GRATE BLOCK FOR A COMBUSTION GRATE

Abstract

A grate block for a combustion grate including a block body having an upper wall which forms a bearing surface and along which the combustible material is to be conveyed and a front wall which has a lower bearing edge, the bearing edge being designed to come into contact with the bearing surface of an adjacent grate block in a feed direction, wherein the upper wall has an air supply opening formed by an air supply channel. The air supply opening is at least partially surrounded by a thickened portion which protrudes from the bearing surface, forms a protective channel extending the air supply channel, and is designed to prevent liquid from flowing into the air supply opening.

Claims

1. A grate block for a combustion grate, wherein the grate block comprises a block body that has an upper wall and defines a longitudinal axis, wherein the upper wall forms a bearing face along which the incinerator charge is to be conveyed and the foremost end of which, when viewed in a thrust direction, aligned substantially parallel to the longitudinal axis, forms an edge by way of which the bearing face descends into a thrust surface formed by a front wall, the front wall has a lower bearing edge which is disposed in a plane running substantially orthogonally to the longitudinal axis and specified for coming into contact with the bearing face of a grate block adjacent in the thrust direction, wherein the upper wall has an air supply opening formed by an air supply duct running through the upper wall, wherein the air supply opening is at least partially surrounded by a thickening which projects from the bearing face and forms a protection duct, which extends the length of the air supply duct, and is specified to prevent liquid flowing into the air supply opening, wherein the protection duct is enclosed by an inner flank of the thickening and the thickening has an outer flank that adjoins the inner flank and runs in a descending manner on the side that faces away from the protection duct.

2. The grate block as claimed in claim 1, wherein the inner flank is formed so as to be adjacent to a periphery of the air supply opening that is configured in the bearing face.

3. The grate block as claimed in claim 1, wherein the cross section of the protection duct is configured so as to widen in the direction from the end of the protection duct that faces away from the bearing face to the bearing face.

4. The grate block as claimed in claim 1, wherein the cross section of the air supply duct widens in the direction away from the bearing face.

5. The grate block as claimed in claim 1, wherein the thickening has substantially the shape of a hollow truncated cone.

6. The grate block as claimed in claim 1, wherein the thickening, when viewed in a plane plane running parallel to the bearing face, has a U-shape or V-shape, wherein the opening of the U-shape or the V-shape is aligned in the transport direction.

7. The grate block as claimed in claim 1, wherein the thickening is welded or mechanically fastened to the grate block.

8. The grate block as claimed in claim 1, wherein the thickening is formed so as to be integral to the grate block.

9. A combustion grate comprising at least one grate block as claimed in claim 1.

10. A method comprising applying a combustion grate as claimed in claim 9 for the incineration of waste.

11. A waste incineration plant comprising a combustion grate as claimed in claim 9.

12. A method for producing a grate block as claimed in claim 1, wherein a) a block body configured as a casting, having an upper wall and defining a longitudinal axis is provided, wherein the upper wall forms a bearing face along which the incinerator charge is to be conveyed and the foremost end of which, when viewed in a thrust direction, aligned substantially parallel to the longitudinal axis, forms an edge by way of which the bearing face descends into a thrust surface formed by a front wall, the front wall has a lower bearing edge which is disposed in a plane running substantially orthogonally to the longitudinal axis and specified for coming into contact with the bearing face of a grate block adjacent in the thrust direction, wherein the upper wall has an air supply opening formed by an air supply duct running through the upper wall, and the bearing face about the air supply opening is configured so as to be substantially planar, and b) the thickening is welded or mechanically fastened about the air supply opening.

13. A method for producing a grate block as claimed in claim 1, wherein a replacement thickening after abrasion of at least 50% of the height of the thickening, caused by the operation of the grate block, for restoring the thickening is welded or mechanically fastened.

14. A molded part for fastening to an upper wall of a block body of a grate block about an air supply opening which is configured in the upper wall and formed by an air supply duct extending through the upper wall, wherein the grate block is specified for a combustion grate and the block body is configured as a casting, wherein the upper wall forms a bearing face along which the incinerator charge is to be conveyed, wherein the molded part, in the fastened state, forms a thickening that projects from the bearing face, surrounds the air supply opening, forms a protection duct, which extends the length of the air supply duct, and is specified for preventing liquid flowing into the air supply opening, wherein the protection duct is enclosed by an inner flank of the thickening and the thickening has an outer flank that adjoins the inner flank and runs in a descending manner on the side that faces away from the protection duct.

15. The molded part as claimed in claim 14, wherein the cross section of the protection duct widens in the direction from the end of the protection duct that faces away from the bearing face to the bearing face.

