WO1994011125A1

WO1994011125A1 - A method and device for separating components from a composite quantity of material

Info

Publication number: WO1994011125A1
Application number: PCT/NL1993/000243
Authority: WO
Inventors: Henricus Wilhelmus Van Doorne
Original assignee: Stork Protecton B.V.
Priority date: 1992-11-17
Filing date: 1993-11-17
Publication date: 1994-05-26
Also published as: EP0674549A1; NL9300421A

Abstract

A method and device for separating components from a composite quantity of material, said components having a high water rate and a low water rate respectively, for instance fat and meat components from slaughter waste meat, raisins and stones, which device is provided with a conveyor (2) for the material and an element (4) movable relative to the conveyor for separating at least one component, wherein the movable element is provided with an adhering member (6) for at least one component which can be placed in at least two positions, wherein in the one position adhesion to this component takes place and in the other position release thereof occurs, this such that an enriched fraction results after one or more processings.

Description

A METHOD AND DEVICE FOR SEPARATING COMPONENTS FROM A COMPOSITE QUANTITY OF MATERIAL

The invention relates to a method and device for separating components from a composite quantity of material, said components having a high water rate and a low water rate respectively, for instance fat and meat components from slaughter waste meat, raisins and stones.

The method and device described in the preamble generally operates well when the components can be sorted into a particular property by means of a recognition or sensitivity. Separating components having a low and high water rate relatively, such as a meat mass composed for instance of fat and meat portions, this recognition has heretofore been found impossible.

The invention has.for its object to provide a method and device with which sorting of the said components such as fatty elements from a meat mass becomes possible in order to enrich the slaughter waste divided into small pieces with a larger meat percentage.

The method according to the invention is distin¬ guished in that components are transported along a carrier having a cold surface, sufficient to freeze the water content of the one component having a high water rate, to adhering said one component and to move it away from the other non-adhered component with the low water rate.

Due to the adhering member sensitive to the one component, a separation can now be accomplished with otherwise simple transporting means.

A device for carrying out the method is provided with a conveyor for the material and an element movable relative to the conveyor for separating at least one component, wherein the movable element is provided with an adhering member for at least one component which can be placed in at least two positions, wherein in the one position adhesion to this component takes place and in the other position release thereof occurs. In one embodiment the element is thus provided with at least one plate-like member which can be displaced from one position close to the conveyor to another position and vice-versa, and cooling means making contact with the plate-like member for the purpose of cooling the surface of the plate-like member in the said one position to below freezing point in addition to releasing means co-acting with the plate-like member for releasing the adhesion.

Owing to the use of the coolable plate-like member it is now possible at a sufficiently low temperature to freeze the meat directly onto the cooled plate, this sooner than the fat elements. When the mixture is supplied to the plate-like member the meat components will therefore remain adhered and the fatty components will not be picked up, whereby a separating or sorting becomes possible.

In one embodiment the plate-like member is a metal wall which is part of a chamber which is provided with a connecting stub for a cooling medium such as supercooled brine or liquid nitrogen. Brining liquid is recommended here with respect to safety requirements and hygiene standards in the food processing industry. The plate-like member can be brought herewith to a sufficiently low temperature.

According to a further development the plate-like member can be rapidly heated by connecting same to an electrical heating circuit whereby the adhesion between the meat components and the plate is broken, whereby separation can take place.

It is recommended to have sorting take place continuously, for which purpose the conveyor can be embodied as an endless conveyor, for instance an endless belt, on which the meat material can be supplied continuously. By guiding the plate-like member for instance according to a closed path along the carrying surface of the conveyor, a quantity of meat can be removed each time and the fatty component further discharged on the conveyor.

