FI112516B - Grinder for grinding paper, cardboard or a moving web of a vegetative based fibrous raw material, has rollers or belts having a grinding surface coated with triboelectrically charged particles - Google Patents

Abstract

Grinder has rollers or belts (2,6,10) having a grinding surface in contact with a moving web, and rails (3,7,11) for moving the surface against the web direction and for adjusting the grinding force, the contact length and the web tension. The grinding surface is coated with triboelectrically charged particles having the same charge with the surface of the web. An Independent claim is also included for a process of grinding paper, cardboard or a similar continuous web of a fibrous raw material based on vegetable fibers, comprising conveying the web into a grinding apparatus with at least two grinding means, contacting the web with the grinding means so that the web tension can be adjusted as desired, adjusting the web tension so that a desired grinding force between the grinding means can be obtained, and thermally spraying triboelectrically charged particles on the grinding surface. The particles have the same charge with the surface to be ground.

Description

112516

Apparatus for grinding a web made of fibrous material

The present invention relates to an apparatus for grinding a continuous web made of paper, cardboard or vegetable fiber based fiber raw material according to the preamble of claim 1.

The invention also relates to a grinding device according to the preamble of claim 24.

The present invention relates to the treatment of paper and board and similar fiber-based webs, in particular their single or double-sided grinding. In our prior patent applications PCT / FI98 / 00341 and 980044, we have discussed the advantages of paper surface grinding, which can partially or completely replace surface calendering without compromising the strength properties of paper or board and without adversely affecting the quality of the guideline 20. . We have also shown that it is easier to attach different coating layers and,. ·. correspondingly that the coating plastic adheres more easily to the sanded material, ·. : surface than regular surface. This is due, among other things, to the removal of the fibrils from the fibers of the web surface, resulting in a very fine lint on the surface, which increases the bonding surface of the coating beads. Typical paper and board gin has a surface roughness of the order of 6 microns and can be sanded down to one micron. Because the inner structure of the paper is not ... compressed, its stiffness and strength properties are maintained and in some cases improved by up to 10%.

In principle, grinding can be done in several different ways: * '; a. Thus, an abrasive tape or an abrasive roll coated with abrasive material or an abrasive stone can be used. These 35 solutions are pure mechanical abrasives. It is also possible to grind various pigments which are used simultaneously or later for coating, for example by wedging the pigments at high speed against the paper web.

However, if you want to do a grinding so that the paper pin-5 at the same time so-called. calibrating is the tape or roller or grinder the only sensible option. The most preferred of these are abrasive roll or abrasive rolls.

The problem with known abrasives is their clogging of 10 wood resins with hemicellulose and possibly lignin combined with fine dust generated during grinding. In general, the abrasive pressure has been difficult to adjust in known devices, whereby too much grinding causes the surface temperature of the web to rise too high, resulting in the aforementioned clogging. Adjusting the grinding pressure is also important to accurately remove only a desired portion of the surface of the web without otherwise damaging the web.

It is an object of the present invention to overcome the drawbacks of the prior art and to provide a novel solution for grinding paper and board webs and the like, fiber-based continuous webs.

The invention is based on the idea that the grinding pressure can most easily be obtained by tightening the so-called. tensioning rolls, i.e., arranging a different tensioning angle between each abrasive roll and the paper, and adjusting the natural tension of the paper in addition to this. More series rolls or belt sanders' are still preferred because of the shape of a single grinding member; 30 and the calibration of the dimensions to a perfectly accurate dimension is difficult to achieve when the following grinding members are leveled; errors from the previous one.

A second and very significant finding of the invention is that the abrasive material, i.e. particles on the surface of the abrasive roll or belt, charges and charges triboelectrically released paper dust and fibers in the same charge or near the same charge as the fibers. The paper is always slightly negative when brushing, rubbing, and sanding. The opposite is the case with asbestos fibers, which are always strongly positively colored.

