Process device for the thermal and / or chemothermal treatment of process material, and method for providing a process gas

Abstract

The invention relates to a process device for the thermal and / or chemothermal treatment of process material, comprising a housing in which a process chamber is provided, wherein the process material can be subjected to the thermal and / or chemothermal treatment in the process chamber; a conveying device by means of which the process material can be conveyed through the process chamber; a line system for conducting a process gas into the process chamber, where the process gas can be supplied to the process material; and a heating device for controlling the temperature of the process gas. According to the invention, the process gas is superheated steam, and the heating device is provided inside the process chamber. The invention also relates to a method for providing the process gas.

Description

[0001] Process device for the thermal and / or chemothermal treatment of process material and method for providing a process gas

[0002] BACKGROUND OF THE INVENTION

[0003] 1. Field of the invention

[0004] The invention relates to a process device for the thermal and / or chemothermal treatment of process material, comprising a housing in which a process chamber is arranged, wherein the process material can be subjected to thermal and / or chemothermal treatment in the process chamber by means of a process gas such as steam, and a conveying device with which the process material can be conveyed through the process chamber and a piping system for guiding the process gas into the process chamber for applying the process gas to the process material.

[0005] The invention also relates to a method for providing a process gas for the thermal and / or chemothermal treatment of process material in a process chamber of a process device for the production of anode material for batteries.

[0006] 2. Description of the state of the art

[0007] Such process equipment and methods are used on an industrial scale, for example, in industrial furnaces for the production of anode materials. For these anode materials, porous carbon material with a very high surface area and pore sizes ranging from < 2 nm to 50 nm is produced. To create this, the starting material is first carbonized in a pyrolysis process to generate an initial porous carbon framework. The process material is then heated to temperatures of 600 °C to 1300 °C in an atmosphere of superheated steam, CO₂, or O₂. During this process, the steam reacts with the carbon to form carbon monoxide and hydrogen. This reaction removes carbon from the material and creates pore structures with the desired large surface area and corresponding pore volume.

[0008] Several boundary conditions are relevant to the technical implementation of such a process. On the one hand, it is a challenge to provide a process gas, such as superheated steam, with temperatures up to 1300 °C in an energy-efficient manner within a process chamber. On the other hand, to ensure a uniform process product, it is advantageous to achieve a consistent flow pattern across the process material when exposed to the process gas.

[0009] SUMMARY OF THE INVENTION

[0010] It is an object of the invention to provide a process device and a method of the type mentioned above which enable the efficient achievement of the desired temperature of the process gas and / or enable the most uniform possible supply of the process gas to the process material.

[0011] This problem is solved by a process device according to independent claim 1.

[0012] The process device according to the invention for the thermal and / or chemothermal treatment of process material comprises a housing in which a process chamber is arranged, wherein the process material can be subjected to thermal and / or chemothermal treatment by means of a process gas in the process chamber. Furthermore, the process device comprises a conveying device with which the process material can be conveyed through the process chamber, as well as a piping system for guiding the process gas into the process chamber in order to expose the process material to the process gas.

[0013] According to the invention, the process device includes a heating device for tempering the process gas within the process chamber. The arrangement of a heating device for tempering the heating gas within the process chamber has the advantage that the temperature level of the heating gas required for the process can be generated within the process chamber. This is efficient and enables precise temperature control. At the same time, the path from the temperature increase point to the process material is short, resulting in a flow-optimized situation.

[0014] In a further development of the invention, the process chamber includes a pre-chamber in which at least one heating element is arranged for further temperature control of the process gas. Separating the heating element for further temperature control of the process gas from the actual process chamber allows the process gas to be temperature-controlled in the immediate vicinity before its application to the process material, thus improving the accuracy of the temperature control and enabling improved flow guidance.

[0015] In a particularly preferred embodiment, the pre-chamber has at least one injection wall for injecting the process gas into the process chamber. The injection wall serves several purposes. Firstly, it creates a separation between the pre-chamber and the actual process chamber, thus enabling preheating of the process gas before it flows into the process chamber via the injection wall. Furthermore, the controlled injection of the process gas allows for a controlled and / or uniform exposure of the process material to the process gas.

