Process for steam cracking

Abstract

The present application relates to a method for cracking a hydrocarbon feedstock using, to the maximum extent possible, an electric power plant, wherein the electricity is obtained from a renewable source or a low-carbon source. In particular, the present invention relates to a furnace for steam cracking a hydrocarbon feedstock, wherein the furnace comprises: one or more tubes for conveying the hydrocarbon feedstock and dilution steam; and electrically heated infrared emitters for transferring heat to the tubes. The present invention also relates to a method for steam cracking a hydrocarbon feedstock using infrared radiation.

Description

[0001] introduce

[0002] The present application relates to a furnace for steam cracking a hydrocarbon feedstock and a method for steam cracking a hydrocarbon feedstock to produce olefins using maximum use of electrical power, wherein the electricity is obtained from a renewable source or a low-carbon source.

[0003] Global warming and climate change, caused by human emissions of greenhouse gases, have become a major issue of public concern. Major policy initiatives such as the Paris Climate Agreement in 2017 and the European Green Deal in 2019 require actions to reduce emissions from all sectors of society, including the chemical industry.

[0004] The chemical industry is a major source of greenhouse gas emissions, either through the generation of the energy required for its transformations through combustion, through the emission of by-products or through the end-of-life incineration of its products.

[0005] A particularly large source of greenhouse gas emissions is concentrated in several large-scale processes carried out at high temperatures (above 500°C) that require external heating by the combustion of fossil hydrocarbons. Examples are steam cracking (producing light olefins from crude oil, distillates such as naphtha or gases such as ethane, propane and butane), catalytic cracking (producing light components for fuel or feedstock use from heavy petroleum fractions) and methane steam reforming (producing hydrogen and carbon monoxide or carbon dioxide from natural gas).

[0006] Conventional steam crackers are complex industrial facilities that can be divided into three main zones, each with several types of equipment with very specific functions: (i) a hot zone, including: pyrolysis or cracking furnaces, quench exchangers and quench circuits, columns of the hot separation train; (ii) a compression zone, including: cracked gas compressors, purification and separation columns, dryers; and (iii) a cold zone, including: cold boxes, demethanizers, fractionation columns of the cold separation train, C2 and C3 converters, gasoline hydrostabilization reactors.

[0007] Conventional steam cracking is carried out in a tubular reactor in a direct fired heater (furnace). Various tube sizes and configurations can be used, such as spiral tubes, U-tubes, or straight tube layouts. Tube diameters range from 1 to 4 inches. Each furnace consists of a convection zone where waste heat is recovered and a radiant zone where pyrolysis occurs.

[0008] To reduce or even eliminate greenhouse gas emissions from these processes, using renewable or low-carbon energy sources, especially electricity, to achieve these high temperatures would be an important step forward. This is not unheard of: many examples of industrial heating with electricity are known, such as the use of electric arc furnaces to melt scrap metal or produce phosphorus, or for pipeline tracing. However, the easy availability and low cost of fossil fuels in the petrochemical industry (where they are often a side stream of certain conversions) have prevented the widespread use of electric heating technology in large facilities.

[0009] Recent emphasis on reducing greenhouse gases has led to research into such electric heating methods. US20150321912 of BASF describes a method that uses electricity as a heat source, among other things. The '912 publication relates to a method for performing a heat consumption process, wherein the total energy required for the heat consumption process on average for one year comes from at least two different energy sources, one of which is an electrical energy source, whose power varies in the range of 0 to 100% of the required total power, and three different energy modes can provide the total power required for the heat consumption process, respectively: (i) pure electrical energy, (ii) a mixture of electrical energy and at least one other non-electrical energy source, or (iii) pure non-electrical energy, wherein the conversion time from one energy mode to another energy mode does not exceed 30 minutes.

