EP0127215A1 - Annular machine for contacting solid substances with gases - Google Patents

Abstract

1. An annular machine for contacting solids and gases, wherein the gases are passed through a solids bed and a temperature difference exists between the gases and solids, comprising gas-permeable grates, which are supported by a carrying structure revolving on wheels and which are adapted to be lowered about a horizontal hinge at the discharge station, and inside and outside walls secured to the carrying structure, characterized in that the carrying structure consists of radially extending spokes (1), which are interconnected only on the inside by a ring structure (2), which is guided on the inside by horizontal rollers (3) on a circular track (4), the carrying structure is supported on circular rails (6, 6a) on the inside by wheels (5) mounted on the spokes (1) or on the ring structure (2), and on the outside by wheels (5a) mounted on the spokes (1), each of the gas-permeable grates (7) is mounted so that it is adapted to be lowered about a horizontal hinge (8), between two adjacent spokes (1), the free space (9) between adjacent grates (7) is covered by a cover (10), stakes (11) are mounted on the outside on the spokes (1) and on the inside on the spokes (1) or the ring structure (2), and the side walls (12, 12a) are secured to the stakes (11, 11a).

Description

The invention relates to a ring-shaped machine for contacting solids and gases, the gases being passed through a bed of solids and a temperature difference between gases and solids consisting of gas-permeable grids which are supported by a supporting structure rotating on wheels and which at the unloading point a tilt axis are arranged lowerable, unu attached to the support structure inner and outer wall.

In many cases, solids are thermally treated with the passage of gases, either being heated or cooled. A thermal treatment with heating takes place e.g. when sintering ores, burning pellets, calcining, coking coal, smoldering oil shale etc. A thermal treatment with cooling takes place e.g. when cooling hot sinter, coke etc. When removing pollutants from gases at an elevated temperature, the solid bed consists of materials with adsorbent properties. In most cases, the material must also be cooled down again after heating. When heated, gases are passed through the material or oxygen-containing gases are passed through to burn fuel present in the material. Cooling gases are passed through during cooling.

It is known to carry out this thermal treatment of solids on rotating ring-shaped machines in which an annular, endless grate band is formed from segment-shaped, gas-permeable gratings. At the loading point, the material is continuously fed in at a certain layer height and removed after one turn at the unloading point.

Round machines are known in which the segment-shaped grids are supported by a supporting structure which consists of two ring carriers arranged concentrically to one another, which are connected to one another by spokes and which rotate with rollers on circular rails. The segment-shaped grids are attached to the ring supports at one end with a pivot axis. The other end of the grids is supported by rollers on rails which have a lowering at the unloading point, so that the grates are tilted and emptied (DE-PS 10 68 496). This is perfect for the grates while eire stable _T ragkonstuktion, but it is subject to strong temperature effects and considerable thermal expansions and tensions. The thermal expansions have a negative impact on the concentricity of the machine and the stresses can lead to breaks.

It has also already been proposed to design the segment-shaped grids as grate carriages and to fasten each grate carriage to an outer ring-shaped support by means of two bearings attached to its outer cheek. A running rail is attached to the underside of the ring-shaped carrier, which supports the carrier on stationary rollers. Ostwagen on the inner cheek cer _R is an impeller secured respectively, which is plotted on a circular rail. This rail is lowered at the unloading point so that the grate wagons are tilted towards the center point of the machine (DE-OS 16 08 018; DE-CS 18 07 680). Since the bearings are subject to heavy wear, relatively quick wear is not an option avoid. This causes skewing forces on the rollers of the grate wagons, which put additional strain on the horizontal guidance of the machine and also accelerate wear. Sealing without any remaining gaps is not possible.

Furthermore, it was proposed to support the segment-shaped grate carriages in their radial central axis by means of a bearing on an internal ring-shaped carrier, the carrier being supported on a circular rail by means of rollers. A roller is mounted ostwagen on the outer side of the _R in the center axis, which is supported on a circular rail. The grate wagons are tipped around their radial center axis in the unloading station. On the outside, a second roller is attached offset to the central axis, which runs under a circular rail outside the unloading station during rotation and thus prevents tipping and which is performed in the unloading station in a setting that causes the tipping. The required expansion point between the outer and inner cheeks of the grate wagon is sealed by spring seals or labyrinth seals ( _D E-OS 30 46 605). The above disadvantages also apply here. Since the axis of rotation is supported in three positions, even with slight deviations in the height of the rail and the diameter of the rollers from the ideal, theoretical values, very heavy loads on the bearings and the axis of rotation occur. Sealing without any remaining gaps is not possible.

