JP7830768B2 - Grate track boundary elements for combustion grates - Google Patents

Description

The present invention relates to a grate track boundary element for a combustion grate for burning waste, and to a combustion grate comprising at least one such grate track boundary element of this type.

Combustion grates for burning waste on an industrial scale have long been known to those skilled in the art. Such combustion grates can exist, for example, in the form of a thrust combustion grate including a movable part to perform a stoking stroke. In this case, the material to be burned is transported in a transport direction from the inlet end to the outlet end of the combustion grate, and is burned along the way. To supply the combustion grate with the oxygen necessary for combustion, corresponding air supply sections are provided that penetrate the combustion grate. Air, also called primary air, is introduced through these air supply sections.

A commonly used combustion grate is the so-called stepped grate. Such a stepped grate includes grate blocks arranged side-by-side. Each of these grate blocks forms a row of grate blocks. In this case, the rows of grate blocks are arranged in a stepped fashion, vertically relative to each other. In the case of a so-called movable grate, the front end of one grate block, viewed in the thrust direction, rests on the support surface of the adjacent (lower) grate block in the transport direction, and is moved on this support surface during corresponding thrust movements.

During combustion, or due to the high temperature inside the combustion chamber, the grate block is subjected to an extremely high thermal load. This thermal load accelerates erosion due to abrasion and erosion caused by chemical reactions on the support surfaces, further damaging them. All of this ultimately shortens the service life of the grate block.

To reduce the heat load, the grate bars are usually cooled from below with a cooling medium or fluid, i.e., on the opposite side of the combustion grate from the combustion side. Water or air is typically used as the cooling medium. Therefore, air-cooled or water-cooled grate blocks are also frequently mentioned.

The grate tracks expand due to the heat load generated during combustion and contract again when the moving grate of the moving grate furnace comes to a standstill. Therefore, each grate track is positioned to expand at least longitudinally. This deformation of the components and/or the creation of voids, through which uncontrolled primary air enters the combustion chamber, can cause problems. Such primary air promotes uncontrolled combustion, which further increases the heat load.

In the case of a two-track forward grate, or a forward grate with multiple rows of two-track grate tracks arranged side by side, a grate track separation section is formed in the center, consisting of individual grate separation elements fixed between the two grate tracks. This grate track separation section is also called the central beam.

The bonding support disclosed in Patent Document 1 is specified to ensure thermal expansion compensation and sealing of the space between two laterally joined grate tracks.

The grate track separation element disclosed in Patent Document 2 is formed from a single cast portion. Due to its configuration as a single-piece element, the grate track separation element can only absorb the lateral expansion of the grate track in a limited manner. This can lead to the aforementioned voids, potentially causing primary air to unintentionally enter the combustion chamber.

German Patent No. 69105120 International Publication No. 2018/149516

Therefore, the object of the present invention is to provide a grate track boundary element that eliminates the drawbacks of the prior art, compensates for the thermal expansion of the grate track, and consequently prevents the uncontrolled outflow of primary air into the combustion chamber.

These problems are solved according to the present invention by the grate block described in claim 1, the combustion grates described in claims 12 and 13, and the combustion equipment described in claim 15. Preferred embodiments of the present invention are shown in the dependent claims.

This invention relates to a grate track boundary element for a combustion grate for burning waste. The grate track boundary element includes a flow channel element and a flow channel cover for covering the flow channel element. The flow channel cover includes at least one cover element and a terminal connection element equipped with a locking device. The terminal connection element has a support surface oriented away from the flow channel element and a first engaging element oriented toward the cover element. The cover element includes a support surface oriented away from the flow channel element, a retaining element oriented toward the flow channel element, a second engaging element oriented toward the terminal connection element and formed to accommodate the first engaging element, and a recess oriented toward the terminal connection element for accommodating the locking device of the terminal connection element. The locking device is formed to removably lock the terminal connection element within the flow channel element.

In the context of this invention, the concept of an "engaging element" is understood to be an element that engages with another element, or is engaged with another element within itself. Therefore, for example, both the nose and the recess for such a nose are referred to as engaging elements.

