EP3931488B1 - Combustion chamber for a hot gas generator of an asphalt production plant with air baffles and method for securing the air baffles - Google Patents

Description

TECHNICAL AREA

The present invention relates to a combustion chamber for a hot gas generator of an asphalt production plant, a hot gas generator comprising the combustion chamber, a plant for the production of asphalt comprising the hot gas generator, a use of the plant for drying and heating granular mineral and/or recycled asphalt material for asphalt production, a method for fastening air baffles in a base body of a combustion chamber for a hot gas generator and a method for connecting air baffles following one another in the longitudinal direction of the combustion chamber in a base body of a combustion chamber for a hot gas generator according to the preambles of the independent claims.

STATE OF THE ART

In systems for drying and heating granular mineral and/or recycling asphalt material for asphalt production, drum dryers with rotating drying drums are used, in which a material curtain is formed from the granular material, which is permeated by a hot gas stream. The material to be dried and heated passes through the drying drum in the same direction as the hot gas flow (cocurrent drum dryer) or in the opposite direction to the hot gas flow (countercurrent drum dryer).

The hot gas flow is provided by a hot gas generator, which is usually fired with fossil fuels such as natural gas, heating oil or coal dust or, for example, also with wood dust, which has a combustion chamber and a burner includes. The combustion chamber in turn includes a fixed base body lined with air baffles that form the radial boundaries of the combustion chamber of the combustion chamber. In normal operation, secondary air is routed between the inside of the base body and the air baffles, which cools the air baffles and is introduced into the combustion chamber at various points through defined openings in order to obtain a hot air flow that is as homogeneous as possible at a specific temperature at the outlet end of the combustion chamber.

In the combustion chambers of this type known today, the air baffles are held axially displaceably on the inside of the base body with retaining plates welded onto radial webs, and the air baffles that follow one another in the longitudinal direction of the combustion chamber are each welded directly to one another or are firmly connected to one another via welded-on connecting profile pieces.

After prolonged operation of the combustion chamber, it may be necessary to replace individual air baffles. Over time, material can also build up in the secondary air area between the inside of the base body and the air baffles, which can impair the air flow and thus the operation and make regular checking/cleaning of this area necessary. However, replacing individual air baffles and inspecting and/or cleaning the secondary air area in today's combustors is very time consuming and labor intensive because it is not possible to easily and safely remove and then reinstall individual air baffles.

The DE202008012971U1 discloses a combustion chamber for a hot gas generator with the features of the preamble of the first claim.

The U.S. 5,363,642 discloses a method for connecting air baffles that follow one another in the longitudinal direction of the combustion chamber in a base body of a combustion chamber.

PRESENTATION OF THE INVENTION

It is therefore the task of technical to provide solutions that meet the aforesaid Do not have the disadvantages of the prior art or at least partially avoid them.

This object is solved by the subject matter of the independent patent claims.

According to these, a first aspect of the invention relates to a combustion chamber for a hot gas generator of an asphalt production plant. The combustion chamber comprises a drum-like base body with a burner end and a hot gas outlet end. Viewed in the circumferential direction of the combustion chamber, the base body is lined on its inside with several successive air baffles for secondary air, the outsides of which face the inside of the base body and the insides of which form the boundaries of the combustion chamber of the combustion chamber.

In combustion chambers of this type, the secondary air used is mostly hot gas or process air from associated processes, e.g. raw gas from a black material drum or chimney air.

The air baffles can each extend in one piece over the entire length of the combustion chamber, viewed in the longitudinal direction of the combustion chamber, or there can be a plurality of air baffles following one another in the longitudinal direction of the combustion chamber, which is preferred.

At least part of the air baffle plates is held in the base body by means of latch-bar arrangements. This is achieved in that fastening tabs protruding radially beyond the inner sides of the air baffles into the combustion chamber are interspersed with fastening bars, which create a form fit in the radial direction pointing towards the center of the combustion chamber between the fastening tabs and the inner sides of the air baffles.

The invention makes it possible to remove individual air baffles from the combustion chamber interior without destroying components and then reinstall them, be it to replace them or to install them again, with little expenditure of time, material and work Check and/or clean the secondary air area.

Retaining plates are preferably arranged between the fastening bars and the inner sides of the air baffle plates, through which the fastening lugs pass. The use of retaining plates results in the advantage that the surface generating the radial form fit with the inside of the respective air baffle can be designed independently of the fastening bar and can thus be optimized for protection against wear.

In a first preferred variant, these holding plates preferably rest without play on the inner sides of the respective air baffle plates, while on their other side they border on the respective fastening bars. In this way, a substantially vibration-free attachment of the air baffles can be achieved.

In a second preferred variant, there are stop surfaces on the inside of the base body, against which the air baffles hit or can hit, pointing outwards in the radial direction, and the retaining plates have such a radial distance from these stop surfaces that the air baffles are located between these stop surfaces and can move the holding plates radially by a certain amount of play. This amount of play is preferably at least 3 mm, in particular at least 5 mm. With this amount of play it can be achieved that during manufacture of the combustion chamber the air baffle plates can be easily installed by axially pushing them in from the hot gas outlet end of the combustion chamber. This also makes it possible to prevent or at least significantly reduce stresses in the event of manufacturing inaccuracies and thermal expansion.