Alumina, beryllium, and many other alumina compounds are also slightly negatively charged. In our experiments, we have surprisingly found that, when this is the case, the abrasive dust and the fibers and fibrils released from the surface fly from the abrasive surface and the abrasive surface is not clogged at all when handling wood-free webs. This also applies to surface-bonded papers where known alkyl-texen dimers, alkyl-succinic anhydride and / or starch or cationic starch or a combination thereof are used as the surface-glue. All of these fly electrically charged off the surface, making it easy to vacuum with a vacuum cleaner near the grinding tent. Due to the electrical charge, the dust removal and removal is so strong that no environmental dust problems occur.

V 'For wood-free papers, triboelectric cleaning is complete alumina (Al2O3) or equivalent grinding surface.

* · '1 25 Also in papers made from partially woody ·, ”· fibers or pulp still containing residual lignins V: identical results were obtained. The sanding rollers were not soiled and the spaces between the sanding particles were not filled up in tests where · various papers were driven through the grinder for more than 40 · '_ · 1 ·' 30 km. It should be noted, however, that woody and resins and. . ·. for polymer-containing papers, other methods described in the present invention may be necessary.

The issue was also examined using colored papers, 112516 4

Because alumina has a hardness of 9 on the Mohs scale and, for example, beryllium (Al2Be3SiOi8) has a hardness of 8, beryl powder is a very suitable additive to alumina because it will wear unevenly and the grinding surface itself will sharpen itself as the wear progresses. Any softer additive or binder than alumina is suitable as long as it does not make the sanding layer conductive. Examples of such additives are titanium dioxide and iron oxide. Mixtures of these may also be used.

The abrasive surface of all abrasives is constantly slightly abrasive, whereby the abrasive surface absorbs less and less material from the abrasive. In this way, and according to the invention, it is essential to always move the worn grinding roller to the last one in the row of grinding rolls, when they are always used 2 to 8 in succession. The first two rollers, for example, abrade the surface of the paper the most and follow less and less. More than two rolls make the surface of the paper remove fibers and fibrils, after which the ground surface is freer from • fibers that have been separated from the surface than completely untreated raw paper. More than two sanding rollers. la sanded paper surface is even cleaner from rising fibers! and fibrils like normal surface glued paper.

25

The present invention therefore utilizes a device consisting of a plurality of abrasive elements deflected in the straight line of travel of the web, which can be brought into contact with the web. The grinding members are arranged so that they can be moved transversely to the web surface and toward the web. * away from the slide to adjust the tension of the web and thus the strength of its grinding. Preferably, each of the grinding members removes up to 1.5 microns of material from the surface of the web on average.

More specifically, the device according to the invention is essentially characterized in what is set forth in the characterizing parts of claims 1 and 24.

The invention provides considerable advantages. This allows the desired amount of material from its surface to be precisely separated from the paper-5 or board web. By adjusting the grinding pressure, the heat build up and clogging of the grinding wheels can be reduced. Controlling the rise of heat can prevent clogging of the sanding surface. The present invention also describes solutions for cleaning abrasive grinding pads which can quickly and efficiently remove material adhering to the abrasive surface, even continuously. The surface of the web is very smooth because the grinding members naturally remove material at the highest (thicker) points of the web. There are also 15 types of smoothing effect than in calendering, where the thicker sections of the web are squeezed and the web density at these points increases more than the thinner sections. Fibrillation of the web surface fibers improves the coating performance after grinding and binds the coating particles to the web by forming a larger 20 bonding surface.

BRIEF DESCRIPTION OF THE DRAWINGS In the following, the invention will be explored in more detail with reference to the accompanying drawings. ten.

25

Figure 1 is a side elevational view of a structure according to a first preferred embodiment of the device according to the invention.

Fig. 2 is also a side view of a structure according to another preferred embodiment of the device according to the invention.

. Fig. 3 is a side view of the principal structure of the sanding belt solution used as a grinding member.

35

Figure 4 shows one shape of the surface of the abrasive roll.

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Figure 5 shows one embodiment of a device for use as a grinding member.

In the following description, track tension refers to the tension caused by the friction formed by a grinding member, such as a roller, and not merely to the external track tension produced by the track-carrying members.