[0010] Linde (US20170130887) relates to the use of resistive electric heating for a range of high temperature processes including steam cracking. It describes a device for heating a fluid, the device comprising at least one electrically conductive pipe for containing the fluid, and at least one voltage source connected to the corresponding pipe. The voltage source is designed to generate an electric current in the connected pipe, which heats the pipe and thereby heats the fluid.

[0011] Patents EP3249027 and EP3249028 envisage that at least one tubular reactor will be heated both by using the heat of combustion generated by burning at least one fuel and by using electrical heat generated by electrical energy.

[0012] US20180243711 (Haldor Topsoe) describes the use of inductive electric heating for many high temperature processes such as steam methane reforming. It relates to a reactor system for carrying out an endothermic catalytic chemical reaction within a given temperature range when a reactant is contacted with a catalyst material. The reactor system includes a reactor unit arranged to accommodate a catalyst material, the catalyst material including one or more ferromagnetic macroscopic carriers sensitive to inductive heating, wherein the one or more ferromagnetic macroscopic carriers are ferromagnetic at a temperature up to the upper limit of a given temperature range. The one or more ferromagnetic macroscopic carriers are coated with oxides, and the oxides are doped with catalytically active particles. In addition, the reactor system includes an induction coil, which is arranged to be powered by a power supply supplying alternating current and is positioned so as to generate an alternating magnetic field in the reactor unit when energized by the power supply, thereby heating the catalyst material to a temperature within the temperature range by the alternating magnetic field.

[0013] WO2016001476 (Coolbrook) describes a shock wave reactor for thermal cracking of hydrocarbonaceous feedstocks.

[0014] Although all these documents demonstrate a strong interest in greenhouse gas-free high-temperature processes, none of these have been implemented or demonstrated on an industrial scale in steam cracking processes.

[0015] Specific instructions

[0016] The steam cracking process of hydrocarbons is one of the largest processes carried out by the European chemical industry. It is the main source of ethylene, which is the largest chemical intermediate. It is applied to feedstocks such as crude oil, naphtha or gases such as ethane, propane and butane. The total amount of ethylene exceeds 150 million tons / year, the total output of products is twice that, and greenhouse gas emissions exceed 200 million tons / year. The process consists of rapidly heating a preheated steam stream to 750°C-900°C, maintaining exposure to these temperatures for a fraction of a second, followed by rapid cooling. Part of the heat ultimately results in a high energy content of the product. The sensible and latent heat is usually recovered and used in other processes and is ultimately dissipated to the environment.

[0017] All heating steps are accomplished by the combustion of hydrocarbon gases, which are usually by-product gases that cannot be used in other ways. Heat is generated by combustion inside the furnace and transferred to the hydrocarbon substrate in the so-called firebox. The external flame heats a plurality of metal tubes essentially by radiation, while the still hot flue gases leaving the radiation zone pass through heat exchange tube bundles to preheat the feedstock and dilution steam in the convection section.

[0018] In other words: current steam crackers rely heavily on energy transfer via infrared radiation (Heynderickx, GJ et al., Banded gas and non-gray surface radiation models for high emissivity coatings, AIChE journal, 2005; Stijn Vangaever et al., Computational Fluid Dynamics-Based Study of a High Emissivity Coil Coating in an Industrial Steam Cracker, Industrial & Engineering Chemistry Research 2018 57(49), 16782-16794).

[0019] More than 90% of the heat transfer to the reactor coils in a steam cracking furnace comes from radiation. The heat flux from the furnace to the cracking coils varies between 120 and 30 kW / m2 along the length of the coils ( Scholand, Heat transfer in the radiation section of chemical tube reactors, I. Chem. E. Symposium Series, No. 78; KM Van Geem, Effect of Radial Temperature Profiles on Yields in Steam Cracking, AIChE Journal 173, January 2004, Vol. 50, p. 173).