The invention has for its object to avoid the disadvantages of the known ring-shaped machines and in particular to avoid the stresses caused by temperature differences in the supporting structure, to achieve a perfect concentricity despite the thermal expansion and to allow a good seal of the machine.

According to the invention, this object is achieved by aassing the supporting structure from radially arranged spokes exists, which are connected to one another only by an annular structure, the annular structure is guided on the inside by horizontal rollers on a circular path, the supporting structure on the inside by wheels attached to the spokes or the annular structure and on the outside by wheels attached to the spokes on circular rails is supported and the gas-permeable grids are each arranged between two adjacent spokes that can be lowered about a tilting axis, the free space between adjacent grilles is covered by a cover, stanchions are arranged on the outside of the spokes and on the inside of the spokes or the annular construction, and on the stanchions aie side walls are attached.

The ring-shaped structure can consist of a circular ring or a polygonal steel structure. The ring-shaped construction can be rigid or can be equipped with joints in the vertical and / or horizontal direction in order to even out the transmission of the loads. The spokes can be made from round material, section steel or hollow sections. The spokes are clamped in the ring-shaped construction. The wheels are preferably designed without wheel flanges so that the horizontal rollers do not adversely affect the centering. The horizontal rollers are attached to the annular structure and run on a circular path, generally on a rail. It is also possible to use the side surfaces of the rails for the wheels as a horizontal guide for the rollers. The gas-permeable grids can be trapezoidal or rectangular. Eastern the free space between adjacent _R is covered by appropriately shaped covers. The covers are expediently arranged to be radially displaceable and provided with perforations. The grids are expediently removed from the spokes by means of laterally attached pins in corresponding receiving devices. The verb The extension line of the pins is the tilting axis of the gratings. The term "stanchions" is understood to mean vertical supports which absorb the side pressure of the material bed. The side walls can be circular or polygonal. The direction of flow of the gases can be specified from bottom to top as well as from top to bottom. For this purpose, stationary annular gas channels or several individual wind boxes can be arranged both below and above the grate. These gas supply and discharge devices are sealed against the rotating machine by means of seals. The discharge station can be sealed against undesired gas entry or gas exit by means of a discharge lock for the material. The machine can be driven in a known manner by non-positive or positive drives with stationary or rotating motors. The terms "inside" and "outside" should always be understood from the center of the grate. By dividing the annular gas channels below and / or above the grids or by designing them in the form of wind boxes, it is possible to pass the gas through one or more times in succession through different treatment zones, to direct different gas streams through different treatment zones or to supply a gas stream to all treatment zones conduct and derive separate gas flows from the different treatment zones. This allows for example an enhancement of volatiles achieved in the gas, a high degree of purification of the gas stream can be effected, the _D can be increased urchschnittstemperatur of the gas, a partial gas flow are achieved at a very high temperature, or various treatments are sequentially performed on the machine. This enables good energy recovery.

A preferred embodiment is that the tilting axis of the grids is arranged tangentially between adjacent spokes. This means that no forces are required to break or lift the material bed. With fried or sintered material bed, it is expedient to arrange the tilt axis on the inside in order to avoid constraints of the slipping material bed.

A preferred feature Lesteht the fact that the grids in the horizontal position at its the tilt axis opposite free side ragkonstruk- means of a latch on aer _T tion be locked, the lock is opened in the discharge station, the free side of the grates lowered on a rail track and again is brought up and the lock is closed again before the task station. It is fundamentally possible to support the free end of the grids in a horizontal position outside the unloading station by a roller arranged under this end and running on a rail. However, due to unavoidable height differences and wear on the rails and rollers, there are constant vertical movements of the gratings and thus of the material bed. This is avoided by the lock.

The lock preferably consists of a double-supported rod with ends protruding on both sides. The grate plate is supported on the cantilever arm arranged within the side walls. A roller is arranged on the cantilever arm arranged outside the side walls. At the unloading point, the bolt is moved radially using a positive guidance. Before the bolt is moved, the grate plate is raised to relieve the bolt. This measure protects the grate plate from wear and the forces required to move the bolt are kept small.

The lowering and raising of the gratings on the railroad in the area of the unloading station can be done by means of rollers or runners attached to the gratings.