Figure 1 illustrates a basic embodiment of the invention in which the track 16 is ground in a roller mill 1-15. The device comprises a track mounted on the frame 1, the axes of the rolls 2, 4, 6, 8, 10 and 12 being mounted on rails 3, 5, 7, 9, 11 and 13, along which the rolls can be moved perpendicularly to the track and 15 away from it. The longitudinal axes of the rolls 2, 4, 6, 8, 10 and 12 are at least substantially parallel and in a substantially horizontal plane. In the case of Figure 1, the rolls are alternately disposed on opposite sides of the web. By moving the rolls perpendicularly to the track, the device 20 and at the same time the track tension can be adjusted. The displacement of the rolls may be accomplished by any known actuator and mechanism, such as air or liquid cylinders and electric motors. circuits. The direction of movement of the rolls need not be perpendicular! per track, but the rolls may be displaced, for example, by means of pivoting cranks or at an angle to the track.

V, The path of the web to be treated may deviate from the average straight line described in the example and may be implemented according to the abrasive devices used as desired. Roller movements can also be used to adjust the grinding distance,

I I

30 how much the track wraps around the track casing.

Fig. 2 shows a device arrangement similar to Fig. 1 with corresponding device parts (track 35, frame 21, track 22 -33). Again, the track tension can be adjusted by means of rollers 35.

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Instead of the rollers, grinding drums or belt sanding stations can also be used as grinding members in the devices of Figures 1 and 2. According to one embodiment, the grinding members comprise grinding rolls or drums 5 (e.g., 2, 6, 10; 22, 26, 30) arranged on one side of the web and adjustment rollers (4, 8, 12; 24, 12) arranged on the opposite side of the web. 28, 32).

Contrary to the solutions shown in the figures, the grinding wheels of the apparatus can also be implemented by arranging grinding rollers or drums on one side of the web and aligning them with press rolls on the opposite side of the web which are rotatable in the direction of travel of the web. Press rollers can reduce track tension and thus adjust the grinding result.

15

We have found that the grinding surface of the grinder remains clean under certain conditions and that, under certain conditions, the sanding material is blocked. This is one essential observation of the present device design and the invention. When grinding a pa-20 liner containing wood fibers, this fibrous material always contains resins and resins, depending on the type of wood, having a softening point or a melting point of between 65 and 75 ° C. When 'paper is pulp paper, that is, containing chemical cellulose', the paper is substantially free of resin and resin substances but to some extent lignin, which typically has a glass point of 124 ° C.

The above rollers are used to enable grinding to be carried out without locally exceeding the above-mentioned temperatures at the grinding site. So one sanding head off; up to about 1.5 microns of paper or fibrous web per sanding. In other words, when more is desired, more grinding heads or grinding rolls must be used respectively to grind the same side. To further ensure that, for example, the abrasive roller does not overheat, it is preferable to use either internal or external cooling (see below) to set the abrasive tool temperature to 1125168.

In the preferred embodiments shown in Figures 1 and 2, two or three rows of rolls are required to grind one surface of the paper, which can preferably rotate in the opposite direction to the direction of travel of the paper. Their rotational speed can be reversed when the track is driven through the grinder. A direction of rotation parallel to the path of the web may also be used.

10

For the abrasive apparatus according to the invention, it is preferable that the grinding wheel, i.e. the roller, drum or belt, rotates at a high speed relative to the abrasive fiber web, in order to minimize the surface pressure and prevent the device from tearing the intact fibers 15 out of the paper. The device should consume and fibrillate the fibers therein into tiny particles. The recovery of these is important and can be used either as a binder or for re-coating the same paper.

The abrasive members have an abrasive powder on their surface, preferably having a particle size of about 10 to 40 microns. As abrasives, for example, alumina, diamond, tungsten carbide, · silicon carbide, silicon nitride, tungsten nitride, boron nitride or boron carbide, chromium oxide, titanium oxide, chromium oxide may be used. titanium oxide alloys or mixtures containing any of the foregoing. The abrasive powder may be bonded to the abrasive, · '· surface by electrolytic or thermal spraying, or may be secured by gluing to a smooth layer, using a resin such as phenolic resin or v · 30 epoxy resin or a mixture thereof or a suitable rubber compound. The abrasive surface may also be the edge of the roll surface, even grinding or weaving paper, either simply as a properly shaped sharp, ·, edged, or by the shape of the edges of the edge. The edges can be made, for example, by milling grooves in the roll and then grinding roll 35 so that the edges of the heels between the grooves remain sharp. The roll surface can also be laser-fired with densely parallel grooves on the roll surface, leaving the edges of the burn mark rough. From such a surface, abrasion is obtained by grinding the surface of the roll to calibrate it, leaving a cutting jagged edge.

