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JP-2026514496-A - Graphitization furnace including widened cross-section

JP2026514496AJP 2026514496 AJP2026514496 AJP 2026514496AJP-2026514496-A

Abstract

In a first embodiment, the disclosure relates to a graphitization furnace including a raw material inlet and a product outlet. The graphitization furnace further includes a channel 100 connecting the raw material inlet and the product outlet, the channel 100 including an upstream section 110 closer to the raw material inlet and a downstream section 120 closer to the product outlet. The upstream section 110 has a first cross section closer to the raw material inlet and a second cross section closer to the product outlet, and the downstream section 120 has a third cross section closer to the raw material inlet and a fourth cross section closer to the product outlet, where the second cross section is larger than the first cross section, and the fourth cross section is larger than the second and third cross sections.

Inventors

  • クリスティアン・シュライナー
  • ティノ・シュライナー
  • ボヤン・ヨカノヴィッチ
  • アレクサンダー・クーフナー
  • リヒャルト・ロッシャー

Assignees

  • エスジーエル・カーボン・エスイー

Dates

Publication Date
20260511
Application Date
20240426
Priority Date
20230426

Claims (15)

  1. It is a graphitization furnace, The raw material inlet and the product outlet, It includes a channel (100) connecting the raw material inlet and the product outlet, The channel (100) includes an upstream section (110) and a downstream section (120), The upstream section (110) has a first cross-section near the raw material inlet and a second cross-section near the product outlet. The downstream section (120) has a third cross-section near the raw material inlet and a fourth cross-section near the product outlet. A graphitization furnace in which the second cross-section is larger than the first cross-section, and the fourth cross-section is larger than the second and third cross-sections.
  2. The graphitization furnace according to claim 1, wherein the upstream section (110) and the downstream section (120) are spaced apart or adjacent, and in particular adjacent.
  3. The graphitization furnace according to claim 1 or 2, wherein an edge-shaped or arch-shaped transition section is provided between the upstream section (110) and the downstream section (120).
  4. The graphitization furnace is a vertical type graphitization furnace, as described in any one of claims 1 to 3.
  5. The graphitization furnace is a vertical graphitization furnace, and the downstream section (120) is located in the lower third, lower quarter, lower fifth, or lower sixth of the channel (100), more specifically, in the lower fifth or lower sixth of the channel (100), and in particular, in the lower fifth of the channel (100), where the lower part is closer to the Earth's center of gravity, according to any one of claims 1 to 4.
  6. The graphitization furnace according to any one of claims 1 to 5, wherein the channel (110) includes a heating zone, a high-temperature reaction zone, and a cooling zone, and more specifically, the downstream section (120) is disposed in the high-temperature reaction zone and/or the cooling zone, and in particular is disposed in the cooling zone.
  7. The graphitization furnace according to any one of claims 1 to 6, wherein the upstream section (110) has a first length L1, the downstream section (120) has a second length L2, the upstream section (110) and the downstream section (120) are adjacent and have a combined length L3, and the L2/L3 ratio is less than 0.5, more specifically less than 0.3, and in particular less than 0.2.
  8. The graphitization furnace according to any one of claims 1 to 7, wherein the channel (100) has a first inner diameter D1, a second inner diameter D2, a third inner diameter D3, and a fourth inner diameter D4 in the planes of the first, second, third, and fourth cross-sections, respectively, and satisfies (D2 - D1) / L1 < (D4 - D3) / L2.
  9. The graphitization furnace is a continuous-type graphitization furnace or a semi-batch-type graphitization furnace, and in particular, a continuous-type graphitization furnace, according to any one of claims 1 to 8.
  10. The graphitization furnace according to any one of claims 1 to 9, wherein the graphitization furnace is configured such that the material flow within the graphitization furnace is gravity-assisted.
  11. The graphitization furnace according to any one of claims 8 to 10, wherein the channel (100 ) has a first angle α1 determined to satisfy α1 = arctan((D2 - D1) / (2 × L1)) and a second angle α2 determined to satisfy α2 = arctan((D4 - D3) / (2 × L2)), and α1 < α2 .
  12. The graphitizing furnace according to claim 11 , wherein the second angle α2 is less than 45°, 35°, 30°, 20°, 15°, 10°, 9°, 8°, 7°, 6°, 5°, 4°, 3°, 2°, or 1°, and in particular the second angle α2 is between about 0.1° and about 45°, more specifically between about 0.2° and 20°, and in particular between about 0.3° and about 10°.
  13. The graphitizing furnace according to claim 11 or 12, wherein the second angle α2 is between about 0.1° and about 5°, more specifically between about 0.1° and about 2°, and in particular between about 0.1° and about 1.5°.
  14. The graphitization furnace according to any one of claims 1 to 13, wherein the cross-section of the upstream section (110) or downstream section (120) perpendicular to the central channel (100) axis is elliptical or polygonal, more specifically octagonal, hexagonal, rectangular, square, or elliptical, and in particular rectangular or elliptical.
  15. A method for preparing graphite from a carbonaceous material using a graphitization furnace according to any one of claims 1 to 14.

