Plant for glass recovery from bottles, food CANS, and similar items

Abstract

Plant (10) for recovering glass from bottles, food jars, and similar items, comprising a roller mill (11), a descent hopper (12), a washing tank (13), a conveying screw (14) partially immersed with its rear section in said washing tank (13), a washing conduit (15) housing the conveying screw (14) in operation, washing means (16) for the glass fragments. At least a rear section (15a) of the washing conduit (15) features a matrix of filtration holes. The washing means (16) are positioned at a front section (15b) of the washing conduit (15).

Description

[0001] PLANT FOR GLASS RECOVERY FROM BOTTLES, FOOD CANS, AND SIMILAR ITEMS

[0002] DESCRIPTION

[0003] Technical field

[0004] The present invention relates to a plant for the recovery of glass from bottles, food cans, and similar items.

[0005] Background

[0006] Nowadays, there is an increasing and widespread need, especially for food production companies, to recover glass from shelf-packaged containers that are not sold within the time limits set by food shelf life dates, such as bottles of alcoholic beverages or jars of creamy sweets like jams, hazelnut creams, or jars of food preserved in oil or vinegar, and other similar packaging.

[0007] Industries like bars, restaurants, hotels, and vaccination centers also manage large volumes of single-use glass, which, once emptied or only partially emptied, must be recycled.

[0008] To reduce the volume of glass bottles, jars, and glass containers, glass crushing plants are known today that crush bottles and jars and reduce their volume by 80% or even up to 90%.

[0009] The key to effective glass recycling lies in the proper disposal, selection, and storage of this material, resulting in benefits in terms of collection volumes and reduced transportation costs.

[0010] There are currently known crushers, or cylinder mills, used for destroying glass containers of beverages and alcoholic drinks. These mills optimally crush glass from bottles and completely destroy bottles and similar containers, even with their contents inside, allowing for subsequent separation of the glass, liquids, metal caps, corks, and plastic.

[0011] Such cylinder mills are particularly useful for glass recyclers dealing with scrap, glass manufacturers that need to crush faulty bottles, and food, beverage, alcoholic, and pharmaceutical producers for the destruction of expired, spoiled, or defective goods.

[0012] While these well-known cylinder mills are appreciated by the market, they have a significant drawback related to washing the crushed glass, which often retains organic residues that are difficult to remove. Today, no matter how thoroughly a glass container is washed before crushing, it still shows traces of dirt that risk compromising its proper recovery.

[0013] Another issue with known cylinder mills is that they produce a certain amount of glass dust, which is very difficult to manage.

[0014] Summary of the invention

[0015] The main objective of the present invention is therefore to develop a plant for the recovery of glass from bottles, food jars, and similar containers, which overcomes the issues mentioned above with reference to the known technique.

[0016] A particular aim of the present invention is to develop a plant for glass recovery that improves the cleanliness of glass intended for reuse.

[0017] Another goal of the present invention is to develop a plant for glass recovery that allows for optimal management of glass dust.

[0018] The above-mentioned task and objectives are achieved by a plant for the recovery of glass from bottles, food jars, and similar containers, according to claim 1.

[0019] Preferred features of the present invention are the subject of the dependent claims.

[0020] Other advantages, characteristics, and modes of use of the present invention will become apparent from the following detailed description of an embodiment, presented for illustrative purposes and not limiting.

[0021] Description on the figures

[0022] Reference will be made to the following figures, illustrative of an embodiment of the invention: Figure 1 represents a schematic side view of a plant for the recovery of glass from bottles, food jars, and similar containers according to the invention.

[0023] - Figure 2 represents an alternative embodiment of a portion of the plant according to the invention.

[0024] The thicknesses and curvatures shown in the figures above are to be understood as purely illustrative, generally exaggerated, and not necessarily shown to scale.

[0025] Detailed Description of Preferred Embodiments

[0026] The following describes various embodiments and variants of the invention, with reference to the figures introduced above. Similar components are denoted in the different figures with the same reference number.

[0027] In the detailed description that follows, additional embodiments and variants, beyond those already addressed in the description, will be illustrated, limited to the differences from what has already been presented.

[0028] Furthermore, the various embodiments and variants described below are susceptible to being used in combination, where compatible.

[0029] Initially referring to Figure 1 , a plant for the recovery of glass from bottles, food jars, and similar items is indicated as a whole with the number 10.

