KR-20260065912-A - Direct heating electric furnace

Abstract

The steam cracking unit comprises one or more electric resistance heating tubes that are electrically connected to a current source to generate heat through electric resistance heating. Each resistance heating tube may comprise two or more tube sections. Each tube section may be supplied with current independently. A controller may be configured to coordinate the application of current to one or more tube sections to control the electric resistance heating of one or more resistance heating tubes. In examples, one or more electric heating tubes may be used as preheating tubes, cracking tubes, or both.

Inventors

• 로링, 마크, 필립
• 맥카시, 키스
• 윌리엄스, 제임스, 그래함

Assignees

• 켈로그 브라운 앤드 루트 엘엘씨

Dates

Publication Date

20260511

Application Date

20240905

Priority Date

20230908

Claims (20)

1. As a steam decomposition unit, Resistance heating tube; and A steam decomposition unit comprising a current supply device connected to the resistance heating tube—the current supply device is configured to apply current to the resistance heating tube to induce electric resistance heating.
2. In paragraph 1, The above resistance heating tube is a steam decomposition unit including a preheating tube.
3. In paragraph 2, Includes an additional warm-up section, The above preheating tube is a steam decomposition unit located at least partially within the above preheating section.
4. In paragraph 2, The above preheating tube is configured to preheat a hydrocarbon feed, a steam feed, a mixed feed stream of a hydrocarbon feed and a steam feed, or any combination thereof, in a steam cracking unit.
5. In paragraph 2, A steam decomposition unit in which the above-mentioned preheating tubes are arranged so that the feed is directed to flow through the preheating tubes before reaching the pyrolysis section.
6. In paragraph 1, The above resistance heating tube is a steam decomposition unit including a cracking tube.
7. In paragraph 6, It further includes a pyrolysis section, The cracking tube is a steam decomposition unit located at least partially within the pyrolysis section.
8. In paragraph 1, A steam decomposition unit further comprising a rectifier for providing the above current supply device.
9. In paragraph 1, A steam decomposition unit further comprising a controller for adjusting the current supply to the resistance heating tube.
10. In paragraph 1, The above resistance heating tube is a steam decomposition unit comprising a curved or curvilinear shape.
11. In paragraph 4, The above resistance heating tube is a steam decomposition unit including a U-shape.
12. In paragraph 1, The above resistance heating tube is a steam decomposition unit comprising two or more tube sections.
13. In Paragraph 12, A steam decomposition unit, wherein the first tube section is connected to the second tube section by a pipe fitting configured to electrically insulate the first tube section from the second tube section.
14. In Paragraph 13, A steam decomposition unit, wherein at least one first tube section among the above two or more tube sections is connected to the current supply device.
15. In Paragraph 14, A steam decomposition unit, wherein at least one of the two or more tube sections is connected to a second tube section of a second current supply device.
16. In paragraph 15, The current supply device connected to the first tube section is a steam decomposition unit independent of the second current supply device connected to the second tube section.
17. In Paragraph 13, The above pipe fitting is a steam decomposition unit comprising a first part and a second part configured to match.
18. In paragraph 1, A steam decomposition unit comprising one or more additional resistance heating tubes.
19. In Paragraph 18, A steam decomposition unit in which the resistance heating tube and the additional one or more resistance heating tubes are configured such that the current flowing through adjacent tubes moves in opposite directions.
20. As a steam decomposition process, A step of supplying a hydrocarbon feed to one or more resistance heating tubes of a steam cracking furnace; A step of applying current to one or more resistance heating tubes to induce electric resistance heating while the hydrocarbon feed flows through the one or more resistance heating tubes; and A steam decomposition process comprising the step of preheating the hydrocarbon feed while flowing through one or more resistance heating tubes, decomposing the hydrocarbon feed, or performing both.

Description

Direct heating electric furnace Cross-reference regarding related applications This application claims priority to U.S. provisional application No. 63/581,599 filed on September 8, 2023, which is incorporated herein by reference. Invention field The present disclosure relates to a method and process for direct heating in an electric furnace. In examples, direct heating is used in an ethylene furnace. Olefin cracking furnaces enable the production of raw materials essential for countless everyday products. These are typically large and complex pieces of equipment, requiring meticulous engineering in their design and operation to ensure efficient and safe production. Olefin cracking, also known as steam crackers or ethylene crackers, is often used to produce valuable petrochemicals such as ethylene and propylene from hydrocarbon feedstocks derived from crude oil or natural gas. Ethylene and propylene are key components of a wide range of products, including plastics, synthetic fibers, and detergents. The process occurring within an olefin cracking furnace is generally referred to as steam cracking or ethylene cracking. This process breaks down large hydrocarbon molecules into smaller hydrocarbon molecules by high-temperature thermal decomposition in the presence of steam. This process is typically carried out at temperatures ranging from 700°C to 900°C and at atmospheric pressure or slightly elevated pressure. A typical process includes the steps of preheating the hydrocarbon feed, introducing the preheated feed into a reactor, undergoing the pyrolysis reaction, and quenching and optionally separating the effluent gas. The hydrocarbon feed often consists of a mixture of light hydrocarbons, such as naphtha or liquid natural gas. When the preheated hydrocarbon feed is introduced into the cracking furnace, it is typically brought into contact with a superheated environment containing a mixture of steam or water vapor to control the reaction and prevent the formation of undesirable byproducts. The high temperature inside the furnace causes larger hydrocarbon molecules to break down through a pyrolysis process, also known as thermal cracking. As a result, smaller molecules, including ethylene and propylene, are formed, which are highly valuable in the petrochemical industry. After the cracking process, the mixture can be rapidly cooled using quenching techniques to stop further reactions. The resulting mixture contains various hydrocarbons, including the desired olefins (ethylene and propylene) as well as other byproducts. These mixtures can be sent to a separation unit that allows for the recovery of olefins produced by separating different components based on their boiling points and characteristics. An olefin cracking furnace typically comprises one or more radiating tubes through which a feed gas flows with steam to undergo pyrolysis and produce olefins. Heating must be provided to create a superheated environment to facilitate the pyrolysis process. A typical heating method is provided through one or more burners configured to burn fuel. Typical fuels used may include hydrocarbons such as methane. As such, the combustion of fuel to generate the desired heat can result in the formation of undesirable byproducts such as carbon dioxide. However, carbon emissions are harmful to the environment and often require additional processing to be captured and recycled into other products. Therefore, it is necessary to provide improved processes and systems that can reduce carbon emissions without significantly compromising production efficiency. The accompanying drawings, included to provide a further understanding of the present invention and constituting part of this specification, serve to illustrate embodiments of the present invention and explain the principles of the present invention together with the description. In the drawings, Figure 1 is an example diagram of an exemplary steam decomposition furnace having one or more electric resistance heating tubes. FIGS. 2a to 2c are diagram examples of tube sections and pipe fittings for connecting tube sections. FIG. 3 illustrates an exemplary circuit diagram for supplying current to one or more resistance heating tubes and/or tube sections. Figure 4 illustrates an example of a resistance heating tube as a coil used as a preheating tube. FIGS. 5A and 5B are exemplary diagrams of exemplary embodiments of one or more resistance heating tubes as cracking tubes within the pyrolysis section of a steam decomposition furnace. Figure 6 is a diagram example of a type of curvilinear shape that a resistance heating tube can have. In examples, processes and systems capable of eliminating one or more problems in the prior art are described. In examples, processes and systems as described herein may provide direct heating for preheating a feed and/or for providing heating for a cracking reaction. In examples, one or more electric resistance heating tubes (referred to herein as "resis