5

With the grinding device according to the invention, it is preferable that the speed of the grinding member, i.e. the roller or the belt, relative to the speed of the grinding web is such that the minimum speed difference is exceeded, whereby the grinding becomes discontinuous and no fibers are removed. This means that at high web speeds, the roller or grinding belt does not need to rotate at very high speed anymore because the web speed creates a large speed difference. The limitation to the speed of the grinding element itself is that the grinding surface against the track changes rapidly enough to allow the dust between 15 to escape and the cooling element to receive sufficient cooling air from the air stream. According to our observations, the speed difference is at least 200 m / min, preferably above 250 m / min. Higher speed difference is always more advantageous in terms of grinding result, but excessively high speed with eg sanding belt or sanding-20 blade causes eg vibration problems. Due to the ignition of the abrasive dust, the surface velocity of the abrasive should be kept high so that, regardless of the speed difference, the temperature at the abrasive does not rise above 100 ° C. This heat build naturally depends on the fiber web being sanded and the grinding pressure. 25 V * It is advantageous to cool each blade and blow or suck away any part of the abrasive dust that is not trapped in the grinding wheel. These two alternatives are illustrated in Figures 1 and 2. Figure 1 illustrates a case in which dust, · · 30 is sucked off under vacuum through vacuum connections 14, 15. Ku-,, ·. Section 2 shows how air can be blown by compressed air ···. stand towards the roll or drum to cool the surface of the roll and blow off the dust 34. Preferably, the powerful air stream to be blown is guided from the compressed air tube against the direction of rotation of the roll or drum.

112516 10

Holes may be formed on the surface of the grinding roller or drum, which are connected to a vacuum source and through which material to be removed from the grinding web can be removed. The grinding roller or drum may also advantageously be grooved so that only the ridges between the grooves have the part roughened by the grinding particles which performs the grinding and the intermediate groove serves as a collection point for the grinding dust. In this way, the abrasive surface will not get dirty and clogged as easily as with continuous grinding pin. The same groove system also functions as a cooling o-10 word. Figure 4 schematically shows one form of a grooved roll. In this solution, the surface of the roll has V-shaped grooves 47, between which there is an abrasive base 48, which may be coated with abrasive material or surface may be machined with an abrasive pattern.

15

A sanding belt may also be used as a grinding member (see Figure 3). Preferably, a metal strip 41 coated with abrasive particles is used which is rotated on rolls 42-44. To keep the tape clean, it can be fitted with at least 20 intermittent passages in a water bath 46 and an ultrasonic source 45 coupled to the water bath to direct radiation to the tape in the ultrasonic range.

; The abrasive roll or abrasive tape can be preferably formed by treating the metallic smooth polished or turned surface by electrolysis using the abrasive element as an anode. Various voltages and electrolyte compositions can be used to etch any surface of the desired pattern, the edges of which act as grinding edges. The electrolyzed surface may be tempered or the electrolytic treatment may be applied to the tempered surface.

; Electrolytic etching can be done, for example, in the following manner: Place stainless steel in an electrolyte containing 7 g / l soda and 2.5 g / l NaOH, using a distance of 15 mm between the anode and cathode and a large V. This provided a completely 112516 11 surface covering the original surface, filled with holes of 0.1-0.3 mm that are almost completely hemispherical and completely sharp-edged. In this method, it is essential that the electrolysis voltage is sufficiently high in order to initiate the uneven corrosion 5. The voltage must therefore be higher than when making a uniform electrolytic plating.

The electrolytically produced abrasive surface is particularly suited to abrasive the paper surface when, due to other abrasive effects or originally due to the properties of the paper, large fibers protrude from its surface, whereby abrasive surface dents break fibers like a razor blade rather than a sharp edge. Such a surface is particularly advantageous as the last abrasive surface because it effectively smoothes the surface 15, cutting off the fibers protruding from it.

