Process for performing a pyrolysis of hydrocarbons in an indirectly heated rotary drum reactor

Abstract

A process can be used for performing a pyrolysis of hydrocarbons in a rotary drum reactor at a temperature in the range of from 600 to 1800° C. The heat for the endothermic pyrolysis is provided by resistive heating of at least one particulate electrically conductive material introduced into said rotary drum reactor and moved through the rotary drum reactor with a flow of a hydrocarbon. The rotary drum reactor contains (A) an inner wall made of electrically insulated material, (B) a pressure-bearing outer wall, and (C) an electrical heating system attached to the inner wall and/or at least one integrated electrically conducting electrode pair. The at least one electrode pair is located at both ends of the inner wall of the rotary drum.

Claims

1. -16. (canceled)

17. A process, comprising: performing an endothermic pyrolysis of at least one hydrocarbon in a rotary drum reactor at a temperature in a range of from 600 to 1800° C., wherein heat for the endothermic pyrolysis is provided by resistive heating of electrically conductive particulate material, wherein the electrically conductive particulate material is thermally stable within a range from 500 to 2000° C., and wherein the electrically conductive particulate material is introduced into said rotary drum reactor and moved through the rotary drum reactor by one or more internals attached to an inner wall of the rotary drum reactor with a parallel or countercurrent flow of the at least one hydrocarbon.

18. The process according to claim 17, wherein the electrically conductive particulate material is moved through the rotary drum reactor with a countercurrent flow of the at least one hydrocarbon, and leaves the rotary drum reactor on an opposite side.

19. The process according to claim 17, wherein the electrically conductive particulate material has a grain size of 0.5 to 10 mm.

20. The process according to claim 17, wherein a filling level of said rotary drum reactor is in a range of from 50 to 100%.

21. The process according to claim 17, wherein carbon deposits on the electrically conductive particulate material.

22. The process according to claim 17, wherein the electrically conductive particulate material is a carbonaceous material.

23. The process according to claim 22, wherein the carbonaceous material is coke, silicon carbide, and/or boron carbide.

24. The process according to claim 17, wherein the at least one hydrocarbon is methane.

25. The process according to claim 17, wherein the temperature in the rotary drum reactor is in a range of from 1000 to 1500° C.

26. The process according to claim 17, wherein electricity for the resistive heating is introduced with an electrical heating system, which can be attached to the inner wall, and/or with at least one integrated electrically conducting electrode pair, wherein each electrode of the at least one integrated electrically conducting electrode pair is located at each end of the inner wall of the rotary drum reactor.

27. The process according to claim 26, wherein the at least one integrated electrically conducting electrode pair rotates along a longitudinal axis.

28. The process according to claim 26 wherein the at least one integrated electrically conducting electrode pair is static.

29. The process according to claim 17, wherein the rotary drum reactor contains the inner wall, which is made of an electrically insulated material, and a pressurebearing outer wall, wherein both the inner wall and the outer wall rotate, and wherein the electrically insulated material of the inner wall is ceramic or a ceramic matrix composite refractory brick, and the outer wall is made of a steel alloy.

30. The process according to claim 17, wherein the rotary drum reactor contains the inner wall, which is made of an electrically insulated material, and a pressurebearing outer wall, wherein the inner wall rotates and the outer wall is static, and wherein the electrically insulated material of the inner wall is a ceramic matrix composite or a material selected from the group consisting of a steel-based alloy, a nickelbased alloy, a cobalt refractory alloy, tungsten, molybdenum, iron, and nickel: and the outer wall is made of a steel alloy.

31. The process according to claim 17, wherein an average residence time of the electrically conductive particulate material is in a range of from 10 minutes to 12 hours.

Description

[0129] Figure:

TABLE-US-00001 Description of the figures FIG. A an inner wall made of electrically insulated material FIG. B a pressure-bearing outer wall FIG. C an electrical heating system FIG. C1 an electrical heating system attached to the inner wall FIG. C2 one integrated electrically conducting electrode pair FIG. D internal(s) are attached to the inner wall of said rotating drum FIG. E electrical power supply for heating / conducting electrodes FIG. F motor FIG. 1 entrance zone FIG. 1a gas inlet FIG. 1b outlet / discharge for the particulate material FIG. 2 preheating zone FIG. 3 heated reaction zone FIG. 4a gas exit zone / gas outlet FIG. 4b feed / entrance of the particulate material

[0130] The figures show a rotating drum reactor with an electrically insulation inner wall (A) and a pressure-bearing outer drum wall (B), an electric heating systems (C, C2) and internal mixing elements (D), which are fixed at the internal wall of the drum. The rotation of the reactor, driven by a motor (F), allows a good mixing of the carbon particles and prevents agglomeration by coke deposition. Besides, the mentioned internal elements ensure the particle movement in axial direction and control the particle dwell time distribution.

[0131] The heat for endothermic pyrolysis of hydrocarbons is supplied in the reaction zone (3) or in preheating zones (2) by resistive heating of electrically conduction particles. Electricity (E) is introduced with an electrical heating system (C), which can be attached to the inner wall (C1) (see especially FIG. 2) and/or at least one integrated electrically conducting electrode pair, wherein one electrode is located at each end (both ends) of the inner wall of the rotary drum (C2) (see especially FIG. 1).

[0132] The hydrocarbon feed (1a, gas inlet) is guided in countercurrent flow to the particulate material and leaves the reactor on the other side (4a, gas outlet) in this embodiment. However, it can also be guided through the reactor in parallel to the particulate material. The particulate material is fed to the reactor (4b, feed of the particulate material), moved through the reactor and discharge on the other side (1b, discharge for the particulate material).