In preference the plate-like members are arranged in the jacket of a drum, wherein a cooling chamber can be arranged under the plate-like member. Above mentioned and other features of the invention will become clear from the figure description hereinafter of two embodiments. In the drawing: fig. 1 shows a perspective top view of a first embodiment, fig. 2 shows a section on larger scale of a detail of the plate-like member having cooling means arranged thereunder in the form of a chamber, as seen along the arrow II-II in fig. 1, fig. 3 shows a perspective view corresponding with fig. 1 of a second embodiment, fig. 4 is a perspective rear view of an alternative embodiment of the device according to fig. 1. Designated in fig. l with the numeral 1 is a conveyor which is embodied ^'here as an endless belt 2 which is trained round two reversing rollers 3, at least one of which reversing rollers is driven by a drive means (not shown) . The driving is such that the upper part of the endless belt moves in the direction of the arrow PI. Above the belt a drum 4 is placed rotatably on a horizontal axis A-A. This drum 4 is provided for this purpose with two shaft stubs 5 arranged on either side and rotatably mounted, wherein one of the stubs is likewise driven by a drive means (not shown) . Driving takes place in the direction of arrow P2. Arranged joining together along the peripheral surface of the drum is a number of plate-like members 6 which are mutually separated by a partition 7. Thus is created a circle of plate-like members 6 which each form the outer surface of a chamber arranged under these plate-like members 6, the cross section of which is shown in detail in fig. 2. The chamber is formed by a box-like element 8, this such that a closed chamber results. The space of the chamber is provided with a connecting stub (not shown) , this such that a coolant can flow into the chamber. This coolant can for instance be liquid nitrogen, carbon dioxide, ammonia or supercooled brining liquid so that a temperature well below the freezing point of water can be realized and the surface of the plate-like member 6 therefore acquires a correspondingly low temperature. The temperature range preferably lies between -10 and -40°C.

According to the invention each plate-like member 6 is further embodied with a contact element 10 which, at a determined position along the path of movement of the plate¬ like members, comes into contact with an electrical contact 11, see top left in fig. 1, which contact is arranged on a support 12 of the main frame. The drum itself is connected via a brushing contact 13 to the other contact of the electrical circuit (not shown) , this such that, when the electrical circuit between contact 11 and contact 10 is closed, an electric heating current is effected through the plate-like member 6 whereby the temperature can be increased briefly to above the freezing point of water. Placed on the front side of drum 4 is a collecting chute 14, the sloping bottom 15 of which leads to a discharge chute 16.

A supply hopper 20 is arranged on the front side of the conveyor 1 for the material for separating, for instance waste meat in the form of blocks which consist on the one hand of meat and on the other of fat and mixtures thereof. The outlet opening of supply hopper 20 lies above the upper part of belt 2.

Placed at a distance from this outlet opening is a buffer plate 21, the bottom edge of which connects onto the upper surface of the upper part of the belt 2, and which bottom edge is locally recessed to form a gate 22. A single layer of the material blocks or particles for processing is thus guided along the bottom side of the drum 4 when the belt is driven in the direction of the arrow PI.

It will be apparent from the above that when coolant is fed into the chambers of the elements 6, 8, the plate-like member 6 is brought below freezing temperature, whereby the water in the meat blocks freezes and the meat block will adhere fixedly to the surface of the plate-like member 6. The fat blocks do not undergo freezing so that they remain lying on the upper part of belt 2. The frozen blocks are thus carried along with the drum and guided beyond the topmost point of drum 4. When the electrical circuit is closed the surface of the plate-like member 6 is heated, whereby the meat blocks can drop down from the drum into the discharge chute 15, 16. The greater the percentage of meat in the mixed blocks of meat/fat, the sooner they will adhere to the drum, whereby a product enriched in meat component will eventually arrive at the discharge chute 16. The excess fat blocks will disappear into the collecting bin 25 at the end of the reversing roller of belt 2.

It is noted that the peripheral speed of the drum can differ from that of the conveyor belt so that during passage along the bottom of the drum the blocks undergo a rolling movement, whereby a meat portion will more quickly come into contact with the plate-like member.

The procedure as described above can be repeated a number of times so that increasingly "richer" constituents are separated out. The blocks can in the meantime be further reduced in size. Fig. 3 shows an alternative embodiment to that of fig. 1, wherein however the same reference numerals are used for the same components.

The most important difference can be seen in the form and placing of the drum 4, which is rotatable on an axis B-B parallel to the upper part of belt 2. The axis B-B is located behind the rear reversing roller 3 of the belt and close thereto such that the outer surface of the drum lies a layer thickness of the material particles for separating from the reversing roller 3. The drum is here not sub-divided into chambers but has a closed annular chamber. The annular chamber can here also be supplied with a coolant, as discussed above, but can also be filled beforehand with solid C0₂.

