FI70935C - OVER ANCHORING FOER ATT SORTERA PAPPER - Google Patents

Description

\ * jg * r * \ rBl m ANNOUNCEMENT παλ 7 r • SäFff B ^ utläggningsskrift 7u v 55 c (45) tty. Pr jrt mo. ·. '; .lit 27 1 ,: 10-20 (51) Kv.lk.7int.c1. · D 21 B 1/08 (21) Patent application 1 - Patentansökning 773778 (22) Application date - Ansöknlngsdag 1 k. 12.77 (F ') (23) Start date - Glltighetsdag 1 ^ 4. 12.77 (41) Become Public - Blivit offentllg 30.06.78

National Board of Patents and Registration / 44) Date of issue and issue | - 10 07 86

Patent and registration authorities '' Ansbkan utlagd och utl.skrfften publlcerad (86) Kv. application - Int. trap (32) (33) (31) Privilege claimed - Begird priority 29 · 1 2.76 Canada (CA) 268802 (71) Reed Ltd., 1 * + 5 King Street West, Toronto, Ontario, Canada (CA) (72) Alexander Bialski, Lorettevi11 e, Quebec, Camillo Gentile, Mississauga,

Ontario, Ola Sepal], Quebec, Quebec, Canada (CA) (7 * 0 Antti Impola (5 * 0 Method and apparatus for sorting paper - Forwarding and sorting of paper)

The invention relates generally to the recovery of waste paper (for the purpose of its recovery) by means of the method and apparatus described below, which lead to overwhelming economic advantages compared with the previously known practice.

The recovery of waste paper now seems to be becoming increasingly important commercially. This means that the recovery of paper now seeks to go beyond what could previously be called the "basic" recovery, according to which the recovered product has been commercially acceptable only for inferior uses, e.g. for the manufacture of roofing felt, while the current the trend is to improve the quality of the recovered product so that it can be used more economically if possible.

It should be remembered that waste paper is often provided or available for recovery as blends, which may contain various components ranging from preferred chemical kraft papers to inferior newsprint papers, all of which are arbitrarily blended together as heterogeneous blends. In order to improve the quality and yield of paper recovered from such blends in qualitative terms, it is therefore first and foremost necessary to sort the blends into their respective components in order to treat them separately.

2,70935 The waste paper blends referred to herein are obtained from a variety of sources, but are not o-relevant to the present invention, as long as the paper obtained therefrom is dry so that its moisture content does not substantially exceed 60%, and the paper can be ground as follows.

One such source may be waste paper, which is thrown away in the offices on a daily basis and collected in the evenings by the cleaning staff of the office. Such waste paper may apparently contain two or more components, ranging in quality from first-class waste paper to low-grade newsprint. These different grades are thoroughly and unsorted mixed together, resulting in the above blends. Waste paper blends are usually obtained from other sources as such.

It is clear that when the yellow mixture described above is reused, the product resulting from this reuse cannot achieve a higher quality than its weakest component, despite the fact that the mixture may contain much finer grades of paper. Thus, the main use of the recovered paper product is limited to the lowest quality grades.

It is therefore a general object of the invention to provide an efficient method and apparatus for automatically sorting such paper blends and thus separating the various components of these blends for separate reuse. It must, of course, be borne in mind, however, that the overall quality of high-quality paper is not adversely affected in commercial terms by the small quantities of inferior paper that are randomly mixed with it.

The invention is based on the observation and the fact that paper of a certain quality can generally be distinguished from another quality on the basis of the difficulty or ease with which these grades can be comminuted, i.e. broken into pieces. Thus, papers made from mechanical pulp or wood chips, such as newsprint, are generally easier to grind than chemical pulp grades, such as kraft paper.

It is therefore a general object of the invention to provide efficient and economical methods and apparatus for selectively sorting an o-type paper blend of the type described so that the blend can be separated into its components based on the sensitivity with which these components can be broken down into paper quality.

5,70935

According to another idea of the invention, it is an object to provide methods and apparatus for applying forces or stresses to this paper in order to break the paper into pieces, and the related object is to recover the formed pieces pre-sorted and separated on the basis of their quality.

