Electric cracking furnace system and electric cracking furnace system operation method

Abstract

The invention provides an electric cracking furnace system and an electric cracking furnace system operation method. The electric cracking furnace system comprises an electric cracking furnace, a gas replacement module, an energy storage module and a torch module; the electric cracking furnace comprises a replacement gas cavity and an electric heating cracking cavity arranged in the replacement gas cavity; a replacement gas outlet of the replacement gas module is connected with a replacement gas inlet of a replacement gas cavity of the electric cracking furnace, and a replacement gas component detection inlet of the replacement gas module is connected with a replacement gas outlet of the replacement gas cavity of the electric cracking furnace; a feed port of the torch module is connected with an electric heating cracking cavity of the electric cracking furnace, and the torch module is used for receiving materials in the electric heating cracking cavity when the electric cracking furnace has abnormal working conditions; a high-temperature medium outlet of the energy storage module is connected with an electric heating cracking cavity of the electric cracking furnace, and the energy storage module is used for providing a high-temperature medium for the electric heating cracking cavity when the torch module receives materials in the electric heating cracking cavity. The electric cracking furnace system ensures long-period stable operation of the electric cracking furnace through the gas replacement module, the energy storage module and the torch module.

Description

Technical Field

[0001] The invention belongs to the technical field of steam cracking process, and relates to an electric cracking furnace system suitable for the steam cracking process and an electric cracking furnace system operation method. Background Art

[0002] The chemical industry is a traditional high-energy consumption and high-carbon emission industry, and is one of the main sources of greenhouse gases in the industrial field. Carbon emissions from the global chemical industry account for 5.8% of the global total emissions (including 3.6% of industrial energy emissions and 2.2% of direct industrial emissions). Among them, carbon emissions caused by steam cracking account for a large proportion of carbon emissions in the chemical industry.

[0003] Traditional steam cracking furnaces generate high-temperature flue gas by mixing combustion gas with air. The high-temperature flue gas is used to preheat raw materials, generate ultra-high-pressure steam, and provide heat for cracking reactions. Figure 1As shown, it includes radiation furnace A, raw material preheating section I B, economizer section C, raw material preheating section II D, raw material and dilution steam mixing section I E, dilution steam preheating section F, high-pressure steam superheating section I G, high-pressure steam superheating section II H, raw material and dilution steam mixing section II I, desuperheater J, first quench cooler K, second quench cooler L, raw material\dilution steam mixer M, steam drum N, and air preheater R. In the process of steam cracking by using a conventional steam cracking furnace, an air stream 422 and a low-pressure steam or a rapid process water stream 425 are heat-exchanged in an air preheater R to obtain a preheated air stream 423 and a hot air low-pressure steam or a rapid process water stream 426. The preheated air stream 423 and the fuel gas stream 424 enter a radiation furnace A for combustion to generate high-temperature flue gas, which in turn provides heat energy for the raw material and dilution steam mixing section II I, the high-pressure steam superheating section II H, the high-pressure steam superheating section I G, the dilution steam preheating section F, the raw material and dilution steam mixing section I E, the raw material preheating section II D, the economizer section C, and the raw material preheating section I B; the raw material Or the decoking air and the dilution steam flow 41 enter the raw material preheating section I B for preheating to obtain the raw material flow 42 after the raw material preheating section I, the raw material flow 42 after the raw material preheating section I enters the raw material preheating section II D for preheating to obtain the raw material flow 43 after the raw material preheating section II, the total dilution steam flow 46 enters the dilution steam preheating section F for preheating to obtain the superheated dilution steam flow 47, the raw material flow 43 after the raw material preheating section II and the superheated dilution steam flow 47 enter the raw material\dilution steam mixer M for mixing to obtain the raw material\dilution mixed flow 44, the raw material\dilution mixed flow 44 enters the raw material and dilution steam mixing section I E for mixing The raw material and the diluted steam mixed section I stream 45 is obtained, the raw material and the diluted steam mixed section I stream 45 enters the raw material and the diluted steam mixed section II I for mixing to obtain the raw material and the diluted steam mixed section II stream 8, the raw material and the diluted steam mixed section II stream 48 enters the radiation furnace A, the raw material and the diluted steam mixed section II stream 48 in the radiation furnace A uses the heat energy provided by the high-temperature flue gas to undergo a cracking reaction to obtain a cracking gas stream 49, the cracking gas stream 49 enters the first quench cooler K for cooling to obtain the cracking gas stream 410 after passing through the first quench cooler, the cracking gas stream 10 after passing through the first quench cooler enters the second quench cooler Cooling is carried out in the process to obtain a cracking gas flow 411 that has passed through the second quench cooler; wherein, boiler feed water stream 413 enters the economizer section C to obtain a preheated boiler feed water stream 414, and the preheated boiler feed water stream 414 is sent to the second quench cooler L for further preheating to obtain boiler feed water stream 415, and the ultra-high pressure steam stream 416 generated by the steam drum N is sent to the high-pressure steam superheating section I G to obtain an ultra-high pressure steam stream 418, and in the desuperheater J, the ultra-high pressure steam stream 418 is mixed with the boiler feed water stream 417 to obtain an ultra-high pressure steam stream 419, and the ultra-high pressure steam stream 419 is sent to the high-pressure steam superheating section II H to obtain an ultra-high pressure steam stream 420, which is sent to the outside of the boundary area.Traditional cracking furnaces use fuel gas (methane hydrogen, liquefied gas, natural gas, etc.) mixed with air to burn and produce high-temperature flue gas as the heat source for the cracking reaction, releasing a large amount of carbon dioxide, which is contrary to the current carbon reduction needs.

[0004] In order to achieve the carbon reduction needs of the petrochemical industry, it is necessary to develop the core technology of electric cracking furnaces. In addition, the development of core technology of electric cracking furnaces can effectively promote scientific and technological innovation and further open up and expand the oil refining and ethylene industry chain. At present, electric cracking furnace technologies for steam cracking have been proposed one after another. However, the electric cracking furnace systems currently available generally have poor long-term stable operation performance and cannot meet the needs of industrial steam cracking.

[0005] In view of this, there is still a need to study an electric cracking furnace system suitable for the steam cracking process and an operating method of the electric cracking furnace system that can operate stably for a long period of time. Summary of the invention

[0006] The object of the present invention is to provide an electric cracking furnace system and an electric cracking furnace system operation method suitable for a steam cracking process that can operate stably for a long period of time. In order to achieve the above object, the present invention provides the following two technical solutions.

