Apparatus and method for identifying and separating solid waste containing asbestos from other solid particulates

Abstract

The present invention concerns an apparatus (100), a plant (200) and an identification and separation method for identifying asbestos-containing solid waste (MCA) in a plurality of solid particulates (M) and separating said asbestos-containing solid waste (MCA) from the remaining solid particulates of said plurality of solid particulates (M). In particular, the identification of asbestos-containing solid waste is based on signals generated by a first detection unit (2), comprising an infrared ray source (21) configured to emit an X-ray beam so as to strike the plurality of solid particulates (M) and an X-ray sensor (22) configured to receive and detect the X-rays emitted by the X-ray source (21), and by a second detection unit (3) which comprises a video camera (31) operating in the near infrared (NIR) band and arranged so as to acquire images of the plurality of solid particulates (M).

Description

TECHNICAL SECTOR

[0001] The present invention relates to an identification and separation apparatus and to an identification and separation method for identifying and separating asbestos-containing solid waste from other solid particulates, namely from asbestos-free solid particulates. The present invention relates moreover to an identification and separation plant which comprises the aforementioned identification and separation apparatus. In greater detail, the plurality of solid particulates subjected to separation comprises or consists of solid particulates originating from construction, demolition or reclamation sites, including so-called "backfill material".PRIOR ART

[0002] Commercially speaking the term "asbestos" is used to indicate certain fibrous silicate minerals of natural origin (chrysotile, crocidolite, amosite, tremolite, anthophyllite and actinolite).

[0003] The fibres of these silicate minerals may be woven together and easily bond with other substances, such as lime, gypsum, cement, rubber, plastic materials, allowing the production of various types of articles. For these reasons and owing to the relatively low cost and the high heat-resistance, abrasion resistance, wear resistance, corrosion resistance, acoustic absorption and thermal insulation properties, so-called asbestos was used on a massive scale in various industrial applications.

[0004] Over the years, one of the sectors where so-called asbestos has been most widely used is the building industry, in particular in combination with cement and known under the commercial name of "Eternit". For example, asbestos was used for the production of roofing, chimneys, insulating panels, partitions, water tanks, vinyl flooring, pipe insulation.

[0005] However, already at the beginning of the 1960s it was recognized that, following degradation / alteration and following activities involving the handling of articles containing asbestos, a number of asbestos fibres tend to be released into the air. The inhalation or ingestion of asbestos fibres may constitute a serious risk for human health. For this reason, over time the use of asbestos in many industrial sectors has been significantly reduced.

[0006] Nowadays, in particular in the building sector, it is not always known with certainty if and where an asbestos-containing article is present. Therefore, it cannot be known a priori whether waste material which has been produced, for example in a site demolition or reclamation activity, contains asbestos or not. Also soil with the presence of any anthropic materials (commonly known as "backfill material" or more simply "backfill") may contain asbestos.

[0007] In order to manage more safely the solid particulates and waste originating from construction, reclamation or demolition sites, at present in various countries, including Italy, all these solid waste particulates, including the backfill material, must be collected in suitable pallets or other containers (such as so-called "big bags") sealed with plastic material being disposed of in dangerous-waste disposal sites. In brief, therefore, solid particulates not containing asbestos must be sent to dangerous-waste disposal sites, together with the waste actually containing asbestos.

[0008] Firstly, this represents a significant wastage of resources since the solid particulates and waste originating from sites for construction, demolition or reclamation of buildings or infrastructures which do not contain asbestos, or at least part of it, could be reused. Such an approach underpins the idea of environmental sustainability.

[0009] Moreover, the disposal of a given amount of solid particulates in disposal sites for dangerous waste has a greater cost than the disposal of the same amount of solid particulates in disposal sites for waste which is not dangerous.

[0010] A further problem is that of said dangerous waste disposal is associated with the fact that the dangerous-waste disposal sites are few and far between within the territory.

[0011] For example, in Italy the few dangerous waste disposal sites are mainly in northern Italy and are not sufficient to fully satisfy the demands for disposal, forcing the potential service users to dispatch their dangerous waste to waste disposal sites abroad, at an exorbitant cost, with time needed for official certification of the waste and with the need to transport the dangerous waste thousands of kilometres.SUMMARY

[0012] The problem underlying the present disclosure is therefore that of reducing the quantity of solid particulates, in particular that originating from sites for the construction, demolition or reclamation of buildings or infrastructures, to be disposed of in the special dangerous-waste disposal sites.

[0013] The task of the present invention is therefore to identify, in a plurality of solid particulates, the asbestos-containing waste (below MCA) and separating this MCA waste from the remainder of the asbestos-free solid particulates of the same plurality of solid particulates.

[0014] Another task of the present disclosure is to proceed to identify and separate asbestos-containing waste while limiting the need for human intervention.

[0015] This task as well as these and other objects which will emerge more clearly below are achieved by an identification and separation apparatus for identifying and separating asbestos-containing solid waste from other solid particulates, by an identification and separation plant comprising said apparatus and by an identification and separation method for identifying asbestos-containing waste in a plurality of solid particulates and separating said asbestos-containing waste from the remaining solid particulates.

[0016] Further characteristic features and advantages of the present invention will emerge more clearly from the description of a preferred, but non-limiting embodiment, of a separation method and plant, illustrated by way of a non-limiting example in the figures of the attached drawings, in which: Figure 1 shows a schematic cross-sectioned view of an identification and separation apparatus according to the present invention; Figure 2 shows a side view of the identification and separation apparatus according to the invention and of the separation plant comprising it, along the cross-sectional line II-II of Figure 2A; Figure 2A shows a plan view of the identification and separation apparatus according to the invention and of the plant comprising it; Figure 3 shows a schematic exemplary view of the operating method according to the invention; Figure 4 shows a variation of embodiment of a part of the identification and separation apparatus according to the invention; Figure 5 shows an enlarged view of the portion of the identification and separation apparatus to the left of the line AA in Figure 2; Figure 6 shows an enlarged view of the portion of the identification and separation apparatus to the right of the line AA in Figure 2; Figure 7 shows an enlarged view of the portion of the identification and separation apparatus to the left of the line BB in Figure 2A; Figure 8 shows an enlarged view of the portion of the identification and separation apparatus to the right of the line BB in Figure 2A.