16. The molded part as claimed in claim 14, wherein substantially the shape of a hollow truncated cone.

17. The molded part as claimed in claim 14, comprising a fastening means for mechanical fastening to the upper wall.

Description

[0101] The invention will be illustrated by means of the appended figures, in which:

[0102] FIG. 1 shows a grate block according to the invention in a perspective view; and

[0103] FIG. 2 shows a detail of the grate block according to FIG. 1 in the longitudinal section through the sectional plane II-II shown in FIG. 1, wherein the thickening is configured so as to be integral to the grate block;

[0104] FIG. 3 shows a detail of the grate block according to FIG. 1 in the longitudinal section through the sectional plane II-II shown in FIG. 1, wherein the thickening is welded to the grate block;

[0105] FIG. 4 shows a detail of a further grate block according to the invention in the longitudinal section, wherein a molded part is mechanically fastened to an upper wall of the grate block;

[0106] FIG. 5 shows a longitudinal section of the molded part according to FIG. 4 without a grate block; and

[0107] FIG. 6 shows a longitudinal section of the upper wall of the grate block according to FIG. 4 without a molded part.

[0108] As can be seen from FIG. 1, the grate block 10 comprises a block body 12 configured as a casting, which is configured substantially in the form of an elongate cuboid with a longitudinal axis L.

[0109] The block body 12 comprises an upper wall 14, which forms a bearing face 16 running parallel to the longitudinal axis L, along which the incinerator charge is to be conveyed and the foremost end of which, when viewed in the thrust direction S, forms an edge 19, over which the bearing face 16 descends into a thrust face 22 formed by a front wall 20.

[0110] In the embodiment shown, the bearing face has a first bearing face region 16a and a second bearing face region 16b, both of which run parallel to the longitudinal axis L, but the first bearing face region 16a is disposed offset upward from the second bearing face region 16b and connected via a beveled transition 17 to the latter.

[0111] On the side opposite the front wall 20, the block body 12 has a rear wall 24 which is equipped with at least one hook 26 with which the grate block 10 can be hooked into a block mounting tube. A central web 29 is also disposed on the underside of the grate block 10 that faces away from the bearing face 16.

[0112] Laterally, the grate block 10 is in each case closed off by a lateral wall 28a, 28b extending in the longitudinal direction L.

[0113] Within the combustion grate, the grate block 10 bears on a grate block that follows in the thrust direction S. For this purpose, the lowermost area of the front wall 20 is configured in the form of a block 34, which is specified to rest on the bearing face of a grate block adjacent in the thrust direction S. The lowermost area including a front bearing edge 23 of the thrust surface formed by said lowermost area is disposed in a plane E which runs substantially orthogonally to the longitudinal axis L.

[0114] As can be seen from FIG. 2, the upper wall 14 also has an air supply opening 35 which is formed by an air supply duct 38 extending through the upper wall 14. Primary air is supplied to the combustion grate or the combustion bed on the combustion grate through the air supply duct 38.

[0115] In the embodiment shown, the air supply duct 38 forms a slot-shaped air supply opening 35 in the upper wall 16, which is aligned in the longitudinal direction of the grate block 10, and the air supply duct 38 defines a longitudinal plane of symmetry P. In FIG. 2, the section plane II-II runs in the longitudinal plane of symmetry P.

[0116] The air supply duct 38 extends concentrically to an axis R running orthogonally to the bearing face 16 and in the longitudinal plane of symmetry P, the available opening of the air supply duct 38 being substantially elliptical and expanding continuously in the direction away from the bearing face 16 in the form of a cone. The air supply duct comprises a first air supply duct portion 38a that faces the bearing face 16 and a second air supply duct portion 38b adjoining the first air supply duct portion 38a on its side that faces away from the bearing face, wherein the widening of the second air supply duct portion 38b is greater than the widening of the first air supply duct portion 38a. With respect to the axis R, the generatrix of the cone forms a first angle of 10 degrees in the first air supply duct portion 38a and a second angle of 15 degrees in the second air supply duct portion 38b.

[0117] Furthermore, the air supply opening 35 is completely surrounded by a thickening 50 projecting from the bearing face 16. The thickening 50 forms a protection duct 57, which extends the air supply duct 38, and is specified to prevent liquid flowing into the air supply opening 35.

[0118] The protection duct 57 comprises a lower protection duct opening 57a on the end of the protection duct 57 that faces the bearing face 16 and an upper protection duct opening 57b on the end of the protection duct 57 that faces away from the bearing face 16, i.e. on the side of the thickening that faces the incinerator charge.

[0119] Furthermore, the protection duct 38 is enclosed by an inner flank 54 of the thickening 50, wherein the inner flank 54 is configured so as to be directly adjacent to a periphery of the air supply opening 58 running in the bearing face. In addition, the thickening 50 has an outer flank 55 which adjoins the inner flank 54, descends on the side that faces away from the protection duct 38 and runs in a rectilinear manner. A flattened transition region 60 of the thickening 50 also extends between the inner flank 54 and the outer flank 55. In the embodiment shown, the height h of the thickening, when measured from the bearing face, is approx. 20 mm. In addition, the inner flank, when viewed in cross section, runs at least approximately in the extension of the lateral surface of the first air supply duct portion 38a.

