Tank

Abstract

The invention relates to a tank (1) having a storage volume (2) and comprising a base plate (3) and at least two first planar side wall elements (5) and at least two second planar side wall elements (6), with at least the side wall elements (5, 6) being manufactured at least in part from ultra-high-strength concrete. The aim of the invention is to obtain a modular tank (1) which is inexpensive to produce, can be transported to its intended location with relatively low transportation costs and can be put into operation easily. This aim is achieved in that: the storage volume (2) is lined with a sealing film made of plastic; the side wall elements (5, 6) have base-plate connecting portions (7a, 7b) which, during operation, are inserted interlockingly into receiving portions (4a, 4b) in the base plate (3); the side wall elements (5, 6) each have side-edge closure portions (8a, 8b); and, during operation, one second side-edge closure portion (8b) of each second side wall element (6) engages interlockingly in a first side-edge closure portion (8a) of an adjoining first side wall element (5) in such a way that self-locking or self-clamping connections are established.

Description

[0001] TANK

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a tank, in particular a concrete tank, for storing liquids, wherein the tank comprises a base plate having a center point and at least two first plate-shaped side wall elements and at least two second plate-shaped side wall elements, wherein the base plate together with the side wall elements delimits a storage volume of the tank in an operating state, wherein at least the side wall elements are at least partially made of ultra-high-strength concrete.

[0004] Ultra-high-performance concrete (UHPC), also known as ultra-high performance concrete, is generally understood to be a concrete mixture which is characterised by comparatively high tensile and compressive strength as well as high density. These properties are generally achieved by a small grain size of the aggregate (e.g. rock) compared to normal concrete, for example less than 1 to 2 mm, and a reduced water content compared to normal concrete, for example to a w / c ratio (water-cement ratio) of 0.3 to 0.2.Ultra-high-performance concrete can be achieved, for example, through granulometric optimization of the fines used as aggregate for the cement paste matrix. These fines are typically materials with grain sizes in the single-digit micrometer range or in the nanometer range, such as silicate dust, aluminosilicates, or metakaolin. The addition of superplasticizers, such as high-performance superplasticizers based on polycarboxylate ethers, is generally required to achieve flowability and self-compacting capacity. One possible approach to distinguishing ultra-high-performance concrete from standard concrete would be a compressive strength of over 150 N / mm². 2 and a w / c ratio < STATE OF THE ART

[0005] Tanks, particularly concrete tanks, are typically used to store or keep liquids in their storage volume for a specific period of time, for example weeks, months, or years. Accordingly, a tank must be liquid-tight to prevent unwanted leakage of the stored liquid. One application is often to store water, although this storage function is not necessarily the primary function. For example, swimming pools, fish farms, buffer tanks, and stratified storage tanks are also tanks within the meaning of the above definition.

[0006] The construction of a tank must be so robust that, on the one hand, the hydrostatic pressure forces exerted on the inner walls by the stored liquid and, on the other hand, any external forces do not cause damage to the tank or impair its tightness.

[0007] There are two typical designs for such tanks: On the one hand, tanks can be designed to be free-standing, with the base plate usually being at ground level; on the other hand, tanks can be designed as tanks sunk into the ground, with the base plate and at least a section of the side wall elements, preferably substantially the entire storage volume, being below ground level.

[0008] A conventional manufacturing process for concrete tanks is to strip the formwork and pour the concrete on site, which is costly and logistically complex, particularly when using ultra-high-performance concrete. Alternatively, the concrete tank can be prefabricated as a whole, although this significantly increases the problem of high transport costs. Another option for concrete tanks is to manufacture modular concrete rings. These are delivered to the installation site and assembled on site to form a concrete tank before being brought into operation - also known as the ready-to-use state. For this design, too, the effort required to transport and assemble the tank is relatively high, particularly due to the large amount of space required by concrete rings for road transport.

[0009] Another problem with the current state of the art relates to ensuring the tank's tightness. Plastic-based sealing systems, such as those based on PVC, rubber, or polyurethane, are generally known for lining the interior surfaces of the storage volume. However, sealing the connecting areas between individual modules is challenging, especially in modular systems.

[0010] EP 2730722A1 discloses a tank designed as a liquid-tight basin, which is composed of prefabricated segments in a modular design, wherein the segments are made of high-performance concrete or ultra-high-strength concrete. A single segment comprises a section of the base plate and at least two side wall elements. The segments are assembled on site, with recesses provided at the connecting areas into which adhesive tabs are inserted, which are then glued to seal the basin.

[0011] CN217001128U shows a water storage tank made of plate-shaped concrete elements, with the corner connections made of metal screws and dowels. Furthermore, the side wall elements are bolted to the base plate using vertical steel rods, and the side wall elements are prestressed by integrated horizontal steel rods. OBJECT OF THE INVENTION

[0012] It is therefore an object of the invention to overcome the disadvantages of the prior art and to propose a modular tank, in particular a concrete tank, which, on the one hand, can be manufactured cost-effectively, transported to its destination with relatively low costs, and put into operation in a simple manner. On the other hand, the tank should be characterized by excellent stability and tightness throughout its service life, which typically extends over many years.

[0013] PRESENTATION OF THE INVENTION

[0014] This object is achieved in a tank according to the invention of the type mentioned at the outset in that the storage volume is lined by means of a sealing film made of plastic, the first side wall elements have first base plate connecting sections which, in the operating state, are inserted in a form-fitting manner into first receiving sections of the base plate, the second side wall elements have second base plate connecting sections which, in the operating state, are inserted in a form-fitting manner into second receiving sections of the base plate, the first side wall elements each have two first side edge closure sections, the second side wall elements each have two second side edge closure sections, and that, in the operating state, a second side edge closure section of a second side wall element engages in a form-fitting manner into a first side edge closure section of an adjacent first side wall element,that a compressive force exerted on the side wall elements by a liquid in the storage volume reinforces a clamping force acting reciprocally between the interlocking first side edge closure sections and second side edge closure sections. The present invention is based on several aspects, in particular on the modular construction in combination with the use of ultra-high-strength concrete, on the creation of a seal by means of a sealing film, and on the special connection between the side wall elements and the floor slab, whereby the desired effects can only be achieved as a whole, as will be explained below.

[0015] The modular design of the tank, which is composed of plate-shaped side wall elements and a base plate, allows for cost-effective production and low transport costs, as the individual elements allow space-saving transport and a high packing density. If the dimensions of the side wall elements are selected accordingly, for example based on the size of a transport container or a standard truck, they can be transported using normal transport methods, in particular by road, rail or air. The same applies to the base plate, although it is fundamentally also conceivable to cast the base plate in concrete on site, as the formwork effort is significantly lower here than for the side wall elements.Preferably, the tank may accordingly have a dimension in the height direction of 2.5 m, a dimension in the width direction of 2.5 m and a dimension in the length direction of between 4 m and 12 m.

[0016] The use of ultra-high-performance concrete also enables the side wall elements to be thin-walled. Due to the material properties, this allows them to be flexible, for example to compensate for movements in the ground. At the same time, the thin-walled design of the side wall elements reduces the transport weight, which further cuts transport costs. While conventional concrete side walls for tanks are usually between 8 and 15 cm thick, a thin-walled design is understood to mean a thickness of less than 8 cm, preferably less than 5 cm, with the minimum thickness being between 1 cm and 3 cm.

[0017] Due to the geometry of the side edge closure sections, in the operating state, each first side wall element is received between two second side wall elements, wherein one first side edge closure section of the first side wall element engages with one of the second side edge closure sections of the one second side wall element and the other first side edge closure section of the first side wall element engages with one of the second side edge closure sections of the other second side wall element. Analogously, each second side wall element is also received between two first side wall elements.

[0018] By providing the sealing film made of plastic, the function of sealing against liquid leakage from the tank is decoupled from the mechanical stability of the tank. The sealing film can, for example, be a film made of polypropylene or polycarbonate and have a thickness of between 0.2 mm and 1 mm, preferably between 0.5 mm and 0.8 mm. The storage volume can be lined, for example, by laying out, rolling out, folding or inflating a prefabricated sealing film. The sealing film preferably consists of individual welded film elements which are dimensionally adapted to the dimensions of the storage volume so that the sealing film can be folded together before lining, in particular as a separate sack-like bundle.