[0017] With reference to the attached figures, an embodiment of an identification and separation apparatus for identifying and separating asbestos-containing solid waste MCA, according to the present invention, is indicated by the reference number 100. In other words, the apparatus 100 according to the present invention is apt to identify asbestos-containing solid waste MCA in a plurality of solid particulates M and to separate said asbestos-containing solid waste MCA from the remaining asbestos-free solid particulates MNA of the plurality of solid particulates M.

[0018] In the context of the present disclosure, the expression "plurality of particulates" is understood as meaning an incoherent mixture of fragments, pieces or solid agglomerates.

[0019] In particular, the identification and separation apparatus 100 comprises a transport unit 1 configured to transport the solid particles M from a feeding zone ZA to a first operating zone Z1 and from the first operating zone Z1 to a second operating zone Z2.

[0020] The identification and separation apparatus 100 also comprises a first detection unit 2 and a second detection unit 3.

[0021] The group or assembly comprising the two units, i.e. first detection unit 2 and second detection unit 3, is called hereinbelow, for simpler description, optical selector.

[0022] The first detection unit 2 comprises in turn an infrared ray source 21 configured to emit an X-ray beam towards the first operating zone Z1 so as to strike the plurality of solid particulates M during use present in the first operating zone Z1, and an X-ray sensor 22 configured to receive and detect the X-rays emitted by the X-ray source 21. In particular, the X-ray source 22 is configured to receive and detect the X-rays emitted by the X-ray source 21 which, during use, have crossed the plurality of solids M present in the first operating zone 11. In other words, the X-ray sensor is configured to receive and detect the X-rays emitted by the X-ray source 21 in the first zone Z1. During use, therefore, these X-rays have crossed the solid particulates M present in the first operating zone Z1.

[0023] The second detection unit 3 comprises, in turn, a video camera 31 operating in the NIR (Near Infrared) band and arranged so as to focus on the second operating zone Z2 in order to acquire images of the plurality of solid particulates M during use present in the second operating zone Z2.

[0024] The presence of the video camera 31, operating in the near infrared band, hereinbelow called "NIR video camera" for simpler description, increases the capacity of the apparatus 100 to identify asbestos-containing solid waste MCA. In fact, the presence of asbestos in the solid particulates where the asbestos is embedded in a cement matrix might not be particularly evident.

[0025] In fact, cement and asbestos have a fairly similar spectrometry. For this reason, owing to the presence of the NIR video camera 31, operating in the near infrared band, it is possible to identify the presence, if superficial, of the asbestos present in the waste where this is not particularly or easily visible from the spectrometric analysis.

[0026] In addition, the presence of the NIR video camera 31 allows confirmation of the presence of asbestos in the solid particulates where this is already evident via the X-rays.

[0027] The identification and separation apparatus 100 also comprises a control unit 4, connected to the first detection unit 2 and to the second detection unit 3.

[0028] In particular, the control unit 4 is configured and / or programmed to process a signal, or image, generated by the first detection unit 2 and an image generated by the second detection unit 3 in order to identify asbestos-containing waste MCA in the plurality of solid particulates M.

[0029] In other words, the control unit 4 is configured and / or programmed to distinguish an asbestos-containing waste, or fragment or particulate, MCA from the other solid particulates which are not dangerous, indicated below and in Figure 1 by the abbreviation "MNA", in the plurality of solid particulates using the recordings performed by the first detection unit 2 and the second detection unit 3. In this way, the identification of the asbestos-containing waste MCA is performed automatically, owing to an optical instrument, without the need for the human intervention of an operator.

[0030] Therefore, a plurality of solid particulates M enter into the identification and separation apparatus 100 according to the present invention, and asbestos-containing waste MCA (materials containing asbestos), and non-dangerous solid particulates, i.e. asbestos-free solid particulates MNA (materials not containing asbestos), exit separated from each other.

[0031] The non-dangerous solid particulate may be classified as a by-product or as "end of waste" in the future, in keeping with the existing legislation.

[0032] An "end of waste" is understood as being that waste which, following a recovery activity, has ceased to be waste, being classified as secondary raw materials. The recovery activity may also consist simply in checking the waste in order to check whether it complies with the criteria laid down in Community laws or in the Decrees of the Ministry of the Environment of a given country, such as Italy.

[0033] In addition, the identification and separation apparatus 100 comprises separation means 5 which can be activated by the control unit 4. The separation means 5 are, for example, controlled by the control unit 4 so as to start functioning. The control unit 4, in other words, is configured to operate the separation means 5.

[0034] The separation means 5 are configured to separate, namely to displace or move, asbestos-containing waste MCA from the remaining non-dangerous particulates MNA of the plurality of solid particulates M. In this way, the separation of the asbestos-containing waste MCA also takes place automatically, owing to an optical instrument, without requiring the human intervention of an operator.

[0035] According to a preferred aspect, the separation means 5 are configured to displace the asbestos-containing waste MCA from the second operating zone Z2 to a waste zone ZS. Therefore, the asbestos-containing waste MCA is separated owing to the separation means 5 from the remaining solid particulates, namely the non-dangerous solid particulates MNA, of the plurality of solid particulates M and transferred into a different zone, i.e. said waste zone ZS.

[0036] In the context of the present invention, the term "waste" indicates any solid waste which the proprietor gets rid of, or has decided or is obliged, to get rid of.