The advantage of the grate track boundary element according to the present invention over conventional solutions is that the expansion of the grate track is compensated for by the compression of the flow channel element. This results in better sealing of the entire structure and, consequently, less uncontrolled inflow of primary air into the combustion chamber. Structures with fixed covers, as described in International Publication No. 2018/149516, do not provide the same improved sealing. This is because the expansion of the grate track cannot be compensated for as effectively due to the low elasticity of the "integrated" flow channel element.

In a preferred embodiment of the grate track boundary element, the flow path cover includes a second cover element, which is preferably formed identically to the first cover element.

When fixing the flow path cover, a compromise is preferably chosen between the number of individual parts to be assembled and the weight of those individual parts. In embodiments where the cover elements are uniformly distributed around the terminal connection elements, the cover elements become relatively heavy, or the effort required to fix the terminal connection elements increases. For heavy covers that cover a larger area of the flow path elements, two assemblers are required to position the cover elements together on the flow path elements. Furthermore, the effort required to fix the terminal connection elements should not be underestimated. It is advantageous for a row of two preferably identically formed cover elements to be fixed by a single terminal connection element. This results in lighter individual parts, easier assembly, and a reduced number of terminal connection elements, which in turn reduces the effort required to fix the terminal connection elements.

Preferably, the first engaging element is formed as a projection, and the second engaging element is formed as a recess. Therefore, the engaging elements may be formed as projections or as recesses for accommodating projections. In a preferred embodiment, the cover element includes one engaging element each formed as a recess, and the cover element includes an engaging element formed as a projection (also known as a nose). This engaging element is formed to fit into a notch in the cover element. In a further preferred embodiment, the terminal connection element includes two engaging elements formed as projections, facing each other. Each of these engaging elements engages into a recess in the cover element.

This structure allows the flow channel cover to be fixed within the flow channel element in an improved state. This enhances the sealing performance of the grate track boundary element.

In a preferred embodiment of the grate track boundary element, the flow channel element includes an opening oriented toward the flow channel cover for accommodating a retaining element of the cover element. The opening is formed as a groove with a notch, and is narrower than the width of the retaining element. Alternatively, the notch may be wider than the width of the retaining element of the cover element.

In the context of this invention, a groove with a notch is understood to mean a longitudinal opening parallel to the longitudinal axis of the flow path element. This opening has locally expanded portions (notches), and these expanded portions are wider than the groove.

This preferred structure allows the cover element and terminal connector element to be inserted into the flow path element at the notch location and subsequently slid to the final assembly location. Such a structure facilitates the assembly and removal of the cover element and terminal connector element without compromising their sealing ability.

Preferably, the flow path element includes a cooling fluid channel with a cooling fluid inlet and a cooling fluid outlet. This allows the flow path element to be cooled by incorporating the fluid channel or by utilizing the flow path element as a fluid channel. This reduces wear on the grate track boundary element and, consequently, extends its useful life.

In a preferred embodiment of the grate track boundary element, the opening of the flow channel element, oriented toward the flow channel cover, extends into the fluid flow channel. Such a preferred structure facilitates the production of individual elements, thereby reducing the cost of the elements and, consequently, the cost of the entire system.

Preferably, the grate track boundary element includes a sealing element laterally attached to the wall of the flow path element. Such a sealing element enhances the sealing performance of the grate and reduces uncontrolled inflow of primary air into the combustion chamber.

A forward grate typically includes movable and non-movable grate blocks. These grate blocks are arranged to form rows of movable and non-movable grate blocks. While rows of non-movable grate blocks compress the grate track boundary elements due to thermal expansion, this is not the case to the same extent for rows of movable grate blocks, because such rows of movable grate blocks must remain movable. Therefore, it is preferable that sealing elements be attached to the grate track boundary elements above the contact points of the grate blocks, and it is particularly preferable that such sealing elements be attached only above the movable grate blocks.

In a preferred embodiment of the grate track boundary element, the support surface of the cover element facing away from the flow channel element, and the support surface of the terminal connection element facing away from the flow channel element, are formed in a gable roof shape or mansard gable roof shape, preferably with rounded edges.

