Transport tray for transporting and heating chemical substances

Abstract

Transport trough (1) for transporting and heating chemical substances, comprising a one-piece support structure (2) with a base (3) and a frame (4) rigidly connected thereto, wherein the frame (4) of the support structure (2) is a circumferential frame, wherein the support structure (2) supports a lining (29) of a trough-shaped cavity (25) for receiving the chemical substances, wherein the lining (29) comprises a base plate (13) resting on the base (3) and several frame plates (14, 14') clamped against the frame (4), wherein the lining (29) is supported by the support structure (2) in such a way that the thermal expansions of the base plate (13) and frame plates (14, 14') in their planes are not impeded. wherein the frame plates (14, 14') of the lining (29) are clamped to the frame (4) by clamping strips (15), wherein the clamping strips (15) each have at least one groove (18, 18') for receiving an edge region (17, 17') of an adjacent frame plate (14, 14'), wherein the edge region (17, 17') is received with play in the groove (18, 18') of the clamping strip (15), wherein the base plate (13) of the lining (29) rests freely on the base (3) of the support structure (2) and is arranged with play within the surrounding frame (4) of the support structure (2) and the other components (14, 14') of the lining (29), so that a gap (21) exists between the base plate (13) and the frame (7), wherein the frame plates (14, 14') of the lining (29) each rest on the base plate (13) of the lining (29) without penetrating the gap (21), and wherein the lining material (29) is more corrosion-resistant than the supporting structure material (2) with respect to the chemical reaction of the same product.

Description

[0001] The present invention lies in the technical field of the thermal conversion of chemical substances in an oven and relates to a transport trough suitable and intended for transporting and heating chemical substances. Furthermore, the invention relates to the use of a transport trough according to the invention in the production of cathode materials for lithium-ion batteries.

[0002] Batteries are fundamentally divided into primary and secondary energy storage devices. While primary energy storage devices irreversibly convert chemical energy into electrical energy, secondary energy storage devices (accumulators) allow for multiple uses by enabling the reversal of the ongoing chemical reaction through the input of electrical energy. Secondary energy storage devices with an active cathode material based on lithium-ion are used in a wide variety of applications. Examples include electric and hybrid vehicles, portable computers, mobile phones, and smartwatches. The widespread use of lithium-ion batteries necessitates large quantities of active cathode materials. Global production exceeds 100,000 tons per year, with a strong upward trend.Currently, it is common to use lithium mixed metal oxides containing the transition metals nickel, manganese, and cobalt as the active cathode material. The most widely produced cathode materials are lithium nickel cobalt manganese oxide (LiNiCoMnO2) and lithium cobalt oxide (LiCoO2); lithium nickel cobalt aluminum oxide (LiNiCoAlO2) and lithium iron phosphate (LiFePO4) are produced in smaller quantities.

[0003] In the large-scale production of cathode materials for lithium-ion batteries, the respective raw materials are transported in a transport trough through a continuous furnace and heated to a temperature of several hundred degrees Celsius (e.g., 950 °C), resulting in a chemical reaction to form the desired product. The materials of the transport troughs currently in use are selected with regard to the high thermal shock resistance required for their application.

[0004] However, practical experience has shown that these materials are subject to significant corrosion. This is due to the chemical aggressiveness of the substances transported in the transport trough, which, at high temperatures, accelerates the attack on the trough material. Particularly during the production of lithium nickel cobalt manganese oxide, the highly aggressive transition metals involved result in very severe corrosion of the transport troughs. This has the disadvantageous consequence that the transport troughs only allow a relatively small number of firing cycles and subsequently need to be replaced. For example, a transport trough used in the production of lithium nickel cobalt manganese oxide can typically only be used for 20 to 40 firing cycles.To make matters worse, the transport trays contain cathode powder residue after use, which is generally classified as hazardous waste, necessitating complex and expensive disposal of the trays. This results in significant additional costs and is undesirable from an environmental perspective. Furthermore, materials from the transport tray contaminate the fuel, leading to its contamination and an overall reduction in quality.

[0005] In contrast, the object of the present invention is to improve transport trays known in the prior art in such a way that the transport trays have a high resistance to temperature changes while simultaneously having good corrosion resistance and can therefore be used more frequently than transport trays known in the prior art, which are disclosed, for example, in the documents DE 10 2005 024 957 A1, DE 10 2011 052 016 A1, WO 2004 / 111 562 A2 and EP 0 452 718 B1.

[0006] These and other problems are solved according to the invention by a transport trough for an oven, in particular a continuous oven or bogie hearth oven, according to the features of the independent claim. Advantageous embodiments of the invention are specified by the features of the dependent claims.

[0007] The invention describes a transport trough for an oven, in particular a continuous furnace or car hearth furnace. The transport trough serves as a trough-shaped container for transporting chemical substances, wherein the substances transported in the transport trough (starting materials) are to be converted into a chemical product by heating in the oven within the transport trough. In principle, any starting materials can be converted into a chemical product in the transport trough according to the invention. Particularly advantageous are starting materials for the production of an active cathode material for a lithium-ion battery, which is in particular a lithium mixed metal oxide with the transition metals nickel, manganese, and cobalt, described by the general formula LiNi x Mn y Co zO2 with x+y+z = 1. In the above formula, nickel, manganese and cobalt can each be present alone or in any combination.