[0037] Preferably, the solid particulates M entering the identification or separation apparatus 100 or plant 200, or on which the separation method according to the present invention has been performed, comprise or consist of an incoherent mixture of fragments or parts or agglomerates originating, i.e. derived from construction, demolition or reclamation activities. Said solid particulates may comprise, or consist of, one or more wastes distinguished by the following codes of the European List of Waste (EER) in force as from 18 October 2024: 17.05.03*, 17.06.05*, 17.09.03*, 19.13.01*, 17.05.04, 17.09.04, 19.13.02.

[0038] According to a preferred aspect of the present invention, the transport unit 1 comprises a conveyor belt 14.

[0039] More preferably, the transport unit 1 also comprises a frame with which the conveyor belt 14 is associated.

[0040] The conveyor belt 14 extends mainly along a main development axis X1 between a rear portion 141 and a front portion 142 and has an upper face 143 suitable for supporting and transporting the plurality of solid particulates M.

[0041] The rear portion 141 and the front portion 142 are defined as such with respect to the direction of advancing movement of the upper face 143 of the conveyor belt 14. The upper face 143, in fact, moves along a direction parallel to the main development axis X1 from the rear portion 141 towards the front portion 142 of the conveyor belt 14.

[0042] According to a preferred aspect of the present invention, the X-ray sensor 22 comprises or consists of a scanner with scintillator sensors which are arranged alongside each other over its width, namely are arranged alongside each other in a direction perpendicular to the main development axis X1 of the conveyor belt 14. In particular, the scintillator sensor scanner is arranged alongside the conveyor belt 14 in the first operating zone Z1.

[0043] Preferably, these scintillator sensors comprise a plurality of pixels. More preferably, each pixel has a size of 1.5 mm. The pixels are configured to acquire an image of the solid particulates M present in the first operating zone Z1. In particular, the scintillator sensors are configured to acquire, by means of the pixels, an image of the X-rays absorbed by the solid particulates M during use in the first operating zone Z1.

[0044] According to a preferred aspect, from this image and knowing the speed of advancing movement of the conveyor belt 14, the control unit 4 is configured to calculate the position of each fragment, namely of each solid particulate, of the plurality of solid particulates M.

[0045] In particular, from this image and knowing the speed of advancing movement of the conveyor belt, the control unit 4 is configured to calculate the position of each asbestos-containing waste MCA. In other words, the pixels reconstruct the image of the solid particulates M which pass on the conveyor belt 14 opposite the scanner 22; therefore the image is located on the conveyor belt by the X-ray sensor scanner 22; the control unit 4 knows where each asbestos-containing waste MCA is located with respect to the conveyor belt 14 and activates the separations means 5 so that they deal with the solid particulate detected as being asbestos-containing MCA.

[0046] The NIR video camera 31 has, by way of example, a sensor with an array of 320 (spectral) x 256 (spatial) pixels.

[0047] By means of the (optical) lens the NIR video camera 31 manages to cover the width of the belt 14, namely a dimension of the conveyor belt perpendicular to the main development axis X1, spreading, i.e. distributing the spatial pixels over the width of the belt 14, thus reconstructing the image of the fragment, namely of each particulate, and its position on the conveyor belt 14. Here also, after receiving the image with its position and classifying the object, the control unit 4 emits a command to the separation means 5.

[0048] The NIRS (N.I.R.S. Near Infrared Reflectance Spectroscopy) technique is an analysis method which makes use of certain physical properties of the material, in particular the interaction of the latter with the near infrared rays.

[0049] This technique makes use of the specific capacity of each chemical compound to absorb, transmit or reflect the light rays. The combination of the absorbing properties, together with the dispersion properties of the light energy, results in diffused reflectance of the light, which provides information about the chemical composition of the sample. The time taken for a single analysis varies from a few seconds to a few minutes.

[0050] The spectral differences allow classification of the fragments, i.e. of the solid particulates of different material; in order to identify, among these, the asbestos-containing waste MCA, with consequent activation of the separation means 5, which are described more fully below, for elimination or separation of the said asbestos-containing fragments MCA, namely the asbestos-containing waste MCA, from the remaining asbestos-free solid particulates MNA of said plurality of solid particulates M, namely from the stream of material in transit on the transport unit 1.

[0051] By way of example and preferably, the control unit 4 is configured to identify and distinguish between: fragments of asbestos with a smooth surface; fragments of asbestos rendered inert with an encapsulating agent; asbestos fragments with a rough "mesh" surface; fragments of fibre cement, rocks, stones, glass.

[0052] The fragments of asbestos with a smooth surface, the fragments of asbestos rendered inert with an encapsulating agent and the fragments of asbestos with a rough "mesh" surface are identified as MCA waste by the control unit 4.

[0053] The optical sensor is provided with a monitor which displays all the elements in transit in the stream of material on the conveyor belt 14, classified as MCA waste by the NIR / X-ray system, with consequent activation of the separation means 5, for example with activation of compressed-air blowing nozzles 5. In the case where some asbestos-containing waste MCA passes through without being identified, the following operations are performed: a check as to the cleanliness of the X-ray sensor 22, in particular of the scanner and the NIR video camera 31; calibration of the "whiteness" both of the X-ray sensor, in particular the scanner, and of the NIR telecamera.

[0054] Whiteness calibration is an operation, of the type known per se, which consists in restoring to the NIR video camera 31 and the X-ray sensor 22, in particular of the scanner, the maximum intensity reference level of the reflected or transmitted radiation, which reference level influences the classification of the objects and, over time, may change following soiling of and / or changing of the illumination. This operation is performed using a specific software by specialized operators under the instruction of the technicians of the machine construction company.

[0055] Figure 3 shows, by way of example, an image recorded by the NIR video camera 31 and / or by the X-ray sensor 22; the top part of Figure 3 shows the image transmitted by the NIR video camera 31 and / or by the X-ray sensor 22 to the control unit 4, where the parts or waste have a light colour, while the bottom part of Figure 3 shows the same image transmitted by the NIR video camera 31 and / or by the X-ray sensor 22, but in which the parts with asbestos are shown with a darker colour because they are classified by the control unit 4 as being "asbestos-containing material" MCA.

