WO2017081025A1

WO2017081025A1 - Grate bar, grate and combustion system

Info

Publication number: WO2017081025A1
Application number: PCT/EP2016/077011
Authority: WO
Inventors: Dieter Koch
Original assignee: Seko-Patent Gmbh
Priority date: 2015-11-13
Filing date: 2016-11-08
Publication date: 2017-05-18
Also published as: EP3168534B1; EP3168534A1

Abstract

The invention relates to a grate bar (10) comprising a substantially closed surface (18) facing a combustion side, a grate bar rest (14) designed for resting on a grate cover shaft (16), a head part (12) and a plurality of cooling ribs (28) for air cooling, which protrude from the underside of the surface (18). The head part (12) comprises at least one flow channel (30) which is divided downstream into at least one first and second sub-flow channel (32, 34). The first sub-flow channel (32) leads to at least one first outlet opening (36) on the end side (20) of the head part (12), and the second sub-flow channel (34) leads to at least one second outlet opening, at a distance from the end side (20), which is open to the the underside of the surface (18).

Description

Grate, rust and incinerator

The present invention relates to a grate bar, a grate and an incinerator according to the independent claims.

For the combustion of different fuels, e.g. Household waste, industrial waste, wood waste, solid or porous fuels, as well as fuels with high and low ignition, come conventionally

Combustion systems with combustion chambers for use, in which the fuel is applied, for example, to a mechanically operated grate and burned on it. The grate may include one or more grate bars. at

Combustion plants are usually processed combustion material with high and low calorific value, so that in the grate bars used large heat-related problems can occur. Especially in the Rostkopfbereich the

Grate bars may cause this due to excessive thermal

Burn or corrode load.

An object of the present invention is to provide a grate bar, which has a long

Lifespan has. Furthermore, it is the task of a grate for use in an incinerator and a

To provide incinerator with at least one such grate. The object of the invention is achieved by means of a grate bar according to claim 1. Further embodiments are shown in the dependent claims.

Proposed is a grate bar with a substantially closed, facing a combustion side

Surface, a trained for resting on a Rostbelagswelle grate bar support, a head part and a plurality of cooling fins for air cooling, which project from the underside of the surface, wherein the head part comprises at least one flow channel, which

downstream into at least a first and second

Partial flow channel is divided, with the first

Partial flow channel to at least a first

Outlet opening at the front side of the head part leads and the second partial flow channel leads to at least one spaced from the end face second outlet opening, which is open to the underside of the surface. Such a trained grate bar has a significant

extended life, as particularly heat-stressed

Sections of the grate bar a temperature-adapted

Cooling volume to dissipate the heat is facing. In this case, in particular the head part of the grate bar, which is exposed to particularly high temperature influences and is therefore subject to high wear, reliably cooled. The first outlet opening can allow the airflow to escape to the front and / or to the side. The second outlet opening can allow the air flow to emerge upwards and / or to the side. Overall, an example triple cooling of the head part of the grate bar can be achieved. On the one hand, combustion air enters from below the grate bar in the direction of flow, whereby high heat dissipation is made possible by air circulation. For example, a substantial proportion of the air flowing directly from below the grate bar in the flow direction is ejected directly through the at least one second outlet opening in the surface upwards. On the other hand, advantageously, the head part of the grate bar in the area facing the combustion chamber side of the incinerator is cooled by circulating combustion air. Furthermore, the heat input of the grate bar during operation in the combustion system is removed by the plurality of cooling fins. The cooling fins extend from the bottom of the surface of the grate bar down. It can be provided, for example, six mutually parallel cooling fins, the two

Final longitudinal edges of the grate bar can also be designed as cooling fins. The cooling fins are thus formed as cooling channels and provide sufficient cooling surface. This results in a high heat dissipation

guaranteed, which by the aforementioned

circulating flow air is discharged to the outside. The number of cooling fins and / or their dimensions, for example their thickness, can be adaptable and can be matched to the respective combustion purpose. Preferably, the first partial flow channel emerges forward relative to the longitudinal direction of the grate bar and / or extends forwardly from at least one of the sides of the grate bar. For example, as more air is directed to the front, the air supply to the front side and thus the fuming of the here burning

Materials are regulated. In order that the temperature at the front side does not become too high as a result of the fanning in, it is possible, for example. reduces air to the front and more air to be directed upwards.

Preferably, the second partial flow channel enters

Relation to the longitudinal direction of the grate bar upwards

and / or from at least one of the sides of the grate bar directed upwards. So that the temperature at the

Top of the surface of the grate bar by e.g.

Fanning does not become too high, can e.g. decreases air upwards and more air is directed forward.

Preferably, the flow channel is at least

partially arranged between the inner surface of the end face of the head part and a distance therefrom

Section formed a flow air guide element. Here, the flow-air guide element may also be formed as at least one cooling fin, which extends substantially perpendicular to the longitudinal extent of the grate bar. The end face and at least a portion of the flow air guide element can in this case parallel

spaced apart. Within the thus trained flow channel, the flow of air can flow freely and thereby advantageously dissipate heat to the outside.

