Feeding device for a high-pressure roller press

Abstract

Feeding device (1) for a high-pressure roller press (2) for comminuting brittle grinding material (M), wherein the high-pressure roller press (2) - has at least two counter-rotating rollers (3, 4) during operation, of which at least one roller is designed as a loose roller (4) and which form a roller gap (5) between them, wherein the rollers (3, 4) are movable via bearing blocks (7, 8) displaceably mounted in a machine frame (6) of the high-pressure roller press (2), so that the at least one loose roller (4) determines the size and shape of the roller gap (5) by changing its position, where the feeding device (1) is arranged above the roller gap (5) and has two vertically movable side walls (10, 11) between which the feed material (12) is located and which are aligned approximately parallel to the center line of the roller gap (5) when the at least two rollers (3, 4) are in the rest position, wherein the vertically movable side walls (10, 11) are each accommodated in two holders (15, 16, 17, 18), wherein the two holders (15, 16, 17, 18) are each arranged on a side wall (10, 11) above the two roller ends (3', 3", 4', 4"), and wherein all brackets (15, 16, 17, 18) are height-adjustable independently of one another.

Description

[0001] The invention relates to a feeding device for a high-pressure roller press for comminuting brittle ground material, wherein the high-pressure roller press has at least two counter-rotating rollers during operation, of which at least one roller is designed as a loose roller and which form a roller gap between them, wherein the rollers are movable via bearing blocks displaceably mounted in a machine frame of the high-pressure roller press, so that the at least one loose roller determines the size and shape of the roller gap by changing its position.

[0002] For comminution of brittle material to be ground according to Schönert et al. in a high-pressure roller press, as first disclosed in German patent application DE 27 08 053 A1, it is necessary to evenly feed the nip of the high-pressure roller press with material to be ground. If too much material is fed into the nip per unit of time, the high-pressure roller press tends to vibrate and comminute ineffectively. If, on the other hand, too little material is fed into the nip per unit of time, the high-pressure comminution according to Schönert et al. collapses, and the high-pressure roller press operates like a crusher.

[0003] To achieve a uniform grinding result, the ground material fed into the roller gap of the high-pressure roller press, which is usually pre-shredded, should have as uniform a particle size distribution as possible. A uniform grinding result is also supported by evenly feeding the gap between the two grinding rollers along the length of the roller gap. For today's increasingly wider grinding rollers with a roller gap length of approximately 3 m and more, measures must therefore be taken when feeding the ground material to ensure that the quality of the ground material is uniform along the roller gap. When ground material is discharged via a conveyor belt into the feed device of a high-pressure roller press, it can happen that the discharge process itself, for example via a conveyor belt, causes segregation of the ground material.A conveyor belt with a narrower discharge width than the nip width, when used as a conveyor belt for a high-pressure roller press, can result in one part of the nip being fed with coarser material to be ground, while another part is fed with finer material to be ground. As a result of this uneven feed of material to be ground, a loose roller of the high-pressure roller press can become misaligned to avoid the uneven counterpressure of the material to be ground in the nip. The high-pressure roller press thus enters an operating state that is less efficient than with an evenly fed nip and parallel grinding rollers.

[0004] German patent application DE 42 26 182 A1 proposes compensating for roll misalignment by means of an uneven opening of the feed device to the roll gap. At the point where roll misalignment leads to an opening of the roll gap, the feed device should be less open, and vice versa. This latter patent application proposes creating a side wall of the feed device using two half-walls connected to one another by a hinge, with the hinge line running diagonally, i.e. not parallel to the roll gap. Depending on the angle of the half-walls, the feed device opening can be widened over the length of the roll gap. However, this arrangement has the disadvantage that a uniform opening of the roll gap is only possible if the two half-walls are aligned so that they lie in the same plane.

[0005] European patent EP 2 307 144 B1 teaches a feeding device for a high-pressure roller press with a chute mounted on a frame. The chute's height is adjustable. Two rotary valves are located at the lower end of the chute, which, similar to two excavator buckets, can deposit feed material to the left or right of the roller gap. The chute allows for variable feed material placement, but cannot counteract a tilted roller due to asymmetrical feed material placement.

[0006] The German utility model DE 20 2018 105 629 U1 proposes limiting the effective opening of the feed device at the ends of the roller gap by extending the side walls. This is because extending the side walls creates a cone of material with a smaller slope angle at these points, which translates into a lower feed rate per unit of time.

[0007] The object of the invention is to provide a feeding device for a high-pressure roller press with which a misalignment of the grinding rollers during operation can be counteracted.