[0008] The transport trough according to the invention for transporting and heating chemical substances comprises a support structure with a preferably flat base and a frame firmly connected thereto. According to the invention, the base and frame of the support structure are formed in one piece and cannot be separated from each other without damage.

[0009] The transport trough further comprises a lining (wall or boundary) of a trough-shaped cavity, composed of several components, which serves to hold the chemical substances. The lining is supported by the support structure. The lining includes a base plate placed on the floor and several frame plates fixed to the frame. Preferably, the frame plates are clamped against the frame.

[0010] Here, the base slab is supported by the supporting structure in such a way that, relative to the plane of the base slab, it has free space (clearance) in at least two orthogonal directions, so that its thermal expansion is not impeded. In other words, the base slab is supported by the supporting structure in such a way that its thermal expansion within the plane of the slab is not hindered. Advantageously, the base slab is supported by the base of the supporting structure. Preferably, the base slab has completely free space within the plane of the slab. For this purpose, the base slab is supported by the supporting structure in such a way that it has sufficient clearance (i.e., free space) within the plane of the slab so that its thermal expansion is not hindered.

[0011] Furthermore, each frame panel is fixed to the frame, preferably clamped against the frame, in such a way that it has free space (clearance) in at least two orthogonal directions within the plane of the panel, so that its thermal expansion is not impeded. In other words, each frame panel is supported by the support structure in such a way that its thermal expansion within the plane of the panel is not impeded. Advantageously, each frame panel is clamped against the frame. For this purpose, each frame panel is supported by the support structure in such a way that it has sufficient clearance (i.e., free space) within the plane of the panel so that its thermal expansion is not impeded.

[0012] The special design of the lining of the trough-shaped cavity of the transport trough, which does not impede the thermal expansion of the base and frame panels, prevents thermally induced mechanical stresses that would otherwise likely lead to material failure. The lining can therefore be made of a material with good corrosion resistance, without the risk of failure due to the typically low thermal shock resistance of such materials. Materials with low thermal shock resistance are more prone to breakage under thermally induced mechanical stress. In contrast, the material of the supporting structure, which is protected from corrosion by the lining, can be selected with a high degree of thermal shock resistance in mind.The transport tray according to the invention can thus be used far more frequently than conventional transport trays before it needs to be replaced. For example, transport trays according to the invention can be used at least 100 times more often than conventional transport trays under the same conditions.

[0013] The materials used for the lining can be selected to be highly corrosion-resistant. The structural design of the lining ensures resistance to temperature fluctuations.

[0014] With regard to thermal shock resistance, a thin lining wall is advantageous. Preferably, the wall thickness of the base and frame panels is in the range of 1.5 mm to 8.0 mm, and particularly preferably in the range of 2.0 mm to 5.0 mm. In particular, the frame panels can also be designed as a film with a wall thickness in the range of 0.3 mm to 2.5 mm. The thickness of the support structure is advantageously in the range of 6 to 12 mm and is preferably 7 mm.

[0015] The following formula clarifies the relationships: I(TWB)=(MOR×TC):(MOE×CTE×T) the abbreviations have the following meaning I(TWB): Indicator for thermal shock resistance MOR: Modulus of Rupture (flexural strength), unit: N / mm² 2 TC: Thermal Conductivity, Unit: W / m*K MOE: Young's Modulus (E-Modulus), Unit: N / m 2 CTE: Coefficient of Thermal Expansion, Unit: 1 / K T: Plate Thickness, Unit: m

[0016] In the formula above, I(TWB) is an indicator of a material's thermal shock resistance. The larger the value of I(TWB), the better the thermal shock resistance, and vice versa. Therefore, thermal shock resistance is inversely proportional to the plate thickness T; that is, the smaller the plate thickness T, the greater the thermal shock resistance.

[0017] The lining of the trough-shaped cavity, or parts thereof, can be replaced separately, while the support structure can generally be reused. The costs for producing substances using transport troughs according to the invention can thus be significantly reduced. In addition, considerably less hazardous waste is generated for disposal. Furthermore, the contamination of the combustion material is reduced, thus improving its quality.

[0018] The base plate of the lining can be made of one or more parts. Preferably, the base plate is made of one part. In the case of a multi-part base plate, it is, for example, composed of several strips. Likewise, each frame plate can be made of one or more parts, with a one-piece design being preferred.

[0019] The transport tray is advantageously designed so that no parts protrude into the tray-shaped cavity which are not part of the lining, in particular no screws that serve to fasten the frame plates.

[0020] According to an advantageous embodiment of the transport tray according to the invention, the frame plates are clamped to the frame of the support structure by clamping strips. Advantageously, two adjacent frame plates are clamped against the frame by one clamping strip. Preferably, each clamping strip has grooves for receiving the edge regions of the frame plates. The edge regions of the frame plates adjacent to a clamping strip are held with some play in the grooves of the clamping strips to allow for thermal expansion of the frame plates. The clamping strips for clamping the frame plates are advantageously clamped to the frame by threaded screws or spring-elastic clamps made of a reaction-inert ceramic material. The threaded screws or clamps used here are heat- and corrosion-resistant.Preferably, the threaded screws and clamps are made of a ceramic material such as zirconium oxide, magnesium oxide, aluminum oxide, or mixtures thereof, preferably comprising at least 80% of the material. Advantageously, the clamping strips are each clamped to a corner section of the frame.

