Device and method for processing composite materials containing fibers

Abstract

The invention relates to a device for processing composite materials containing fibers, in particular packaging materials containing fibers and in particular used beverage packagings. Said device comprises a double container, which comprises: an inner drum-like container having a hollow cylindrical drum body, which is closed by means of an end bottom at one of two end faces of the drum body and is open at an opposite end face of the drum body, wherein the drum body has screen holes at least on a section of the circumferential surface of the drum body, and wherein at least one baffle is provided at least on a section of the circumferential surface of the drum body and/or on the end bottom, and an outer container, which at least partially surrounds the drum body of the inner, drum-like container, such that an intermediate space is formed between the outer surface of the inner, drum-like container and the inner surface of the outer container, wherein the double container can be pivoted in the vertical plane.

Claims

1. An apparatus for processing composite materials containing fibers, having a dual tank the dual tank comprising an inner drum-like tank rotatable in at least one of its two peripheral directions and having a hollow cylindrical drum jacket which is closed at a face base at one of its two face ends and which is open at its oppositely disposed face end, wherein the drum jacket has screen holes at at least a section of its peripheral surface, and wherein at least one baffle is provided at at least one section of the peripheral surface of the drum jacket and/or on the face base; and an outer tank which at least partly surrounds the drum jacket of the inner drum-like tank such that an intermediate space is formed between the outer surface of the inner drum-like tank and the inner surface of the outer tank; and wherein the dual tank is pivotable in a vertical plane.

2. The apparatus in accordance with claim 1, wherein the inner drum-like tank is rotatable in at least one of its two peripheral directions at a speed which can be set step-wise.

3. The apparatus in accordance with claim 1, wherein the dual tank can be pivoted step-wise by an angle of 0 to 90 with respect to a horizontal plane; wherein the dual tank is supported on a pivotable rack.

4. The apparatus in accordance with claim 1, wherein at least one inwardly directed baffle is provided at the inner side of at least one section of the peripheral surface of the drum jacket and/or on the face base of the inner drum-like tank.

5. The apparatus in accordance with claim 1, wherein the at least one baffle is arranged at an inner side of a section of the peripheral surface of the drum jacket adjacent to the face base and/or on the face base.

6. The apparatus in accordance with claim 5, wherein the at least one baffle or, if more than one baffle is provided, at least some of the baffles is/are arranged at the inner side of a section of the peripheral surface of the drum jacket, with the section of the peripheral surface of the drum jacket, starting from the end provided with the face base, viewed along a central longitudinal axis of the drum jacket, extending over 0 to 50% of the longitudinal extent of the drum jacket periphery.

7. The apparatus in accordance with claim 1, wherein the at least one baffle has a wedge-shaped cross-section and a wedge tip, with the at least one baffle being divided into a first part and a second part by a straight line extending from the central longitudinal axis of the drum jacket in the radial direction through the wedge tip, wherein a first angle .sub.1 between the straight line extending in the radial direction through the wedge tip and the line bounding the first part of the baffle, starting from the wedge tip, differing from a second angle .sub.2 between the straight line extending in the radial direction through the wedge tip and a line bounding the second part of the baffle, starting from the wedge tip; and wherein the first angle .sub.1 amounts to between 45 and 165 and the second angle .sub.2 amounts to between 165 and 45.

8. The apparatus in accordance with claim 1, wherein the screen holes are arranged on a section of the peripheral surface of the drum jacket of the inner drum-like tank, with the section of the peripheral surface of the drum jacket, starting from the end provided with the face base, viewed along a longitudinal axis of the drum jacket, extending over 60 to 95% of a longitudinal extent of the drum jacket periphery.

9. The apparatus in accordance with claim 1, wherein, in addition to the screen holes arranged on the peripheral surface of the drum jacket of the inner tank, at least one or more further screen holes are arranged on the face base of the inner tank.

10. The apparatus in accordance with claim 1, wherein the outer tank surrounds the drum jacket of the inner drum-like tank, starting from the end provided with the face base, viewed along a longitudinal axis of the drum jacket, over the full area by at least 50%.

