HEATING DEVICE, HEATING SYSTEM, HEAT STORAGE DEVICE AND HEAT STORAGE SYSTEM

Description

[0001] The invention relates to a heat storage device and a heat storage system with such a heat storage device.

[0002] Heat storage devices are used in practice to store thermal energy, which can be made available, for example, to a power plant when needed. A known heat storage device according to the preamble of claim 1, as disclosed, for example, in DE 27 31 115 A1 or US 4 286 141 A, comprises a storage space in which a heat storage medium in the form of a bed or in the form of shaped blocks is arranged, through which hot air flows for charging. The hot air was previously heated to temperature, for example, by means of an electrically operated heating device. Excess electrical energy can be used for this purpose. However, the efficiency of such a heating device has not yet met the highest standards.For discharging, i.e. for dissipating the heat, the heat storage medium is flowed through with warm air or ambient air, which is heated in the heat storage medium and fed in heated form to a consumer, for example a steam generator of a turbine.

[0003] The invention is based on the object of creating a heat storage device with an effective hot air flow and a heat storage system with such a heat storage device.

[0004] This object is achieved according to the invention by the heat storage device having the features of claim 1.

[0005] In this context, a heating device for heating a gas stream is also provided, which comprises two electrical connection elements for connection to a power source and at least one heating plate unit with an inflow side and an outflow side, which comprises a plurality of heating plate strips which lie in the gas stream and each have a first end region and a second end region, wherein adjacent heating plate strips in the first end regions and the second end regions are each connected to one another via a conductive spacer structure.

[0006] The heating device thus comprises a plurality of heating plate strips arranged side by side or one above the other and connected to one another at their ends via the conductive spacer structure to create the heating plate unit or heating plate package. The heating plate strips of the heating plate package are electrically connected in parallel.

[0007] In this case, the term "heating strip" is to be understood in its full breadth and includes both elongated metallic sheets and elongated conductive ceramic layers which are connected to each other in their end regions via the conductive spacer structure.

[0008] The heating plate strips of a heating plate unit provide a large surface area for heat transfer between the heating device and the gas flow. This results in a large total cross-section, while at the same time, due to the parallel alignment of the heating plates relative to the direction of the gas flow, there is low flow resistance and high flow velocities are possible. This results in technically advantageous, low material temperatures at the metal strips during operation while maintaining high heating output.

[0009] In a special embodiment of the heating device, the heating plate strips of the heating plate unit are alternately structured and flat. The structured heating plate strips are, in particular, corrugated and, together with the flat heating plate strips, form a kind of honeycomb structure through which the gas flow can flow. It is also conceivable for the heating plate unit to comprise only corrugated or only flat heating plate strips.

[0010] Furthermore, it is advantageous for the inherent stability of the heating plate unit if the corrugated heating plate strips are supported with their wave crests on at least one adjacent flat heating plate strip.

[0011] The heating strips can have a smooth or a finely structured surface.

[0012] In a special embodiment, the spacer structure of the heating device comprises so-called shims arranged between adjacent heating strips and connecting them to one another. The shims serve to ensure that at least the flat heating strips are aligned parallel to one another; they thus form spacer plates that keep the end regions of adjacent heating strips at a distance.

[0013] To ensure that the end regions of the structured, and in particular corrugated, heating plate strips are aligned parallel to the end regions of the flat heating plate strips, the lining plates have a thickness that essentially corresponds to the amplitude of the corrugation. The connection between the heating plate strips and the lining plates can be made using conventional joining methods; for example, the heating plate strips and the lining plates are welded, soldered, and / or riveted together in the two end regions.

[0014] A preferred embodiment of such a heating device, which can provide a large flow cross-section, comprises at least two heating plate units, between which an electrically insulating partition wall is arranged, preferably made of a ceramic. Preferably, more than two, for example, six heating plate units are also provided, which can be connected in series in a meandering pattern.

[0015] The two heating plate units are preferably connected in series, but can also be connected in parallel. Furthermore, the two heating plate units are preferably connected to each other via a contact plate, which is in particular in contact with the front side of the connected heating plate units.

[0016] The contact plate that connects the two adjacent heating plate stacks is preferably welded or soldered to the heating plate stacks.

[0017] The heating plate units, which are arranged side by side in the heating device, are, in particular, identical, essentially rectangular assemblies arranged one behind the other in a meandering pattern within the heating device. The heating plate units can also be slightly curved in one direction to accommodate thermal expansion in a defined manner. The entire structure then has an at least approximately rectangular base area, with one side curved slightly inward and one side slightly outward.

[0018] The electrically insulating partition is preferably made of a ceramic, high-temperature-resistant material. For example, it consists of a fiber-reinforced ceramic or a ceramic fabric, and is designed in the form of a plate or a perforated plate.

[0019] In a special embodiment, the partition wall is made of a material made of cordierite-based ceramic.

[0020] The partition wall serves to ensure a meandering current path through the heating plate units connected in series.

[0021] The connection elements of the heating device are preferably also each formed from an electrically conductive plate or sheet. In this case, in particular, they can be aligned with the contact plate that connects two heating plate units.

[0022] The heating device can be connected to either a direct current or an alternating current voltage source and can be operated, for example, in the extra-low, low or medium voltage range at 110 V to 10 kV alternating current or at 12 V to 1.5 kV direct current.