It is, of course, necessary to subject all the components of the paper mixture to the device according to the invention in such a way that the maximum production of the pieces of paper is achieved in a minimum time. In this case, however, the measures intended to subject the paper mixture to such treatment also apply crushing forces to the mixture, which is also within the scope of the invention.

The invention achieves the above and other objects by providing a method and apparatus for applying grinding forces to a described paper blend, wherein the blend is thoroughly mixed and subjected to substantially all of the blends, and also intentionally contributes more or less to the development of these forces. other forces are applied until at least one of the components of the mixture has been comminuted and removed from the mixture, after which, of course, the described treatment can be continued to grind one or more other components of the mixture.

The described comminution treatment is performed in a mill having a substantially closed space forming means and an impeller in this space, between which the paper is compressed, and where it is ground as described, the forces applied to the mixture being programmed as follows to grind the various components in turn. Due to their quality differences, some paper components grind more easily than others, and according to the invention, the comminuted pieces are recovered at one or more appropriate stages of the grinding process between the times when grinding of a particular paper grade is completed but before grinding of another paper grade begins. However, precise accuracy in this regard is not critical to the practice of the invention, and such accuracy is also likely to be difficult to achieve.

A selected embodiment of the invention with its elements, parts and principles will be explained in more detail below on the basis of the accompanying drawings.

Fig. 1 is a schematic isometric view of a mill from which some parts have been removed to show the structure of some of the interior parts of the mill shown as 70935. The figure shows the longitudinal dividing lines of the mill, in addition to which a planned addition is shown in broken lines.

Figure 2 shows a section taken at line 2-2 of Figure 1. Paper has been added to the mill to illustrate this operation.

Figure 3 shows an isometric view of a detail of the invention.

Figure h shows a few cross-sectional profiles of another part of the device according to the invention.

Figure 5 shows a schematic and isometric view of an embodiment of parts of a mill casing according to the invention.

The device illustrated in the drawing is intended to summarize the devices of the invention, while the following descriptions of the use and operation of the invention are intended to illustrate some typical methods.

As shown in the drawing, the invention realizes its object by applying forces to the paper mixture which will reduce the various components of the mixture into pieces. Because different components are differently sensitive to these grinding forces, one or more such components may, during normal processing, be almost completely divided into pieces before the other components even begin grinding, recovering the resulting pieces between these different grinding steps.

According to the general idea of the invention, the driving forces are programmed in such a way that, ideally, each different paper component in turn becomes relatively completely divided into pieces, whereby the pieces of each component are also recovered in turn. In practice, however, there will be some overlap between the comminution (and recovery) of "neighboring" components, which is thought to inevitably occur. The terms "complete" comminution and "complete" recovery used hereinafter therefore also mean such a virtually inevitable overlap.

The grinding treatment, which produces the forces by which the various components of the paper mixture are correspondingly comminuted, can be carried out in mill M, whereby all components of the mixture are simultaneously and indiscriminately subjected to these forces, and these components are gradually comminuted. The paper mixture is suitably mixed during these grinding treatments in such a way that all the components and parts of the mixture are certainly subjected to crushing forces, which in turn increase more or less as a result of the mixing or the mixing at least completes 5 ....... . 70935 these forces. ^ It should be emphasized here that the expression "mix" is used to refer to all operations carried out to turn or rotate the paper mixture in such a way that all parts of this mixture are subjected to crushing forces, the silver mixture being subjected to a wide range of mechanical operations, eg bending, braiding, creasing, whipping, massaging, friction, pulling, tearing, and probably other treatments »that work together to separate the components of the paper mixture and ultimately grind them.

However, one treatment that the invention seeks to avoid is chopping or cutting the paper, which should compromise the necessary selectivity of the invention with respect to the various components, and should further shorten the paper fibers and thus degrade the quality of the recovered paper.