[0019] Advantageously, the sealing film is not connected to the inner walls of the side wall elements, so that relative movements between the side wall elements and the sealing film are possible. This means, for example, movements of the side walls due to settlement in the ground or even cracks or breaks in the concrete can be compensated for without the tightness of the tank being affected. It can be provided that the sealing film is pulled over an upper edge of the side wall elements in order to fix the sealing film to the outside of the side wall elements. Alternatively, it can also be provided that the sealing film is fixed in an end region of the side wall elements facing away from the base plate or is clamped by an attached cover element or is fixed to an attached cover element.

[0020] Another important aspect is the positive connection between the side wall elements and the base plate as well as the positive connection at the side edges of the side wall elements, which connects the side wall elements to each other.

[0021] The positive connection between the first base plate connecting sections of the first side wall elements and the first receiving sections of the base plate, as well as the second base plate connecting sections of the first side wall elements and the first receiving sections, determines the positioning of the side wall elements relative to the base plate, and the positive connection further increases the stability of the tank. Another advantage is that the positive connection reduces the mobility of the side wall elements relative to the base plate by at least one translational degree of freedom in the operating state.

[0022] For example, the positive connection can be realized by appropriately shaped recesses in the base plate, which form the receiving sections, with suitable geometries, wherein the base plate connecting sections have a corresponding counter-geometry.

[0023] In the simplest design, the receiving sections are formed as rectangular recesses into which the lowest sections of the side wall elements are inserted as floor panel connecting sections. However, the wedge-shaped geometry of the receiving sections and the floor panel connecting sections, described below, is advantageous. The receiving sections can preferably also protrude vertically from an inner surface of the floor panel.

[0024] A further integral contribution to the stability of the tank is made by the self-locking side edge closure sections, which are designed in such a way that a compressive force acting inside the storage volume, in particular the hydrostatic pressure of the liquid, when the tank is filled, increases the clamping force between the respective side edge closure sections. This is achieved by the form-fitting side edge closure sections being designed in such a way that they are pressed against one another by the compressive force. Thus, when the tank is filled, the geometry of the side edge closure sections prevents the side edge closure sections from separating from one another and the tank from collapsing. In this context, they are also referred to as self-locking side edge closure sections.

[0025] The side edge closure sections can be designed, for example, according to the sheet pile wall principle, with a wedge-shaped geometry preferably being used, as described in detail below. Depending on the geometry, the side edge closure sections can be inserted into one another either along the height direction or, preferably, along the length or width direction to create the positive connection.

[0026] Due to the self-locking effect of the side edge closure sections, no additional mechanical connection, such as screw connections or adhesive connections, is required, without negatively affecting the mechanical stability of the tank. Advantageously, the side edge

[0027] Closure sections over the entire extension of the side wall elements in the vertical direction.

[0028] The main body of the tank preferably consists of a rectangular base plate and four side wall elements, namely two first side wall elements and two second side wall elements, so that the main body is designed as a prism with a rectangular base area. In principle, designs with any even number of corners are also conceivable, such as hexagons (three first and three second side wall elements) or octagons (four first and four second side wall elements), with substantially regular polygons or at least polygons with parallel, opposite sides being preferred.

[0029] In order to further increase the flexibility and resilience of the side wall elements on the one hand and to further improve the mechanical strength, particularly with regard to tensile and compressive stresses, on the other, one embodiment of the invention provides for the ultra-high-strength concrete to be fiber-reinforced, preferably having a multi-layer structure. By reinforcing the ultra-high-strength concrete with fibers, a composite material is produced which has advantageous properties. Glass fibers, plastic fibers or carbon fibers are particularly suitable as materials for the fiber reinforcement, although metal fibers are also conceivable. It should be noted that with metal fibers there is a certain risk of rust due to the ambient humidity.

[0030] It is advantageous if the fibers are in the form of mats, in particular fabric mats, or as a fabric. The use of such fabrics also allows a multi-layer structure of the fiber-reinforced concrete. Preferably, a fabric layer is incorporated between two concrete layers, with one, two or more than two fabric layers being conceivable. As mentioned above, the use of ultra-high-strength concrete, in particular fiber-reinforced, allows a thin-walled design of the side wall elements. Therefore, a further embodiment of the invention provides that the side wall elements are thin-walled and have a thickness of between 1 cm and 8 cm, preferably between 1.5 cm and 5 cm, in particular between 2 cm and 4 cm.

[0031] In order to make the self-locking side edge locking sections work simply, the first side wall elements are designed as outer wall elements and the second side wall elements as inner wall elements. During installation, the outer wall elements are placed first and then an inner wall element is pushed between two outer wall elements. The inner wall elements also prevent two opposing outer wall elements from being pushed against each other during operation and serve as locking elements. The outer wall elements have the side edge connecting sections on their inside, i.e. the side facing the center point, while the inner wall elements have the side edge connecting sections on their outside, i.e. the side facing away from the center point.When the side edge connecting portions of all side wall elements have been engaged by sliding them into their counterparts, each side wall element is locked at three edges - two side edges and one bottom edge.Accordingly, a further embodiment of the invention provides that the first side edge closure sections are arranged on a side of the first side wall elements facing the center point in order to form outer wall elements, and the second side edge closure sections are arranged on a side of the second side wall elements facing away from the center point in order to form inner wall elements, wherein in the operating state the second side edge closure sections of one of the second side wall elements designed as inner wall elements are pushed from the direction of the center point into the respective first side edge closure sections of the two adjacent first side wall elements designed as outer wall elements.

[0032] Even though it is fundamentally sufficient for the stability of the tank if the connection between the side wall elements and the base plate is positively locking, it is advantageous if this positively locking connection, like the side edge closure sections, is also designed to be self-clamping. In other words, the base plate connecting sections and the receiving sections are designed in such a way that a compressive force acting inside the storage volume, in particular the hydrostatic pressure of the liquid when the tank is filled, increases the clamping force between the base plate connecting sections and the receiving sections. This is achieved by the corresponding base plate connecting sections and receiving sections being designed in such a way that they are pressed against one another by the acting compressive force.In particular, in conjunction with the design of the side wall elements as inner wall elements and outer wall elements, the effect can be achieved by arranging the base plate connecting sections on an outer side, i.e. a side facing away from the center point, of the side wall elements. Accordingly, one embodiment of the invention provides that the base plate connecting sections are each arranged on a side of the side wall elements facing away from the center point, in order to increase a clamping force acting between the respective interlocking base plate connecting sections of the side wall elements and the receiving sections of the base plate by a compressive force exerted on the side wall elements by a liquid located in the storage volume.

[0033] As already mentioned above, the self-locking effect of the side edge closure sections can be realized particularly easily by means of a wedge-shaped geometry. Therefore, one embodiment variant of the invention provides that the side edge closure sections of the side wall elements are wedge-shaped, wherein the first side edge closure sections are designed as outer wedges, which outer wedges each form a wedge-shaped receiving volume with an inner surface of the respective first side wall element, and the second side edge closure sections are designed as inner wedges that can be inserted into the receiving volumes of the first side edge closure sections. In other words, the first side edge closure sections designed as outer wedges form a triangular-prismatic undercut into which the corresponding second side edge closure sections designed as inner wedges can be received.The wedge angle is preferably between 30 ° and 60 ° , in particular 45 ° + / - 5 ° , particularly preferably exactly 45 ° .

[0034] According to the same principle, the self-clamping effect of the positive connection between side wall elements and base plate can also be implemented particularly easily by means of a wedge-shaped geometry. Therefore, one embodiment of the invention provides that the base plate connecting sections of the side wall elements and the receiving sections of the base plate are wedge-shaped, wherein the receiving sections are designed as outer wedges, which outer wedges each form a wedge-shaped receiving volume with an inner surface of the base plate, and the base plate connecting sections are designed as inner wedges that can be inserted into the receiving volumes of the receiving sections. In other words, the receiving sections designed as outer wedges form a triangular-prismatic undercut into which the corresponding base plate connecting sections designed as inner wedges can be received.The wedge angle is preferably between 30 ° and 60 ° , in particular 45 ° + / - 5 ° , particularly preferably exactly 45 ° .

