EP0081551B1 - Coating for a hearth having an at least approximately circular cross-section - Google Patents

Abstract

The coating is subdivided radially into at least two layers (11, 12, 13) and axially into at least two portions. A gas-tight sheet (14) is arranged between the portions of the coating and comprises radially at least three sections (16, 17, 18) which are interconnected so that the internal section can be withdrawn along an axial direction.

Description

The invention relates to a lining for a combustion chamber which is at least approximately round in cross section and which is divided into at least two layers in the radial direction and at least two sections in the axial direction, with a gas seal made of metallic foil material which extends in the axial direction between two layers Sealing part and a sealing part bent at right angles from this in the boundary region between two layers and extending in the radial direction between two sections.

In the case of a lining of this type known from DE-A No. 2948385, the gas seal is intended to prevent heat flow in the radial direction from the inside to the outside and should take into account the shrinking of the lining which is typical of fiber material. A gas seal that extends continuously from the inside to the outside over at least two layers is not provided, since in the region of the joints between two adjacent layers the essentially horizontally running sealing sections collide with one another at best. A tight connection cannot be achieved in this way. The same also applies to the bent areas which engage in a joint between two adjacent layers, since a bent area of a possibly existing adjacent section is not provided in the same joint. Since a continuous seal is not present in the known lining and the lining consists of fiber material, there is also no mention of difficulties which arise due to the fact that different thermal expansions occur in the individual layers, as is unavoidable in the case of a multilayer lining made of solid material is.

Accordingly, the object of the invention is to design a lining of the type described in the introduction in such a way that it adapts well to different thermal expansions in the individual layers and also enables or simplifies repairs in partial areas of the lining.

To achieve this object, the invention proposes that the sealing parts, which extend in the radial and axial direction, are connected to a gas seal, which is known per se and extends continuously from the inside to the outside of the lining, in such a way that adjacent sealing parts which extend in the radial direction are in the region between overlap two layers of the lining and are releasably connected in the manner of a plug connection in the axial direction.

This configuration takes into account in a very particularly advantageous manner not only the possible removal of an inner sealing part and the connection of a new sealing part to the sealing part of the next outer layer. Rather, this configuration also ensures that the adjacent layers are able to absorb different thermal expansions, without the seal being adversely affected, in particular being damaged. This is achieved in that the overlapping, axially extending sealing parts can slide against one another without the sealing effect being impaired.

The overlapping, axially extending sealing parts can be arranged laterally next to each other and adjacent to each other between two layers. However, an embodiment is also possible in which at least one of the overlapping, axially extending sealing parts is bent back and the other cooperating sealing part can be inserted into the fold formed in this way. In this case, the two sealing parts are pushed into one another in the manner of a plug connection, as a result of which the sealing effect is further improved.

According to a further proposal of the invention, the sealing parts extending in the radial direction can be arranged in the axial direction at different heights and the overlapping sealing parts extending in the axial direction bridge the height difference between two adjacent sealing parts extending in the radial direction. Such a step-like arrangement of the sealing parts extending in the radial direction favors the sealing effect in the radial direction since there is no continuous joint from the inside to the outside.

In the case of the aforementioned configuration of the one sealing part extending in the axial direction as a fold, the arrangement is expediently such that the fold is open at the bottom. In the aforementioned step-like arrangement of the sealing part extending in the radial direction, the fold can be attached to that of two adjacent such sealing parts which is arranged higher in the axial direction than the other sealing part which can be inserted into the fold.

In order to achieve a further improvement in the sealing effect, the free edge of the sealing part which can be inserted into the fold can be folded back by 180 ° to form a sealing lip. An additional improvement of the sealing effect is also the possibility of folding over the free edge of the section forming the fold of the sealing part extending in the axial direction towards the outside of the fold. The folded areas also increase the strength of the free edge.

A particular increase in both the strength of the edges and the sealing effect is achieved if a sealing part is composed of a ring segment extending in the radial direction and a strip extending in the axial direction, which acts as a connecting part, which are connected to one another by folding .

According to a further feature of the invention, the outer most sealing part can be arranged with its outer edge between a support ring and a retaining ring, the two rings being screwed together and connected to one another in another way. The layers of the lining of at least one section can also be supported on an annular support bracket, the outer edge of the outer sealing part being held in a clamping manner between the lining and the support bracket.

