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(11) | EP 1 210 981 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Apparatus and method for shredding unusable industrial products, such as tyres, or similar |
| (57) Apparatus and method for shredding unusable industrial products, such as tyres or
similar, comprising a plurality of shredding units (11, 20, 22, 40), each provided
with rotary shredding means (16, 17, 27, 28, 29, 30, 41). The shredding units (11,
20, 22, 40) are arranged in series to shred in succession said industrial products,
or the parts thereof already shredded by the shredding unit upstream. Conveyor means
(21, 38, 45) are provided to transport the already shredded parts from each of the
shredding units to the unit immediately downstream thereof. |
[0001] The invention refers to an apparatus for shredding, or breaking into little pieces, industrial products which can no longer be used, such as tyres for means of transport in general, or similar.
BACKGROUND OF THE INVENTION
[0002] It has now become a serious problem to dispose of industrial products which can no longer be used, including tyres, both for reasons connected with protecting the environment and also because it is useful to recover and recycle the materials contained therein, particularly rubber or metal materials.
[0003] Conventional apparatuses consist of a single shredding unit, with a pair of counter-rotating shafts, on which metal disks provided with shredding teeth are mounted. Although they do obtain a crude shredding of the industrial products, these conventional apparatuses are not able to reduce the products to be treated into very small fragments, nor to recover in full the basic materials contained therein.
SUMMARY OF THE INVENTION
[0004] The apparatus and method for shredding no longer usable industrial products according to the invention are set forth and characterized in the main claims, while the dependent claims describe other innovative features of the invention.
[0005] One purpose of the invention is to perfect a method and achieve an associated apparatus which will allow to fragment into very small pieces, having the dimension of some decimillimetres approximately, no longer usable industrial products such as tyres for means of transport in general and motor vehicles in particular, which will allow to recover the materials contained therein, and which will be reliable and automated.
[0006] In accordance with this purpose, the apparatus for shredding no longer usable industrial products, such as tyres or similar, according to the invention, comprises at least two shredding units, each provided with rotary shredding means, which are arranged in series to successively shred said industrial products, or the parts thereof which have already been shredded by the shredding unit upstream, and conveyor means able to transport the parts already shredded by each of said shredding units to the unit immediately downstream thereof.
[0007] Advantageously there can be four shredding units, of which: the first two consist of units with two counter-rotating shafts, provided with shredding disks; a third is provided with four parallel shafts rotating in reciprocally opposite angular directions, wherein each shaft is provided with shredding disks and wherein a punched plate is positioned under said shafts to determine the size of the shredded material; and a fourth consists of a rotary drum grinder provided with a plurality of blades which are able to pass very close to corresponding fixed counterblades in order to tear away and split the rubber from any ferrous filaments.
[0008] The conveyor means comprise conveyor belts able to convey the shredded parts emerging from the lower part of each shredding unit towards the upper part of the subsequent shredding unit.
[0009] The apparatus according to the invention also provides: one or more deferrization units, able to separate the iron materials from the rest of the shredded pieces, a storage silo, one or more granulators, able to farther fragment the non-ferrous materials, and one or more vibrating screens, able to separate the shredded pieces according to size.
[0010] The method for shredding no longer usable industrial products according to the invention comprises at least two shredding steps performed in series by at least two shredding units, each provided with rotary shredding means, a preliminary step of loading the industrial products into a first shredding unit, and one or more intermediate steps of transporting the shredded pieces from each shredding unit to the downstream shredding unit, by means of conveyor means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] These and other characteristics of the invention will become clear from the following description of a preferred form of embodiment, given as a non-restrictive example, with the aid of the attached drawings wherein:
- Fig. 1
- is a side view of a shredding apparatus according to the invention;
- Fig. 2
- is a plane view of the apparatus shown in Fig. 1;
- Fig. 3
- is a view from above of a first shredding unit of the apparatus in Fig. 1;
- Fig. 4
- is a transverse section along a line from A to A of Fig. 3;
- Fig. 5
- is a view from above of a third shredding unit of the apparatus in Fig. 1;
- Fig. 6
- is a transverse section along a line from B to B of Fig. 5;
- Fig. 7
- is an enlarged detail of a fourth shredding unit of the apparatus in Fig. 1;
- Fig. 8
- is a partial transverse section of the fourth shredding unit of the apparatus in Fig. 1.