[0030] This plant 10 comprises:

[0031] - a roller mill 11 ,

[0032] - a descending hopper 12,

[0033] - a washing tank 13,

[0034] - a conveying screw 14, partially immersed in the washing tank 13,

[0035] - a washing conduit 15, where said conveying screw 14 operates; at least one rear section 15a of said washing conduit 15 has a matrix of filtration holes;

[0036] - washing means 16 for the glass fragments; the washing means are positioned at the front section 15b of said washing conduit 15.

[0037] The washing tank 13 is positioned below the descending hopper 12. The descending hopper 12 is configured and shaped to guide the broken glass pieces descending from the roller mill 11 into the rear section 15a of the washing conduit 15.

[0038] The conveying screw 14 operates inside the washing conduit 15. The conveying screw 14 is substantially coaxial with the washing conduit 15.

[0039] In a first embodiment variant of the plant 10 according to the invention, the roller mill 11 is of the type with two counter-rotating cylinders 11a and 11b. At least one of the counter-rotating cylinders, and preferably each of the counterrotating cylinders 11a and 11 b, is supported by thrust means configured to push one counter-rotating cylinder 11a towards the opposite counter-rotating cylinder 11 b.

[0040] In an embodiment variant of the plant according to the invention, schematized in Figures 2 and marked with the number 110, the roller mill 111 comprises two pairs of counter-rotating cylinders, an upper pair 130 and a lower pair 131 , where the minimum distance L1 between the surfaces of the counterrotating cylinders of the upper pair 130 is greater than the minimum distance L2 between the surfaces of the counter-rotating cylinders of the lower pair 131 .

[0041] Preferably and advantageously, the counter-rotating cylinders 11a and 11 b feature an ordered matrix of gripping holes. The term "ordered matrix of gripping holes" refers, in the context of the present disclosure, to a plurality of holes, preferably arranged in a systematic arrangement, such as a grid or geometric pattern, preferably in regular rows and / or columns. This arrangement preferably follows a defined and constant configuration.

[0042] In particular, and even more advantageously, the counter-rotating cylinders 11a and 11 b are coated with a material that has a high coefficient of friction relative to glass, such as rubber or other technically equivalent material. In other words, preferably, the counter-rotating cylinders 11a and 11 b are coated with a material having a coefficient of friction greater than 0.5, more preferably greater than 0.7, and even more preferably greater than 1.1. Thanks to the gripping holes and the high-friction coating, the roller mill 11 is able to pull forward even glass bodies and glass fragments that are particularly slippery, for example, due to being coated with oily fluids.

[0043] The washing means include heating means 20 for the washing water, and a plurality of injectors 21 configured to spray water inside the washing conduit 15.

[0044] The conveying screw 14 and the washing conduit 15 that surrounds the conveying screw 14 are inclined so that the rear section 15a is substantially immersed in the washing tank 13, while the front section with the washing means is above the water level in the washing tank 13.

[0045] The washing tank 13 appropriately includes a skimmer partition 23 configured to define a secondary tank 24 for the removal of substances and floating bodies, such as oily substances, organic residues, debris, and floating bodies or particles.

[0046] The secondary tank 24 is operatively connected to an upper pump 25 for extracting such substances and floating bodies from the water surface.

[0047] The secondary tank 24 also includes a drainage and filtration system 26 positioned at the bottom.

[0048] The washing tank 13 also has a drainage and filtration system 27 positioned to operate near the bottom of the tank 13.

[0049] Downstream of the washing conduit 15, there is a iron removal device 40.

[0050] The iron removal device 40 is positioned to operate, for example, and not limited to, above a conveyor belt 41 , which is in turn positioned and configured to receive the glass fragments and any other non-glass bodies exiting the discharge opening 15a of the washing conduit 15.

[0051] The iron removal device 40 can be, for example, an electromagnetic conveyor belt acting above the conveyor belt 41 , capable of removing any ferrous bodies such as crown caps and similar items.

[0052] Advantageously, the conveying screw 14 may be of the type with a variable pitch helix, meaning it has a first narrower pitch configured to also recover any glass dust particles, and a second wider pitch to speed up the advancement and have a larger volume between two consecutive helices, so that the glass fragments can pass through a larger free washing volume and thus be better washed by the hot water sprayed.

[0053] In a variant of an plant according to this disclosure, it may include an overflow tank 42, fluidically connected to the washing conduit 15 to receive organic material from it by overflow, which, when the plant is in operation, floats — or is brought to the surface — in the liquid present in the washing conduit 15.

