Patent Publication Number: US-11650013-B2

Title: Conveying a material to be conveyed

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a 35 U.S.C. §§ 371 national phase conversion of PCT/EP2018/061298, filed May 3, 2018, the contents of which are incorporated herein by reference which claims priority of European Patent Application No. 17170804.3, filed May 12, 2017, the contents of which are incorporated by reference herein. The PCT International Application was published in the German language. 
     TECHNICAL FIELD 
     The invention relates to a conveying installation and a method for conveying a material for conveying. In particular, the invention relates to the conveyance of reactive and/or hot and/or abrasive material for conveying. 
     A reactive material for being conveyed means a material for being conveyed which reacts chemically and/or physically with environmental substances surrounding the conveying installation, for example with air, in particular with the oxygen of the air. In the conveyance of such a material, various demands are placed on its conveying installation. In the conveyance of hot material, the conveying mechanism of the conveying installation is also subjected to high temperatures, such that it must be cooled or must be fabricated from expensive heat-resistant materials. In the conveyance of such a reactive material and for example as a result of chemical reactions of the material being conveyed, it is possible that due to, for example, oxygen from the environment, harmful and/or environmentally damaging gas may escape from the material being conveyed, and/or the material being conveyed can heat up intensely as a result of the reactions, which can lead to material damage to the material being conveyed and/or to safety problems. In order to prevent contact of reactive material with, for example, oxygen, use is often made of an inert gas, for example nitrogen, in order to keep oxygen out of the environment of the material being conveyed. Furthermore, in the conveyance of such a material, dust often forms, which can likewise have a harmful and/or environmentally damaging effect and/or can be detrimental to sub-components of the conveying installation, and so the dust must be extracted from the conveying installation and disposed of. 
     US 2004/0063058 A1 discloses a multi-zone convection furnace in which gas from a cooling chamber of the furnace is conducted into one or more heating zones of the furnace in order to provide a specific thermal profile. The gas that is introduced from the cooling chamber into the one or more heating zones is of the same type of gas that is present in the heat zones, and is typically nitrogen. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to provide a conveying installation and a method for conveying a material for being conveyed which are improved in particular with regard to the conveyance of reactive, hot and/or abrasive material being conveyed. 
     A conveying installation according to the invention for conveying a material for being conveyed along a conveying path comprises an installation housing with a conveying chamber, in which at least the conveying path is arranged, and with at least one secondary chamber, which is connected by means of at least one passage opening to the conveying chamber and which has a fluid atmosphere which differs physically and/or chemically from a fluid atmosphere in the conveying chamber. The at least one passage opening and the fluid atmospheres in the conveying chamber and in the at least one secondary chamber are configured for setting a defined fluid flow in the installation housing. 
     A chamber of an installation housing here means a substantially closed cavity of the installation housing. A fluid atmosphere in a chamber means its physical and chemical characteristics, for example the chemical composition, the pressure or the temperature, of a fluid that is situated in the chamber. A fluid means a gas or a liquid. 
     A conveying installation according to the invention thus permits a defined fluid flow in an installation housing of the conveying installation. This is achieved by division of the installation housing into a conveying chamber and at least one secondary chamber, which chambers have mutually different fluid atmospheres and which are connected by at least one passage opening. Arrangement of the conveying path in a conveying chamber permits substantial encapsulation of the conveying path with respect to the environment, such that the material being conveyed is substantially partitioned off with respect to environmental substances, particularly oxygen, from the environment. The setting of a defined fluid flow by means of mutually different fluid atmospheres in the conveying chamber and in the at least one secondary chamber additionally makes it possible for environmental substances and in particular oxygen to be kept out of the region of the material for being conveyed, and permits the defined discharge of harmful and/or environmentally damaging gases and dust out of the conveying chamber along with the fluid flow. 
     One embodiment of the invention provides for the installation housing to have at least one fluid inlet and at least one fluid outlet and to be otherwise of fluid-tight design aside from the at least one fluid inlet and the at least one fluid outlet. Fluid-tightness means fluid-tightness that satisfies a technical specification. The substantially fluid-tight design of the installation housing restricts escape of fluid from the installation housing to the fluid outlets, such that only a relatively small amount of fluid escapes from the installation housing. Furthermore, the emergence of fluid through the defined fluid outlets makes it possible for fluid that emerges from the installation housing to be targeted and at least partially collected and fed back to the installation housing. In this way, the consumption and the costs of the fluid used are advantageously reduced. The substantially fluid-tight design of the installation housing furthermore advantageously reduces ingress of environmental substances surrounding the conveying installation into the installation housing. 
     A further embodiment of the invention provides for an end of the conveying chamber, which is arranged in the region of the start of a conveying path, to be closed or closable. In this way, the direction of the fluid flow can be easily aligned with the transport direction of the material being conveyed. 