[0035] In order to reduce the weight and, in the case where the corresponding elements of the tank are made, in particular in one piece, from ultra-high-strength concrete, to reduce the material expenditure and material accumulation, a further design variant can provide for the side edge closure sections and / or the receiving sections and / or the base plate connecting sections to comprise an internal displacement body. The internal displacement body can be either hollow bodies such as pipes or shaped pipes or solid bodies with a lower density than concrete, preferably solid bodies made of thermal insulation material. The use of internal displacement bodies is particularly advantageous for wedge-shaped sections, in particular for sections designed as external wedges, in order to additionally reduce the load on the connection point.

[0036] In principle, it is conceivable that the side edge closure sections, the base plate connecting sections, and the base plate receiving sections are manufactured as separate elements and mounted to the side wall elements or the base plate. For example, these elements could be made of stainless steel.

[0037] However, it is advantageous if the side edge closure sections are an integral part of the side wall elements and / or that the base plate connecting sections are an integral part of the side wall elements, since material costs and manufacturing costs can be reduced if the side wall elements can be manufactured together with at least one of the sections.

[0038] According to one embodiment variant of the invention, it is therefore provided that the first side edge closure sections are formed integrally with the first side wall elements and / or that the second side edge closure sections are formed integrally with the second side wall elements.

[0039] According to a further embodiment of the invention, it is analogously provided that the first base plate connecting sections are formed integrally with the first side wall elements and the second base plate connecting sections are formed integrally with the second side wall elements.

[0040] In particular, if the first sidewall elements are formed integrally with the first side edge closure sections and the first floor panel connecting sections, ready-to-assemble sidewall elements can be manufactured, preferably by casting fiber-reinforced ultra-high-strength concrete or casting ultra-high-strength concrete into a mold in which corresponding fabric layers are arranged. The same applies analogously to the second sidewall elements.

[0041] To increase stability, the second side wall elements can be provided with two second side edge closure sections each merging into the second base plate connecting section at the lower end, thus forming a frame structure closed on three sides. The first side edge closure sections have a corresponding recess to allow them to be pushed together over the entire length of the side edge closure sections during operation.

[0042] Furthermore, the fabric reinforcement promotes the stability of the connection points where the side edge closure sections or the base plate connecting sections are connected to the plate-shaped base body of the side wall elements. It is particularly advantageous if the incorporated fabric mats also extend into the respective sections in order to ensure a stable connection in the connecting sections during operation, even under compressive loads.

[0043] The above statements also apply analogously to the receiving sections of the floor slab, so that according to a further embodiment of the invention, the first receiving sections and the second receiving sections are formed integrally with the floor slab. In detail, the floor slab can be made in one piece from, preferably fiber-reinforced, ultra-high-strength concrete, whereby insulation material can also be incorporated if necessary.

[0044] To increase stability, the base plate can also have a surrounding support frame which surrounds the first and second receiving sections on the outside in a frame-like manner.

[0045] The advantages described above also apply analogously to the fabric reinforcement of the receiving sections.

[0046] For the reasons stated above, a further embodiment of the invention provides that the first side wall elements and / or the second side wall elements and / or the base plate are made of ultra-high-strength, preferably fiber-reinforced, concrete. Particularly preferably, both the side wall elements and the base plate are made in one piece from ultra-high-strength, preferably fiber-reinforced, concrete.

[0047] A further embodiment of the invention provides that the tank further comprises a cover element which can be placed on the side elements, wherein the cover element is placed on the side wall elements in the operating state in order to hold the side wall elements in position and delimits the storage volume in a height direction. Although the side edge closure sections are designed to be self-locking or self-clamping, in particular when the side wall elements are designed as inner wall elements and outer wall elements, when the storage volume is filled with a liquid, the stability of the tank before filling can be improved by providing the cover element. The cover element can also be used, in particular in underground orburied tanks, increase operational reliability and reduce space requirements, since the cover element physically limits the storage volume on all sides and can, if necessary, be arranged entirely underground, for example by covering the cover element with earth.

[0048] The cover element also protects the liquid stored in the storage volume from environmental influences, such as direct sunlight, which minimizes loss through evaporation, especially in a water-filled tank. It should be noted that the inside of the cover element can also be provided with a sealing film to seal the storage volume from the environment.

[0049] For example, the cover element can be placed on the uppermost sections of the side wall elements in the vertical direction and encompass them, so that the side wall elements designed as inner wall elements can no longer be displaced toward the center point when the cover element is placed in place in the operating state. Advantageously, the cover element can also be used to fix the sealing film, either by providing appropriate fastening elements, such as hooks, and / or by clamping the sealing film between the side wall elements and the cover element.

[0050] In order to ensure the supporting function of the cover element in a simple manner, a further embodiment of the invention provides that the cover element has an inner supporting surface for supporting surfaces of the side wall elements facing the storage volume and / or an outer supporting surface for supporting surfaces of at least the first side wall elements, preferably the first and second side wall elements, facing away from the storage volume. The inner supporting surface serves to prevent the side wall elements, in particular the side wall elements designed as inner wall elements, from tipping or shifting inwards, while the outer supporting surface is provided as an additional stability-enhancing measure, in particular to prevent the side wall elements from bulging outwards.It is particularly advantageous if the inner support surface is formed by a circumferential, preferably continuous, inner support projection. The outer support surface can be formed by individual, separate outer support projections or, alternatively, also by a circumferential outer support provision.

[0051] According to a further embodiment of the invention, the side wall elements comprise a plate-shaped base body, wherein the respective base plate connecting sections and the respective side edge closing sections protrude from the plate-shaped base body. In detail, each first side wall element has a plate-shaped base body, from which the first side edge closing sections and the first base plate connecting section protrude. Analogously, each second side wall element has a plate-shaped base body, from which the second side edge closing sections and the second base plate connecting section protrude. The plate-shaped base body essentially fulfills the function of a wall or a wall element, while the protruding sections ensure stability in the operating state.This design enables, on the one hand, simple and cost-effective production, either in a single piece or multi-piece design, and, on the other hand, particularly efficient transport, since only small cavities are created when the side wall elements are stacked, caused by the protruding sections.

[0052] The plate-shaped design of the base body does not preclude any stiffening geometries, such as stiffening ribs, which may be provided in further design variants - in particular on the outer surfaces of the side wall elements.

[0053] For certain uses of the tank, in particular for use as a stratified storage tank, it is advantageous if the storage volume is thermally insulated from the environment. Therefore, according to a further embodiment of the invention, the side wall elements and / or the base plate, preferably and / or the cover element, have a thermal insulation layer. It is particularly advantageous if all elements that delimit the storage volume have at least one thermal insulation layer. The thermal insulation layer can be arranged in the form of a sandwich structure in the interior of the elements or the base plate or between the sealing film and the wall delimiting the storage volume and / or on an outer side of the wall facing away from the center point, in particular an outer side of the side wall elements.A thermal insulation layer can also comprise multiple sublayers, such as polyphenol foam, XPS panels, aerogel, Calcostat, or vacuum insulation materials, as well as metal foils such as aluminum foil. The combination of insulation layers or sublayers is selected based on the desired reduction in thermal conductivity, as well as the specific sensitivity of the materials to compressive and / or mechanical stress.

[0054] The at least one thermal insulation layer can already be attached to the side wall elements in the delivery state in order to further simplify the assembly process on the one hand and to simplify transport on the other hand, in particular if the thickness of the at least one insulation layer is at least as large as the extension of the base plate connecting sections in the same direction, so that the cavities can be minimized during transport.

[0055] A tank according to the invention is particularly suitable for use as a stratified storage tank in which thermal energy can be stored as hot water over a longer period of time and withdrawn when required, also known as a stratified storage tank, stratified storage tank or thermosiphon storage tank. Heated water is usually supplied to the stratified storage tank using solar thermal energy or, if appropriate, another heat source, whereby the heated water is supplied by means of a storage lance unit which is designed to supply the heated water to different storage layers in the storage volume depending on its temperature level and density, preferably while minimizing turbulence.The hottest storage layer forms in the uppermost area of ​​the storage volume, i.e. particularly close to the cover element, while the coldest layer forms in the lowest area of ​​the storage volume, i.e. near the base element. It should be noted that, in principle, liquids other than water can also be used as a filling medium for the stratified storage tank; however, the use of water is advantageous if tempered domestic water is to be made available directly from the storage volume without the need for an additional heat exchanger element and a separate circuit.