[0023] For loading the heat storage device according to the invention, a heating system for a gas flow is also proposed, which comprises an inflow side and an outflow side and a heating arrangement which has at least one heating unit which comprises a heating device with an inflow base surface which is oriented at right angles to the gas flow, and at least one bearing element on which the heating device is arranged and which is permeable to the gas flow, so that the inflow base surface of the heating device can be flowed against by the gas flow or the gas flow can flow from the heating device through the bearing element.

[0024] The heating system therefore comprises at least one heating unit, which includes the heating device and at least one support element on which the heating device is arranged. The base area of ​​the heating device defines the flow cross-section of the gas stream that can be heated by the heating device. The support element serves as a support for the heating device.

[0025] In a preferred embodiment of the heating system, the bearing element of the heating unit is made of an electrically insulating, heat-resistant, and in particular ceramic material. The material forms a structure that allows the gas flow to pass through it. For example, the bearing element forming a support matrix is ​​made of a ceramic molded block with a honeycomb structure, of ceramic rods, of a plate, of a perforated plate, or of a differently designed component with an open structure. In particular, a fiber-reinforced ceramic can be used to manufacture the bearing element. A combination of different materials for manufacturing the bearing element is also conceivable.

[0026] In a special embodiment of the heating system, the bearing element is made of a cordierite-based honeycomb ceramic. The honeycombs preferably have a square or rectangular cross-section in the direction of flow.

[0027] Preferably, the bearing element has a support surface for the heating device which corresponds to the inflow base surface of the heating device.

[0028] In order to prevent unwanted bypass flows, the bearing element is provided in a preferred embodiment with side walls which laterally delimit the heating device and which are gas-tight at least in the transverse direction.

[0029] In a practical embodiment of the heating system, the side walls are formed integrally with the bearing element. However, it is also conceivable that the side walls represent separate components that are mounted on a base plate of the bearing element.

[0030] In a heating system that provides a large flow cross-section, several heating units are advantageously arranged next to one another within the heating arrangement. The heating arrangement thus comprises several bearing elements and several heating devices arranged next to one another and expediently electrically interconnected, for example, in series or parallel.

[0031] Furthermore, an advantageous embodiment of the heating system comprises at least two layers of heating units stacked one above the other. This creates a stack heater whose output, in a further special embodiment, can be adjusted to changing gas volume flows by selectively switching individual heating devices on and off, and in which a high thermal heating output can be achieved even with a limited flow cross-section of the heating system.

[0032] In particular, with the heating arrangement designed as a stack heater, very high air outlet temperatures of up to 1000 °C or even higher can be achieved.

[0033] In the case of heating units arranged one above the other, the side walls with which the bearing elements are provided also act as spacers between the individual bearing elements.

[0034] The side walls, which can be formed integrally with the bearing element or as separate ceramic or otherwise constructed components, create a defined chamber for the heating device so that it is securely positioned even when gas flows through at high velocities. In the stack heater described above, the chamber for the heating device is delimited at the top by a subsequent heating unit or by its bearing element. The uppermost heating unit layer can be delimited by a cover through which flow can pass, which forms the top side of the heating arrangement and is also preferably formed from at least one shaped block. The shaped block can have a square or rectangular outline and a honeycomb structure, the honeycombs of which have, in particular, a square or hexagonal channel cross-section.However, it is also conceivable that the cover consists of ceramic rods, ceramic plates, perforated plates or other types of gas-permeable components, which are made in particular of a fiber-reinforced ceramic.

[0035] To secure the individual layers of the heating arrangement or the mounting matrix formed by the bearing elements against undesirable relative displacement, it is advantageous if the contact surfaces between the bearing elements are each provided with a position lock, which, for example, consists of a projection that engages a recess in the adjacent bearing element. For example, the projection is shaped as a rib or a knob, whereas the corresponding recess is shaped as a depression or groove.

[0036] The side walls with which the bearing element is provided are preferably also designed to be gas-tight in the flow direction to prevent bypass flows adjacent to the inflow base surface of the heating device. For example, the side walls are sealed with a ceramic paper or the like.

[0037] In another specific embodiment, the heating system comprises a ceramic and / or metallic support structure on which the heating arrangement is arranged. For example, the support structure comprises a grid on which the heating arrangement rests. It is also conceivable for the support structure to comprise at least one shaped brick, at least one lightweight refractory brick, and / or a ceramic or metallic bed, preferably at least one honeycomb shaped brick. In any case, the support structure must be permeable to the gas flow.

[0038] To ensure a uniform gas flow across the free cross-section of the heating arrangement, the support structure can include static and / or adjustable throttle elements. A static throttle element is formed, for example, by a perforated sheet.

[0039] To shield the heating arrangement from the environment, the heating system preferably has a heating channel in which the heating arrangement is arranged. For thermal insulation from the outside, the heating channel, which can in particular be formed by a pipe or a rectangular channel, can have internal insulation.

[0040] To facilitate maintenance of the heating arrangement, the receiving channel can have a lateral opening closed by a detachable cover element. Furthermore, it can be advantageous for regulating the gas flows if the heating system according to the invention has a throttle device and / or a shut-off device on the inlet side and / or on the outlet side. These are formed, in particular, by valves and / or flaps. The gas flow can be regulated alternatively or additionally by regulating the speed of a fan.

[0041] The heating device of the heating system is preferably designed according to the heating device described in detail above.