In the context of this invention, the concept of a gable roof refers to a shape similar to a gable roof. That is, a shape in which the roof surface descends on both sides of a gable oriented in the longitudinal direction. In the context of this invention, a mansard gable roof is understood to refer to a specific shape of a gable roof, in which the roof surface descending from the gable laterally does not extend as a flat plane, but is divided into multiple planes, each with a different slope.

Further preferred embodiments of the support surfaces of the cover element and terminal connection element, oriented away from the flow path element, are semicircular, elliptical, or flat planes.

The preferred embodiment of the support surface described above is particularly efficient when transporting and distributing the combustible material on the combustion grate, and it has been found that this prevents the combustible material from remaining on the grate track boundary elements.

Preferably, the locking device is formed as a clamp, and the clamp is particularly preferably positioned between the support surface of the terminal connection element and the flow path element.

Such preferred embodiments of the locking device allow for simple assembly and disassembly, as well as high stability of fixation, thus enabling stable fastening of the terminal connection element while also allowing for easy assembly and disassembly.

By positioning the clamp below the support surface, it is protected from direct contact with the material being combusted. This prevents the clamp from being blocked or obstructed by the material, thus allowing for easy assembly and disassembly.

In a more preferred embodiment, the locking device is designed as a stud with a locking pin, a screw with or without a nut, or a spreader element. All embodiments allow the locking device to be removed with minimal effort to remove the terminal connecting element. Even for embodiments where the locking device is formed as a stud with a locking pin, a screw with or without a nut, or a spreader element, it is preferable that the locking device be positioned below the support surface to protect it from direct contact with the material to be combusted.

In a preferred embodiment of the grate track boundary element, the support surface of the cover element facing away from the flow channel element, and the support surface of the terminal connection element facing away from the flow channel element, are formed in a single-slope roof shape.

In the context of this invention, the concept of a single-slope roof refers to a shape similar to a single-slope roof. In a single-slope roof, one side of the roof slopes from the gable at an angle of 10 to 80 degrees, while the other side of the roof slopes vertically or nearly vertically. Such embodiments are advantageous if the grate track boundary elements extend along the walls of the combustion chamber.

The advantage of a support surface formed in a single-slope roof shape is that the material to be burned does not remain to the sides, preferably against the side walls of the combustion chamber, thereby potentially causing uncontrolled combustion.

Preferably, the locking mechanism includes a plate and a stud for securing the plate within the terminal connecting element. This allows for simple installation and removal in a grate track boundary element that can be axled from only one side, i.e., a grate track boundary element extending along the wall of a combustion chamber.

The present invention further relates to a combustion grate comprising at least two grate tracks and the aforementioned grate track boundary elements positioned between the grate tracks.

The advantage of the combustion grate according to the present invention is, as described above, that the inflow of controlled combustion air into the combustion chamber is prevented.

The present invention further relates to a combustion grate having at least one grate track, and the aforementioned grate track boundary element disposed between the grate track and the side wall of the combustion chamber of the combustion equipment.

The advantages of the combustion grate according to the present invention are, as described above, that the inflow of controlled combustion air into the combustion chamber is prevented, and that the material to be burned does not remain along the side walls.

The present invention further relates to a combustion apparatus for heat-treating waste, comprising one or more combustion grates as described above.

The advantages of the combustion equipment according to the present invention are, as described above, that the inflow of controlled combustion air into the combustion chamber is prevented, thereby enabling more efficient combustion of waste and requiring less maintenance of the equipment.

Based on several embodiments shown in the drawings, the present invention is described in detail below. Where alternative embodiments differ only in individual features, the same reference numerals are used for the same features. The drawings are purely schematic.

Figure 1 is a perspective view showing the combustion chamber of the combustion equipment. Figure 2 is a perspective view showing a combustion grate with grate track boundary elements. Figure 3 is a perspective view showing the grate track boundary elements of Figure 2. Figure 4 is an exploded view showing the grate track boundary elements of Figure 3. Figure 5 is a perspective view showing an embodiment of the flow path cover. Figure 6 is a bottom view showing an embodiment of the cover element. Figure 7 is a bottom view showing an embodiment of the terminal connection element. Figure 8 is a perspective view showing a combustion grate with grate track boundary elements. Figure 9 is a longitudinal cross-sectional view showing the combustion grate in Figure 8. Figure 10 is a perspective view showing the grate track boundary elements of Figure 8. Figure 11 is an exploded view showing the grate track boundary elements of Figure 10. Figure 12 is a detailed view showing a sealing element attached to the wall of a flow channel element on the side.