A preferred embodiment is that compensator-like beads are arranged at least in the outer wall. The Beads can be arranged between all spokes or at certain intervals. Their number depends on the existing thermal expansion of the spokes and the walls. In the case of small dimensions, beads in the inner wall may not be necessary. In the event of greater thermal expansion, beads are arranged in the outer and inner walls between all spokes. These beads do not exert any or only slight tangential forces on the spokes.

A preferred feature is that the _A b-cover from sharp roof-shaped plates is arranged displaceable in the radial direction between the stanchions and provided with perforations. The tip of the plates is conveniently in the middle above the spokes. However, it can also lie outside the center. The radial displaceability of the plates can be achieved by resting on the stanchions on which the plates rest loosely. To prevent material from falling through the perforations, these can be equipped with coverings. The perforations can have any shape, such as slit-shaped, round, etc. These designs ensure that the material easily falls off the covers, no radial forces are exerted on the stanchions and spokes by the covers, the gases also flow through the material over the covers and a flow of cooling gas cools the spokes.

A preferred embodiment is that vertical partitions are arranged between the spokes and the covers, which are arranged radially displaceably with at least one longitudinal edge, preferably with the longitudinal edge on the spoke. This prevents gases from escaping through the spokes in the locks of the unloading and loading station. The movability of the partition walls prevents the transfer of radial forces to the spokes.

A preferred embodiment is that the sides Immerse the walls below the spokes in stationary, ring-shaped water cups. The side walls can dip into the water cups with their lower ends or extensions attached to them. The surface of the water cups can be covered except for one slit. The water cups are gas-tight connected to the wind boxes or gas channels under the grates. This ensures an absolute and wear-free seal.

A preferred embodiment consists in that the side walls are immersed in stationary water cups above the spokes, a stationary gas hood is arranged above the side walls and has stationary seals outside the water cups. This achieves an absolute and wear-free seal with the gas hood over the grate.

A preferred embodiment is that water cups are attached to the stanchions, the side walls above the spokes are immersed in the water cups, a stationary gas hood is arranged above the side walls, and the gas hood with seals is also immersed in the water cups. In addition to an absolute and wear-free seal, this eliminates the need for an additional stationary seal on the gas hood and there are no secondary gas spaces.

A preferred embodiment is that the spokes are hollow and are equipped with cooling. Cooling can be done by blowing in air, with fans rotating with the machine.

A preferred embodiment consists of feeding cab water from one of the water cups attached to the stanchions into the spokes and from there into the other water cup. This allows a very effective cooling of the spokes in a simple manner.

A preferred embodiment is that the wheels are designed as steering wheels. The term "steering wheels" is to be understood as meaning wheels which have a vertical pivot axis. This pivot axis is arranged at a distance from the axis of rotation of the wheels. Through this distance, the wheels adjust tangentially, approx this wheel suspension fulfills the well-known mathematical equation of the drag curve. With this device, the required tangential position of the wheels is achieved without difficult alignment work.

One embodiment is that the ring-shaped construction is equipped with horizontal joints and / or vertical joints at intervals. This configuration is used in particular in the case of very large machines, since it balances the loads acting on the rollers and wheels in the horizontal and / or vertical direction.

• Fig. 1 ist eine schematische Draufsicht auf eine runde Maschine, wobei im unteren Teil die Tragkonstruktion mit den Rosten dargestellt ist, im rechten Teil das Prinzip der über Rollen geführten, innen liegenden, steifen ringförmigen Konstruktion mit darin befestigten Speichen gezeigt ist und im oberen Teil die Roste in Endladeposition dargestellt sind.
• Fig. 2 ist ein senkrechter Querschnitt durch die Maschine zwischen zwei Speichen gemäß I-I in Figur 1 bzw. gemäß I-I in Figur 3. Die geschnittenen Teile sind durch dickere Strichstärke cagestrellt. Die gestrichelte Darstellung des gasdurchlässigen Rostes zeigt diesen in der Endladestellung.
• Fig. 3 ist ein horizontaler Schnitt gemäß II-II in Figur 2.
• _Fig. 4 ist ein Schnitt gemäß III-III in Figur 3 und zeigt die rerforierte Abdeckung des freien Raumes zwischen zwei benachbarten Speichen, die in der Figur 3 auf halber Ringbreite dargestellt ist.
• Fig. 5 zeigt eine geänderte Ausbildung der Abdichtung gegenüber der Figur 2.
• Fig. 6 zeigt eine Ausbildung der Räder als Lenkräder.
• Fig. 7 zeigt schematisch eine Abwicklung der Aufgabe- und Entladestation.
• Fig. 8 ist ein horizontaler Schnitt gemäß II-II in Figur 2, wobei die ringförmige Konstruktion mit Gelenken ausgestattet ist.