Preferably, the first exit opening is formed by a gap between a portion of the end face and a front edge portion of the surface. This gap forms a section of the first

Part flow channel. In other words, a first portion of the divided flow air can escape through this gap. The first partial flow channel can be changed in its dimensions, so as to vary the air ejection or volume flow from the first outlet opening at the front end side. Advantageously, this proportion of the flow air cools the combustion chamber facing the front side of the grate bar by heat dissipation to the outside. In this case, the front edge section of the surface may overlap the upper end of the front side, so that the first portion of the flow air emerging from the first partial flow channel can be deflected by 180 °. This deflected portion of the flow air can then sweep downstream as large a surface area of the outer end face and thus dissipate heat.

Of course, different deflection angles are adjustable, which differ from 180 °.

Preferably, the front side and / or the surface is at least partially with a heat-resistant layer which comprises a plurality of ceramic sheets.

Preferably, the heat-resistant layer comprises a

Ceramic material. The heat-resistant layer can

alternatively or additionally slag and / or not

Include flammable components. Here, the

heat resistant layer at least at the top of the

Roststabes be provided. For example, the

heat-resistant layer extend to the second outlet opening. Alternatively, the heat-resistant layer may extend across the second exit aperture to e.g. 50% to 70% of the length of the grate bar extend. Further alternatively, the heat-resistant layer may extend over the entire length of the grate bar. The heat resistant

Layer includes the plurality of ceramic sheets, which

altogether serve as a heat shield and thus prevent excessive heating of the grate bar. Thus, the

Life of the grate bar can be extended.

Preferably, at least portions of the

End face and / or the surface of a plurality of wedge-shaped depressions, within which the

Ceramic tracks are at least partially registered. The wedge-shaped depressions are formed such that they are tapered in the direction of the outside. By the term "wedge-shaped to the outside tapered recess" is meant that the cross section of the recess to

Outside decreases. In other words, that is Edge length of the recess in the material of the grate bar greater than the edge length on the outside thereof. By this configuration, the material of the

Ceramic sheets after curing reliably in the

Wells kept. In the formed wells, other materials may alternatively be fixed, such as e.g. Slag, non-combustible components or refractory concrete. The material of the grate bar and the material of the ceramic sheets usually have different thermal expansion coefficients. The design of the

Recesses in wedge-shaped form prevented despite the entry of great heat and also different

Thermal expansion coefficient between the rod material and ceramic sheet material reliably detaching the

Ceramic tracks or the ceramic layer of the grate bar. The ceramic material is thus reliable in the

Wells and thus provides a lasting

Heat shield.

Preferably, the wedge-shaped depressions on the front side and / or on the surface in relation to

Grate bar aligned vertically and / or horizontally. Thus, the ceramic sheets in a variant at the

Front and / or on the surface in several

run parallel tracks. In a preferred variant, however, the ceramic webs run on the front side and / or on the surface in vertical and horizontal

Tracks. Here, the tracks preferably cross each other perpendicular. Due to the cross-shaped extent of Ceramic tracks are prevented from being levered out during operation. The cured ceramic sheets are in fact in all

Directions positively connected to the material of the grate bar and therefore can not by resting

Material, e.g. on the surface, or by adjacent material, e.g. at the front, to be moved.

This reliably prevents portions of the ceramic layer or even the entire ceramic layer from detaching or detaching from the grate bar. Thus protects the

Ceramic layer the grate bar overall reliable and durable against heat.

Preferably, the grate bar comprises at least one

Deflection element, which is arranged at the first outlet opening, wherein at least one air guide surface of the deflecting element is aligned in such a way to deflect the exiting air flow directed at an angle to the front. Here, the air flow can be deflected such that the air flow at a predetermined distance to

The end face of the head part impinges on the fuel, or the burning fuel charged with air and thus fanned. By appropriate selection of the angle thus the temperature can be adjusted on the front page. In addition, by redirecting the exiting air too much fluidization of material, e.g. Ashes, which lies in front of the front, are avoided.

Preferably, the deflecting element comprises a at the

Outside of the front side arranged first Wedge portion and / or formed on the edge portion of the surface of the second wedge portion. In this case, air guide surfaces of the wedge sections facing each other and form an exit channel therebetween, which is aligned at an angle. Another advantage of

Deflection element is that this

Air turbulence on the front page can produce, which can bring about improved heat dissipation. Likewise, by the first and second wedge portion a

Penetration of foreign matter, e.g. Fuel, ash, slag, etc., are prevented in the first outlet opening, whereby blocking of the first outlet opening can be prevented.

Preferably, an end of the leading edge portion of the surface is a predetermined distance from a

Supporting surface of the grate bar spaced, the distance at least 50%, preferably at least 70%, of the

Total height of the front edge portion is spaced. This can ensure that the front

Outlet or not greatly reduced with externally applied materials, such as kiln, slag, ash, etc., come into contact. Of course, the distance at which the front edge portion of the surface of a bearing surface of the grate bar

spaced apart, depending on the particular embodiment also accept other values, such. at least 80%, at least 90%, etc. Thus, on simple and

reliable way prevents the front Outlet opening is clogged. A clogging of the

front outlet has the undesirable effect that the air circulation is interrupted, which

again has a negative effect on the cooling effect. Thus, the said embodiment allows a long-lasting and reliable cooling of the grate bar and a concomitant extended life of the

Grate bar.