[0007] In a first aspect, the present invention provides an electric cracking furnace system, wherein the system comprises:

[0008] Electric cracking furnace, displacement gas module, energy storage module and flare module;

[0009] The electric cracking furnace comprises a replacement gas chamber and an electric heating cracking chamber, wherein the electric heating cracking chamber is arranged inside the replacement gas chamber (that is, the replacement gas chamber is sleeved outside the electric heating cracking chamber);

[0010] The replacement gas outlet of the replacement gas module is connected to the replacement gas inlet of the replacement gas cavity of the electric cracking furnace, and the replacement gas component detection inlet of the replacement gas module is connected to the replacement gas outlet of the replacement gas cavity of the electric cracking furnace; the replacement gas module is used to provide replacement gas to the replacement gas cavity of the electric cracking furnace and detect the components of the replacement gas discharged from the replacement gas cavity of the electric cracking furnace;

[0011] The feed port of the flare module is connected to the electric heating cracking chamber of the electric cracking furnace. The flare module is used to receive the raw materials and product gas in the electric heating cracking chamber when the electric cracking furnace has an abnormal operating condition (for example, when the electric cracking furnace is powered off, the electric heating cracking chamber leaks, etc.);

[0012] The high temperature medium outlet of the energy storage module is connected to the electric heating cracking chamber of the electric cracking furnace. The energy storage module is used to provide high temperature medium to the electric heating cracking chamber when the flare module receives the raw materials and product gas in the electric heating cracking chamber.

[0013] The electric cracking furnace system provided by the present invention uses a replacement gas module to detect the replacement gas discharged from the replacement gas chamber of the electric cracking furnace to detect whether the electric heating cracking chamber of the electric cracking furnace is leaking. If it is detected that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace has changed, it is considered that the electric heating cracking chamber of the electric cracking furnace is leaking. When the electric cracking furnace has an abnormal operating condition (including leakage of the electric heating cracking chamber, etc.), the heating function of the electric heating cracking chamber of the electric cracking furnace is shut down, and the raw materials and product gases remaining in the electric heating cracking chamber of the electric cracking furnace are transported to the flare module, and the high-temperature medium in the energy storage module is transported to the electric heating cracking chamber of the electric cracking furnace. When the electric cracking furnace is stopped normally, the amount of raw materials is gradually reduced, and steam is kept introduced, and finally switched to a hot standby state with only steam introduced, and then slowly cooled down to a safe temperature and stopped, and the flare module and the energy storage module are not enabled.

[0014] The steam cracking reaction is a strong endothermic reaction, and the fluid temperature can reach over 800°C during the cracking reaction. In a traditional steam cracking furnace, a large amount of high-temperature flue gas is generated by the combustion of fuel gas to provide the required heat for the cracking chamber in the radiation furnace. The flue gas then enters the convection section and is eventually discharged into the atmosphere through the chimney. The cracking reaction process can be monitored through the fire-watching hole for the entire radiation furnace. Due to the particularity of the heating method, the electric cracking furnace cannot directly monitor the working status of the electric heating cracking chamber. Once the electric heating cracking chamber leaks, the electric cracking furnace is prone to combustion and explosion accidents. In order to ensure the long-term stable operation of the electric cracking furnace, a replacement gas module is added to protect and monitor the electric heating cracking chamber.

[0015] The flare module receives the raw materials and product gases in the electric heating cracking chamber when abnormal operating conditions such as power failure or leakage in the electric heating cracking chamber occur in the electric cracking furnace, thereby protecting the electric cracking furnace system and ensuring the long-term stable operation of the electric cracking furnace.

[0016] When the raw materials and product gases in the electric heating cracking chamber of the electric cracking furnace are discharged into the flare module, the electric heating cracking chamber will cool down rapidly. Too fast a temperature drop will cause the electric heating cracking chamber to deform or even break. The energy storage module provides high-temperature medium to the electric heating cracking chamber, controls the cooling rate of the electric heating cracking chamber, and protects the electric heating cracking chamber under abnormal operating conditions.

[0017] According to the preferred embodiment provided in the first aspect, the electric cracking furnace system further comprises a cooling module, the electric cracking furnace is further provided with an electric heating element cooling pipe, and the cooling medium outlet of the cooling module is connected to the cooling medium inlet of the electric heating element cooling pipe of the electric cracking furnace;

[0018] Furthermore, the cooling medium recovery port of the cooling module is connected to the cooling medium outlet of the electric heating element cooling pipe of the electric cracking furnace;

[0019] Further, the cooling medium includes one of air, water, alcohol, freon, ammonia, carbon dioxide, liquid metal, liquid helium and liquid nitrogen;

[0020] In a traditional steam cracking furnace, the high-temperature flue gas generated by the combustion of fuel gas provides heat for the cracking reaction, and then enters the convection section for heat exchange and cooling to preheat the raw materials or utility logistics, and is finally discharged into the atmosphere, and the waste heat is effectively evacuated; in an electric cracking furnace, the electric heating element will generate waste heat while heating the electric heating cracking chamber. The accumulation of waste heat will cause the electric heating element to heat up and deviate from the original working temperature. The cooling module removes the waste heat generated by the electric heating element through the cooling medium to ensure the stable operation of the electric heating element.

[0021] According to the preferred embodiment provided in the first aspect, the electric cracking furnace system further comprises a preheater, a mixer, a superheater, a quenching module and a steam module;

[0022] The feed port of the preheater is used for feeding cracking raw materials, the discharge port of the preheater is connected to the feed port of the mixer, the steam outlet of the steam module is connected to the feed port of the mixer, the discharge port of the mixer is connected to the feed port of the superheater, the discharge port of the superheater is connected to the feed port of the electrically heated cracking chamber of the electric cracking furnace, and the feed port of the quenching module is connected to the discharge port of the electrically heated cracking chamber of the electric cracking furnace;

[0023] The preheater is used to preheat the cracking raw material; the mixer is used to mix the cracking raw material and steam; the superheater is used to heat the mixture of the cracking raw material and steam; the quenching module is used to quickly reduce the temperature of the cracking gas, maximize the ethylene yield in the cracking gas and recover the waste heat in the cracking gas;

[0024] Furthermore, the electric cracking furnace system further includes a decoking air module and a sewage discharge module; the discharge port of the decoking air module is connected to the feed port of the preheater, the steam outlet of the steam module is connected to the connecting pipeline between the discharge port of the decoking air module and the feed port of the preheater, and the sewage discharge module is connected to the sewage discharge port of the electrically heated cracking chamber of the electric cracking furnace;

[0025] Further, the steam module includes a dilution steam submodule and an intermediate pressure steam submodule;

[0026] The dilution steam submodule is used to provide steam at 120-300°C and 0.5-2MPa. The steam provided by the dilution steam submodule can be used to dilute the cracking feedstock (thereby reducing the hydrocarbon partial pressure to increase the yield and reducing coking in the electric cracking furnace), purge the electric cracking furnace system, and cooperate with the decoking air to decoke the electric cracking furnace system;

[0027] The medium-pressure steam submodule is used to provide steam at 300-450°C and 1.0-5.0MPa. The steam provided by the medium-pressure steam submodule can be used to purge the electric cracking furnace system and to clean the electric cracking furnace system in combination with the decoking air.

