WO2023217632A1

WO2023217632A1 - Receiving device for solar radiation having a container for heating a heat transfer medium in a solar thermal power plant

Info

Publication number: WO2023217632A1
Application number: PCT/EP2023/061848
Authority: WO
Inventors: Johannes CLAR; Jens Rheinländer
Original assignee: Deutsches Zentrum für Luft- und Raumfahrt e.V.
Priority date: 2022-05-11
Filing date: 2023-05-04
Publication date: 2023-11-16
Also published as: DE102022111801A1

Abstract

The invention relates to a receiving device (110) for solar radiation (112), having a container (200) for heating a heat transfer medium (210) in a solar thermal power plant, having an at least double-walled housing (220) which extends in a longitudinal direction (215), surrounds an interior space (208) and has an outer wall (206) and an inner wall (218) surrounded by said outer wall, wherein the inner wall (218) is formed from a multiplicity of surface segments (10) which are joined together gaplessly as viewed in a radial direction (238) that is transverse with respect to the longitudinal direction (215), wherein front faces (12, 14, 16, 18) of respectively adjacent surface segments (10) form an overlap (50) at least in a peripheral direction (242).

Description

title

Receiver device for solar radiation with a container for heating a heat transfer medium in a solar thermal power plant

State of the art

The invention relates to a receiver device for solar radiation with a container for heating a heat transfer medium in a solar thermal power plant.

Prior art solar radiation receiver devices are known as solar particle receivers for solar tower power plants. Such receiver devices use a rotating hollow cylindrical container in which a closed film of ceramic particles with a diameter of typically 1 mm or smaller forms as a heat transfer medium on the inner wall of the rotating cylinder. This particle film is heated to over 1000°C using concentrated solar radiation and then removed from the cylinder. The energy stored in the particles can be temporarily stored in an insulated container and used to generate electricity and/or in process heat applications. From DE 102014106320 A1 a device with a solar radiation receiver is known, which comprises a container that includes an outer wall and an interior space surrounded by the outer wall.

The device comprises a supply device for supplying a heat transfer medium to the interior of the container. The container is by means of a rotary drive device

Solar radiation receiver device rotatable about an axis of rotation in such a way that the heat transfer medium is guided along an inner wall of the container to form a heat transfer medium film. The device comprises at least one overflow element to form a rotationally symmetrical inner surface of the heat transfer medium film.

From WO 2021 233 526 A1 a heat exchanger device, in particular a solar radiation receiver, is known which comprises a heating chamber, which includes a wall and an interior space surrounded by the wall. The heat exchanger device further comprises a rotary drive device and a supply device for supplying a heat transfer medium to the interior of the heating chamber. The heating chamber can be rotated about an axis of rotation by means of the rotary drive device in such a way that the heat transfer medium can be guided along an inside of the wall of the heating chamber to form a heat transfer medium film. JP H02-302 582 A discloses refractory materials, in particular stones, which are used for the inner lining of rotary kilns. An interface between a refractory layer and an insulating layer of the materials has a wave shape, wherein the wave heads are connected in the circumferential direction of a shell of the rotary kiln and the rising and falling parts of the waves are perpendicular to the shell. Here, the adhesive force between the refractory layer and the insulating layer resists the frictional stress caused by the movement of the fired object during use.

A rotary drum furnace for incinerating waste is known from DE 12 70 728 A1. The rotary drum furnace includes an outer jacket made of jet and an inner jacket, which is formed by a large number of surface elements in the form of firebricks. The front sides of the firebricks overlap with grooves and grooves.

Disclosure of the invention

The object of the invention is to create a cost-effective and maintenance-friendly receiver device for solar radiation with a container for heating a heat transfer medium in a solar thermal power plant.

The task is solved by the features of the independent claim. Favorable refinements and advantages of the invention result from the further claims, the description and the drawing. According to one aspect of the invention, a receiver device for solar radiation with a container for heating a heat transfer medium in a solar thermal power plant is proposed, with an at least double-walled housing extending in a longitudinal direction, which surrounds an interior and which has an outer wall and an inner wall surrounded by it. Thermal insulation is arranged between the inner wall and the outer wall. The inner wall is formed from a plurality of surface segments which are joined together without gaps in the radial direction transversely to the longitudinal direction, with end faces of adjacent surface segments forming an overlap at least in one circumferential direction. The inner wall is at least partially supported against the outer wall in the radial direction by means of first spring elements. The thermal insulation forms the first spring elements.

The thermal insulation is designed to be at least partially resilient, at least in the radial direction. In the following, the terms insulation and/or thermal insulation and/or resilient insulation and/or elastic insulation are used for the insulation between the inner wall and the outer wall, since according to the invention the insulation between the inner wall and the outer wall has at least thermally insulating properties and resilient or .has elastic properties.

The container of the receiver device can, for example, be designed as a rotating drum in which a closed film of ceramic particles with a diameter typically of at most 1 mm is formed on the inner wall of the rotating cylinder. This particle film is heated to over 1000°C using concentrated solar radiation and then removed. Temperatures of, for example, 1100°C and more can occur. The energy stored in the particles can be temporarily stored in an insulated container and used to generate electricity and/or in process heat applications. The receiver device has an input for supplying the heat transfer medium to the container and an output for discharging the heat transfer medium from the container.