[0021] According to an advantageous embodiment of the transport tray, the clamping strips contain aluminum oxide (Al2O3), zirconium oxide (ZrO2), magnesium oxide (MgO), or mixtures thereof, preferably at least 80%, particularly preferably at least 90%. In particular, the clamping strips can consist of aluminum oxide (Al2O3), zirconium oxide (ZrO2), magnesium oxide (MgO), or mixtures thereof.

[0022] According to a further advantageous embodiment of the transport tray according to the invention, the frame of the support structure is a closed or circumferential frame. Preferably, the circumferential frame of the support structure has plate-shaped frame sections. For example, the frame has a rectangular or square shape with two opposing (parallel) frame sections. For example, adjacent frame sections are connected to each other by an (angled) corner section, wherein the corner section is arranged at an angle of greater than 0° and less than 90° to each of the two adjacent frame sections.

[0023] Preferably, at least one plate-shaped frame section of the support structure has at least one recess, and in particular exactly one recess. Advantageously, all plate-shaped frame sections each have at least one recess, and in particular exactly one recess. The at least one recess allows for savings in weight, material, and manufacturing costs for the transport trough. Furthermore, the resulting improved heat transfer to the material being burned in the area of ​​the recess is advantageous, mitigating the disadvantage of the typically lower thermal conductivity of highly corrosion-resistant materials. Additionally, the thermal stress on the lining can be reduced.

[0024] Preferably, the at least one recess of a plate-shaped frame section of the support structure extends over at least 50%, at least 60%, at least 70%, at least 80% or at least 90% of the area of ​​the plate-shaped frame section of the frame, with an increasingly larger extent of the recess resulting in better heat transfer and greater savings in material and costs.

[0025] The at least one recess in the plate-shaped frame section of the support structure can be an internal recess, meaning it is completely surrounded by material from the frame section. In this case, the associated frame plate of the lining remains well protected against mechanical stress from the frame section of the support structure and can therefore be made extremely thin-walled. For example, the wall thickness of the frame plate ranges from 0.3 mm to 8.0 mm. For a particularly thin-walled frame plate, the wall thickness ranges from 0.3 mm to 2.0 mm.

[0026] In an alternative embodiment, at least one recess in the plate-shaped frame section of the support structure is a peripheral recess. This allows for a further increase in the recess's dimensions, resulting in even greater improvement of heat transfer to the fuel and further savings in material and costs.

[0027] According to a further advantageous embodiment of the transport trough according to the invention, the base of the support structure has a plurality of holes. This measure allows for further savings in material and costs for the transport trough. Furthermore, heat transfer to the material being processed can be further improved. Another important advantage of this embodiment is that the thermal stress on the lining can be reduced.

[0028] According to a further advantageous embodiment of the transport trough according to the invention, the frame of the support structure is not closed, but is interrupted at least once and consists of a plurality of pillars, which are designed in particular as corner pillars. The frame is completely removed between the pillars by means of recesses at the edges. In this case, the support structure consists of the base and the pillars forming the frame. This measure allows for further savings in material and costs for the transport trough. In addition, the heat transfer to the material being burned can be further improved.

[0029] According to a further advantageous embodiment of the transport tray according to the invention, the frame plates of the base plate each sit on top of the frame plates. This allows the base plate to be fixed in a direction perpendicular to the plane of the plate without hindering the thermal expansion of the base plate within that plane.

[0030] According to a further advantageous embodiment of the transport trough according to the invention, wedge-shaped corner strips are provided to cover the respective butt joints between the frame plates and the base plate. These corner strips prevent the ingress of combustible material into the area of ​​the butt joints between the frame plates and the base plate, thereby reliably and safely protecting the support structure from corrosion.

[0031] According to a further advantageous embodiment of the transport tray according to the invention, the base plate extends in the plane of the plate to beyond the frame plates. The base plate is thereby securely clamped against the base of the support structure by the frame plates, without impeding the thermal expansion of the base plate.

[0032] According to a further advantageous embodiment of the transport trough according to the invention, the support structure and the lining of the trough-shaped cavity consist of different materials, preferably selected such that the lining material is more corrosion-resistant than the support structure material with respect to the chemical reaction to form the same product. This allows the transport trough to be used more frequently, i.e., the number of firing cycles before replacement due to corrosion is increased. The lining material can thus be specifically selected with regard to its corrosion resistance during the reaction of certain starting materials to form a chemical product, thereby increasing the number of uses. Advantageously, the support structure material is chosen for its good resistance to thermal shock. However, it is also possible for the support structure and the lining to be made of the same material.

[0033] According to an advantageous embodiment of the transport tray, the lining contains aluminum oxide (Al2O3), zirconium oxide (ZrO2), magnesium oxide (MgO), or mixtures thereof, preferably at least 80%, particularly preferably at least 90%. In particular, the transport tray can consist of aluminum oxide (Al2O3), zirconium oxide (ZrO2), magnesium oxide (MgO), or mixtures thereof.

[0034] According to an advantageous embodiment of the transport trough, the support structure contains or consists of a material selected from cordierite, mullite, a cordierite / spinel / mullite mixture, R-SiC, N-SiC, S-SiC, Si-SiC, oxide-bonded SiC, or mixtures thereof. It is also possible that the support structure contains or consists of graphite.

[0035] The transport tray according to the invention can, in principle, be used for the production of any chemical products in which the transport tray is conveyed through an oven, in particular a continuous oven, and the starting materials contained in the transport tray undergo a chemical reaction by heating in the oven. The transport tray is particularly advantageous in the production of a (lithium-ion-based) active cathode material for a lithium-ion battery.