[0028] Furthermore, the quenching module can reduce the cracking gas to 150-550°C according to the needs and the type of cracking gas;

[0029] Furthermore, the steam outlet of the steam module is connected to the cooling medium inlet of the quench module, so that the steam of the steam module is used to cool the cracked gas in the quench module;

[0030] Furthermore, the cooling medium inlet of the quenching module is connected to the water outlet of the process water system, so that the process water of the process water system is used to cool the cracked gas in the quenching module;

[0031] Further, the electric cracking furnace system also includes a waste boiler module, and the cooling medium inlet and the cooling medium outlet of the quenching module are connected to the boiler feed water pipeline of the waste boiler module, so that the boiler feed water and the cracking gas are heat-exchanged in the quenching module, and the boiler feed water is used to cool the cracking gas, and the cracking gas is used to heat the boiler feed water; further, the waste boiler module can generate steam at 350-450°C; further, the electric cracking furnace system also includes a steam gradient utilization module, the steam inlet of the steam gradient utilization module is connected to the steam outlet of the waste boiler module, and the steam outlet of the steam gradient utilization module is connected to the steam supply inlet of the steam module and / or connected to the steam inlet of the steam heating pipeline of the energy storage module; in a specific embodiment, the steam outlet of the steam gradient utilization module is respectively connected to the steam supply inlet of the dilution steam submodule of the steam module, the steam supply inlet of the medium-pressure steam submodule of the steam module, and the steam inlet of the steam heating pipeline of the energy storage module;

[0032] In the above preferred embodiment, the waste boiler module is set up to realize the use of the heat of the cracking gas in the quenching module to generate steam, thereby improving the energy utilization rate and reducing the energy consumption of the electric cracking furnace system; the steam cascade utilization module is set up to realize the use of the steam generated by the waste boiler module to generate the steam required by the steam module (such as dilution steam, medium-pressure steam) and deliver it to the steam module and / or generate the steam required by the energy storage module to heat the cooling medium and deliver it to the energy storage module, so that the entire steam realizes internal circulation and reduces the energy consumption caused by the external steam;

[0033] Furthermore, the preheater is an electric preheater; further, the heating range of the electric preheater is 25-300°C;

[0034] Furthermore, the superheater is an electric superheater; further, the heating range of the electric superheater is 150-650°C;

[0035] Compared with traditional steam cracking furnaces, electric cracking furnaces lack high-temperature flue gas. The waste heat of high-temperature flue gas in traditional steam cracking furnaces is an important heat source for preheating raw materials. The electric pyrolysis furnace system lacks high-temperature flue gas and heats the raw materials by adding preheaters and superheaters with heating functions. Preheaters and superheaters with electric heating methods can be used to heat the raw materials to ensure more uniform heat distribution and higher thermal stability, improve thermal efficiency, and reduce energy consumption.

[0036] Furthermore, the mixing form adopted by the mixer may be, but is not limited to, a Venturi type, a nozzle type, a vortex type, an anisotropic pipe, etc.;

[0037] Furthermore, the electric cracking furnace system further comprises a raw material distribution module, the discharge port of the raw material distribution module is connected to the feed port of the preheater, and the raw material distribution module is used to provide cracking raw materials to the preheater according to demand; further, the cracking raw materials provided by the raw material distribution module include but are not limited to at least one of crude oil, heavy oil, diesel, liquefied gas, butane and propane;

[0038] Furthermore, the electric cracking furnace system also includes a post-separation module, the feed inlet of the post-separation module is connected to the discharge outlet of the quenching module; the post-separation module is used to separate and purify the cracking gas.

[0039] According to the preferred embodiment provided by the first aspect, the heating method of the electrically heated cracking chamber of the electric cracking furnace includes but is not limited to at least one of electromagnetic heating, resistance heating, plasma heating and kinetic energy conversion heating.

[0040] According to a preferred embodiment provided by the first aspect, the replacement gas provided by the replacement gas module to the replacement gas chamber of the electric cracking furnace includes but is not limited to at least one of nitrogen, argon and helium.

[0041] According to a preferred embodiment provided by the first aspect, the high-temperature medium provided by the energy storage module includes but is not limited to at least one of steam, nitrogen and helium.

[0042] According to a preferred embodiment provided by the first aspect, the temperature of the high-temperature medium provided by the energy storage module is 300-900°C.

[0043] According to a preferred embodiment provided by the first aspect, the energy storage module can heat the high-temperature medium by at least one of electricity, fuel gas, and high-temperature steam, but is not limited to the heating of the high-temperature medium.

[0044] In a second aspect, the present invention provides an electric cracking furnace system operation method, which is performed using the electric cracking furnace system provided by the first aspect of the present invention, and the method comprises:

[0045] In the process of using the electric cracking furnace system for steam cracking, the replacement gas module is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace in real time and to monitor the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace in real time; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace is the same as the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace, then the electric heating cracking chamber of the electric cracking furnace has not leaked; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace is different from the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace, then the electric heating cracking chamber of the electric cracking furnace has leaked, and the electric cracking furnace system is in an abnormal operating condition;

[0046] During steam cracking using an electric cracking furnace system, when the electric cracking furnace system is in an abnormal operating condition, the material supply to the electric cracking furnace is stopped, and the heating function of the electric heating cracking chamber of the electric cracking furnace is stopped, the material in the electric heating cracking chamber of the electric cracking furnace is discharged into the flare module, and at the same time, a high-temperature medium is injected into the electric heating cracking chamber of the electric cracking furnace using an energy storage module; wherein the temperature of the high-temperature medium is 300-900°C.

[0047] According to a preferred embodiment provided by the second aspect, the high temperature medium includes but is not limited to at least one of steam, nitrogen and helium.