The mill M shown schematically in Figure 1 and chosen as an example in this connection has an impeller 2 adapted to rotate in the mill casing 4 on a shaft 6 mounted at points 8, 8 on the sides 10, 10 of the casing 4. Reference numeral 12 denotes a motor which can be engage the shaft 6 to rotate the impeller 2 at the desired speed.

In this case, the impeller 2 is either partially or completely surrounded by a supporting screen mesh 14, the openings of which are dimensioned according to the size of the pieces of paper to be screened through it.

The screen net 14 is spaced from the impeller 2 so as to leave a space 16 for the paper mixture and the vanes 18. The vanes 18 extend radially outwards from the impeller and are arranged at suitable intervals along the circumference of this impeller to act as buckets which adhere to the paper mixture in space 16 and move it as the impeller 2 rotates, so that the paper is blended as described above In order to facilitate.

It is clear that several factors contribute more or less thoroughly to the rate and efficiency of paper comminution in mill M or by the influence of this mill.

Of these factors, the rotational speed of the impeller 2 and the length of time during which the paper is exposed to the grinding forces acting in the mill M are obviously important.

In addition, the width of the space 16 around the impeller 2, the amount of paper trapped in this space, the moisture content of this paper, the cross-sectional shape of the wings 18, their protrusion into the space 16, the quality of the paper and other such factors are further contributed to.

Appropriate balancing of these and other factors in order to achieve an optimal result in each of the various cases, of which balancing is referred to herein as "programming", ensures the most efficient and economical operation of the mill M.

In this context, it should be explained that the screen net 14 effectively solves the problem of creating a closed space for the impeller, and the screen network further has a plurality of openings through which the pieces of paper 20 comminuted by said forces can be removed from this space and recovered. The screen net 14 is apparently one of a number of perforated means that can be used to create a closed space around the impeller 2, and / or to facilitate the removal of the pieces 20.

For example, to understand the operation and performance of a mill M, it can be assumed that a given paper blend has three different components that differ in that they break into pieces in different ways due to the forces generated in the mill M, suitably programmed as intended.

When the grinding treatment is applied to this paper mixture, the first of its three components (which is thus most fractured by the comminuting forces) first begins to break, leaving the resulting pieces 20 through the screen mesh 14, as shown in Fig. 2. At a certain stage of the grinding treatment, which can be measured e.g. over time, it can be assumed that the first paper component is theoretically completely comminuted and recovered. In practice, however, programming must be limited to grinding only one grade of paper at a time in order to avoid deterioration of the recovered product due to scattered pieces of other grades of paper. In any case, the continuous grinding will then lead to the comminution of the second component, and once this has been completed and the pieces formed have been recovered, the paper remaining in the mill will apparently be the last component of the mixture. In practice, of course, one or more other components may be included in the mixture between the second and last recovery.

It may, of course, be the case that the second or some subsequent component requires a second programming of the forces required to grind it. In such a case, two obvious 7 70935 options are available, namely (a) either reprogram the forces to affect this second or later component in the same mill M, or (b) transfer the crushed paper from the mill Ma where the first component was processed to the second mill Mb , which is more suitably programmed for this second component.

Both of these alternatives are shown in Figure 1, in which the mill M is shown as an elongate machine and the vanes 18 are attached to the impeller 2 in a helically inclined manner, whereby as the impeller 2 rotates, the closed paper mixture between this impeller 2 and the screen 14 becomes mixed. , which is on the left in this figure, towards the other end.

According to Figure 1, this mill M is divided into three units Ma, Mb and Mc by two pairs of dashed lines to indicate discontinuities, indicating that the units Ma, Mb and Mc or any adjacent units can be separated from each other or combined into one unit. In practice, it is obvious that the corresponding units do not have to be placed side by side in the case that they are separate units.

The wings 18 may be helical, as shown in this figure, or they may be rectilinear as shown in Figure 3. Likewise, they can be continuous along the entire length of the impeller 2 or be separated from each other with gaps 22, so that the pins 24 attached to the other parts of the mill M can be positioned so as to pass through the slots 22 when the impeller 2 is rotated. paper through slots 22.