DETAILED DESCRIPTION OF A PREFERENTIAL EMBODIMENT
[0012] With reference to Figs. 1 and 2, a shredding apparatus 10 according to the invention comprises a first shredding unit or station 11, into which the industrial products to be shredded are able to be loaded from above, by means of a first driven conveyor belt 12.
[0013] The shredding unit 11 comprises a pair of parallel shafts 13 and 15 (Figs. 3 and 4), driven to rotate in opposite angular directions. A plurality of metal disks 16 and 17 are keyed onto each shaft 13 and 15, each provided with shredding teeth 18 and respectively 19. Fixed counterblades 16a and 17a are interposed between the disks 16 and respectively 17 to increse the cutting and shredding effect of disks 16 and 17. The shredding unit 11 has advantageously bigger dimensions than the following shredding units, because it has to perform the heavy work to rough the bulky material.
[0014] In the lower part of the shredding unit 11 an extraction belt 14a, with metal slats, is arranged, able to convey the shredded pieces towards a second driven conveyor belt 21.
[0015] A second shredding unit or station 20 (Figs. 1 and 2), identical to the first but advantageously smaller, is arranged downstream of the first to perform in sequence a second shredding step.
[0016] The second driven conveyor belt 21 is able to convey the shredded pieces, which are transported by the extraction belt 14a towards the upper part of the second shredding unit 20.
[0017] In the lower part of the shredding unit 20 there is an extraction belt 14b, also with metal slats, which is able to convey the shredded pieces towards a third driven conveyor belt 38.
[0018] Downstream of the second shredding unit 20 there is a third shredding unit or station 22, able to perform a third shredding step.
[0019] The third driven conveyor belt 38 is able to convey the shredded pieces, which are transported by the extraction belt 14b, towards the upper part of the third shredding unit 22. The latter, unlike the first two shredding units 11 and 20, comprises four parallel rotary shafts 23, 24, 25 and 26 (Figs. 5 and 6), driven to rotate in reciprocally opposite angular directions. A plurality of metal disks 27, 28, 29 and 30 are keyed onto each shaft 23, 24, 25 and 26, each one provided with shredding teeth 31, 32, 33 and respectively 34. To be more exact, each outer disk 27 and 30 has four shredding teeth, 31, respectively 34, arranged offset with respect to each other by 90°, while each inner disk 28 and 29 has two shredding teeth 32, respectively 33, arranged on diametrically opposite sides.
[0020] Below the four groups of metal disks 27, 28, 29 and 30 there is a cradle 36 constituted by a punched plate provided with a plurality of through holes 37, which has the purpose to allow the shredded pieces smaller than the size of the holes 37 to fall down. The punched plate 36 is shaped so as to define a lower compartment which thickness S is variable between about 1 and 2 cm, in accordance with the type of material to be shredded.
[0021] In the lower part of the shredding unit 22 there is a 2-way extraction belt 14c, which is selectively able to convey the shredded pieces towards a discharge belt 35, in the event the shredded material has to feed a furnace for the production of electric power, or towards a fourth driven conveyor belt 45, in the event the shredded material needs to be further shredded to reach a smaller granulometry.
[0022] Downstream of the third shredding unit 22 there is a fourth shredding unit or station 40, consisting of a grinder which comprises a rotary drum 41 provided with a plurality of metal elements, or cutting-knives, 42, which are able to cooperate, rotating, with two fixed elements, or counterblades, 43 and 44, to further shred the already shredded pieces arriving from the third shredding unit 22. The cutting-knives 42 are provided to pass very close to the fixed counterblades 43 and 44, in order to tear away and split the rubber from any ferrous filaments. A fourth driven conveyor belt 45 is able to convey the shredded pieces emerging from the lower part of the third shredding unit 22 towards the upper part of the fourth shredding unit 40.
[0023] A fifth driven conveyor belt 46 is able to convey the shredded pieces emerging from the lower part of the fourth shredding unit 40 towards the upper part of a storage silo 48.