[0048] According to a preferred embodiment provided by the second aspect, the replacement gas includes but is not limited to at least one of nitrogen, argon and helium.

[0049] According to a preferred embodiment provided in the second aspect, the method for operating the electric cracking furnace system further comprises:

[0050] In the process of steam cracking using the electric cracking furnace system, the cracking feedstock flow is preheated by a preheater to obtain a preheated cracking feedstock flow, the preheated cracking feedstock flow and the first steam flow provided by the steam module are mixed by a mixer to obtain a cracking feedstock and steam mixed flow, the cracking feedstock and steam mixed flow are preheated by a superheater to obtain a stream to be cracked, the stream to be cracked enters the electrically heated cracking gas chamber of the electric cracking furnace to undergo a steam cracking reaction to obtain a cracking gas flow, and the cracking gas flow is rapidly cooled by a quenching module to obtain a cooled cracking gas flow;

[0051] Furthermore, the electric cracking furnace system operation method further includes: in the process of using the electric cracking furnace system to perform steam cracking, the cooled cracking gas stream is separated and purified by using a post-separation module;

[0052] Further, in the process of steam cracking using the electric cracking furnace system, the first steam stream includes steam at 120-300° C. and 0.5-2 MPa provided by the dilution steam submodule in the steam module and / or steam at 200-450° C. and 1.0-5.0 MPa provided by the medium-pressure steam submodule in the steam module;

[0053] Furthermore, the operation method of the electric cracking furnace system also includes performing a decoking treatment on the electric cracking furnace system: the decoking air flow is mixed with the second steam flow provided by the steam module, and then the decoking air flow is preheated and heated in sequence by a preheater, mixed by a mixer, and preheated and heated again by a superheater to obtain a decoking flow, and the decoking flow enters the electrically heated cracking gas chamber of the electric cracking furnace to perform a coking reaction, and the product after the coking reaction is discharged into the sewage discharge module; further, in the decoking treatment of the electric cracking furnace system, the second steam flow includes 120-300°C, 0.5-2MPa steam provided by the dilution steam submodule in the steam module and / or 200-450°C, 1.0-5.0MPa steam provided by the medium-pressure steam submodule in the steam module;

[0054] Furthermore, the operation method of the electric cracking furnace system also includes purging the electric cracking furnace system: the third steam flow provided by the steam module sequentially purges the preheater, the mixer, the superheater, and the electrically heated cracking gas chamber of the electric cracking furnace, and the purged flow is discharged into the sewage discharge module;

[0055] Furthermore, the electric cracking furnace system operation method further includes using a cooling module to cool down a heating element of an electric heating cracking chamber of the electric cracking furnace through a cooling medium; further, the cooling medium includes but is not limited to one of air, water, alcohol, freon, ammonia, carbon dioxide, liquid metal, liquid helium and liquid nitrogen;

[0056] Furthermore, the electric cracking furnace system operation method further includes: in the process of using the electric cracking furnace system to perform steam cracking, using the steam module to provide a fourth steam flow as a cooling medium of the quenching module to quench the cracked gas flow entering the quenching module; further, the fourth steam flow includes 120-300° C., 0.5-2 MPa steam provided by the dilution steam submodule in the steam module and / or 200-450° C., 1.0-5.0 MPa steam provided by the medium-pressure steam submodule in the steam module;

[0057] Furthermore, the electric cracking furnace system operation method further includes: in the process of using the electric cracking furnace system to perform steam cracking, using process water provided by the process water system as a cooling medium of the quenching module to quench the cracked gas flow entering the quenching module;

[0058] Furthermore, the method for operating the electric cracking furnace system further comprises: in the process of using the electric cracking furnace system to perform steam cracking, using the boiler feed water of the waste boiler module as the cooling medium of the quenching module to quench the temperature of the cracked gas flow entering the quenching module, and re-transmitting the boiler feed water after the quenching temperature treatment of the cracked gas flow back to the waste boiler module; further, the method for operating the electric cracking furnace system further comprises: in the process of using the electric cracking furnace system to perform steam cracking, transmitting the steam generated by the waste boiler module to the steam cascade utilization module, using the steam cascade utilization module to prepare the steam required by the steam module to supply the steam module, or using the steam The steam cascade utilization module prepares steam for heating the high-temperature medium in the energy storage module, and the steam enters the energy storage module to heat the high-temperature medium; in a specific embodiment, the operation method of the electric cracking furnace system also includes: in the process of using the electric cracking furnace system to perform steam cracking, the steam generated by the waste boiler module is transported to the steam cascade utilization module, the steam required by the dilution steam submodule prepared by the steam cascade utilization module is used to replenish the dilution steam submodule, the steam required by the medium-pressure steam submodule prepared by the steam cascade utilization module is used to replenish the medium-pressure steam submodule, and the steam used by the steam cascade utilization module to heat the high-temperature medium in the energy storage module enters the energy storage module to heat the high-temperature medium;

[0059] Further, the heating temperature of the preheater is 25-300°C;

[0060] Further, the heating temperature of the superheater is 150-650°C;

[0061] Further, the quenching module reduces the cracking gas to 150-550°C;

[0062] Furthermore, the cracking feedstock includes but is not limited to at least one of crude oil, heavy oil, diesel, liquefied gas, butane and propane.

[0063] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0064] (1) The technical solution provided by the present invention utilizes a replacement gas module, an energy storage module, and a flare module to ensure the long-term stable operation of the electric cracking furnace.

[0065] (2) The technical solution provided by the present invention adopts an electric cracking furnace for steam cracking, and adopts electric heating to provide the required heat for the cracking reaction, thereby achieving near-zero carbon emissions.

[0066] (3) The technical solution provided by the present invention has a simple process and is easy to implement.

[0067] (4) The preferred solution of the technical solution provided by the present invention adopts a waste boiler module and a steam cascade utilization module to cool the cracking gas, recover the heat of the cracking gas, and provide steam supply to the steam module, thereby reducing the energy consumption of the electric cracking furnace system. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 Schematic diagram of the structure of a traditional steam cracking furnace.

[0069] Figure 2 This is a schematic diagram of the structure of the electric cracking furnace system provided in Example 1 of the present invention.

[0070] Figure 3 This is a schematic diagram of the structure of the electric cracking furnace system provided in Example 2 of the present invention.

[0071] Figure 4 This is a schematic structural diagram of the electric cracking furnace system provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0072] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0073] Example 1

[0074] This embodiment provides an electric cracking furnace system, such as Figure 2 As shown, the system includes a raw material distribution module 1, a steam module 2, a decoking air module 3, a preheater 4, a mixer 5, a superheater 6, an electric cracking furnace 7, a replacement gas module 8, an energy storage module 9, a flare module 10, a cooling module 11, a sewage discharge module 12, a quenching module 13 and a post-separation module 14.