The wings 18 can have a wide variety of different shapes in cross-section, as shown by way of example in Figure 4. In this case, care must be taken to design these wings in such a way as to avoid cutting the paper.

Apparently, the mill M can be formed in many different ways according to the invention, so that it is most suitable for grinding the paper which may be processed in this mill.

The structure of the wings has already been referred to above. In addition, the force with which the paper rubs against the screen net 14 can be influenced by varying the speed of rotation of the impeller 2, which can be done in any known manner or by using known controls schematically illustrated by the block element 25 of Figure 1.

The paper mixture can be fed to the mill M, e.g. by means of a screw feeder 26a, which delivers the mixture to the collecting space 28 above the impeller 2. The feed rate is one of the factors determining the efficiency of the mill, as it affects the amount of paper 8 70935 sealed in space 16.

Yet another important factor is the length of time the paper stays in the mill M.

The importance of any single factor obviously depends on ·· other factors as well.

Thus, for example, the time factor can be shortened or extended by varying the impeller speed or feed rate. It is also possible to vary the paper feed speed to the mill il, in which case other factors must be suitably compensated.

Balancing all of these factors according to the particular paper being chopped and its moisture content is commonly referred to herein as programming. Ideally, the invention is intended to be limited to "dry" paper having a said moisture content of not more than 60%.

In accordance with the invention, the paper mixture to be sorted is fed to a hopper H (Fig. 1), from which a screw conveyor 26 transfers the mixture to a collection space 28 where the impellers 18 of the rotating impeller 2 grip the mixture and pull it down into a space 16. grinds into pieces and these pieces exit through a screen mesh 14, the loop size of which is suitably sized to screen these pieces through this mesh.

Obviously, those components of the mixture that are most easily broken must first be removed, as mentioned above, while the other components are then comminuted and removed alternately in the same manner as the grinding of the residue is continued using either the same or alternative programming.

The described structure of the mill K is limited to only one basic structure, because of course there can be numerous structural embodiments to which the idea of the invention can be successfully applied.

Thus, it is to be understood that the objects of the invention are achieved by mixing relatively dry paper between the impeller 2 and a closing means, such as a screen net 14, with a mesh size large enough to screen through the loops 20 but not so small that these pieces remain closed space for further reduction. In this embodiment, the mixing is performed in a known and obvious manner by rotating the impeller 2 inside the fixed screen network 14. However, under suitable conditions, obvious alternatives may be used: - 9 70935 to pull the screen 14 back and forth instead of rotating the impeller, or in addition to this, especially if the screen 14 extends around the entire impeller 2 so as to enclose both the collection space 28 that the state 16, as shown in Fig. 2, is shown in broken lines.

The vanes 18 are the optional elements by means of which the impeller 2 can capture the paper in the collection space 28 and move it to the space 16, as well as mix the paper and rub it against the screen net 14. However, there is a wide variety of cross-sectional profiles of the wings 18, as seen in Figure 4, and there is also some choice in their general shape, as exemplified: the discontinuous shape shown in Figure 5 and the sinusoidal or helical shape shown in Figure 1, which tends to to carry it forward inside the surrounding screen net 14 in the longitudinal direction of the impeller 2 as this wheel rotates.

It should be clear and readily understood that the paper can be led to the collection space 28 on the one hand and passed through the mill M in many different ways, of which the screw conveyor 26 and the helical vanes 18 are shown as pearl examples in Figure 1.

Thus, in Fig. 1, the funnel H is shown (in dashed lines) repositioned to the left in this figure, it being clear that the screw conveyor 26 can be considerably shortened from its described length.

Bringing the paper from left to right in the mill M as described can be achieved or facilitated by placing the inclined deflections 30 attached to the screen mesh 14 more or less as shown in Figure 3. In fact, the paper can also be made to proceed using any of a number of means known in the art.

The invention is formed within the framework of these parameters, whereby, of course, the special means by which the invention is applied are factors which generally affect the programming of the final equipment.