Advantageously, the fastening tabs are located between opposing delimitations of the air baffle plates running in the longitudinal direction of the combustion chamber Combustion chamber inside, the respective fastening bars and / or retaining plates overlap these limitations to form the radial form fit. In this way, free axial displaceability of the air baffle plates can be ensured in a simple and reliable manner.

It is preferred that the fastening tabs arranged between the boundaries of the air baffle plates running in the longitudinal direction of the combustion chamber are interspersed with the fastening bars in the circumferential direction of the combustion chamber. In this way, the tabs can be made very flat in the circumferential direction of the combustion chamber and the distance between the boundaries of the air baffle plates can be chosen to be correspondingly very small.

In a preferred embodiment, the base body of the combustion chamber is lined on its inside with a plurality of successive air baffles both in the circumferential direction of the combustion chamber and in the longitudinal direction of the combustion chamber. The air baffles therefore do not extend in one piece over the entire length of the combustion chamber, viewed in the longitudinal direction of the combustion chamber, but rather several air baffles follow one another in the longitudinal direction of the combustion chamber. This has the advantage that the installation/dismantling of the air baffle plates is simplified and only certain areas can be removed in a targeted manner for replacement or control purposes.

It is further preferred in this embodiment that the air baffles following one another in the longitudinal direction of the combustion chamber are connected to one another so that they expand together during heating and cooling and also contract together again without significant gaps occurring between them. This is advantageously done by means of lug-bar arrangements such that connecting lugs are formed on the opposite delimitations of the successive air baffle plates in the longitudinal direction of the combustion chamber, which project radially into the combustion chamber and enforce a common retaining plate, which creates a form fit in the longitudinal direction of the combustion chamber between the connecting straps. The free ends of the tabs, which emerge from the side of the retaining plate facing the combustion chamber, are penetrated by a connecting bar which secures the retaining plate.

This makes it possible to disconnect and then restore the connection between the air baffles from the combustion chamber interior without destroying components with little expenditure of time, material and work, be it to replace individual air baffles or to check and/or clean the secondary air area to perform.

In a first preferred variant, the connecting lugs, which pass through a common retaining plate, lie on top of one another, as seen in the direction in which the connecting bar is pushed through.

In a second preferred variant, the connecting lugs, which pass through a common retaining plate, lie next to one another as seen in the direction of the connecting bar.

The common retaining plate can be secured with exactly one connecting bar, which passes through each of the connecting straps penetrating the retaining plate, or with several connecting bars, which each pass through each of the connecting straps penetrating the holding plate, or only some of them. Depending on the installation situation, one or the other variant may be more preferable.

If the connecting lugs, which pass through a common retaining plate, are next to one another as seen in the direction of the connecting bar, it is provided, for example, that they together form a passage opening for a connecting bar. In this way, the desired connection can also be produced with such arrangements of the connecting straps with a single connecting bar.

The connecting tabs are advantageously penetrated by the connecting bars in the longitudinal direction of the combustion chamber or in the circumferential direction of the combustion chamber. Depending on the installation situation, one or the other variant may be more preferable.

The fastening bars and/or connecting bars are preferably designed in such a way that they strike at least one of the fastening straps or connecting straps with a stop face in a form-fitting manner in the direction of penetration. In this way, assembly is made easier and a precisely defined installation position can be ensured. In addition, any securing of the bolts is only necessary at one end of the bolts as a result of this configuration.

Such a securing of the fastening bolts and/or connecting bolts is advantageously carried out with a material application after the assembly of the bolt exclusively on its surface by welding, in particular by means of one or by means of several welding points, which positively secure the bolt against removal from the intended position. Such a securing method has the advantage over welding with the tabs and/or retaining plates that the material applied to remove the bolt can be simply ground away with a grinding machine and without material removal on other components and the bolt can then be used again.

The air baffle plates preferably have a profile running in the longitudinal direction of the combustion chamber, so that on their outsides they form flow channels for the secondary air that extend in the longitudinal direction of the combustion chamber.

Advantageously, at least some of the air baffles that follow one another, viewed in the longitudinal direction of the combustion chamber, are designed in such a way, for example by means of a stepped profile, that their facing one another Limitations to the end of the hot air outlet pointing out outlet openings form for secondary air from the respective flow channel extending behind it.

The air baffles that follow one another as seen in the longitudinal direction of the combustion chamber, the boundaries of which face one another form the air outlet openings pointing towards the hot air outlet end, are preferably connected to one another by means of latch-bar arrangements in such a way that at the opposite boundaries of the air baffles in the longitudinal direction of the combustion chamber each connection tabs are formed, which protrude into the combustion chamber. These connecting shackles each pass through a common holding plate, which creates a form fit in the longitudinal direction of the combustion chamber between the connecting shackles passing through it and is each secured by means of a connecting bar which passes through the connecting shackles on the side of the holding plate facing the combustion chamber. This type of connection of the air baffles that follow one another in the longitudinal direction of the combustion chamber in the edge regions of the opposite boundaries of the same means that the central region of the boundaries remains free and offers a great deal of design freedom for the formation of the air outlet openings for secondary air.