[0008] The object of the invention is achieved in that the feed device is arranged above the roller gap and has two vertically movable side walls, between which the feed material is located, and which are aligned approximately parallel to the center line of the roller gap when the at least two rollers are in the rest position. The vertically movable side walls are each accommodated in two holders, the two holders of each side wall being arranged above the two roller ends, and all holders being height-adjustable independently of one another. Further advantageous embodiments are specified in the subclaims to claim 1.

[0009] According to the concept of the invention, it is therefore provided to equip the feeding device with two vertically movable side walls. These vertically movable side walls hold the ground material to be fed in between them. Depending on the height of the lower side wall edge above the roller gap, a correspondingly high repose cone forms on the roller gap. If the lower side wall edge of a vertically movable side wall is higher, a higher repose cone with a steeper slope angle forms. However, if the lower side wall edge of a vertically movable side wall is lower, a lower repose cone with a less steep slope angle forms, so that less ground material is deposited onto the roller gap at this point per unit of time. This uneven feeding of the roller gap is expediently achieved in such a way that more ground material is deposited at the narrower point of the roller gap when the roller is tilted, and vice versa.This uneven feeding of the roll gap over its length counteracts the opening of the roll gap by tilting, counteracting the roll tilt.

[0010] Depending on the desired maximum stroke of the brackets and thus the maximum inclination angle of the side walls, it may be advantageous to divide the movable side walls vertically into horizontally running side wall elements. When the side walls are inclined, the maximum extension of the side walls widens because the horizontal length increasingly gives way to the diagonal extension. By dividing the side wall into horizontal side wall elements, such as into horizontally running strips, the relative difference between the horizontal length and the diagonal length is reduced.

[0011] If the side walls of a vertically divided side wall are each divided into horizontally running side wall elements, then it is advantageous if the side wall elements are connected to one another via positive-locking profile grooves and profile tongues, whereby the individual, interconnected side wall elements of a side wall can be moved against one another within the positive connection. The interlocking and positive-locking profile grooves and profile tongues allow for better sealing between the side wall elements, so that in particular no finer ground material, as occurs in a circulating grinding system, can trickle out between the side wall elements and thus counteract the desired effect against the misalignment of the rollers. The lack of tightness can therefore reduce the desired effect of the side walls. This is what the profile groove and profile tongue connection is intended to prevent.The ability to move the side wall elements ensures that the effective width of the side wall does not increase too much when the side wall alignment is adjusted.

[0012] For easy handling of the loading device, the side wall supports can each be provided with a hydraulic drive or an electric drive in the form of a spindle drive, via which the supports can be adjusted independently of each other in height. For this purpose, the height adjustment can be performed automatically or by manual request, for example, by operating a switch.

[0013] To protect the drives in the very harsh environment of the high-pressure roller press, the drives can be integrated into the mounts. The mounts thus provide an external protective casing for the drives and protect them from falling rock as part of the milled material.

[0014] The side walls can be moved manually upon request, but it is also possible to integrate the side wall position into a controlled system. For this purpose, an advantageous embodiment of the feeding device is provided so that it has a control device which, as a controlled system, measures the inclination of the rollers as an angle between the two roller axes as a disturbance variable, and controls the position of the two vertically movable side walls as a manipulated variable. The control strategy is fixedly set to keep the angle between the two roller axes small. In this case, when the roller gap is opened on one side due to inclination of the loose roller on the opening side of the roller gap, the holders are moved vertically upwards by a signal from the control device, and vice versa. The control device receives a signal from an angle sensor which records the angle of the two grinding rollers.If the angle is other than 0°, the control device controls the holders arranged on the narrower side of the roller gap. At this point, the side walls rise, a larger cone of ground material forms, and the roller gap is actually widened at the narrower point by increased feed of material. The reverse control case is also possible. If the angle is other than 0°, the control device controls the holders arranged on the wider side of the roller gap. At this point, the side walls sink, a smaller cone of ground material forms, and the roller gap is tapered at the wider point by reduced feed of material.

[0015] The invention is explained in more detail with reference to the following figures. They show: Fig. 1 a simplified sketch of a high-pressure roller press with a feeding device according to the invention, Fig. 2 the feed device Fig. 1 in partially open view and the grinding rollers of the high pressure roller press from Fig. 1 in isolated representation, Fig. 3 Sketch to illustrate a roll misalignment, Fig. 4 the feed device Fig. 2 with attached side walls, Fig. 5 the feeding device Fig. 5 with inclined side walls, without enclosure and with drawn cone of ground material, Fig. 6 Feeding device with detailed illustration, Fig. 7 Feeding device with side walls divided vertically by horizontal interruptions, Fig. 8 Sketch to demonstrate the control strategy, Fig. 9 a connection of two side wall elements with a positive connection of profile groove and profile tongue,