[0042] Furthermore, the heating system preferably has a temperature measuring element on the outlet side, which also enables control of the gas outlet temperature. The temperature measuring element is preferably arranged at a minimal distance from the heating arrangement in an electrically insulated manner, so that the temperature of the gas stream after exiting the heating arrangement can be measured with the shortest possible time delay.

[0043] In a preferred embodiment, the temperature measuring element is a thermocouple or a PT100 with a jacketed tube, with its measuring tip located in the center of a circular, hexagonal, square, or rectangular measuring channel in the heating system cover arranged in the direction of flow, so that the temperature of the gas flow can be determined without any significant dead time. For example, the temperature measuring element is arranged in a horizontal bore in the cover. Additionally or alternatively, a temperature measuring element can also be arranged in the base plate of the bearing element.

[0044] The temperature of the gas flow at the outlet side can be controlled in various ways. Preferably, however, at a constant electrical heating output, the gas flow through the heating arrangement is throttled or increased according to the deviation between an actual and a target temperature measured at the outlet side using a throttle device at the duct inlet and / or duct outlet, and / or adjusted by changing the fan speed. This control method is particularly suitable for stationary operation with constant heating output.

[0045] In non-stationary operating conditions, for example during heating processes or changing inlet temperatures of the gas flow into the heating system, the gas outlet temperature can be controlled by adjusting the electrical heating power, for example by means of thyristor control or by switching on or off individual heating units or groups of heating units.

[0046] Furthermore, the heating system can comprise several heating arrangements of the type described above, each designed as a stack heater. These can be arranged side by side, one behind the other, and / or one on top of the other. The power supply can be provided with a multiphase current, so that the individual heating arrangements can be controlled specifically and switched on as needed.

[0047] The invention relates to a heat storage device. This heat storage device comprises a container with an interior space, which has a storage chamber in which a heat storage medium for storing thermal energy is arranged, wherein the container has a first opening through which a gas flow can be introduced into the interior space, and a second opening through which the gas flow can be discharged from the interior space. Furthermore, the heat storage device comprises a heater chamber in which a heating system is arranged, through which the gas flow can flow, wherein the heater chamber is connected to the storage chamber for the heat storage medium via an open volume of the interior space. Both the heater chamber and the storage chamber are located in the container.

[0048] In the heat storage device according to the invention, the heating system, by means of which a gas stream can be heated, and the heat storage medium, by means of which thermal energy can be stored, are arranged in different regions of the interior of the container. An open volume is formed between the heating system and the heat storage medium, or above these two units, through which the gas stream heated by the heating system can flow to the heat storage medium. The open volume is a gas distribution chamber of the heat storage device, which ensures that the gas heated by the heating system flows evenly through the entire cross-section of the heat storage medium and transfers heat to it.

[0049] The heat storage device according to the invention can be used to efficiently store excess electrical energy from highly fluctuating renewable sources, such as wind turbines or photovoltaic systems, or from other connected power grids, in the form of heat at a high temperature level. This can stabilize the relevant power grid. The heat stored in the heat storage medium of the heat storage device can be converted into electrical power at a later time, if required, for example, by a steam process, an Organic Rankine Cycle (ORC), or the like, or it can be transferred to another process (industrial heat supply, drying, etc.).In addition, the heat storage device can be used to continuously convert electrical energy into heat at a high temperature level for a downstream process, regardless of the loading state of the heat storage medium, for example to supply industry with heat.

[0050] Basically, the heat storage device according to the invention represents a storage device for thermal energy, which can release the energy in the form of heat to a gas stream at the same time or with a time delay compared to the converted electrical energy.

[0051] Since the heating system is arranged in the tank without additional housing and thermal insulation, the thermal inertia of the entire system can be minimized.

[0052] Furthermore, the heater chamber, which is designed in particular as a heating channel and in which the electrical heating system is arranged, forms a thermosiphon which allows a thermally advantageous arrangement of any required shut-off and throttling devices at a location of the heat storage device where low temperatures prevail, and which, due to its arrangement in the container, hardly generates any additional heat losses compared to an external thermosiphon.

[0053] In an advantageous embodiment of the heat storage device according to the invention, the heater chamber, in which the electrical heating system is arranged, is separated from the receiving chamber for the heat storage medium by a partition wall. The heater chamber is thus arranged in a defined area of ​​the interior of the container.

[0054] To ensure that the gas stream can flow through the heat storage medium efficiently, in a preferred embodiment of the heat storage device according to the invention, it is arranged on a support structure. For example, the support structure is a grid structure that is fixed to the walls of the container or mounted on a floor of the container like a table.

[0055] To facilitate the outflow of the gas stream after charging the heat storage medium, a distribution chamber is arranged beneath the support structure, which is connected to a warm air opening in the container. In particular, the warm air opening is the second opening in the container.

[0056] A particularly efficient charging and discharging process can be achieved if the heat storage device according to the invention additionally has a discharge opening arranged above the heat storage medium. For example, the heat storage device is discharged by introducing a warm gas stream and / or ambient air (in an open system) through a warm air opening and passing it through the heat storage medium. The warm gas stream is heated therein and then discharged from the heat storage device as a hot air stream through the discharge opening.

[0057] In a specific embodiment of the heat storage device according to the invention, the heat storage medium comprises shaped bricks through which the gas flow can flow and which preferably form a wall structure. For example, the shaped bricks each have a honeycomb structure with vertical channels, each of which has a square or hexagonal cross-section.