[0020] Heat transfer via radiation occurs in the form of electromagnetic waves, primarily in the infrared region. In the context of this document, infrared radiation is defined as electromagnetic radiation with a wavelength between 700 nanometers and 1 millimeter, and is referred to as short wave, medium wave or long wave. Infrared energy propagates at the speed of light without heating the air it passes through (the amount of infrared radiation absorbed by carbon dioxide, water vapor and other particles in the air is usually negligible), and is absorbed or reflected by the objects it hits. A black body is a hypothetical object that completely absorbs all wavelengths of thermal radiation incident on it and does not reflect light (a perfect radiation emitter and absorber). When black bodies are heated to a given temperature, they emit thermal radiation. The radiated energy per unit time of a black body is proportional to the fourth power of the absolute temperature and can be expressed by the Stefan-Boltzmann Law. Perfect black bodies do not exist, but real objects are close to them, and the incident radiation (also called irradiation) is partially reflected, absorbed or transmitted. The Stefan-Boltzmann Law for non-ideal black bodies or gray bodies is:

[0021] The total power density at a radiating surface is proportional to the fourth power of the surface temperature:

[0022] P=εσT 4

[0023] in

[0024] P = heat transfer per unit time and per unit surface area (W / m 2 )

[0025] σ=5.6703 10-8(W / m 2 K 4 )-Sterfan-Boltzmann constant

[0026] T = absolute temperature (K)

[0027] A = area of ​​the emitter (m 2 )

[0028] ε = emissivity coefficient of the object (-1- for a black body)

[0029] Heat flux (W / m 2 ) can be derived from this formula.

[0030] Embodiments of the present application relate to an alternative heating method. Therefore, embodiments of the present application provide a furnace for steam cracking according to claim 1 .

[0031] Therefore, the embodiment of the present application uses an electric heating infrared emitter (or radiator). Infrared radiation is generated by any "warm" surface, and the main source can be anything that causes the temperature of the substrate to rise, from metabolic processes in the organism to external radiation from the sun. One of the mechanisms is that electric current is heated by passing a conductor, and a temperature rise is generated by resistive heating. This electric current can be generated, for example, by applying a potential difference on a conductor or by induction. The interaction of dipoles with electromagnetic fields is also a way to heat the substrate, making them the source of infrared radiation.

[0032] In fact, electrical infrared is produced by Joule heating of emitters. All emitters produce radiation that is distributed in a bell shape over the wavelength spectrum. The temperature of the emitter determines its peak wavelength: the higher the temperature of the emitter, the shorter the peak wavelength and the higher the intensity.

[0033] When radiant energy strikes an object, it can be absorbed by that object or reflected or transmitted. The amount of absorption, reflection or transmission is affected by the wavelength of the radiant energy and the physical and surface properties of the object, and only absorbed energy contributes to the heating of the product. The amount of energy absorbed by an object can be controlled by selecting the appropriate emission wavelength.

[0034] The three different wavelengths into which IR is usually divided are:

[0035] Short-wave IR, which is intense and has the greatest penetration, depending on the material being irradiated. This type of radiation is emitted over a band extending from 0.76 μm to 2.8 μm and is emitted from emitters operating at temperatures in the range of 1000°C-2200°C. Short-wave radiation sources convert up to 90% or more of the electricity they produce into infrared radiation.

[0036] - Medium wave IR, from emitters operating at temperatures in the 700°C-1000°C range, and typically peaking in the 2.3μm to 3μm range.

[0037] Long wave IR, provides the shallowest penetration of the three types, and emits at temperatures of 300° C.-700° C. Peak intensity occurs in the range extending from 3 μm to 5 μm.

[0038] There are many designs of electrical infrared emitters. The most common designs are lamps, tubes and panels (usually flat), sectors (concave or convex), or poles.

[0039] The net radiative heat transfer from one surface 1 to another surface 2 is the radiation leaving the first surface to the other surface minus the radiation arriving from the second surface, and for a gray body is equal to:

[0040] Q 1→2 =ε'σA1 F 1→2 (T1 4–T2 4 )

[0041] in

[0042] A1: The surface area of ​​the transmitter, and A2: The surface area of ​​the receiver

[0043] F 1→2 : The viewing factor from surface 1 to surface 2, where F 2→1 =(A 1 / A2)F 1→2

[0044] ε' = generalized emissivity coefficient (taking into account the material properties of the transmitter, ε1, A1, and the material properties of the receiving object, ε2, A2, and the geometric arrangement).