The special requirements for the structure and storage of the components of the rotating drum can advantageously be met by the receiver device according to the invention. On the inner wall along which the particles are guided, the running surface, which is usually made of a high-temperature alloy, has a temperature of at least 900 ° C for the particles during operation.

As a result, the inner wall, which is usually made of metal, experiences large thermal expansions in the axial and radial directions. The thermal insulation is located between the hot running surface of the inner wall and the outer wall of the container, so that the energy flows to the outer wall are advantageously reduced and the outer wall is usually a maximum of 100 ° C hot. This means that there are lower thermal expansions on the outer wall.

Another advantage of thermal insulation is that when the inner wall is installed or removed, the inner wall can slide on the thermal insulation or can be guided elastically by the thermal insulation. Furthermore, when installing or removing the outer wall, the outer wall can slide on the thermal insulation or be guided elastically by the thermal insulation. The differences in expansion are usually compensated for by a bearing structure between the inner wall and the outer wall. It must be ensured that the inner wall still has approximately the same axis of rotation as the outer wall and is not displaced against the outer wall. This is usually achieved with fixed bearings and floating bearings. Floating bearings block the relative movement in the direction of rotation. Fixed bearings block the relative movement in the direction of rotation and longitudinal direction.

In the proposed receiver device, on the other hand, the entire surface of the inner wall is composed of many individual, separate surface segments, for example ceramic elements, which are arranged at least partially overlapping. For this purpose, the tongue and groove principle can be used in the circumferential direction to connect curved or flat surface segments, so that adjacent surface segments abut one another at least partially overlapping on their end faces. In addition to the tongue and groove principle, other options for connecting the surface segments and also other options, for example a roof tile-like overlap, are also possible to create the overlap. This means that movement of the surface segments in a radial inward direction is no longer possible.

In addition, the inner wall is at least partially supported against the outer wall in the radial direction by means of the first spring elements. Here, a surface-applied force from the outside can permanently act on the inner wall. In this way, radial outward movement of the surface segments can be limited. Advantageously, the elastic insulation between the inner wall and the outer wall forms at least part of the spring elements and can be prestressed, so that the elastic insulation permanently exerts the surface-applied force from the outside onto the inner wall or has a surface on which the inner wall is supported , whereby the radial movement of the surface segments outwards can be limited.

In the event of radial thermal expansion, the insulation or the first spring elements are compressed. During the cooling process, the insulation or the spring elements can relax again.

In addition to the insulation, other suitable elements can form first spring elements. For example, additional spring elements made of metal or ceramic are conceivable.

It is therefore no longer necessary to provide an expansion gap to accommodate the radial expansion. In addition, thermal bridges no longer have to be passed through the insulation to support the inner wall in the radial direction.

The thermal insulation with a resilient effect can be achieved, for example, using polycrystalline wool, such as that used in exhaust gas catalytic converters. Even at temperatures above 1000°C, this material achieves sufficient elasticity to have a specified spring force on the surface segments. Commercially available products are available, for example, with wool compositions of 72% AI2O3 and 28% SiÜ2 or 80% AI2O3 and 20% SiÜ2 (determined by chemical analysis according to DIN EN 955-2; 4). A force of a few Newtons is sufficient as a preload force. However, other materials with comparable properties can also be used as thermal insulation.

Thermal insulation can advantageously fulfill several tasks. For example, the thermal insulation can reduce energy flows to the outer wall, so that there are lower thermal expansions on the outer wall. Furthermore, the thermal insulation can act as a sliding surface and/or as a guide, in particular as a resilient guide, when installing or removing the inner wall or the outer wall. Furthermore, the thermal insulation can act as a sliding surface and/or as a guide, in particular as a resilient guide, of the surface segments when the surface segments expand in the longitudinal direction. Furthermore, the thermal insulation can have an elastic effect or a supporting effect, which limits the radial movement of the inner wall outwards during operation.

Another advantage of using individual surface segments is the possible versatile shaping. In addition, the production of a large number of surface segments as identical parts can be realized cost-effectively.

According to a favorable embodiment of the receiver device, at least some of the surface segments can have a tongue-and-groove contour on their end faces, which interacts with a tongue-and-groove counter-contour of an adjacent surface segment. In this way, the surface segments can at least partially mesh with one another, so that they can no longer move inwards in the radial direction of the inner wall perpendicular to the surface of the surface segments. If the end faces of adjacent surface segments are pressed against each other, the surface segments form a stable, hollow cylindrical inner wall. However, a movement of the surface segments in a radial direction outwards due to thermal expansion is possible.

In alternative embodiments, part of the surface segments can be formed with grooves on two opposite end faces and another part can be formed with tongues on two opposite end faces. For a closed inner wall, the two embodiments can then be joined together alternately.

According to a favorable embodiment of the receiver device, some of the surface segments can be arranged to overlap like roof tiles on their end faces. In an alternative embodiment, the surface segments can form an overlap so that they can at least partially slide over one another during thermal expansion. The geometric dimensions of the inner wall can remain largely constant.