[0058] In an alternative embodiment, it is also conceivable that the heat storage means comprises, in addition to the shaped stones or instead of the shaped stones, a fill or the like made of a suitable material.

[0059] In order to be able to replace or maintain the heating system, the heat storage device according to the invention has a maintenance opening which is closed by means of a removable wall element.

[0060] The maintenance opening of the heat storage device preferably leads directly into the heating duct in which the electrical heating system is arranged.

[0061] The heating duct in which the electric heating system is arranged preferably has an at least largely rectangular cross-section. The electric heating system can be easily fitted into this cross-section.

[0062] A particularly efficient distribution of the gas flow over the cross section of the heat storage medium can be achieved if the heater chamber in which the electric heating system is arranged has an outlet opening arranged at the level of an upper side of the heat storage medium, wherein the open volume of the interior is located above the heat storage medium.

[0063] In a preferred embodiment of the heat storage device according to the invention, the electrical heating system arranged in the heater chamber comprises a resistance heater, and in particular a heating system configured according to the above-described heating system with a bearing element and heating unit. Thus, the heating system can be configured in the manner of a stack heater.

[0064] The invention also relates to a heat storage system comprising a heat storage device of the type described above and a conduit arrangement connected to the heat storage device. The conduit arrangement can lead to a consumer to which the heat stored in the heat storage device can be supplied in the form of hot air via the conduit arrangement. For example, the consumer is a heat exchanger (e.g., a steam generator) of a power plant, so that electricity can be generated using the heat stored in the heat storage device by means of a turbine and a generator.

[0065] In order to be able to guide the gas flow through the heat storage device, the heat storage system preferably has a fan which is adjustable, in particular with regard to speed, and which is arranged in the line arrangement.

[0066] Furthermore, the conduit arrangement preferably comprises a charging circuit connected to two openings of the heat storage device, so that warm air can be introduced through one opening. In the heat storage device, the warm air is heated in the heating system and then, after flowing through the open volume of the interior, is discharged into the heat storage medium, where it can then flow out of the heat storage device again as warm air through the second opening.

[0067] Preferably, the conduit arrangement comprises valves and / or flaps for controlling the gas flow through the heat storage device.

[0068] Further advantages and advantageous embodiments of the subject matter of the invention can be found in the description, the drawings and the patent claims.

[0069] Embodiments of the subject matter of the invention are shown schematically in simplified form in the drawing and are explained in more detail in the following description. It shows: Figure 1 shows a schematic, perspective sectional view of a heat storage device; Figure 2 shows the section according to Figure 1 in a plan view; Figure 3 a section through the heat storage device along the line III-III in Figure 2 ; Figure 4 a perspective sectional view of an alternative embodiment of a heat storage device; Figure 5 the section according to Figure 4 in a plan view; Figure 6 a section through the heat storage device according to Figure 5 along the line VI-VI in Figure 5 ; Figure 7 a heating system of the heat storage devices according to the Figures 1 to 6 ; Figure 8 a perspective view of a variant of a mounting matrix of the heating system; Figure 9 a heating unit of the heating system according to Figure 7; Figure 10 a plan view of a variant of a heating device of a heating unit of the Figure 9 shown type; Figure 11 an enlarged view of area XI in Figure 10 ; Figure 12 an enlarged view of area XII in Figure 9 ; Figure 13 shows a section through an alternative embodiment of a heat storage device in a loading operation; Figure 14 shows a discharging operation of the heat storage device according to Figure 13 ; Figure 15 shows a heating operation without storage process of the heat storage device according to Figure 13 ; Figure 16 shows a heating operation with loading process of the heat storage device according to Figure 13 ; Figure 17 shows a heating operation with simultaneous discharge process of the heat storage device according to Figure 13 ; Figure 18 a schematic structure of a heat storage system with a consumer in loading mode; Figure 19 the heat storage system according to Figure 18 in a discharge mode; and Figure 20 the heat storage system according to Figure 18in a heating mode.

[0070] In the Figures 1 to 3A heat storage device 1 is shown which can be used to efficiently store excess electrical energy from highly fluctuating renewable sources, for example from wind turbines or photovoltaic systems, or from connected power grids in the form of heat at a high temperature level, thus stabilizing the power grid. The stored heat can be converted into electrical power at a later time as needed by a water-steam process, an ORC process, or the like, or it can be released for other industrial or utility-related processes indirectly in the form of water vapor or directly in the form of a hot gas. In addition, the heat storage device 1 can generate hot air at a high temperature level using electrical energy, which can be used, for example, in connected power plants or industrial processes.

[0071] The heat storage device 1 comprises a container 2 which is cuboid in the broadest sense and in which an interior space 3 is formed which extends in the vertical direction between a container ceiling 4 and a container bottom 5 and in the transverse directions between four side walls 6.

[0072] The container 2 is provided with a loading opening 7 on a side wall 6 close to the container bottom 5, with an inlet / outlet opening 8 on another side wall 6 close to the container bottom 5, and with a discharge opening 9 on this side wall 6 adjacent to the container ceiling 4. The loading opening 7, the inlet / outlet opening 8, and the discharge opening 9 can be connected to lines of a piping system.

[0073] Furthermore, on the side wall 6, on which the loading opening 7 is formed, a maintenance opening 10 is formed in a central region in the vertical direction, which can be closed in a gas-tight manner by means of a detachable wall element 11.