Preferably, the second partial flow channel is at least partially formed between an underside of the surface and a spaced therefrom arranged portion of the flow air guide element. The second

Partial flow channel can be changed in its dimensions, so as to vary the air ejection or volume flow from the second outlet opening at the surface. Another section of the second partial flow channel is formed by the direct connection from below the grate bar via the cooling fins to the second

Outlet. The air ejection or volume flow respectively from the front first outlet opening and the upper second outlet opening of the surface are variable in relation to each other from 0 to 100%. For example, a volume flow of 30% from the first outlet opening and a volume flow of 70% from the second outlet opening of the surface can be set. All settings in the range of 0 to 100% are possible. This setting or variation can be achieved, for example, by appropriate dimensioning of the first and / or second Part flow channels can be realized. It should be noted that by reducing the first outlet opening, an increased volume flow is set via the direct path between the underside of the grate bar and the second outlet opening. Overall, this is one of the

appropriate cooling allows for each application.

Preferably, the second partial flow channel is at least partially between the underside of the grate bar and at least one of the second outlet openings

formed, which is introduced in the longitudinal side of the grate bar. By the air from at least one

Opening on at least one of the longitudinal sides, may, in relation to the grate bar, the escape of air at the front end, i. forward, and / or at the

Surface, i. upwards, the grate bar adjusted or regulated.

Preferably, the flow air guide element is integrally formed with the cooling fins and at least

partially formed as a wear element.

As a result, during the progressive wear of the front head part, for example an operational material detachment on the particularly stressed end face of the grate bar (wear), the flow air guide element arranged behind the end face can simultaneously serve as a wear element. Thus, advantageously, a continued use of the grate bar can be realized. Overall, the life of the grate bar is extended. Preferably, the cooling fins extend in the longitudinal direction of the grate bar and project in relation to the longitudinal direction with variable depth from the underside of the surface, preferably the depth of

Cooling fins from the headboard in the direction of the grate bar support in the longitudinal direction is decreasing. For example, the cooling fins are more in the range of the claimed by particularly high temperatures headboard than in the area over the length of the grate bar opposite grate bar support. This transition can be linear or non-linear. In other words, the depth of the cooling fins over the length of the grate bar may be linear or non-linearly variable. Here, the variable in relation to the longitudinal direction of the grate bar depth of the cooling fins are related to the temperature profile of the grate bar during operation. Thus, the cooling fins are the temperature profile of

Rust bar adapted during operation, which on the one hand a further reliable heat dissipation is realized to extend the life and on the other hand material and weight and thus costs of the grate bar can be saved altogether. It also costs in warehousing and transport are saved. The depth of the cooling fins can decrease from the head part in the direction of the grate bar support in the longitudinal direction. As a result, a greater heat dissipation can be realized in the region of the head part than in the area opposite the length of the grate bar

Grate bar pad. This feature takes into account the fact that the front headboard is exposed to much higher temperatures and thus should be cooled more than the area of the grate bar support located at the opposite end of the grate bar. The spaces between each adjacent cooling fins are as cooling channels

educated. As a result, the cooling surface is increased overall. Further, the heat radiated on the surface of the cooling fins can be easily dissipated by circulating air cooling within the cooling channels. The number and dimensions (e.g., depth) of the cooling channels can be adapted to different calorific values, fuels and grate systems. Furthermore, the cooling channels in

Depending on the purpose of combustion can be adjusted in size and number. As a result, the efficiency of the grate bar can be increased, at the same time sufficient cooling and the resulting extended

Lifespan. By reducing the temperature difference by means of the matched cooling fins, heat induced mechanical stresses in the grate bar are reduced. Thus, the risk of temperature fractures is significantly reduced.

Preferably, the at least one second

Outlet opening maximum up to 20% in relation to

Total length of the surface away from the leading edge. The distance between the second

Of course, the exit opening in relation to the total length of the surface from the leading edge may also have other values as long as the second exit opening is located at a position in the surface at which only fuel is run over during operation. This avoids that the second outlet opening of a grate bar is covered by one or more grate bars of a row of grate bars arranged above and thereby the air ejection from the second

Outlet opening is partially or completely blocked. The grate bar may comprise a material which is metal

contains. The grate bar can be made of a material of a

Metal alloy be formed.

Preferably, the grate bar as Wenderoststab

educated. Such Wenderoststäbe can, as soon as the end of the life of the first head part

(advanced wear), which in operation

is exposed to particularly high temperature influences is reached, turned, or by 180 ° to the

Center axis turned perpendicular to the surface or

be panned. After turning then the former opposite headboard of the grate bar can be used again over a long period of operation. To realize the turning bar, two support surfaces or grate bar supports arranged symmetrically with respect to the center of the grate bar are formed on the underside of the grate bar. Thus, the life of the grate bar can be nearly doubled, thereby realizing high cost savings.

