DK202200670A1

DK202200670A1 - A loading unit for a conveying system for receiving waste objects through an inlet opening in the loading unit and use of said loading unit

Info

Publication number: DK202200670A1
Application number: DKPA202200670A
Authority: DK
Inventors: From Hansen Preben; Haug Harald
Original assignee: Nordic Recycling Systems Group As
Priority date: 2022-07-11
Filing date: 2022-07-11
Publication date: 2024-02-16
Also published as: WO2024012977A1

Abstract

A loading unit (4) for a conveying system (1) for receiving waste objects (2) through an inlet opening (24) in the loading unit (4). The waste objects are devices such as empty beverage bottles and cans of any size. The loading unit (4) comprises an outlet port (6) through which the objects (2) leave the loading unit (4). The loading unit (4) is used in a pneumatic conveying system (1) that comprises pressure devices (8,9) for providing pressurized air/gas. The outlet port (6) of the loading unit (6) is a pneumatic outlet tube (POT) 1 arranged for establishment of a suction in the POT (6); A pneumatic inlet tube (5) (PIT) of the loading unit is arranged for establishment of a positive pressure. By the suction and pressure, the waste objects (2) leave the loading unit (4) through the POT (6).

Description

DK 2022 00670 A1 1

The present invention relates to a loading unit for a conveying system for receiving waste objects through an inlet opening in the loading unit, the loading unit comprises an outlet port through which the objects leave the loading unit.

Further the invention relates to use of use of the loading unit in a pneumatic conveying system comprising pressure devices for establishing the suction in the pneumatic outlet tube -POT- and the positive pressure in the pneumatic inlet tube - PIT.

Finally, the invention relates to use se of the loading unit for a container return system for waste material such as empty beverage bottles and cans of any size.

This waste material may be items such as empty beverage bottles and cans of any size and material such as, plastic, steel, aluminum, glass, plastic said waste material is recycling waste material.

Pneumatic outlet tube is abbreviated to POT and pneumatic inlet tube is abbreviated to PIT.

Pneumatic conveying systems are used for transporting different kind of material such as food, corn and granulates. Generally, air is blown through pipes via a pressure blower and similar in order to move the material through the pipe. In this way the material in question can be moved from one point to another point.

A container return system is generally arranged to collect waste containers for recycling. This may include used emptied beverage bottles and cans, or other waste material.

The container return system must collect large numbers of waste material for recycling in a short period of time. In many installations, the container return system delivers the received objects to a backroom receiving facility and the

DK 2022 00670 A1 2 required space here can be considerable. Further it can also require means for sorting and storing the received objects. The space requirement and the complexity cause cost to the system.

In a typical installation, the crushed or compressed objects are transferred to a box and stored in plastic bags. The plastic bag is replaced when full. This also requires available space to store the full plastic bag and is time consuming. Further the container return system is often stopped when the box is full and an empty one is placed.

In order to handle recycling packages such as bottles and cans it is common to transport the objects on a transport band. This transport band runs from a delivery station, where the customer puts the bottle/can and to a box where the bottles/cans are collected.

Such system is known from WO 2022/013343. After the cans or bottles have been crushed, the crushed waste material is falling onto a buffer arrangement, and is further distributed and transported through the accompanying carrier assembly to be stored in a storage bin, which will contain the crushed material.

However, such a buffer arrangement/collecting unit for dropping down the items is not possible to use when the distribution and transport of the items is done by pneumatic lines. A pneumatic line for transporting the items has the advantage, that the waste material is transported away from the delivery station so fast, that the user just can empty large portions of the waste material into the delivery station without any risk for overloading the system.

Further, instead for a small box or plastic bag to collect the transported items a large container can be placed outside the building where the system is working. The demand for staff to handle the reverse vending machine is thereby also reduced.