The combustion chamber 1 of the combustion equipment shown in Figure 1 includes a side wall 3 and a combustion grate 5 containing an air-cooled grate track 7 and a water-cooled grate track 9. Furthermore, the combustion grate 5 includes two grate track boundary elements 11 and 13.

Figure 2 shows a combustion grate 5 that includes an air-cooled grate track 7, a water-cooled grate track 9, and a grate track boundary element 11 positioned between the two grate tracks.

Figure 3 shows a grate track boundary element 11, which includes a flow channel element 15, a flow channel cover 17, and a sealing element 19.

Figure 4 shows a grate track boundary element 11 with a raised channel cover 17. The channel cover 17 consists of two cover elements 21 and 23 and one terminal connection element 25. The channel element 15 includes a groove 27 extending in the longitudinal direction of the channel element 15. This groove 27 has a notch 29.

Figure 5 is a detailed view showing a flow path cover 17 including cover elements 21, 23 and a terminal connection element 25. The cover elements 21, 23 include retaining elements 31, 32. These retaining elements are located on the side of the cover elements 21, 23 facing the flow path element 15. On the side opposite to the flow path element 15, the cover elements 21, 23 have support surfaces 33, 35. The material to be combusted is placed on these support surfaces. In this embodiment, the support surfaces 33, 35 are formed in a mansard gable roof shape with rounded edges. Furthermore, the cover elements 21, 23 have engaging elements 37, 39. These engaging elements are formed here as recesses. The engaging elements 37, 39 are oriented toward the terminal connection element 25. Below the engaging elements 37, 39, the cover elements 21, 23 each have one recess 41, 43 (the recess 43 is not visible in the cover element 23 in this figure). The recess 41 serves to accommodate a locking device (described later). Figure 5 further shows a terminal connection element 25 comprising a support surface 45 and two engaging elements 47, 49 formed as projections. Furthermore, the terminal connection element 25 includes a locking device 51, which is formed as a clamp.

Figure 6 is a bottom view showing cover elements 21 and 23, which include retaining elements 31 and 32, recesses 41 and 43, and an engaging element 39 (engaging element 37 is not visible).

Figure 7 is a bottom view showing a terminal connecting element 25 equipped with an engaging element 47 and a locking device 51 .

Figure 8 is a detailed view showing a combustion system comprising a side wall 3, a combustion grate 5 having an air-cooled grate track 7, and a grate track boundary element 13 positioned between the side wall 3 and the grate track 7.

Figure 9 is a longitudinal cross-sectional view showing the combustion apparatus of Figure 8, comprising a side wall 3, a combustion grate 5, an air-cooled grate track 7, and a grate track boundary element 13 positioned between the side wall 3 and the grate track 7.

Figure 10 is a detailed view showing a grate track boundary element 13 comprising a flow path element 15 having a sealing element 19 mounted on the side, and a flow path cover 17 including cover elements 21, 23 and a terminal connection element 25.

Figure 11 is a detailed view showing a flow path cover 17 with cover elements 21, 23 and a terminal connection element 25. The support surfaces 33, 35 of the cover elements 21, 23 are formed here in a single-slope roof shape with rounded edges. The cover elements 21, 23 have retaining elements 31, 32 on the side facing the flow path element 15. Furthermore, the cover elements 21, 23 include engaging elements 37, 39 on the side facing the terminal connection element 25. These engaging elements are formed here as recesses. In addition, the cover elements 21, 23 include recesses 41, 43 (recess 41 is not visible) for accommodating a locking device 51. Figure 11 further shows the terminal connection element 25 with the locking device 51. This locking device 51 is formed here as a plate with studs.