The above object is also achieved by a grate for use in an incinerator, wherein the grate comprises at least one grate bar according to one of claims 1 to 18. Such a rust for use in one Combustion plant offers a large combustion area. It can be arranged with their long sides parallel to each other aligned to a transverse row several grate bars.

Preferably, the grate comprises a plurality of

successively arranged transverse rows of a plurality of grate bars. The transverse rows arranged one behind the other can be arranged overlapped at least in sections. At least one grate bar can overlap with its bearing surface the surface of a subsequent grate bar shingled. For example, a first transverse row of several grate bars is movable

arranged and is at least partially overlapped second transverse row of several grate bars fixed to the first transverse row. By this arrangement it is achieved that the combustion material can be continuously moved or advanced towards the combustion side.

The above object is also solved by a

Combustion plant comprising a grate according to claim 19 or 20. In such an incinerator

Maintenance intervals are extended. Such

Combustion plant thus advantageously has to be shut down less frequently than in currently known incineration plants. Thus, the efficiency of

Incinerator improved. It is expressly stated that the

above variants are arbitrarily combinable. Only those combinations of

Variants are excluded, which would lead to contradictions through the combination. In the following, the present invention will be explained with reference to embodiments shown in the drawings. Showing:

Fig. 1: a plan view of a surface of a

Grate bar,

2a is a side sectional view along a line E-E of the grate bar shown in Fig. 1 in a first embodiment,

FIG. 2b is a sectional view taken along a line C-C of the grate bar shown in FIG. 2a; FIG.

3a shows a schematic side view of the grate bar in the first embodiment,

3b is a view of a rear end of the grate bar in the first embodiment, a view of a front end of the grate bar in the first embodiment,

a sectional view taken along a line A-A of the grate bar shown in Fig. 2a in one

Top view,

FIG. 2 is a side sectional view taken along a line E-E of the grate bar shown in FIG. 1 in a second embodiment; FIG.

a sectional view taken along a line C-C of the grid bar shown in Fig. 5a,

a schematic side view of the grate bar in the second embodiment,

a view of a rear end of the grate bar in the second embodiment,

a view of a front end of the grate bar in the second embodiment,

1 is a side sectional view along a line EE of the grate bar shown in FIG. 1 in a further variant of the second embodiment, FIG. 8a: a partial section of the head part of the grate bar in a first variant of a third embodiment,

Fig. 8b: a partial section of the head part of the grate bar in a second variant of the third

embodiment,

Fig. 8c: a view on the end face of the head part in the second variant of the third embodiment, and

9 shows a schematic side view of several

stacked grate bars to form a grate.

Figure 1 shows a plan view of a grate bar 10. Figure 2a shows a side sectional view of the grate bar 10 shown in Figure 1 taken along a line E-E in a first

Embodiment. The grate bar 10 comprises a arranged at its front end head portion 12. Further, the grate bar 10 comprises a arranged at the opposite end of the grate bar 10 grate bar support 14 for resting on a Rostbelagswelle 16 for supporting the grate bar 10. The grate bar 10 is from above by a planar surface 18 completed. The top of the surface 18 is the Furnace combustion chamber exposed (not shown), while the underside of the surface, for example

is impinged by an air flow unit, not shown, with an upward air flow.

The head part 12 comprises an end face 20, whose

Outside the firebox of the incinerator is exposed. The upper end of the end face 20 is surmounted by a front edge portion 22 of

Surface 18, wherein the front edge portion 22 at least partially follows the contour of the upper end of the end face 20. The end face 20 and the front edge portion 22 of the surface 18 are spaced from each other by a predetermined gap. The front

Edge portion 22 of the surface 18 is bent around the upper end of the end face 20 around substantially 90 ° downwardly aligned.

The downwardly directed distal end of the front edge portion 22 overlaps only with the upper end of the end face 20. This provides the distance between the downwardly bent distal end of the surface 18 and the underside of the end face 20, which hereinafter also referred to as support surface 23 In other words, the distance between the distal end of the leading edge portion 22 of the surface 18 and the support surface 23 in relation to the total height of the grate bar 10 is a predominant proportion As a result, the gap between the end face 22 and the surface 18 as far as possible from the support surface 23 and the underside of the grate bar 10 spaced, which can be avoided that foreign substances enter the gap and can clog it.

The grate bar 10 further includes a Strömungsluft- guide element 24, which within the grate bar 10th

is arranged or hereby integrally formed. The flow air guide element 24 comprises a vertical

Section 24a, which is substantially parallel to

End face 20 is aligned, and a horizontal portion 24 b, which is substantially parallel to

Surface 18 is aligned. All sections 24a, 24b of the flow air guide element 24 are in this case both to

Front side 20 as well as the underside of the surface 18 spaced.