[0075] The electric cracking furnace 7 includes a replacement gas chamber and an electric heating cracking chamber. The electric heating cracking chamber is arranged inside the replacement gas chamber (that is, the replacement gas chamber is sleeved outside the electric heating cracking chamber). The electric cracking furnace 7 is provided with an electric heating element cooling tube; the steam module 2 includes a dilution steam submodule 15 and a medium-pressure steam submodule 16. The steam outlet of the dilution steam submodule 15 is connected to the steam outlet of the medium-pressure steam submodule 16 and serves as the steam outlet of the steam module 2.

[0076] The discharge port of the raw material distribution module 1 is connected to the feed port of the preheater 4, the discharge port of the preheater 4 is connected to the feed port of the mixer 5, the steam outlet of the steam module 2 is connected to the feed port of the mixer 5, the discharge port of the mixer 5 is connected to the feed port of the superheater 6, the discharge port of the superheater 6 is connected to the feed port of the electrically heated cracking chamber of the electric cracking furnace 7, the feed port of the quenching module 13 is connected to the discharge port of the electrically heated cracking chamber of the electric cracking furnace 7, the replacement gas outlet of the replacement gas module 8 is connected to the replacement gas inlet of the replacement gas chamber of the electric cracking furnace 7, the replacement gas component detection inlet of the replacement gas module 8 is connected to the replacement gas outlet of the replacement gas chamber of the electric cracking furnace 7, the feed port of the flare module 10 is connected to the electrically heated cracking chamber of the electric cracking furnace 7, the high temperature medium outlet of the energy storage module 9 is connected to the electrically heated cracking chamber of the electric cracking furnace 7, and the cooling module 13 is connected to the discharge port of the electrically heated cracking chamber of the electric cracking furnace 7. The cooling medium outlet of the cooling module 11 is connected to the cooling medium inlet of the electric heating element cooling pipe of the electric cracking furnace 7, the discharge port of the decoking air module 3 is connected to the feed port of the preheater 4, the steam outlet of the steam module 2 is connected to the connecting pipeline between the discharge port of the decoking air module 3 and the feed port of the preheater 4, the sewage discharge module 12 is connected to the sewage discharge port of the electric heating cracking chamber of the electric cracking furnace 7, the steam outlet of the steam module 2 is connected to the cooling medium inlet of the quenching module 13, so as to utilize the steam of the steam module 2 to cool the cracking gas in the quenching module 13, the cooling medium inlet of the quenching module 13 is connected to the water outlet of the process water system 17, so as to utilize the process water of the process water system 17 to cool the cracking gas in the quenching module 13, and the feed port of the post-separation module 14 is connected to the discharge port of the quenching module 13.

[0077] The raw material distribution module 1 is used to provide cracking raw materials to the preheater according to demand; the preheater 4 is used to preheat the cracking raw materials; the mixer 5 is used to mix the cracking raw materials and steam; the superheater 6 is used to heat the mixture of the cracking raw materials and steam; the quenching module 13 is used to quickly reduce the temperature of the cracking gas, maximize the ethylene yield in the cracking gas and recover the waste heat in the cracking gas; the replacement gas module 8 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 7 and detect the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 7; the flare module 10 is used to receive the raw materials and product gas in the electric heating cracking chamber when the electric cracking furnace 7 has an abnormal operating condition (for example, the electric cracking furnace 7 is powered off, the electric heating cracking chamber leaks, etc.); the energy storage module 9 is used to provide high-temperature medium to the electric heating cracking chamber when the flare module 10 receives the raw materials and product gas in the electric heating cracking chamber; the post-separation module 14 is used to separate and purify the cracking gas.

[0078] The dilution steam submodule 15 is used to provide steam at 120-300°C and 0.5-2MPa. The steam provided by the dilution steam submodule 15 can be used to dilute cracking raw materials, purge the electric cracking furnace system, and cooperate with the decoking air to decoke the electric cracking furnace system.

[0079] The medium-pressure steam submodule 16 is used to provide steam at 300-450°C and 1.0-5.0MPa. The steam provided by the medium-pressure steam submodule can be used to purge the electric cracking furnace system and to clean the electric cracking furnace system in combination with the decoking air.

[0080] The quenching module 13 can reduce the temperature of the cracked gas to 150-550° C. according to the needs and the type of cracked gas.

[0081] The preheater 4 is an electric preheater, and the heating range of the electric preheater is 25-300°C.

[0082] The superheater 6 is an electric superheater, and the heating range of the electric superheater is 150-650°C.

[0083] The temperature of the high-temperature medium provided by the energy storage module 9 is 300-900°C.

[0084] The mixer 5 adopts a Venturi mixing type.

[0085] The cracking raw materials provided by the raw material distribution module 1 include, but are not limited to, crude oil, heavy oil, diesel, liquefied gas, butane and propane.

[0086] The heating method of the electric heating cracking chamber of the electric cracking furnace 7 is electromagnetic heating.

[0087] The cooling medium of the cooling module 11 includes, but is not limited to, one of air, water, alcohol, Freon, ammonia, carbon dioxide, liquid metal, liquid helium and liquid nitrogen.

[0088] The replacement gas provided by the replacement gas module 8 to the replacement gas chamber of the electric cracking furnace includes but is not limited to at least one of nitrogen, argon and helium.

[0089] The high-temperature medium provided by the energy storage module 9 includes but is not limited to at least one of steam, nitrogen and helium.

[0090] The energy storage module 9 heats the high-temperature medium by means of resistance heating and heat recovery.