[0120] In FIG. 2, the thickening 50 in a casting method is formed so as to be integral to the grate block 10.

[0121] In FIG. 3, the grate block according to FIG. 1 is shown, wherein the thickening is formed by a molded part 50′ and welded to the grate block 10. Accordingly, the grate block 10 has a weld seam 70 at the interface between the molded part 50′ and the bearing face 16. The molded part 50′ has substantially the shape of a truncated cone which has an elliptical base area and which extends concentrically to the axis R. Furthermore, the molded part 50′ comprises a protection duct 57 which extends concentrically to the axis R and is specified to extend the length of the air supply duct 38. The protection duct 57 is configured in such a manner that its inner flank 54 runs in the extension of the lateral surface of the air supply duct 38.

[0122] The other features of the detail of the grate block 10 shown in FIG. 3 are similar to those in FIG. 2 and can be derived from the corresponding description.

[0123] In operation, the grate blocks 10 are moved relative to one another by means of the block mounting tubes. Depending on whether the block mounting tubes are assigned to a stationary or a movable grate block, the block mounting tubes are either attached to stationary consoles or to consoles which are disposed in a movable grate carriage.

[0124] Driving takes place by hydraulic cylinders which move the grate carriages back and forth over rollers on corresponding running surfaces.

[0125] Due to the relative movement obtained in this way, the foot 34 of a first grate block 10 is pushed back and forth over the bearing face 16 of the respectively subsequent grate block 10, wherein the incinerator charge is conveyed over the bearing face 16 before said incinerator charge is dropped over the edge 19 onto the bearing face 16 of the subsequent grate block 10.

[0126] Illustrated in FIG. 4 is a detail of a grate block 10 according to the invention, wherein the thickening is formed by a molded part 50′ and mechanically fastened to the grate block 10. The grate block 10 comprises a block body 12 which in terms of construction has the same features as the grate block of FIG. 1. Only the differences will be described in more detail hereunder and the same parts are identified by the same reference symbols.

[0127] The block body 12 has a recess 72 extending about the air supply opening 35. In the present case, the air supply opening 35 and the recess 72 are configured to be rotationally symmetrical about an axis Q running orthogonally to the bearing face 16 and defined by the air supply opening 35. The recess 72 has a tapering section, i.e. a constriction, in the form of a lip 74, which adjoins the bearing face 16.

[0128] The molded part 50′ has substantially the shape of a hollow truncated cone having an elliptical base area, as can be seen in FIGS. 4 and 5. On the side of the molded part that faces away from the incinerator charge, the molded part has a base 80 penetrated by the air supply duct, the outer base area 82 of which coincides with the base area of the truncated cone. In the embodiment shown in FIG. 4, in the fastened state of the molded part, the outer base area 82 runs at least flush with the plane of the bearing face 16.

[0129] Furthermore, the molded part 50′ comprises a fastening means in the form of a protrusion 84, which projects from the base 80 of the molded part, in the direction away from the side of the molded part that faces the incinerator charge. The protrusion 84 is frustoconical and rotationally symmetrical to the axis Q. The protrusion 84 is specified to be received in the recess 72 and held by a mechanical connection.

[0130] For this purpose, the largest cross section of the widening section of the protrusion 84 is of larger dimension than the smallest cross section of the constriction 74, in such a manner that the protrusion 84 can be pressed and inserted into the recess 72. As a result, the protrusion 84 remains clamped in the recess 72.

LIST OF REFERENCE SIGNS

[0131] Grate block 10 [0132] Block body 12 [0133] Upper wall 14 [0134] Bearing face 16 [0135] Bearing face region 16a, 16b [0136] Transition 17 [0137] Edge 19 [0138] Front wall 20 [0139] Rear wall 24 [0140] Hook 26 [0141] Lateral wall 28a, 28b [0142] Central web 29 [0143] Block 34 [0144] Air supply opening 35 [0145] Air supply duct 38 [0146] First and second air supply duct portion 38a, 38b [0147] Thickening or molded part 50, 50′ [0148] Inner flank 54 [0149] Outer flank 55 [0150] Protection duct 57 [0151] Lower and upper protection duct opening 57a and 57b [0152] Periphery of the air supply opening 58 [0153] Transition region 60 [0154] Weld seam 70 [0155] Front wall plane E [0156] Longitudinal axis L [0157] Thrust direction S [0158] Longitudinal plane of symmetry P [0159] Axis R [0160] Height of the thickening h [0161] Recess 72 [0162] Lip 74 [0163] Base 80 [0164] Base area 82 [0165] Protrusion 84 [0166] Axis Q