[0036] The invention also extends to the use of the transport tray according to the invention for the production of a cathode material for a lithium-ion battery, in particular a lithium mixed metal oxide with the transition metals nickel (Nickel), manganese (Mn) and cobalt (Co), described by the general formula LiNi x Mn y Co z O2 with x+y+z = 1.

[0037] The various embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention.

[0038] The invention will now be explained in more detail using exemplary embodiments, with reference to the accompanying drawings. These show, in simplified, not-to-scale representation: Fig. 1-9 different illustrations to demonstrate a first embodiment of the transport tray according to the invention; Fig. 10-11 different views of a further embodiment of the transport tray according to the invention; Fig. 12-13 different views of a further embodiment of the transport tray according to the invention; Fig. 14-15 different views of further embodiments of the transport tray according to the invention; Fig. 16-17 different views of a further embodiment of the transport tray according to the invention; Fig. 18-19 different views of another embodiment of the transport tray according to the invention. Detailed description of the drawings

[0039] Reference will first be made to the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8 to Fig. 9, wherein a first embodiment of the transport tray according to the invention is shown in various views. Fig. Figure 1 shows the transport tray, designated with the reference number 1, in a perspective view from above. In the Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8 to Fig. Figure 9 also shows details and components of the transport tray 1. The transport tray 1 is used for transporting and heating chemical substances in an oven, for example, a continuous oven. Typically, a continuous oven includes a roller bed with actively driven rollers, which together form a transport surface for supporting and transporting the transport tray 1 from an oven inlet to an oven outlet. Since the specific construction of a continuous oven is not necessary for understanding the invention, its description is unnecessary.

[0040] The in Fig. The transport tray 1 shown comprises an outer support structure 2, which is in Fig. 2 is shown in a separate illustration. The support structure 2 is a rigid body formed in one piece. The support structure 2 consists of a base 3 and a frame 4, whereby the base 3 and frame 4 are firmly connected to each other due to the one-piece nature of the support structure 2 and cannot be separated from each other without damage. In the practical use of the transport tray 1, the base 3 typically has a horizontal orientation, and the frame 4 a vertical orientation. In the present embodiment, the frame 4 is a closed or circumferential frame. The support structure 2, consisting of the base 3 and frame 4, thus forms an outer capsule.

[0041] The base 3 typically has a flat, front (upper) surface 5 and a rear (lower) surface 6. The rear surface 6, which is also the base of the support structure 2, serves to place the transport tray 1 onto a surface. In the present embodiment, the support structure 2 has a continuous (i.e., uninterrupted and / or continuous) base 3, which here, for example, is designed as a flat plate and extends over the entire lower area of ​​the support structure 2 up to the frame 4. The continuous base 3 has no openings.

[0042] The frame 4 is essentially rectangular and can be conceptually divided into two opposing (parallel) frame sections 7 and 7', respectively, which are connected by diagonally arranged corner sections 8. In this configuration, the support structure 2 has a closed or continuous (i.e., uninterrupted) frame 4. The frame sections 7 and 7' are, for example, each flat and plate-like. Each corner section 8, which connects two adjacent frame sections 7 and 7', is arranged at an angle of 45° to the frame sections 7 and 7'. The frame 4 has an inner frame surface 9 and an outer frame surface 10.

[0043] The corner sections 8 of the frame 4 of the support structure 2 each have openings 12, which here, for example, are formed in the form of round holes. In the Fig. In the example shown, the corner sections 8 each have two openings 12, whereby a larger or smaller number of openings 12 can be provided.

[0044] The front base surface 5 and the inner frame surface 9 together define an interior area 11 (here an upwardly open tub space) of the support structure 2, which serves to accommodate elements of a lining 29 for the tub-shaped cavity 25 of the transport tub 1, which will be explained in more detail below.

[0045] Reference will now be made to the Fig. 3 and Fig. Figure 4 illustrates the insertion of various inserts into the interior 11 of the support structure 2. The inserts form the lining 29, which encloses the trough-shaped cavity 25 of the transport trough 1. Accordingly, a base plate 13 is placed on the front base surface 5, and several frame plates 14, 14' are positioned adjacent to the frame sections 7, 7' of the inner frame surface 9. In the Fig. 3 and Fig. Figure 4 illustrates the insertion process with arrows. The base plate 13 rests freely on the base 3. The frame plates 14, 14' are clamped against the frame 4, as described in more detail below. Here, the base plate 13 and the frame plates 14, 14' are each designed as flat plates without any openings. It would also be conceivable for the base plate 13 to be made up of several parts, for example, several strips.

[0046] In Fig. Figure 5 shows the transport tray 1 in an intermediate state of assembly in a perspective view from a slanted top view. Fig. Figure 5 illustrates in particular the fastening of the frame plates 14, 14' to the frame 4. Corner pieces 15 are provided for fastening the frame plates 14, 14' to the frame 4. These corner pieces 15 are placed on the edge regions 17, 17' of two immediately adjacent frame plates 14, 14' in the area of ​​the corner sections 8. The placement of the corner pieces 15 on the corner sections 8 is shown in Figure 5. Fig. 5 illustrated by arrows.