[0056] Stratified storage tanks are usually used as heat storage, with warm and / or hot water being drawn off as service water. However, it is also conceivable for stratified storage tanks to be used as cold storage, with cold or chilled water being drawn off as service water. In both cases, the stratified storage tank comprises a water supply and withdrawal device for this purpose, with the storage lance unit usually being part of the water supply device. It is also conceivable for cold water to be drawn from the stratified storage tank, heated via a heat exchanger unit, preferably by means of solar thermal energy, and then recycled into the storage volume via the water supply device, in particular the storage lance unit. Analogously, in the case of a cold storage tank, warm water can be drawn off, cooled and then recycled.

[0057] To use the tank as a stratified storage tank, it must be sealed with a cover element, as described above. Since in this case the cover element limits the storage volume, the inside of the cover element is also lined with the sealing film. For a simple design, the water supply and extraction system is also routed through the cover element.

[0058] For the storage of heat or cold, sufficient thermal insulation is required to store the stored heat or cold over a period of several days, preferably several weeks or even months, with the least possible loss. High-performance thermal insulation materials are advantageously used for this purpose, with thermal conductivities of less than 0.03 mW / mK, in particular 0.0025 mW / mK, being the goal. As previously mentioned, multi-layer insulation layers made of different materials can also be used.

[0059] To enable the internal pressure in the storage volume to be equalized with atmospheric pressure, so that pressure differences due to temperature fluctuations or the removal / supply of water can be compensated.

[0060] Accordingly, the present invention also relates to a stratified storage tank comprising a tank according to the invention, wherein the tank comprises a cover element, which is preferably designed as described above, wherein the side wall elements, the base plate and the cover element of the tank have at least one thermal insulation layer; a water supply and removal device guided through the cover element; a storage lance unit for forming storage layers with different temperature levels within the storage volume; a pressure equalization arrangement formed in the cover element.

[0061] If the heat or cooling demand cannot be met with a stratified storage tank, especially if the dimensions of the tank are optimized for road transport, two or more than two stratified storage tanks can be connected to a single consumer system and / or a heat exchange system.

[0062] A further embodiment of the stratified storage tank provides that the pressure equalization arrangement comprises a heat exchange and storage element and / or that the water supply and removal device comprises at least one thermally insulated immersion pipe for the introduction or removal of cold water in the area of ​​the base plate.

[0063] To minimize heat loss in the case of a heat storage device, a heat exchange and storage element can be arranged in the pressure equalization arrangement. This heat exchange and storage element is heated by the outflowing air, stores the heat, and subsequently warms the inflowing cold air. The heat exchange and storage element preferably has a large surface area and is made of a material with high heat storage capacity. Honeycomb structures made of ceramic, for example, are particularly suitable for use as a heat exchange and storage element.

[0064] By providing a thermally insulated immersion pipe as part of the water supply and extraction system, cold water can flow through the immersion pipe without any significant heat exchange with the warm storage layers in the upper area of ​​the storage volume.

[0065] The invention also relates to a method for installing a tank according to the invention comprising the following steps:

[0066] - Placing and aligning the base plate;

[0067] - Positioning at least two first side wall elements on an inner surface of the base plate, wherein the first side wall elements are moved outwards from the direction of the center point until the first base plate connecting sections are positively received in the corresponding first receiving sections of the base plate;

[0068] - Positioning a second side wall element on the inner surface of the base plate between two adjacent first side wall elements, wherein the second side wall element is moved outwards from the direction of the center point until, on the one hand, its second base plate connecting portion is positively received in the corresponding second receiving portion of the base plate and, on the other hand, its second side edge closure portions are positively received in the adjacent first side edge closure portions of the adjacent first side wall elements;

[0069] - Positioning at least one further second side wall element until the storage volume is closed and each side wall element is locked to the base plate and the two adjacent side wall elements;

[0070] - Lining the storage volume with the plastic sealing film;

[0071] - if necessary, fill the storage volume with the liquid.

[0072] The placement and alignment of the base plate can also be achieved by concreting it on site. In any case, a horizontal alignment of the base plate is preferred in the vast majority of applications.

[0073] As already explained in detail in connection with the construction of the tank, locking the various side wall elements by inserting a second side wall element between two first side wall elements so that the side edge locking sections engage with each other, together with locking the base plate connecting sections of the side wall elements with the receiving sections of the base plate, results in a particularly stable construction that can be achieved with little manipulation effort. Typically, only a crane and at least one worker are required to assemble the individual elements of the tank, which are preferably delivered by truck, to form the tank.

[0074] If the tank to be installed comprises more than four side wall elements, i.e., correspondingly more than two first and second side wall elements, all of the first side wall elements can, for example, be positioned first, followed by all of the second side wall elements. Alternatively, it is also possible to first position two first side wall elements and the second side wall element arranged between them, and then alternately position a first and a second side wall element until the last second side wall element engages with the first side wall element arranged first.

[0075] During installation, aids such as support or holding structures may also be used, in particular to hold the first side wall elements in position before locking by the second side wall elements.

[0076] Once the tank has been constructed and the storage volume has been lined with a plastic sealing film, the tank can be filled with the medium to be stored, preferably water. If it is to be used as a stratified storage tank, the additional elements, in particular the water supply and extraction device, must still be installed and connected to the corresponding existing systems. Advantageously, the water supply and extraction device is connected on the one hand to a solar thermal system, by means of which the water in the storage volume is extracted, preferably in a circuit, heated and fed back into the corresponding storage layer, and on the other hand to a consumer, for example a warm and hot water system in a residential building, by means of which warm and hot water, in particular for heating purposes, can be drawn off.If the extracted water, especially hot water used directly as domestic water, is not recycled, a cold water supply unit is usually also provided to supply fresh cold water.

[0077] To simplify the underground arrangement of the tank to be installed, particularly without having to move the already assembled tank as a unit, it is advantageous to assemble the tank directly in an excavation pit. Therefore, a further embodiment of the invention provides for the base plate to be placed in an excavation pit. As already mentioned, the base plate can also be manufactured, in particular cast, directly in the excavation pit before the side wall elements are erected.

[0078] SHORT DESCRIPTION OF THE CHARACTERS

[0079] The invention will now be explained in more detail using exemplary embodiments. The drawings are examples and are intended to illustrate the inventive concept, but in no way restrict it or represent it exhaustively.

[0080] It shows:

[0081] Fig . 1 is a schematic exploded view of a

[0082] Basic structure of a tank according to the invention;

[0083] Fig. 2a to 2d are schematic three-dimensional representations of various stages during the installation of a tank according to the invention;

[0084] Fig. 3a to 3d corresponding schematic floor plans to Figures 2a to 2d;

[0085] Fig. 4 is a three-dimensional representation of a tank ready for operation with a lifted cover element;

[0086] Fig . 5 a first sectional view of a

[0087] Layered storage tank;

[0088] Fig . 6 a second sectional view through the

[0089] Layered storage tank;

[0090] Fig . 7 Detail A from Fig . 6 ;

[0091] Fig . 8 a three-dimensional representation of a

[0092] Underside of a cover element;

[0093] Fig. 9 is a schematic exploded view of a second embodiment of the tank. WAYS OF IMPLEMENTING THE INVENTION

[0094] Fig. 1 shows an exploded view of a tank 1 according to the invention. In the embodiment shown, the tank 1 comprises a base plate 3 and four side wall elements 5, 6, namely two first side wall elements 5 and two second side wall elements 6, which together delimit a storage volume 2. The tank 1, in particular the storage volume 2, therefore has essentially the shape of a prism with a rectangular base area - that is to say a cuboid. In alternative embodiments, any desired even number of side wall elements 5, 6 can be provided, one half being designed as first side wall elements 5 and the other half as second side wall elements 6.