According to the present invention, it can be ensured that the abrasive device cannot become clogged in the following way: As the abrasive surface begins to become obstructed at some point, this site generates more heat than usual and this obstruction site begins to spread and form e.g. a clogged parallel track that tends to spread.

,,; This is especially true for grinding wood-containing paper or paperboard blocks. Such clogging can be removed by abrasive blasting from the surface of the roll or tape with a strong light beam in the same way as, for example, US Polycon Industries removes paint from the surface of ships, for example, with powerful Xenon lamp flashes.

; 30 The abrasive surface can also be cleaned with a surface containing adhesive, which removes particles from the abrasive surface when the adhesive surface is pressed onto and removed from the abrasive surface. A surprising finding was that Al2C3 formed by abrasive particles; the surface itself did not adhere to the adhesive adhesive (e.g., styrene butadiene-based adhesive adhesive) and the adhesive adhesive did not adhere to the sanded abrasive tape.

112516 12

In the case where the abrasive element is a metal abrasive element (eg a roller or belt covered with abrasive material), the device may be provided with an inductive heater 5 for heating the abrasive element. In this case, a pneumatic tube is preferably connected to the device, by means of which a flow of air can be directed towards the heated grinding member in order to remove the loose dust during heating. The metallic surface, or the surface coated with an electrically conductive material such as chromium dioxide or titanium oxide, can be electrolytically cleaned by placing the electrolysis of the abrasive cathode into a cathode, whereby the gas formed by the cathode blows away the material accumulated therefrom.

L5 A laser beam can advantageously be used to monitor the condition of the grinding surface of the grinder. From a normal clean abrasive surface, the laser beam is reflected by a typical reflection angle of the abrasive particles into a certain reflection pattern, which depends on the abrasion particle roughness and quality of the particular abrasive particle. As soon as the grinder begins to clog or lose its abrasive properties for some other reason, the nature and amount of the reflection pattern changes so that it can be automatically detected immediately; claim and take remedial action, for example, to remove obstructive components from the abrasives, or replace the abrasive with a new one for another type of regeneration.

In order to enhance the sanding surface and to clean the sanding surface, a fine pigment may be added to the belt or sanding roller during grinding, or occasionally, which will bind the sanding dust to itself and keep the sanding surfaces clean. A laser or other light source whose reflection is used to monitor the purity of the abrasive surface must be below the wavelength of red light, otherwise the fine surface formed from particles of 10 to 30 microns does not provide sufficient scattering of control light. Surveillance with a laser beam formed of 112516 13 abrasive particles can only be done when the laser beam has a wavelength less than 2 times the particle size. In this case, the clogged surface and the clean surface give different reflections in the radial direction. In this case, the radius of the mouth must be nearly the same as the direction of the grinding surface. The direction of the beam should not deviate from the surface by more than 0.5 -3 degrees.

In addition to the above, the present invention has other embodiments.

The abrasive material need not necessarily be firmly bonded to the abrasive surface. Figure 5 shows an arrangement in which a magnetic abrasive is applied to the surface of the endless belt 50 during the abrasion of the magnet 49 during the abrasion process. The abrasive may be any sufficiently hard magnetic powder, for example iron, steel, magnetite, cobalt, nickel or a mixture of these or other known magnetic materials. The abrasive device comprises said belt, which may be made of metal or polymeric material or other suitable material from which a continuous endless belt can be made. The belt material should not be magnetic to prevent it from being magnetized completely.

The passage of the belt 50 is controlled by rollers 51, 52 and a magnet 49 is placed between the rollers 51, 52 '' · '25 inside the belt loop.

Outside the strap loop, a counter roll 53 is disposed opposite the magnet 49 and the web 16 to be treated is guided through the counter roll 53 of the traveling ground by guide rolls 54, 55. The roller 53 can be fitted so close to the belt 50 that the web 16 passing through it * 30 can be pressed against the belt. Belt *. * 50 can be rotated at the desired speed to the desired grinding speed; according to the weave, and the belt speed is preferably different from the speed of the web 16.