[0091] This embodiment also provides an operation mode of an electric cracking furnace system. Using the electric cracking furnace system provided by this embodiment, the method includes:

[0092] The electric cracking furnace system is purged: the third steam flow provided by the steam module 2 is used to sequentially purge the electric heating cracking gas chambers of the preheater 4, the mixer 5, the superheater 6, and the electric cracking furnace 7, and the purged flow is discharged into the sewage discharge module 12; wherein the third steam flow is obtained by mixing the steam of 800-2000 kg / h, 185°C, and 1.5 MPa provided by the dilution steam submodule 15 and the steam of 400-1500 kg / h, 300°C, and 1.35 MPa provided by the medium-pressure steam submodule;

[0093] Steam cracking is performed using an electric cracking furnace system: a 4000 kg / h cracking raw material flow is provided through a raw material distribution module 1, and naphtha is selected as the cracking raw material; the cracking raw material flow is preheated to 210°C by a preheater 4 to obtain a preheated cracking raw material flow; a dilution steam submodule 15 provides a first steam flow of 2000 kg / h, 185°C, and 1.5 MPa; the preheated cracking raw material flow and the first steam flow are mixed by a mixer 5 to obtain a cracking raw material and steam mixed flow; the cracking raw material and steam mixed flow are preheated to 540°C by a superheater 6 to obtain a flow to be cracked; the flow to be cracked enters A steam cracking reaction is carried out at 850° C. in the electrically heated cracking gas chamber of the electric cracking furnace 7 to obtain a cracking gas flow; the cracking gas flow is rapidly cooled to 350° C. by a quenching module 13 to obtain a cooled cracking gas flow, wherein the fourth steam flow provided by the steam module 2 and the process water provided by the process water system are respectively used as cooling media of the quenching module 13 to rapidly cool the cracking gas flow entering the quenching module 13, and the fourth steam flow is 4800 kg / h, 180° C., and 0.8 MPa steam provided by the dilution steam submodule 15; the cooled cracking gas flow is separated and purified by a post-separation module 14;

[0094] The electric cracking furnace system is subjected to a decoking treatment: the 800 kg / h decoking air flow provided by the decoking air module 3 is mixed with the second steam flow provided by the steam module 2, and then preheated to 300° C. by the preheater 4, mixed by the mixer 5, and preheated to 550° C. by the superheater 6 to obtain a decoking flow, wherein the second steam flow is 2700 kg / h, 180° C., and 0.8 MPa steam provided by the dilution steam submodule 15; the decoking flow enters the electrically heated cracking gas chamber of the electric cracking furnace 7 for a coking reaction, and the product after the coking reaction is discharged into the sewage discharge module 12;

[0095] During the process of using the electric cracking furnace system for steam cracking and decoking the electric cracking furnace system, the cooling module 11 is used to cool down the heating element of the electric heating cracking chamber of the electric cracking furnace 7 through a cooling medium; wherein the cooling medium is selected from process water;

[0096] During steam cracking using the electric cracking furnace system, the replacement gas module 8 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 7 in real time and monitor the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 7 in real time; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 7 is the same as the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace 7, then the electric heating cracking chamber of the electric cracking furnace 7 has not leaked; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 7 is different from the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace 7, then the electric heating cracking chamber of the electric cracking furnace 7 has leaked, and the electric cracking furnace system is in an abnormal operating condition; wherein, nitrogen is selected as the replacement gas;

[0097] During the process of using the electric cracking furnace system for steam cracking, when the electric cracking furnace system is in an abnormal operating condition, the material supply to the electric cracking furnace 7 is stopped, and the heating function of the electric heating cracking chamber of the electric cracking furnace 7 is stopped, the material in the electric heating cracking chamber of the electric cracking furnace 7 is discharged into the flare module 10, and at the same time, the energy storage module 9 is used to inject a high-temperature medium into the electric heating cracking chamber of the electric cracking furnace 7; wherein the high-temperature medium is medium-pressure steam with a temperature of 300°C.

[0098] In this embodiment, during the operation of the electric cracking furnace system, after the electric cracking furnace 7 reaches the final operating conditions (the tube wall temperature of the electric cracking furnace 7 is within 1100-1115°C, and the absolute pressure ratio of the venturi tube is 0.9), the electric cracking furnace system performs a decoking process to remove the coke layer in the tube of the electric cracking furnace 7. The operating cycle after decoking is 60-80 days. By switching between the two operating modes of normal operation and decoking, the long-term operation of the electric cracking furnace system is ensured.

[0099] When the electrolytic furnace system lacking the replacement gas module 8 and the energy storage module 9 encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 7 is urgently shut down, and the furnace tube of the electric cracking furnace 7 will be broken and need to be replaced. However, when the electrolytic furnace system in this embodiment encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 7 is urgently shut down, and the furnace tube of the electric cracking furnace 7 will not be damaged and can continue to be used. The electric cracking furnace system in this embodiment can effectively ensure that the furnace tube of the electric cracking furnace 7 is not damaged after the heating function is urgently shut down when encountering an abnormal operating condition, thereby improving the service life of the furnace tube of the electric cracking furnace 7, and further improving the long-term stable operation performance of the electric cracking furnace system.

[0100] Example 2

[0101] This embodiment provides an electric cracking furnace system, such as Figure 3As shown, the system includes a raw material distribution module 21, a steam module 22, a decoking air module 23, a preheater 24, a mixer 25, a superheater 26, an electric cracking furnace 27, a replacement gas module 28, an energy storage module 29, a flare module 210, a cooling module 211, a sewage discharge module 212, a quenching module 213, a post-separation module 214 and a waste boiler module 217.

[0102] The electric cracking furnace 27 includes a replacement gas chamber and an electric heating cracking chamber. The electric heating cracking chamber is arranged inside the replacement gas chamber (that is, the replacement gas chamber is arranged outside the electric heating cracking chamber). The electric cracking furnace 27 is provided with an electric heating element cooling tube; the steam module 22 includes a dilution steam submodule 215 and a medium-pressure steam submodule 216. The steam outlet of the dilution steam submodule 215 is connected to the steam outlet of the medium-pressure steam submodule 216 and serves as the steam outlet of the steam module 22.

[0103] The discharge port of the raw material distribution module 21 is connected to the feed port of the preheater 24, the discharge port of the preheater 24 is connected to the feed port of the mixer 25, the steam outlet of the steam module 22 is connected to the feed port of the mixer 25, the discharge port of the mixer 25 is connected to the feed port of the superheater 26, the discharge port of the superheater 26 is connected to the feed port of the electrically heated cracking chamber of the electric cracking furnace 27, the feed port of the quenching module 213 is connected to the discharge port of the electrically heated cracking chamber of the electric cracking furnace 27, the replacement gas outlet of the replacement gas module 28 is connected to the replacement gas inlet of the replacement gas chamber of the electric cracking furnace 27, the replacement gas component detection inlet of the replacement gas module 28 is connected to the replacement gas outlet of the replacement gas chamber of the electric cracking furnace 27, the feed port of the flare module 210 is connected to the electrically heated cracking chamber of the electric cracking furnace 27, and the high temperature medium outlet of the energy storage module 29 is connected to the electric heating medium outlet of ... The electric heating cracking chamber of the cracking furnace 27 is connected, the cooling medium outlet of the cooling module 211 is connected to the cooling medium inlet of the electric heating element cooling pipe of the electric cracking furnace 27, the discharge port of the decoking air module 23 is connected to the feed port of the preheater 24, the steam outlet of the steam module 22 is connected to the connecting pipeline between the discharge port of the decoking air module 23 and the feed port of the preheater 24, the sewage discharge module 212 is connected to the sewage discharge port of the electric heating cracking chamber of the electric cracking furnace 27, the feed port of the rear separation module 214 is connected to the discharge port of the quenching module 213, the cooling medium inlet and the cooling medium outlet of the quenching module 213 are both connected to the boiler feed water pipeline of the waste boiler module 217, so as to realize heat exchange between the boiler feed water and the cracking gas in the quenching module 213, and the boiler feed water is used to cool the cracking gas, and the cracking gas is used to heat the boiler feed water.

