WASTE TREATMENT DEVICE

Description

Title Waste treatment device SIB-BI1150E - 1 WASTE TREATMENT DEVICE DESCRIPTION This disclosure generally refers to a device for treating waste. Specifically, this disclosure refers to a device for treating waste from digesters or water treatment plants. Nowadays, devices called separators are known to treat waste in order to separate materials that can be recovered and reused from other waste materials. For example, there are well-known household waste separators, which are particularly suitable for separating plastic waste from other solid and / or organic waste. Nowadays, however, there is a significant need for separators specifically configured to treat other types of materials besides household waste. Specifically, there is a strong need for separators specifically configured to treat material from digesters, whether agricultural, dry, or semi-dry digesters, or for the treatment of digestate exiting from OFMSW digesters, to obtain a clean substance that can be directly used, for example, for agricultural purposes. There is also a strong need for separators configured to treat water, particularly water from water treatment plants, such as sewage treatment plants and / or salt water. The substances treated in this specific technical field are substantially different from those traditionally treated in conventional separators. While the latter are specifically designed to treat predominantly solid materials, such as household waste, materials from digesters or water treatment plants are configured to treat a predominantly liquid substance, in which the dry, or solid, portion constitutes, for example, only 15%–30% of the total substance. For this purpose, traditional separators cannot be used, also considering the different specific gravities of the substance to be treated. In this regard, the materials coming from the digesters can be composed of liquid substance, predominantly water, with a specific gravity equal to or close to 1, a dry portion, with a specific gravity between 0.6 and 0.9, and any plastic materials generally with a specific gravity between 0.3 and 0.5. This material to be treated is substantially much denser than that of the SIB-BI1150E -2 municipal waste. Therefore, it requires waste treatment devices, or separators, with substantially different characteristics than conventional separators. The problem underlying this disclosure is therefore that of effectively treating material deriving from digesters in order to obtain a product that can be directly used in the agricultural sector. The aim of the present invention is therefore to provide a waste treatment device, or separator, particularly configured for the treatment of material deriving from digesters. Another task of this disclosure is to create an apparatus that, in addition to effectively treating material deriving from digesters to obtain a substance directly usable in the agricultural sector, is structurally simple, easy to use and maintain, as well as durable and reliable. This task, as well as other purposes which will become clearer below, are achieved by a waste treatment device according to the attached independent claim. Detailed features of a waste treatment device according to the present disclosure are set forth in the dependent claims which are incorporated herein by reference. Further features and advantages of the present disclosure will become more apparent from the description of a preferred, but not exclusive, embodiment of a waste treatment device according to the present disclosure illustrated by way of example and not by way of limitation in the figures of the attached drawings, in which: - Figure 1 represents a sectional view of a waste treatment device according to one aspect of the present disclosure; - Figure 2 is a sectional view of a waste treatment device according to one aspect of the present disclosure; - Figure 3 shows a plan view of a shaft with associated hammers of a waste treatment device according to one aspect of the present disclosure; - Figures 4 and 5 show plan views of first hammers of a waste treatment device according to one aspect of the present disclosure; - Figures 6 and 7 show plan views of first hammers of a waste treatment device according to one aspect of the present disclosure. With reference to the attached figures, an embodiment of a waste treatment device is indicated by the reference number 100. The term “waste processing device” in this disclosure means a device configured to squeeze material for recovery mixed with other waste. SIB-BI1150E -3 In particular, within the scope of this disclosure, the treatment device 100 is specifically configured for the treatment of waste, or material, from digesters, whether agricultural, dry, or semi-dry. This material is characterized by a high liquid fraction, consisting predominantly of water, with a specific gravity equal to or close to 1, a dry portion, with a specific gravity between 0.6 and 0.9, and possible plastic materials generally with a specific gravity between 0.3 and 0.5. Ultimately, therefore, the digester material to be treated is particularly dense, especially due to the high liquid portion. The particular composition of the waste to be treated requires a different type of separator than those traditionally known and used for the treatment of domestic waste. In particular, according to the present disclosure, the waste treatment device 100 comprises a casing 10 defining within it a substantially cylindrical cavity into which, in use, waste to be treated is inserted, for example through an inlet opening. Preferably, the material to be treated, or waste, is dosed into the cylindrical or substantially cylindrical cavity via a pump, preferably controlled by an inverter. Alternatively, the material to be treated can be dosed into the cylindrical cavity via a screw conveyor, preferably controlled by an inverter. According to the present disclosure, the device 100 further comprises a shaft 20, arranged inside the cylindrical or substantially cylindrical cavity, which is rotatable about its own rotation axis X. Preferably, such rotation axis X is placed at the center, or substantially at the center, of the cylindrical or substantially cylindrical cavity. The waste treatment device 100 according to the present disclosure further comprises a plurality of hammers. In particular, these hammers are configured to shred the waste, or in any case the material to be treated, and, at