Scope of the invention
[0001] This invention falls within the area of equipment for plastic recycling, more specifically,
this invention concerns an equipment that performs the breaking/disintegrating/ decompacting
and drying of the plastic submitted to washing and compacting, more specifically,
to an equipment joinable to a compacting equipment, for breaking and drying of plastic
film waste for recycling after the washing process. These stages are part of the plastic
film recycling process.
Context of the invention
[0002] With increasing awareness of the environmental problems that result from the use
of plastics, and the impossibility of, in a short period of time, replacing the products
manufactured in this material by others that are equally durable and with equivalent
costs, its recycling is increasingly the option chosen to process plastics that are
no longer useful in the role they were performing.
[0003] The facilities to recycle plastic and the equipment that enables this recycling were
thus born.
[0004] A recycling system is defined as a facility consisting of a set of devices that are
serially connected and that, having independent functions, interact with each other
and enable the complete processing of waste until a product that can be reused as
raw material is obtained.
[0005] This process usually consists of the following phases:
- 1 - Grinding
- 2 - Washing or decontamination
- 3 - Drying
- 4 - Granulation or pelletizing
Grinding
[0006] In this phase of the process, the material is reduced to a size that enables the
following phases to be carried out. Depending on the materials to be processed, this
phase may be interleaved with washes until the material is the size and state of cleanliness
that enable it to be moved on to the next phase.
Washing or decontamination
[0007] In this phase, the goal is to separate the material from the contaminants that accompany
it, be they soil (in agricultural films or others), remnants of various products (in
packaging), paper, glues or even incompatible plastic materials. The devices used
in this stage vary depending on the materials to be processed and may act alone or
jointly to obtain the best result.
Drying
[0008] The goal is for the material, after this operation, to present a level of humidity
between 2% and 5%.
[0009] The grinded and washed material carries with it considerable amounts of water and,
despite being separated in the transport worms that make the connection between the
system's various devices, and that are endowed with perforated plate bottoms to facilitate
this separation, excess water must be removed so the material can be processed, in
the next phase, by the extruder, granulator or pelletizer. This operation is performed
by high-rotation centrifuges in perforated plate tanks, enabling the outflow of liquids
and other impurities that are separated in the centrifugation process. In some materials,
such as film, it is necessary to use more than one centrifuge and to operate them
serially to obtain the desired result.
[0010] Another method used for drying uses heat sources, removing moisture from the material
by evaporation. This process is, however, extremely expensive, since it requires large
amounts of energy to generate the necessary heat.
[0011] A third method consists of compressing the material in equipment suitable for this
purpose, with the excess water being removed by compacting the material. An example
of one of these devices can be found at
https://www.compactor-runi.com/shop/machines/runi-sk370 and in figure 4 of this patent application.
[0012] The material, after this operation, is deposited in bigbags (industrial bags made
with flexible and resistant material to transport products in bulk), transported to
storage silos or sent directly to the extruder that will carry out its granulation
or pelletizing.
Granulation or pelletizing
[0013] This operation completes the recycling cycle by providing material with a level of
purity that enables it to be reused in the production of a plethora of goods.
THE SOLUTION
[0014] In the cases where the water is removed by compacting the material, it leaves the
drying equipment as a clump/aggregated/compacted.
[0015] Taking into account that the purpose of all this processing is the granulation or
pelletizing of the material, it becomes necessary to break/disintegrate/decompact
the material, since the equipment that performs the granulation of the plastic requires
the material to be loose.
[0016] One of the existing solutions is to throw the clumps vertically, so that when they
hit the ground, they disintegrate.
[0017] The equipment of this invention enables solving this problem, through the coupling
of the compacting machine to a device that disintegrates, separates and feeds the
material, and that additionally takes advantage of the air flow necessary for the
disintegration and separation to promote a final reduction of the humidity, so that
it falls within the ideal values, that is, that it presents a level of humidity between
2% and 5%.
Background to the invention
[0018] Some documents were found that mention equipment for disintegrating/breaking/decompacting
material, focusing on soil, especially for agricultural soil.