[0056] The conversion of the image recorded by the NIR video camera 31 and / or the X-ray sensor 22 into a classified image, namely where the asbestos-containing waste MCA is shown with a colour darker than that of the asbestos-free solid particulates MNA, is performed by the control unit 4. In other words, the control unit 4 is configured and / or programmed to receive from the X-ray sensor 22 and from the NIR video camera 31 an image of the solid particulates M present in the first operating zone Z1 and to detect in this image the asbestos-containing waste MCA.

[0057] In general, in the X-ray detection systems, the energy of the X-rays is converted directly into an electric signal which can be digitalized into a digital X-ray image. The digital image shows a shade of greyness, depending on the power with which the radiation reaches the X-ray sensors 22, once it has passed through the body.

[0058] In particular, the control unit 4 is configured or programmed to carry out or perform said identification or distinction by comparing the energy transmitted to the X-ray sensor 22 by the pieces of asbestos, namely the asbestos-containing waste MCA, with the energy transmitted by other asbestos-free materials MNA, for example rocks and fibre cement. Preferably, the control unit 4 is provided with classification software for performing said distinction or identification.

[0059] On a scale of 0 (not crossed, opaque) to 1 (transparent), asbestos is located midway compared to rocks (opaque, dense) and fibre cement.

[0060] According to a preferred aspect of the present invention, the feeding zone ZA corresponds to a zone opposite, or space opposite, the upper face 143 of the conveyor belt 14 along the rear portion 141. Similarly, the second operating zone Z2 corresponds to a zone opposite, or space opposite, the upper face 143 of the conveyor belt 14 along the front portion 142, and the first operating zone Z1 corresponds to a zone opposite, or space opposite, the upper face 143 of the conveyor belt 14 and situated in between the second operating zone Z2 and the feeding zone ZA.

[0061] According to a preferred aspect of the present invention, the transport unit 1 is configured to transfer the non-dangerous solid particulates MNA, namely the solid particulates not identified by the control unit 4 as being asbestos-containing waste MCA, into a delivery zone ZC.

[0062] According to a preferred aspect of the present invention, the conveyor belt 14 is apt to move the plurality of solid particulates M from the feeding zone ZA to the second operating zone Z2 along a direction of advancing movement parallel to the main development axis X1. Preferably, the speed of advancing movement of the conveyor belt 14 is predefined and known to the control unit 4. More preferably, the speed of advancing movement is such that the non-dangerous solid particulates MNA, which are not identified by the control unit 4 as asbestos-containing waste, have a kinetic energy such that, once the free edge of the front portion 142 is reached, they remain suspended in the air until they reach the delivery zone ZC (zone for collecting asbestos-free materials MNA).

[0063] More preferably, the speed of advancing movement of the upper face 143 of the conveyor belt 14 is between 3 m / s and 5 m / s, even more preferably the speed of advancing movement is about 4 m / s.

[0064] According to a preferred aspect of the present invention, the waste zone ZS is adjacent to second operating zone Z2. More preferably the delivery zone ZC is adjacent to the waste zone ZS.

[0065] According to a preferred aspect of the present invention, the identification and separation apparatus 100 comprises a partition element 9 suitable for dividing the waste zone ZS from the delivery zone ZC,

[0066] The delivery zone ZC is located at a greater distance from the front portion 142 of the conveyor belt 14 than the waste zone ZS, which is closer to the said front portion 142.

[0067] The partition element 9 extends upwards, namely substantially perpendicular to the main development axis X1 of the conveyor belt 14, in an intermediate zone between the waste zone ZS and the delivery zone ZC.

[0068] According to a preferred, but non-exclusive aspect, of the present invention, the separation means 5 comprise a plurality of blowing nozzles 51 arranged alongside each other in the vicinity of the second operating zone Z2. These blowing nozzles 51 are configured to emit a jet of pressurized fluid directed towards the asbestos-containing waste MCA, during use present in the second operating zone.

[0069] In other words, each of said blowing nozzles 51 is configured to emit a jet of fluid, preferably air, having a trajectory apt to strike the asbestos-containing waste MCA, present in the second operating zone Z2.

[0070] Preferably, said trajectory is transverse to the main development axis X1 of the conveyor belt 14. The jet of pressurized fluid is thus able to remove the asbestos-containing waste MCA from the second operating zone Z2 and displace it into the waste zone ZS.

[0071] According to a preferred aspect of the present invention, the blowing nozzles 51 are supplied by means of a duct connected to a pressurized fluid tank (not shown).

[0072] According to a preferred aspect of the present invention, the pressurized fluid is pressurized air or water.

[0073] According to a preferred aspect of the present invention, the separation means 5 comprise a plurality of blowing nozzles 51 arranged in series along an axis which is substantially horizontal and perpendicular to the main development axis X1.

[0074] Said blowing nozzles 51 are positioned opposite or in the vicinity of the end of the front portion 142 of the conveyor belt 14 and are directed or oriented so as to generate a jet of fluid towards the conveyor belt 14, in particular towards the upper face 143 of the conveyor belt 14. In other words, the blowing nozzles 51 are directed or oriented downwards. According to this preferred aspect, the control unit 4 is configured and / or programmed to actuate one or more specific blowing nozzles 51 of the plurality of nozzles 50 in order to generate a jet of fluid having a trajectory apt to strike asbestos-containing waste MCA, the latter having been identified by the optical selector in the first operating zone Z1, or in the second operating zone Z2, or in both zones.

[0075] Each blowing nozzle 51 comprises a compressed-air valve connected to a compressed-air duct. The blowing nozzles 51 are advantageously connected to the same compressed-air duct.