[0104] The raw material distribution module 21 is used to provide cracking raw materials to the preheater according to demand; the preheater 24 is used to preheat the cracking raw materials; the mixer 25 is used to mix the cracking raw materials and steam; the superheater 26 is used to heat the mixture of the cracking raw materials and steam; the quenching module 213 is used to quickly reduce the temperature of the cracking gas, maximize the ethylene yield in the cracking gas and recover the waste heat in the cracking gas; the replacement gas module 28 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 27 and detect the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 27; the torch module 210 is used to receive the raw materials and product gas in the electric heating cracking chamber when the electric cracking furnace 27 has an abnormal operating condition (for example, the electric cracking furnace 27 is powered off, the electric heating cracking chamber leaks, etc.); the energy storage module 29 is used to provide high-temperature medium to the electric heating cracking chamber when the flare module 210 receives the raw materials and product gas in the electric heating cracking chamber; the post-separation module 214 is used to separate and purify the cracking gas.

[0105] The dilution steam submodule 215 is used to provide steam at 120-300°C and 0.5-2MPa. The steam provided by the dilution steam submodule 215 can be used to dilute cracking raw materials, purge the electric cracking furnace system, and cooperate with the decoking air to decoke the electric cracking furnace system.

[0106] The medium-pressure steam submodule 216 is used to provide steam at 200-450°C and 1.0-5.0MPa. The steam provided by the medium-pressure steam submodule can be used to purge the electric cracking furnace system and to clean the electric cracking furnace system in combination with the decoking air.

[0107] The quenching module 213 can reduce the temperature of the cracked gas to 150-550° C. according to the needs and the type of cracked gas.

[0108] The preheater 24 is an electric preheater, and the heating range of the electric preheater is 25-300°C.

[0109] The superheater 26 is an electric superheater, and the heating range of the electric superheater is 150-650°C.

[0110] The temperature of the high-temperature medium provided by the energy storage module 29 is 300-900°C.

[0111] The mixer 25 adopts a Venturi mixing type.

[0112] The cracking feedstock provided by the feedstock distribution module 21 includes, but is not limited to, crude oil, heavy oil, diesel, liquefied gas, butane and propane.

[0113] The heating method of the electric heating cracking chamber of the electric cracking furnace 27 is resistance heating.

[0114] The cooling medium of the cooling module 211 includes, but is not limited to, one of air, water, alcohol, Freon, ammonia, carbon dioxide, liquid metal, liquid helium and liquid nitrogen.

[0115] The replacement gas provided by the replacement gas module 28 to the replacement gas chamber of the electric cracking furnace includes, but is not limited to, at least one of nitrogen, argon and helium.

[0116] The high-temperature medium provided by the energy storage module 29 includes but is not limited to at least one of steam, nitrogen and helium.

[0117] The energy storage module 29 heats the high-temperature medium by means of resistance heating and heat recovery.

[0118] The waste boiler module 217 is capable of generating steam at 350-450°C.

[0119] This embodiment also provides an operation mode of an electric cracking furnace system. Using the electric cracking furnace system provided by this embodiment, the method includes:

[0120] The electric cracking furnace system is purged: the third steam flow provided by the steam module 22 is used to sequentially purge the electric heating cracking gas chambers of the preheater 24, the mixer 25, the superheater 26, and the electric cracking furnace 27, and the purged flow is discharged into the sewage discharge module 12; wherein the third steam flow is obtained by mixing the steam of 1000 kg / h, 185°C, and 1.0 MPa provided by the dilution steam submodule 215 and the steam of 1000 kg / h, 350°C, and 1.35 MPa provided by the medium-pressure steam submodule;

[0121] Steam cracking is performed using an electric cracking furnace system: a 4000 kg / h cracking raw material flow is provided through a raw material distribution module 21, and naphtha is selected as the cracking raw material; the cracking raw material flow is preheated to 210° C. by a preheater 24 to obtain a preheated cracking raw material flow; a dilution steam submodule 215 provides 1000 kg / h, 185° C., 1.5 MPa of steam and a medium-pressure steam submodule provides 1000 kg / h, 350° C., 1.35 MPa of steam to obtain a first steam flow; the preheated cracking raw material flow and the first steam flow are mixed by a mixer 25 to obtain a cracking raw material and steam mixed flow; the cracking raw material and steam mixed flow The superheater 26 is used to preheat the temperature to 540°C to obtain a stream to be cracked; the stream to be cracked enters the electrically heated cracking gas chamber of the electric cracking furnace 27 and undergoes a steam cracking reaction at 850°C to obtain a cracking gas stream; the cracking gas stream is rapidly cooled to 250°C by the quenching module 213 to obtain a cooled cracking gas stream, wherein the boiler feed water of the waste boiler module 217 is used as the cooling medium of the quenching module 213 to rapidly cool the cracking gas stream entering the quenching module 213, and the boiler feed water after the quenching treatment of the cracking gas stream is transported back to the waste boiler module 217; the cooled cracking gas stream is separated and purified by the post-separation module 214;

[0122] The electric cracking furnace system is subjected to a decoking treatment: the decoking air flow of 800 kg / h provided by the decoking air module 23 is mixed with the second steam flow provided by the steam module 22, and then preheated to 300°C by the preheater 24, mixed by the mixer 25, and preheated to 550°C by the superheater 26 to obtain a decoking flow, wherein the second steam flow is obtained by mixing 2000 kg / h, 180°C, 1.0 MPa steam provided by the dilution steam submodule 215 and 800 kg / h, 350°C, 1.35 MPa steam provided by the medium-pressure steam submodule; the decoking flow enters the electrically heated cracking gas chamber of the electric cracking furnace 27 for a coking reaction, and the product after the coking reaction is discharged into the sewage discharge module 12;