According to a favorable embodiment of the receiver device, the surface segments can have a ceramic material, in particular the surface segments can be formed from a ceramic material. The inner wall can advantageously be constructed from ceramic materials instead of a corresponding metal alloy. Due to the higher melting point of ceramics, higher application temperatures of over 1000°C can be achieved in order to be able to open up further process heat applications in this temperature range. Furthermore, when using ceramic materials, significant improvements in the service life of the inner wall are expected at temperatures up to 1000°C. Furthermore, ceramics have a lower coefficient of thermal expansion than metals, which means that the storage of the hot inner wall in the cold outer wall has to accommodate correspondingly less deformation path and can be spatially smaller.

According to a favorable embodiment of the receiver device, the inner wall can be arranged prestressed against the outer wall in the radial direction by means of the first spring elements, in particular by means of the elastic insulation which at least partially forms the first spring elements. In this way, an area-wide force can permanently act on the inner wall from the outside. In the event of radial thermal expansion, the first spring elements or the elastic insulation are then compressed. During the cooling process, the first spring elements or the elastic insulation can relax again.

According to a favorable embodiment of the receiver device, the surface segments can be flat or curved in the circumferential direction, in particular as part of a hollow cylinder jacket. With flat surface segments, the inner wall can be designed as a hollow body with a polygonal cross section. With curved surface segments, which correspond to a circular arc section, a hollow cylindrical shape of the inner wall can be achieved. According to a favorable embodiment of the receiver device, the inner wall can be supported in the circumferential direction against the outer wall by means of a fixed bearing. The fixed bearing can conveniently block the relative movement of the inner wall in the direction of rotation and, at the location of the fixed bearing, in the longitudinal direction. In the radial direction, however, movement is possible due to thermal expansion.

According to a favorable embodiment of the receiver device, the fixed bearing can be designed as a stop against the outer wall on the end face of the surface segments and/or as a fixation of the respective surface segments in the circumferential direction and in the longitudinal direction. The movement of the surface segments on which the fixed bearing is arranged is blocked in the circumferential direction and in the longitudinal direction. In this way, the relative movement of the inner wall in the direction of rotation and, at the location of the fixed surface segments, in the longitudinal direction can be conveniently blocked. For example, the fixed bearing can be arranged on surface segments on a lower end face of the lowest ring in the direction of gravity.

According to a favorable embodiment of the receiver device, the surface segments can have a tongue-and-groove contour on their end faces in the longitudinal direction, which interacts with a tongue-and-groove counter-contour of an adjacent surface segment. The tongue and groove principle can also be used between the connection of the surface segments in the longitudinal direction. In this way, a stable connection of adjacent surface segments in the radial direction can be achieved. When heated, the surface segments are pushed away from the fixed bearing of the inner wall by sliding on the elastic insulation. According to a favorable embodiment of the receiver device, the inner wall can be elastically supported in the longitudinal direction against the outer jacket by means of second spring elements. In particular, the second spring elements can be arranged on the end face of the lowest surface segments in the direction of gravity. When heated, the surface segments are pushed away from the fixed bearing of the inner wall in the longitudinal direction by sliding on the elastic insulation. Second spring elements, which are arranged opposite the fixed bearing, are tensioned. During cooling, the second spring elements push the surface segments back again. The second spring elements can be formed from elastic insulation or from metallic spring elements.

According to a favorable embodiment of the receiver device, elastic retraction elements can be arranged between at least some of the surface segments and the outer wall, by means of which the surface segments are prestressed or can be prestressed with spring force in the longitudinal direction against the outer wall. When heated, the surface segments are pushed away from the fixed bearing of the inner wall in the longitudinal direction by sliding on the elastic insulation. The retraction elements, which are arranged opposite the fixed bearing, are tensioned. During cooling, the retraction elements pull the surface segments back again. The retraction elements can be made from elastic insulation or from ceramic or metallic spring elements. According to a favorable embodiment of the receiver device, the first and/or second spring elements and/or the retraction elements can be designed as a spring element made of metal or ceramic or as thermal insulation, which is at least partially resilient. As a result, a defined spring effect can advantageously be achieved.

Here, at least some of the first spring elements are designed as thermal insulation; further first spring elements can be made of metal or ceramic or a further thermal insulation.

According to a favorable embodiment of the receiver device, the fixed bearing can be arranged in the longitudinal direction at an upper end of the inner casing in the direction of gravity or along a length of the inner wall. Conveniently, the position of the fixed bearing in the longitudinal direction can be arranged at any point along the entire length of the inner wall. For example, the fixed bearing can also be arranged on surface segments on a lower end face of the lowest ring in the direction of gravity.

According to a favorable embodiment of the receiver device, the surface segments can be arranged to overlap like a roof tile in the longitudinal direction. In the longitudinal direction, the rings formed in the circumferential direction can be constructed from surface segments, which are connected in the circumferential direction according to the tongue and groove principle, in such a way that they overlap one another. This means that the thermal expansion of the individual surface segments does not add up, since the surface segments partially slide over one another during thermal expansion in the longitudinal direction. The thermal expansion has only low values. According to a favorable embodiment of the receiver device, the surface segments can be positively connected to the thermal insulation in the radial direction. In order to maintain the position in the longitudinal direction of the inner wall, the surface segments can have a positive connection to the insulation between the inner wall and the outer wall.

According to a favorable embodiment of the receiver device, the surface segments can be connected to the outer wall by means of holding elements, in particular by means of metallic or ceramic holding elements. In an alternative embodiment, each individual surface segment can also be supported on the outer jacket by metallic or ceramic holding elements in order to maintain the position in the longitudinal direction of the inner wall.