[0016] In Fig. Figure 1 shows a simplified sketch of a high-pressure roller press 2 with a feed device 1 according to the invention. In this design, the high-pressure roller press contains two counter-rotating grinding rollers 3 and 4, of which the grinding roller 4 located in the foreground of the image is designed as a floating roller. In contrast, the grinding roller 3 located in the background of the image is designed as a fixed roller. In order to maintain a predetermined nip pressure in the high-pressure roller press 2, a design with one floating roller is necessary, with the nip pressure being controlled via a corresponding hydraulic system. A design with two fixed rollers did not allow control of the nip pressure.The grinding roller 4 arranged in the foreground of the image as a loose roller is mounted in two bearing blocks, of which one bearing block 8 arranged in the foreground of the image is shown, which itself is movably mounted in the machine frame 6 in order to be able to regulate the roller gap pressure, but also to allow non-comminuted material, such as an excavator tooth undesirably present in the ground material, to pass through the roller gap 5, in which the grinding roller 4 as a loose roller deviates. The movements of the grinding roller 4 as a loose roller can result in an undesirable roller misalignment, which is shown in . Fig. 3 is explained in more detail.

[0017] The feed device 1 with side walls 10 and 11 is arranged above the roller gap between the rotating grinding rollers 3 and 4. Between the side walls 10 and 11 is the constantly replenished grinding material, which is to pass through the roller gap between the two grinding rollers. After the grinding material M passes through the roller gap 5 between the two grinding rollers 4, flakes S of the crushed grinding material M fall out below the roller gap 5.

[0018] In Fig. 2 are the feeding device from Fig. 1 in a partially broken view and the grinding rollers 3 and 4 of the high pressure roller press from Fig. 1 in an isolated view. In this embodiment, the two side walls 10 and 11 are located in a housing. The two side walls 10 and 11 accommodate the constantly replenished grinding material between them. In the rest position of the two side walls 10 and 11, they are in a position in which the straight lower edges of the side walls 10 and 11 are aligned parallel to the roller gap 5, when the roller gap 5 is defined by two parallel grinding rollers 3 and 4 in the rest position.

[0019] In Fig. Figure 3 shows a sketch illustrating roller misalignment. The roller axes 3''' and 4''' of the two grinding rollers 3 and 4 should, if possible, always run parallel, i.e., at an angle of 0° to each other. If the idler roller 4 shifts due to uneven material feeding or other influences, an opening roller gap 5 forms, forming an angle α, which, as in the present example, can range from 0.5° to approximately 3°. Such misalignment is to be avoided by the feeding device according to the invention.

[0020] In Fig. 4 is the feeding device from Fig. 2 with inclined side walls 10, 11. At the points where the straight lower edge of the side walls 10 and 11 is further from the roller gap 5, which is arranged between the two rollers 3 and 4, a higher cone of ground material M is formed, as shown in Fig. 5 is shown.

[0021] In Fig. 5 is the feeding device from Fig. 5 with inclined side walls, 10 and 11 without enclosure and with a cone of grinding material M drawn in, with the grinding material M stored as feed material 12 between the side walls 10 and 11. The cone of grinding material extends into the roller gap 5 between the two grinding rollers 3 and 4 and is delimited by the side walls 10 and 11. The side walls 10 and 11 extend to the roller ends 3' and 4'.

[0022] In Fig. Figure 6 shows a detailed view of a feeding device according to the invention, although the housing is not shown. The two side walls 10 and 11 are suspended in the end brackets 15, 16, 17, and 18. The brackets 15, 16, 17, and 18 have integrated drive devices 50, 51, 60, and 61, via which the respective end of the corresponding side wall 10 and 11 can be raised or lowered.

[0023] In Fig. Figure 7 shows a feeder with side walls divided vertically by horizontal interruptions; here, too, the enclosure is omitted. The side walls are vertically divided into three horizontal side wall elements. The front side wall is divided into side wall elements 20, 21, and 22, while the rear side wall is divided into three side wall elements 30, 31, and 32, with side wall elements 31 and 32 concealed here. This division allows the ends of the side walls to be raised higher without the effective width of the side walls becoming too wide due to the diagonal extension.

[0024] In Fig. Figure 8 shows a diagram illustrating a control loop. The upper diagram shows the two grinding rollers 3 and 4, with the grinding rollers 3 and 4 having a pattern of hard particles on their surfaces. A bed of grinding material M lies on the roller gap 5, with the bed being larger on the right-hand side, namely exactly where the roller gap 5 has the smallest width due to the inclination of the grinding roller 4. This uneven deposition of grinding material M is prevented by the side walls 3 and 3 being raised on one side (cf. Fig. 5). The uneven feeding of grinding material M along the roller gap 5 causes the roller gap 5 on the left side in the illustration to become smaller due to a pressure device, whereas the roller gap 5 on the right side of the roller gap 5 in this illustration becomes larger. The aim is to position the grinding roller 4 in such a way that the roller gap 5 is again parallel to the two grinding rollers 3 and 4, i.e. with an opening as close as possible to 0°, so that the edges of the roller gap 5 form an angle of α = 0°.