11. The apparatus in accordance with claim 1, wherein the outer tank is bounded by a torispherical head at its end facing the end face of the drum jacket of the inner drum-like tank provided with the face base.

12. The apparatus in accordance with claim 1, further comprising at least one deflection means that is provided at an inner surface of the inner drum-like tank, with the at least one deflection means being of spiral shape.

13. The apparatus of claim 1, wherein the dual tank can be pivoted step wise by an angle of 0 to 90 with respect to a horizontal plane; and wherein at least one inwardly directed baffle is provided at the inner side of the inner drum-like tank.

14. The apparatus of claim 1, wherein the dual tank is during operation of the apparatus pivotable in a vertical plane.

15. A plant for processing composite materials containing fibers, said plant comprising: an apparatus having a dual tank, the dual tank comprising an inner drum-like tank rotatable in at least one of its two peripheral directions and having a hollow cylindrical drum jacket which is closed at a face base at one of its two face ends and which is open at its oppositely disposed face end, wherein the drum jacket has screen holes at at least a section of its peripheral surface, and wherein at least one baffle is provided at at least one section of the peripheral surface of the drum jacket and/or on the face base; and an outer tank which at least partly surrounds the drum jacket of the inner drum-like tank such that an intermediate space is formed between the outer surface of the inner drum-like tank and the inner surface of the outer tank; and wherein the dual tank is pivotable in a vertical plane; a solid/liquid separation apparatus; and a press.

16. The plant in accordance with claim 15, wherein the solid/liquid separation apparatus is connected via a line to the intermediate space of the dual tank of the apparatus and the solid/liquid separation apparatus is a thickener, a forming board or a screen; and wherein a liquid return line leads from the solid/liquid separation apparatus into the hollow cylindrical drum jacket of the inner drum-like tank.

17. The plant in accordance with claim 15, further comprising a dissolved air flotation device, a centrifuge device or a sedimentation device which is connected via a liquid line to the solid/liquid separation apparatus.

18. A method of processing composite materials containing fibers, said method comprising the following steps: a) pivoting a dual tank of an apparatus having the dual tank, the dual tank comprising: an inner drum-like tank rotatable in at least one of its two peripheral directions and having a hollow cylindrical drum jacket which is closed at a face base at one of its two face ends and which is open at its oppositely disposed face end, wherein the drum jacket has screen holes at at least a section of its peripheral surface, and wherein at least one baffle is provided at at least one section of the peripheral surface of the drum jacket and/or on the face base; and an outer tank which at least partly surrounds the drum jacket of the inner drum-like tank such that an intermediate space is formed between the outer surface of the inner drum-like tank and the inner surface of the outer tank; and wherein the dual tank is pivotable in a vertical plane; wherein the pivoting is performed such that the longitudinal axis of the drum-like tank adopts an angle .sub.1 of 5 to 90 with respect to the horizontal plane; b) introducing composite material containing fibers to be processed and water into the inner space of the hollow cylindrical drum jacket of the inner drum-like tank pivoted in the step a) and rotating the inner drum-like tank about one of its two peripheral directions for a duration in time t.sub.1; c) reducing the pivot angle of the dual tank to an angle .sub.2 with respect to the horizontal plane, where 0.sub.2<.sub.1, and rotating the inner drum-like tank about one of its two peripheral directions for a duration in time t.sub.2; d) optionally, increasing the pivot angle of the dual tank to an angle .sub.3 with respect to the horizontal plane, where .sub.2<.sub.390, introducing water into the hollow cylindrical drum jacket of the inner drum-like tank and rotating the inner drum-like tank about its longitudinal axis for a duration in time t.sub.3; e) reducing the pivot angle of the dual tank to an angle of 0 with respect to the horizontal plane and removing the remaining pulp from the hollow cylindrical drum jacket of the inner drum-like tank.

19. The method in accordance with claim 18, wherein the angle .sub.1 in the step a) and/or the angle .sub.3 in the step d) is/are set to a value of 5 to 60.