[0054] In particular, the overflow tank 42 may include an overflow edge 421 that limits an overflow opening, which preferably directly connects the overflow tank with the washing conduit.

[0055] The overflow edge 421 is positioned slightly below the level of the washing liquid, which, during the operation of the plant, is present in the washing tank.

[0056] The term "slightly below" means that the level of the overflow edge 421 is at a lower vertical height than the level of the washing liquid — depending on the specific construction conditions of this invention — such that the organic floating material in the washing liquid is spilled over the washing conduit 15 and dragged upward by the conveying screw 14, so that this spillage is sufficient to prevent the conveying screw from dragging organic material into the front section 15b of the washing conduit 15.

[0057] In other words, the overflow tank 42 is configured and positioned so that organic material contained in the washing conduit 15 and dragged upwards by the conveying screw 14 is discharged into it by overflow from the overflow edge 421.

[0058] An extraction pump 43 can be connected to the overflow tank 42, preferably at the bottom of the latter, to extract the fluid F that accumulates in it during the operation of the plant 10.

[0059] It has been observed that the invention achieves the task and objectives set forth.

[0060] In particular, the invention provides a glass recovery system that, thanks to the washing means with hot and temperature-adjustable water, allows for optimal washing of the glass fragments before they proceed to a subsequent grinding stage, after which washing would be practically impossible.

[0061] A glass recovery system according to the invention improves the cleaning of glass intended for reuse and consequently significantly improves the quality of the products made from such recycled glass.

[0062] Additionally, with the present invention, a system for glass recovery has been developed that enables optimal management of glass dust.

[0063] The present invention has been described so far with reference to preferred embodiments. It is to be understood that other embodiments may exist that pertain to the same inventive core, as defined by the scope of protection of the claims provided below.

Claims

CLAIMS1. Plant (10) for the recovery of glass from bottles, food cans and the like comprising- a roller mill (11 )- a descent hopper (12)- a washing tank (13)- a conveying screw (14), immersed for its rear section in said washing tank (13)- a washing conduit (15), in which said conveying screw (14) is placed to operate, at least a rear section (15a) of said washing conduit (15) having a matrix of filtration holes- washing means (16) of said glass fragments, said washing means (16) being positioned at a front section (15b) of said washing conduit (15).

2. Plant according to claim 1 , wherein said roller mill (11 ) is of the two counter-rotating cylinder type (11a, 11 b), at least one counter-rotating cylinder being supported by thrust means configured to push one said counter-rotating cylinder (11a) towards the opposite other counter-rotating cylinder (11 b).

3. Plant according to one or more of the preceding claims, wherein said roller mill (111 ) comprises two pairs of counter-rotating cylinders, an upper pair (130) and a lower pair (131 ), wherein the minimum distance (L1 ) of the surfaces of the counter-rotating cylinders of the upper pair (130) is greater than the minimum distance (L2) of the surfaces of the counter-rotating cylinders of the lower pair (131 ).

4. Plant according to one or more of the preceding claims, wherein said counter-rotating cylinders (11a, 11 b) have an ordered matrix of clamping holes.

5. Plant according to one or more of the preceding claims, wherein saidcounter-rotating cylinders (11a, 11 b) are coated with a coating having a high coefficient of friction with respect to glass, for example with a rubber coating.

6. Plant according to one or more of the preceding claims, wherein the washing means (16) comprise washing water heating means (20) and a plurality of injectors (21 ) configured to spray water into said washing conduit. (15)7. Plant according to one or more of the preceding claims, wherein said conveying screw (14) and said washing conduit (15) surrounding said screw are inclined so that said rear section (15a) is substantially submerged in said washing tank (13), while said front section (15b), with said washing means (16), is above the surface of the water present in said washing tank (13).

8. Plant according to one or more of the preceding claims, wherein said washing tank (13) comprises a floodway septum (23) configured to define a secondary tank (24) for removing floating substances and bodies, such as oily substances, organic residues and debris, floating bodies or corpuscles, said secondary tank (24) being operatively connected to an extraction pump (25) of said floating substances and bodies.

9. Plant according to one or more of the preceding claims, wherein an iron removal device (40) is present downstream of said washing conduit (15).

10. Plant according to the preceding claim, wherein said iron removal device (40) is of the magnetic belt type.

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