35 The abrasive dust and abrasive are collected in the movement direction of the belt 50 by a magnet-fitted vacuum cleaner 56 connected to a 112516 14 vacuum-forming blower 56 which supplies the abrasive and dust to the cyclone separator 58. Instead of the cyclone separator, magnetic separation or other suitable separation may be used. The abrasive is returned to the belt by blower 59 along line 60 and dust is removed through line 61. To enhance the abrasive collection, a magnet or a suitably directed air blast may be used at the separation point.

10 Grinding force and web tension can be set to a value suitable for grinding, for example, in the following ways. First, the grinding force is set by moving the grinding members and the track guiding members (4, 8, 12) in an initial position to create an initial tension in the web, then the final grinding force and track 15 are set by conventionally adjusting the web tension. On the other hand, the grinding force can be set by adjusting the track tension by means of the track pulling devices, usually by adjusting the track tension to an initial value, after which the final track tension and grinding force are adjusted by adjusting the position of the grinding members (2, 6, 10). Track tension can be measured with conventional tension measuring devices.

; ·· 'A pneumatic device may be provided on the opposite side of the grinding member to provide an additional pressure between the abrasive and the abrasive roller, i.e., the so-called. an air cushion that allows' · '' to adjust the grinding result regardless of track tension and · '' distance between the grinding element and the track to be sanded.

: 30, · · Note that the sanded surface can be polished with eg tape or brush polishes.

Claims (29)