[0095] In the present embodiment, the tank 1 is designed as a concrete tank, with the side wall elements 5, 6 and the base plate 3 being made at least partially of ultra-high-strength concrete or ultra-high-performance concrete. In principle, it would also be conceivable for the base plate 3 to be made at least partially or entirely of a different type of concrete.

[0096] The side wall elements 5, 6 are essentially plate-shaped in order to form the side walls of the tank 1, however, the first side wall elements 5 have first base plate connecting sections 7a and first side edge closure sections 8a and the second side wall elements 6 have second base plate connecting sections 7b and second side edge closure sections 8b, the functioning of which is explained in more detail below. The side edge closure sections 8a, 8b run - in the operating state of the tank 1 - parallel to a height direction, while the base plate connecting sections 7a, 7b are aligned so as to run normal to the height direction.

[0097] In the present embodiment, the side wall elements 5, 6 thus comprise a plate-shaped base body and floor plate elements projecting from this base body.

[0098] Connecting sections 7a, 7b and side edge closure sections 8a, 8b.

[0099] The base plate 3 is also formed as a concrete part and has a first receiving portion 4a and a second receiving portion 4b, which are designed to engage with the base plate connecting portions 7a, 7b of the side wall elements 5, 6. In the present embodiment, the receiving portions 4a, 4b protrude vertically from the base plate 3.

[0100] A center point M of the base plate 3 is used as a reference point for the following considerations, which center point is preferably arranged on a center axis of the base plate 3 running in the height direction. Those surfaces that face the center point M when the tank is assembled and brought into the operating state are referred to as inner surfaces, while those surfaces that face away from the center point in the operating state are referred to as outer surfaces.

[0101] The basic concept of the tank 1 is based on the fact that the use of ultra-high-strength concrete as the main material enables a thin-walled design, at least for the side wall elements 5, 6. In the present exemplary embodiment, the thickness of the side wall elements 5, 6 (relative to their plate-shaped base body) is between 1.5 cm and 5 cm, preferably between 2 cm and 5 cm, which corresponds to a reduction of at least 50% compared to conventional concrete elements.

[0102] Advantageously, fiber-reinforced ultra-high-strength concrete is used to manufacture the side wall elements 5, 6 in order to increase their flexibility, allowing them to withstand slight plastic deformations without fracture. In the present exemplary embodiment, glass fiber mats and / or plastic grids are incorporated into the ultra-high-strength concrete in multiple layers, so that concrete layers and fiber layers alternate, with the concrete layers forming the cover layers.

[0103] Another important aspect of the tank 1 according to the invention is the so-called self-clamping or self-locking connection of the side wall elements 5, 6 to one another and, in the present embodiment, also of the side wall elements 5, 6 to the base plate 3, which enables installation of the tank 1 without the need for additional connecting means, such as screws or bolts. In other words, the tank 1 can thus be installed completely without any connecting means.

[0104] The self-locking or self-locking effect can basically be described as the fact that the connections between the elements are reinforced by filling the tank 1 with a liquid. The internal pressure exerted by a liquid in the storage volume 2 in the tank 1 increases the clamping forces acting between the elements. This greatly increases the stability of the tank 1 when filled and largely prevents any unintentional breakage or separation of the walls of the tank 1.

[0105] Accordingly, the first side edge closure sections 8a of the first side wall elements 5 and the second side edge closure sections 8b of the second side wall elements 6 are designed such that a first side edge closure section 8a of a first side wall element 5 engages in a form-fitting manner with an adjacent second side edge closure section 8b of an adjacent second side wall element 6 and the internal pressure exerted by the liquid on the inner surfaces 5a, 6a of the side wall elements 5, 6 reinforces the mutual clamping force in the side edge closure sections 8a, 8b. In order to achieve this behavior, the first side wall elements 5 are designed as outer wall elements and the second side wall elements 6 as inner wall elements.The first side wall elements 5 designed as outer wall elements form, in simple terms, an outer frame into which the second side wall elements 6 designed as inner wall elements are inserted.

[0106] For this purpose, the first side edge closure sections 8a are arranged on an inner surface 5a of the first side wall elements 5, i.e., directed inward, and the second side edge closure sections 8b are arranged on the outer surfaces 6b of the second side wall elements 6, i.e., directed outward. The process of sliding into one another and locking, as well as the individual required steps, are shown in Figures 2a to 2d and 3a to 3d.

[0107] In detail, the self-clamping or self-locking effect of the connection of the side wall elements 5, 6 to one another in the present embodiment is achieved by a wedge-shaped design of the side edge closure sections 8a, 8b, i.e. the side edge closure sections 8a, 8b essentially have a cross-sectional area in the form of a right-angled triangle.

[0108] The first side edge closure sections 8a of the first side wall elements 5 designed as outer wall elements are designed as outer wedges, so that their hypotenuse faces the inner surface 5a of the first side wall element 5 and a wedge-shaped receiving volume is accordingly formed between the corresponding first side edge closure sections 8a and the inner surface 5a.

[0109] The second side edge closure sections 8b of the second side wall elements 6 designed as inner wall elements are shaped as inner wedges, opposite to the first side edge closure sections 8a designed as outer wedges, so that their hypotenuse is directed outwards. This allows the inner wedges to be pushed into the outer wedges (cf. Fig. 2c / 2d and Fig. 3c / 3d), so that the second side edge closure sections 8b can be pushed into the receiving volumes formed by the first side edge closure sections 8a. As soon as the pushing-in process is finished, the connected side wall elements 5, 6 can only be released by pushing the respective second side wall elements 6 in the opposite direction towards the center point M and subsequently removing them.The internal pressure in the storage volume, however, acts in the insertion direction, so that the clamping force acting between the side edge closure sections 8a, 8b is amplified by the internal pressure. The inner wedges and the outer wedges each have a wedge angle of 45°, although other combinations of corresponding angles are also conceivable in alternative embodiments.

[0110] Although it is certainly conceivable in alternative embodiments that the self-clamping or self-locking effect is formed only between the side edge closure sections 8a, 8b of the side wall elements 5, 6, in the present embodiment the connection of the side wall elements 5, 6 to the base plate 3 is not only based on a pure form fit, but on the principle described above.

[0111] Accordingly, both the first base plate connecting sections 7a of the first side wall elements 5 and the second base plate connecting sections 7b of the second side wall elements 6 are arranged on the respective outer surfaces 5b, 6b of the side wall elements 5, 6, and are thus directed outward. The receiving sections 4a, 4b of the base plate 3, into which the base plate connecting sections 7a, 7b can be positively received, are correspondingly directed inward.

[0112] Accordingly, floor plate connecting sections 7a, 7b of the

[0113] Side wall elements 5, 6 and the receiving sections 4a, 4b of the base plate 3, designed such that in each case a first base plate connecting section 7a of a first side wall element 5 engages positively in a first receiving section 4a and a second base plate connecting section 7b of a second side wall element 6 engages positively in a second receiving section 4b, wherein the internal pressure exerted by the liquid on the inner surfaces 5a, 6a of the side wall elements 5, 6 reinforces the mutual clamping force between the base plate connecting sections 7a, 7b and the receiving sections 4a, 4b.

[0114] In the present exemplary embodiment, the geometries of the base plate connecting sections 7a, 7b and the receiving sections 4a, 4b are designed analogously to the above-described geometries of the side edge closure sections 8a, 8b. Accordingly, the receiving sections 4a, 4b are designed as outer wedges which protrude from the inner surface 3a of the base plate 3, with the hypotenuse facing the inner surface 3, so that wedge-shaped receiving volumes are formed. The base plate connecting sections 7a, 7b are designed as inner wedges which can be inserted in a form-fitting manner into the receiving volumes of the receiving sections 4a, 4b. The receiving sections 4a, 4b define the final position of the side wall elements 5, 6 relative to the base plate 3 in the ready-to-use state.

[0115] In the operating state, each side wall element 5, 6 is thus held firmly in place at its lower edge in relation to the base plate 3 via the interaction of the corresponding base plate connecting section 7a, 7b and receiving section 4a, 4b, while the engagement of the side edge closure sections 8a, 8b on the side edges of the side wall element 5, 6 ensures the stability of the side wall elements 5, 6 relative to one another.