It is preferred that the connecting lugs, which each pass through the common retaining plate, lie next to each other as seen in the direction of penetration of the connecting bar and together form a passage opening for a single common connecting bar which passes through the connecting lugs in the circumferential direction of the combustion chamber. Realizing the connection of the air baffles in this way requires particularly little space in the circumferential direction of the combustion chamber and therefore offers maximum design freedom for the formation of the air outlet openings.

Furthermore, it is preferred that at least a part of the combustor longitudinal direction on top of each other following air baffles is profiled in such a way that their mutually facing boundaries adjoin each other essentially steplessly. Advantageously, at least some of these air baffles have air outlet openings pointing toward the combustion chamber for secondary air from a flow channel extending behind them.

These air baffles, which have air outlet openings pointing towards the combustion chamber, are preferably arranged between the hot gas outlet end and the air outlet openings pointing towards the hot air outlet end, viewed in the longitudinal direction of the combustion chamber. It has been shown that a particularly uniform temperature of the hot gas stream exiting the combustion chamber can be achieved in this way.

The air baffles following one another seen in the longitudinal direction of the combustion chamber, which are profiled in such a way that their mutually facing boundaries adjoin one another in an essentially stepless manner, are preferably connected to one another by means of latch-bar arrangements. The connection is designed in such a way that connecting lugs are formed in the central areas on the opposite delimitations of the air baffle plates in the longitudinal direction of the combustion chamber, which protrude into the combustion chamber. These connecting lugs each pass through a common retaining plate, which creates a form fit in the longitudinal direction of the combustion chamber between the respective connecting lugs. The retaining plate is secured by means of a connecting bar, which passes through the connecting lugs on the side of the retaining plate facing the combustion chamber.

The connecting tabs, which each pass through the common retaining plate, are preferably located one above the other as seen in the direction of penetration of the connecting bar and are passed through by a common connecting bar in the longitudinal direction of the combustion chamber. This type of connection of the air baffles that follow one another in the longitudinal direction of the combustion chamber is special easy to manufacture and is preferably realized in the middle of the opposite borders of the same. This results in the advantage that a single tongue-and-bar connection is sufficient for connecting two air baffles that follow one another in the longitudinal direction of the combustion chamber.

A second aspect of the invention relates to a hot gas generator for an asphalt production plant, which has a combustion chamber according to the first aspect of the invention and a burner for generating a hot gas flow through the combustion chamber.

A third aspect of the invention relates to a plant for the production of asphalt, comprising a hot gas generator according to the second aspect of the invention and a drum dryer, preferably a countercurrent drum dryer, which is or can be charged with hot gas by the hot gas generator.

A fourth aspect of the invention relates to the use of the plant according to the third aspect of the invention for drying and heating granular mineral and/or recycled asphalt material in asphalt production.

A fifth aspect of the invention relates to a method for fastening air baffles in a base body of a combustion chamber for a hot gas generator.

The starting point here is a drum-like base body of a combustion chamber for a hot gas generator, in which fastening tabs protruding radially inward are arranged for fastening air baffles.

Air supply plates are arranged in this base body in such a way that when the combustion chamber is finished as intended, they form the radial boundaries of the combustion chamber of the combustion chamber, with the fastening lugs being arranged between opposing boundaries of the air baffles and/or passing through the air baffles, and with the fastening lugs protrude with their free ends radially over the air baffles into the combustion chamber.

The free ends of the fastening straps protruding into the combustion chamber are interspersed with fastening bars in such a way that the fastening bars create a form fit in the radial direction between the fastening straps and the air baffle plates. For this purpose, the free ends of the fastening tabs have passage openings into which the fastening bars are pushed.

The invention makes it possible to remove individual air baffles from the interior of the combustion chamber without destroying components and then reinstall them with little expenditure of time, material and work, whether to replace them or to check and/or clean the Carry out secondary air area.

Advantageously, the air baffles are arranged in the base body in such a way that the fastening tabs protrude into the combustion chamber between opposing boundaries of the air baffles running in the longitudinal direction of the combustion chamber, with the respective fastening bars and/or any existing retaining plates overlapping these boundaries to form the radial form fit. In this way, free axial displaceability of the air baffle plates can be ensured in a simple and reliable manner.

It is preferred that the fastening tabs arranged between the boundaries of the air baffle plates running in the longitudinal direction of the combustion chamber are interspersed with the fastening bars in the circumferential direction of the combustion chamber. In this way, the tabs can be made very flat in the circumferential direction of the combustion chamber and the distance between the boundaries of the air baffle plates can be chosen to be correspondingly very small.

Preferably, between the mounting bars and the insides of the air baffles respectively Arranged retaining plates, which are penetrated by the fastening tabs. The use of retaining plates results in the advantage that the surface generating the radial form fit with the inside of the respective air baffle can be designed independently of the fastening bar and can thus be optimized for protection against wear.

In a first preferred variant, the retaining plates are arranged in such a way that they preferably rest without play on the insides of the respective air baffle plates, while on their other side they adjoin the respective fastening bars. In this way, a substantially vibration-free attachment of the air baffles can be achieved.