[0076] In other words, each blowing nozzle 51 of the plurality of nozzles is configured to emit a jet of fluid having a trajectory apt to strike the asbestos-containing waste MCA. Preferably, said trajectory is transverse to the main development axis X1 of the conveyor belt 14. The jet of pressurized fluid is thus able to remove the asbestos-containing waste MCA from the second operating zone Z2 and displace it into the waste zone ZS.

[0077] According to a preferred aspect of the present invention, each blowing nozzle 51 of the plurality of nozzles 50 is supplied by means of a duct connected to a pressurized fluid tank (not shown).

[0078] As mentioned above, also with reference to the plurality of blowing nozzles 51, the pressurized fluid is preferably pressurized air or pressurized water.

[0079] In an alternative variant of the present invention, not shown for simpler description, each blowing nozzle 51 of the plurality of nozzles 50 is a directable nozzle. In other words, the control unit 4 is configured and / or programmed to orient angularly each blowing nozzle 51 of the plurality of nozzles 50 with respect to the main development axis X1 of the conveyor belt 14. Expressed differently, the control unit 4 is configured to actuate each nozzle of the plurality of nozzles 41 so as to rotate along an axis of rotation perpendicular to the main development axis X1 of the conveyor belt 14.

[0080] As mentioned above, also with reference to the plurality of blowing nozzles, preferably each blowing nozzle 51 may be oriented or moved by means of a pneumatic cylinder or a mechanical drive. The orientation or movement of each blowing nozzle 51 is obtained in a manner known per se and therefore will not be further described.

[0081] According to a preferred aspect, the plurality of blowing nozzles 51 is associated with the frame of the transport unit 1.

[0082] The operating mode of the separation means 5 is as follows: when the optical selector detects a fragment or a particulate with asbestos, i.e. an MCA waste, the control unit 4, which is connected to the optical sensor, activates operation of those nozzles which are useful for blowing air against the identified asbestos-containing fragment or particulate MCA (forming therefore MCA waste), when this asbestos-containing fragment or particulate MCA has left the conveyor belt 14; being oriented downwards, the blowing nozzles 51 cause the deviation of the asbestos-containing fragment downwards, i.e. towards the underlying waste zone ZS.

[0083] The asbestos-free fragments MNA, or solid particulates without asbestos MNA, which are also launched by the conveyor belt 14 together with the asbestos-containing waste MCA, namely the fragments or particulates containing asbestos, are not intercepted by the compressed air flow emitted by the blowing nozzle 51 and proceed as a result of inertia beyond the waste zone ZS and are collected in the delivery zone ZC.

[0084] A variant of the separation means 5 is schematically shown in Figure 4.

[0085] In said variation of embodiment, the separation means 5 comprise a plurality of blowing nozzles 51 positioned at the end of the front portion 142 of the conveyor belt 14 and substantially underneath said end.

[0086] The blowing nozzles 151 are therefore positioned and configured to blow from below upwards so as to prolong the downward trajectory of the fragments, i.e. of the solid particulates M which are ejected from the conveyor belt 14.

[0087] In one or more further constructional variants of the invention, not shown, the separation means are of the solid thruster type, such as bars or levers or intercepting teeth, which are operated forwards and backwards into a rest position by electromechanical actuators and are configured to intercept the asbestos-containing waste MCA.

[0088] According to a preferred aspect of the present invention, the second detection unit 3 comprises illumination means 32 configured and positioned to generate a visible light beam towards the second operating zone Z2. In other words, the illumination means 32 are configured and positioned to emit a visible light beam in the direction of the second operating zone Z2, in order to illuminate the plurality of solid particulates M which, during the use according to the invention, is present in the second operating zone Z2.

[0089] For example, the illumination means 32 may consist of or comprise halogen lamps. In this way, it is possible to increase the resolution of the detection performed by the NIR video camera 31.

[0090] According to a preferred aspect of the present invention, the identification and separation apparatus 100 comprises a substantially box-shaped body 8 which defines a chamber inside which the transport unit 1, the first detection unit 2 and the second detection unit 3 are housed.

[0091] According to a preferred aspect of the present invention, the box-shaped body 8 also comprises an inlet 81, connected to the feeding zone ZA. Preferably, the inlet 81 is apt to receive the plurality of solid particulates M and feed them by means of gravity into the feeding zone ZA.

[0092] Preferably, moreover, the box-shaped body 8 comprises a first outlet 82 in communication with the waste zone ZS and a second outlet 83 in communication with the delivery zone ZC. According to a preferred aspect of the present invention, although not exclusively, the NIR video camera is of the type comprising an InGaAs (Indium-Gallium-Arsenide) sensor.

[0093] According to a preferred aspect of the present invention, the definition of the NIR video camera 31 is equivalent to 320 x 256 pixels.

[0094] According to a preferred aspect of the present invention, the NIR video camera 31 has a definition of at least 1 pixel every 3 mm of the conveyor belt 14 along the main development axis X1 in the second operating zone Z2.

[0095] According to a preferred aspect of the present invention, the plurality of solid particulates M has a size greater than 10 mm. In other word, each solid particulate of the plurality of solid particulates M has a size, i.e. a maximum dimension or particle size, greater than 10 mm.

[0096] More preferably, the plurality of solid particulates M has a size greater than 10 mm and less than 150 mm. Even more preferably, the plurality of solid particulates has a size greater than 10 mm and less than 70 mm. Based on experimental tests carried out by the Applicant of the present patent application, this size range of between 10 mm and 70 mm is the range which ensures the greatest detection efficiency on the part of the first detection unit 2 and the second detection unit 3. In other words, the size interval of the solid particulates between 10 mm and 70 mm allows maximization of the detection capacity of the first detection unit 2 and the second detection unit 3, namely the detection capacity of the optical selector.

[0097] The present invention also concerns a separation plant 200 which comprises an identification and separation apparatus 100 as described hitherto.