[0016] It is advantageous if the injection wall allows the process gas to be injected over the entire surface of the injection wall, so that the process gas can flow into the process chamber as uniformly as possible.

[0017] In this context, it is particularly advantageous if the injection wall has a large number of outlet openings to even out the flow of process gas into the process chamber. The outlet openings can be designed to ensure the process material is optimally exposed to the process gas. The distribution of the outlet openings across the surface of the injection wall can be uniform, or, to compensate for local flow imbalances, they can exhibit a corresponding increasing or decreasing density distribution across the surface.

[0018] In one embodiment, the injector wall can be at least partially ceramic, (partially) crystalline such as SiC, or made of high-alloy stainless steel such as Inconel. Ceramic materials, crystalline materials, or corresponding nickel-chromium alloy steels such as Inconel are particularly suitable for high temperatures and chemically reactive gases and enable a cost-effective and precise design of the outlet openings.

[0019] One embodiment provides that the injector wall separates the pre-chamber from the process chamber.

[0020] In a further development of the invention, the process device comprises one or more of the following temperature control devices: a steam boiler for generating steam as a process gas using the exhaust heat from a thermal afterburner; a heat exchanger for superheating the process gas using the exhaust heat from a thermal afterburner; and / or an electric flow heater for further heating the process gas, for example, for steam superheating. The temperature control devices serve to regulate the temperature of the process gas, for example, for generating or superheating steam within different temperature ranges. The steam boiler enables initial steam generation at temperatures above 100 °C. The heat exchanger for heating, for example, for steam superheating, using exhaust heat can raise the process gas—for example, steam—to temperatures between 400 °C and 600 °C.Using the electric flow heater, temperatures can be raised from 100°C to 600°C to between 500°C and 1100°C. Together with the heating device in the process chamber, temperatures between 600°C and 1300°C can ultimately be achieved.

[0021] In one embodiment of the process device, one or more temperature control devices and the heating device are preferably connected as a heating cascade, preferably in series. This enables an energy-efficient heating process, as thermal energy from the exhaust air of a thermal afterburner can be used for lower temperatures up to approximately 600 °C. Furthermore, uniform heating of the process gas can be achieved, which contributes to stabilizing the treatment process of the material. Preferably, the temperature control devices are arranged outside the process chamber. The preheated process gas can be supplied to the process chamber, and in particular to the heating device located in the pre-chamber of the process chamber, via the piping system.

[0022] The problem is also solved by a method for providing a process gas for the thermal and / or chemothermal treatment of process material in a process chamber of a process device for the production of anode material, for example for batteries.

[0023] The method according to the invention comprises the following steps: superheating the process gas by means of a heat exchanger using the exhaust heat from a thermal afterburner, superheating the process gas by means of an electric flow heater, and / or superheating the process gas by means of a heating element. At least one of these steps takes place outside the process chamber. This method allows the advantages already mentioned above in connection with the process apparatus to be achieved.

[0024] The process gas can be water vapor, CO2 and / or O2.

[0025] In an advantageous embodiment of the method, the process gas is superheated steam.

[0026] Particularly advantageous is the generation of steam as a process gas using a steam boiler from the exhaust heat of a thermal afterburner.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Exemplary embodiments of the invention are explained in more detail below with reference to the drawings. These show:

[0029] Figure 1 shows a schematic cross-sectional view of a process device,

[0030] Figure 2 shows a schematic representation of a heating cascade as well as

[0031] Figure 3 shows a flowchart of a process for the cascaded heating of steam. DESCRIPTION OF PREFERRED EXECUTION EXAMPLES

[0032] Figure 1 illustrates a schematic cross-sectional view of a process device 100 for the thermal and / or chemothermal treatment of process material. The process device 100 is designed as an activation furnace 102, i.e., process material can be subjected to activation in the activation furnace 102. During activation, the process material is exposed to a process gas for activation. For example, steam, CO2, or O2 can be used as the process gas.