[0024] In correspondence with the upper part of the conveyor belt 46 there is a first deferrization unit 49 of the over belt type and a second deferrization unit 50 of the CMT type, able to separate the ferrous material from the rest of the shredded pieces in a conventional manner.
[0025] Downstream of the storage silo 48 the following are arranged in series: two granulators 51 and 52, of a conventional type, which contribute to further fragment the non-ferrous materials arriving from the storage silo 48; four vibrating screens 53, 54, 55 and 56, also of a conventional type, which separate the pieces shredded by the units upstream according to size, and a series of other deferrization units 57, of the DMC type.
[0026] The apparatus 10 also comprises two cooling assemblies 58 and 59, associated respectively with the fourth shredding unit 40 and the storage silo 48, to adequately cool the shredded material contained therein.
[0027] The method for shredding no longer usable industrial products by means of the apparatus 10 as described heretofore comprises a step of loading the industrial products to be shredded into the first shredding unit 11, a first shredding step by means of the first shredding unit 11, a possible second shredding step by means of the second shredding unit 20, and a third shredding step by means of the third shredding unit 22.
[0028] According to a simplified variant, the second shredding step can be eliminated, and the method passes directly from the first to the third shredding step.
[0029] Subsequent to the third shredding step, there is a fourth shredding step which is performed by means of the grinder 40 with the rotary drum 41.
[0030] Downstream of the fourth shredding step there is at least a deferrization step, to eliminate the ferrous parts from the shredding path. For the remaining parts a further step is then provided to reduce them into grains, and a subsequent step of final deferrization, in the course of which any residual ferrous parts, possibly included in the shredded parts, are eliminated.
1. Apparatus for shredding unusable industrial products, such as tyres or similar, the
apparatus being characterized in that at least two shredding units (11, 22), each provided with rotary shredding means
(16, 17, 27, 28, 29, 30), are arranged in series to shred in succession said industrial
products, or the parts thereof already shredded by the shredding unit upstream, conveyor
means (21, 38) being provided to transport said already shredded parts from each of
said shredding units to the unit immediately downstream thereof.
2. Apparatus as in Claim 1, characterized in that the shredding means of at least one of said shredding units (22) comprise four parallel
shafts (23, 24, 25 and 26), rotating in reciprocally opposite angular directions,
and that on each of said four rotary shafts (23, 24, 25, 26) a plurality of metal
disks (27, 28, 29, 30) are mounted, each one provided with shredding teeth (31, 32,
33, 34).
3. Apparatus as in Claim 1, characterized in that each of said metal disks (27, 30) keyed onto the two outermost rotary shafts (23,
26) is provided with four shredding teeth (31, 34) arranged offset by 90° with respect
to each other, and that each of said metal disks (28, 29) keyed onto the two innermost
rotary shafts (24, 25) is provided with two shredding teeth (32, 33) arranged on diametrically
opposite sides.
4. Apparatus as in Claim 1, characterized in that below the four pluralities of said metal disks (27, 28, 29, 30) there is a cradle
element (36) constituted by a punched plate shaped so as to define a compartment with
a pre-determined thickness (S) variable between about 1 and 2 cm, in accordance with
the type of material to be shredded.
5. Apparatus as in Claim 1, characterized in that said shredding units comprise a first shredding unit (11) into which the industrial
products to be shredded are able to be loaded from above.
6. Apparatus as in Claim 5, characterized in that said first shredding unit (11) comprises a pair of parallel shafts (13, 15) driven
to rotate in opposite angular directions, on each shaft (13, 15) of said pair of shafts
a plurality of metal disks (16, 17) being keyed, each provided with shredding teeth
(18, 19).
7. Apparatus as in Claim 5, characterized in that said conveyor means comprise a first extraction belt (14a), arranged in the lower
part of said first shredding unit (11) and able to convey the shredded pieces towards
a second driven conveyor belt (21), which in turn is able to convey them towards a
second shredding unit (20).
8. Apparatus as in Claim 7, characterized in that said second shredding unit (20) is identical to said first shredding unit (11), but
advantageously of smaller dimensions.