[0074] On the inside, the side walls 6, the container ceiling 4 and the container bottom 5 are each provided with high-temperature-resistant insulation layers 12.

[0075] The interior space 3 of the container 2 has essentially cuboid dimensions. Furthermore, a partition wall 13 with a substantially U-shaped cross-section is formed in the interior space 3. The partition wall 13 stands on the container bottom 5 and has a vertical orientation. The short sides of the partition wall 13 border the side wall 6, on which the maintenance opening 10 is formed.

[0076] At a distance from the container bottom 5 and above the loading opening 7 and the inlet / outlet opening 8, the interior 3 is spanned by a grid structure 14, which has a horizontal orientation and is attached to the side walls 6 and the partition wall 13 and / or stands on the container bottom 5 via feet 22. The grid structure 14 forms a support structure or support construction.

[0077] The partition wall 13 separates a storage chamber 15 from a heater chamber 16 of the interior space 3. The storage chamber 15 accommodates a heat storage medium 17, which consists of stacked ceramic molded blocks 18, each having a square base and a honeycomb structure, the honeycombs of which form flow channels extending in the vertical direction or vertical direction of the heat storage device 1.

[0078] In an alternative embodiment, the heat storage means 17 can also be formed from a fill or the like.

[0079] The shaped blocks 18 extend from the grid structure 14 to close to the upper edge of the partition wall 13 and encompass, as Figure 3 can be seen, the partition wall 13 on its three sides.

[0080] The heater chamber 16 forms a heating channel, which is bounded at the bottom by the grid structure 14 and on which a stack of shaped blocks 19 is arranged as a support structure. Each of these blocks also has a honeycomb structure and corresponds to the shaped blocks 18 arranged in the storage chamber 15. The stack of shaped blocks 19 has a height that is less than that of the shaped blocks 18 in the storage chamber 15. A heating arrangement 20 is arranged on the shaped blocks 19. This heating arrangement represents an electrical heating device and is connected via connections 21 to a power source, for example, to a wind turbine, a photovoltaic system, and / or the power grid. An upper side of the heating arrangement 20 is approximately aligned with the upper side of the heat storage medium 17 in the storage chamber 15.

[0081] As already mentioned above, the maintenance opening 10 can be closed by means of a removable wall element 11. The wall element 11 has an insulation plug on the inside.

[0082] The storage space 15 and the heater space 16 are connected to each other via an open volume 24 of the interior space 3, which is arranged above the heater space 16 provided with the heating system or above the storage space 15 filled by the heat storage medium 17 and forms a gas distribution space.

[0083] Below the heater chamber 16, i.e., below the grid structure 14, there is a gas distribution chamber 24 through which gas can flow from the loading opening 7 into the heater chamber 16. Below the storage chamber 15, in which the heat storage medium 17 is arranged, there is a gas distribution chamber 25, which is connected to the inlet / outlet opening 8.

[0084] In the Figures 4 to 6 a heat storage device 1' is shown, which represents an alternative embodiment and largely corresponds to that according to the Figures 1 to 3corresponds, but differs from it in that the container 2 comprises a side wall 6' on the side of the maintenance opening 10, which has an outwardly offset projection 23. This makes it possible for a partition wall 13', which separates a heater chamber 16 from a storage chamber 15 of the interior 3, to be aligned with the inside of the side wall 6'.

[0085] Furthermore, the heat storage device 1' corresponds to the heat storage device according to the Figures 1 to 3 trained, so reference is made to the relevant description.

[0086] In Figure 7The heating arrangement 20 of the heating system arranged in the heater chamber 16 of the heat storage devices described above is shown in isolation. The heating arrangement 20 is provided on the bottom side with two rows of six shaped blocks 26 arranged one behind the other, which form a support structure and each have a honeycomb structure, with channels formed by the honeycombs through which air can flow in a vertical direction. The shaped blocks 26 are ceramic shaped blocks made from cordierite. Arranged on the shaped blocks 26, which have a substantially inverted U-shaped cross-section and are provided at the bottom with a perforated plate 261 representing a static throttle element, are several layers 27, each of which is formed from, in the present case, six heating units 28 arranged side by side.On the upper side, the heating arrangement 20 is defined by a layer of adjacently arranged shaped blocks 30 forming a cover 29. These shaped blocks also have a honeycomb structure and the channels formed by the honeycombs are vertically aligned and allow flow. Furthermore, the heating arrangement 20 comprises two connection contacts 31 and 32, which are connected to a power source or a power grid.

[0087] The heating units 28 are basically composed of identical parts and each comprise two bearing elements 33 and a heating device 34. The bearing elements 33 are each formed from a ceramic molded block made from cordierite and having a honeycomb structure. The individual honeycombs of the bearing elements 33 each form a channel extending in the vertical direction and each have a square footprint. Furthermore, the bearing elements 33 each have a substantially U-shaped cross-section, so that a base plate 35 and two side walls 36 are formed, which delimit a receiving space for the precise accommodation of the heating device 34. On the underside, the base plates 35 of the bearing elements 33 each have, in the region of the lateral edges, a recess 37 with a rectangular cross-section, into which the upper side of the corresponding side wall 36 of the underlying bearing element 33 engages when stacked.This ensures a precise positioning of the stacked bearing elements 33. The upper ribs of the shaped blocks 26 engage in the recesses 37 of the lowermost layer of heating units 28.