The longitudinal sides of the grate bar 10 are delimited by side surfaces 26 to the outside. The interior of the

Grate bar 10, that is to say the underside thereof streamed by the air flow, is equipped with a multiplicity of cooling ribs 28 which project from the underside of the surface 18, as can best be seen from FIGS. 2b, 3b and 3c. The cooling fins 28 are used for air cooling and extend parallel to each other in the longitudinal direction, as best seen in FIGS. 1 and 4. The

Cooling fins 28 also extend parallel to the side surfaces 26 and together form one enlarged surface, thus a substantial

to provide increased heat radiation area. For example, four cooling fins 28 (exclusively the two side surfaces 26) may be provided.

Of course, the number of cooling fins 28

vary according to the application. The cooling fins 28 are preferably integral with the entire grate bar 10th

educated .

As previously mentioned, the grate bar 10 is flown from below with an air flow. A portion of this air flow flows within cooling channels, which are each formed between the cooling fins 28 as well as between the side surfaces 26 and a respectively spaced apart therefrom cooling fin 28. Thus, the heat radiated from the cooling fins 28 as well as the side surfaces 26 can be easily dissipated by means of the air flow through the cooling channels, whereby the total temperature of the grate bar 10 can be reduced during operation.

In operation, the head portion 12 is in relation to others

Regions of the grate bar 10 exposed to a particularly high temperature. It has therefore been shown in practice that in particular the head part 12 of the grate bar 10 may be exposed to a relatively rapid heat-related wear, this wear can lead to failure of the entire grate bar 10. To this very high heat input in the region of the head part 12 particularly reliable

derive the cooling fins 28 protrude in the region of Head portion 12 maximum from the bottom of the surface 18 before. With increasing distance from the head part 12 in the direction of the opposite grate bar support 14 protrude

Cooling fins 28 continuously reduced from the bottom of the surface 18 before. The decreasing from the head portion 12 to the grate bar support 14 depth of the cooling fins 28 is based on the

Figures 2a and 3a to recognize particularly clearly. In other words, the cooling fins 28 have a

Temperature gradient adapted dimension or depth.

Advantageously, heat-induced

mechanical stresses in the grate bar 10 are reduced by temperature differences across the grate bar 10 away by means of the matched cooling fins 28 are reduced. Thus, the danger is substantially reduced that the

Grate bar 10 is destroyed by temperature break.

Another portion of the stream of air flow flows along a flow channel 30, which between the end face 20 and a vertical portion 24a of the

Flow air guide element 24 is formed. The

In this case, air flowing inside the flow channel 30 carries off the heat radiated from the end face 20. In the upper part of the flow channel 30 of the goes

Flow channel 30 in a first partial flow channel 32 via. The first partial flow channel 32 leads to a

Outlet opening 36 (gap) between the upper end of the end face 20 and the downwardly bent front edge portion 22 of the surface 18th A second partial flow channel 34 leads to at least one introduced in the surface 18 second outlet opening 38. It should be noted that a high proportion of the total volume flow supplied over the second

Partial flow channel 34, i. the direct path from below the grate bar via the cooling fins 28, to the second

Outlet opening 38 can be ejected. The second outlet opening 38 is preferably formed as an outlet slot. A share of the second

Partial flow channel 34 flowing air flow can via a channel between the horizontal portion 24 b and the

Bottom of the surface 18 toward the first

Outlet opening 36 are passed and ejected there. The first and second partial flow channel 32, 34 and the flow direction of the volume flows are indicated schematically by arrows in FIG. In the in the

Figures illustrated embodiment, two second outlet openings 38 are designed as slots. Although not shown, second outlet openings can be laterally

be provided, which at least a portion of the air flow, spaced from the front side, laterally omit. Of course, the number of second outlet openings 38 may vary. The second

Outlet openings 38 are arranged in areas of the surface 18 between the cooling fins 28. The second

Outlet openings 38 can be introduced into the surface 18 in each case in an area to the right and to the left of a respective cooling rib 28 and / or side surface 26. The respectively flowing in the first and second partial flow channel 32,34 portions of the air flow or the volume flow are thus each by the front first

Outlet opening 36 and the upper second outlet opening 38 expelled to the outside and thereby conduct heat to the outside. The through the first outlet opening 36th

expelled portion of the air flow is in the first embodiment, due to the deflection of the

Essentially 180 °, ejected downwards. Of the

ejected proportion of the air flow can flow over significant portions of the outer surface of the end face 20 and thus dissipate the radiated heat thereof. Although not shown, several first

Outlet openings are provided, through which a portion of the air flow in the region of the head part 12 can be ejected laterally.

The first and second partial flow channels 32, 34 are

at least in sections adjustable to variable flow rates or variable air output changeable. Thus, the volume flows of each of the air ejection from the first outlet opening 36 on the end face 20 and the air ejection from the second outlet opening 38 on the surface 18 are advantageously variable.

Of course, in addition or alternatively, the respective volume flows of the air ejection from the first outlet opening 36 and / or the air outlet from the second outlet opening 38, in each case from at least one of the sides of the grate bar 10, be variable. The The setting can be 0 to 100% in relation to the total volume flow supplied. For example, it may be provided that 30% of the total

Volume flow through the front outlet opening 36th

is ejected while 70% thereof is ejected through the upper second outlet opening 38. Due to the variably adjustable volume flows in the range of

Head portion 12 of the grate bar 10 may be a

application-specific efficient cooling thereof can be set.