     The invention furthermore provides at least one component of a conveying mechanism for the conveying to be arranged in at least one secondary chamber. This advantageously makes it possible for sensitive components of the conveying mechanism to not be arranged in the conveying chamber but rather in a secondary chamber, whereby the sensitive components may be removed from the influence of high temperatures, dust and/or corrosive gases in the conveying chamber. Thus, components of the conveying mechanism can be protected against often adverse fluid atmosphere in the conveying chamber by the components being relocated into a secondary chamber. Furthermore, arranging those components of the conveying mechanism in a secondary chamber can be utilized to relatively easily cool the components in the secondary chamber, for example by fluid that is conducted into the secondary chamber and/or by a separate cooling device. 
     A further embodiment of the invention provides for the conveying mechanism to have a traction mechanism drive with at least one traction mechanism which is arranged in a secondary chamber and by means of which carrier elements for conveying the material being conveyed are movable. The material for conveying is for example transported directly by the carrier elements or in containers arranged on the carrier elements. Here, for example, the carrier elements separate the conveying chamber from a secondary chamber in which at least one traction mechanism is arranged. Alternatively, the carrier elements are arranged in the conveying chamber and project through a passage opening into at least one secondary chamber, in particular into a secondary chamber which is arranged laterally at the conveying chamber and in which a traction mechanism is arranged. The traction mechanism drives and the carrier elements that are moved by the traction mechanism are particularly highly suitable for being so moved, inter alia, owing to their robustness and their low maintenance requirements, for transporting reactive, hot and/or abrasive material being conveyed. Arrangement of a traction mechanism in a secondary chamber protects the traction mechanism against high temperatures, dust and/or corrosive fluids in the conveying chamber. When a conveying chamber is separated from a secondary chamber in which at least one traction mechanism is arranged, the carrier elements can be used not only for transporting the material being conveyed but at the same time for partitioning off the secondary chamber from the conveying chamber. For a traction mechanism being in a secondary chamber arranged laterally of the conveying chamber, the traction mechanism is spatially further separated from the material being conveyed, which is advantageous in particular in the transport of hot material for conveying, because the traction mechanism is then heated less intensely by the material being conveyed, and that mechanism therefore also requires less intense cooling. 
     A further embodiment of the invention provides an opening width of at least one passage opening to vary along the course of the passage opening. Regions of a secondary chamber with relatively narrow passage openings are particularly advantageously suitable for cooling of components, which are arranged there in the narrow opening of the conveying mechanism by means of fluid conducted into the secondary chamber, because particularly high fluid flows of the fluid arise in the narrowed regions. Furthermore, regions of a secondary chamber with relatively narrow passage openings are particularly advantageously suitable for the introduction of fluid into the secondary chamber, because less fluid flows from the secondary chambers into the conveying chamber in these regions than in regions with further passage openings. As a result, the introduced fluid can be distributed over greater regions of the secondary chamber. By contrast, regions with relatively wide passage openings are advantageously suitable for targeted conducting of relatively large amounts of fluid into the conveying chamber and thus for more intensely influencing the fluid flow in the conveying chamber. Therefore, through targeted variation of the opening width of a passage opening, it is possible for suitable regions of the secondary chamber to be defined for the cooling of components of the conveying mechanism or of other components of the conveying installation, for example the above-stated carrier elements, for positioning of fluid inlets and for influencing of fluid flow in the installation housing. 
     A further embodiment of the invention provides a cooling device for cooling at least one secondary chamber. This makes it possible in particular for components of the conveying mechanism that are arranged in the secondary chamber to be cooled when cooling by means of the fluid is not provided or is not sufficient. 
     A further embodiment of the invention provides a fluid circuit system which comprises at least one secondary chamber and which is configured for conducting a fluid through at least one passage opening from the secondary chamber into the conveying chamber. Such a fluid circuit system makes it advantageously possible for the consumption of fluid to be further lowered, because fluid discharged from a secondary chamber is fed via the fluid circuit system back to a secondary chamber, such that the fluid remains in the fluid circuit system. 
     The fluid circuit system may include at least one heat exchanger for cooling a fluid fed to a secondary chamber. In this way, the fluid that is cooled by means of the heat exchanger and subsequently conducted into a secondary chamber can advantageously also be used for cooling components, arranged in the secondary chamber, of the conveying mechanism. 
     Furthermore, the conveying installation may have a fluid recycling unit for receiving fluid from the conveying chamber and for feeding fluid back into the conveying chamber, wherein the fluid may be fed back directly and/or via the fluid circuit system. The fluid recycling unit may have a fluid cleaning unit for cleaning the fluid received from the conveying chamber. In this way, fluid that emerges or is extracted from the conveying chamber can be at least partially collected and recycled by being fed back into the conveying chamber. Here, it is not necessary for fluid to be fed to the fluid recycling unit directly from the conveying chamber. It rather is also possible for fluid to be discharged from the conveying chamber into an apparatus connected downstream of the conveying installation, for example into a bunker into which the material for conveying is conveyed, and for the fluid to be fed from the apparatus to the fluid recycling unit. The consumption of fluid can advantageously be lowered in this way. Since fluid emerging or extracted from the conveying chamber often contains dust and/or gas that has escaped from the material being conveyed, a fluid cleaning unit can be advantageous for cleaning the fluid that is received from the conveying chamber. 