9. Apparatus as in Claim 7, characterized in that in the lower part of said second shredding unit (20) is arranged a second extraction
belt (14b) able to convey the shredded pieces towards a third driven conveyor belt
(38).
10. Apparatus as in Claim 9, characterized in that said first and second extraction belts (14a, 14b) include metal slats.
11. Apparatus as in Claim 9, characterized in that said third driven conveyor belt (38) is able to convey the shredded pieces towards
a third shredding unit (22).
12. Apparatus as in Claim 11, characterized in that said third shredding unit (22) comprises four parallel shafts (23, 24, 25 and 26)
rotating in reciprocally opposite angular directions, and that on each of said four
rotary shafts (23, 24, 25, 26) a plurality of metal disks (27, 28, 29, 30) are mounted,
each one provided with shredding teeth (31, 32, 33, 34).
13. Apparatus as in Claim 11, characterized in that downstream of said third shredding unit (22) there is a fourth shredding unit (40)
consisting of a rotary drum grinder (41).
14. Apparatus as in Claim 13, characterized in that at least a deferrization unit (49) able to separate the ferrous materials from the
rest of the shredded pieces, is arranged downstream of said fourth shredding unit
(40).
15. Apparatus as in Claim 14, characterized in that a storage silo (48) is arranged downstream of said deferrization unit (49).
16. Apparatus as in Claim 15, characterized in that downstream of said storage silo (48) two granulators (51, 52) are arranged in series,
able to further fragment the non-ferrous materials arriving from said storage silo
(48).
17. Apparatus as in Claim 16, characterized in that downstream of said granulators (51, 52) a plurality of vibrating screens (53, 54,
55, 56) are arranged in series, able to separate, according to size, the pieces shredded
upstream.
18. Apparatus as in Claim 17, characterized in that downstream of said vibrating screens (53, 54, 55, 56) there is at least another deferrization
unit (57).
19. Apparatus as in Claim 15, characterized in that two cooling units (58, 59) are associated respectively to said fourth shredding unit
(40) and to said storage silo (48) to adequately cool the shredded material contained
therein.
20. Method to shred unusable industrial products, such as tyres or similar, characterized in that it comprises at least two shredding steps performed in series by at least two shredding
units (11, 22), each provided with rotary shredding means (16, 17, 27, 28, 29, 30),
a preliminary step of loading said industrial products into a first of said at least
two shredding units (11), and one or more intermediate steps of transporting the shredded
pieces from each of said shredding units (11) to the shredding unit downstream, by
means of conveyor means (21, 38).
21. Method as in Claim 20, characterized in that at least one of said shredding steps occurs in a shredding unit (22) which comprises
four parallel shafts (23, 24, 25 and 26) rotating in reciprocally opposite angular
directions, and wherein on each of said four rotary shafts (23, 24, 25, 26) a plurality
of metal disks (27, 28, 29, 30) are mounted, each provided with shredding teeth (31,
32, 33, 34).
22. Method as in Claim 20, characterized in that at least three shredding steps are provided, performed in series by an equal number
of shredding units (11, 20, 22) each provided with rotary shredding means (16, 17,
27, 28, 29, 30).
23. Method as in Claim 22, characterized in that the first two of said three shredding steps occur in two corresponding shredding
units (11, 20) each of which comprises a pair of parallel shafts (13, 15) driven to
rotate in opposite angular directions, wherein a plurality of metal disks (16, 17),
each provided with shredding teeth (18, 19), are keyed onto each shaft (13, 15) of
said pair of shafts.
24. Method as in Claim 20, characterized in that at least four shredding steps are provided, performed in series by an equal number
of shredding units (11, 20, 22, 40) each one provided with rotary shredding means
(16, 17, 27, 28, 29, 30, 41).
25. Method as in Claim 24, characterized in that the fourth shredding step is performed by means of a grinder (40) with a rotary drum
(41).
26. Method as in Claim 24, characterized in that downstream of the fourth shredding step at least a deferrization step is provided,
to eliminate the ferrous parts from the shredding path and that, for the remaining
parts, there is a further step of reducing into grains and a subsequent step of final
deferrization, in the course of which any possible ferrous remnants still present
in the shredded parts are eliminated.