[0019] In plastics, but not specifically for film plastic, some documents were found that
present equipment for disintegrating/decompacting. However, these documents concern
equipment for disintegrating/decompacting material arriving at factories from the
collection points for materials to be recycled. This equipment is not designed for
breaking/disintegrating/decompacting plastic film. This equipment is not designed
to break. Examples of this equipment can be found at:
https://www.eggersmann-recyclingtechnology.com/en/brt-hartner/products/feed-hopper
-dosing-hopper-with-decompactor-brt-hartner-dc/ or at
https://www.eggersmann-recyclingtechnology.com/en/brt-hartner/products/bale-breaker-brt-hartner-bb/.
[0020] No equipment was found to carry out the breaking/ disintegrating/decompacting of
plastic film waste after it has gone through washing and compacting in a plastic recycling
process.
Advantages of the invention
[0021] Compared to the solutions mentioned above, the method presented in this invention
and implemented by the equipment described in this document, i.e., the compression
of the material to remove excess water, carried out in a device suitable for this
purpose, with this stage being complemented by another, carried out in the equipment
of this invention, which breaks/disintegrates/decompacts the material and promotes
an additional drying, presents several advantages over the other methods already known.
- It enables a continuous operation, replacing several devices used in the conventional
plastic drying processes during its recycling;
- It increases productivity compared to the conventional processes;
- It reduces consumption by up to 75% when compared to other technologies used;
- It reduces the noise and vibrations inherent to the process;
- It eliminates fines (material with very small granulometry);
- It feeds equipment downstream of the recycling process in a direct, continuous and
stable way, without the need for intermediate silos.
Brief description of the figures
[0022] These and other characteristics can be easily understood using the attached drawings,
which are to be considered as mere examples and in no way restrictive of the scope
of the invention. In the drawings, and for illustrative purposes, the measurements
of some of the elements may be exaggerated and not drawn to scale. The absolute and
relative dimensions do not correspond to the real ratios for the embodiment of the
invention.
[0023] In a preferential embodiment:
Figure 1 presents a view of the invention's equipment.
Figure 2 shows a cross-sectional view of the invention's equipment.
Figure 3 shows a view of the integration of the compacting equipment with the invention's
equipment.
Figure 4 shows a view of the compacting machine.
Figure 5 shows a view of the disintegrator.
Figures 6a and 6b show two embodiments of the rotating blade.
Figure 7 shows a view of the conveyor.
Figure 8 shows a view of the integration of the conveyor with the ventilator.
Figure 9 shows a view of the ventilator.
Figure 10 shows a view of the ventilator where its interior can be seen.
Figure 11 shows a view of the ventilator where the various components inside it and
the transmission can be seen.
[0024] The elements and components of the equipment of this invention, as well as elements
necessary for the operation of the invention, are marked in the figures:
1 - Intake hopper
2 - Breaker
2.1 - Rotating blade
2.1.1 - Protrusion
2.1.1.1 - Lateral protrusions
2.1.1.2 - Central protrusion
2.2 - Breaker engine
3 - Discharge hopper
4 - Dosing feeder
4.1 - Worm screw
4.2 - Support frame
4.3 - Roller bearing
4.4 - Gearmotor
5 - Ventilator
5.1 - Ventilator inlet port
5.2 - Ventilation grilles
5.3 - Ventilator outlet port
5.4 - Turbine
5.5 - Fan blades
5.6 - Transmission
5.7 - Ventilator motor
C - Compacting machine
C.1 - Outlet port of the compacting machine
C.2 - dosing feeder inlet
Detailed description of the invention
[0025] The application of the principles described herein is not limited to the specific
embodiments presented. The principles described herein can be used with any plastic
film compression equipment to extract excess water that arises from the material washing
stage. This stage is part of the plastic recycling process.
[0026] Additionally, although some of the presented embodiments incorporate multiple new
features, these features can be independent and do not all need to be used together
in a single embodiment.
[0027] Throughout the text, "material" means plastic film waste in the state in which it
is found at any stage of the recycling process.