According to a favorable embodiment of the receiver device, the end faces of the surface segments can have a triangular or a semicircular or a rectangular tongue-and-groove contour in the direction of a thickness expansion of the surface segments. In this way, a defined positive fit can be achieved for interlocking interlocking of adjacent surface segments.

According to a favorable embodiment of the receiver device, the surface segments can have a surface structure for a predetermined setting of a frictional resistance and/or rolling resistance of the heat transfer medium. As a result, a transfer of heat from solar radiation to the heat transfer medium can be varied and advantageously optimized. According to a favorable embodiment, the receiver device can comprise an aperture opening for the entry of solar radiation at one of the ends of the container, the container having a longitudinal axis which is oriented parallel or at an acute angle less than or equal to 90 ° to the direction of gravity. The container can be rotated about an axis of rotation in the intended direction of rotation by means of a rotary drive device in such a way that the heat transfer medium can be guided along an inner wall of the container to form a heat transfer medium film.

By means of such an arrangement, a heat transfer medium film can be formed particularly favorably on the inner wall of the rotating container, so that the most uniform possible heat transfer from the solar radiation entering through the aperture opening to the heat transfer medium can be achieved.

Advantageously, a homogeneous distribution of the heat transfer medium, which can in particular be designed as a particle stream, can be achieved at the beginning of the running surface of the heat transfer medium on the inner wall of the container. The more homogeneous the particle film is over the entire height of the inner wall, the more efficiently and evenly the particles are heated by solar radiation.

drawing

Further advantages result from the following drawing description. Exemplary embodiments of the invention are shown in the figures. The figures, the description and the claims contain numerous features in combination. The person skilled in the art will also expediently consider the features individually and combine them into further sensible combinations. They show, for example:

1 shows a receiver device for solar radiation with a container for heating a heat transfer medium in a solar thermal power plant in a transparent representation;

2 shows a housing of a container of the receiver device according to an embodiment of the invention in an isometric view;

Fig. 3 shows a cross section through the housing according to Fig. 2 with an inner wall and first spring elements;

4 shows a longitudinal section through an inner wall according to a first exemplary embodiment of the invention;

5 shows a longitudinal section through a container with an inner wall and an outer wall according to a further exemplary embodiment of the invention;

6 shows a longitudinal section through an inner wall according to a further exemplary embodiment of the invention; and

Fig. 7 shows a longitudinal section through an inner wall according to a further exemplary embodiment of the invention.

Embodiments of the invention

In the figures, components of the same type or with the same effect are numbered with the same reference numerals. The figures only show examples and are not to be understood as limiting. Directional terminology used below with terms such as “left”, “right”, “top”, “bottom”, “before”, “behind”, “after” and the like only serves to better understand the figures and is in no way intended to limit the represent generality. The components and elements shown, their design and use can vary according to the considerations of a person skilled in the art and can be adapted to the respective applications.

Figure 1 shows a receiver device 110 for solar radiation with a container 200 for heating a heat transfer medium 210 in a solar thermal power plant in a transparent representation.

The known receiver device 110 shown in Figure 1 comprises a container 200, which can be rotated about an axis of rotation 216 by means of a rotary drive device (not shown), as well as an input 300 for supplying the heat transfer medium 210 to an interior 208 of the container 200 and an output 400 for discharging the Heat transfer medium 210 from the container 200, both of which are connected to this container 200.

The container 200 has a longitudinal axis 214, which is oriented parallel or at an acute angle of typically less than or equal to 90° to the direction of gravity g, which is symbolized in the figure by a vertical arrow.

The container 200 in particular comprises a hollow cylindrical base body, which includes the circular cylindrical interior 208 surrounded by an outer wall 206. An inner wall 218 is arranged at a distance from the outer wall 206 and surrounds the interior 208. The container 200 has a thermal insulation, not shown, between the external outer wall 206 and the inner wall 218, so that temperatures of approximately 100 ° C can be maintained on the outside 240 of the container 200, although a temperature of the inner wall 218 is caused by the heated heat transfer medium 210 can be at least 900 ° C or higher, for example 1100 ° C.

The receiver device 110 has an aperture opening 416 for the entry of solar radiation 112 at the lower end 204 of the container 200.

The container 200 can be rotated about an axis of rotation 216 in the intended direction of rotation 236 by means of a rotary drive device in such a way that the heat transfer medium 210 is guided along the inner wall 218 of the container 200 to form a heat transfer medium film 212. The heat transfer medium 210 and the heat transfer medium film 212 are only indicated in FIG. 1 on the side of the inner wall 218 facing the interior 208.

The axis of rotation 216 encloses an angle 222 with the direction of gravity g, which can lie between 0° and 90° and can typically be approximately 45°, with the longitudinal axis 214 expediently being aligned coaxially with the axis of rotation 216.

The lower end 204 of the container 200 with respect to the direction of gravity g is designed to be open, so that the aperture opening 416 of the container 200 is formed, through which solar radiation 112 can enter the interior 208 of the container 200. To absorb the heat transferred by means of the solar radiation 112, the inner wall 218 of the container 200 is provided with a heat transfer medium 210, which is supplied via the entrance 300 through the feed opening 304 at the upper end 202 of the container 200.