In a second preferred variant, stop surfaces are present on the inside of the base body, against which the air baffle plates, pointing outwards in the radial direction, strike or can strike. The holding plates are arranged at such a radial distance from these abutment surfaces that the air baffles can move radially by a certain amount of play between these abutment surfaces and the holding plates. This amount of play is preferably at least 3 mm, in particular at least 5 mm. With this amount of play it can be achieved that during manufacture of the combustion chamber the air baffle plates can be easily installed by axially pushing them in from the hot gas outlet end of the combustion chamber. This also makes it possible to prevent or at least significantly reduce stresses in the event of manufacturing inaccuracies and thermal expansion.

A sixth aspect of the invention relates to a method for connecting air baffles that follow one another in the longitudinal direction of the combustion chamber in a base body of a combustion chamber for a hot gas generator.

In this case, air baffle plates are provided, which have connecting lugs that extend from the end to form a combustion chamber delimitation of the combustion chamber protrude from the intended surface of the respective air baffle.

These air baffles are arranged in a base body of a combustion chamber for a hot gas generator in such a way that the air baffles form the radial boundaries of the combustion space of the combustion chamber when the combustion chamber is finished as intended. In this case, the end-side connecting tabs of air baffles following one another in the longitudinal direction of the combustion chamber are opposite and/or adjoin one another.

A retaining plate with a through-opening is arranged on the respective opposite and/or adjoining connecting lugs in such a way that the connecting lugs pass through the through-opening of the retaining plate and protrude with their free ends beyond the side of the retaining plate facing the combustion chamber into the combustion chamber. The retaining plates each produce a form fit in the longitudinal direction of the combustion chamber between the connecting straps.

The holding plates are each secured by means of a connecting bar which passes through at least one of the connecting lugs on the side of the holding plate facing the combustion chamber.

The invention makes it possible to remove individual air baffles from the interior of the combustion chamber without destroying components and then reinstall them with little expenditure of time, material and work, whether to replace them or to check and/or clean the Carry out secondary air area.

In the method according to the fifth and sixth aspect of the invention, the fastening and/or connecting bars are preferably positively secured against removal from the as intended position secured. Such a securing method has the advantage over welding with the tabs and/or retaining plates that the material applied to remove the bolt can be simply ground away with a grinding machine and without destroying or impairing other components and the bolt can then also be used again.

BRIEF DESCRIPTION OF THE DRAWINGS

• Fig. 1 eine perspektivische Ansicht eines Längsschnittes durch einen erfindungsgemässen Aufbau eines Heissgaserzeugers und eines Trommeltrockners einer Asphaltproduktionsanlage;
• Fig. 2 eine perspektivische Ansicht eines Längsschnittes durch die erfindungsgemässe Brennkammer des Heissgaserzeugers der Asphaltproduktionsanlage aus Fig. 1;
• Fig. 3 das Detail X aus Fig. 2;
• Fig. 4 das Detail Y aus Fig. 2;
• Fig. 5 eine vergrösserte Ansicht eines Teils der Darstellung aus Fig. 3;
• Fig. 6 eine vergrösserte Ansicht eines Teils der Darstellung aus Fig. 4;
• Fig. 7 einen Schnitt entlang der Linie C-C in Fig. 6;
• Fig. 8 einen Schnitt entlang der Linie A-A in Fig. 5;
• Fig. 9 einen Schnitt entlang der Linie B-B in Fig. 6;
• Fig. 10a eine perspektivische Ansicht der in den Figuren 3-6 mit der Bezugsziffer 9a bezeichneten Lasche-Riegel-Anordnung;
• Fig. 10b eine perspektivische Explosionsdarstellung der Lasche-Riegel-Anordnung aus Fig. 10a;
• Fig. 11a eine perspektivische Ansicht der in den Figuren 3 und 5 mit der Bezugsziffer 9b bezeichneten Lasche-Riegel-Anordnung;
• Fig. 11b eine perspektivische Explosionsdarstellung der Lasche-Riegel-Anordnung aus Fig. 11a;
• Fig. 12a eine perspektivische Ansicht der in den Figuren 4 und 6 mit der Bezugsziffer 9c bezeichneten Lasche-Riegel-Anordnung;
• Fig. 12b eine perspektivische Explosionsdarstellung der Lasche-Riegel-Anordnung aus Fig. 12a;

Further configurations, advantages and applications of the invention result from the dependent claims and from the following description based on the figures. show:

• 1 a perspective view of a longitudinal section through an inventive structure of a hot gas generator and a drum dryer of an asphalt production plant;
• 2 a perspective view of a longitudinal section through the inventive combustion chamber of the hot gas generator of the asphalt production plant 1 ;
• 3 the detail X off 2 ;
• 4 the detail Y off 2 ;
• figure 5 an enlarged view of part of the illustration 3 ;
• 6 an enlarged view of part of the illustration 4 ;
• 7 a cut along the line CC in 6 ;
• 8 a cut along the line AA in figure 5 ;
• 9 a cut along line BB in 6 ;
• Figure 10a a perspective view of in the Figures 3-6 tab and bar assembly indicated by reference numeral 9a;
• Figure 10b Figure 12 shows an exploded perspective view of the tab and latch assembly Figure 10a ;
• Figure 11a a perspective view of in the Figures 3 and 5 tab and bar assembly indicated by reference numeral 9b;
• Figure 11b Figure 12 shows an exploded perspective view of the tab and latch assembly Figure 11a ;
• 12a a perspective view of in the figures 4 and 6 tab and bar assembly indicated by reference numeral 9c;
• Figure 12b Figure 12 shows an exploded perspective view of the tab and latch assembly 12a ;

WAYS TO CARRY OUT THE INVENTION

1 shows a longitudinal section through the hot gas generator and the drum dryer of an asphalt production plant 1 according to the invention in a perspective view obliquely from above.