With other words it is desirable to be able develop an improved loading unit for a pneumatic working convey system for collecting and transporting waste

DK 2022 00670 A1 3 material in such a way that the waste material can be handled without any delay. The waste material is transported from the delivery station down to the loading unit and away from here so fast that the user just can empty large portions of the waste material into the delivery station from where it drops down into the loading unit without any risk for overloading the system.

The present invention seeks generally to improve loading units for handling waste objects such as bottles and cans such that the abovementioned insufficiencies and drawbacks of today’s loading units are overcome or at least it provides a useful alternative.

Up to this day, prior art has failed to teach a simple and yet reliable and inexpensive loading units which in a safe and reliable manner, without substantially increasing the cost of the system, is able to satisfy the abovementioned much desired characteristics of the mentioned loading units.

According to the invention, a pneumatic conveying system is provided, as per the introductory part of this specification, and wherein the loading unit is adapted to be used in a pneumatic conveying system, the pneumatic conveying system comprises pressure devices for providing pressurized air/gas; the outlet port of the loading unit is a pneumatic outlet tube (POT) arranged for establishment of a suction in the POT; the loading unit further comprises a pneumatic inlet tube (PIT) arranged for establishment of a positive pressure by said suction and pressure the waste objects leave the loading unit through the POT.

The pressure devices may comprise any type of air-source such as a blower, air pump, fan, or other device capable of creating a pressure differential and for forcing air or other fluid, under pressure, through the loading unit. As such, the pressure devices are configured to generate a positive air-pressure in the

PIT and a suction in the POT.

DK 2022 00670 A1 4

As the waste material - such as empty plastic bottles or cans - drop down in the loading unit and reaches the bottom of this, a laminar flow in the loading unit caused by the pressure difference between the inlet convey line and the outlet convey line is sucked into the POT and passes to a collecting unit which is typically a big container placed outside the building where the system is placed.

The loading unit receives the waste material without any delay, and as the waste material leaves the loading unit as soon they have reached the bottom of the unit through the POT, the loading unit can operate nearly through the whole day without any interruptions.

The loading unit combines pneumatic vacuum transport and pneumatic overpressure transport and a control system controls the two pressures in such a way that we have nearly even pressure (0,9-1 bar) in the center of the loading unit, and a laminar flow of around 15-35 m/second. The waste material is in this way pushed into the POT of the loading unit, where the under-pressure sucks the material to a discharge convey line from where it is dropped down into the container.

According to one embodiment the loading unit comprises a horizontal tube comprising the PIT and POT, and the loading unit further comprises a hopper placed above the tube and connected to the tube with its walls and with an outlet opening in the bottom, allowing the objects to drop down into the tube through an opening in said tube.

The tube acts in this way as the bottom of the loading unit. The upper part of the collecting unit for guiding the objects is formed as a hopper, and comprises an opening in the bottom matching an opening of the tube. The hopper is typically connected to the tube by welding the lower edge of the hopper to the outside wall of the tube. The tube thus forms the bottom of the loading unit and is airtight connected to the hopper.

According to one embodiment the hopper comprises the inlet opening which

DK 2022 00670 A1 is surrounded by the walls of the hopper, and opposite the inlet opening the walls surround the outlet opening and the tube comprises a bottom of the loading unit.

The outlet opening of the hopper has a size that allows the waste material to 5 pass unhindered through but also sees to, that the waste material does not clump together and causes the loading unit to be overfilled and causes it to stall.

According to one embodiment that the walls of the hopper comprise four sidewalls a first side wall, a second side wall, a third sidewall, a fourth sidewall connected to each other forming a rectangular cross-section, and the shape of the two opposite sidewalls having the largest length-extent and placed parallel with the longitudinal axes of the tube is trapezoidal shaped, whereby the two other opposite placed sidewalls placed above PIT and POT are slanted arranged relative to the vertical plane.

According to one embodiment the two opposite sidewalls having the largest length-extent are inclined relative to the vertical plane and converging towards the outlet opening.

By forming the hopper as described is achieved that the waste material slide down to the bottom as the sloping walls ensure optimal transport, and that the waste material lies with the longitudinal axis substantially parallel with the longitudinal axes of the loading unit.