[0033] The process device 100, or activation oven 102, comprises a housing 110. An inlet gate is located at the inlet of the activation oven 102, and an outlet gate at the outlet – these are not shown in Figure 1. The housing 110 essentially has the basic shape of a cuboid, the longitudinal axis of which extends substantially perpendicular to the plane of the drawing along a conveying direction. The conveying direction also runs perpendicular to the plane of the drawing.

[0034] The housing 110 can, for example, be a welded steel structure. A process chamber 112, which also extends along the conveying direction, is arranged within the housing 110 of the process device 100. The housing 110 can, for example, be lined on its inside with insulation that provides thermal shielding of the temperatures in the process chamber 112 from the environment.

[0035] The process chamber 112 is divided into a left and a right side when viewed in the direction of conveying, with the sides being symmetrically arranged. A conveying device 114 is installed in the process chamber 112, which, in the embodiment shown, comprises a pusher device 116 with a push track 118.

[0036] The process device 100, or activation furnace 102, is designed as a continuous furnace and, in terms of conveying technology, as a pusher furnace. For this purpose, the conveying system 114 comprises several hydraulic pushers (not shown). The process material to be treated is conveyed through the activation furnace 102 in support structures 120 by means of the pushers. The support structures 120 can, as shown in Figure 1, accommodate several transport troughs 122.

[0037] P 70201 WO - 7 - 08.08.2025 includes components that can be stacked on top of each other and positioned on so-called push plates 124. The push plates 124 are moved along the push track 118 and thus convey the support structures 120 along with the process material through the process chamber 112. Alternatively, the conveying technology could also be designed as a roller conveyor, for example.

[0038] For the purpose of supplying the process material with a process gas, the process device 100 has a piping system 130 for guiding the process gas into the process chamber 112 for supplying the process material with the process gas.

[0039] The piping system 130 comprises supply lines 132 for the process gas from the outside (see arrows 133) through the housing 110 into the process chamber 112 (see arrows 135). In the process chamber 112, the process gas is first injected into pre-chambers 134. The pre-chambers 134 are arranged in the process chamber 112 or directly connected to it and are separated from the interior of the process chamber 112, through which the process material is conveyed in the support structures 120, by an injection wall 136.

[0040] In the pre-chambers 134, the temperature of the injected process gas is increased by means of heating elements 138. As shown in Figure 1, the already preheated process gas (see arrows 137) flows around the heating elements 138, which have a higher temperature level and thus heat the process gas further.

[0041] After the temperature increase, the process gas is injected into the interior of the process chamber 112 via the aforementioned injection walls 136 (see arrows 139).

[0042] In the embodiment shown in Figure 1, the injection walls 136 are made of a nickel-chromium alloy steel and have a plurality of nozzles 140. A few nozzles are shown by way of example in Figure 1, designated with the reference numeral 140. The nozzles 140 are distributed over the entire surface of the injection wall 136, so that the process gas can be injected uniformly over the entire surface of the injection wall 136, in particular over the entire height of the support structures 120. This ensures, on the one hand, a uniform flow of the process gas as it enters the interior of the process chamber 112. At the same time, the flow into the interior of the process chamber 112 is concentrated on the nozzles 140 and thus occurs precisely at the designated levels where the process material – here in the transport trays 122 – is located.Furthermore, heating the process gas via the heating elements 138 in the pre-chambers 134 enables precise control of the temperature at which the process gas enters the interior of the process chamber 112. This allows the desired high temperature level to be achieved in a reproducible manner.

[0043] After flowing through the support structures 120, in particular the stacked transport trays 122, and thus after flowing over the process material stored in the transport trays 122, the process gas leaves the support structure 120 (see arrows 141) and is discharged from the process room 112 via a central outlet 142 (see arrows 143).

[0044] In the embodiment shown in Figure 1, the process gas supplied via the supply lines 132 is already at a high temperature level – for example, at a temperature between 600 °C and 1200 °C. The temperature can be further increased by a value between 30 °C and 200 °C using the heating elements 138. The temperature in the pre-chambers 134 can be determined using appropriate measuring devices 131.