[0098] Said separation plant 200 comprises, preferably in order, by way of a non-limiting example of the invention: a feeding unit 204; a second conveyor belt 205; a screening unit 201; a third conveyor belt 202; a vibrating feeder 203; an identification and separation apparatus 100.

[0099] According to a preferred aspect of the present invention, the feeding unit 204 is configured to receive the plurality of solid particulates M. Preferably, the feeding unit 204 is operationally connected, for example by means of a second conveyor belt 205, to the screening unit 201, in particular to its inlet, in order to supply it. The feeding unit 204 is therefore located upstream of the screening unit 201. Preferably, the feeding unit 204 is a hopper.

[0100] The first conveyor belt is to be understood as being the conveyor belt 14 described above and included in the identification and separation apparatus 100.

[0101] According to a preferred aspect of the present invention, the separation plant 200 comprises a screening unit 201, having an inlet positioned and configured so as to receive the plurality of solid particulates M; said screening unit 201 is configured to separate the plurality of solid particulates M, those with a size substantially smaller than or equal to 10 mm. The screening unit 201 is therefore configured to remove the plurality of solid particulates which have a size substantially smaller than or equal to 10 mm.

[0102] According to a preferred aspect of the present invention, the screening unit 201 is positioned upstream of the identification and separation apparatus 100, in particular upstream of the transport unit 1.

[0103] Preferably, the screening unit 210 comprises an outlet, operationally connected to the identification and separation apparatus 100, for example by means of a third conveyor belt 202, forming part of the same separation plant 200. In particular, the outlet of the screening unit 201 is operationally connected, for example by means of said third conveyor 200 to the inlet 81 of the identification and separation apparatus 100. In this way, the screening unit 201 prevents the feeding to the transport unit 1 of solid particulates having dimensions substantially smaller than or equal to 10 mm, which could soil the second detection unit 3, reducing or affecting its detection efficiency.

[0104] According to a preferred aspect of the present invention, the screening unit 201 is a vibrating screen which comprises a bottom wall. The bottom wall is apt, during use, to receive the plurality of solid particulates and is provided with holes configured to separate from the plurality of solid particulates, those solid particulates which have a size substantially smaller than 10 mm.

[0105] According to a preferred aspect, the screening unit 201 comprises a collecting wall, apt to receive, by means of gravity, from the bottom wall the solid particulates substantially smaller than 10 mm.

[0106] The solid particulates with a size substantially smaller than 10 mm, therefore, are collected on the collecting wall of the vibrating screen 201. From here they may then be transferred, for example by means of a further conveyor belt of the separation plant 200, into special containers, for example so-called "big bags".

[0107] The solid particulates with a size substantially greater than 70 mm are instead conveyed on a lateral conveyor belt 202a parallel to the first conveyor belt 202, visible in the plan-view diagram of Figure 2A.

[0108] In other words, the screening unit 201 is apt to receive the plurality of solid particulates M and is configured to separate or remove from the plurality of solid particulates M those solid particulates with a size greater than or equal to 150 mm.

[0109] In brief, the screening unit 201 comprises a vibrating screen configured to define three particle size fractions of the solid particulates: a first "fine" particle size fraction with a size of between 0.1 mm and 10 mm, a second "average" particle size fraction with a size of between 10 mm and 70 mm, and a third "coarse" particle size fraction with a size of between 70 mm and 150 mm.

[0110] According to a preferred aspect of the present invention, the identification and separation plant 200 comprises, as mentioned above, a vibrating feeder 203 connected to the inlet 81 of the box-shaped body 8 and apt to receive the plurality of solid particulates M. The vibrating feeder 203 is configured to distribute, or supply, via the inlet 81, the plurality of solid particulates M to the feeding zone ZA.

[0111] Preferably, the vibrating feeder 203 is configured to distribute the plurality of solid particulates M on the conveyor belt 14, in particular on the upper surface 143, in a substantially uniform manner with respect to the width of the conveyor belt 14.

[0112] According to a preferred aspect of the present invention, the screening unit 201 mentioned hitherto is a first screening unit and the separation plant 200 also comprises a primary screening grille 206 associated with the feeding unit 204 in order to prevent the entry into the feeding unit 204 of solid particulates with a size preferably greater than 150 mm.

[0113] Preferably, the primary screening grille 206 is a mesh or sieve with a through-aperture of 150 mm.

[0114] In short, the feeding unit 204 comprises a hopper with a primary grille having a mesh of 150 mm for sorting solid particulates with a size greater than 150 mm, collected in a special big bag.

[0115] The present invention also concerns a method for separating and identifying asbestos-containing waste or fragments MCA in a plurality of solid particulates M and separating said asbestos-containing waste or fragments MCA from the remaining asbestos-free solid particulates MNA of the plurality of solid particulates M.

[0116] In particular, said separation method can be implemented by means of a separation apparatus 100, and in some embodiments, by a plant 200, as described above. In the description of this method, the elements of the identification and separation apparatus 100 and / or of the identification and separation plant 200 involved in the method and having the same function and the same structure as the elements described above retain the same reference number and are not described again in detail.

[0117] The separation method comprises the following sequence of steps: a step a) which involves transporting the plurality of solid particulates M from a feeding zone ZA to a first operating zone Z1; a step b) which involves emitting, via an infrared beam source 21 of a first detection unit 2, an X-ray beam towards the first operating zone Z1 so as to strike the plurality of solid particulates M present in the first operating zone Z1; a step c) which involves receiving and detecting by means of an X-ray sensor 22 the X-rays emitted by the X-ray source 21; a step d) which involves transporting the plurality of solid particulates M from the first operating zone Z1 to a second operating zone Z2; a step e) which involves acquiring images of the plurality of solid particulates M present in the second operating zone Z2 by means of an NIR video camera 31 operating in the near infrared band; a step f) which involves processing a signal or image generated by the first detection unit 2 and an image generated by the second detection unit 3 in order to identify asbestos-containing waste or fragments MCA in the plurality of solid particulates M; a step g) which involves moving by means of the separation means 5 the asbestos-containing waste MCA from the second operating zone Z2 to the waste zone ZS.