[0116] In the present exemplary embodiment, the side wall elements 5, 6 are formed as solid concrete parts, i.e., the plate-shaped base bodies are formed integrally with the respective floor panel connecting sections 7a, 7b and side edge closure sections 8a, 8b. The side wall elements 5, 6 and, if applicable, also the floor panel are made entirely of ultra-high-strength, fiber-reinforced concrete, as previously described.

[0117] In the one-piece design, in particular the connection between the first side edge closure sections 8a and the base body of the first side wall elements 5 and the connection between the receiving sections 4a, 4b and the base plate 3 is made by a connecting section made of ultra-high-strength, preferably fiber-reinforced, concrete (see also Figures 5 to 7). In other words, the concrete connecting sections function as a rigid "concrete joint". Preferably, the connecting sections are also thin-walled, in particular between 1 cm and 2 cm thick. If fabric layers are incorporated into the ultra-high-strength concrete, it is particularly advantageous if the fabric layers extend from the first side wall elements 5 via the concrete joints into the first side edge closure sections 8a or from the base plate 3 via the concrete joints into the receiving sections 4a, 4b.

[0118] In alternative embodiments, the sections 7a, 7b, 8a, 8b could also be designed as separate elements that are connected to the base bodies.

[0119] Figures 2a to 2d and the corresponding figures 3a to 3d show the steps required for the installation or setting up of the tank 1:

[0120] In a first step (Figs. 2a and 3a), the first side wall elements 5 are placed on the base plate 3 and aligned so that the first base plate connecting sections 7a can be inserted into the first receiving sections 4a of the base plate 3 and the first side edge closing sections 8a are correctly oriented for the fourth step. In order to enable this step and the fourth step, an opening is provided between the first receiving sections 4a and the second receiving sections 4b running perpendicular thereto. While in the present embodiment, for the sake of clarity, no continuous wall, for example in the form of a support frame 24, is provided to connect the receiving sections 4a, 4b to one another, in alternative embodiments an outer stiffening wall, preferably in the form of the support frame 24 (see Fig.9 ) is provided, which is arranged outside the receiving sections 4a, 4b as seen from the center point M in order to increase the stability of the receiving sections 4a, 4b.

[0121] In a second step (Fig. 2b and 3b), the first side wall elements 5 are displaced outwards in the direction of the first receiving sections 4a until the first base plate connecting sections 7a are received and locked in the first receiving sections 4a.

[0122] In a third step (Figs. 2c and 3c), the two second side wall elements 6 are placed in the center of the base plate 3 and aligned parallel to the second receiving sections 4b. The second side wall elements 6 already support the first side wall elements 5 laterally, so that they can no longer be displaced inward.

[0123] In a fourth step (Fig. 2d and 3d), the first side wall elements 5 are finally displaced outwards in the direction of the second receiving sections 4b until the second base plate connecting sections 7b are received and locked in the second receiving sections 4b and until the second side edge locking sections 8b are received in the first side edge locking sections 8a of the already positioned first side wall elements 5.

[0124] Figure 4 now shows a tank 1 in the operating position, wherein a cover element 10 is provided to limit the storage volume 2 at the top. The cover element 10, which is shown in detail in Fig. 8, can be placed on top of the side wall elements 5, 6 in a simple manner and thus holds the side wall elements 5, 6 in position. For this purpose, the cover element 10 has on its underside a circumferential inner support projection 11 with an inner support surface 11a, on which inner support surface 11a the inner surfaces 5a, 6a of the side wall elements 5, 6 can be supported, and the cover element 10 has two outer support projections 12, each with an outer support surface 12a, on which the outer surfaces 5b, 6b of the upper edges of the side wall elements 5, 6 can be supported (cf. Figures 5, 6 and 8).Thus, the attached cover element 10 prevents both a "falling in" of the second side wall elements 5, 6 when the tank 1 is unfilled and a "bulging" along the upper edge of the side wall elements 5, 6 when the tank 1 is filled.

[0125] Furthermore, Fig. 4 shows for the first time that the present embodiment comprises a sealing film 9 made of plastic (see also Figs. 5 and 6), by means of which the storage volume 2 is lined. The sealing film 9 ensures the tightness of the storage volume 2 without the connection between the side wall elements 5, 6 or between the side wall elements 5, 6 and the base plate 3 having to be tight. Furthermore, neither damage to the side wall elements 5, 6 directly leads to the failure of the tank 1, nor can roots penetrate into the tank 1 and damage the sealing film 9 in the desired state.

[0126] In the present embodiment, the plastic sealing film 9 has a thickness of between 0.2 mm and 1 mm, preferably between 0.5 mm and 0.8 mm. In principle, any film material that is dimensionally stable up to 100°C can be used as the material for the plastic sealing film 9. Polypropylene films or polycarbonate films are preferred, which are welded using standard film welding devices. After the sealing film 9 has been welded in the factory to produce the shape of the storage volume 2, the prefabricated sealing film 9 can be folded or rolled up for transport. After the side wall elements 5, 6 have been assembled, the pre-welded sealing film 9 is placed in the tank 1 and can be installed by unfolding, inflating or unrolling. The sealing film 9 is subsequently either attached to the cover element 10, clamped between the side wall elements 5, 6 and the cover element 10 or attached to the outer surfaces 5b, 6b of the side wall elements.Since the sealing film 9 is not bonded to the side wall elements 5, 6, relative movements and deformations of a few centimeters, and even cracks in the side wall elements 5, 6, which may occur due to movements of the surrounding substrate, are possible without any risk of leakage. Due to the maximum service life of the sealing film 9, it must be replaced at regular intervals, with an average service life of 10 to 15 years generally being given.

[0127] Particularly if the tank 1 is to be used as a stratified storage tank, at least one thermal insulation layer 9 is also provided to minimize heat loss to the environment. In the present exemplary embodiment, an insulation composite comprising an aluminum foil and a thermal insulation panel as insulation layers 13 is attached to the outer sides of the side wall elements 5, 6.

[0128] Figures 5 and 6 show sectional views through a tank 1 designed as a stratified storage tank, the two views differing essentially in the components of their water supply and withdrawal device 14. To begin with, the features visible in the two sectional views will now be discussed.

[0129] The section shows the storage volume 2, which is bounded laterally by the inner surfaces 5a of the first side wall elements 5, on the underside by the inner surface 3a of the base plate 3, and on the top by the cover element 10. On the front and rear sides located in front of and behind the image plane, the storage volume 2 is bounded by the inner surfaces 6a of the second side wall elements 6.

[0130] In particular, it can be seen how the first base plate connecting sections 7a of the first side wall elements 5, designed as inner wedges, engage in or are received in the first receiving sections 4a of the base plate 3, designed as outer wedges. Furthermore, the "concrete joints" between the first receiving sections and the base plate 3 are shown, with the "concrete joints" (not shown) between the first side edge closure sections 8a and the base bodies of the first side wall elements 5 being constructed in an analogous manner.

[0131] Also shown schematically is the lining of the storage volume 2 by means of the sealing film 9 made of plastic, wherein in particular the inner surfaces 3a, 5a, 6a of the base plate 3 and the side wall elements 5, 6 are covered by the sealing film 9.

[0132] Also visible is the cover element 10 (cf. Fig. 4), whose inner and outer support surfaces 11a, 12a fix and support the upper edges of the side wall elements 5, 6.

[0133] The side wall elements 5, 6 are provided on their outer surfaces 5b, 6b with an insulation composite comprising two thermal insulation layers 13 in order to minimize heat loss to the environment, in particular the surrounding soil. The thermal insulation layer 13 of the base plate 3 is integrated into the base plate 13 in order to both ensure the stability of the tank 1 and reduce the compressive load on the insulation layer 13.

[0134] The cover element 10 also has an insulation structure comprising two insulation layers 13 on its inside.

[0135] The general principle of a stratified storage tank is well known and has already been explained at the beginning, so that only the specific features will be discussed in order to avoid unnecessary length.

[0136] Figures 5 and 6 illustrate a stratified storage tank for a heat storage device. Figure 5 illustrates that part of the water supply and withdrawal device 14 by means of which water brought to a higher temperature level can be stored, namely a storage lance unit 15, as well as the corresponding arrangement for withdrawing cold water and subjecting it to a heat exchange process, namely a cold water withdrawal unit 16.