the same time, push such material forward in an axial direction, i.e., parallel to the rotation axis X, along a main direction of development of the shaft 20, inside the cavity, towards an outlet opening. In detail, according to the present disclosure, the device 100 comprises first hammers 30 and second hammers 40. The first hammers 30 are associated with the shaft 20. Preferably, each hammer of the first hammers 30 comprises a first end associated with the shaft 20, and a second end, opposite to the first, free inside the cylindrical cavity or SIB-BI1150E -4substantially cylindrical. In essence, each hammer of the first hammers 30 protrudes radially from the shaft 20. Preferably, the first hammers 30 are arranged consecutively along the shaft 20, preferably along the entire length of the shaft 20 itself. According to a preferred aspect of the present disclosure, the first hammers 30 can be rotatably associated with the shaft 20, for example through a first pin. According to this preferred aspect, the first hammers 30 are therefore pivotable with respect to the shaft 20. Each hammer of the first hammers 30 is configured to shred the waste, or in any case the material to be treated, and, at the same time, push such material forward in an axial direction, i.e. parallel to the rotation axis X, along a main direction of development of the shaft 20, inside the cavity, towards an exit opening. To this end, according to the present disclosure, the first hammers 30 have a first front cutting edge, configured to shred the material to be treated and to further push such material axially along the cylindrical or substantially cylindrical cavity. In particular, the first front edge of the first hammers 30 is configured to perform an initial shredding of the material to be treated and provide an initial thrust in the axial direction to the material to be treated itself. By “front edge” of the first hammers 30 is meant, in the context of this disclosure, the portion of the first hammers 30 which, when the shaft 20 is, in use, set in rotation, first comes into contact with the material to be treated, to shred it and push it in an axial direction. In detail, the first front cutting edge of the first hammers 30 has a first blade 31 which defines a first angle a with respect to a first lateral wall 32 of the first hammers 30 themselves. In other words, to crush material and push it axially along the cylindrical or substantially cylindrical cavity, the first front edge of the first hammers 30 has a tapered profile. According to the present disclosure, the second hammers 40 are associated with the shaft 20. Preferably, each hammer of the second hammers 40 comprises a third end associated with the shaft 20, and a fourth end, opposite to the third, free within the cylindrical or substantially cylindrical cavity. In essence, each hammer of the second hammers 40 protrudes radially from the shaft 20. Preferably, the second hammers 40 are arranged consecutively along the shaft 20, preferably along the entire length of the shaft 20 itself. According to a preferred aspect of the present disclosure, the second hammers 40 can be rotatably associated. SIB-BI1150E -5to the shaft 20, for example through a second pin. According to this preferred embodiment, the second hammers 40 are therefore pivotable with respect to the shaft 20. Each hammer of the second hammers 40 is configured to shred the waste, or in any case the material to be treated, and, at the same time, push such material forward in an axial direction, i.e. parallel to the rotation axis X, along a main direction of development of the shaft 20, inside the cavity, towards an exit opening. To this end, according to the present disclosure, the second hammers 40 have a second front cutting edge, configured to shred the material to be treated and to further push such material axially along the cylindrical or substantially cylindrical cavity. In particular, the second front edge of the second hammers 40 is configured to perform a second shredding of the material to be treated and provide a second thrust in the axial direction to the material to be treated itself. By “front edge” of the second hammers 40 is meant, in the context of this disclosure, the portion of the second hammers 40 which, when the shaft 20 is, in use, set in rotation, first comes into contact with the material to be treated, to shred it and push it in an axial direction. In detail, the second front cutting edge of the second hammers 40 has a second blade 41 that defines a second angle β with respect to a second side wall 42 of the second hammers 40 themselves. In other words, to crush material and push it axially along the cylindrical or substantially cylindrical cavity, the second front edge of the second hammers 40 has a tapered profile. According to the present disclosure, the first angle α of the first blade 41 of the first front edge of the first hammers 30 is different from the second angle β of the second blade 42 of the second front edge of the second hammers 40. Consequently, advantageously, since the shredding of the material to be treated depends directly on the configuration of the front edge, and in particular of the blade of the hammers, and since the front edge and in particular the blade of the first hammers 30 are different from that of the second hammers 40, it is possible, according to the present disclosure, to obtain different shredding and thrusts in the axial direction of the material to be treated between the first and second hammers 30, 40. In detail, according to a preferred aspect of the present disclosure, the shaft 20 comprises a main direction of development, parallel to the rotation axis X of the shaft 20 itself, and may comprise, along this main direction of development, a first portion of shaft 21 and a second portion of shaft 22, in SIB-BI1150E -6where such first portion of shaft 21 and such second portion of shaft 22 are opposite to each other, along such main direction of development of shaft 20, or along the rotation axis X of shaft 20 itself. According to this preferred aspect, the first hammers 30 are associated with the shaft 20 in correspondence with the first portion of shaft 21, while the second hammers 40 are associated with the same shaft 20 in correspondence with the second portion of shaft 22. Even more preferably, a plurality of first hammers 30 is associated with the first portion of shaft 21. Furthermore, more preferably, a plurality of second