[0118] According to a preferred aspect of the present invention, the asbestos-free solid particulates or fragments or agglomerates MNA of the plurality of solid particulates M, which are not identified by the control unit 4 as asbestos-containing waste NCA, are sent to a delivery zone ZC. Preferably, said asbestos-free solid particulates MNA are sent to the delivery zone ZC by the transport unit 1.

[0119] From the delivery zone ZC these asbestos-free solid particulates MNA may be collected in suitable containers or further disposed of or used in other production processes as secondary raw material.

[0120] According to a preferred aspect, steps a), c) and d) can be implemented by means of the transport unit 1. Preferably, during the steps a), c) and d), the plurality of solid particulates is distributed in a substantially uniform manner, namely at a substantially regular or uniform distance from each other, on the upper face 143 of the conveyor belt 14.

[0121] According to a preferred aspect of the present invention, the step f) involves processing a signal or image generated by the first detection unit 2 and an image generated by the second detection unit 3 in order to identify asbestos-containing waste or fragments MCA in the plurality of solid particulates M. Preferably, the step f) is conducted by means of the aforementioned control unit 4.

[0122] According to a preferred aspect of the present invention, the step g) involves emitting via at least one blowing nozzle 51 a jet of pressurized fluid having a trajectory apt to strike the asbestos-containing waste MCA during use present in the second operating zone Z2.

[0123] According to a preferred aspect, the separation method comprises a step h), upstream of the step a), namely before the step a), which involves separating or removing from the plurality of solid particulates M the solid particulates having a size substantially smaller than or equal to 10 mm. Preferably, the step h) is performed, i.e. carried out, by means of a first screening unit 201. Expressed differently, the step h) involves feeding the first screening unit 201 with the plurality of solid particulates M and separating or removing from the plurality of solid particulates M the solid particulates with a size substantially smaller than or equal to 10 mm. In addition, preferably, said solid particulates with a size substantially smaller than or equal to 10 mm are transferred into special containers, for example so-called "big bags".

[0124] According to a preferred aspect, the separation method comprises a step i), upstream of the step h), which involves separating or removing from the plurality of solid particulates M the solid particulates having a size substantially greater than or equal to 150 mm. Preferably, the step i) is performed, i.e. carried out, by means of a second screening unit 204. Expressed differently, the step i) involves feeding the second screening unit 204 with a plurality of solid particulates M and separating or removing from the plurality of solid particulates M the solid particulates with a size substantially greater than or equal to 150 mm. In addition, preferably, the solid particulates with a size substantially greater or equal to 150 mm are disposed of in special containers, for example so-called "big bags".

[0125] According to a preferred aspect, the separation method comprises a step I), downstream of the step h) or downstream of the step i), which involves separating from the plurality of solid particulates M the solid particulates having a size substantially greater than or equal to 70 mm. Preferably, this step is performed, i.e. carried out or executed, manually by an operator. In addition, preferably, the solid particulates with size substantially greater or equal to 70 mm are disposed of in special containers, for example so-called "big bags".

[0126] According to a preferred aspect of the present invention, the step e) involves providing illumination means 32, as part of the second detection unit 3, configured to generate a visible light beam and to position said illumination means towards the second operating zone Z2; in this way, the plurality of solid particulates M present in the second operating zone Z2 is well-illuminated.

[0127] In brief, the innovation proposed by the identification and separation apparatus described above consists in the use of the automatic selector consisting of the combined technology of an NIR telecamera and an X-ray sensor, for the detection of the fragments containing asbestos MCA within a flow of solid particulates M and the separation thereof by means of compressed air jets emitted from dispensing nozzles.

[0128] The apparatus 100 for identifying and removing or separating the asbestos-containing fragments MCA, or asbestos-containing waste MCA, from the flow of solid particulates M is composed of the following elements: a conveyor belt with a speed preferably equal to 4 m / s (adjustable), preferably associated with a vibrating system for uniformly distributing the incoming solid particulates and preferably associated with a hopper; a source 21 and an X-ray sensor 22, preferably of the dual energy type, able to define any asbestos-containing fragments MCA which cannot be identified by the NIR scan since they are covered with dust or buried in the material in transit; an optical system for detecting the spectrometry, composed of an NIR video camera 31 for identifying and classifying the material in transit, namely the solid particulates M, which material is preferably illuminated by illumination means 32 (such as a set of halogen lamps which are directed onto a white background; said "white" background is provided in such a way as to optimize the action of the NIR video camera 31 and the X-ray sensor 22 with the software mode, of the known type already described above); separation means, such as a set of compressed-air blowing nozzles 51, preferably controlled by electrovalves, for the separation of the asbestos-containing fragments MCA, i.e. the recognized MCA waste, from the remaining asbestos-free fragments or particulates MNA of the plurality of particulates.

[0129] As already mentioned, a selection deviator 9 for collecting the fragments of MCA is preferably provided. The flow of asbestos-free solid particulates MNA passes beyond the deviator 9 towards the delivery zone ZC, while the remaining asbestos-containing fragments MCA, or MCA waste, are deviated by the compressed air flow underneath the deviator 9, towards the waste zone ZS.

[0130] The subject-matter of the present disclosure has been described hitherto with reference to its embodiments. It is to be understood that other embodiments relating to the same inventive idea may exist, all of these falling within the scope of protection of the claims which are attached below.