Description

This invention relates to the field of graphitization furnaces. More specifically, this invention relates to graphitization furnaces including widened cross-sections. The most commonly used anode material in lithium-ion batteries is graphite. Graphite can be lithium-ionized to the state of LiC6 , which correlates to a theoretical maximum capacity of 372 mAh/g. Artificial graphite can be produced by heating carbonaceous starting materials (e.g., coke and/or pitch) to a temperature of approximately 3000°C under the exclusion of oxygen. Heating can be carried out in a batch furnace or a continuous furnace. In a continuous furnace, the carbonaceous material is typically transported along a heated channel, and the material transforms into graphite during transport. A continuous graphitization process can be advantageous because it can produce graphite more efficiently than batch processes, enabling industrial-scale production. However, the inventors have found that some carbonaceous materials (particularly carbonaceous materials in powder form) may be prone to caking in a continuous furnace. Caking can lead to an uneven temperature distribution, which can result in reduced product quality and consistency. Furthermore, it can result in reduced process efficiency and higher production costs due to interruptions in the continuous process while resolving channel blockages induced by caking, and the need to reprocess some products that were not fully graphitized due to caking. To address the aforementioned problems, the inventors developed a graphitization furnace. This figure shows a cross-section of Channel 100, including a straight upstream section 110 and a straight downstream section 120.This figure shows a cross-section of Channel 100, which includes a straight upstream section 110 and a curved downstream section 120.This is an isometric view of the channel 100, including the straight upstream section 110, the straight downstream section 120, and the rectangular perimeter. The following provides a detailed description of this disclosure. Terms or phrases used in the description and embodiments of this disclosure are not to be constrained to have only common language or dictionary meanings, but rather to have their ordinary technical meanings as established in the relevant art, unless specifically defined otherwise in the following description. The detailed description will refer to specific embodiments to better illustrate this disclosure, but it should be understood that the presented disclosure is not limited to these specific embodiments. As described above, artificial graphite can be produced by heating carbonaceous starting materials (e.g., coke and/or pitch) to a temperature of approximately 3000°C under the exclusion of oxygen. The starting materials typically contain amorphous carbon, which is converted to graphite due to the heat. A key property of graphite is its degree of crystallinity. Higher crystallinity can result in a higher maximum specific capacity, for example, when used in batteries. The term "graphite" is well-known and has a common meaning in the art. More specifically, the term "graphite" can refer to a material containing hexagonal crystalline carbon. Alternatively or additionally, the term "graphite" can refer to a material containing at least about 60%, more specifically at least about 80%, and in particular at least about 83%, hexagonal crystalline carbon. Alternatively or additionally, the term "graphite" can refer to a material having a degree of graphitization of at least about 46%, more specifically 69%, and even more specifically at least about 80%, and in particular at least about 83%. The degree of crystallinity of graphite can be described through its degree of graphitization, which can be measured by X-ray diffraction (XRD). The crystalline carbon in graphite forms a plurality of honeycomb lattices. The distance between the plurality of honeycomb lattices is described by the parameter "interplanar distance d 002 ". XRD can be used to measure the interplanar distance d 001 between the plurality of lattices. An interplanar distance d 002 of 0.3440 nm corresponds to the interplanar distance of randomly layered graphite, and an interplanar distance of 0.3354 nm corresponds to the interplanar distance in a perfect graphite crystal. The interplane distance can be used to calculate the degree of graphitization using the following formula. Graphitization degree = (0.3440 nm - d 002 ) / (0.3440 nm - 0.3354 nm) A higher degree of graphitization allows for a higher maximum discharge capacity. The heat treatment of carbonaceous materials can be carried out in a continuous furnace (i.e., a furnace configured for the continuous or semi-continuous production of graphite). For example, the carbonaceous raw material can be transported along a channel 100 between the raw material inlet and the product outlet while being heated. The carbonaceous raw material can be in any form, for example, in