hammers 40 is associated with the second portion of shaft 22. It advantageously follows that, as the material to be treated advances axially along the cylindrical or substantially cylindrical cavity, it receives a differentiated shear and thrust treatment based on its position within the cylindrical or substantially cylindrical cavity, depending on whether it is treated by the first hammers 30 or the second hammers 40. Specifically, the material to be treated inserted into the cylindrical or substantially cylindrical cavity through the inlet opening is particularly dense; as it is pushed axially along the cylindrical or substantially cylindrical cavity, it is continuously processed, losing part of the liquid substance it contains. Consequently, its density changes, and it can be treated differently to obtain an optimal material for direct agricultural use. In other words, the material inserted into the cylindrical or substantially cylindrical cavity through the inlet opening, being particularly dense, requires greater processing, for a prolonged time, and requires greater force to be pushed axially along the cavity itself. As the material to be treated advances along the cylindrical or substantially cylindrical cavity, losing a large portion of its liquid, the material to be treated requires less processing, and a smaller pushing force to be pushed along the cavity itself. For this reason, it is particularly advantageous for the device 100 to be equipped with hammers having different front edges along the rotation axis X, or along the main direction of development, of the shaft 20. Furthermore, different hammers provided along the main direction of the shaft 20 allow to obtain different material transfer speeds, and therefore a greater or lesser processing of the same material. According to a further preferred aspect of the present disclosure, the shaft 20 may comprise a third shaft portion 23. Such third shaft portion 23 is interposed between the first shaft portion 21 and the second shaft portion 22. SIB-BI1150E -7 According to this aspect, furthermore, the device 100 comprises third hammers 60, associated with the shaft 20, in particular with the third portion of the shaft 23. These third hammers 60 comprise a third front cutting edge having a third blade defining a third angle with respect to a third lateral wall of these third hammers 60. According to this aspect, advantageously, the third angle is an angle included between the first angle a and the second angle β. In combination or alternatively, both first hammers 30 and second hammers 40 can be associated with the third portion of shaft 23. More preferably, a plurality of first hammers 30 and a plurality of second hammers 40 are associated with the third portion of shaft 23. Advantageously, according to this aspect, it is possible to obtain an even more accurate and precise treatment of the material to be treated, depending on the change in composition and density of the material to be treated as it advances into the cylindrical or substantially cylindrical cavity. In other words, the treatment of the material to be treated, in terms of crushing and thrust along the axial direction, in the third portion of shaft 23 is intermediate between that in the first portion of shaft 21 and that in the second portion of shaft 22. Preferably, according to one aspect of the present disclosure, the first angle α of the first hammers 30, defined between the first lateral edge 32 and the first blade 32 of the first hammers 30 is equal to or greater than 40°. More preferably, the first angle α of the first hammers 30 is equal to or greater than 45°. Furthermore, preferably the second angle β of the second hammers 40, defined between the second lateral edge 42 and the second blade 42 of the second hammers 40 is less than 40°. More preferably, the second angle β of the second hammers 40 is equal to 30°. Preferably, furthermore, the third angle of the third hammers 60 is an angle between 30° and 45°. For example, the third angle of the third hammers 60 is an angle equal to 40°. It therefore advantageously follows that the first hammers 30 are configured to exert a crushing and pushing action in the axial direction of the material to be treated that is different, and preferably greater, or more intense, than the second hammers 40, which are preferably arranged subsequently with respect to the first hammers 30 along the main direction of development of the shaft 20, or along the rotation axis X. According to a further preferred aspect of the present disclosure, the waste treatment device 100 comprises a second waste material collection cavity, preferably located underneath the cylindrical or substantially cylindrical cavity. According to this aspect, the device 100 further comprises a screening mesh 50, configured to separate, or divide, the cylindrical or substantially cylindrical cavity. SIB-BI1150E -8substantially cylindrical from the second cavity below. In other words, the screening mesh 50 is interposed between the cylindrical or substantially cylindrical cavity and the second cavity below. Preferably, the screening mesh 50 is positioned below the shaft 20, and preferably extends along the entire length, or substantially the entire length, of the shaft 20. Preferably, the screening mesh 50 comprises a first screening mesh sector and a second screening mesh sector, wherein the first and second screening mesh sectors are opposite each other along the axial direction, or along the main direction of development of the shaft 20. Advantageously, the first screening mesh sector is positioned in correspondence with, in particular below, the first portion of the shaft 21, while the second screening mesh sector is positioned in correspondence with, in particular below, the second portion of the shaft 22. Furthermore, according to this aspect, the first screening mesh sector comprises a plurality of first through holes in the screening mesh, each of which has a first dimension. In addition, the second screening mesh sector comprises a plurality of second through holes in the screening mesh, each of which has a second dimension. Advantageously, the second dimension is different from the first dimension. The subject matter of this disclosure has been described so far with reference to its embodiments. It is to be understood that other embodiments may exist that relate to the same inventive core, all falling within the scope of the claims set forth below.