20. The method in accordance with claim 18, wherein a suspension containing fibers is removed from the intermediate space of the dual tank during the step b), and/or between the steps b) and c), and/or during the step c), and/or between the steps c) and d), and/or during the step d), and/or between the steps d) and e), and/or after step e), and the suspension containing fibers is led into a solid/liquid separation apparatus and is separated into a fraction rich in water and into a fraction rich in fibers.

21. The method in accordance with claim 18, wherein the remaining pulp removed in the step e) is led into a press and is dried there.

22. The method in accordance with claim 18, wherein composite material which contains fibers is introduced into the inner drum-like tank in the step b), with the packaging material comprising i) fiber material, ii) plastic, and optionally iii) aluminum foil.

Description

(1) There are shown:

(2) FIG. 1 a schematic perspective view of an apparatus for processing composite materials containing fibers in accordance with an embodiment of the present invention;

(3) FIG. 2 a longitudinal sectional view of the apparatus shown in FIG. 1;

(4) FIG. 3 a cross-sectional view of the apparatus shown in FIGS. 1 and 2 along the sectional plane A-A shown in FIG. 2; and

(5) FIG. 4 a schematic view of a plant for processing composite materials containing fibers in accordance with an embodiment of the present invention.

(6) The apparatus 10 shown in FIGS. 1 to 3 for processing composite materials containing fibers comprises a dual tank 12 which comprises an inner drum-like tank 14 and an outer tank 16.

(7) As can in particular be seen from FIG. 2, the inner drum-like tank 14 is hollow cylindrical and comprises a hollow cylindrical drum jacket 18 which is closed by a face base 20 at one of its two face ends and is open at its oppositely disposed face end. In this respect, the drum jacket 18 has at its end adjacent to the face base 20 a section at which a plurality of baffles 22, 22 are arranged at the inner side of the peripheral surface of the drum jacket 18 which extend in the longitudinal direction of the drum jacket 18, and indeed starting from the face base, over approximately 40% of the length of the drum jacket 18, i.e. the baffles 22, 22 extendstarting from the end provided with the face base 20, viewed in the longitudinal axis of the drum jacket 18over 5 to 35% of the elongate extent of the drum jacket 18. As shown in FIG. 3, four baffles 22, 22 are provided in this section which are distributed evenly over the inner surface of the drum jacket 18. In this respect, the individual baffles 22, 22 have an asymmetrical cross-section. The baffles 22, 22 specifically have a wedge-shaped cross-section which is divided into two parts 28, 30 by the straight line extending from the central longitudinal axis 26 of the drum jacket 18 in the radial direction through the wedge tip 27, wherein the first angle .sub.1 between the straight line extending from the central longitudinal axis 26 of the drum jacket 18 in the radial direction through the wedge tip and the line bounding the first part 28 of the baffle 22, starting from the wedge tip, differs from the second angle .sub.2 between the straight line extending from the central longitudinal axis 26 of the drum jacket 18 in the radial direction through the wedge tip and the line bounding the second part 30 of the baffle 22, starting from the wedge tip. It is thereby achieved that, in dependence on the direction of rotation of the inner tank 14, different mechanical stresses can be exerted on the mixture contained therein. In this respect, the baffles 22, 22 have a height h of 5 cm, with the height h being determined from the wedge tip up to the point disposed perpendicular thereunder on the peripheral surface of the drum jacket 18. At its face base 20, the inner tank 14 is connected to a rotatable axle and to a rotating motor via which the inner tank can be rotated step-wise in both peripheral directions of the inner tank 14.

(8) In addition, the drum jacket 18 has at its end disposed opposite the face base 20 a section at which a plurality of screen holes 24 are arranged in the peripheral surface of the drum jacket 18 which extendstarting from the end provided with the face base 20, viewed in the longitudinal axis of the drum jacket 18over 50 to 80% of the longitudinal extent of the drum jacket periphery. In this respect, the individual screen holes 24 are evenly distributed over this section of the peripheral surface of the drum jacket 18 and each have a circular cross-section which is dimensioned with respect to its diameter such that the fraction rich in fibers can pass through the screen holes 24, but not the pulp of fiber-free residual material such as plastic and, optionally, metal formed in the inner tank 14.