[0088] At the Figure 9 In the variant shown, the side walls 36 and the base plate 35 of a bearing element 33 are made in one piece. Figure 8 In the variant shown, the side walls 36 are separate components, each mounted on a base plate. Furthermore, adjacent bearing elements each share a side wall, meaning this side wall overlaps adjacent base plates 35.

[0089] In order to prevent a flow through the side walls 36 and thus a bypass gas flow, the side walls 36 are provided on their upper side with a seal 38, which consists for example of a ceramic paper (cf. Fig. 8 ).

[0090] The heating devices 34 of the heating units 28 are essentially identical in construction and each have an inflow base area, which in the present case corresponds to the area between the side walls 36 of two successively arranged bearing elements 33. In the installed position, the heating device 34 rests on the base plates 35 of these two bearing elements 33. As can be seen in particular from the Figures 9 to 11As can be seen, the heating devices 34 each comprise six heating plate units 39A, 39B, 39C, 39D, 39E and 39F, which are connected in series. For this purpose, the heating plate units 39A and 39B, the heating plate units 39B and 39C, the heating plate units 39C and 39D, the heating plate units 39D and 39E and the heating plate units 39E and 39F are each connected to one another via a contact plate 40, which is arranged on a respective end face of the heating device 34. A partition 41 is arranged between each adjacent heating plate unit, which partition is made of an electrically insulating material, for example a ceramic material, and also ensures electrical insulation between each adjacent contact plate 40. Furthermore, the heating device 34 comprises side walls 42 which, in the installed position, border on or rest against the respective side walls 36 of the respective two bearing elements 33.For electrical contacting, the heating device 34 has a first connection element 43 and a second connection element 44, wherein the connection elements 43 and 44 are each formed from a sheet metal part that is aligned with the contact plates 40 arranged on the respective end face of the heating device 34. The connection element 43 is electrically connected to an end face of the heating plate unit 39A, whereas the connection element 44 is electrically connected to an end face of the heating plate unit 39F.

[0091] The individual heating plate units 39A, 39B, 39C, 39D, 39E and 39F each comprise a plurality of heating plate strips 45 and 46.

[0092] At the Figure 11In the embodiment shown, corrugated heating plate strips 45 and flat heating plate strips 46 are arranged alternately one behind the other in the stacking direction, with the corrugated heating plate strips 45 being supported by their corrugation crests on the adjacent flat heating plate strips 46. The outer corrugated heating plate strips 45 are also supported on the respective partition wall 41 or the respective side wall 42.

[0093] In their end regions, the heating plate strips 45 and 46 are aligned parallel to one another and are each connected to one another via a spacer structure 47, which also establishes contact between the respective heating plate stack and the connection element 43 or 44, or the respective contact plate 40. The spacer structure 47 comprises shim plates 48 designed as spacer elements, which are arranged between the parallel end regions of adjacent heating plate strips and are welded or soldered to them. The shim plates 48 each have a thickness that corresponds to the amplitude of the corrugation of the corrugated heating plate strips 45.

[0094] The corrugation of the heating plate strips 45 forms a honeycomb structure which provides a large inflow area for the gas flow flowing through the heating device 34.

[0095] In an alternative embodiment, several shims can be arranged between adjacent heating plate strips. It is also conceivable for the spacer structure to be formed from a comb structure into which the end regions of the heating plate strips are inserted.

[0096] Furthermore, it is pointed out that in the Figures 9 and 12 In the variant shown, only corrugated heating plate strips are provided in the heating plate stacks, which are connected to one another in their two end regions via a conductive spacer structure made of lining plates or the like.

[0097] In principle, it is conceivable for the heating devices of the heating units in the various layers 27 of the heating arrangement 20 to have different heights and / or different honeycomb channel shapes. In the presently illustrated embodiment, the heating devices 34 of a layer 27 of the heating arrangement 20 are connected in series via contact plates 49. It is, of course, also conceivable to connect them in parallel. Furthermore, in the present embodiment, successive layers are connected in parallel pairs via contact strips 50. In principle, the interconnection of the heating devices 34 can be freely selected as required.

[0098] In order to be able to determine the temperature of the gas stream heated by the heating arrangement 20, a thermocouple 51 is arranged in the cover 29 in a transverse bore of a shaped block 30.

[0099] In the Figures 13 to 17a heat storage device 60 is shown, which largely corresponds to that according to the Figures 1 to 3 , but differs from it in that it does not include a stack heater of the type described above in the heater chamber 16, which forms a heating channel. Rather, resistance heating elements 61, which are formed from heating coils or the like and are connected to a power grid via a connection area 62, engage in the heater chamber 16. Otherwise, the heat storage device 60 corresponds to that according to the Figures 1 to 3 , which is why reference is made to the relevant description.

[0100] Corresponding to the heat storage devices 1 and 1', the heat storage device 60 can be switched to a loading mode by means of corresponding valves, in which a gas stream consisting of warm air is introduced via a loading opening 7. This gas stream is, as Figure 13As can be seen, the gas stream is guided from bottom to top in the heater chamber 16 and heated by means of the resistance heating elements 61 and passed through the gas distribution chamber 24, which forms an open volume, through the heat storage medium 17, which is constructed from the shaped blocks 19. The shaped blocks 19 are thereby charged, i.e., heated. The gas stream, which has then cooled again, is discharged from the heat storage device 60 via the gas distribution chamber 25 and the inlet / outlet opening 8.