     A further embodiment of the invention provides a closed-loop control system for closed-loop control of a fluid flow from at least one secondary chamber into the conveying chamber in a manner dependent on a pressure difference between a pressure in the secondary chamber and a pressure in the conveying chamber. This enables the fluid flow to be advantageously set particularly accurately as required. 
     In a method according to the invention for operating a conveying installation according to the invention, a higher fluid pressure is set in each secondary chamber than in the conveying chamber. This causes fluid flows from each secondary chamber into the conveying chamber, and not in the opposite direction from the conveying chamber into a secondary chamber. The higher fluid pressure in each secondary chamber in relation to the pressure in the conveying chamber, and the resulting fluid flow from each secondary chamber into the conveying chamber, advantageously also prevents the ingress of fluid that has escaped from the material being conveyed, and/or of dust that has formed during the transport of the material being conveyed, into a secondary chamber. 
     In one embodiment of the method a fluid recycling unit recycles fluid from the conveying chamber to be fed back into the conveying chamber directly and/or via at least one secondary chamber. The consumption of fluid can be advantageously lowered. In particular, the fluid is cleaned in the fluid recycling unit before being fed back into the conveying chamber. It is advantageously possible to prevent dust and/or fluid that has escaped from the material being conveyed to pass back into the conveying chamber with the fed-back fluid. 
     The above-described characteristics, features and advantages of this invention, and the manner in which these are achieved, will become clearer and more clearly understandable in conjunction with the following description of exemplary embodiments, which will be discussed in more detail in conjunction with the drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    schematically shows a first exemplary embodiment of a conveying installation with a first exemplary embodiment of a fluid circuit system, 
         FIG.  2    schematically shows a second exemplary embodiment of a conveying installation, 
         FIG.  3    shows a perspective illustration of a third exemplary embodiment of a conveying installation, 
         FIG.  4    schematically shows a sectional illustration of the conveying installation illustrated in  FIG.  3   , 
         FIG.  5    shows a block diagram of a second exemplary embodiment of a fluid circuit system of a conveying installation, 
         FIG.  6    shows a block diagram of a third exemplary embodiment of a fluid circuit system of a conveying installation, 
         FIG.  7    shows a block diagram of a fourth exemplary embodiment of a fluid circuit system of a conveying installation, 
         FIG.  8    shows a block diagram of a fifth exemplary embodiment of a fluid circuit system of a conveying installation, and 
         FIG.  9    shows a sectional illustration of a fourth exemplary embodiment of a conveying installation. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Parts which correspond to one another are denoted by the same reference designations in the Figures. 
       FIG.  1    schematically shows a first exemplary embodiment of a conveying installation  1  for conveying a material being conveyed along a conveying path. The conveying installation  1  comprises an installation housing  3 , which has a conveying chamber  5  and a secondary chamber  7 . At least the conveying path is arranged in the conveying chamber  7 . The secondary chamber  7  is arranged laterally at the conveying chamber  5  and is connected to the conveying chamber  5  by multiple passage openings  9 . Furthermore, the conveying installation  1  has a fluid circuit system  11  which comprises the secondary chamber  7  and which is designed for conducting a fluid, for example an inert gas, through the passage openings  9  from the secondary chamber  7  into the conveying chamber  5 . Flow directions of the fluid are indicated in  FIG.  1    by arrows. Instead of multiple passage openings  9 , it is also possible for one continuous slot-like passage opening  9  to be provided. 
     The material being conveyed is for example a reactive and/or hot and/or abrasive material being conveyed. In particular, harmful and/or environmentally damaging fluid may escape from the material being conveyed, which fluid therefore should not escape in uncontrolled fashion into the environment. Furthermore, dust may form during the transport of the material being conveyed in the conveying chamber  5 . 
     The conveying chamber  5  and the secondary chamber  7  have fluid atmospheres which fluid atmospheres differ physically and/or chemically. In particular, the fluid atmosphere in the secondary chamber  7  has a higher fluid pressure than the fluid atmosphere in the conveying chamber  5 . Fluid flows through the passage openings  9  from the secondary chamber  7  substantially into the conveying chamber  5 , and do not flow in the opposite direction from the conveying chamber  5  into the secondary chamber  7 . The fluid atmosphere in the conveying chamber  5  may, in particular in the case of a hot material being conveyed, have a higher temperature than the fluid atmosphere in the secondary chamber  7 , and/or the atmosphere in the conveying chamber may contain gas that has escaped from the material being conveyed and/or may contain dust that forms during the transport of that material being conveyed. The relatively high fluid pressure in the secondary chamber  7  and the resulting fluid flow from the secondary chamber  7  into the conveying chamber  5  advantageously also prevent ingress of the gas and/or dust from the conveying chamber  5  into the secondary chamber  7 . 