The volume flow of the portion flowing through the second outlet opening 38 can be achieved, for example, by adjusting or adapting the second outlet opening 38 itself. For this purpose, for example, the extent or the dimension of the second outlet opening 38 can be changed. In one example, the length of the slot of the second exit port 38 may be changed (shortened or extended). Alternatively or additionally, the width can be changed. Although two in FIG. 2b

Outlet openings 38 are indicated in a region of the surface 18 between the second and third and the third and fourth cooling rib 28, the

Outlet openings 38 are alternatively or additionally arranged in a region of the surface 18 between the other cooling fins 28 and outside the side surfaces 26. If the front first outlet opening 36, for example, by changing the variably adjustable exiting air volumes, is greatly narrowed or completely blocked, the portion of the air flow flowing through the flow channel 30 is wholly or partly passed through the channel between the horizontal portion 24 b and the underside of the surface 18 in the direction of the second outlet opening 38.

Another advantage of the variably adjustable air volumes exiting is that this also the respectively expelled air pressure can be regulated. For example, when burning biomass and wood chips, it is desired that the air emanates under the grate with a relatively low air pressure. The reduction of the air pressure at this point can be achieved, for example, by increasing the second outlet openings 38. Thus, the total is the

Dust re-circulation within the combustion chamber of the incinerator reduced. By ejecting the air from at least one of the sides of the grate bar 10, the dust re-agitation can be further reduced in an application-specific manner.

In order to continue to ensure a reliable air ejection from the second outlet opening 38, this second outlet opening 38 is positioned such that it is run over only by fuel. In other words, the outlet opening (s) 38 is or are arranged such that they are not covered by sections of a grate bar 10 arranged above it (eg the support surface of an upper grate bar) and thus blocked. The dimension of the second outlet opening 38 can also advantageously be chosen such that no or only reduced foreign material from above, for example, ashes and light metals, can pass through the second outlet openings 38 and thus through the grate bar 10th

fall. Overall, a fall of

Foreign material can be prevented by a particularly narrow design of the outlet openings 38. By the

Adaptability of the outlet openings 38, a high air resistance of the grate coating can be achieved, which in particular for the combustion of garbage

is advantageous. A levering of the grate bar 10 can be prevented by the grate bar support 14 is adapted to the Rostbelagswelle 16 the shape of this wave.

FIG. 5a shows a grate bar 10 of a second one

5 shows a sectional view taken along a line CC of the grate bar 10 shown in FIG. 5a. FIG. 6a shows a schematic side view of the grate bar 10 in the second embodiment, and FIGS 6b, c show one each

View on a back or a front end of the

Grate bar 10 in the second embodiment. In

different embodiments of the grate bar 10 are awarded over the description of the same components and the same reference numerals. The grate bar 10 in the second embodiment comprises a deflecting element 39, which is arranged at the first outlet opening 36, wherein at least one air guiding surface of the deflecting element 39 is aligned such that the

emerging airflow is deflected at an angle directed forward. Thus, a targeted air deflection is possible. Here, the air flow can be deflected such that the air at a predetermined distance from the end face 20 of the head part 12 to the upstream

Fuel impinges and the burning fuel is supplied with air and thus, for. fanning. By

appropriate selection of the angle can thus be reduced, the temperature at the end 20. In addition, by redirecting the exiting air too much fluidization of the upstream material, e.g. Ash, to be avoided.

The deflecting element 39 comprises a first wedge section 39a arranged on the outside of the end face 20

and / or a second wedge portion 39b formed on the edge portion of the surface 18. Here are

Air guide surfaces of the wedge portions 39a, 39b facing each other and form therebetween an outlet channel, which is aligned at an angle to the front. Another advantage of the deflecting element 39 is that air turbulences can advantageously be produced on the end face 20, which can bring about improved heat dissipation. Further, these air turbulences may have beneficial effects of fuel combustion. Further advantageously, by the first and second wedge portion 39a, 39b penetration of eg fuel, ash and slag in the first outlet opening 36 can be prevented. Thus, blocking of the first

Outlet opening 36 advantageously prevented.

FIG. 7 shows a side sectional view along a line E-E of the grate bar 10 shown in FIG. 1 in a third embodiment. In the illustrated embodiment of the

Grate bar 10 is another flow air guide element 24 'is provided, which is arranged in the direction of the interior of the grate bar 10 behind an upstream flow air guide element 24' '. In the event of wear of the upstream flow air guide element 24 '', this further flow air guide element 24 'then serves as

Wear object. Thus, a continued operation of the grate bar 10 is guaranteed even after wear of the upstream flow air guide element 24 ''. As a result, the life of the grate bar 10 is extended overall, whereby intervals for replacing the grate bar 10th

can be delayed. Overall, thus high cost savings can be realized.