The invention is explained in more detail with reference to figures.

• Fig. 1 is a schematic plan view of a round machine, in the lower part of the supporting structure with the grates is shown, in the right part the principle of the internal, rigid ring-shaped construction with spokes mounted therein is shown and in the upper part the gratings are shown in the unloading position.
• Fig. 2 is a vertical cross section through the machine between two spokes according to II in Figure 1 and according to II in Figure 3. The cut parts are cagestrellet by thicker stroke. The broken line of the gas-permeable grate shows this in the unloading position.
• 3 is a horizontal section according to II-II in FIG. 2.
• _F ig. 4 is a section according to III-III in FIG. 3 and shows the perforated covering of the free space between two adjacent spokes, which is shown in FIG. 3 over half the ring width.
• FIG. 5 shows a modified design of the seal compared to FIG. 2.
• Fig. 6 shows an embodiment of the wheels as steering wheels.
• Fig. 7 shows schematically a handling of the loading and unloading station.
• Fig. 8 is a horizontal section according to II-II in Figure 2, wherein the annular structure is equipped with joints.

The support structure of the ring-shaped machine consists of the radially arranged spokes 1, which are clamped inside the ring-shaped structure 2 and extend over the ring width without further connection. The support structure is rotatably supported on the inside by the wheels 5 on the circular rail 6 and on the outside by the wheels 5a on the rail 6a. The support structure is guided centrally by the horizontal rollers 3 on a horizontally arranged circular rail 4. A gas-permeable grate 7 is arranged between adjacent spokes 1 about a tilt axis 8 arranged tangentially on the outside. The free space 9 between two adjacent grids 7 above the spokes 1 is covered by roof-shaped covers 10n. The inner stanchions 11 are fixed on the annular structure 2 and the outer stanchions 11a on the spokes 1. The inner side wall 12 is attached to the stanchions 11 and the outer side wall 12a to the stanchions 11 a. The horizontal position of the grids 7 outside the unloading station 14 is effected by the lock 13, which on the ring-shaped construction tion 2 is attached. Shortly before the unloading station 14, the lock 13 is relieved by the auxiliary roller 26 running onto the rail 15 and opened by a stationary guide 27. In the unloading station 14, the auxiliary roller 26 runs on the lowered rail 15, the grate 7 is inclined so far that the slip angle of the treated material is surely exceeded. Then the grate 7 is raised again to the horizontal position and the lock 13 is closed by the opposing part of the positive guide 27 before the grids 7 reach the loading station 16. Between the stanchions 11 and 11a, compensator-like beads 17 are arranged in the side walls 12 and 12a, which enable thermal diameter changes without affecting the spokes 1.

Brackets 28 are fastened to the side walls 12, 12a, on which the roof-shaped covers 10 lie freely displaceable in the radial direction. The covers 10 are provided with slots 18 for the passage of the gaseous medium. A vertical dividing wall 19 is attached to the ridge line of the roof-shaped cover 10, and its lower edge is arranged so that it can move in a seal 29 on the spoke.

The extension of the lower edge of the side wall 12 dips into the stationary water cup 20 and the lower edge of the side wall 12a into the stationary water cup 20a. As a result, the underside of the machine and the gas channel 30 are completely sealed against the outside atmosphere. In FIG. 2, the bent upper edge of the side wall 12 is immersed in the stationary water cup 21 and the upper edge of the side wall 12a in the stationary water cup 21a. The stationary gas hood 22 is sealed against the outside atmosphere by means of the side covers 31, 31a and the stationary sanitary cups 23, 23a. In Figure 5, the gratings and the locking are not shown compared to Figure 2. The water cups 24, 24a, which rotate, are fastened to the stanchions 11, 11a. The top edges of the side walls 12, 12a and the extensions 25, 25a of the gas hood 22 dip into the water cups 24, 24a. The spoke 1 is hollow. The water cup 24 is connected to the water cup 24a via line 32, spoke 1 and line 32a. By adding water to the water cup 24 and withdrawing water from the water cup 24a, water is passed through the spoke 1 and the latter is cooled in the process.

In Figure 6, the wheels 5, 5a are designed as steering wheels. The wheels 5, 5a are fixed with their axes of rotation 33 in the housing 34. The housing 34 is fastened to the steering bearing 35 and can be pivoted about its central axis. The center axes of the steering bearings 35 and the axes of rotation 33 are arranged at a distance from one another, as a result of which the steering effect is achieved.