[0045] The light from the infrared emitter travels in straight lines and is typically emitted in all directions. Reflectors may be used to optimally focus the infrared radiation onto a receiving tube that carries the hydrocarbon feedstock and dilution steam that must be heated.

[0046] Infrared heating is well known for many domestic and industrial applications, such as heaters for outdoor patios, red hot wires in toasters, and heating elements in electric ovens. Well-known electrical infrared radiators generally take the form of resistively heated conductors of metals (including alloys), intermetallic compounds, or ceramics (including cermets), which either emit directly from their surface (compared to use in domestic electric ovens or toasters), or emit from indirectly heated ceramic materials, or emit through quartz walls. Very high temperatures can be achieved with carefully selected materials. In particular, ceramic emitters can be designed for optimal heat transfer.

[0047] The present application also provides additional embodiments according to claims 2 to 15 .

[0048] As mentioned, in an embodiment of the present application, a hydrocarbon feedstock is fed to a plurality of tubes in a furnace. These tubes are sometimes also referred to as furnace tubes or radiant furnace tubes. When in the furnace, the hydrocarbon feedstock is rapidly heated to a temperature higher than 650° C., resulting in at least a portion of the hydrocarbon feedstock being cracked to obtain olefins. The hydrocarbon feedstock leaves the furnace through the tubes, and is then rapidly cooled (quenched).

[0049] The furnace can be set up the same as a conventional combustion furnace. The present application provides that part or all of the conventional burners using fuel gas can be replaced by electrically heated infrared emitters. Since no combustion gas is produced, no convection occurs and heat recovery is not required. However, alternatively, uniform heating can be further improved by additionally applying convection by circulating an inert gas.

[0050] The electric heating infrared emitter can be a known system. An important requirement is that the electric infrared heating source is capable of heat transfer so that the hydrocarbon feedstock can be heated to a temperature of 650°C or higher, up to 750°C or even 950°C. The electric heating infrared emitter itself can have any high temperature (e.g., 1000°C to 3000°C) as long as the heat load is transferred through a combination of surface area and temperature. The electric heating infrared emitter can also emit other electromagnetic radiation (e.g., visible light) that can help transfer energy to the absorption tube (which should preferably be optimized to maximize radiation absorption).

[0051] For this temperature range, electric infrared radiation generators are known. The German company Rauschert offers ceramic heaters with element temperatures up to 1000°C. The Indian companies Kerone and Ace offer ceramic heaters with power densities up to 77kW / m2, 1kW per unit and temperatures up to 900°C. Other companies include the American companies Tempco, Watlow and Protherm. Of particular interest is the German company Bach RC, which offers silicon nitride and aluminum nitride heaters for use up to 1000°C and 150W / cm2 (1500kW / m2).

[0052] Surprisingly, in the pursuit of electrical methods of providing energy to steam crackers, no one has ever mentioned the concept of using an electrically powered infrared radiation source for the purpose of steam cracking by heating the exterior of a tube containing a hydrocarbon feedstock without producing hot combustion gases which would require recovery of the sensible heat they contain.

[0053] The embodiments of the present application replace energy sources that emit hydrocarbons, CO2, with electricity. The electricity preferably comes from renewable energy or low-carbon sources.

[0054] Renewable energy is energy from natural sources or processes that are continuously replenished on human timescales, such as sunlight, wind, rain, tides, waves, hydropower and geothermal heat.

[0055] Low-carbon energy refers to energy that comes from processes or technologies that produce electricity with significantly lower carbon dioxide emissions than conventional fossil fuel electricity generation. It includes low-carbon electricity generation sources such as wind, solar, hydroelectric, and nuclear power. The term largely excludes conventional fossil fuel sources.