Claims

1. Waste treatment device (100) configured to squeeze material to be recovered mixed with other waste, said device (100) comprising: a casing (10) defining within it a substantially cylindrical cavity into which to insert waste to be treated through an inlet opening, a shaft (20), rotating around its own axis of rotation, substantially at the centre of said cavity, first hammers (30), associated with said shaft (20), having a first front cutting edge having a first blade (31) defining a first angle (a) with respect to a first side wall (32) of said first hammers (30), second hammers (40), associated with said shaft (20), having a second front cutting edge comprising a second blade (41) defining a second angle (β) with respect to a second side wall (42) of said second hammers (40), wherein said first angle (a) is different with respect to said second angle (β).

2. Device (100) according to claim 1, wherein said first hammers (30) and said second hammers (40) are configured to break waste into waste shreds and to propel said waste shreds in an axially advancing direction into the first cylindrical cavity towards said exit opening.

3. Device (100) according to claim 1 or 2, wherein said shaft (20) comprises a main direction of development, said shaft (20) comprising at least a first shaft portion (21) and a second shaft portion (22), wherein said first shaft portion (21) is opposite to said second shaft portion (22) along said main direction of development, wherein said first hammers (30) are associated with said shaft (20) in said first shaft portion (21) and wherein said second hammers (40) are associated with said shaft (20) in said second shaft portion (22).

4. Device (100) according to the preceding claim, wherein a plurality of said first hammers (30) is associated with said first shaft portion (21).

5. Device (100) according to claim 3 or 4, wherein a plurality of said second hammers (40) is associated with said second shaft portion (22).

6. Device (100) according to any of claims 3 to 5, wherein said shaft (20) comprises a third shaft portion (23), interposed between said first shaft portion (21) and said second shaft portion (22), wherein said device (100) comprises third hammers (60), associated with said third shaft portion (23), having a third front cutting edge comprising a third blade defining a third angle with respect to a third lateral wall of said third hammers (60), wherein said third angle is an angle between said first angle (a) and said second angle (β).

7. Device (100) according to the previous claim, wherein a plurality of said third hammers are associated with said third portion (23) of shaft (20).

8. Device (100) according to any of the preceding claims, wherein said first angle (a) is equal to or greater than 40°.

9. Device (100) according to any of the preceding claims, wherein said second angle (β) is less than 40°.

10. Device (100) according to any of the preceding claims in combination with claim 3, comprising a second cavity for collecting waste material, underlying said substantially cylindrical cavity and a screening mesh (50) configured to separate said substantially cylindrical cavity, suitable for containing material to be recovered, from the second cavity below, intended to collect waste material, wherein said screening mesh (50) comprises a first screening mesh sector positioned in correspondence with said first shaft portion (21), and a second screening mesh sector positioned in correspondence with said second shaft portion (22), said first screening mesh sector comprising a plurality of first holes passing through said screening mesh, wherein each hole of said first plurality of holes has a first dimension,and wherein said screening mesh section comprises a plurality of second holes passing through said screening mesh, wherein each hole of said second plurality of holes has a second dimension, said second dimension being different from said first dimension.