[0137] As shown in Figure 5, in the present exemplary embodiment, cold water is withdrawn in a circulating manner via the cold water extraction unit 16, brought to a higher temperature level by a heat source (not shown), and subsequently returned to the storage volume by means of the storage lance unit 15 and fed to the storage layer corresponding to the temperature level. Solar thermal energy is preferably used as the heat source, so that only electrical energy is required for circulation, while the heat is stored during the day (or during the warmer seasons).

[0138] The schematically illustrated storage lance unit 15, which projects from the cover element 10 into the storage volume 2 and is fed via a line passing through the cover element 10, serves to store and layer water. For this purpose, each pipe of the storage lance unit 15 has a plurality of horizontal circumferential openings or tubes (not shown) along its entire length, through which water can be introduced into the corresponding layers. Automatic valves generally ensure that the water is fed into the correct storage layer.

[0139] The cold water extraction unit 16 is arranged in the area of ​​the base plate 3, where the water in the storage volume 2 generally has the lowest temperature. Via an insulated immersion pipe 19, the cold water is guided through the warmer upper storage layers to the cover element 10, where the corresponding line enters through the cover element 10.

[0140] Furthermore, a pressure equalization arrangement 20 is provided in the cover element 10 in order to be able to equalize pressure differences - which can arise from the removal and filling of the storage volume 2 and / or from temperature fluctuations within the storage volume 2 - with the atmosphere. In order to minimize heat loss, the pressure equalization arrangement 20 comprises a heat exchange and storage element 21, preferably made of ceramic, which is arranged inside the pressure equalization arrangement 20. For example, a honeycomb-shaped ceramic arrangement can be provided which heats up when hot air escapes from the tank 1 and heats cold, incoming air when it enters.

[0141] Fig. 6 shows the part of the stratified storage tank by means of which the stored hot water can be withdrawn and supplied to a consumer. Accordingly, the stratified storage tank has a hot water withdrawal unit 17 which is arranged in the region of the cover element 10, i.e. where the storage layer with the highest temperature level is located. Hot water can be withdrawn via this hot water withdrawal unit 17 and supplied to the consumer, either directly or preferably via a heat exchanger circuit. A typical application would be the provision of heat for a residential unit, whereby both warm water for space heating and hot water for direct consumption are provided.

[0142] To compensate for the amount of hot water consumed with cold water, a cold water supply device 18 is provided in the area of ​​the base plate 3. If all of the heat from the water extracted by the hot water extraction unit 17 is consumed and the water is recirculated, the water can also be recirculated via the cold water supply device 18. An insulated immersion pipe 19 is also provided for this subsystem, connecting the cold water supply device 18 to a corresponding line on the cover element 10.

[0143] If the temperature level is only reduced at the consumer or an upstream heat exchanger, a feed through the storage lance unit 15 can also be provided.

[0144] If the stratified storage tank is used as a cold storage tank, i.e., if the circulating water is brought to a lower temperature before being returned, the cold water supply device 18 is designed as a cold water extraction unit, and the hot water extraction unit 17 is designed as a warm water supply unit. A typical application would be the cooling of residential units, particularly in those regions of the world where temperatures are very high during the day and relatively low at night.

[0145] Fig. 7 shows an example of a structural detail of the design of the base plate connecting sections 7a, 7b and the receiving sections 4a, 4b, whereby the same principles can also be applied to the side edge closure sections 8a, 8b.

[0146] In order to reduce the amount of concrete required and to avoid material accumulation, which on the one hand has a positive effect on stability and on the other hand leads to a reduction in weight, internal displacement elements 22 can be incorporated, in particular cast, into the floor slab connecting sections 7a, 7b or the receiving sections 4a, 4b. These internal displacement elements 22 can be hollow bodies, such as pipes or shaped pipes with a prismatic outline, in particular triangular shaped pipes, as shown by way of example in the first floor slab connecting section 7a, or solid bodies made of a material with a lower density, such as insulation material, as shown by way of example in the first receiving section 4a.In principle, any combination is possible, although it is advantageous for manufacturing purposes to use the same design in all sections 3, 7, 8 in which internal displacement elements 22 are desired. Fig. 7 also shows the "concrete joints" between the first receiving sections 4a and the base plate 3 in detail.

[0147] Fig. 8 shows a representation of the cover element 10 seen from the underside, i.e. from the center point M. On the one hand, the continuously circumferential first support projection 11 with the inner support surfaces 11a for supporting the inner surfaces 5a, 6a of the side wall elements 5, 6 can be seen. Furthermore, in the present exemplary embodiment, two separately formed outer support projections 12 can be seen which, in the operating state, support the outer surfaces 5b of the first side wall elements 5, as described above. Finally, an access opening 23 can also be seen, via which the storage volume 2 is accessible from the outside for maintenance work, for example on the water supply and withdrawal unit 14 or for replacing the sealing film 9.

[0148] In alternative embodiments, outer support projections 12 are preferably also provided for the outer surfaces 6b of the second side wall elements 6, wherein these outer support projections 12 can be offset inward relative to the outline of the cover element 10. Alternatively, the outer support surface 12a can also be formed by a circumferential outer support projection 12.

[0149] In the illustrated embodiments, a tank 1 with a cuboid storage volume 2 can be seen, wherein the inner surfaces 5a, 6a of the side wall elements 5, 6 form the shape of a rectangle in plan view. In alternative embodiments, the plate-shaped base bodies of the side wall elements 5, 6 can also have an offset section, i.e. a section offset outwards and running parallel to the basic direction of the side wall elements 5, 6. Furthermore, for the sake of clarity, it is pointed out that the described structure and the system used for producing self-locking or self-clamping connections are also suitable for polygonal floor plans with an even number of side wall elements 5, 6, wherein a first side wall element 5 and a second side wall element 6 are arranged alternately one after the other.Thus, tanks 1 with a hexagonal or octagonal layout can also preferably be manufactured. The number of side wall elements 5, 6 particularly influences the size of the angles of the side edge closure sections 8a, 8b, whereby the theoretical number of side wall elements 5, 6 is practically limited by the achievement of self-locking angles.

[0150] Fig. 9 shows a second embodiment of the tank 1, showing two different design measures that can also be implemented independently of each other.

[0151] On the one hand, it can be seen that the two second side edge closure sections 8b of a second side wall element each merge into the second base plate connecting section 7b at the lower end, forming a frame-like structure closed on three sides, which increases the stability of the sections 7b, 8b relative to one another. The first side edge closure sections 8a have a correspondingly shaped recess to enable the first and second side edge closure sections 8a, 8b to be pushed together over their entire length in the operating state.

[0152] On the other hand, a reinforced design variant of the base plate 3 or the receiving sections 4a, 4b is shown. In order to improve the connection between the receiving sections 4a, 4b and the base plate 3 and to increase the mechanical load-bearing capacity, a support frame 24 is provided, which is formed integrally with the base plate 3 and the receiving sections 4a, 4b, preferably also from fiber-reinforced ultra-high-strength concrete. The support frame 24 is arranged on the outer side of the receiving sections 4a, 4b in such a way that the insertion of the first side wall elements 5 from above is still possible. The support frame 24 prevents, in particular, a "tearing off" of the receiving sections 4a, 4b as a result of, for example, uneven load distribution.

