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EP-4737431-A2 - ENDOTHERMIC REACTIONS HEATED BY RESISTANCE HEATING

EP4737431A2EP 4737431 A2EP4737431 A2EP 4737431A2EP-4737431-A2

Abstract

The invention relates to a reactor system for carrying out an endothermic reaction of a feed gas, comprising: - a structured catalyst arranged for catalyzing said endothermic reaction of a feed gas, said structured catalyst comprising a macroscopic structure of electrically conductive material, said macroscopic structure supporting a ceramic coating, wherein said ceramic coating supports a catalytically active material; - a pressure shell housing said structured catalyst; - heat insulation layer between said structured catalyst and said pressure shell; - at least two conductors electrically connected to said electrically conductive material and to an electrical power supply placed outside said pressure shell, wherein said electrical power supply is dimensioned to heat at least part of said structured catalyst to a temperature of at least 200°C by passing an electrical current through said electrically conductive material. The invention also relates to a process for performing an endothermic reaction of a feed gas.

Inventors

  • MORTENSEN, PETER MØLGAARD
  • KLEIN, ROBERT
  • AASBERG-PETERSEN, KIM

Assignees

  • Topsoe A/S

Dates

Publication Date
20260506
Application Date
20190515

Claims (5)

  1. A reactor system for carrying out an endothermic reaction of a feed gas, said reactor system comprising: - a structured catalyst arranged for catalyzing said endothermic reaction of said feed gas, said structured catalyst comprising a catalyst material and a macroscopic structure of electrically conductive material in the form of a resistor embedded in the catalyst material, wherein the catalyst material is positioned to surround the embedded resistor; - a pressure shell housing said structured catalyst; - a heat insulation layer between said structured catalyst and said pressure shell; and - at least two conductors electrically connected to said structured catalyst and to an electrical power supply placed outside said pressure shell, wherein said electrical power supply is dimensioned to heat at least part of said structured catalyst to a temperature of at least 200°C by passing an electrical current through said electrically conductive material.
  2. A reactor system according to claim 1, wherein the embedded resistor is in a form selected from the group consisting of plates, spirals and rods.
  3. A reactor system according to any preceding claim, wherein the catalyst material comprises a combination of a catalyst support and a catalytically active material.
  4. A reactor system according to any preceding claim, wherein the embedded resistor is coated with a ceramic coating to support a catalytically active material.
  5. A reactor system according to any preceding claim, wherein the catalyst material has a form selected from the group consisting of pellets, extrudates or granulates.

Description

FIELD OF THE INVENTION Embodiments of the invention relate to a reactor system and a process for carrying out steam reforming of a feed gas comprising hydrocarbons where the heat for the endothermic reaction is provided by resistance heating. BACKGROUND Endothermic reactions will often be challenged by how efficient heat can be transferred to the reactive zone of the catalyst bed within a reactor unit. Conventional heat transfer by convection, conduction and/or radiation heating can be slow and will often meet large resistance in many configurations. This challenge can be illustrated with the tubular reformer in a steam reforming plant, which practically can be considered as a large heat exchanger with heat transfer as the rate limiting step. The temperature at the innermost part of the tubes of the tubular reformer is somewhat lower than the temperature outside the tubes due to the heat transfer rate through the walls of the tube and to the catalyst within the tubes as well as due to the endothermic nature of the steam reforming reaction. One way to supply heat within catalyst instead of outside the reactor housing the catalyst is by means of electrical resistance heating. DE102013226126 describes a process for allothermal methane reforming with physical energy reclamation, wherein methane is reformed by means of carbon dioxide to synthesis gas consisting of carbon monoxide and hydrogen. The starting gases CH4 and CO2 are conducted in a fixed bed reactor consisting of electrically conductive and catalytic particles, which is electrically heated to temperatures of about 1000 K. The conversion of the reactant gases and the generation of heat of the generated synthesis gas take place in the fixed bed reactor. It is an object of the invention to provide an alternative configuration of an electrically heated reactor system for carrying out steam reforming. It is also an object of the invention to provide a reactor system with integrated heat supply and catalysts. It is furthermore an object of the invention to provide a process for an endothermic reaction where the temperature of the endothermic reaction is controlled precisely to limit unwanted side reaction, as e.g. cracking of hydrocarbons in the dehydrogenation reactions. An advantage of the invention is that the overall emission of carbon dioxide and other emissions detrimental to the climate may be reduced considerably, in particular if the power used in the reactor system is from renewable energy resources. SUMMARY OF THE INVENTION Embodiments of the invention generally relate to a reactor system for carrying out an endothermic reaction of a feed gas, the reactor system comprising: a structured catalyst arranged for catalyzing the endothermic reaction of a feed gas, where the structured catalyst comprises a macroscopic structure of electrically conductive material, where the macroscopic structure supports a ceramic coating and wherein the ceramic coating supports a catalytically active material; a structured catalyst arranged for catalyzing said endothermic reaction of a feed gas, said structured catalyst comprising an electrically conductive material and a catalyst material;a pressure shell housing said structured catalyst;a heat insulation layer between said structured catalyst and said pressure shell;at least two conductors electrically connected to said structured catalyst and to an electrical power supply placed outside the pressure shell, wherein the electrical power supply is dimensioned to heat at least part of the structured catalyst to a temperature of at least 200°C by passing an electrical current through the electrically conductive material. The layout of the reactor system allows for feeding a pressurized feed gas to the reactor system at an inlet and directing this gas into the pressure shell of the reactor system. Inside the pressure shell, a configuration of heat insulation layers and inert material is arranged to direct the feed gas through the structured catalyst where it will be in contact with the catalyst material, where the catalytically active material will facilitate the steam reforming reaction. Additionally, the heating of the structured catalyst will supply the required heat for the endothermic reaction. The product gas from the heated structured catalyst is led to the reactor system outlet. The close proximity between the catalytically active material and the electrically conductive materials enables efficient heating of the catalytically active material by close proximity heat conduction from the resistance heated electrically conductive material. An important feature of the resistance heating process is thus that the energy is supplied inside the object itself, instead of being supplied from an external heat source via heat conduction, convection and radiation. Moreover, the hottest part of the reactor system will be within the pressure shell of the reactor system. Preferably, the electrical power supply and the structured