Due to the rotation of the container 200 about the axis of rotation 216, the heat transfer medium 210 spreads on the inner wall 218 and thereby forms a heat transfer medium film 212.

The heat transfer medium 210 is fed into the interior 208 of the container 200 via the entrance 300, which is arranged at the upper end 202 of the container 200.

The heat transfer medium 210 can be transported, in particular conveyed, along the inner wall 218 from the end 202 at which it is supplied to an end 204 of the container 200 opposite this end 202, on which the aperture opening 416 is arranged, along the inner wall 218, in order to ensure a continuous flow of heat transfer medium 210 to be exposed to solar radiation 112 and thus heated.

The entrance 300 is formed from a conical front wall 302 and a conical rear wall 308 directed towards the interior 208 of the container 200, which are arranged coaxially and one above the other in the axial direction. A cone angle can be, for example, between 30° and 90°, preferably between 45° and 80°. Between the front wall 302 and the rear wall 308, guide elements 310 are arranged aligned in the radial direction 238, which are connected to the rear wall 308. In other exemplary embodiments, the guide elements 310 can also be connected to the inner wall 206 or overlapping alternately with the rear wall 308 and the inner wall 206. In the prior art, these guide elements 310 are straight.

The heat transfer medium 210 is introduced into the entrance 300 via a feed opening 304 arranged in a tip of the conical front wall 302 and is guided outwards between guide elements 310 in the radial direction 238 to the inner wall 218 of the container 200.

When the container 200 rotates in the direction of rotation 236, the heat transfer medium 210 is distributed on the inner wall 218 and guided downwards towards the exit 400 by gravity g.

The inner wall 218 of the container 200 usually has a friction-promoting device 234 so that the heat transfer medium 210 adheres as well as possible to the inner wall 218 and thus has a sufficiently long residence time in the interior 208 to absorb enough heat from the solar radiation 112.

The heated heat transfer medium 210 is then available for further use, for example for generating electricity in the solar thermal power plant.

The heat transfer medium 210 can advantageously be flowable or free-flowing. In particular, the heat transfer medium 210 can be formed by particles. In particular, it can be provided that the heat transfer medium 210 comprises particles or particles of sintered bauxite or is formed from particles or particles of sintered bauxite. The particles or particles may preferably have an average particle diameter of about 250 pm to about 1.8 mm. However, powdered media with much smaller grain sizes, such as cement powder, can also be used. Preferably, there is no agglomeration of particles or particles in the heat transfer medium up to at least approximately 800 ° C, in particular up to at least approximately 1,000 ° C. The particles preferably have a high sphericity. The sphericity, i.e. the ratio of the surface of a sphere of the same volume to the surface of the particle, can be in particular greater than approximately 0.8, in particular greater than approximately 0.9. Preferably the particles or particles can be thermal shock resistant.

The axis of rotation can advantageously be parallel or at an acute angle of less than or equal to 90°, preferably less than or equal to 80°, to the direction of gravity g. In particular, the axis of rotation can be coaxial with the longitudinal axis of the container.

A heat transfer medium film 212 can be formed particularly favorably on the inner wall of the rotating container, so that the most uniform possible heat transfer to the heat transfer medium can be achieved.

The container 200 can advantageously be made of steel. Due to the high temperatures of the heat transfer medium 210, the inner wall 218 is expediently made of a high-temperature-resistant stainless steel or another high-temperature alloy such as Inconel. Dimensions of the container 200 can, for example, be up to 8 m long and 5 m in diameter. The wall thickness of the inner wall 218 can be, for example, 6 mm, while the outer wall 206 can have a wall thickness of, for example, 12 mm. With such values, a weight of approximately 6 t up to 20 t can result for the container 200 with an associated thermal insulation between the inner wall 218 and the outer wall 206.

Ceramic fiber mats can advantageously be used as thermal insulation between the inner wall 218 and the outer wall 206. The outer wall 206 can additionally have thermal insulation made of microporous fibers, which can be pressed into plates, on an outer side 240.

With the specified dimensions, expansion values between the inner wall 218, which is heated to approximately 900 ° C by the heat transfer medium 210, and the outer wall 206, which is at a temperature of approximately 100 ° C, can be up to 70 mm in the radial direction 238 and up to 150 mm occur in the longitudinal direction 215.

Figure 2 shows a housing 220 of a container 200 of the receiver device 110 according to an exemplary embodiment of the invention in an isometric view.

The housing 220 extends in the longitudinal direction 215 and surrounds an interior 208. The housing 220 is double-walled and has an outer wall 206 and an inner wall 218 surrounded by it. Outer wall 206 and inner wall 218 are hollow cylindrical. The inner wall 218 is formed from a large number of surface segments 10 which are joined together without gaps in the radial direction 238 transversely to the longitudinal direction 215. With an inner diameter of the housing 220 of approximately 5 m, the surface segments 10 can, for example, have dimensions of 0.25 mx 0.25 m.

The surface segments 10 can expediently be designed as ceramic elements in the form of tiles. The dimensions can be, for example, 0.25 m x 0.25 m, with an inner diameter of the inner wall 218 of approximately 5 m.

A thermal insulation 20 is arranged between the inner wall 218 and the outer wall 206, which is designed to be at least partially resilient, at least in the radial direction. For this purpose, for example, polycrystalline wool can be used, such as that used in exhaust gas catalytic converters.