[0056] The process of the present application is particularly advantageous in that the electric heat source can use electricity derived from renewable or low-carbon energy. In this case, the process results in less CO2 emissions compared to conventional steam cracking processes. A possible definition of renewable or low-carbon electricity is the amount of CO2 emitted by producing electricity. Some conventional values ​​of the amount of CO2 emitted during electricity production can be found in documents such as: Koffi, Brigitte; Cerutti, Alessandro; Duerr, Marlene; Iancu, Andreea; Kona, Albana; Janssens-Maenhout, Greet (2017): CoM Default Emission Factors for the Member States of the European Union (CoM default emission factors for EU member states) -2017 version, European Commission (European Commission), Joint Research Centre (JRC) (Joint Research Center (JRC)) [dataset]. Such files can be downloaded at the following website: http: / / data.europa.eu / 89h / jrc-com-ef-comw-ef-2017.

[0057] As a proposed definition of renewable or low carbon electricity, electricity produced with a standard emission factor of less than 0.2 tonnes CO2 / MWh of electricity is considered renewable or low carbon electricity, preferably less than 0.1 tonnes CO2 / MWh or most preferably less than 0.05 tonnes CO2 / MWh. The standard emission factor is the emissions resulting from the consumption of energy vectors using standard methods, i.e. using IPCC “standard” emission factors in accordance with IPCC principles for stationary combustion of energy vectors. For clarity, other greenhouse gases such as methane and nitrogen oxides are not taken into account in these standard emission factors. Emissions associated with the supply of energy vectors are also not taken into account in these emission factors, as they can vary significantly depending on the region and over time. For example, electricity generation from fossil resources emits the following amounts of CO2: 320-330kg CO2 / MWh emissions for the most efficient combined cycle gas turbine (CCGT) power plants; 500-520kg CO2 / MWh for modern open cycle gas turbine (OCGT) power plants; and 750-800kg CO2 / MWh for modern supercritical coal-fired power plants, while nuclear power plants, geothermal, photovoltaic, hydroelectric and wind turbines emit 0kg CO2 / MWh.

[0058] This technology also offers additional advantages over conventional heating technologies, including but not limited to:

[0059] Infrared heating can be started, shut down and adjusted in seconds, much easier than an open flame furnace.

[0060] • Electrical infrared heating allows temperature variation between tubes and over the length of the reactor tube to achieve any desired heating profile.

[0061] • Electric infrared heating completely avoids system heat losses in the form of hot flue gases, and the complicated process steps (and inevitable losses) of recovering that heat for reuse.

[0062] • Infrared heating may also allow for better furnace design, as the infrared heating system decouples the heat generation of the reactor tubes and the containment function, allowing for separate optimization.

[0063] Infrared heating systems also stay close to current furnace designs and may even allow existing assets to be modified rather than building an entirely new asset.

[0064] • The infrared heating devices can be placed around the reactor tubes in a more optimal and compact manner and thus reduce the size of the steam cracking furnace.

[0065] The feedstock for this process can be ethane, liquefied petroleum gas, naphtha or gas oil. Liquefied petroleum gas (LPG) is basically composed of propane and butane. Petroleum naphtha or naphtha is defined as a petroleum hydrocarbon fraction with a boiling point of 15°C to 200°C. It consists of a complex mixture of straight and branched paraffins (single and multi-branched), cyclic paraffins and aromatics with a carbon number ranging from 5 to about 11 carbon atoms. Light naphtha has a boiling point range of 15°C to 90°C and consists of C5 to C6 hydrocarbons, while heavy naphtha has a boiling point range of 90°C to 200°C and consists of C7 to about C11 hydrocarbons. Gas oils have a boiling point range of about 200°C to 350°C and consist of C10 to C22 hydrocarbons, essentially including linear and branched paraffins, cyclic paraffins and aromatics (including monoaromatics, naphtho-aromatics and polyaromatics). Heavier gas oils (such as atmospheric gas oil, vacuum gas oil, atmospheric residue and vacuum residue) have a boiling point range above 300°C and essentially C20+ hydrocarbons including linear and branched paraffins, cyclic paraffins and aromatics (including monoaromatics, naphtho-aromatics and polyaromatics) can be obtained from atmospheric or vacuum distillation units.