To avoid misunderstandings, it should be borne in mind that although there has been talk of complete comminution and complete assembly of the formed pieces, this is in fact a rather impractical limitation, as in many cases a certain type of paper is shredded into different types of mixed waste or pieces. previous. Although the relevant programming will limit these scatterplots to tolerable limits so that their effect cannot be disregarded 10 709 3 5, the term "complete" as used herein in connection with comminution and recovery does not imply any absolute perfection, nor should it be construed as such.

Again, it should be borne in mind that the paper blends of the invention may come from a variety of sources, so it is to be understood that they may contain substances other than paper, so it is further understood that such other substances which cannot be shredded must be removed from the enclosure. after the other components of the mixture have been comminuted.

The real idea of the invention is thus clear from the following claims.

Claims (19)

A method for treating a dry paper mixture by separating and recovering at least one of its components from the remaining part of the mixture, characterized in that - all components of the mixture are simultaneously subjected to a grinding treatment, - forces are applied to this mixture, comprising rubbing the mixture against the surface causing a continuous comminution of said components, and - recovering pieces of paper formed in at least one step of this grinding treatment. A method according to claim 1, characterized in that the grinding treatment comprises mixing the mixture to subject all parts thereof to grinding forces and to develop and apply at least a part of these forces. Process according to Claim 2, characterized in that the mixing of the mixture is carried out in a closed state. A method according to claim 2, characterized in that the mixing of the mixture is carried out in a closed state with a plurality of openings through which said pieces are recovered, and said forces are programmed to grind substantially one component completely and grind it into pieces passing through these openings. through which the pieces are recovered before comminuting the remaining portion of the mixture. A method according to claim 4, characterized in that the mixing of the paper is performed between an impeller and a screen-closing means, said means having said openings, wherein at least one of these parts is rotated to effect mixing. Method according to Claim 3, characterized in that the impeller is rotated. Paper mill (M) for carrying out a method according to one or more of the preceding claims, characterized in that it has - an elongate impeller (2), - means (14) spaced from this impeller for forming a closed space around the impeller, - means (H) ) for feeding the paper mixture into the space between the impeller and the closing means, 1 z 70935 - means (12) for causing a relative rotation between the impeller and the closing means for mixing the paper mixture in this state, and - impeller radially projecting vanes (18) against during this rotation to grind at least one component of the paper mixture, wherein the space between the closed space and the impeller forms at least one free path for the mixture to be rubbed therein. Paper mill (M) according to Claim 7, characterized in that the impeller (2) is rotatable. Paper mill (M) according to claim 7, characterized in that the means (14) forming the closed space is perforated and forms openings for removing pieces of paper as they are formed. Paper mill according to Claim 7, characterized in that the means (14) forming the closed space are made of a screen. Paper mill according to Claim 7, characterized in that the vanes (18) are helical and tend to cause the paper mixture to travel in the longitudinal direction of the impeller (2) as the impeller rotates. 11 PATENT CLAIMS 70935 Paper mill according to Claim 7, characterized in that the vanes (18) have slots (22) and the mill has fixed pins (24) which pass through the slots as the impeller rotates. A paper mill according to claim 7, characterized in that it has a collector space (28) above the impeller (2), a feed device (26) for introducing the paper mixture into this collector space so that the impeller captures the mixture and moves it to a closed space. Paper mill according to Claim 13, characterized in that the means (14) formed by the closed space are made of a net. Paper mill according to Claim 14, characterized in that the net forming the space also encloses the collector space (28). Paper mill according to Claim 14, characterized in that the feed device (26) for transferring the paper mixture to the collecting space (28) is a screw conveyor (26). 13 70935 Paper mill according to claim 16, characterized in that it has a mill casing (4) with a funnel (H) for the paper mixture, and said screw conveyor (26) operates between the funnel and the collector space (28). Paper mill according to Claim 16, characterized in that the impeller blades (18) have a helical shape and tend to cause the paper mixture to travel in the longitudinal direction of the impeller (2) as this impeller rotates. Paper mill according to Claim 16, characterized in that the impeller blades (18) have slots (22) and the mill has fixed pins (24) which pass through these slots as the impeller (2) rotates. % 14 709 35 PATENTKRAV 'v ^ U