The gas seal is also advantageously divided into a plurality of sealing parts in the circumferential direction, the end regions of which face one another in the circumferential direction overlap one another. This enables good adaptability of the seal to the thermal expansion occurring in the circumferential direction. Appropriately, one of the two end regions of a sealing part lies above and one below the end region of an adjacent sealing part, with at least one of the sealing parts overlapping the adjacent sealing parts with both end regions. This makes it easy to mount the seal over the circumference of the lining.

• Fig. 1 einen schematischen Längsschnitt durch einen Feuerungsraum mit einer dreischichtigen Auskleidung;
• Fig. 2 als Schnitt einen Teilbereich der Auskleidung mit einer ersten Ausführungsform der Gasdichtung;
• Fig. 3 in Draufsicht die Gasdichtung im Bereich einer Auskleidungsschicht, gesehen in axialer Richtung;
• Fig. 4 die Gasdichtung nach Fig. 3, gesehen in radialer Richtung;
• Fig. 5 als Teilschnitt durch die Auskleidung eine nächste Ausführungsform der Gasdichtung;
• Fig. 6 in einer abgewandelten Ausführungsform den Verbindungsbereich zwischen zwei Teilen der Gasdichtung;
• Fig. 7 eine nächste Ausführungsform der Gasdichtung im Verbindungsbereich;
• Fig. 8 eine weitere abgewandelte Ausführungsform der Gasdichtung im Nachbarbereich zwischen zwei Schichten der Auskleidung, und
• Fig. 9 eine Anordnung der Gasdichtung im äusseren Randbereich der Auskleidung.

Some preferred embodiments of the invention are described in more detail below with reference to a drawing. In detail show:

• Figure 1 is a schematic longitudinal section through a furnace with a three-layer lining.
• 2 shows a section of a portion of the lining with a first embodiment of the gas seal;
• 3 shows a top view of the gas seal in the region of a lining layer, seen in the axial direction;
• 4 shows the gas seal according to FIG. 3, seen in the radial direction;
• 5 shows a partial embodiment through the lining of a next embodiment of the gas seal;
• 6 in a modified embodiment the connection area between two parts of the gas seal;
• 7 shows a next embodiment of the gas seal in the connection area;
• 8 shows a further modified embodiment of the gas seal in the adjacent area between two layers of the lining, and
• 9 shows an arrangement of the gas seal in the outer edge region of the lining.

First, the general structure of a furnace, which here has the form of a pressure reactor and is used to gasify carbon-containing material, will be described with reference to FIG. 1. Average temperatures up to 1100 ° C occur here, which can reach peak values of up to 1500 ° C. The operating pressure will generally be between 10 and 30 bar, although maximum values up to over 100 bar are possible. Furthermore, such a pressure reactor can have an outside diameter of up to 4 m and a length of up to 10 m or more.

The pressure reactor has an outer steel jacket 10 and a lining which is made of refractory building materials and forms three layers 11, 12 and 13. Each of these layers 11, 12 and 13 is along the length of the pressure reactor, i.e. in the axial direction, divided into two sections, one above and the other below a gas seal generally designated by reference numeral 14. Since the gas seal 14 has the task of preventing the penetration of gas into the outer part of the lining due to pressure differences that can occur between the lower and the upper part of the interior 15 during a reaction process, further gas seals 14 are also used as required be arranged in the higher area of the pressure reactor if such pressure differences are also to be expected there.

2 to 9 to be explained below show, on a much larger scale, different embodiments of the gas seal 14 on their own or in connection with the corresponding installation area between the layers 11, 12 and 13 of the lining.

In the embodiment according to FIG. 2, the gas seal is formed in the radial direction by three sealing parts 16, 17 and 18, of which the sealing part 16 between the two sections of the layer 11 adjoining one another in the axial direction and the part 17 between the two adjoining one another in the axial direction Portions of the layer 12 and the Teit 18 between the two axially adjacent portions of the layer 13 of the lining is arranged. The sealing part 16 can, as shown for example below in connection with FIGS. 3 and 4, be divided over the circumference into individual sector-shaped parts which overlap accordingly. Since the lining cross section is circular, the strip 16a of the sealing part 16 runs in a correspondingly circular arc, which also applies to the other strips of the sealing parts which extend in the axial direction and which are described in connection with the later exemplary embodiments.

The sealing part 16, like the sealing parts 17 and 18 and the sealing parts to be described in connection with the other exemplary embodiments, consists of a metal foil, the thickness of which is between 0.01 and 1 mm. In general, thicknesses between 0.05 and 0.3 mm will be used, although different foils can of course also be selected within a gas seal. As a material for the film, it is advisable to use high-temperature steels with relatively high alloy proportions or another high-temperature alloy.