[0066] In particular, the cracking products obtained in the present process may include ethylene, propylene and benzene, and optionally hydrogen, toluene, xylene and 1,3-butadiene.

[0067] In embodiments, the outlet temperature of the reactor may be in the range of 800° C. to 1200° C., 820° C. to 1100° C., 830° C. to 950° C., 840° C. to 920° C. The outlet temperature may affect the content of high-value chemicals in the cracking products produced by the process.

[0068] In embodiments, the residence time of the feedstock through the radiant section of the reactor, where the temperature may be between 650°C and 1200°C, may be in the range of 0.005 to 0.5 seconds or 0.01 to 0.4 seconds. In some embodiments, the temperature may be greater than 750°C. In some embodiments, the temperature may be greater than 950°C.

[0069] In embodiments, the electrical heating element generates at least 20,000 W / m 2 In some embodiments, the electric heating element generates at least 40,000 W / m 2 In some embodiments, the electric heating element generates at least 50,000 W / m 2 The radiation heat flux.

[0070] In embodiments, steam cracking of the feedstock is carried out in the presence of dilution steam at a ratio of 0.1 to 1.0 kg steam / kg hydrocarbon feedstock, 0.25 to 0.7 kg steam / kg hydrocarbon feedstock or 0.35 kg steam / kg feedstock mixture to obtain cracking products as defined above.

[0071] In embodiments, the reactor outlet pressure may be in the range of 500 to 1500 mbar, 700 to 1000 mbar, or may be about 850 mbar. The residence time and temperature of the feed in the reactor should be considered together. Lower operating pressures may result in easier formation of light olefins and reduced coke formation. The lowest possible pressure may be achieved by (i) maintaining the reactor output pressure as close as possible to the atmospheric pressure at the intake of the cracked gas compressor; (ii) reducing the partial pressure of hydrocarbons by diluting with steam (which has a substantial effect on slowing down coke formation). The steam / feedstock ratio may be maintained at a level sufficient to limit coke formation.

[0072] The effluent from the pyrolysis furnace may contain unreacted feedstock, desired olefins (primarily ethylene and propylene), hydrogen, methane, a mixture of C4 (primarily isobutylene and butadiene), pyrolysis gasoline (aromatics in the C6 to C8 range), ethane, propane, diolefins (acetylene, methylacetylene, propadiene) and heavier hydrocarbons boiling in the temperature range of fuel oil (pyrolysis fuel oil). The cracked gas can be rapidly quenched to 338°C-510°C to stop the pyrolysis reaction, minimize continuous reactions and recover the sensible heat in the gas by generating high pressure steam in a parallel transfer line heat exchanger (TLE). In a plant based on gaseous feedstocks, the TLE quench gas stream can flow forward to a direct water quench tower where the gas is further cooled with recirculating cold water. In a plant based on liquid feedstocks, a pre-fractionator can be located before the water quench tower to condense and separate the fuel oil fraction from the cracked gas. In both types of plants, the main part of the heavy gasoline and dilution steam in the cracked gas can be condensed in a water quench tower at 35°C-40°C. The water-quenched gas is then compressed to about 25-35 bar in 4 or 5 stages. Between the compression stages, the condensed water and light gasoline can be removed, and the cracked gas is washed with a caustic solution or with a regenerated amine solution, followed by a caustic solution, to remove acid gases (CO2, H2S and SO2). The compressed cracked gas can be dried with a desiccant and cooled to low temperatures with propylene and ethylene refrigerants for subsequent product fractionation: pre-demethanization, pre-depropanization or pre-deethanization.