According to one embodiment the rectangular cross-section area of the inlet opening is larger than the rectangular cross-section area of the outlet opening.

This helps to support the correct placement of the waste material in the loading unit

According to one embodiment the POT comprises openings placed at the

DK 2022 00670 A1 6 lower part of the wall of the POT.

The conveying system may be contaminated by residues from the waste material dropped down in the loading unit. Waste containers returned for recycling, such as empty beverage bottles or cans, often contain residual liquids, which may come into contact with the system. In order to clean the system, the POT has 10-20 openings with a diameter each of 2-3 mm placed at the lower part of the wall of the POT. When water is dropped down in the loading unit it is sucked into the POT and due to the small openings, air from the outside is also sucked into the POT, working as an injector. This causes the water to atomize and is sucked further into the system cleaning it.

According to one embodiment the pressure in the loading unit and in the PIT and the POT is controlled by a control-system configured to control the air/gas pressure from pressure devices, by said pressure the objects pass from the loading unit through the POT of the loading unit and through a discharge convey line to a collecting unit.

According to one embodiment the control system is adapted to control the pressure in such a way, that a laminar airflow is obtained in the region of the loading unit placed between PIT and POT, which is around 15-35 m/s, and the pressure in the POT is below 1 bar an ambient atmospheric pressure, and the pressure in the PIT is above 1 bar an ambient atmospheric pressure.

The control system is adapted to control the pressure in the loading unit in such a way, that a laminar airflow in center of the loading unit is around 15- 35 m/s, and the pressure in the POT is below 1 bar an ambient atmospheric pressure, and the pressure in the PIT is above 1 bar an ambient atmospheric pressure.

The control system sees to that the air flow velocity in the loading unit is suitable, that is around 15-35 m/s, preferably 25-30 m/s. This is done by regulating the pressure in PIT and the POT.

DK 2022 00670 A1 7

According to one embodiment a sensor is placed in relation to the loading unit said sensor is configured to register janming of the loading unit.

The sensor is placed close to the loading unit in an opening in one of the walls of the hopper. The sensor registers if something goes wrong such as there is a risk of constipation of the loading unit.

By pneumatic transfer tubes is to understand, that the tubes are transporting under-pressure or over-pressure gas/air and are able to withstand the different pressures.

According to one embodiment the loading unit is placed on a frame arrangement.

The loading unit is placed on a frame arrangement, which is adapted to the conveying system also in the height.

Brief description of the drawings

FIG. 1 is a perspective view of a loading unit according to the invention.

FIG. 2 is a sectional view through a loading unit shown in fig 1.

FIG. 3 is a perspective view of a pneumatic conveying system in which a loading unit as shown in fig 1 is arranged.

The invention will be explained with reference to fig. 1 and 2. This shows a loading unit 4 for receiving waste objects 2 — not shown - through an inlet opening 24 in the loading unit 4. The loading unit 4 is adapted to be an integrated part of a pneumatic conveying system 1 as shown in fig. 3 that comprises pressure devices 8,9 for providing pressurized air/gas.

The loading unit 4 comprises a pneumatic outlet tube POT 6 through which the objects 2 leave the loading unit 4. A suction is established in POT 6.

DK 2022 00670 A1 8

The objects are then transported through a discharge convey line 7 to a collecting unit 3 as shown in fig. 3.

The loading unit 4 further comprises a pneumatic inlet tube 5 (PIT) arranged for establishment of a positive pressure. By the suction and pressure the waste objects 2 leave the loading unit 4 through the POT 6.

The loading unit comprises a horizontal tube 19 comprising the PIT 5 and

POT 6. The loading unit 4 further comprises a hopper 20 placed above and on the tube 19 and connected to the tube 19 with its walls. It has an outlet opening 25 in the bottom, allowing the objects 2 to drop down into the tube 19 through an opening 32 in the tube 19. The tube 19 comprises a bottom 33 of the loading unit 4 and the outlet opening 25 has a size the allows the objects such as bottles and cans to pass unhindered through.