[0153] LIST OF REFERENCE SYMBOLS

[0154] tank

[0155] Spei rather vo lumen

[0156] Base plate a Inner surface of the base plate 3

[0157] Receiving sections a first receiving sections b second receiving sections first side wall element a inner surface of the first side wall element 5b outer surface of the first side wall element 5 second side wall element a inner surface of the second side wall element 6b outer surface of the second side wall element 6

[0158] Floor plate connecting sections a first floor plate connecting sections of the first

[0159] Side wall element 5 b second floor plate connecting sections of the second side wall element 6

[0160] Side edge closure sections a first side edge closure sections of the first

[0161] Side wall element 5 b second side edge closure sections of the second side wall element 6

[0162] Sealing film

[0163] Cover element inner support projection a inner support surface outer support projection a outer support surface thermal insulation layer

[0164] Water supply and extraction device

[0165] Storage lance unit 16 Cold water extraction unit

[0166] 17 Hot water dispensing unit

[0167] 18 Cold water supply unit

[0168] 19 Immersion tube 20 Pressure compensation arrangement

[0169] 21 Heat exchange and storage element

[0170] 22 inner displacement body

[0171] 23 Access opening

[0172] 24 support frames

Claims

PATENT CLAIMS 1. A tank (1) for storing liquids, wherein the tank (1) comprises a base plate (3) having a center point (M), as well as at least two first plate-shaped side wall elements (5) and at least two second plate-shaped side wall elements (6), wherein the base plate (3) together with the side wall elements (5, 6) delimit a storage volume (2) of the tank (1) in an operating state, wherein at least the side wall elements (5, 6) are at least partially made of ultra-high-strength concrete, characterized in that the storage volume (2) is lined by a plastic sealing film (9), the first side wall elements (5) have first base plate connecting sections (7a), which, in the operating state, are inserted in a form-fitting manner into first receiving sections (4a) of the base plate (3), the second side wall elements (6) have second base plate connecting sections (7b),which, in the operating state, are inserted in a form-fitting manner into second receiving sections (4b) of the base plate (3), the first side wall elements (5) each have two first side edge closure sections (8a), the second side wall elements (6) each have two second side edge closure sections (8b), and that in the operating state, a second side edge closure section (8b) of a second side wall element (6) engages in a form-fitting manner in a first side edge closure section (8a) of an adjacent first side wall element (5) in such a way that a pressure exerted on the side wall elements (5, 6) by a liquid located in the storage volume (2), Pressure force reinforces a clamping force acting alternately between the interlocking first side edge closure sections (8a) and second side edge closure sections (8b).

2. Tank (1) according to claim 1, characterized in that the ultra-high-strength concrete is fiber-reinforced, preferably has a multi-layer structure.

3. Tank (1) according to one of claims 1 to 2, characterized in that the side wall elements (5, 6) are thin-walled and have a thickness of between 1 cm and 8 cm, preferably between 1.5 cm and 5 cm, in particular between 2 cm and 4 cm.

4. Tank (1) according to one of claims 1 to 3, characterized in that the first side edge closure sections (8a) are arranged on a side of the first side wall elements (5) facing the center point (M) in order to form outer wall elements, and the second side edge closure sections (8b) are arranged on a side of the second side wall elements (6) facing away from the center point (M) in order to form inner wall elements, wherein in the operating state the second side edge closure sections (8b) of one of the second side wall elements (6) designed as inner wall elements are pushed from the direction of the center point (M) into the respective first side edge closure sections (8a) of the two adjacent first side wall elements (5) designed as outer wall elements.

5. Tank (1) according to one of claims 1 to 4, characterized in that the base plate connecting sections (7a, 7b) are each arranged on a side of the side wall elements facing away from the center point (M) (5, 6) are arranged to form a space between the respective interlocking floor plate Connecting sections (7a, 7b) of the side wall elements (5, 6) and the receiving sections (4a, 4b) of the base plate (3) by a pressure force exerted on the side wall elements (5, 6) by a liquid located in the storage volume (2).

6. Tank (1) according to one of claims 1 to 5, characterized in that the side edge closure sections (8a, 8b) of the side wall elements (5, 6) are wedge-shaped, wherein the first side edge closure sections (8a) are designed as outer wedges, which outer wedges each form a wedge-shaped receiving volume with an inner surface (5a) of the respective first side wall element (5) and the second side edge closure sections (8b) are designed as inner wedges which can be inserted into the receiving volumes of the first side edge closure sections (8a).

7. Tank (1) according to one of claims 1 to 6, characterized in that the base plate connecting sections (7a, 7b) of the side wall elements (5, 6) and the receiving sections (4a, 4b) of the base plate (3) are wedge-shaped, wherein the receiving sections (4a, 4b) are designed as outer wedges, which outer wedges each form a wedge-shaped receiving volume with an inner surface (3a) of the base plate (3), and the base plate connecting sections (7a, 7b) are designed as inner wedges which can be inserted into the receiving volumes of the receiving sections (4a, 4b).

8. Tank (1) according to one of claims 1 to 7, characterized in that the first side edge closure sections (8a) are formed integrally with the first side wall elements (5) and / or that the second side edge closure sections (8b) are formed integrally with the second side wall elements (6).

9. Tank (1) according to one of claims 1 to 8, characterized in that the first base plate connecting sections (7a) are formed integrally with the first side wall elements (5) and / or that the second base plate connecting sections (7b) are formed integrally with the second side wall elements (6).

10. Tank (1) according to one of claims 1 to 9, characterized in that the first receiving sections (4a) and the second receiving sections (4b) are formed integrally with the base plate (3).

11. Tank (1) according to one of claims 1 to 10, characterized in that the first side wall elements (5) and / or the second side wall elements (6) and / or the base plate (3) are made of ultra-high-strength, preferably fiber-reinforced, concrete.

12. Tank (1) according to one of claims 1 to 11, characterized in that the tank (1) further comprises a cover element (10) which can be placed on the side elements (5, 6), wherein the cover element (10) is placed on the side wall elements (5, 6) in the operating state in order to hold the side wall elements (5, 6) in position and limits the storage volume (2) in a height direction.

13. Tank (1) according to claim 12, characterized in that the cover element (10) has an inner support surface (11a) for supporting surfaces (5a, 6a) of the side wall elements (5, 6) facing the storage volume (2) and / or an outer support surface (12a) for supporting surfaces (5b, 6b) of at least the first side wall elements (5, 6) facing away from the storage volume (2).

14. Tank (1) according to one of claims 1 to 13, characterized in that the side wall elements (5, 6) comprise a plate-shaped base body, wherein the respective base plate connecting sections (7a, 7b) and the respective side edge closure sections (8a, 8b) protrude from the plate-shaped base body.

15. Tank (1) according to one of claims 1 to 14, characterized in that the side wall elements (5, 6) and / or the base plate (3), preferably and / or the cover element (10), have at least one thermal insulation layer (13).

16. Stratified storage tank comprising a tank (1) according to one of claims 1 to 14, wherein the tank (1) comprises a cover element (10) according to claim 12 or 13, wherein the side wall elements (5, 6), the base plate (3) and the cover element (10) have at least one thermal insulation layer (13); a water supply and removal device (14) guided through the cover element (10); a storage lance unit (15) for forming storage layers with different temperature levels within the storage volume (2); a pressure equalization arrangement (20) formed in the cover element (10).

17. Stratified storage tank according to claim 16, characterized in that the pressure equalization arrangement (20) comprises a heat exchange and storage element (21) and / or that the water supply and removal device (14) at least one heat-insulated immersion tube (19) for the Introduction or removal of cold water in the area of ​​the base plate (3).

18. A method for installing a tank (1) according to any one of claims 1 to 15, comprising the following steps: - Placing and aligning the base plate (3); - positioning at least two first side wall elements (5) on an inner surface (3a) of the base plate (3), wherein the first side wall elements (5) are moved outwards from the direction of the center point (M) until the first base plate connecting sections (7a) are positively received in the corresponding first receiving sections (4a) of the base plate (3); - Positioning a second side wall element (6) on the inner surface (3a) of the base plate (3) between two adjacent first side wall elements (5), wherein the second side wall element (6) is moved outwards from the direction of the center point (M) until, on the one hand, its second base plate connecting section (7b) is positively received in the corresponding second receiving section (4b) of the base plate (3) and, on the other hand, its second side edge closure sections (8b) are positively received in the adjacent first side edge closure sections (8a) of the adjacent first side wall element (5); - positioning at least one further second side wall element (6) until the storage volume (2) is closed and each side wall element (5, 6) is locked to the base plate (3) and the two adjacent side wall elements (6, 5) by means of the side edge closure sections (8a, 8b); - lining the storage volume (2) with the plastic sealing film (9); - if necessary, fill the storage volume (2) with the liquid, preferably with water.

19. Method according to claim 18, characterized in that the base plate (3) is placed in an excavation pit.

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