All material blocks fall into the gap between the drum 4 and the reversing edge of belt 2, wherein the meat portions will adhere to the cold surface of drum 4 and the fatty portions fall downward through the gap. A collecting bin 25 for the fat component blocks is arranged under the gap, while at the rear of the drum 4, where instead of a heating element a scraper tool 30 is arranged, the meat components are released from the drum surface 4 and will drop downward into the collecting bin 16' for the enriched meat mass.

Fig. 4 is a rear view of the embodiment according to fig. 1, with the difference that a resisting member 30 is arranged close to the rising part of drum 4. The resisting member is here embodied as a compliant or flexible strip which is fixed to the frame, for instance 12, in a manner not further shown. This member 30 does not allow through poorly adhered blocks and "sweeps" them off the surface of the drum 4. The poorly adhering particles are mainly blocks with a high fat constituent which fall together with the blocks on conveyor 1 into the collecting bin 25.

Within the scope of the invention embodiments other than as described above are possible. The plate surface does not for instance have to be cooled from inside, but the outer surface can also be sprayed with coolant. Releasing of the adhered blocks can also take place pneumatically, for instance with an air jet as scraper member placed along the periphery of the drum.

The invention is not limited to the above described embodiment.

Claims

1. A method for separating components from a composite quantity of material, said components having a high water rate and a low water rate respectively, for instance fat and meat components from slaughter waste meat, raisins and stones, etc., characterized in that the components are transported along a carrier having a cold surface, sufficient to freeze the water content of the one component having a high water rate, to adhering said one component and to move it away from the other non-adhered component with the low water rate.

2. A device for carrying out the method according to claim 1, being provided with a conveyor for the material and an element movable relative to the conveyor for separating at least one component, characterized in that the movable element is provided with an adhering member for at least one component which can be placed in at least two positions, wherein in the one position adhesion to this component takes place and in the other position release thereof occurs.

3. Device as claimed in claim 2, characterized in that the element is provided with at least one plate-like member which can be displaced from one position close to the conveyor to another position and vice-versa.

4. Device as claimed in claim 3, characterized in that cooling means making contact with the plate-like member are arranged for the purpose of cooling the surface of the plate-like member in the said one position to below freezing point in addition to releasing means co-acting with the plate-like member for releasing the adhesion.

5. Device as claimed in claim 4, characterized in that the releasing means are heating means for bringing the surface of the plate-like member above freezing point when it is lying in the other position.

6. Device as claimed in claims 4 and 5, characterized in that the plate-like member is a metal wall of a chamber which is provided with a connecting stub for a coolant such as brining liquid, liquid nitrogen or ammonia.

7. Device as claimed in claims 2-6, characterized in that the metal wall is provided with terminals for an electrical heating circuit.

8. Device as claimed in claims 2 and 4, characterized in that as releasing means a scraper member is arranged which comes into contact with the plate-like member when it lies in the other position.

9. Device as claimed in claims 2-8, characterized in that a jet nozzle directed onto the plate-like member is arranged for a cooloant such as liquid nitrogen or carbon dioxide.

10. Device as claimed in claims 2-9, characterized in that the separating element is a drum rotatable on an axis and along the periphery of which a number of plate-like members are arranged.

11. Device as claimed in claim 10, characterized in that a chamber is placed in the drum under each plate- like member.

12. Device as claimed in claims 2-11, characterized in that the conveyor is an endless belt and the drum-shaped separating element is rotatable on a horizontal axis parallel to the surface of the conveyor.

13. Device as claimed in claim 12, characterized in that the conveyor is provided with a spreading member for distributing the material over the carrying surface of the belt.

14. Device as claimed in claim 13, characterized in that the drum is driven at a peripheral speed which differs from the transporting speed of the conveyor belt.

15. Device as claimed in any of the foregoing claims, characterized in that a resisting member (30) is arranged close to the surface for releasing poorly adhered components.

16. Device as claimed in claim 15, characterized in that the resisting member is embodied as a flexible strip, an edge of which is located at a miximum distance from the surface of the adhering member 4 which is smaller than the mean thickness of the components.