The walls of the hopper 20 comprises four sidewalls a first side wall 27, a second side wall 28, a third sidewall 29, a fourth sidewall 30. They are connected to each other forming a rectangular cross-section. The shape of the two opposite sidewalls 28,30 having the largest length-extent placed parallel with the longitudinal axes of the tube 19 is trapezoidal shaped. The two other opposite placed sidewalls 27,29 placed above PIT 5 and POT 6 - that is in the front and in the back - are slanted arranged. They are inclined relative to the vertical plane. The two opposite sidewalls 28,30 having the largest length extent are also inclined relative to the vertical plane.

As a result, the waste objects 2 slide down to the bottom of the loading unit 4 as the slanted sidewalls direct the waste objects 2. The rectangular cross- section ensures that objects 2 are placed with their longitudinal axis parallel to the tube 19. As a result of the slanted arrangement and the diameter of the tube 19 is smaller than the width of the inlet opening 24, the rectangular cross-section area of the inlet opening 24 is larger than the rectangular cross-section area of the outlet opening 25.

DK 2022 00670 A1 9

The POT 6 comprises openings 17 placed at the lower part of the wall of the POT 6. The number of openings 17 is around 10-20, each with a diameter of 2-3 mm placed at the lower part of the wall of the POT 6. When water is dropped down in the loading unit 4 it is sucked into the POT 6 and due to the small openings 17, air from the outside is also sucked into the

POT6, working as an injector. This causes the water to atomize and is sucked further into the system 1 the loading unit 4 is attached to and cleaning it.

A sensor in placed in relation to the loading unit 4. An opening 34 is made in one of the walls of the hopper 20 for placing and giving access to the sensor. The sensor will register jamming of the loading unit 4. The loading unit 4 is placed on a frame arrangement 21 in order to place it correct in relation to the pneumatic conveying system 1

A pneumatic conveying system is shown in fig 3 suitable for the loading unit 4 according to the invention.

An object 2 such as a plastic bottle is thrown down in the loading unit 4 for being transported through pneumatic conveying tubes. The object 2 is typically delivered from a deliver-station placed in a store, where the customer delivers his bottles/cans back to the store in order to have the waste objects 2 recycled. An object 2 is also seen in fig. 3 leaving the system through an outlet 14 of a pneumatic discharge convey tube 7. The objects 2 - delivered to the system 1- is delivered as a continuous flow. The customer may simply empty a whole sack of objects 2 into the deliver- station as the loading unit 4 is able to receive and handle the objects 2 without any delay.

Air/gas is flowing through the PIT 5, the central part of the loading unit 4 and POT 6. The POT 6 is flow connecting with an injector 11 through a second convey line 12, which is also air/gas flow connected to the discharge convey line 7. A pressure device such as a pressure blower 8

DK 2022 00670 A1 10 provides pressurized gas/air and is through a first convey line 18 air gas connected with the injector 11 and thereby the discharge tube 7.

The pressure blower 8 forms a negative air/gas pressure in the POT 6 due to the established gas/air flow lines through the injector 11.

An air/gas pump 9 generates an air/gas flow through the PIT 5. A laminar airflow is then obtained in the central part of the loading unit 4 - around 15- 35 m/s - due to the pressure in the POT 6 is below 1 bar an ambient atmospheric pressure (suction), and the pressure in the PIT 5 is above 1 bar an ambient atmospheric pressure. Thereby the objects 2 pass from the loading unit 4 through the injector 11 and the discharge convey line 7, through the outlet 14 of the discharge convey line 7 into a collecting unit 3.

The pressure is controlled by a control system 10.

The control system 10 controls the pressure in such a way, that the laminar airflow is obtained in the central region of the loading unit, and the pressure in the POT 6 and in the PIT 5 is as described above.