The sealing part 17 which adjoins the sealing part 16 towards the outside has on it Both ends have a strip 17a bent over in the axial direction, one of which is bent downwards and overlaps with the strip 16a of the sealing part 16. The upwardly bent strip 17a on the outer side of the sealing part 17 overlaps with a downwardly bent strip 18a of the sealing part 18 is. An annular seal 20 is inserted between the sealing part 18 and the support ring 19. On the top of the sealing part 18 is a retaining ring 21 which is screwed to the support ring 19.

The overlap between the sealing parts 16, 17 and 18 is designed such that the sealing parts can be separated from one another by pulling them off in the axial direction. If, for example, you only want to replace the lower section of the inner layer 11 of the lining, the sealing part 16 can be removed after the upper section has been temporarily intercepted and the lower section of the layer 11 has been removed and, if necessary, replaced by a new sealing side 16. The overlapping strips 16a and 17a or 17a and 18a also allow compensation for different thermal expansions in the axial direction. The film, from which the sealing parts 16, 17 and 18 are made, is shown both in Fig. 2 and in the following figures in relation to the thickness of the layers 11, 12 and 13 on a disproportionately large scale in order to better show the overlap can. In practice, these overlap areas lie in a relatively narrow gap between two adjacent layers 11, 12 or 13 of the lining or between sections of the respective lining layers lying one above the other.

3 and 4 show which structure a gas seal can have in the circumferential direction. To simplify the illustration, FIG. 4 is shown in the manner of a processing for FIG. 3. The circumferentially overlapping sealing parts 22 have strips 22a bent upwards in the axial direction and overlap in such a way that of the two circumferential edges of each sealing part 22, one edge lies above and one edge below the edge of an adjacent part . Only two of the sealing parts 22 overlap both edges of the adjacent sealing parts 22. These sealing parts are installed as the first and last part of the gas seal.

In the embodiment shown in Fig. 5, the gas seal in the radial direction is also divided into three sealing parts 23, 24 and 25. The inner sealing part 23 assigned to the layer 11 has a strip 23a bent upwards. The adjacent sealing part 24 has, on its side facing the sealing part 23, an approximately V-shaped strip 24a, which overlaps the strip 23a of the sealing part 23 or into which the strip 23a can be inserted.

The sealing part 24 has on its outer edge a strip 24b which is first bent downwards and then outwards, the horizontal part of which overlaps the horizontal part of a strip 25a of the sealing part 25 which is shaped in the same way. This overlap area is located in a groove-shaped recess 26 of approximately square cross-section, which is formed in the middle layer 12 of the lining and is filled with a sealing or filling compound in the form of mortar, fiber material or the like. In this embodiment there is a relatively large overlap area in the radial direction in which correspondingly large thermal expansions can be compensated for to a sufficient extent.

The outer sealing part 25 is fastened in the same way as in the exemplary embodiment according to FIG. 2 by means of a support ring 19, a seal 20 and a retaining ring 21.

6 shows a modified embodiment for the connection between two adjacent sealing parts 27 and 28. The sealing part 27 has a strip 27a bent in the axial direction, the free edge of which in turn is bent through 180 ° to form a sealing lip 27b. As a result, the edge of the sealing part 27 can better adapt to the shape of a strip 28a of the sealing part 28 which is bent into a V-shaped pocket. The free edge of the strip 28a is in turn bent back outwards by 180 ° in order to achieve greater strength in this area. The connection is also established here simply by plugging the sealing parts 27 and 28 into one another.

In the embodiment according to FIG. 7, two sealing parts 29 and 30 are not in direct contact with one another, but are connected to one another by a connecting part 31. The sealing part 29 has a strip 29a bent upwards in the axial direction. The connecting part 31 is connected to the sealing part 30 by two folds 30a and 31a. Following the fold 31 a, the connecting part 31 forms a second, likewise U-shaped part 31 b, which runs at approximately a right angle to the fold 31 a and surrounds the strip 29 a of the sealing part 29. The connecting part 31 is also designed and shaped here in such a way that the sealing part 29 can be inserted or removed in the axial direction. To improve the sealing effect in this area, a seal 32 can additionally be placed between the strips 29a and the surrounding U-shaped part 31b of the connecting part 31.