[0101] In a Figure 14In the discharge operation shown, a gas stream consisting of warm air is introduced into the heat storage device via the inlet / outlet opening 8 and is then passed from bottom to top through the gas distribution chamber 25 through the heat storage medium 17 formed from the shaped blocks 19, where it is heated. After heating, the heated gas stream is discharged from the heat storage device via the upper gas distribution chamber 24 and the discharge opening 9 for further use.

[0102] In Figure 15 A heating operation without heat storage is shown for the heat storage device 60. In this operation, a warm air gas stream is introduced into the heat storage device via the loading opening 7 and heated in the heater chamber 16 by means of the resistance heating elements 61. It is then discharged from the heat storage device 60 as a hot air gas stream via the upper gas distribution chamber 24 and the discharge opening 9.

[0103] According to Figure 16The described heat storage device 60 can also be operated in such a way that a warm air gas stream is introduced into the heat storage device via the loading opening 7 and heated by means of the resistance heating elements 61. The resulting hot air gas stream is divided in the upper gas distribution chamber 24 and, on the one hand, discharged from the heat storage device 60 via the discharge opening 9 and, on the other hand, is passed through the heat storage medium 17 formed from the shaped blocks 19 to charge it and is then discharged from the heat storage device via the lower gas distribution chamber 25 and the inlet / outlet opening 8.

[0104] In another, in Figure 17In the operating mode shown, the heat storage device 60 can be operated such that a warm air gas stream is introduced via the loading opening 7 and the inlet / outlet opening 8. The gas stream introduced via the loading opening 7 is guided vertically upwards in the heater chamber 16 and heated by means of the resistance heating elements 61 and discharged via the upper gas distribution chamber 24 and the discharge opening 9. The warm air gas stream introduced via the inlet / outlet opening 8 is guided through the loaded heat storage medium 17 and heated there by heat exchange, before being subsequently discharged from the heat storage device via the upper gas distribution chamber 24 and the discharge opening 9.

[0105] The above-mentioned operating modes are of course also possible using the heat storage devices according to the Figures 1 to 6 feasible.

[0106] In the Figures 18 to 20a heat storage system 70 is shown which has a heat storage device 71 which can be configured either according to the Figures 1 to 6 illustrated embodiments or according to the Figures 12 to 17illustrated embodiment. In addition, the heat storage system 70 comprises a line arrangement 72 which is connected to a consumer 73, which can be designed, for example, as a steam generator of a power plant. The line arrangement 72 comprises a line 74 which connects the discharge opening 9 of the heat storage device 71 to an inlet 75 of the consumer 73. The loading opening 7 of the heat storage device 71 is connected to a line 76 of the line arrangement 72, and the inlet / outlet opening 8 of the heat storage device 71 is connected to a line 77 of the line arrangement 72. An outlet 78 of the consumer 73 is connected to a line 79 which leads to a fan 80, which in turn is connected via the line 76 to the loading opening 7 of the heat storage device 71. Downstream of the fan 80, a branch line 81 branches off from the line 76 and is connected to the line 77.Upstream of the blower 80, a branch line 82 branches off from the line 79, which is also connected to the line 77.

[0107] In order to switch the heat storage system 70 to different operating modes, a valve 83 is arranged in line 76, a valve 84 is arranged in branch line 81, a valve 85 is arranged in branch line 82, and a valve 86 is arranged in line 79 upstream of the branch of branch line 82. Instead of the valves or in addition to them, other suitable shut-off valves, such as flaps or the like, can of course also be used.

[0108] Furthermore, the heat storage device 71 is connected to a power source 87, which can be formed by the power grid or a photovoltaic system or even a wind turbine and is provided with a switch 88. In a loading mode, in which electrical energy is converted into heat and the heat is to be stored in the heat storage medium 17 of the heat storage device 71, a warm air gas stream is introduced from below into the heater chamber 16 of the heat storage device 71 via the loading opening 7 by means of the fan 80 with the valve 83 open. The switch 88 is closed, so that the heater arrangement is operated and the gas stream is heated in the heater chamber 16. The heated gas stream is guided via the upper gas distribution chamber 24 into the storage chamber 15 and passed from top to bottom through the heat storage bed formed by the heat storage medium 17, whereby the heat is released to the heat storage bed and stored there.Subsequently, a warm air gas stream is discharged from the heat storage device 71 via the inlet / outlet opening 8 and guided to the blower 80 via the line 77 and the branch line 82, where it can then be fed back to the heat storage device 71 in the manner described above. The valves 84 and 86 are closed in this charging mode.

[0109] In a Figure 19In the discharge mode shown, valves 84 and 86 are opened and valves 83 and 85 are closed. By means of the fan 80, warm air is then introduced into the heat storage device 71 from below via the branch line 81 and the line 77 and the inlet / outlet opening 8 and heated in the storage bed formed by the heat storage medium 17. The resulting hot air gas stream is discharged from the top of the heat storage device 71 via the discharge opening 9 and made available to the consumer 73 via the line 74. This consumer, in turn, releases warm air, which can be fed back to the heat storage device 71 by means of the fan 80 in the manner described above.