The arrow in FIG. 7 indicates the direction of movement of the machine. In front of and behind the unloading station 14, the gas channel 30 merges into a cover plate 36. Cross webs 37 are attached to the spokes 1 below and produce a seal with the cover plates 36.

In FIG. 8, the annular construction 2 between the spokes 1 is equipped with horizontally acting joints 38 and vertically acting joints 39. The loads acting on the horizontal rollers 3 are equalized by the joint 38 and the loads acting on the wheels 5 by the joint 39.

The advantages of the invention are that no stresses caused by temperature differences occur in the supporting structure, since the parts of the supporting structure can expand from one another without hindrance. Despite this expansion, perfect concentricity is achieved because the internal guide parts are not thermally stressed and because the spokes can expand in the radial direction without hindrance. A perfect seal is possible.

Claims (13)

1. Ring-shaped machine for contacting solids and gases, the gases being passed through a bed of solids and a temperature difference between gases and solids consisting of gas-permeable grids, which are supported by a supporting structure rotating on wheels and which at the unloading point about a tilting axis are arranged lowerable, and the inner and outer walls fastened to the supporting structure, characterized in that the supporting structure consists of radially arranged spokes (1) which are connected to one another only by an annular structure (2), the annular structure (2) on the inside is guided by horizontal rollers (3) on a circular path (4), the supporting structure on the inside by wheels (5) attached to the spokes (1) or the ring-shaped structure (2) and on the outside by wheels (5a ) is supported on circular rails (6, 6a) and the gas-permeable grids (7) each between two adjacent spokes (1) are arranged to be lowerable about a tilt axis (8), the free space (9) between adjacent grids (7) is covered by a cover (10), on the outside on the spokes (1) and on the inside on the spokes (1 ) or the annular structure (2) stanchions (11) are arranged and the side walls (12, 12a) are fastened to the stanchions (11, 11a). 2. Annular machine according to claim 1, characterized in that the tilt axis (8) of the grids (7) between adjacent spokes (1) is arranged tangentia-. 3. Ring-shaped machine according to claim l or 2, characterized in that the gratings (7) in a horizontal position on their the tilting axis (8) opposite free side by means of a lock (13) on the supporting structure be locked, the lock (13) in the unloading station (14) is opened, the free side of the grids (7) is lowered on a rail track (15) and brought up again and the lock (13) is closed again in front of the loading station (16) becomes. 4. Annular machine according to one of claims 1 to 3, characterized in that at least in the outer wall (12a) compensator-like beads (17) are arranged. 5. Annular machine according to one of claims 1 to 4, characterized in that the cover (10) consists of pointed roof-shaped plates which are arranged in the radial direction between the stanchions (11) and are provided with perforations (18). 6. Annular machine according to one of claims 1 to 5, characterized in that between the spokes (1) and. the covers (10) are arranged vertical dividing walls (19) which are arranged to be radially displaceable at least with one longitudinal edge, preferably with the longitudinal edge on the spoke (1). 7. Annular machine according to one of claims 1 to 6, characterized in that the side walls (12, 12a) below the spokes (1) dip into stationary water cups (20, 20a). 8. Ring-shaped machine according to one of claims 1 to 7, characterized in that the side walls (12, 12a) above the spokes (1) dip into stationary water cups (21, 21a), a stationary gas hood (22) over the side walls (12 , 12a) which has stationary seals (23, 23a) outside the water pockets (21, 21a). 9. Ring-shaped machine according to one of claims 1 to 8, characterized in that on the stanchions (11, lla) water cups (24, 24a) are attached, the side walls (12, 12a) above the spokes (1) in the water cups ( 24, 24a), a stationary gas hood (22) is arranged above the side walls (12, 12a), and the gas hood (22) with seals (25) is also immersed in the water cups (24, 24a). 10. Annular machine according to one of claims l to 9, characterized in that the spokes (1) are hollow and are equipped with a cooling. 11. A ring-shaped machine according to claim 9 and 10, characterized in that water from one of the water cups (24, 24a) attached to the stanchions (11, lla) into the spokes (1) and from there into the other water cup (24, 24a ) is conducted. 12. Annular machine according to one of claims ₁ to 11, characterized in that the wheels (5, 5a) are designed as steering wheels. 13. Annular machine according to one of claims 1 to 12, characterized in that the annular structure (2) is equipped at intervals with horizontal joints (38) and / or vertical joints (39).

Images