     The conveying path runs in the conveying chamber  5  between a first conveying chamber end  13  and a second conveying chamber end  15 . In the region of the first conveying chamber end  13 , material being conveyed is introduced into the conveying chamber  5 . At the second conveying chamber end  15 , the material being conveyed is discharged from the conveying chamber  5 . The first conveying chamber end  13  is for example configured to be closed or closable, whereas the second conveying chamber end  15  has a first fluid outlet  17  through which the fluid flows out of the conveying chamber  5 , for example together with the material being conveyed. The installation housing  3  furthermore has a second fluid outlet  18  through which fluid circulating in the fluid circuit system  11  is discharged from the secondary chamber  7 . Furthermore, the installation housing  3  may have further fluid outlets  19  through which fluid can be extracted from the conveying chamber  5 , for example if a fluid pressure in the conveying chamber  5  overshoots a pressure threshold value. Such fluid outlets  19  may for example have in each case one safety element, for example a safety valve, for example if a safety study considers this to be necessary. 
     The installation housing  3  furthermore has a first fluid inlet  21 , through which fluid circulating in the fluid circuit system is fed into the secondary chamber  7 . Furthermore, the installation housing  3  may have further fluid inlets  22 , through which fluid can be fed to the conveying chamber  5 , for example in order to influence a fluid flow in the conveying chamber  5 . Aside from the fluid outlets  17  to  19  and the fluid inlets  21 ,  22 , the installation housing  3  is of fluid-tight design. In other exemplary embodiments, the first fluid inlet  21  and/or the second fluid outlet  18  may also be arranged at locations other than the locations of the secondary chamber  7  shown in  FIG.  1   , for example they may be interchanged with one another in relation to  FIG.  1   . 
     By means of this substantially fluid-tight design of the installation housing  3 , escape of fluid from the installation housing  3  is restricted to the fluid outlets  17  to  19 , such that an only relatively small amount of fluid escapes from the installation housing  3 . Furthermore, fluid that has been discharged from the second fluid outlet  18  is fed back to the secondary chamber  7  through the fluid circuit system  11  via the first fluid inlet  21 . Moreover, fluid emerging from the first fluid outlet  17  and/or from at least one further fluid outlet  19  may possibly be at least partially collected, fed to the fluid circuit system  11  (possibly after cleaning, see  FIG.  2    and  FIG.  8   ) and recycled. Altogether, it is thus possible for the amount of fluid to be fed to the installation housing  3  to be kept relatively low. In this way, the consumption of fluid and the costs for the fluid are advantageously reduced. 
     A further advantage of the substantially fluid-tight design of the installation housing  3  and of the higher fluid pressure in the secondary chamber  7  in relation to the conveying chamber  5  is that harmful and/or environmentally damaging fluid that has escaped from the material being conveyed can likewise emerge from the conveying chamber  5  only at the fluid outlets  17 ,  19  and can be disposed of there. The same applies to dust that is situated in the conveying chamber  5 . 
     Components of the conveying mechanism for conveying the material being conveyed are arranged in the secondary chamber  7 . 
     The fluid circuit system  11  conducts fluid through the secondary chamber  7 , out of the secondary chamber  7  through the second fluid outlet  18 , and, for example by means of pipelines, via a turbomachine  25  and optionally via a heat exchanger  27  and back into the secondary chamber  7  through the first fluid inlet  21 . Furthermore, the fluid circuit system  11  has a fluid feed  29 , through which fluid can be fed to the fluid circuit system  11 , particularly to replace fluid that is discharged from the secondary chamber  7  into the conveying chamber  5  through the passage openings  9 . 
     The turbomachine  5  is a blower or a pump, depending on whether the fluid is a gas or a liquid. 
     The optional heat exchanger  27  serves for cooling the fluid. It is advantageous in particular in cases in which a hot material being conveyed is transported in the conveying chamber  5  and also components, all of which are to be cooled, of a conveying mechanism for conveying the material being conveyed are arranged in the secondary chamber  7 . In these cases, the fluid conducted into the secondary chamber  7  and cooled by the heat exchanger  27  can advantageously also be used for cooling the components of the conveying mechanism arranged in the secondary chamber  7 . Alternatively or in addition, the conveying installation may have a separate cooling device (not illustrated) for cooling the secondary chamber  7 . For example, the cooling device may have a cooling pipe which is fillable with a coolant or may have multiple cooling pipes, wherein at least one cooling pipe may be situated within the secondary chamber  7 . 