Claims

1. A method for steam cracking a hydrocarbon feedstock to produce olefins, comprising the steps of: feeding a hydrocarbon feedstock and dilution steam into one or more tubes in a furnace for steam cracking a hydrocarbon feedstock, wherein the furnace comprises: one or more tubes for conveying the hydrocarbon feedstock and the dilution steam; and electrically heated infrared emitters for transferring heat to the tubes, wherein the electric heating infrared emitter has a design selected from the group consisting of a lamp, a tube, a panel, a fan and a rod, The electric heating infrared emitter is powered by electricity produced at a standard emission factor of less than 0.2 tons of CO2 / MWh of electricity, wherein the electric heating element generates 20,000 W / m 2 or greater radiative heat flux, exposing the hydrocarbon feedstock and dilution steam in the one or more tubes to infrared radiation to crack at least a portion of the hydrocarbon feedstock, Therein, sensible or latent heat of the effluent leaving the furnace is at least partially extracted by means of one or more heat exchangers and is at least partially used to preheat the hydrocarbon feedstock, dilution steam or a mixture thereof.

2. The method according to claim 1, wherein: The electrically heated infrared emitters generate sufficient heat to heat the hydrocarbon feedstock and dilution steam to a temperature of at least 650°C in the tubes.

3. The method according to claim 1 or 2, wherein: The electrically heated infrared emitter includes one or more electrically powered heating elements.

4. The method according to claim 3, wherein: The electrical heating element is a ceramic heating element.

5. The method according to claim 3, wherein: The electrical heating element is a quartz heater comprising a heating element in a quartz tube.

6. The method according to claim 3, wherein: The electrical heating element is a metal or metal alloy heating element.

7. The method according to any one of claims 1-2 and 4-6, wherein: The electrically heated infrared emitters are arranged as an annular housing surrounding the tubes for conveying the hydrocarbon feedstock and dilution steam.

8. The method according to any one of claims 1-2 and 4-6, wherein: The electricity is produced with a standard emissions factor of less than 0.1 tonnes of CO2 / MWh of electricity.

9. The method according to claim 7, wherein: The electricity is produced with a standard emissions factor of less than 0.1 tonnes of CO2 / MWh of electricity.

10. The method according to claim 8, wherein: The electricity is produced with a standard emissions factor of less than 0.05 tonnes of CO2 / MWh of electricity.

11. The method according to claim 9, wherein: The electricity is produced with a standard emissions factor of less than 0.05 tonnes of CO2 / MWh of electricity.

12. The method according to any one of claims 1-2, 4-6 and 9-11, wherein: The one or more tubes in the cracking furnace are coated with an infrared receiving material, or wherein the one or more tubes in the cracking furnace are made of an infrared receiving material.

13. The method according to any one of claims 1-2, 4-6 and 9-11, wherein: The hydrocarbon feedstock includes one or more hydrocarbons having at least two carbon atoms.

14. The method according to claim 12, wherein: The hydrocarbon feedstock includes one or more hydrocarbons having at least two carbon atoms.

15. The method according to claim 13, wherein: The one or more hydrocarbons having at least two carbon atoms are selected from the group consisting of ethane, liquefied petroleum gas, naphtha and gas oil.

16. The method according to claim 14, wherein: The one or more hydrocarbons having at least two carbon atoms are selected from the group consisting of ethane, liquefied petroleum gas, naphtha and gas oil.

17. The method according to any one of claims 1-2, 4-6, 9-11 and 14-16, wherein The heat transfer to the hydrocarbon feedstock and the dilution steam is performed separately in at least two tubes before the two streams are mixed; or wherein the hydrocarbon feedstock and the dilution steam are mixed and heat is subsequently transferred to the mixture; or Therein, heat transfer to the hydrocarbon feedstock and the dilution steam is performed separately in at least two tubes to a temperature below 500° C., followed by mixing the two streams and further transferring heat to the mixture.