[0045] The injection walls 136 can extend in one piece over the entire length and height of the pre-chamber 134 in the conveying direction. Alternatively, the injection walls 136 can also be constructed in multiple sections. The pre-chambers 134 can, for example, extend along the entire conveying path or be divided into individual pre-chambers 134 along the conveying direction. Advantageously, the pre-chambers 134 extend over the entire height of the usable interior space of the process chamber 112. For example, the area in which the conveying device 114 is located can be excluded. Alternatively, the pre-chambers 134 and the associated injection walls 136 can also be arranged only at certain sections along the conveying direction of the process device 100.

[0046] The nozzles 140 of the injection walls 136 are advantageously arranged such that, taking into account the flow pressure in the pre-chamber 134, the process material in the support structures 120 is supplied as uniformly as possible. For example, the density at the nozzles 140 or the size of the orifices of the nozzles 140 per unit area may differ in the lower region from the density / size in the upper region. For example, the density of the nozzles 140 or their orifice size per unit area may be smaller in the upper region than in the lower region, since the density varies over the height of the upper and lower regions.

[0047] P 70201 WO - 9 - 08.08.2025 Different flow conditions may result. In particular, the flow pressure and / or flow velocity may be higher in the upper region than in the lower region.

[0048] The process gas supplied to the process chamber 112 via the piping system 130 is heated by a heating cascade 200. This is shown in more detail in the schematic diagram of Figure 2. A thermal afterburner 210 combusts, for example, organic compounds produced during a process in the form of exhaust gas in a combustion chamber 212 at temperatures exceeding, for example, 800 °C. The necessary operating temperature is generated by a burner 214. The resulting purified exhaust gas 216 at high temperature is fed to a heat exchanger 218 before being released to the environment via an exhaust pipe 220 – possibly after further purification in a cleaning stage not shown.

[0049] The heating process is described below using steam as an example process gas. Alternatively, CO2 or O2 can also be used as process gases. In the latter case, the initial steam generation step is omitted in the process described below.

[0050] The waste heat extracted from the exhaust gas 216 by means of the heat exchanger 218 can be used in a first stage of the heating cascade 200 to generate steam with a temperature > 100 °C in a steam boiler 222. The steam thus produced (see arrow 224) can be fed to a heat exchanger 226, which also draws energy from the exhaust air heat of the thermal afterburner and thus raises the steam in a second stage to a higher temperature level, for example 400 to 600 °C.

[0051] The now superheated steam (see arrow 228) can be fed to an electric flow heater 230 to further increase its temperature. Using electrical energy, the electric flow heater 230 can further increase the temperature of the superheated steam 228, for example to a level between 500 °C and 1100 °C.

[0052] The superheated steam 232 is then – as indicated by reference numeral 133 in Figure 1 – fed to the process unit 100, where it passes through the O&P one last time.

[0053] P 70201 WO - 10 - 08.08.2025

[0054] Heating element 138 in the pre-chamber 134 can be heated to the ultimately desired temperature level of 600 °C to 1300 °C in front of the ceramic injection wall 136.

[0055] The upstream heating cascade 200 offers the advantage for all types of process gases that part of the heating can be achieved using waste heat from the thermal afterburner 210, thus saving energy. The subsequent superheating by means of the electric flow heater 230 and the heating element 138 ensures a uniform temperature of the process gas – in this example, water vapor – which then exhibits no or only minimal hotspots.

[0056] The series connection of several heating stages as a heating cascade 200 also enables the superheating of very large volumes of process gas, since each individual stage only needs to generate a temperature increase of a few hundred degrees Celsius. Complete superheating of the process gas solely within the process device 100, i.e., in the housing 110 or even in the process chamber 112, would not be possible with the required volume flows using a single stage.

[0057] Process unit 100 can be part of a furnace system for the production of anode material for batteries. As mentioned, process unit 100 includes the activation step of a corresponding manufacturing process, in which the previously produced carbon material is activated as process material in the process vats 122. During activation, a portion of the carbon material is oxidized, resulting in the desired pore size and pore density in the process material.

[0058] Prior to activation, the process material can be prepared by pretreating powdered starting materials and subjecting them to pyrolysis.

[0059] Subsequent processing steps after activation of the process material may include grinding into powder form, incorporating silicon into the carbon material, and passivating the process material.