[0047] The corner pieces 15 are fastened to the frame 4 by threaded screws 16, which are inserted from the outside through the openings 12 in the corner sections 8 of the frame 4 and screwed into the corner pieces 15. For this purpose, the corner pieces 15 are provided with blind-ended (non-through) blind holes, each of which has a thread for screwing in the threaded screws 16. The blind holes and their threads are not shown in detail in the figures.

[0048] Blind holes, as described here, represent a particularly good technical solution. It would also be conceivable to provide through holes instead of blind holes (which is more cost-effective), in which case the threaded screws 16 would be secured with nuts. However, a disadvantage of this solution is that the nuts protrude into the trough-shaped cavity 25 of the transport tray 1, as they are exposed to the corrosive attack of the chemically aggressive substances. To avoid this, it would be conceivable to provide a recess for each threaded screw 16 in the corner piece 15, which would accommodate the screw 16 and its corresponding nut. Generally, it is advantageous if no components not belonging to the lining, such as the threaded screws 16, protrude into the trough-shaped cavity 25.

[0049] The frame plates 14, 14' are clamped against the inner frame surface 9 by the corner pieces 15. The base plate 13 is not attached to the base 3, but rests freely on it. However, the base plate 13 can be fixed perpendicular to the base 3 by clamping it through the frame plates 14, 14'. The fully assembled transport tray 1 is in Fig. 1 shown.

[0050] In Fig. Figure 6 shows a horizontal section (parallel to the base 3) of the fully assembled transport tray 1. A corner area of ​​the transport tray 1 is marked by the dashed circle A. The marked corner area A of the transport tray 1 of Fig. 6 is in Fig. 7 shown in a greatly enlarged view.

[0051] As in Fig. As can be seen in Figure 7, the corner piece 15 overlaps the respective edge regions 17, 17' of the adjacent frame plates 14, 14'. For this purpose, the corner piece 15 is provided on both sides with grooves 18, 18' in which the edge regions 17, 17' of the frame plates 14, 14' are received. The grooves 18, 18' each have a rib-shaped projection 19, 19' that overlaps the corresponding edge region 17, 17' of the frame plates 14, 14'.

[0052] Crucially, the edge regions 17, 17' of the frame plates 14, 14' are each accommodated with play in the corresponding groove 18, 18', i.e., they do not completely fill the grooves 18, 18'. Therefore, a free space ("clearance") exists between each edge region 17, 17' of the frame plates 14, 14' and the corner section 15 within the grooves 18, 18'. These clearances 20, 20' are formed in the circumferential direction of the frame 4 (i.e., in the plane of the frame plates 14, 14' and in the circumferential direction of the frame 4). Thus, the frame plates 14, 14' each have a clearance in at least two orthogonal directions relative to their plane, allowing for unimpeded thermal expansion of the frame plates 14, 14'. In other words, the frame plates 14, 14' are each received with sufficient clearance in the grooves 18, 18', so that thermal expansion of the frame slats 14, 14' in the plate planes is permitted.

[0053] Advantageously, the width of the clearances 20, 20' in the circumferential direction of the frame 4 is only such that thermal expansion of the frame plates 14 is possible without hindrance, but excessive soiling is prevented. Preferably, the width of the clearances 20, 20' is a maximum of 2.5 mm.

[0054] Reference will now be made to the Fig. 8 and Fig. 9 taken, whereby Fig. Figure 8 shows a sectional view of the transport tray 1 perpendicular to the plane of the floor 3 and in Fig. 9 an enlarged sectional view according to the one in Fig. 8 marked area B is shown.

[0055] Accordingly, the base plate 13 is also accommodated within the interior area 11 of the support structure 2 with clearance, leaving a circumferential gap 21 (i.e., a free space) between the base plate 13 and the frame sections 7, 7'. The base plate 13 thus has, with respect to its plane, a free space in at least two orthogonal directions (here even circumferentially), so that thermal expansion of the base plate 13 is not impeded. The thermal expansion of the base plate 13 is in Fig. Figure 8 is schematically represented by arrows. In other words, the base plate 13 is supported by the support structure 2 with sufficient clearance to allow for thermal expansion in the plane of the plate.

[0056] In the illustrated embodiment, the frame plates 14, 14' each have a width T measured perpendicular to the gap 21 (see Fig. 9), which is larger than the width of the gap 21, so that the frame plates 14, 14' cannot penetrate into the gap 21, but instead rest on the base plate 13. The width T of the frame plates 14, 14' is measured parallel to the plane of the base 3 and is the shortest dimension perpendicular through the frame plates 14, 14'. By means of the frame plates 14, 14' resting on the base plate 13, the base plate 13 can be fixed in a direction perpendicular to the base 3, whereby the thermal expansion of the base plate 13 in the plane of the plate is not affected.

[0057] The base plate 13 and the frame plates 14, 14', as well as the corner pieces 15, completely line the interior 11 of the support structure 2. This means that the base plate 13, frame plates 14, 14', and corner pieces 15 together form a complete lining 29 (i.e., wall) of a trough-shaped cavity 25 of the transport trough 1. The cavity 25 serves to hold raw materials that are to be converted into a chemical product by heating in an oven, e.g., a continuous furnace. For this purpose, the transport trough 1 is placed on the rear base surface 6 in the oven and, in particular, transported through the oven. The lining 29 can be removed from the support structure 2 without damage.