       FIG.  2    schematically shows a second exemplary embodiment of a conveying installation  1 . The conveying installation  1  differs from the exemplary embodiment illustrated in  FIG.  1    substantially by a fluid recycling unit  70  for receiving fluid that emerges from the conveying chamber  5  through the fluid outlet  17 . The fluid recycling unit  70  has a fluid cleaning unit  72  for cleaning the fluid that is received from the conveying chamber  5 . A part of the cleaned fluid is fed back directly into the conveying chamber  5  via a fluid inlet  22 . The other part of the cleaned fluid is fed back into the conveying chamber  5  indirectly by being fed to the fluid circuit system  11  via the fluid feed  29 . In the ideal case, all of the fluid that emerges from the conveying chamber  5  is fed back into the conveying chamber  5 , such that no further infeed of fluid into the conveying installation  1  is necessary. 
     Modifications of the exemplary embodiment shown in  FIG.  2    may provide for the fluid recycling unit  70  to alternatively or additionally receive fluid emerging from the conveying chamber  5  from another fluid outlet  19 . Furthermore, provision may be made for fluid to be alternatively or additionally fed back directly into the conveying chamber  5  through the fluid outlet  17 . Further modifications of the embodiment shown in  FIG.  2    may provide for fluid to be fed back into the conveying chamber  5  either only indirectly via the fluid circuit system  11  or only directly. Furthermore, fluid may be fed to the fluid circuit system  11  at some other location instead of via the fluid feed  29 , for example upstream of the heat exchanger  27 , in order to cool the fluid. Furthermore, the fluid cleaning unit  72  may be omitted if cleaning of the fluid is not necessary. 
       FIGS.  3  and  4    show a third exemplary embodiment of a conveying installation  1  for conveying a material being conveyed along a conveying path.  FIG.  3    shows a perspective view of the conveying installation  1 .  FIG.  4    shows a sectional illustration of the conveying installation  1 . 
     The conveying installation  1  comprises an installation housing  3 , which has a conveying chamber  5 , three secondary chambers  6  to  8 , and two additional chambers  31 ,  32 . 
     The conveying chamber  5  is of a generally ring-shaped form including two horizontally running horizontal portions  34 ,  36  and two vertically running diverting portions  38 ,  40 . The lower horizontal portion  34  runs below and is spaced apart from an upper horizontal portion  36 . The diverting portions  38 ,  40  form oppositely situated conveying chamber ends  13 ,  15  of the conveying chamber  5  and each diverting portion connects the two horizontal portions  34 ,  36  to one another. The conveying path runs in the upper horizontal portion  36  of the conveying chamber  5  between a first conveying chamber end  13  formed by a first diverting portion  38  and a second conveying chamber end  15  formed by a second diverting portion  40 . In the vicinity of the first conveying chamber end  13 , the installation housing  3  has a charging inlet  42  which is arranged above the upper horizontal portion  36 , through which material being conveyed is introduced into the conveying chamber  5 . In the region of the second conveying chamber and  15 , the installation housing  3  has a discharge opening  44  which is arranged below the second diverting portion  40  and through which material being conveyed is discharged out of the conveying chamber  5 . 
     The secondary chambers  6  to  8  are each of ring-shaped form. The conveying chamber  5  runs around a first secondary chamber  6 , wherein a bottom side of the upper horizontal portion  36 , a top side of the lower horizontal portion  34  and the two diverting portions  38 ,  40  of the conveying chamber  5  join the first secondary chamber  6 . A second secondary chamber  7  and a third secondary chamber  8  are arranged at different sides of the first secondary chamber  6  and each adjoins an outer side of the first secondary chamber  6  along the entire ring-shaped course thereof. 
     The conveying chamber  5  and the first secondary chamber  6  are separated from one another by carrier elements  46 , which transport the material being conveyed. The material being conveyed is for example transported directly by the carrier elements  46  or in containers arranged on the carrier elements  46 . The carrier elements  46  are configured for example as carrier plates. Traction mechanisms  48  are arranged in the first secondary chamber  6 . Each traction mechanism runs in encircling fashion within the first secondary chamber  6  along its ring-shaped course and each is connected to the carrier elements  46 . The traction mechanisms  48  are for example configured as drive chains. The carrier elements  46  are movable with the traction mechanisms  48  along a closed path, which comprises the conveying path, in the installation housing  3 . Each traction mechanism  48  runs, below the upper horizontal portion  36  and above the lower horizontal portion  34  of the conveying chamber  5 , rectilinearly between two diverting regions  50 ,  52  which are each situated in the region of one of the conveying chamber ends  13 ,  15  and in which the traction mechanism  48  is diverted. 
     The traction mechanisms  48  are each driven by drive wheels  54 , each arranged in a diverting region  50 ,  52  of the traction mechanisms  48 . The traction mechanisms  48  and their drive wheels  54  form a traction mechanism drive, which move the carrier elements  46 . A respective one of the two additional chambers  31 ,  32  is arranged at each diverting region  50 ,  52 . The drive wheels  54  of the diverting region  50 ,  52  are arranged in the additional chambers. Each additional chamber  31 ,  32  adjoins the first secondary chamber  6 . For each drive wheel  54  arranged therein, each additional chamber has connecting openings  56  to the first secondary chamber  6 , through which connecting openings the drive wheel  54  projects into the first secondary chamber  6 . 