[0025] To avoid the tilted grinding roller 4 in the upper picture of Fig. 8 straight again, the control device 70 receives a signal from an angle sensor (not shown here) about the angle α, which is different from zero. The control device 70 then sends a signal to the drive devices 50, 51 and 60, 61 and thereby adjusts the side walls 10 and 11 so that the cone of material to be ground M is positioned as shown in the upper illustration. This cone of material to be ground then causes the grinding roller 4, as a loose roller, to align itself straight. If the grinding roller 4 is aligned straight, the corresponding signal of the angle α is sent to the control device 70, which then adjusts the side walls 10 and 11 again so that the cone of material to be ground M is positioned as shown in the lower illustration. Fig. 8, in which the deposition of grinding material M on the roller gap 5 is evenly distributed over the length.

[0026] In Fig.Finally, Figure 9 shows a connection between two side wall elements 20, 21 with a positive connection consisting of a profile groove 40 and a profile tongue 41, showing a vertical section through the side walls. The type of profile connection allows the side wall elements 20, 21 to be displaced horizontally relative to one another in the direction of the profile groove. LIST OF REFERENCE SYMBOLS 1 feeding device 2 high-pressure roller presses 3 rollers 3' roller end 3'' roller end 3''' roller axis 4 Loose roller 4' roller end 4'' roller end 4''' roller axis 5 roller gap 6 machine frames 7 bearing block 8 bearing block 10 Side wall 11 Side wall 12 Feed material 15 Bracket 16 Bracket 17 Bracket 18 Bracket 20 side wall element 21 Side wall element 22 side wall element 30 side wall element 31 side wall element 32 side wall element 40 profile groove 41 profile spring 50 drive device 51 Drive device 60 drive device 61 Drive device 70 Control device M ground material S Schülpen

Claims

[1] Feeding device (1) for a high-pressure roller press (2) for comminuting brittle grinding material (M), wherein the high-pressure roller press (2) - has at least two counter-rotating rollers (3, 4) during operation, of which at least one roller is designed as a loose roller (4) and which form a roller gap (5) between them, wherein the rollers (3, 4) are movable via bearing blocks (7, 8) displaceably mounted in a machine frame (6) of the high-pressure roller press (2), so that the at least one loose roller (4) determines the size and shape of the roller gap (5) by changing its position, where the feeding device (1) is arranged above the roller gap (5) and has two vertically movable side walls (10, 11) between which the feed material (12) is located and which are aligned approximately parallel to the center line of the roller gap (5) when the at least two rollers (3, 4) are in the rest position, wherein the vertically movable side walls (10, 11) are each accommodated in two holders (15, 16, 17, 18), wherein the two holders (15, 16, 17, 18) are each arranged on a side wall (10, 11) above the two roller ends (3', 3", 4', 4"), and wherein all brackets (15, 16, 17, 18) are height-adjustable independently of one another. [2] Feeding device according to claim 1, characterized by that the movable side walls (10, 11) are divided vertically into horizontally extending side wall elements (20, 21, 22, 30, 31, 32). [3] Feeding device according to claim 2, characterized bythat the side wall elements (20, 21, 22, 30, 31, 32) of each vertically divided side wall (10, 11) are connected to one another via positive-locking profile grooves (40) and profile springs (41), wherein the individual, interconnected side wall elements (20, 21, 22, 30, 31, 32) of each side wall (10, 11) are displaceable relative to one another within the positive-locking connection. [4] Feeding device according to one of claims 1 to 3, characterized by that the holders (15, 16, 17, 18) each have a hydraulic drive (50, 51, 60, 61) or an electric drive in the form of a spindle drive, via which the holders (15, 16, 17, 18) can be adjusted in height independently of one another. [5] Feeding device according to claim 4, characterized by that the drives (50, 51,60, 61) are integrated in the brackets (15, 16, 17, 18). [6] Feeding device according to one of claims 1 to 5, characterized by , that this has a control device (70) which as a controlled system, the inclination of the rolls is measured as an angle (α) between the two roll axes (3''', 4''') as a disturbance variable, and as a control variable, controls the position of the two vertically movable side walls (10, 11), whereby as a control strategy is fixed to keep the angle (α) between the two roller axes (3''', 4''') small, in that when the roller gap (5) is opened on one side by tilting the loose roller (4) on the opening side of the roller gap (5), the holders (15, 16, 17, 18) are moved vertically upwards by a signal from the control device (70) and vice versa. [7] Feeding device according to claim 6, characterized by that the height of the individual brackets (15, 16, 17, 18) can be manually adjusted via a request signal.

Images