Figure 8a shows a partial section of the head part 12 of the grate bar 10 in a first variant of a third

Embodiment, and Figure 8b shows a partial section of the head portion 12 of the grate bar 10 in a second variant of the third embodiment. At the third

Embodiment of the grate bar 10 is equal to the second embodiment, the downstream flow air guide element 24 ', which is behind the upstream

Flow air guide element 24 '' is arranged so as to serve in the event of wear of the upstream Strömungsluft- guide element 24 '' as a further Verschleissobj ect.

In addition, in the third embodiment, the

Front side 20 and a portion of the surface 18 in

Area of the head part 12 covered with a heat-resistant layer, which is also referred to below as a ceramic layer. The ceramic layer comprises a plurality of refractory sheets 40, which may comprise ceramic. The heat-resistant webs 40 are also referred to below as ceramic webs 40. Overall, the ceramic layer protects the grate bar 10 reliably against heat.

For this purpose, the end face 20 and the section of

Surface 18 provided in the region of the head portion 12 with wedge-shaped depressions 42, within which the

Ceramic tracks 40 are registered. On the end face 20, the wedge-shaped recesses 42 are shown in the transverse direction to the grate bar 10 and horizontally aligned (see Figures 8a, b). On the surface 18, the wedge-shaped recesses 42 are also shown aligned in the transverse direction to the grate bar 10 (see Figure 8b). Thus, the

Ceramic tracks 40 aligned parallel to each other tracks. As shown in FIG. 8 c, in a preferred variant, the ceramic webs can be provided on the front side 20 and on the surface or on the front edge section 22 in FIG

horizontal and vertical tracks. For this purpose, the recesses 42 are entered perpendicular to each other in the material of the grate bar. Once the ceramic material is recessed into the recesses 42 and cured, the ceramic sheets extend perpendicular to each other (not shown). Due to the cross-shaped extent of the ceramic sheets whose Aushebung from the recesses 42 is reliably prevented. In other words, the cured ceramic sheets are in all directions

positively connected to the material of the grate bar. Thus, it is avoided that the ceramic sheets by lying on the surface material and on at the

Front side 20 adjacent material to be moved. In addition, a detachment of the ceramic sheets is also prevented on the heavily stressed front edge portion 22.

Overall, by the cross-shaped arrangement or

Forming the ceramic sheets reliably prevents portions of the ceramic layer from detaching or even detaching the entire ceramic layer from the grate bar. Thus, the ceramic layer protects reliable overall and durable the grate bar against strong heat.

A further advantage of the crosswise arrangement of the ceramic tracks 40 shown in FIG. 8c is that they thus provide an increased area. In other words, As a result, a smaller area of the material of the grate bar 10 is exposed to the intense heat.

For better illustration, recesses 42 with recessed ceramic tracks 40 are shown in FIGS. 8 a, b in the region of the end face 20 or additionally in the region of the surface section of the head part 12. The

Ceramic sheets 40 may alternatively or in addition to the ceramic also include slag, non-combustible components or refractory concrete. As shown in FIG. 8 b, the ceramic sheets 40 may be provided on the surface 18 at least in the region of the head part 12 of the grate bar 10 and in this case extend only as far as the second outlet opening 38. Although not shown, the

Ceramic sheets 40 across the second exit opening 38 along e.g. 50% to 70% of the length of the grate bar 10 extend. Also, the ceramic sheets 40 may extend over the entire length of the grate bar 10. The

Ceramic layer with the respective ceramic tracks 40 serves as a heat shield and protects the grate bar 10 against

excessive heating.

As previously mentioned, the ceramic sheets 40 are inserted within the wedge-shaped recesses 42. Here, the top side of the respective ceramic sheets 40 may be connected to the upper edge of the recesses 42, i. the not removed

Sections of the grate bar, substantially flush

to lock . The wedge-shaped recesses 42 are formed so that they are in the direction of the outside rejuvenate. In other words, the cross-section of the recesses 42 decreases towards the outside, or is the

Edge length of the respective recesses 42 in the material of the grate bar 10 is greater than the edge length at the

Outside of it. Thus, after curing, the ceramic layer 40 is reliably held within the recesses 42. In wells 42, other materials may alternatively be set, such as e.g. Slag, non-combustible components or

refractory concrete.

The coefficient of thermal expansion of the grate bar 10 is higher than that of the ceramic sheets 40. In order nevertheless to prevent detachment of the ceramic sheets 40 from the grate bar 10, while the grate bar 10 is exposed to high temperatures, the recesses 42 are wedge-shaped such that the recesses 42 in the direction taper to the outside, or the cross-section of the recesses 42 decreases towards the outside. Thus, the ceramic sheets 40 remain reliably connected to the grate bar 10, even if its material expands by heat stronger than the ceramic sheets 40 itself. An additional hold is provided by the cross-type arrangement of the ceramic sheets 40 shown in FIG. 8c

given to each other. The ceramic sheets 40 are thus positively connected in all directions with the material of the grate bar 10. The ceramic sheets 40 thus remain

reliable within the recesses 42 and therefore form a durable and reliable heat shield. As shown in Figure 9, a plurality of grate bars 10 are arranged in several rows one above the other and thus form an inclined plane over which the kiln (not shown) runs, or thus serve to transport the kiln via a thus formed overall grate 44. Hier Cross rows of several grate bars 10 partially overlap one another. The single ones

Transverse rows can be displaced against each other, thus allowing a transport of the fuel by a mutual displacement of the overlapping grate bars 10. In one example, a fixed, that is not movable, transverse row of grate bars 10 may be interposed between two movable transverse rows of grate bars 10.