     The second secondary chamber  7  and the third secondary chamber  8  are each connected by a passage opening  9 , which opening for example, runs in a ring-shaped encircling fashion and is of slot-like form, to the conveying chamber  5  and to the first secondary chamber  6 . The carrier elements  46  project through the passage openings  9  into the second secondary chamber  7  and into the third secondary chamber  8 . Guide wheels  58  are arranged in the second secondary chamber  7  and in the third secondary chamber  8  which guide the carrier elements  46 . At least one secondary chamber  6  to  8  may furthermore additionally be connected by at least one further passage opening  10  to the conveying chamber  5 . For example, further passage openings  10  between the first secondary chamber  6  and the conveying chamber  5  may be realized by gaps between the carrier elements  46 . 
     Analogously to the first exemplary embodiment illustrated in  FIG.  1   , the installation housing  3  has fluid outlets  17  to  19  and fluid inlets  21 ,  22 . A first fluid outlet  17  coincides for example with the discharge opening  44 . Furthermore, the second secondary chamber  7  and/or the third secondary chamber  8  may have at least one second fluid outlet  18 , and/or the conveying chamber  5  may have at least one further fluid outlet  19 . Furthermore, the second secondary chamber  7  and/or the third secondary chamber  8  may have at least one first fluid inlet  21 , and/or the conveying chamber  5  and/or the first secondary chamber  6  and/or at least one additional chamber  31 ,  32  may have at least one further fluid inlet  22 , wherein, for example, the charging inlet  42  may be a fluid inlet  22 . 
     As in the first exemplary embodiment illustrated in  FIG.  1   , the installation housing  3  is of fluid-tight design, aside from the fluid outlets  17  to  19  and the fluid inlets  21 ,  22 . This has the advantages described above with regard to a reduced fluid amount requirement and a controlled discharge and disposal of gas and dust from the conveying chamber  5 . 
     Further, the conveying chamber  5  and the secondary chambers  6  to  8  have, as in the first embodiment in  FIG.  1   , fluid atmospheres which differ physically and/or chemically. In particular, the fluid atmospheres in each secondary chamber  6  to  8 , which are connected to the conveying chamber  5  by means of at least one passage opening  9 ,  10 , have a higher fluid pressure than the fluid atmosphere in the conveying chamber  5 . This achieves that fluid, dust and gas that has escaped from the material for being conveyed do not flow directly out of the conveying chamber  5  into the secondary chambers  6  to  8 , but instead flow in the conveying chamber  5  in a controlled manner to the fluid outlets  17  to  19 . Furthermore, the components of the conveying mechanism that are arranged in the secondary chambers  6  to  8 , in particular the traction mechanisms  48  and drive wheels  54 , can be cooled by fluid that is conducted into the secondary chambers  6  to  8 . The opening widths of the passage openings  9 ,  10  may vary along the courses of the passage openings  9 ,  10 . For example, the slot-like passage openings  9  may be wider in the diverting regions  50 ,  52  of the traction mechanisms  48  than between the diverting regions  50 ,  52 . Regions of the secondary chambers  6  to  8  with relatively narrow passage openings  9 ,  10  are particularly advantageously suitable for the cooling of components of the conveying mechanism arranged in the secondary chambers by fluid in the secondary chambers  6  to  8 . Such components include the traction mechanisms  48  and drive wheels  54 , because particularly high fluid flows of the fluid arise in those regions in the secondary chamber. Furthermore, regions of the secondary chambers  6  to  8  with relatively narrow passage openings  9 ,  10  are particularly advantageously suitable for the introduction of fluid into the secondary chambers  6  to  8 , because less fluid flows from the secondary chambers  6  to  8  into the conveying chamber  5  in these regions than in regions with relatively wide passage openings  9 ,  10 , such that the introduced fluid can be distributed over greater regions of the secondary chambers  6  to  8 . 
     Analogously to the first exemplary embodiment illustrated in  FIG.  1   , the exemplary embodiment shown in  FIGS.  3  and  4    may also have a fluid circuit system  11  to control and optimize the fluid flow.  FIGS.  4  to  7    show block diagrams of different embodiments of such fluid circuit systems  11 . 
     The exemplary embodiment of a conveying installation  1  illustrated in  FIGS.  3  and  4    may be modified in a variety of ways. For example, traction mechanisms  48  may be arranged below, above and/or to the side of the conveying chamber  5 , and/or a different number of traction mechanisms  48  may be provided, for example only one traction mechanism  48 . Further, separate additional chambers  31 ,  32  for the drive wheels  54  may be omitted. Further, the conveying path may also run at an angle with respect to the horizontal, instead of running horizontally, or may have a course which deviates from a straight course, for example an S-shaped or a Z-shaped course, wherein the installation housing  3  is designed correspondingly to the course of the conveying path. Furthermore, the fluid outlet  17  may also be operated as a (further) fluid inlet. 