Figure 12 is a detailed view showing the transition from the grate track boundary element 13 to the combustion grate 5. The flow path element 15 is located laterally and includes a sealing element 19 attached to the flow path element 15. The sealing element 19 is mounted above a row of movable grate blocks. These movable grate blocks move back and forth on the sliding surface 53 of the non-movable grate block 55. The sealing element 19 closes the seams (not shown) that occur when the combustion grate 5 contracts, i.e., the seams through which primary air could reach the combustion chamber uncontrolled.
The following are some embodiments (configurations) of the present invention.
[Aspect 1]
A grate track boundary element (11, 13) for a combustion grate (5) for burning waste,
Flow channel element (15),
A flow path cover (17) for covering the flow path element (15), including at least one cover element (21, 23) and a terminal connecting element (25) equipped with a locking device (49),
Equipped with,
The terminal connection element (25) has a support surface (45) facing away from the flow path element (15) and first engagement elements (47, 49) oriented toward the cover elements (21, 23).
The cover element (21, 23) has a support surface (33, 35) facing away from the flow channel element (15), a retaining element (31, 32) oriented toward the flow channel element (15), a second engaging element (37, 39) oriented toward the terminal connecting element (25) and formed to accommodate the first engaging element (47, 49), and a recess (41, 43) oriented toward the terminal connecting element (25) for accommodating the locking device (49) of the terminal connecting element (25),
The locking device (49) is a grate track boundary element (11, 13) formed to removably lock the terminal connecting element (25) within the flow path element (15).
[Aspect 2]
The grate track boundary element (11, 13) according to embodiment 1, characterized in that the flow path cover (17) includes a second cover element (21, 23), and the second cover element is preferably formed identically to the first cover element (21, 23).
[Aspect 3]
The grate track boundary elements (11, 13) according to embodiment 1, characterized in that the first engaging elements (47, 49) are formed as protrusions and the second engaging elements (37, 39) are formed as recesses.
[Aspect 4]
The flow channel element (15) includes an opening (27) oriented toward the flow channel cover (17) for accommodating the retaining elements (31, 32) of the cover elements (21, 23), the opening (27) being formed as a groove (28) with a notch (29),
The grate track boundary elements (11, 13) according to any one of embodiments 1-3, characterized in that the groove (28) is narrower than the width of the retaining elements (31, 32), and the notch (29) is formed wider than the width of the retaining elements (31, 32) of the cover elements (21, 23).
[Aspect 5]
The grate track boundary element (11, 13) according to any one of embodiments 1-4, characterized in that the flow channel element (15) includes a cooling fluid channel having a cooling fluid inlet and a cooling fluid outlet.
[Aspect 6]
The grate track boundary elements (11, 13) according to embodiment 5, characterized in that the opening (27) of the flow channel element (15), which is oriented toward the flow channel cover (17), extends into the cooling fluid flow channel.
[Aspect 7]
The grate track boundary elements (11, 13) according to any one of embodiments 1-6, characterized in that the grate track boundary elements (11, 13) include a sealing element (19) attached laterally to the wall of the flow channel element (15).
[Paragraph 8]
The support surfaces (33, 35, 45) of the cover elements (21, 23) and the terminal connection element (25), which face away from the flow path element (15), are formed in a gable roof shape or mansard gable roof shape, preferably with rounded edges, as described in any one of embodiments 1-7, for the grate track boundary elements (11, 13).
[Aspect 9]
The grate track boundary element (11, 13) according to any one of embodiments 1-8, characterized in that the locking device (49) is formed as a clamp, and the clamp is preferably positioned between the support surface (45) of the terminal connecting element (25) and the flow path element (15).
[Aspect 10]
The grate track boundary elements (11, 13) according to any one of embodiments 1-7, characterized in that the support surfaces (33, 35, 45) of the cover elements (21, 23) and the terminal connection element (25) that face away from the flow path element (15) are formed in a single-slope roof shape.
[Phenomenon 11]
The grate track boundary element (11, 13) according to any one of embodiments 1-7 and 10, characterized in that the locking device (49) includes a plate and a stud for fixing the plate within the terminal connecting element (25).
[Aspect 12]
A combustion grate (5) comprising at least two grate tracks (7, 9) and a grate track boundary element (11) positioned between the at least two grate tracks (7, 9) as described in any one of embodiments 1-9.
[Aspect 13]
A combustion grate (5) comprising at least one grate track (7) and a grate track boundary element (13) according to any one of embodiments 1-7, 10, and 11, positioned between the at least one grate track (7) and the side wall (3) of the combustion chamber of the combustion equipment.
[Aspect 14]
A combustion apparatus for heat-treating waste, comprising one or more combustion grates (5) as described in either aspect 12 and/or 13.