Claims

claims

A grate bar (10) comprising a substantially

closed, a combustion side facing surface

(18), a grate bar support (14) adapted to rest on a grate decking shaft (16), a head portion (12) and a plurality of cooling fins (28) for air cooling projecting from the underside of the surface (18), the head portion (16) 12) comprises at least one flow channel (30), which is subdivided downstream into at least a first and second partial flow channel (32,34), wherein the first partial flow channel (32) to at least a first

Outlet opening (36) on the end face (20) of the head part

(12) and the second partial flow channel (34) leads to at least one of the end face (20) spaced second outlet opening (38) which is open to the underside of the surface (18).

2. grate bar (10) according to claim 1, wherein the first

Partial flow channel (32) in relation to the longitudinal direction of the grate bar (10) towards the front and / or from at least one of the sides of the grate bar (10) directed forward

exit .

3. grate bar (10) according to claim 1 or 2, wherein the second partial flow channel (34) in relation to the longitudinal direction of the grate bar (10) upwardly and / or from at least one of the sides of the grate bar (10) emerges upwards.

4. grate bar (10) according to any one of the preceding claims, wherein the flow channel (30) at least partially formed between the inner surface of the end face (20) of the head part (12) and a spaced therefrom arranged portion (24a) of a flow air guide element (24) is.

5. grate bar (10) according to any one of the preceding claims, wherein the first outlet opening (36) through a gap between a portion of the end face (20) and a front edge portion (22) of the surface (18) is formed.

6. grate bar (10) according to any one of the preceding claims, wherein the end face (20) and / or the surface (18) at least partially with a heat-resistant

Layer is covered, which comprises a plurality of ceramic sheets (40).

7. grate bar (10) according to claim 6, wherein the

heat-resistant layer comprises a ceramic material.

8. grate bar (10) according to claim 6 or 7, wherein at least portions of the end face (20) and / or the surface (18) has a plurality of wedge-shaped depressions (42). within which the ceramic sheets (40)

at least partially registered.

9. grate bar (10) according to claim 8, wherein the wedge-shaped depressions (42) on the end face (20) and / or on the surface (18) in relation to the grate bar (10) vertically and / or horizontally aligned.

10. grate bar (10) according to any one of the preceding claims, further comprising at least one deflecting element (39) which is arranged at the first outlet opening (36), wherein at least one air guide surface of the deflecting element (39) is aligned to the exiting air flow in to deflect at an angle forward.

11. grate bar (10) according to claim 10, wherein the

Deflecting element (39) has a first wedge portion (39a) arranged on the outside of the end face (20) and / or one on the edge portion (22) of the surface (18).

formed second wedge portion (39b).

12. grate bar (10) according to any one of claims 5 to 11, wherein an end of the front edge portion (22) of the

Surface (18) is spaced by a predetermined distance from a support surface (23) of the grate bar (10), wherein the distance is at least 50%, preferably at least 70%, spaced from the total height of the front edge portion.

13. grate bar (10) according to any one of the preceding claims, wherein the second partial flow channel (34) at least

is formed in sections between an underside of the surface (18) and a spaced therefrom arranged portion (24b) of the flow air-guiding element (24).

14. grate bar (10) according to any one of the preceding claims, wherein the second partial flow channel (34) at least

is formed in sections between the underside of the grate bar (10) and at least one of the second outlet openings (38) which is introduced in the longitudinal side of the grate bar (10).

15. grate bar (10) according to any one of claims 4 to 14, wherein the flow air guide element (24) integral with the

Cooling ribs (28) and at least in sections as

Wear element is formed.

16. grate bar (10) according to any one of the preceding claims, wherein the cooling fins (28) in the longitudinal direction of the

Roststabes (10) extend and in relation to

Protruding longitudinal direction with variable depth from the underside of the surface (18), wherein preferably the depth of the cooling fins (28) from the head part (12) in the direction of

Roststabauflage (14) is decreasing in the longitudinal direction.

17. grate bar (10) according to any one of the preceding claims, wherein the at least one second outlet opening (38) is arranged a maximum of 20% in relation to the total length of the surface of the front edge.

18. grate bar (10) according to any one of the preceding claims, designed as Wenderoststab.

19. grate (44) for use in an incinerator, comprising at least one grate bar (10) according to any one of claims 1 to 18.

20. grate (44) according to claim 19, comprising a plurality of successively arranged transverse rows of a plurality of grate bars (10).

21. An incinerator comprising a grate (44) according to claim 19 or 20.