The radial outward movement can be limited by an elastic insulation 20 between the inner wall 218 and the outer wall 206. This insulation 20 can generate a preload in the form of first spring elements 40, so that a surface-applied force from the outside permanently acts on the inner wall 218. In the event of radial thermal expansion, the elastic insulation 20 is then compressed. During the cooling process, the insulation 20 can relax again. It is therefore no longer necessary to provide an expansion gap to accommodate the radial expansion. In addition, thermal bridges no longer have to be passed through the insulation 20 in order to support the inner wall 218 in the radial direction.

In an alternative exemplary embodiment, not shown, further first spring elements 40 can be arranged between the inner wall and the outer wall in addition to the elastic insulation 20. Figure 3 shows a cross section through the housing 220 according to Figure 2 with the inner wall 218 and the first spring elements 40. Insulation 20 and first spring elements 40 are shown schematically as spiral springs.

For the sake of clarity, reference symbols, as in the following figures, are only attached to individual components.

As can be seen in Figure 3, the surface segments 10 are arranged on the circumference of the inner wall 218 in such a way that end faces 12, 14 of adjacent surface segments 10 form an overlap 50 in the circumferential direction 242 and mesh with one another. The surface segments 10 each have a tongue-and-groove contour 24, 26 on their end faces 12, 14, which interacts with a tongue-and-groove counter-contour 25, 27 of an adjacent surface segment 10.

In the exemplary embodiment, the surface segments 10 are curved in the circumferential direction 242 in the form of a circular arc section, and thus form part of a hollow cylinder jacket.

In this exemplary embodiment, the end faces 12, 14, 16, 18 of the surface segments 10 have a triangular tongue-and-groove contour 24, 26 in the direction of a thickness extension 22 of the surface segments 10. Alternatively, it is also possible for the tongue and groove contour 24, 26 to be semicircular or rectangular or in another favorable shape. In this way, a defined positive fit for interlocking interlocking of adjacent surface segments 10 can be achieved.

The inner wall 218 is supported against the outer wall 206 in the radial direction 238 by means of the first spring elements 40. In particular, the thermal insulation 20 can form the first spring elements 40, which support the inner wall 218 against the outer wall 206.

The inner wall 218 can expediently be arranged prestressed against the outer wall 206 in the radial direction 238 by means of the first spring elements 40. In this way, a surface-applied force can permanently act on the inner wall 218 from the outside. In the event of radial thermal expansion, the first spring elements 40 are then compressed. During the cooling process, the first spring elements 40 can relax again.

The movement of the inner wall 218 due to thermal expansion is shown in FIG. 3 with an arrow 46.

Figure 4 shows a longitudinal section through an inner wall 218 according to a first exemplary embodiment of the invention.

The inner wall 218 is supported in the circumferential direction 242 by means of a fixed bearing 30 against the outer wall 206, not shown. The fixed bearing 30 can be designed to fix the respective surface segments 10 in the circumferential direction 242. The outer wall 206 is not shown. The fixed bearing 30 blocks movement of the inner wall 218 against the outer wall 206 in the circumferential direction 242 and, at the location of the respective surface segments 10 on which the fixed bearing 30 is arranged, in the longitudinal direction 215. A movement of the inner wall 218 in the radial direction 238 due to the However, thermal expansion is possible and can be made more difficult by the elastic insulation 20 (not shown) or by the first spring elements 40 (not shown). In this exemplary embodiment, the surface segments 10 also have a tongue-and-groove contour 26 on their end faces 16, 18 in the longitudinal direction 215, which interacts with a tongue-and-groove counter-contour 27 of an adjacent surface segment 10.

The tongue and groove principle can also be used between the connection of the surface segments 10 in the longitudinal direction 215. In this way, a stable connection of adjacent surface segments 10 in the radial direction 238 can be achieved.

The inner wall 218 is elastically supported in the longitudinal direction 215 against the outer jacket 206 by means of second spring elements 42. In the exemplary embodiment shown in FIG. 4, the second spring elements 42 are arranged on the end face 26 of the lowest surface segments 10 in the direction of gravity g.

When heated, the surface segments 10 are pushed away from the fixed bearing 30 of the inner wall 218 by sliding on the elastic insulation 20, not shown. The second spring elements 42, which are arranged opposite the fixed bearing 30, are tensioned. During cooling, the second spring elements 42 press the surface segments 10 back again. The second spring elements 42 can be formed from an elastic insulation 20 or from metallic spring elements.

The movement of the surface segments 10 in the longitudinal direction 215 due to the thermal expansion is shown in FIG. 4 with an arrow 48.

5 shows a longitudinal section through a container 200 with an inner wall 218 and an outer wall 206 according to a further exemplary embodiment of the invention. In this exemplary embodiment, the inner wall 218 also has surface segments 10, which are joined together according to the tongue and groove principle. However, elastic retraction elements 44 are arranged between at least some of the surface segments 10 and the outer wall 206, by means of which the surface segments 10 are prestressed or can be prestressed in the longitudinal direction 215 against the outer wall 206.

When heated, the surface segments 10 are pushed away in the longitudinal direction from the fixed bearing 30 of the inner wall 218 by sliding on the elastic insulation 20. The retraction elements 44, which are arranged opposite the fixed bearing 30, are tensioned. During cooling, the retraction elements 44 pull the surface segments 10 back again. The retraction elements 44 can be formed from an elastic insulation 20 or from ceramic or metallic spring elements.