[0058] The transport tray 1 is particularly advantageous for the production of an active cathode material for a lithium-ion battery, in particular a lithium mixed metal oxide with the transition metals nickel (Nickel), manganese (Mn) and cobalt (Co), described by the general formula LiNi x Mn y Co z O2 with x+y+z = 1. However, it would also be conceivable to use transport tub 1 for the production of other substances, for example color pigments.

[0059] The transport tray 1 solves the aforementioned problems related to the required high resistance to temperature changes combined with good corrosion resistance. Advantageously, the support structure 2 and the lining 29 can be made of different materials, depending on their function. The support structure 2 is well protected from corrosion by the lining 29, so the material of the support structure 2 can be selected primarily based on its resistance to temperature changes and its strength. Corrosion resistance is of secondary importance for the support structure 2. In contrast, the inner lining 29 must be highly resistant to both corrosion and temperature changes. Corrosion resistance is achieved through the specific material selection, and temperature resistance through the structural design of the lining 29.In a particularly advantageous way, the thermal expansions of both the base plate 13 and the frame plates 14, 14' are not hindered in their respective plate planes, so that no adverse high mechanical stresses build up which could ultimately lead to the breakage of the transport tray 1.

[0060] The support structure 2 and the lining 29 of the support structure 2 are advantageously made of different materials, wherein the lining 29 is preferably made of a material which, with respect to the chemical reaction of the same product, is more corrosion-resistant than the material of the support structure 2.

[0061] The support structure 2 preferably consists of a high-strength, temperature-resistant material with a relatively small thickness and relatively low weight. Preferably, the support structure 2 contains or consists of a material selected from R-SiC, N-SiC, S-SiC, Si-SiC, oxide-bonded SiC, or mixtures thereof. The support structure 2 can also consist, for example, of cordierite, mullite, or a cordierite / spinel / mullite mixture. These are materials with high strength, low thermal expansion, and excellent temperature-resistant properties; however, in the case of SiC, they have rather low corrosion resistance. This is not detrimental, however, since the support structure 2 is well protected against corrosion by the lining 29.

[0062] The lining 29 preferably contains aluminum oxide (Al₂O₃), magnesium oxide (MgO), zirconium oxide (ZrO₂), or mixtures thereof, wherein the content of these substances is preferably at least 80%, particularly preferably at least 90%. In particular, the lining 29 can also consist of these substances. Aluminum oxide, preferably pure and ideally densely fired, is a material with particularly good corrosion resistance but rather low thermal shock resistance. These materials can be cast, pressed, or produced by plasma or foil casting processes.

[0063] Preferably the frame plates 14, 14' and / or the base plate 13 each have a relatively thin wall thickness in the range of 1.5 mm to 5 mm and are designed, for example, in the form of a foil.

[0064] Due to the excellent corrosion protection provided by the lining 29 and its construction from at least one of the aforementioned materials with good thermal shock resistance, the support structure 2 can be used very frequently. For example, the service life of the support structure 2 can exceed 1000 cycles. The inner lining 29 can be removed from the support structure 2 without damage and can therefore be easily replaced separately if it corrodes and easily reused. Since the material of the lining 29 can be specifically selected for its corrosion resistance and its thermal shock resistance is ensured by its structural design, the lining 29 can also be used for a very large number of firing cycles without needing to be replaced.

[0065] Likewise, the base plate 13 and the frame plates 14, 14' can be made of different materials, wherein the base plate 13 is advantageously made of a material that, with respect to the chemical reaction of the same product, is more corrosion-resistant than the material of the frame plates 14, 14'. Preferably, the base plate 13 contains at least 80%, and particularly preferably at least 90%, aluminum oxide (Al₂O₃), magnesium oxide (MgO), zirconium oxide (ZrO₂), or mixtures thereof. The base plate 13 can also consist of these materials.

[0066] Preferably, the frame plates 14, 14' are made of a material selected from the group consisting of aluminum oxide, zirconium oxide, magnesium oxide, R-SiC, N-SiC, S-SiC and Si-SiC, or mixtures thereof. For example, the frame plates 14, 14' can also be made of cordierite or a cordierite / spinel / mullite mixture.

[0067] It is understood that the base plate 13 and the frame plates 14, 14' can also be made of the same material, which is preferably at least 80%, particularly preferably at least 90%, aluminium oxide (Al2O3), magnesium oxide (MgO), zirconium oxide (ZrO2) or mixtures thereof.

[0068] The base plate 13 and the frame plates 14, 14', as well as the corner pieces 15, can be replaced separately. For example, the base plate 13 can be replaced separately if it is more heavily corroded than the frame plates 14, 14'. This saves costs and material. Similarly, the base plate 13 or the frame plates 14, 14' can be easily cleaned, for example, by sandblasting. It would also be conceivable to form the base plate 13 in multiple parts, for example, from strips. In this case, individual strips could also be replaced separately.

[0069] Reference will now be made to the Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15, Fig. 16, Fig. 17, Fig. 18 to Fig. Figure 19 illustrates further embodiments of the transport tray 1 according to the invention by means of various views. To avoid unnecessary repetition, only the differences from the previously described embodiment are discussed. Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8 to Fig. Section 9 is explained, and otherwise reference is made to the above statements.

[0070] First, let's consider the Fig. 10 and Fig. 11 considered. Fig. Figure 10 shows a further embodiment of the transport tub 1 in a perspective view from a slanted top view, Fig. Figure 11 shows the underside of transport tray 1.

