claim 15, wherein, During the step of reversibly deforming at least one of the plurality of turns (2d), the at least one turn bends and then returns to its undeformed configuration, thereby causing the solid particles (PS) to project toward the axis (2b).

18. A system for recovering aggregate from a flowable material consisting of a fluid containing concrete residue, comprising a tank (3) for containing the fluid, wherein the aggregate to be recovered is dispersed in the fluid, and the system comprising a transport device (1) according to claim 1, wherein, The screw conveyor (2) is configured to collect the fluid from the tank (3) and transport the aggregate to be recycled and the liquid portion of the fluid from the upstream portion of the screw conveyor (2) to the downstream portion.

19. The system according to claim 18, wherein, The transport device (1) is laterally positioned relative to the tank (3), which includes an auxiliary screw conveyor (22) for conveying fluid toward the screw conveyor (2), the auxiliary screw conveyor (22) being positioned in the tank (3) and defined in an "L" shape together with the screw conveyor (2) of the transport device (1).

20. The system of claim 18, further comprising a separation device for separating the aggregate from the liquid portion of the fluid, the separation device being located downstream of the transport device (1).

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