Claims (15)

A grate track boundary element (11, 13) for a combustion grate (5) for burning waste,
Flow channel element (15),
A flow path cover (17) for covering the flow path element (15), including at least one cover element (21, 23) and a terminal connecting element (25) equipped with a locking device ( 51 ),
Equipped with,
The terminal connection element (25) has a support surface (45) facing away from the flow path element (15) and first engagement elements (47, 49) oriented toward the cover elements (21, 23).
The cover element (21, 23) has a support surface (33, 35) facing away from the flow channel element (15), a retaining element (31, 32) oriented toward the flow channel element (15), a second engaging element (37, 39) oriented toward the terminal connecting element (25) and formed to accommodate the first engaging element (47, 49), and a recess (41, 43) oriented toward the terminal connecting element (25) for accommodating the locking device ( 51 ) of the terminal connecting element (25),
The locking device ( 51 ) is formed to removably lock the terminal connecting element (25) within the flow path element (15) and is a grate track boundary element (11, 13). The fire grate track boundary element (11, 13) according to claim 1, characterized in that the flow path cover (17) includes a second cover element (21, 23), and the second cover element is preferably formed identically to the first cover element (21, 23). The grate track boundary element (11, 13) according to claim 1, characterized in that the first engaging element (47, 49) is formed as a projection, and the second engaging element (37, 39) is formed as a recess. The flow channel element (15) includes an opening (27) oriented toward the flow channel cover (17) for accommodating the retaining elements (31, 32) of the cover elements (21, 23), the opening (27) being formed as a groove (28) with a notch (29),
The grate track boundary elements (11, 13) according to any one of claims 1 to 3, characterized in that the groove (28) is narrower than the width of the retaining elements (31, 32), and the notch (29) is formed wider than the width of the retaining elements (31, 32) of the cover elements (21, 23). The aforementioned flow path element (15) is characterized by including a cooling fluid flow path with a cooling fluid inlet and a cooling fluid outlet, as described in any one of claims 1-3, for the grate track boundary element (11, 13). The grate track boundary element (11, 13) according to claim 5, characterized in that the opening (27) of the flow channel element (15), which is oriented toward the flow channel cover (17), extends into the cooling fluid flow channel. The grate track boundary elements (11, 13) according to any one of claims 1 to 3, characterized in that the grate track boundary elements (11, 13) include a sealing element (19) laterally attached to the wall of the flow channel element (15). The support surfaces (33, 35, 45) of the cover elements (21, 23) and the terminal connection element (25), which face away from the flow path element (15), are formed in a gable roof or mansard gable roof shape, preferably with rounded edges, as described in any one of claims 1-3. The grate track boundary element (11, 13) according to any one of claims 1 to 3, characterized in that the locking device ( 51 ) is formed as a clamp, and the clamp is preferably positioned between the support surface (45) of the terminal connecting element (25) and the flow path element (15). The support surfaces (33, 35, 45) of the cover elements (21, 23) and the terminal connection element (25), which face away from the flow path element (15), are formed in a single-slope roof shape, as described in any one of claims 1-3, for the grate track boundary elements (11, 13). The grate track boundary element (11, 13) according to any one of claims 1 to 3, characterized in that the locking device ( 51 ) includes a plate and a stud for fixing the plate within the terminal connecting element (25). A combustion grate (5) comprising at least two grate tracks (7, 9) and a grate track boundary element (11) according to any one of claims 1-3, positioned between the at least two grate tracks (7, 9). A combustion grate (5) comprising at least one grate track (7) and a grate track boundary element (13) according to any one of claims 1-3, positioned between the at least one grate track (7) and the side wall (3) of the combustion chamber of the combustion equipment. A combustion apparatus for heat-treating waste, comprising one or more combustion grates (5) as described in claim 12. A combustion apparatus for heat-treating waste, comprising one or more combustion grates (5) as described in claim 13.