[0071] Accordingly, the frame sections 7, 7' of the frame 4 of the support structure 2 (but not the frame plates 14, 14') are each provided with a recess 22, which here, for example, is approximately rectangular. The recesses 22 each extend over a large part (preferably at least 50%) of the area of ​​the associated frame section 7, 7'.

[0072] As in Fig. As shown in Figure 11, the base 3 of the support structure 2 (but not the base plate 13) is provided with a large number of holes 23. The cutouts 22 and the holes 23 reduce the weight of the transport tray 1. In addition, material and costs for the support structure 2 can be saved.

[0073] A further advantage arises from the improved heat transfer to the fuel. In particular, this can advantageously reduce the disadvantage of the relatively poor thermal conductivity of, for example, aluminum oxide-rich materials. For this purpose, the frame plates 14, 14' advantageously have a relatively thin wall thickness. The recesses 22 advantageously have a large area relative to the surface of the associated frame section 7, 7'. The heat can thus be transferred to the fuel without significant delay.

[0074] The recesses 22 of the frame sections 7, 7' are, for example, each completely surrounded by the material of the corresponding frame section 7, 7, i.e., the recesses 22 are each formed internally. This has the advantage that a frame web 30 is present at the opening of the trough-shaped cavity 25 of the transport trough 1, which serves as an impact edge for the frame plates 14, 14' and protects them from damage, e.g., during filling, emptying, and cleaning of the transport trough 1, and generally during any handling outside the firing process. This particularly advantageously allows the use of frame plates 14, 14' with a very thin wall thickness, which can, for example, also be designed as a film with a thin wall thickness of, e.g., 1.5 mm. Likewise, due to the low mechanical stress, frame plates 14, 14' and a base plate 13 with low strength and high porosity can be used here.These enable increased oxygen and energy transport to the fuel.

[0075] In the Fig. 12 and Fig. Figure 13 illustrates a further embodiment of the transport tub 1 according to the invention. Fig. Figure 12 shows the transport tub 1 in a perspective view from a slightly elevated angle, Fig. Figure 11 shows a (vertical) section of the transport tray 1 perpendicular to the base 3. In this embodiment of the transport tray 1, wedge-shaped corner strips 24 are provided at the transition between the frame plates 14, 14' and the base plate 13. The corner strips 24 seal the area of ​​the respective butt joint between the base plate 14 and the frame plates 14, 14', reliably and securely preventing material from entering and reaching the support structure 2. The corner strips 24 form part of the lining 29 of the transport tray 1 and thus of the tray-shaped cavity 25 of the transport tray 1. With their wedge shape, the corner strips 24 are geometrically well adapted to the transition. Advantageously, the corner strips 24 are made of the same material as the base plate 13 and the frame plates 14, 14'.Preferably, the corner strips 24 contain at least 80%, and particularly preferably at least 90%, aluminum oxide (Al2O3), magnesium oxide (MgO), zirconium oxide (ZrO2), or mixtures thereof. The corner strips 24 can also consist of these materials.

[0076] In the Fig. 14 and Fig. Figure 15 illustrates further embodiments of the transport tub 1 according to the invention. Fig. Figure 14 shows the transport tub 1 in a perspective view from a slightly elevated angle. Fig. 15 is a variant of the embodiment of Fig. 14 are shown equally in a perspective view from a slant above.

[0077] In the design of Fig. 14 are analogous to the design of Fig. 10. The frame sections 7, 7' of the frame 4 of the support structure 2 (but not the frame plates 14, 14') are each provided with a recess 22 extending over such an area that only corner pillars 26 of the frame 4 remain, to which the corner parts 15 are screwed for fastening the frame plates 14, 14'. In this configuration, the support structure 2 consists of the corner pillars 26 and the base 3, frame webs 30 as in Fig. Ten are missing. Frame 4 is therefore an open frame and consists only of the corner posts 26. Frame sections 7, 7' are largely (more than 80%) omitted. The corner posts 26 each consist of corner section 8 and a small area of ​​the adjacent frame section 7, 7'. This measure allows for significant savings in weight, material, and costs. Furthermore, heat transfer to the fuel can be improved even further.

[0078] In the exemplary embodiment of Fig. The threaded screws 16 are replaced by spring-elastic clips 27, which serve to fasten the corner pieces 15 to the corner posts 26. The clips 27 are attached to the corner pieces 15 and the corner posts 26 from above. The clips 27 are made of a ceramic material with high resistance to thermal shock. Advantageously, the clips 27 are made of specially stabilized zirconium oxide.

[0079] The clamps 27, for example, have a U-shape and can be easily attached or removed to firmly connect or disconnect the corner pieces 15 and the frame 4. The clamps 27 are typically equipped with a locking mechanism (nose) so that they remain permanently locked in a specific position, which is not shown in detail. Clamping at the four corner sections 8 ensures a permanently secure connection between the frame 4 and the frame plates 14, 14'.

[0080] In the Fig. 16 and Fig. Figure 17 illustrates a further embodiment of the transport tub 1 according to the invention, wherein Fig. 16 a sectional view perpendicular to the plane of the floor 3 is and Fig. Figure 17 shows an enlarged sectional view according to area C. This design forms the basis of Fig. 14 and Fig. 15 continued.