The loading unit 4 according to the invention may off course be used in other pneumatic conveying systems than the one described.

Claims

DK 2022 00670 A1 11 Claims

1. A loading unit (4) for a conveying system (1) for receiving waste objects (2) through an inlet opening (24) in the loading unit (4), the loading unit (4) comprises an outlet port (6) through which the objects (2) leave the loading unit (4), characterized in that the loading unit (4) is adapted to be used in a pneumatic conveying system (1) that comprises pressure devices (8,9) for providing pressurized air/gas; the outlet port (6) of the loading unit (6) is a pneumatic outlet tube (POT) arranged for establishment of a suction in the POT (6); the loading unit (4) further comprises a pneumatic inlet tube (5) (PIT) arranged for establishment of a positive pressure by said suction and pressure the waste objects (2) leave the loading unit (4) through the POT (6).

2. A loading unit (4) according to claim 1 characterized in that the loading unit comprises a horizontal tube (19) comprising the PIT (5) and POT (6), and the loading unit (4) further comprises a hopper (20) placed above the tube (19) and connected to the tube (19) with its walls and with an outlet opening (25) in the bottom, allowing the objects (2) to drop down into the tube (19) through an opening (32) in said tube (19).

3. A loading unit (4) according to claim 2 characterized in that the hopper (20) comprises the inlet opening (24) which is surrounded by the walls of the hopper (20), and opposite the inlet opening (24) the walls surround the outlet opening (25) and the tube (19) comprises a bottom (33) of the loading unit (4).

4. A loading unit (4) according to claim 2 or 3 characterized in that the walls of the hopper (20) comprise four sidewalls a first side wall (27),

DK 2022 00670 A1 12 a second side wall (28), a third sidewall (29), a fourth sidewall (30) connected to each other forming a rectangular cross-section, and the shape of the two opposite sidewalls (28,30) having the largest length- extent and placed parallel with the longitudinal axes of the tube (19) is trapezoidal shaped, whereby the two other opposite placed sidewalls (27,29) placed above PIT (5) and POT (6) are slanted arranged relative to the vertical plane.

5. A loading unit (4) according to claim 4 characterized in that the two opposite sidewalls having the largest length-extent are inclined relative to the vertical plane and converging towards the outlet opening (25).

6. A loading unit (4) according to claim 3,4 or 5 characterized in that the rectangular cross-section area of the inlet opening (24) is larger than the rectangular cross-section area of the outlet opening (25).

7. A loading unit (4) according to any of the preceding claims characterized in that the POT (6) comprises openings (17) placed at the lower part of the wall of the POT.

8. A loading unit (4) according to any of the preceding claims characterized in that the pressure in the loading unit (4) and in the PIT (5) and the POT (6) is controlled by a control-system (10) configured to control the air/gas pressure from a pressure device (8,9), by said pressure the objects (2) pass from the loading unit through the POT (6) of the loading unit (4) and through a discharge convey line (7) to a collecting unit (3).

9. A loading unit (4) according to any claim 8 characterized in that the control system (10) is adapted to control the pressure in such a way, that a laminar airflow is obtained in the region of the loading

DK 2022 00670 A1 13 unit (4) placed between PIT (5) and POT (6), which is around 15-35 m/s, and the pressure in the POT (6) is below 1 bar an ambient atmospheric pressure, and the pressure in the PIT (5) is above 1 bar an ambient atmospheric pressure.

10. A loading unit according to any of the preceding claims characterized in that a sensor is placed in relation to the loading unit (4) said sensor is configured to register jamming of the loading unit

(4).

11. A loading unit according to any of the preceding claims characterized in that the loading unit (4) is placed on a frame arrangement (21).

12. Use of a loading unit (4) according to claim 1-11 in a pneumatic conveying system (1) comprising pressure devices (8,9) for establishing the suction in POT (6) and the positive pressure in the PIT (5).

13. Use of a loading unit (4) according to claim 1-12 for a container return system for waste material such as empty beverage bottles and cans of any size.