[0110] In a Figure 20In the pure heating operation shown, valves 84 and 85 are closed, whereas valves 83 and 86 are open. By means of the fan 80, warm air can then be introduced into the heater chamber 16 of the heat storage device 71 and heated there. The resulting hot air gas stream is led out of the heat storage device 71 via the discharge opening 9 and then fed to the consumer 73 via the line 74. The consumer 73 in turn emits a warm air gas stream, which is led via the line 79 to the fan 80 and can be fed back into the heat storage device 71 in the manner described above.

[0111] An embodiment of a heat storage system (not shown in detail) can be designed as an at least partially open system, in which the air exiting the consumer is released entirely or partially into the environment. A corresponding amount of ambient air is then drawn in on the intake side of the fan when the heat storage device is discharged. Otherwise, this embodiment can correspond to the embodiment described above. List of reference symbols

[0112] 1, 1'Heat storage device 2Vessel 3Interior 4Vessel ceiling 5Vessel floor 6Side walls 7Loading opening 8Inlet / outlet opening 9Discharge opening 10Maintenance opening 11Wall element 12Insulating layer 13, 13'Partition wall 14Grid structure 15Storage space 16Heater space 17Heat storage medium 18Shaped blocks 19Shaped blocks 20Heating arrangement 21Connections 22Feet 23Approach 24Gas distribution space 25Gas distribution space 26Shaped block 27Layers 28Heating unit 29Cover 30Shaped blocks 31Connection contact 32Connection contact 33Bearing element 34Heating device 35Base plate 36Side walls 37Recess 38Sealing 39A, B, C, D, E,FHeating plate unit 40Contact plate 41Partition wall 42Side wall 43Connection element 44Connection element 45Heating plate strip 46Heating plate strip 47Spacer structure 48Lining plate 49Contact plate 50Contact strip 51Thermocouple 60Heat storage device 61Resistance heating elements 62Connection area 70Heat storage system 71Heat storage device 72Pipe arrangement 73Consumer 74Pipe 75Inlet 76Pipe 77Pipe 78Outlet 79Pipe 80Fan 81Branch line 82Branch line 83Valve 84Valve 85Valve 86Valve 87Power source 88Switch 261Perforated plate,

Claims

1. A heat-storage device, comprising a container (2) having an interior space (3), which has a storage space (15) in which a heat-storage medium (17) for storing thermal energy is disposed, the container (2) having a first opening (7) via which a gas stream is conducted into the interior space and a second opening (8) via which the gas stream is conducted from the interior space (3), the heat-storage device having a heater space (16) in which an electric heating system is disposed through which the gas stream flows, the heater space (16) being connected to the storage space (15) for the heat-storage medium (17) via an open volume of the interior space (3), characterized in that the open volume is disposed above the heater space (16) connected to the heating system and above the storage space (15) filled by the heat-storage medium (17) and forms a gas distribution space, a maintenance opening (10) being provided which is closed by means of a detachable wall element (11).

2. The heat-storage device according to claim 1, characterized in that the heater space (16) is disposed in the interior space (3) of the container (2) and is separated from the storage space (15) for the heat-storage medium (17) by means of a divider wall (13, 13').

3. The heat-storage device according to claim 1 or 2, characterized in that the heat-storage medium (17) is disposed on a carrier structure.

4. The heat-storage device according to claim 3, characterized in that the carrier structure comprises a grid structure (14).

5. The heat-storage device according to claim 3 or 4, characterized in that a gas distribution space (25), which is connected to an opening (8) of the container (2), is disposed below the carrier structure.

6. The heat-storage device according to claim 5, characterized in that the opening (8) is a second opening.

7. The heat-storage device according to any one of the claims 1 to 6, characterized by a discharge opening (9) disposed above the heat-storage medium (17).

8. The heat-storage device according to any one of the claims 1 to 7, characterized in that the heat-storage medium (17) comprises molded bricks (18), through which the gas stream flows and which preferably are disposed in the manner of a masonry bond.

9. The heat-storage device according to any one of the claims 1 to 8, characterized in that the heater space (16) has at least one mostly rectangular cross section.

10. The heat-storage device according to any one of the claims 1 to 9, characterized in that the heater space (16) has an exit opening disposed at the level of an upper side of the heat-storage medium (17), the open volume of the interior space (3) being located above the heat-storage medium (17).

11. The heat-storage device according to any one of the claims 1 to 10, characterized in that the heating system comprises a resistance heater (61).

12. The heat-storage device according to any one of the claims 1 to 11, characterized in that a gas distribution space is disposed below the heating system and downstream of the first opening (7).

13. The heat-storage device according to any one of the claims 1 to 12, characterized in that the heating system comprises an inlet side and an outlet side and a heating arrangement (20), which comprises at least one heating unit (28), which comprises a heating device (34) having an inflow base area, which is perpendicular to the gas stream, and at least one mounting element (33), on which the heating device (34) is disposed and which is permeable to the gas stream so that the gas stream can flow onto the inflow base area of the heating device (34) or the gas stream can flow from the heating device (34) through the mounting element (33).

14. A heat-storage system, comprising a heat-storage device (1, 1', 60) according to any one of the claims 1 to 13 and a pipe arrangement (72) connected to the heat-storage device (1, 1', 60).

15. The heat-storage system according to claim 13 or 14, characterized in that the pipe arrangement (72) comprises a charging circuit connected to two openings (7, 8) of the heat-storage device (71).