As can be seen, the system 1 comprises a hot gas generator 2 according to the invention and a countercurrent drum dryer 3 for drying and heating granular mineral and/or recycled asphalt material for asphalt production, the internal structure of which is not shown in detail.

How out 2 can be seen, which is an enlarged view of the longitudinal section through the inventive combustion chamber 4 of the hot gas generator 2 of the asphalt production plant 1 1 shows from a different perspective, the combustion chamber 4 comprises a drum-like base body 6 with a burner end A and a hot gas outlet end B. The base body 6 is seen on its inside both in the circumferential direction of the combustion chamber and in the longitudinal direction S of the combustion chamber, with a plurality of successive air baffles 7 (Only some provided with reference numbers) lined, the outside of the inside of the base body 6 facing are and the insides of which form the boundaries of the combustion chamber 8 of the combustion chamber 4 .

The air baffles 7 have a profile running in the longitudinal direction S of the combustion chamber, as a result of which they form flow channels for secondary air that extend in the longitudinal direction S of the combustion chamber on their outer sides.

As in conjunction with the Figures 3 and 4 it is recognizable which the details X and Y consist of 2 show, a part of the air baffle plates 7, namely the air baffle plates 7, which form the fourth to sixth circumferential row of air baffle plates 7 seen downstream from the burner end A, is held in the base body 6 by means of latch-bar arrangements 9a.

As in further synopsis with the figures 5 and 6 , which enlarged views of portions of the representations from the Figures 3 and 4 show with 7 , showing a section along the line CC in 6 shows as well as with the Figures 10a and 10b , which show a perspective view of one of these lug-bar arrangements 9a and a perspective exploded view of the same, these lug-bar arrangements 9a are implemented in such a way that fastening lugs 10 projecting radially beyond the inner sides of the air baffles 7 into the combustion chamber 8 are penetrated by fastening bars 11 are, which produce a positive fit in the radial direction between the fastening tabs 10 and the insides of the air baffles 7.

In this case, retaining plates 12 are arranged between the fastening bars 11 and the insides of the air baffles 7 , through which the fastening lugs 10 pass.

As in particular in 7 can be seen, the inside of the base body 6 forms abutment surfaces 22 against which the air baffle plates 7 abut or can abut in the radial direction outwards, and the holding plates 12 have such a distance a have to these stop surfaces 22 that the air baffles 7 can move between these stop surfaces 22 and the retaining plates 12 radially by the amount of play d. This play dimension d is about 5 mm in the present case.

As can also be seen, the fastening lugs 10 protrude into the combustion chamber 8 between opposite delimitations 13 of the air baffle plates 7 running in the longitudinal direction S of the combustion chamber, and the fastening bars 11 and retaining plates 12 overlap these delimitations 13. The fastening bars 11 thereby penetrate the fastening lugs 10 in the circumferential direction of the combustion chamber.

As if from a synopsis of Figures 2, 3 and 5 As can be seen, some of the air baffles 7 that follow one another when viewed in the longitudinal direction S of the combustion chamber, namely the air baffles 7 which form the second to fourth circumferential rows of air baffles 7 seen downstream from the burner end A, are profiled in such a way that their mutually facing boundaries 14 face the hot air outlet end B form pointing air outlet openings 15 for secondary air from the flow channels extending behind it.

As can also be seen, the air baffle plates 7 forming an air outlet opening 15 are connected to one another by means of two latch-bar arrangements 9b, so that they can only move axially together in the longitudinal direction S of the combustion chamber in the event of thermal expansion or contraction.

As in synopsis with 8 , showing a radial section along the line AA in figure 5 shows, and with the Figures 11a and 11b , which shows a perspective view of one of these tab-bar assemblies 9b and a perspective exploded view of the same, these tab-bar assemblies 9b are each realized in that at the opposite boundaries in the longitudinal direction S of the combustion chamber 14 of the successive air baffles 7 in the edge regions connecting lugs 16a, 16b are formed, which protrude into the combustion chamber 8 and pass through a common retaining plate 17 which creates a form fit in the longitudinal direction S of the combustion chamber between the connecting lugs 16a, 16b. The holding plate 17 is secured by means of a connecting bar 18 which passes through a through-opening formed jointly by the two connecting lugs 16a, 16b on the side of the holding plate 17 which faces the combustion chamber 8 . As can be seen, the connecting lugs 16a, 16b lie next to each other as seen in the direction of penetration of the connecting bar 18 and each form one half of the through-opening for the connecting bar 18, which passes through the through-opening formed by the connecting lugs 16a, 16b in the circumferential direction of the combustion chamber.

As if from a synopsis of Figures 2, 4 and 6 shows, some of the air baffles 7 that follow one another when viewed in the longitudinal direction S of the combustion chamber, namely the air baffles 7 which form the first and second as well as the fourth to eighth circumferential rows of air baffles 7 seen downstream from the burner end A, are profiled in such a way that their mutually facing Boundaries 14 essentially steplessly adjoin each other. The air baffles 7, which form the fifth and sixth circumferential row of air baffles 7 downstream of the burner end A, have air outlet openings 19 (only some provided with reference numbers) pointing towards the combustion chamber 8 for secondary air from the flow channel extending behind them.