The retraction elements 44 as well as the first and second spring elements 40, 42 of the previous exemplary embodiments can advantageously be designed as a spring element made of metal or ceramic or as a thermal insulation 20, which is at least partially resilient.

Here, retraction elements 44 can be formed from the elastic, thermal insulation 20, not shown.

Alternatively, in addition to the thermal insulation 20, the retraction elements 44 may be arranged between the inner wall and the outer wall. Alternatively, the retraction elements 44 can be partially formed from the elastic, thermal insulation 20; additional retraction elements 44 can also be arranged between the inner wall and the outer wall.

The movement of the surface segments 10 in the longitudinal direction 215 due to the thermal expansion is shown in FIG. 5 with an arrow 48.

The inner wall 218 is mounted against the outer wall 206 with a fixed bearing 30, not shown in FIG. The fixed bearing 30 can be arranged in the longitudinal direction 215 at an upper end 32 of the inner casing 218 in the direction of gravity g or along a length 28 of the inner wall 218. Conveniently, the position of the fixed bearing 30 in the longitudinal direction 215 can be arranged at any point along the entire length 28 of the inner wall 218.

Figure 6 shows a longitudinal section through an inner wall 218 according to a further exemplary embodiment of the invention.

The surface segments 10 are arranged to overlap like a roof tile in the longitudinal direction 215, with at least some of the surface segments 10 being arranged to overlap like a roof tile on their end faces 16, 18.

In the longitudinal direction 215, rings formed in the circumferential direction 242 from surface segments 10, which are connected in the circumferential direction 242 according to the tongue and groove principle, can be constructed in such a way that they overlap one another. This means that the thermal expansion of the individual surface segments 10 does not add up, since the surface segments 10 partially slide over one another during thermal expansion in the longitudinal direction 215. The thermal expansion has only low values. The movement of the surface segments 10 in the longitudinal direction 215 due to the thermal expansion is shown in FIG. 6 with an arrow 48. The overlap 50 is shown as an example on a surface segment 10 and can change due to the movement of the surface segments 10 in the longitudinal direction 215.

The surface segments 10 can expediently be positively connected to the thermal insulation 20 (not shown) in the radial direction 238. In order to maintain their position in the longitudinal direction 215 of the inner wall 218, the surface segments 10 can have a positive connection to the insulation 20 between the inner wall 218 and the outer wall 206.

In an alternative embodiment, the surface segments 10 can also be connected to the outer wall 206 by means of holding elements, in particular by means of metallic or ceramic holding elements. In order to maintain the position in the longitudinal direction of the inner wall 218, each individual surface segment 10 can also be supported on the outer jacket 206 by metallic or ceramic holding elements.

Figure 7 shows a longitudinal section through an inner wall 218 according to a further exemplary embodiment of the invention. The inner wall 218 is supported in the circumferential direction 242 and in the longitudinal direction 215 by means of a fixed bearing 30 against the outer wall 206, not shown. The fixed bearing 30 is designed as a stop against the outer wall 206 on the lower end face 26 of the lowest ring of the surface segments 10. The outer wall 206 as a counter bearing is not shown. The fixed bearing 30 blocks movement of the inner wall 218 against the outer wall 206 in the circumferential direction 242 and, at the location of the lowest surface segments 10 on which the fixed bearing 30 is arranged, in the longitudinal direction 215. A movement of the inner wall 218 in the radial direction 238 due to the However, thermal expansion is possible.

In this exemplary embodiment, as in the exemplary embodiments shown in FIGS. 4 and 5, the surface segments 10 have a tongue-and-groove contour 26 on their end faces 16, 18 in the longitudinal direction 215, which has a tongue-and-groove counter-contour 27 of an adjacent one Surface segment 10 interacts.

The inner wall 218 is elastically supported in the longitudinal direction 215 against the outer jacket 206 by means of second spring elements 42. In the exemplary embodiment shown in FIG. 7, the second spring elements 42 are arranged on the end face 16 of the uppermost surface segments 10 in the direction of gravity g.

When heated, the surface segments 10 are pushed away from the fixed bearing 30 of the inner wall 218 by sliding on the elastic insulation 20. The second spring elements 42, which are arranged opposite the fixed bearing 30, are tensioned. During cooling, the second spring elements 42 press the surface segments 10 back again. The second spring elements 42 can be formed from an elastic insulation 20 or from metallic spring elements.

The movement of the surface segments 10 in the longitudinal direction 215 due to the thermal expansion is shown in FIG. 7 with an arrow 48. In all exemplary embodiments, the surface segments 10 can advantageously have a surface structure for a predetermined setting of a frictional resistance and/or rolling resistance of the heat transfer medium 210. In this way, the speed at which heat transfer medium film 212 (see FIG. 1) slides downward on an inside of the inner wall 218 in the direction of gravity g can be influenced. As a result, a transfer of the heat from the solar radiation 112 to the heat transfer medium 210 can be varied and advantageously optimized.