       FIG.  5    shows a fluid circuit system  11  into which the secondary chambers  6  to  8  and the additional chambers  31 ,  32  are integrated. The fluid circuit system  11  conducts fluid through each secondary chamber  6  to  8  and each additional chamber  31 ,  32 , discharges fluid from the secondary chambers  6  to  8  and the additional chambers  31 ,  32 , and conducts the fluid via a turbomachine  25  and optionally via a heat exchanger  27  back to the secondary chambers  6  to  8  and/or to the additional chambers  31 ,  32 . Furthermore, fluid is conducted from the secondary chambers  6  to  8  through the passage openings  9 ,  10  into the conveying chamber  5 . The fluid circuit system  11  has a fluid feed  29 , through which fluid can be fed to the fluid circuit system  11 , in particular to replace fluid that is discharged from the secondary chambers  6  to  8  through the passage openings  9 ,  10  into the conveying chamber  5 . The first secondary chamber  6  has a higher fluid pressure than the other secondary chambers  7 ,  8 , than the additional chambers  31 ,  32  and than the conveying chamber  5 , such that fluid flows from the first secondary chamber  6  into the other secondary chambers  7 ,  8 , the additional chambers  31 ,  32  and the conveying chamber  5 . Furthermore, the second secondary chamber  7  and the third secondary chamber  8  have a higher fluid pressure than the conveying chamber  5 , such that fluid flows from the second secondary chamber  7  and the third secondary chamber  8  into the conveying chamber  5 . 
       FIG.  6    shows a fluid circuit system  11  which differs from the fluid circuit system  11  shown in  FIG.  5    only in that the secondary chambers  6  to  8  and the additional chambers  31 ,  32  have an identical fluid pressure, such that fluid is exchanged between the secondary chambers  6  to  8  and the additional chambers  31 ,  32 . The fluid pressure in the secondary chambers  6  to  8  is again higher than in the conveying chamber  5 , such that fluid flows from each secondary chamber  6  to  8  into the conveying chamber  5 . 
       FIG.  7    shows a fluid circuit system  11  which differs from the fluid circuit system  11  shown in  FIG.  6    only by a closed-loop control system  80  for the closed-loop control of fluid flows between the secondary chambers  6  to  8  and the conveying chamber  5 . The closed-loop control system  80  comprises pressure measuring devices  82  for detecting pressures in the secondary chambers  6  to  8  and the conveying chamber  5  and control units  84  for monitoring pressure differences between the pressures and for the closed-loop control of the fluid flows between the secondary chambers  6  to  8  and the conveying chamber  5  in a manner dependent on the pressure differences. The closed-loop control of the fluid flows is performed by an activation of control valves  86  of the fluid circuit system  11 . 
       FIG.  8    shows a fluid circuit system  11 , which differs from the fluid circuit system  11  shown in  FIG.  7    only in that fluid emerging from the conveying chamber  5  through fluid outlet  17 ,  19  is partially collected, and fed back to the fluid circuit system  11 , by a fluid recycling unit  70 . The fluid recycling unit  70  may optionally have a fluid cleaning unit  72 , for cleaning fluid that has emerged from the conveying chamber  5 , for example cleaning gas that has escaped from the material being conveyed and/or of dust, before being fed to the fluid circuit system  11 . 
       FIG.  9    shows a sectional illustration of a fourth exemplary embodiment of a conveying installation  1 . This exemplary embodiment differs from the exemplary embodiment shown in  FIGS.  3  and  4    substantially only in that the first secondary chamber  6  has been omitted and the conveying chamber  5  extends into a region which is occupied by the first secondary chamber  6  in the exemplary embodiment shown in  FIGS.  3  and  4   . The traction mechanisms  48 , which in the exemplary embodiment shown in  FIGS.  3  and  4    are arranged in the first secondary chamber  6 , are arranged in the secondary chambers  7 ,  8  in the exemplary embodiment shown in  FIG.  9   , wherein a traction mechanism  48  is arranged in each of the secondary chambers  7 ,  8 . 
     Analogously to the exemplary embodiment shown in  FIGS.  3  and  4   , the secondary chambers  7 ,  8  are each connected to the conveying chamber  5  by a slot-like passage opening  9  which runs in a ring-shaped encircling fashion. The carrier elements  46  project through the passage openings  9  and into the secondary chambers  7 ,  8 . In each secondary chamber  7 ,  8 , there are guide wheels  58  by which the carrier elements  46  are guided. 