(9) In addition, the drum jacket 18 has at its inner surface a deflection means 23 which is of spiral shape and which extends over almost the total length of the drum-like tank 18.

(10) The outer tank 16 has the shape of an asymmetrical truncated cone, wherein the upper half of the peripheral surface of the asymmetrical truncated cone has an angle .sub.1 of approximately 90 to the base surface of the asymmetrical truncated cone and the lower half of the peripheral surface of the asymmetrical truncated cone has an angle .sub.2 of approximately 70 to the base surface of the asymmetrical truncated cone.

(11) In this respect, the outer tank 16 is arranged such that it surrounds the drum jacket 18 of the inner tank 14 over the full area by approximately 80%, starting from the end provided with the face base 20, viewed in the longitudinal axis of the drum jacket 18. At its end facing the end of the drum jacket 18 of the inner drum-like tank 14 provided with the face base 20, the outer tank 16 is bounded by a torispherical head 33.

(12) The outer tank 16 is furthermore arranged such that an intermediate space 34 is formed between the outer surface of the inner tank 14 and the inner surface of the outer tank 16.

(13) In accordance with the invention, the dual tank 12 is pivotable in the vertical plane. This is achieved in the embodiment shown in FIGS. 1 to 3 in that the dual tank 12 is supported on a pivotable rack 36. In this respect, the rack 36 has two arms 38 which extend in parallel with the longitudinal direction of the outer tank 16. At the end disposed opposite the face base 20 of the inner tank 14, the two arms 38 are connected via a cross-beam 40 on which the end of the inner tank 14 disposed opposite the face base 20 lies. At the end disposed opposite this cross-beam 40, the arms 38 of the rack are likewise connected by a cross-beam 42 which is connected to a pivot mechanism 44 via which the pivot angle of the dual tank 12 can be set.

(14) The plant 46 shown in FIG. 4 for processing composite materials containing fibers comprises an apparatus 10 as shown in FIGS. 1 to 3 and configured as described above, a solid/liquid separation apparatus 48 in the form of a disk thickener and a press 50 in the form of a screw press.

(15) In this respect, the solid/liquid separation apparatus 48 is connected via a line 52 to the intermediate space 34 of the dual tank 12 of the apparatus 10, wherein the solid/liquid separation apparatus 48 is supplied continuously or lot-wise via the line 52 from the intermediate space 34 of the dual tank 12 to the fraction rich in fiber removed from the apparatus 10. The fraction rich in fiber is separated in the solid/liquid separation apparatus 48 into water and into a thickened suspension rich in fibers, wherein the water is led back from the solid/liquid separating deice 48 into the hollow cylindrical drum jacket 18 of the inner drum-like tank 14 via a liquid return line 54, and indeed together with fresh water which is supplied via the line 54. In contrast, the thickened suspension rich in fibers is guided via a fiber removal line 56 as a recyclable fraction 1 for reuse e.g. in a paper-making factory.

(16) The filtrate of the solid/liquid separation apparatus 48 is guided via the liquid line 60 to a dissolved air filtration device 58 and is further purified there so that water having fresh water quality is removed from the dissolved air filtration device 58 and is returned into the apparatus 10 via the fresh water return line 62. The consumption of fresh water supplied via the line 54 can thereby be substantially reduced, which results in significant cost savings.

(17) At the end of the process, a pulp containing plastic and, optionally, metal is led off from the inner space of the inner drum-like tank 14 and is led via the line 52 into the screw press 50 and is dried to form the recyclable fraction 2 containing plastic.

(18) In addition, the plant 46 can comprise a bypass line 64 via which washing water removed directly from the intermediate space 34 of the apparatus 10, i.e. without running through the solid/liquid separation apparatus 48, can be supplied into the dissolved air flotation device 34 for purification. Such a bypass line 64 is in particular sensible when a pre-purification of the starting material such as described below should take place in the apparatus 10.