[0060] Figure 3 illustrates, in a schematic flowchart, a process for the cascaded heating of a process gas using steam as an example. Other O&P

[0061] P 70201 WO - 11 - 08.08.2025

[0062] When process gases such as CO2 or O2 are used, the first step of generating the steam is eliminated.

[0063] In step S1, water is evaporated in a steam boiler, generating steam with a temperature above 100 °C. In this process, waste heat from a thermal afterburner is used via a heat exchanger to heat the water and generate the steam.

[0064] The water vapor thus generated is superheated in a further step S2 to temperatures between 400 °C and 600 °C by means of another heat exchanger, which also uses exhaust air heat from a thermal afterburner.

[0065] The already superheated steam can be further heated to an even higher temperature level between 500 °C and 1100 °C in a subsequent step S3 using an electric flow heater. Higher temperatures can be achieved with the electric flow heater than with thermal afterburning. Thermal afterburning is limited in terms of achievable temperatures due to the combustion processes involved.

[0066] The superheated steam thus generated is subjected to a final heating in the actual process chamber by means of a heating element that is surrounded by the already superheated steam (S4). Heating the steam in a pre-chamber immediately before injection (S5) into the process chamber ensures particularly uniform heating of the process gas without hotspots and thus a particularly high level of process reliability.

[0067] Overall, the cascaded heating of the process gas – in this case, steam – enables particularly energy-efficient production of the process gas due to the use of waste heat. The process gas produced in this way exhibits a particularly uniform temperature distribution without hotspots. It is possible to produce particularly large quantities of process gas because the heat input per stage is lower than with direct generation in the furnace.

Claims

O&P P 70201 WO - 12 - 08.08.2025 PATENT CLAIMS 1. Process device (100) for thermal and / or chemothermal treatment of process material, comprising a housing (110) in which a process chamber (112) is arranged, wherein the process material can be subjected to thermal and / or chemothermal treatment by means of a process gas in the process chamber (112), and a conveying device (114) with which the process material can be conveyed through the process chamber (112) and a piping system (130) for guiding the process gas into the process chamber (112) for supplying the process material with the process gas, characterized by a heating device (138) for temperature control of the process gas within the process chamber (112).

2. Process apparatus according to claim 1, wherein the process chamber (112) has a pre-chamber (134) in which at least one heating element (138) is arranged for further temperature control of the process gas.

3. Process device according to claim 2, wherein the pre-chamber (134) has at least one injection wall (136) for injecting the process gas into the process chamber (112).

4. Process device according to claim 3, wherein the injection wall (136) has a plurality of outlet openings (140) for equalizing the flow of the process gas into the process chamber (112).

5. Process device according to one of claims 3-4, wherein the injector wall (136) separates the prechamber (134) from the process chamber (112). O&P P 70201 WO - 13 - 08.08.2025 6. Process device according to one of the preceding claims, comprising one or more of the following temperature control devices (200): a) a steam boiler (222) for generating steam as process gas using the exhaust heat of a thermal afterburner (210); b) a heat exchanger (226) for superheating the process gas using the exhaust heat of a thermal afterburner (210); or / and c) an electric flow heater (230) for superheating the process gas.

7. Process device according to claim 6, wherein one or more temperature control devices (222, 226, 230) and the heating device (138) are connected to each other as a heating cascade.

8. Process device according to one of claims 6 or 7, wherein the temperature control devices (222, 226, 230) are arranged outside the process chamber (112).

9. Method for providing a process gas for the thermal and / or chemothermal treatment of process material in a process chamber of a process apparatus for the production of anode material for batteries, comprising the steps of a) superheating the process gas by means of a heat exchanger from the exhaust heat of a thermal afterburner (S2); b) superheating the process gas by means of an electric flow heater (S3); or / and c) superheating the process gas by means of a heating element (S4).

10. The method of claim 9, wherein the process gas is superheated steam.

11. The method of claim 10, comprising the step of: Generation of steam as process gas using a steam boiler from the exhaust heat of a thermal afterburner (S1); 12. Method according to any of the preceding claims, wherein at least one step (S1, S2, S3) takes place outside the process space.

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