As can also be seen, the air baffles 7 that follow one another as seen in the longitudinal direction S of the combustion chamber, which form the fourth to sixth circumferential row of air baffles 7 seen downstream from the burner end A, are each connected to one another by means of exactly one latch-bar arrangement 9c, so that they only move axially during thermal expansion or contraction can move together in the longitudinal direction S of the combustion chamber.

As in synopsis with 9 , showing a section along the line BB in 6 shows, and with the Figures 12a and 12b , which shows a perspective view of one of these latch-bar arrangements 9c and a perspective exploded view of the same, this latch-bar arrangement 9c is realized in that at the opposite boundaries 14 of the successive air baffles in the longitudinal direction S of the combustion chamber 7 in the middle of these boundaries 14 connecting lugs 21a, 21b are formed, which protrude into the combustion chamber 8 and pass through a common retaining plate 17, which creates a form fit in the longitudinal direction S of the combustion chamber between the connecting lugs 21a, 21b. The holding plate 17 is secured by means of a connecting bolt 18 which passes through both connecting lugs 21a, 21b.

As can be seen, the connecting tabs 21a, 21b lie one above the other as seen in the direction of penetration of the connecting bar 18 and are penetrated by the connecting bar 18 in the longitudinal direction S of the combustion chamber.

All fastening and connecting bolts 11, 18 are stepped, so that they strike positively in the direction of penetration with stop surfaces 23 formed by the step on fastening lug 10, on connecting lug 21a or on the two connecting lugs 16a, 16b.

In addition, all fastening and connecting bars 11, 18 are positively secured against removal by a weld point 20 attached to their surface on the combustion chamber side.

While preferred embodiments of the invention are described in the present application, it is to be clearly understood that the invention is not limited to these and otherwise within within the scope of the claims that follow.

Claims (36)