Claims

1. Identification and separation apparatus (100) for identifying and separating asbestos-containing solid waste (MCA) from other solid particulates, wherein said separation apparatus (100) comprises: - a transport unit (1) configured to transport a plurality of solid particulates (M) from a feeding zone (ZA) to a first operating zone (Z1) and from the first operating zone (Z1) to a second operating zone (Z2); - a first detection unit (2) which in turn comprises: - an infrared beam source (21) configured to emit an X-ray beam towards said first operating zone (Z1) so as to strike said plurality of solid particulates (M) during use present in said first operating zone (Z1), and - an X-ray sensor (22) configured to receive and detect X-rays emitted by said X-ray source (21); - a second detection unit (3) comprising a video camera (31) operating in the near infrared (NIR) band and arranged to focus on the second operating zone (Z2) in order to acquire images of the plurality of solid particulates (M) during use present in said second operating zone (Z2); - separation means (5) configured to separate asbestos-containing waste (MCA) from the remaining asbestos-free solid particulates (MNA) of said plurality of solid particulates (M), - a control unit (4), connected to said first detection unit (2) and to said second detection unit (3) and configured and / or programmed to identify asbestos-containing waste (MCA) in the plurality of solid particulates (M) and to operate said separation means (5).

2. Identification and separation apparatus (100) according to claim 1, wherein said separation means (5) are configured to move said asbestos-containing waste (MCA) from said second operating zone (Z2) to a waste zone (ZS).

3. Identification and separation apparatus (100) according to claim 1, wherein the transport unit (1) comprises a conveyor belt (14) which extends mainly along a main development axis (X1) between a rear portion (141) and a front portion (142) and has an upper face (143) suitable for supporting the plurality of solid particulates (M); wherein the feeding zone (ZA) corresponds to a zone overlying the upper face (143) along the rear portion (141), the second operating zone (Z2) corresponds to a zone overlying the upper face (143) along the front portion (142) and the first operating zone (Z1) corresponds to a zone overlying the upper face (143) and interposed between the second operating zone (Z2) and the feeding zone (ZA).

4. Identification and separation apparatus (100) according to claim 3, wherein the separation means (5) comprise at least one blowing nozzle (51) arranged in the vicinity of said second operating zone (Z2) and configured to emit a jet of pressurized fluid having a trajectory apt to strike asbestos-containing waste (MCA) when said asbestos-containing waste (MCA) is moving away from the end of said front portion (142) of said conveyor belt (14).

5. Identification and separation apparatus (100) according to claim 3, wherein the separation means (5) comprise a plurality of blowing nozzles (50) arranged in series transverse to the main development axis (X) downstream of said second operating zone (Z2); and wherein the control unit (4) is configured and / or programmed to actuate a nozzle (51) of the plurality of nozzles (40) to generate a jet of fluid having a trajectory apt to strike an asbestos-containing waste (MCA) during use present in said second operating zone (Z2).

6. Identification and separation apparatus (100) according to any one of the preceding claims, wherein the second detection unit (3) comprises illumination means (32) configured and positioned to generate a visible light beam towards the second operating zone (Z2).

7. Identification and separation plant (200) comprising in order: - a feeding unit (204), - a second conveyor belt (205), - a screening unit (201), - a third conveyor belt (202), - a vibrating feeder (203), - an identification and separation apparatus (100) according to one or more of claims 1 to 6.

8. Identification and separation plant (200) according to the preceding claim, comprising: - an identification and separation apparatus (100) according to any one of the preceding claims, - a screening unit (201), which has an inlet suitable for receiving the plurality of solid particulates (M) and is configured to separate from the plurality of solid particulates (M) solid particulates having a size smaller than, or equal to, 10 mm and wherein the screening unit (201) is positioned upstream of the identification and separation apparatus (100).

9. Identification and separation apparatus (200) according to claim 8, further comprising a vibrating feeder (203) adapted to receive said plurality of solid particulates (M) and operationally connected to the screening unit (201) in order to feed it.

10. Identification and separation method for identifying asbestos-containing waste (MCA) in a plurality of solid particulates (M) and separating said asbestos-containing waste (MCA) from the remaining asbestos-free solid particulates (MNA) of the plurality of solid particulates (M), wherein said identification and separation method (100) comprises the following sequence of steps: - a step a) involving transporting the plurality of solid particulates (M) from a feeding zone (ZA) to a first operating zone (Z1); - a step b) involving emitting via an infrared beam source (21) an X-ray beam towards the first operating zone (11) so as to strike the plurality of solid particulates (M) present in the first operating zone (11) - a step c) involving receiving and detecting by means of an X-ray sensor (22) the X-rays emitted by the X-ray source (21); - a step d) involving transporting the plurality of solid particulates (M) from the first operating zone (Z1) to a second operating zone (Z2); - a step e) involving acquiring images of the plurality of solid particulates (M) present in the second operating zone (Z2) by means of a video camera (31) operating in the near infrared (NIR) band; - a step f) involving processing a signal or image generated by the first detection unit (2) and an image generated by the second detection unit (3) in order to identify asbestos-containing waste (MCA) in the plurality of solid particulates (M); - a step g) involving moving the asbestos-containing waste (MCA) from the second operating zone (Z2) to a waste zone (ZS) by means of separation means (5).

11. Identification and separation method according to the preceding claim, wherein said step g) involves emitting through at least one blowing nozzle (51) a jet of pressurized fluid having a trajectory apt to strike the asbestos-containing waste (MCA) during use present in the second operating zone (Z2).

12. Identification and separation method according to claim 10 or 11, wherein the separation method comprises a step h), upstream of said step a), which involves separating or removing from said plurality of solid particulates (M) the solid particulates having a size substantially less than or equal to 10 mm.

13. Identification and separation method according to claim 11 or 12, comprising a step i), upstream of said step h), which involves separating or removing from said plurality of solid particulates (M) solid particulates having a size substantially greater than or equal to 150 mm.

14. Identification and separation method according to the preceding claim, comprising a step I), downstream of said step h) or downstream of said step i), which involves separating from said plurality of solid particulates (M) solid particulates having a size substantially greater than or equal to 70 mm.

Images