[0028] With reference to the figures, the invention concerns equipment that performs the
breaking and drying of the plastic film, which is in the recycling process, after
having been submitted to washing and compacting.
[0029] This equipment operates in three stages:
1st - Breaking/disintegration/decompacting
2nd - Separation and feeding
3rd - Drying and transport
[0030] In the disintegration stage, the plastic film waste coming out of the compacting
machine (C) enters the intake hopper (1) which has a parallelepiped shape, with the
face facing the compacting machine (C) open, inside which the rotating blade (2.1)
of the breaker (2), which is set in motion by the breaker engine (2.2) and which has
a specific geometry adapted to the dimensions of the compacting machine (C).
[0031] The specific geometry of the rotating blade (2.1) depends on the size of the outlet
port of the compacting machine (C.1) for the plastic film clumps.
[0032] The rotating blade (2.1) has a substantially parallelepiped shape which in an embodiment
incorporates at least one protrusion (2.1.1) on the face facing the compacting machine
(C) .
[0033] In a first embodiment (Figure 6a) the rotating blade (2.1) has three protrusions,
being two lateral protrusions (2.1.1.1) and one central protrusion (2.1.1.2). The
lateral protrusions (2.1.1.1) have a substantially rectangular triangular prismatic
shape and the central projection (2.1.1.2) has a substantially acutangular triangular
prismatic shape. In this embodiment, the outer face of the lateral protrusions (2.1.1.1)
is substantially coplanar with the outer face of the rotating blade (2.1).
[0034] In a second embodiment (Figure 6b) the rotating blade (2.1) has three protrusions,
being two lateral protrusions (2.1.1.1) and one central protrusion (2.1.1.2). The
lateral protrusions (2.1.1.1) have a substantially prismatic pentagonal oblique convex
shape and the central protrusion (2.1.1.2) a substantially triangular prismatic shape.
In this embodiment, the outer lateral face of the lateral protrusions (2.1.1.1) is
substantially coplanar with the outer lateral face of the rotating blade (2.1) and
the oblique face of the lateral protrusions (2.1.1.1) is adjacent to the outer lateral
face of the lateral protrusions (2.1.1.1).
[0035] After the plastic has been properly disintegrated by the rotating blade (2.1), the
separation and feeding phase begins. This phase begins with the plastic falling, which,
due to gravity, drops into the discharge hopper (3) where a dosing feeder (4) that
incorporates a worm screw (4.1) separates it further. This dosing feeder (4), in addition
to the worm screw (4.1), consists of a support frame (4.2) to which a roller bearing
(4.3) and a gearmotor (4.4) are attached. For reasons of stability and operability,
the support frame (4.2) is fixed inside the compacting machine (C), and the passage
of the dosing feeder (4) is carried out through the dosing feeder inlet (C.2). This
stage, in addition to disintegrating and separating the plastic, enhances the correct
and stable feeding for the 3rd stage, since the worm screw (4.1) of the dosing feeder
(4) carries the correct amount to the ventilator (5).
[0036] The 3rd stage, during which drying and transport take place, is carried out in the
ventilator (5). The material guided by the dosing feeder (4) enters the ventilator
(5) through the ventilator inlet port (5.1) by means of the air flow caused by the
movement of the turbine (5.4), which is put into operation by the ventilator motor
(5.7) that transmits the movement to the transmission (5.6), which in turn is transmitted
to the turbine (5.4) and is conducted to the fan blades (5.5) that promote its final
separation, being then sent to the ventilator outlet port (5.3) and then fed to the
equipment downstream of the disintegrator and dryer equipment of the invention, so
that the plastic waste, properly cut, washed and separated is granulated or pelletized.
[0037] The drying of the material is carried out in the material's path between the ventilator
inlet port (5.1) and the ventilator outlet port (5.3), solely due to the circulation
of air inside the ventilator (5).