     Analogously to the exemplary embodiment shown in  FIGS.  3  and  4   , each traction mechanism is driven by two drive wheels  54 , which are arranged in each case in a diverting region  50 ,  52  of the traction mechanism  48  and are in contact with the traction mechanism  48 . At each diverting region  50 ,  52 , there is again arranged an additional chamber  31 ,  32  in which the drive wheels  54  of the diverting region  50 ,  52  are arranged. Each additional chamber  31 ,  32  adjoins both secondary chambers  7 ,  8  and, for each of the drive wheels  54  arranged therein, each additional chamber has connecting openings  57  through which the drive wheel  54  projects into the respective secondary chamber  7 ,  8 , in which the traction mechanism  48  connected to the drive wheel  54  is arranged. 
     By contrast to the exemplary embodiment shown in  FIGS.  3  and  4   , the carrier elements  46  do not delimit the conveying chamber  5 , but rather are spaced apart from a conveying chamber wall  60  of the conveying chamber  5 . The conveying chamber wall  60  may have a thermal insulation layer  62 . 
     Relocation of the traction mechanisms  48  into the secondary chambers  7 ,  8 , simplifies the construction of the installation housing  3  in relation to the exemplary embodiment shown in  FIGS.  3  and  4   , owing to the omission of the first secondary chamber  6 , which, in that exemplary embodiment, forms a separate traction mechanism chamber for the traction mechanisms  48 . Furthermore, the cooling of the traction mechanisms  48 , which drive transport of hot material being conveyed, is simplified. First, cooling of the first secondary chamber  6  is omitted. Secondly, driving the transport of hot material for conveying, the traction mechanisms  48  are less intensely heated, and therefore also require less intense cooling, because the traction mechanisms  48  are no longer arranged at a central region of the carrier elements  46 , which region is particularly intensely heated by the material being conveyed. Instead, the traction mechanisms are arranged at the relatively cool edge regions of the carrier elements  46 , with a considerably greater spacing from the material for conveying. 
     The spacing of the carrier elements  46  from the conveying chamber wall  60  causes a substantially homogeneous fluid atmosphere to form above and below the carrier elements  46 . It is advantageous that temperature differences and turbulent flows within the conveying chamber  5  are reduced. The spacing of the carrier elements  46  from the conveying chamber wall  60  and thermal insulation of the conveying chamber wall  60  by thermal insulation layer  62  reduces heat losses from the conveying chamber  5 . In that case, during transport of hot material being conveyed, the temperature of the material can be more effectively kept at an approximately constant level along the conveying path. 
     The exemplary embodiment of a conveying installation  1  shown in  FIG.  9    may be modified such that the additional chambers  31 ,  32  may be omitted. For example, the secondary chambers  7 ,  8  may be enlarged, such that each drive wheel  54  is arranged in one secondary chamber  7 ,  8 . 
     Furthermore, the installation housing  3  may be designed for discharging material being conveyed that falls from carrier elements  46  during their conveyance along the conveying path, in a manner such that the conveying chamber  5  does not gradually become blocked by material being conveyed that falls from carrier elements  46 . For this purpose, as in  FIG.  9   , the base of the upper region of the conveying chamber  5  has a trough-like form and is inclined relative to the horizontal, such that material being conveyed that falls from carrier elements  46  can slide to a disposal opening in the conveying chamber wall  60 , for example an opening in the base of the upper region of the conveying chamber  5 , and can from there be discharged from the conveying chamber  5  through the disposal opening. Alternatively, the base of the upper region of the conveying chamber  5  may also have one continuous disposal opening. There are fluid-tight chutes arranged under that opening, fluid-tight chutes via which material being conveyed that falls from the carrier elements  46  is disposed of. The installation housings  3  of conveying installations  1  that are shown in  FIGS.  1  to  4    may also be similarly designed for discharging material being conveyed that falls from carrier elements  46  during the conveyance along the conveying path. 
     Although the invention has been illustrated and described in more detail on the basis of preferred exemplary embodiments, the invention is not restricted by the disclosed examples, and other variations may be derived from these by a person skilled in the art without departing from the scope of protection of the invention. 
     LIST OF REFERENCE DESIGNATIONS 
       1  Conveying installation 
       3  Installation housing 
       5  Conveying chamber 
       6  to  8  Secondary chamber 
       9 ,  10  Passage opening 
       11  Fluid circuit system 
       13 ,  15  Conveying chamber end 
       17  to  19  Fluid outlet 
       21 ,  22  Fluid inlet 
       25  Turbomachine 
       27  Heat exchanger 
       29  Fluid feed 
       31 ,  32  Additional chamber 
       34 ,  36  Horizontal portion 
       38 ,  40  Vertical portion 
       42  Charging inlet 
       44  Discharge opening 
       46  Carrier element 
       48  Traction mechanism 
       50 ,  52  Diverting region 
       54  Drive wheel 
       56 ,  57  Connecting opening 
       58  Guide wheel 
       60  Conveying chamber wall 
       62  Heat insulation layer 
       70  Fluid recycling unit 
       72  Fluid cleaning unit 
       80  Closed-loop control system 
       82  Pressure measuring device 
       84  Control unit 
       86  Control valve