1. Combustion chamber (4) for a hot gas generator (2) of an asphalt production plant (1), comprising a drum-like base body (6) with a burner end (A) and a hot gas outlet end (B), which is lined with a plurality of successive air baffles (7) on its inside, viewed in the circumferential direction of the combustion chamber, the outsides of which face the inside of the base body (6) and the insides of which form the boundaries of the combustion space (8) of the combustion chamber (4),
   characterised in that
   at least a portion of the air baffles (7) is held in the base body (6) by means of tab-bar arrangements (9a) in such a way that fastening tabs (10) extending radially over the inner sides of the air baffles (7) into the combustion space (8) are passed through by fastening bars (11), which show a form fit in the radial direction to the centre of the combustion chamber between the fastening tabs (10) and the air baffles (7).
2. Combustion chamber (4) according to claim 1, wherein retaining plates (12), through which the fastening tabs (10) pass, are arranged between the fastening bars (11) and the insides of the air baffles (7) .
3. Combustion chamber (4) according to claim 2, wherein the retaining plates (12) rest on the insides of the air baffles (7).
4. Combustion chamber (4) according to one of claims 2 to 3, wherein on the inside of the base body (6) there are stop surfaces (22) against which the air baffles (7) pointing outwards in the radial direction strike or can strike, and wherein the retaining plates (12) have such a distance (a) to these stop surfaces (22) that the air baffles (7) can move radially between these stop surfaces (22) and the retaining plates (12) by a certain amount of clearance (d), and in particular, wherein the clearance (d) is at least 3 mm, in particular at least 5 mm.
5. Combustion chamber (4) according to one of the preceding claims, wherein at least a portion of the fastening tabs (10) extend into the combustion space (8) between opposite boundaries (13) of the air baffles (7) running in the longitudinal direction (S) of the combustion chamber, and the respective fastening bars (11) and/or retaining plates (12) overlap these boundaries (13).
6. Combustion chamber (4) according to claim 5, wherein the fastening tabs (10) arranged between the boundaries (13) of the air baffles (7) running in the longitudinal direction (S) of the combustion chamber are passed through by the fastening bars (11) in the circumferential direction of the combustion chamber.
7. Combustion chamber (4) according to one of the preceding claims, wherein the base body (6) of the combustion chamber (4) is lined on its inside with a plurality of successive air baffles (7) both in the circumferential direction of the combustion chamber and in the longitudinal direction (S) of the combustion chamber.
8. Combustion chamber (4) according to claim 7, wherein at least a portion of the air baffles (7) that follow one another in the longitudinal direction (S) of the combustion chamber are connected to one another by means of tab-bar arrangements (9b, 9c) in such a way that connecting tabs (16a, 16b; 21a, 21b) are formed at the opposite boundaries of the air baffles (7) that follow one another in the longitudinal direction (S) of the combustion chamber, which extend into the combustion space (8) and pass through a common retaining plate (17), which forms a form fit in the longitudinal direction (S) of the combustion chamber between the connecting tabs (16a, 16b; 21a, 21b) and is secured by means of a connecting bar (18) which passes through at least one of the connecting tabs (16a, 16b; 21a, 21b) on the side of the retaining plate (17) facing the combustion space (8).
9. Combustion chamber (4) according to claim 8, wherein at least a portion of the connecting tabs (21a, 21b) which pass through a common retaining plate (17) lie one above the other as viewed in the direction in which the connecting bar (18) is pushed through.
10. Combustion chamber (4) according to one of claims 8 to 9, wherein at least a portion of the connecting tabs (16a, 16b) which pass through a common retaining plate (17) lie next to one another as viewed in the direction in which the connecting bar (18) is pushed through.
11. Combustion chamber (4) according to one of claims 8 to 10, wherein the common retaining plate (17) is secured with exactly one connecting bar (18) which passes through each of the connecting tabs (16a, 16b; 21a, 21b) penetrating the retaining plate (17).
12. Combustion chamber (4) according to claim 10 and according to claim 11, wherein the connecting tabs (16a, 16b), which pass through a common retaining plate (17) and are located next to one another, as viewed in the direction in which the connecting bar (18) is pushed through, together form a passage opening for the connecting bar (18).
13. Combustion chamber (4) according to one of claims 8 to 12, wherein the connecting bars (18) pass through at least a portion of the connecting tabs (21a, 21b) in the longitudinal direction (S) of the combustion chamber.
14. Combustion chamber (4) according to one of claims 8 to 13, wherein the connecting bars (18) pass through at least a portion of the connecting tabs (16a, 16b) in the circumferential direction of the combustion chamber.
15. Combustion chamber (4) according to one of the preceding claims, wherein at least a portion of the fastening bars (11) and/or connecting bars (18) strikes with a stop surface in a form-fitting manner in the direction of penetration against at least one of the fastening tabs (10) or connecting tabs (16a, 16b; 21a).
16. Combustion chamber (4) according to one of the preceding claims, wherein at least a portion of the fastening bars (11) and/or connecting bars (18) provided with a material application applied exclusively to its surface by welding after the mounting of the bar (11; 18), in particular by means of one or several welding points (20), is secured in a form-fitting manner against removal from the intended position.
17. Combustion chamber according to one of the preceding claims, wherein at least a portion of the fastening bars and/or connecting bars is secured in the intended position with a material bond by a welding produced after the mounting of the bar between the bar and a fastening or connecting tab and/or a retaining plate.
18. Combustion chamber (4) according to one of the preceding claims, wherein at least a portion of the air baffles (7) has a profile running in the longitudinal direction (S) of the combustion chamber, such that they form flow channels extending in the longitudinal direction (S) of the combustion chamber on their outer sides.
19. Combustion chamber (4) according to claim 7 and according to claim 18, wherein at least a portion of the air baffles (7) following one another, as viewed in the longitudinal direction (S) of the combustion chamber, is profiled in such a way that their mutually facing boundaries (14) pointing towards the hot air outlet end (B) form air outlet openings (15) from a flow channel extending behind them.
20. Combustion chamber (4) according to claim 19, wherein the air baffles (7) following one another, as viewed in the longitudinal direction (S) of the combustion chamber, whose mutually facing boundaries (14) form the air outlet openings (15) pointing towards the hot air outlet end (B), are connected to one another by means of tab-bar arrangements (9b) in such a way that connecting tabs (16a, 16b) are formed in the edge regions on the opposite boundaries (14) of the air baffles (7) in the longitudinal direction (S) of the combustion chamber, and these extend into the combustion space (8) and in each case pass through a common retaining plate (17), which creates a form fit in the longitudinal direction (S) of the combustion chamber between the respective connecting tabs (16a, 16b) and is secured in each case by means of a connecting bar (18) which passes through the respective connecting tabs (16a, 16b) on the side of the retaining plate (17) facing the combustion space (8).
21. Combustion chamber (4) according to claim 20, wherein the connecting tabs (16a, 16b), which each pass through the common retaining plate (17), as viewed in the direction of penetration of the connecting bar (18), lie next to each other and together form a passage opening for a common connecting bar (18), which passes through the connecting tabs (16a, 16b) in the circumferential direction of the combustion chamber.
22. Combustion chamber (4) according to claim 7 and according to claim 18, wherein at least a portion of the air baffles (7) following one another, as viewed in the longitudinal direction (S) of the combustion chamber, is profiled in such a way that their mutually facing boundaries (14) adjoin one another in an essentially continuous manner, and in particular that at least a portion of these air baffles (7) has air outlet openings (19) pointing towards the combustion space (8) from a flow channel extending behind them.
23. Combustion chamber (4) according to one of claims 19 to 21 and according to claim 22, wherein the air baffles (7), which have air outlet openings (19) pointing towards the combustion space (8) from a flow channel extending behind them, lie, as viewed in the longitudinal direction (S) of the combustion chamber, between the hot gas outlet end (B) and the air outlet openings (15) pointing towards the hot air outlet end (B) .
24. Combustion chamber (4) according to one of claims 22 to 23, wherein the air baffles (7) following one another, as viewed in the longitudinal direction (S) of the combustion chamber, which are profiled in such a way that their mutually facing boundaries (14) adjoin one another in an essentially continuous manner, are connected to one another by means of tab-bar arrangements (9c) in such a way that connecting tabs (21a, 21b) are formed in the central regions on the opposite boundaries (14) of the air baffles (7) in the longitudinal direction of the combustion chamber, tabs which extend into the combustion space (8) and in each case pass through a common retaining plate (17), which creates a form fit in the longitudinal direction (S) of the combustion chamber between the respective connecting tabs (21a, 21b) and each is secured by means of a connecting bar (18), which passes through the respective connecting tabs (21a, 21b) on the side of the retaining plate (17) facing the combustion space (8).
25. Combustion chamber (4) according to claim 24, wherein the connecting tabs (21a, 21b), which each pass through the common retaining plate (17), lie one above the other as viewed in the direction of penetration of the connecting bar (18) and are passed through by a common connecting bar (18) in the longitudinal direction (S) of the combustion chamber.
26. Hot gas generator (2) for an asphalt production plant (1), comprising a combustion chamber (4) according to one of the preceding claims and a burner (5) for generating a hot gas flow through the combustion chamber (4).
27. Plant (1) for the production of asphalt, comprising a hot gas generator (2) according to claim 26 and a drum dryer (3), in particular a countercurrent drum dryer (3), which is or can be charged with hot gas with the hot gas generator (2).
28. Use of the plant (1) according to claim 27 for drying and heating granular mineral and/or recycling asphalt material for asphalt production.
29. Method for fastening air baffles (7) in a base body (6) of a combustion chamber (4) for a hot gas generator (2), comprising the steps:

    a) providing a drum-like base body (6) of a combustion chamber (4) for a hot gas generator (2) with fastening tabs (10) extending radially inwards therein for fastening air baffles (7);

    b) arranging air baffles (7) in the base body (6) in such a way that they form the radial boundaries of the combustion space (8) of the combustion chamber (4) as intended, wherein the fastening tabs (10) between opposite boundaries (13) of the air baffles (7) are arranged and/or pass through the air baffles (7) and wherein the fastening tabs (10) extend radially beyond the air baffles (7) into the combustion space (8);

    c) pushing through the ends of the fastening tabs (10) extending into the combustion space (8) with fastening bars (11) in such a way that a form fit is created in the radial direction between the fastening tabs (10) and the air baffles (7).
30. Method according to claim 29, wherein the air baffles (7) are arranged in the base body (6) in such a way that at least a portion of the fastening tabs (10) are arranged between boundaries (13) of the air baffles (7) running in the longitudinal direction (S) of the combustion chamber.
31. Method according to claim 30, wherein the ends of the fastening tabs (10) which extend into the combustion space (8) and are arranged between boundaries (13) of the air baffles (7) running in the longitudinal direction (S) of the combustion chamber, are passed through with fastening bars (11) in the circumferential direction of the combustion chamber.
32. Method according to one of claims 29 to 31, wherein retaining plates (12) are arranged between the fastening bars (11) and the sides of the air baffles (7) facing the combustion space (8), through which the respective fastening tabs (10) pass.
33. Method according to claim 32, wherein the retaining plates (12) are arranged in such a way that they rest on the insides of the air baffles (7).
34. Method according to one of claims 32 to 33, wherein on the inside of the base body (6) there are stop surfaces (22) against which the air baffles (7) strike or can strike, pointing outwards in the radial direction, and wherein the retaining plates (12) are arranged at such a distance (a) from these stop surfaces (22) that the air baffles (7) can move radially between these stop surfaces (22) and the retaining plates (12) by a certain amount of clearance (d), and in particular, wherein the clearance (d) is at least 3 mm, in particular at least 5 mm.
35. Method for connecting air baffles (7) following one another in the longitudinal direction (S) of the combustion chamber in a base body (6) of a combustion chamber (4) for a hot gas generator (2), comprising the steps:

    a) providing air baffles (7) with connecting tabs (16a, 16b; 21a, 21b) which protrude at the ends from the surface of the respective air baffle (7) intended to form a combustion chamber boundary;

    b) arranging the air baffles (7) in a base body (6) of a combustion chamber (4) for a hot gas generator (2) in such a way that the air baffles (7) form a radial boundary of the combustion space (8) of the combustion chamber (4) as intended, wherein the end connecting tabs (16a, 16b; 21a, 21b) of air baffles (7) following one another in the longitudinal direction (S) of the combustion chamber are opposite and/or adjoin one another;

    c) arranging one retaining plate (17) with a passage opening on the respective opposite and/or adjoining connecting tabs (16a, 16b; 21a, 21b) in such a way that the connecting tabs (16a, 16b; 21a, 21b) push through the passage opening of the retaining plate (17) and extend beyond the retaining plate (17) into the combustion space (8), wherein the retaining plate (17) creates a form fit in the longitudinal direction (S) of the combustion chamber between the connecting tabs (16a, 16b; 21a, 21b); and

    d) securing the respective retaining plate (17) by means of a connecting bar (18) which passes through at least one of the connecting tabs (16a, 16b; 21a, 21b) on the side of the retaining plate (17) facing the combustion space (8).
36. Method according to one of claims 27 to 35, wherein at least a portion of the fastening bars (10) and/or connecting bars (16a, 16b; 21a, 21b) provided with a material application (20) applied exclusively to the surface of the bar by welding after the mounting of the bar, in particular with one or more welding points (20), is secured in a form-fitting manner against removal from the intended position.

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