Reference symbols

10 area segment

12 front side

14 front side

16 front side

18 front side

20 thermal insulation

22 thickness expansion

24 contour

25 counter contour

26 contour

27 counter contour

28 length

30 fixed camps

32 end

34 front side

40 first spring element

42 second spring element

44 retraction element

46 thermal expansion

48 thermal expansion

50 overlap

110 receiver device

112 solar radiation

200 containers

202 first end

204 second end

206 external wall

208 interior

210 heat transfer medium

212 heat transfer medium film 214 longitudinal axis

215 longitudinal direction

216 axis of rotation

218 interior wall

220 cases

222 angles

236 direction of rotation

238 radial direction

240 outside

242 circumferential direction

300 entrance

302 front wall

304 feed opening

308 back wall

310 guiding element

400 output

416 aperture opening

Claims

Expectations

1. Receiver device (110) for solar radiation (112) with a container (200) for heating a heat transfer medium (210) in a solar thermal power plant, with an at least double-walled housing (220) extending in a longitudinal direction (215), which has an interior ( 208) and which has an outer wall (206) and an inner wall (218) surrounded by it, a thermal insulation (20) being arranged between the inner wall (218) and the outer wall (206), the inner wall (218) consisting of a A plurality of surface segments (10) which are joined together without gaps in the radial direction (238) transversely to the longitudinal direction (215), with end faces (12, 14, 16, 18) of adjacent surface segments (10) overlapping at least in one circumferential direction (242). (50), wherein the inner wall (218) is at least partially supported against the outer wall (206) in the radial direction (238) by means of first spring elements (40), and wherein the thermal insulation (20) forms the first spring elements (40).

2. Receiver device according to claim 1, wherein at least some of the surface segments (10) have a tongue-and-groove contour (24, 26) on their end faces (12, 14, 16, 18), which has a tongue-and-groove counter-contour ( 25, 27) of an adjacent surface segment (10) interacts.

3. Receiver device according to claim 1 or 2, at least some of the surface segments (10) are arranged to overlap like a roof tile on their end faces (12, 14, 16, 18). Receiver device according to one of the preceding claims, wherein the surface segments (10) have a ceramic material, in particular are formed from a ceramic material. Receiver device according to one of the preceding claims, wherein the inner wall (218) is arranged biased against the outer wall (206) in the radial direction (238) by means of the first spring elements (40). Receiver device according to one of the preceding claims, wherein the surface segments (10) are flat or curved in the circumferential direction (242), in particular as part of a hollow cylinder jacket. Receiver device according to one of the preceding claims, wherein the inner wall (218) is supported in the circumferential direction (242) against the outer wall (206) by means of a fixed bearing (30). Receiver device according to claim 7, wherein the fixed bearing (30) acts as a stop against the outer wall (206) on the end face (18) of the surface segments (10) and/or as a fixation of the respective surface segments (10) in the circumferential direction (242) and in the longitudinal direction ( 215) is trained. Receiver device according to one of the preceding claims, wherein the surface segments (10) have a tongue-and-groove contour (26) on their end faces (16, 18) in the longitudinal direction (215), which is connected to a tongue-and-groove counter contour (27) of an adjacent one Surface segment (10) works together. Receiver device according to one of the preceding claims, wherein the inner wall (218) is elastically supported in the longitudinal direction (215) against the outer jacket (206) by means of second spring elements (42), in particular wherein the second spring elements (42) on the end faces (16, 18) the top or bottom surface segments (10) in the direction of gravity (g) are arranged. Receiver device according to one of the preceding claims, wherein between at least part of the surface segments (10) and the outer wall (206) elastic retraction elements (44) are arranged, by means of which the surface segments (10) with spring force in the longitudinal direction (215) against the outer wall (206 ) are prestressed or prestressed. Receiver device according to claim 10 or 11, wherein the first and / or the second spring elements (40, 42) and / or the retraction elements (44) are designed as a spring element made of metal or ceramic or as thermal insulation (20), which is at least partially resilient is. Receiver device according to one of claims 7 to 12, wherein the fixed bearing (30) is arranged in the longitudinal direction (215) at an upper end (32) of the inner casing (218) in the direction of gravity (g) or along a length (28) of the inner wall (218). is. Receiver device according to one of claims 1 to 8, wherein the surface segments (10) are arranged overlapping like a roof tile in the longitudinal direction (215). Receiver device according to claim 14, wherein the surface segments (10) are positively connected to the thermal insulation (20) in the radial direction (238). Receiver device according to claim 14, wherein the surface segments (10) are connected to the outer wall (206) by means of holding elements, in particular by means of metallic or ceramic holding elements. Receiver device according to one of the preceding claims, wherein the end faces (12, 14, 16, 18) of the surface segments (10) in the direction of a thickness extension (22) of the surface segments (10) have a triangular or a semicircular or a rectangular tongue and groove contour ( 24, 26). Receiver device according to one of the preceding claims, wherein the surface segments (10) have a surface structure for a predetermined setting of a frictional resistance and/or rolling resistance of the heat transfer medium (210). A receiver device according to any one of the preceding claims, comprising an aperture opening (416) for the entry of solar radiation (112) at one of the ends (202, 204) of the container (200); wherein the container (200) has a longitudinal axis (214) which is oriented parallel or at an acute angle less than or equal to 90° to the direction of gravity (g), the container (200) being rotated in a intended direction of rotation (236) by means of a rotary drive device such can be rotated about an axis of rotation (216) so that the heat transfer medium (210) can be guided along an inner wall (218) of the container (200) to form a heat transfer medium film (212).