(19) On the operation of the plant 46, the dual tank 12 is first pivoted upwardly with the end of the inner tank 14 disposed opposite the end provided with the face base 20 such that the longitudinal axis of the drum-like tank adopts an angle .sub.1 of 5 to 90 with respect to the horizontal plane. The composite material containing fibers to be processed and a lot of water are then poured into the inner space of the hollow cylindrical drum jacket 18 of the inner tank 14 pivoted in the step a) and the composite material containing fibers is pre-purified and in this respect in particular liberated from fat and milk residues. For this purpose, the inner tank 14 is first slowly rotated in one of its two peripheral directions and the washing water which has flowed during the rotation over the screen holes 24 and/or over screen holes (not shown) provided at the face base 20 of the inner tank 20 into the intermediate space 34 of the dual tank 12 is then removed from the intermediate space 34 and is directly supplied via the bypass line 64 to the dissolved air filtration device 58 for purification. The purified water is then returned into the apparatus 10 via the fresh water return line 62.

(20) The inner tank 14 is subsequently rotated about one of its two peripheral directions for a duration in time t.sub.1. On the rotation, the water is intensely mixed with the composite material containing fibers to be processed and is mechanically strained by the baffles 22, 22, which promotes the dissolving of the composite material containing fibers into its components of fiber material, plastic and, optionally, metal. At the same time, any remaining organic contaminants are flushed out of the composite material. After this dissolving step, the pivot angle of the dual tank 12 is reduced to an angle .sub.2 with respect to the horizontal plane, where 0.sub.2<.sub.1, and the inner drum-like tank 14 is rotated about one of its two peripheral directions for a duration in time t.sub.2. In this respect, the baffles 22, 22 are at least partly exposed so that the mixture present in the inner space of the inner tank 14 is strained mechanically even more when it runs over the baffles 22, 22. In addition, the mixture present in the inner space of the inner tank 14 also contacts the section of the drum jacket 18 in which the screen holes 24 are provided due to the reduction of the pivot angle so that the fraction rich in fibers flows through the screen holes 34 into the intermediate space 34 and a pulp-like fraction rich in plastic and, optionally, rich in metal remains in the inner space of the inner tank 14.

(21) Subsequent to this, the pivot angle of the dual tank 12 can optionally again be increased, and indeed to an angle .sub.3 with respect to the horizontal plane, where .sub.2<.sub.390, before water for rinsing is introduced into the hollow cylindrical drum jacket 18 of the inner tank 14 and the inner tank is rotated about its longitudinal axis for a duration in time t.sub.3. Finally, after the duration in time t.sub.3, the pivot angle of the dual tank 12 is reduced to an angle of 0 with respect to the horizontal plane, that is the dual tank 12 is set horizontal and the remaining pulp is removed from the hollow cylindrical drum jacket 18 of the inner drum-like tank 14.

(22) The pulp and the fraction rich in fibers are then further processed in the press or in the thickener, such as has been described above.

REFERENCE NUMERAL LIST

(23) 10 apparatus for processing composite materials containing fibers 12 dual tank 14 inner drum-like tank 16 outer tank 18 hollow cylindrical drum jacket 20 face base 22, 22 baffle 24 screen hole 26 central longitudinal axis 27 wedge tip 28 first part of the screen hole 30 second part of the screen hole 32 deflection means 33 torispherical head 34 intermediate space 36 rack 38 rack arm 40 cross-beam 42 cross-beam 44 pivot mechanism 46 plant for processing composite materials containing fibers 48 solid/liquid separation apparatus/disk thickener 50 press/screw press 52, 52 line 54 liquid return line 54 fresh water supply line 56 fiber removal line 58 purification device/dissolved air filtration device 60 liquid line 62 fresh water return line 64 bypass line .sub.1 angle of the first part of the baffle .sub.2 angle of the second part of the baffle .sub.1 first angle of the outer tank configured as an asymmetrical truncated cone .sub.2 second angle of the outer tank configured as an asymmetrical truncated cone h height of the baffle D diameter of the drum jacket L length of the drum jacket