8 shows only the neighboring area between the two layers 11 and 12 of the lining. A layer 33 is assigned to the layer 11, which has a strip 33a which is bent upward approximately in the axial direction. The latter, in turn, is bent outwards at its free edge by 180 °. The same applies to a strip 34a of the same shape the sealing part 34 assigned to the layer 12. With the exception of the parts of the strips 33a and 34a bent back by 180 °, this embodiment of the gas seal is similar to the embodiment according to FIG. 2. However, the overlap area in the axial direction is now even greater.

In the embodiment shown in FIG. 9, only the layer 11 of the lining is divided in the axial direction above and below the gas seal. In the area of the layers 12 and 13, the upper lining section is supported on console stones 35 which are enclosed in a support ring 36 of L-shaped cross section. Instead of the console stones 35, a concrete ring that is continuous over the circumference or formed from segment-shaped parts can also be used. The support ring 36 lies over two seals 37 on a support bracket 38, which in turn is welded to the steel jacket 19.

A sealing part 39 assigned to the inner layer 11 and a sealing part 40 assigned to the other two layers 12 and 13 are connected to one another in the same way as, for example — the sealing parts 23 and 24 in the embodiment according to FIG. 5. The outer sealing part 40 is between the two seals 37 held clamped.

Claims (13)

1. A lining for a combustion chamber which is at least approximately round in cross-section and which is divided in the radial direction into at least two layers (11, 12, 13) and in the axial direction into at least two sections, having a gas seal comprising metal foil material, which has a sealing portion (16a, 17a; 23a, 24a; 27a, 28a; 29a, 31 b; 33a, 34a) which extends between two layers (11, 12,13) in the axial direction, and a sealing portion (16,17,18;23,24,25;27,28,29,30;33,34;39, 40) which in the boundary region between two layers (11, 12, 13) is bent away perpendicularly therefrom and which extends between two sections in a radial direction, characterised in that the sealing portions which extend in the radial and axial directions are connected to form a per se known gas seal which extends continuously from the insidetothe outside of the lining, in such a way that adjacent sealing portions extending in the radial direction overlap each other in the region between two layers (11, 12, 13) of the lining and are connected releasably in the axial direction in the manner of a plug connection.

2. A lining according to Claim 1, characterised in that the mutually overlapping axial sealing portions (16a, 17a; 17a, 18a; 33a, 34a) are arranged in a position of bearing against each other and laterally one beside the other between two layers (11,12,13).

3. A lining according to Claim 1 or 2, characterised in that the sealing portions (16, 17, 18) which extend in the radial direction are disposed at different axial positions in respect of height and the axially extending, mutually overlapping sealing portions (16a, 17a; 17a, 18a) bridge over the difference in height between two adjacent radially extending sealing portions.

4. A lining according to Claim 1, characterised in that at least one of the mutually overlapping axial sealing portions (23a, 24a, 27a, 28a) is bent back and the other sealing portion (23a, 27a) can be inserted into the fold formed by the bent-back configuration.

5. A lining according to Claim 3, characterised in that the fold is open downwardly.

6. A lining according to Claim 4 ou 5, characterised in that the fold is disposed at that one (28) of two adjacent radially extending sealing portions (27, 28) which is arranged higher in the axial direction than the other sealing portion (27) which can be fitted into the fold.

7. A lining according any of Claims 4 to 6, characterised in that the free edge of the sealing portion(27a) which can be fitted into the fold is folded back through 180° to form a sealing lip (27b, 27a).

8. A lining according to any of Claims 4 to 7, characterised in that the free edge of the part, which forms the fold, of the axially extending sealing portion (28a) is bent over towards the outside of the fold.

9. A lining according to one of the preceding claims, characterised in that a respective sealing portion (30) is made up of a radially extending ring segment and an axially extending strip (connecting portion 30) which are connected together by folding (fig. 7).

10. A lining according to one of the preceding claims, characterised in that the most outwardly disposed sealing portion (18) is arranged with its outer edge between a support ring (19) and a holding ring (21) and the rings are screwed together.

11. A lining according to one of the preceding claims, characterised in that the layers (12, 13) of the lining of at least one section are supported on an annular support bracket (38) and the outer edge of the outer sealing portion (40) is clampingly held between the lining and the support bracket (38).

12. A lining according to one of the preceding claims, characterised in that the gas seal (14) is also divided in the peripheral direction into a plurality of sealing portions (22) whose end regions, which face towards each other in the peripheral direction, overlap each other.

13. A lining according to Claim 12, characterised in that, of the two end regions of a sealing portion (22), one lies above and one lies belowthe end region of respective adjacent sealing portions, and that at least one of the sealing portions (22) has both end regions overlapping the adjacent sealing portions.

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