[0081] Accordingly, the base plate 13 extends from the area of ​​the frame plates 14, 14' to beyond them, with the frame plates 14, 14' resting on the base plate 13 over their entire width. The base plate 13 is thus larger than the area enclosed by the frame plates 14, 14' and has a projection 28 towards them. This design also offers the advantage that the thermal expansion of the base plate 13 is not impeded in its plane, while the base plate 13 is securely clamped against the ground 3. The fastening of the frame plates 14, 14' to the corner pillars 26 can be carried out as described in the Fig. 14 and Fig. 15, so that their presentation in Fig. 16 was waived.

[0082] In the Fig. 18 and Fig. Figure 19 illustrates a further embodiment of the transport tub 1 according to the invention, which demonstrates the design of Fig. 14 further training. Fig. Figure 18 shows only the support structure 2 of the transport tub 1 in a perspective view from a slanted top. Fig. Figure 19 shows the underside of the complete transport tray 1.

[0083] Accordingly, the support structure 2 consists of the base 3 and the corner pillars 26. In addition to the very large recesses 22 of the frame 4, the base 3 of the support structure 2 is provided with a large number of holes 23, for example, diamond-shaped. The holes 23 are arranged regularly, for example, in the form of a grid. This measure further reduces the weight, material, and cost of the support structure 2. The front surface 5 of the base is provided with a number of parallel support ribs 28, which serve to support the base plate 13.

[0084] From the above explanations, it follows that the invention provides an improved transport trough for the transport and heating of chemical substances. The transport trough advantageously exhibits high corrosion resistance and, at the same time, good thermal shock resistance. The good thermal shock resistance is achieved through the choice of material for the support structure and the geometric design of the lining of the trough-shaped cavity of the transport trough. High corrosion resistance can be achieved through the choice of material for the lining. The materials for the support structure and the lining can be specifically tailored to their essential functions. The lining material can advantageously be selected so that the purity or quality of the material being heated is not impaired.The transport tray can therefore be used for a large number of firing cycles, significantly more than conventional transport trays. The overall lower cost of the transport trays reduces the costs of large-scale chemical production. This is particularly true for the production of active cathode materials for lithium-ion batteries. Likewise, the amount of hazardous waste generated by corrosion-damaged transport trays can be significantly reduced. Reference symbol list 1 transport tub 2 Support structure 3 floors 4 frames 5 front floor area 6 rear floor area 7, 7' frame section 8 Corner section 9 inner frame surface 10 outer frame surface 11 Indoor area 12 13 Breakthrough in base plate 14, 14' frame plate 15 Corner piece 16 threaded screw 17, 17' Edge area 18, 18' Nut 19.19' lead 20, 20' free space 21 column 22 Exclusion 23 holes 24 Corner trim 25 cavity 26 cornerstones 27 bracket 28 support bridge 29 Lining 30 frame bridge

Claims

[1] Transport trough (1) for transporting and heating chemical substances, comprising a one-piece support structure (2) with a base (3) and a frame (4) rigidly connected thereto, wherein the frame (4) of the support structure (2) is a circumferential frame, wherein the support structure (2) supports a lining (29) of a trough-shaped cavity (25) for receiving the chemical substances, wherein the lining (29) comprises a base plate (13) resting on the base (3) and several frame plates (14, 14') clamped against the frame (4), wherein the lining (29) is supported by the support structure (2) in such a way that the thermal expansions of the base plate (13) and frame plates (14, 14') in their planes are not hindered, wherein the frame plates (14, 14') of the lining (29) are clamped to the frame (4) by clamping strips (15), wherein the clamping strips (15) each have at least one groove (18, 18') for receiving an edge region (17, 17') of an adjacent frame plate (14, 14'), wherein the edge region (17, 17') is received with play in the groove (18, 18') of the clamping strip (15), wherein the base plate (13) of the lining (29) rests freely on the base (3) of the support structure (2) and is arranged with play within the surrounding frame (4) of the support structure (2) and the other components (14, 14') of the lining (29), so that a gap (21) exists between the base plate (13) and the frame (7), wherein the frame plates (14, 14') of the lining (29) each rest on the base plate (13) of the lining (29) without penetrating the gap (21), and wherein the lining material (29) is more corrosion-resistant than the supporting structure material (2) with respect to the chemical reaction of the same product. [2] Transport tray (1) according to claim 1, wherein the circumferential frame (4) of the support structure (2) has plate-shaped frame sections (7, 7') wherein at least one plate-shaped frame section (7, 7') has at least one recess (22). [3] Transport tray (1) according to claim 2, wherein the at least one recess (22) is an internal recess. [4] Transport tray (1) according to claim 2, wherein the at least one recess (22) is a marginal recess. [5] Transport tray (1) according to one of claims 1 to 4, wherein the bottom (3) of the support structure (2) has a plurality of holes (23). [6] Transport tray (1) according to one of claims 1 to 5, which has wedge-shaped corner strips (24) for covering respective butt joints between frame plates (14, 14') and base plate (13). [7] Transport tray (1) according to any one of claims 1 to 6, wherein the support structure (2) contains a material selected from cordierite, mullite, a cordierite / spinel / mullite mixture, R-SiC, N-SiC, S-SiC, Si-SiC, oxide-bonded Si-C or mixtures thereof, and / or wherein the lining (29) contains at least 80% aluminium oxide (Al2O3), magnesium oxide (MgO), zirconium oxide (ZrO2) or mixtures thereof. [8] Use of the transport tray (1) according to any one of claims 1 to 7 for the production of a cathode material for a lithium-ion battery.

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