Apparatus for treating paper, cardboard or a corresponding movable web (16) made of plant-fiber-based raw material, comprising: 5. a body (1) and - means arranged at the body (1) ( 2, 4, 6, 8, 10, 22) for controlling the movable web (16) along a designated web, characterized by 10 - at least two treatment means (2, 6, 10) comprising a grinding surface, which can be arranged against the surface of the movable web (16), and - means (3, 7, 11) for moving the at least one abrasive surface (2, 6, 10) against the movable web (16) for adjusting the abrasive strength between the web (16) and the abrasive surface, the contact distance between the abrasive and the web and the web tension. 2. Device according to claim 1, characterized in that it comprises several grinding means which deviate from it; The web can be contacted with the web and is arranged to be moved transversely in the distance to the surface of the web against the web and away from the web to control the web tension and thereby the abrasive strength directed towards the web. '1' 25 3. Apparatus according to claim 1, characterized in that the grinding means consist of successively arranged grinding rolls or drums or belt grinding stations. '; 4. Device according to claim 3, characterized in that the grinding means comprise grinding rolls or drums arranged alternately on both sides of the web. 5. Device according to claim 3, characterized in that the grinding means comprise grinding rollers or drums arranged on one side of the web and control rollers arranged on the opposite side of the web. Apparatus according to claim 3, characterized in that the grinding means comprise grinding rollers or drums arranged on one side of the web and pressing rollers which can be rotated in the direction of movement of the web, arranged on the opposite side of the web. Device according to any of claims 3-6, characterized in that at least the abrasive surfaces of the abrasive rolls or drums can be cooled. Device according to any of the preceding claims, characterized in that the abrasive means can be arranged to be pressed against the web in such a way that the surface of the abrasive means; temperature does not exceed a predetermined temperature limit, which, when grinding wood-containing webs, rises to preferably 65 ° C and grinding cellulose-containing webs preferably 124 ° C. * t Device according to any one of the preceding claims, characterized by a laser device, whereby a movable laser beam can be directed towards the abrasive surface of the abrasive means, and: on the basis of changes in the reflection pattern therefor:: ray can wear and / or obstruction of the abrasive surface be determined. Device according to any of the preceding claims, characterized in that the surface of the abrasive means exhibits an abrasive powder which, to its particle size, is up to 10 - 40 microns. 23 1 12516 11. Device according to claim 10, characterized in that the abrasive powder is attached to the abrasive surface by electrolytic or thermal spraying, or it is fixed by gluing as a uniform layer using resin, such as phenolic resin or epoxy resin or mixtures thereof, as adhesive. . 12. Apparatus according to claim 1, characterized in that the grinding means consists of a roller, the surface of which, for example, is formed by a laser beam (47) in the axial direction of the roller, the edges of the roller forming a grinding edge or a rough cutting edge. Device according to any one of the preceding claims, in which a grinding roller or drum is used as grinding means, characterized in that the heel of the grinding roller or drum has been formed, which is connected to a: source of suppression and via which the substance which is detached from the web, which is ground, can be removed. Apparatus according to any of the preceding claims, in which a grinding roller or drum is used as grinding means, characterized in that the surface of the drum or drum; 'Is provided with rafters, the rafters are arranged substantially; 25 perpendicular to the direction of movement of the web and on the axes of the catch are abrasive particles implanted in the surface for performing grinding. Apparatus according to any one of the preceding claims, in which a grinding roller or drum is used in such grinding means, characterized by a compressed air pipe directed at at least one drum or drum and by means of which such a strong air flow can be blown against the drum or drum. In the direction of rotation of the drum which cools down the roller and removes the dust that is stuck to the surface of the drum or drum. 16. Apparatus according to any of claims 1-11, characterized in that the grinding means is a metal band 10 coated with abrasive articles. Device according to Claim 15, characterized in that the band is at least occasionally arranged to run in a water bath and to the water bath is connected an ultrasonic source, whereby the ultrasonic region strain can be directed towards the band. Apparatus according to any of the preceding claims, wherein the grinding means is a grinding device made of metal, characterized by an inductive heater, by means of which the grinding means can be heated, and a compressed air pipe, whereby a air flow can be controlled against the heated) in the grinding means to remove the dust that is released during the heating. . ·· *, 25 19. Apparatus according to any of the preceding claims, characterized by a flash-1 light source, whereby strong flash light rays can be directed towards the abrasive surface to remove the substance stuck to the abrasive surface. Apparatus according to any of the preceding claims, characterized in that the abrasive articles are aluminum oxide, diamond, tungsten carbide, silicon carbide, silicon nitride, tungsten nitride, boron nitride, boron carbide, chromium oxide, titanium oxide, a titanium oxide mixture, containing two or more of these substances. 5 21. Device according to any one of claims 1-11, characterized in that the abrasive surface is made of metal and treated as anode in an electrolytic treatment with at least a high voltage, that an uneven corrosion of the surface 10 is started. Apparatus according to Claim 21, characterized in that at least one abrasive means, in particular the member which performs the last grinding, is constituted by an electrolytically produced abrasive member, the surface of which, like a shaver, cuts off the fibers that protrude from the surface being ground. Apparatus according to any one of the preceding claims, characterized by at least one abrasive surface comprising conductive material and an electrolysis device, to which the abrasive surface can be arranged as a cathode for cleaning: the surface by means of the gas bubbles which, during the electrolysis, emit at cathode. Apparatus for treating paper, cardboard or a corresponding movable web (16) made of plant-fiber-based raw material, said device comprising 25. a frame (1), and: - - means arranged at the frame (1) ( 2, 4, 6, 8, 10, 22) for controlling the moving web (16): along a defined web, characterized by at least two treatment means (2, 6, 10) comprising a grinding surface, which can be arranged against the surface of the movable web (16), and - means (3, 7, 11) for moving the at least one abrasive surface (2, 6, 10) towards the surface of the movable web (16) which is treated for adjusting the abrasive strength between the web and the abrasive surface, the contact distance between the abrasive member and the web, and the web tension, wherein the abrasive processing means are substantially coated with a material which, upon grinding, receives a triboelectric charge which is at least substantially similar to the charge of the plant fiber-based the material obtained. Device according to claim 24, characterized in that the abrasive treatment means are coated with alumina 15 or with such a blank. 26. Device according to claim 24 or 25, characterized in that the abrasive treatment means are coated with a mixture of alumina and another substance which is softer than alumina. 27. Apparatus according to claim 26, characterized in that the abrasive treatment means are coated with a mixture of alumina and beryll, a mixture of alumina and titanium dioxide and / or a mixture of alumina and iron oxide. :: 25 28. Apparatus according to any of the preceding claims, characterized in that on the opposite side of the grinding treatment means is a device using compressed air, which provides an air cushion between the material being ground and the grinding treatment means, with which the grinding result is adjustable independently of the web tension. and the distance where the abrasive processing means and the web being ground are in contact with each other. Device according to any one of the preceding claims, characterized in that the web being ground and the surface of the sanding treatment means can be caused to move in relation to each other at a speed difference of at least 200 m / min. I! IN