[0038] The ventilation grilles (5.2) are of vital importance for the entire process, as
they avoid stopping the equipment in the event that the ventilator inlet port (5.1)
becomes blocked. Sometimes the rotating blade (2.1) does not disintegrate the material
and the material falls into the discharge hopper (3) and therefore into the dosing
feeder (4), still in a clump. This clump is guided by the worm screw (4.1) into the
ventilator inlet port (5.1), blocking it due to its size. With the ventilator inlet
port (5.1) blocked, the air flow circulating inside the equipment falls to values
close to zero, causing the pressure inside the equipment to drop, which leads to clogging
of the pipe that routes the material to the ventilator outlet port (5.3). Since the
ventilation grilles (5.2) are placed in an area next to the clump's location, the
entry of air through the ventilation grilles (5.2) allows pressure to continue to
exist inside the ventilator (5), preventing it from stopping. This clump will eventually
be disintegrated due to the continuous motion of the worm screw (4.1) and of the fan
blades (5.5).
1. Equipment for breaking and drying plastic film waste to recycle wherein it comprises:
a breaker (2), a dosing feeder (4) and a ventilator (5).
2. Equipment according to claim 1, wherein the breaker (2) comprises a rotating blade
(2.1) and a breaker engine (2.2) .
3. Equipment according to claim 1, wherein the dosing feeder (4) comprises a worm screw
(4.1), a support frame (4.2), a roller bearing (4.3) and a gearmotor (4.4).
4. Equipment according to claim 1, wherein the ventilator (5) comprises a ventilator
inlet port (5.1), ventilation grilles (5.2), a ventilator outlet port (5.3), a turbine
(5.4), fan blades (5.5), a transmission (5.6) and a ventilator motor (5.7).
5. Equipment according to claim 2, wherein the rotating blade (2.1) has a substantially
parallelepiped shape.
6. Equipment according to claim 5, wherein the rotating blade (2.1) comprises at least
one protrusion (2.1.1) on the face facing the compacting machine (C).
7. Equipment according to claim 6, wherein the rotating blade (2.1) has three protrusions,
being two lateral protrusions (2.1.1.1) and one central protrusion (2.1.1.2); the
lateral protrusions (2.1.1.1) have a substantially rectangular triangular prismatic
shape and the central protrusion (2.1.1.2) has a substantially acutangular triangular
prismatic shape; the outer face of the lateral protrusions (2.1.1.1) is substantially
coplanar with the outer face of the rotating blade (2.1).
8. Equipment according to claim 6, wherein the rotating blade (2.1) has three protrusions,
being two lateral protrusions (2.1.1.1) and one central protrusion (2.1.1.2); the
lateral protrusions (2.1.1.1) have a substantially prismatic pentagonal oblique convex
shape and the central protrusion (2.1.1.2) has a substantially triangular prismatic
shape; the outer lateral face of the lateral protrusions (2.1.1.1) is substantially
coplanar with the outer lateral face of the rotating blade (2.1) and the oblique face
of the lateral protrusions (2.1.1.1) is adjacent to the outer lateral face of the
lateral protrusions (2.1.1.1).
9. Use of the equipment in claim 1 in a plastic film waste recycling process.
10. Process for breaking and drying plastic film waste using the equipment claimed in
claim 1 wherein the following stages are included:
a) Breaking stage
- Plastic film waste clumps are inserted into the equipment through an intake hopper
(1),
- The rotating blade (2.1) of the breaker (2) that rotates inside the intake hopper
(1) performs the breaking/disintegrating/decompacting of the plastic film waste clumps,
b) Separation and dosage feed stage
- The plastic film waste falls into a discharge hopper (3),
- a dosing feeder (4) integrated in the discharge hopper (3), which incorporates a
worm screw (4.1), performs an additional separation,
- The plastic film waste is routed to the ventilator (5),
c) Drying and transport stage
- Plastic film waste guided by the dosing feeder (4) enters the ventilator (5) through
the ventilator inlet port (5.1) due to the air flow caused by movement of the turbine
(5.4), which is operated by the ventilator motor (5.7) that transmits movement to
the transmission (5.6), which in turn is transmitted to the turbine (5.4),
- The plastic film waste is guided to the fan blades (5.5) that promote its final
separation and is then routed to the ventilator outlet port (5.3),
- The plastic film waste is directed to the equipment downstream of the disintegrator
and dryer equipment.