[0123] During the process of using the electric cracking furnace system for steam cracking and decoking the electric cracking furnace system, the cooling module 211 is used to cool down the heating element of the electric heating cracking chamber of the electric cracking furnace 27 through a cooling medium; wherein the cooling medium is selected from boiler feed water;

[0124] During steam cracking using the electric cracking furnace system, the replacement gas module 28 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 27 in real time and to monitor the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 27 in real time; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 27 is the same as the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace 27, then the electric heating cracking chamber of the electric cracking furnace 27 has not leaked; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 27 is different from the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace 27, then the electric heating cracking chamber of the electric cracking furnace 27 has leaked, and the electric cracking furnace system is in an abnormal operating condition; wherein, nitrogen is selected as the replacement gas;

[0125] During the process of using the electric cracking furnace system for steam cracking, when the electric cracking furnace system is in an abnormal operating condition, the material supply to the electric cracking furnace 27 is stopped, and the heating function of the electric heating cracking chamber of the electric cracking furnace 27 is stopped, the material in the electric heating cracking chamber of the electric cracking furnace 27 is discharged into the flare module 210, and at the same time, the energy storage module 29 is used to inject high-temperature medium into the electric heating cracking chamber of the electric cracking furnace 27; wherein the high-temperature medium is medium-pressure steam with a temperature of 420°C.

[0126] In this embodiment, during the operation of the electric cracking furnace system, after the electric cracking furnace 7 reaches the final operating conditions (the tube wall temperature of the electric cracking furnace 7 is within 1100-1115°C, and the absolute pressure ratio of the venturi tube is 0.9), the electric cracking furnace system performs a decoking process to remove the coke layer in the tube of the electric cracking furnace 7. The operating cycle after decoking is 60-80 days. By switching between the two operating modes of normal operation and decoking, the long-term operation of the electric cracking furnace system is ensured.

[0127] When the electrolytic furnace system lacking the replacement gas module 28 and the energy storage module 29 encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 27 is urgently shut down, and the furnace tube of the electric cracking furnace 27 will be broken and need to be replaced. However, when the electric cracking furnace system in this embodiment encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 27 is urgently shut down, and the furnace tube of the electric cracking furnace 27 will not be damaged and can continue to be used. The electric cracking furnace system in this embodiment can effectively ensure that the furnace tube of the electric cracking furnace 27 is not damaged after the heating function is urgently shut down in an abnormal operating condition, thereby improving the service life of the furnace tube of the electric cracking furnace 27, and further improving the long-term stable operation performance of the electric cracking furnace system.

[0128] Example 3

[0129] This embodiment provides an electric cracking furnace system, such as Figure 4 As shown, the system includes a raw material distribution module 31, a steam module 32, a decoking air module 33, a preheater 34, a mixer 35, a superheater 36, an electric cracking furnace 37, a replacement gas module 38, an energy storage module 39, a flare module 310, a cooling module 311, a sewage discharge module 312, a quenching module 313, a post-separation module 314, a waste boiler module 317 and a steam cascade utilization module 318.

[0130] The electric cracking furnace 37 includes a replacement gas chamber and an electric heating cracking chamber. The electric heating cracking chamber is arranged inside the replacement gas chamber (that is, the replacement gas chamber is arranged outside the electric heating cracking chamber). The electric cracking furnace 37 is provided with an electric heating element cooling tube; the steam module 32 includes a dilution steam submodule 315 and a medium-pressure steam submodule 316. The steam outlet of the dilution steam submodule 315 is connected to the steam outlet of the medium-pressure steam submodule 316 and serves as the steam outlet of the steam module 32.

[0131] The discharge port of the raw material distribution module 31 is connected to the feed port of the preheater 34, the discharge port of the preheater 34 is connected to the feed port of the mixer 35, the steam outlet of the steam module 32 is connected to the feed port of the mixer 35, the discharge port of the mixer 35 is connected to the feed port of the superheater 36, the discharge port of the superheater 36 is connected to the feed port of the electric heating cracking chamber of the electric cracking furnace 37, the feed port of the quenching module 313 is connected to the discharge port of the electric heating cracking chamber of the electric cracking furnace 37, and the replacement The replacement gas outlet of the gas module 38 is connected to the replacement gas inlet of the replacement gas chamber of the electric cracking furnace 37, the replacement gas component detection inlet of the replacement gas module 38 is connected to the replacement gas outlet of the replacement gas chamber of the electric cracking furnace 37, the feed inlet of the flare module 310 is connected to the electric heating cracking chamber of the electric cracking furnace 37, the high temperature medium outlet of the energy storage module 39 is connected to the electric heating cracking chamber of the electric cracking furnace 37, and the cooling medium outlet of the cooling module 311 is connected to the electric heating element cooling pipe of the electric cracking furnace 37. The cooling medium inlet of the decoking air module 33 is connected, the discharge port of the decoking air module 33 is connected to the feed port of the preheater 34, the steam outlet of the steam module 32 is connected to the connecting pipeline between the discharge port of the decoking air module 33 and the feed port of the preheater 34, the sewage discharge module 312 is connected to the sewage discharge port of the electric heating cracking chamber of the electric cracking furnace 37, the feed port of the post-separation module 314 is connected to the discharge port of the quenching module 313, the cooling medium inlet and the cooling medium outlet of the quenching module 313 are both connected to the boiler feed water pipeline of the waste boiler module 317, so as to realize heat exchange between the boiler feed water and the cracking gas in the quenching module 313, the boiler feed water is used to cool the cracking gas, and the cracking gas is used to heat the boiler feed water, and the steam outlet of the steam gradient utilization module 318 is respectively connected to the steam supply inlet of the dilution steam submodule 315 of the steam module 32, the steam supply inlet of the medium-pressure steam submodule 316 of the steam module 32, and the steam inlet of the steam heating pipeline of the energy storage module 39.

[0132] The raw material distribution module 31 is used to provide cracking raw materials to the preheater according to demand; the preheater 34 is used to preheat the cracking raw materials; the mixer 35 is used to mix the cracking raw materials and steam; the superheater 36 is used to heat the mixture of the cracking raw materials and steam; the quenching module 313 is used to quickly reduce the temperature of the cracking gas, maximize the ethylene yield in the cracking gas and recover the waste heat in the cracking gas; the replacement gas module 38 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 37 and detect the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 37; the flare module 310 is used to receive the raw materials and product gas in the electric heating cracking chamber when the electric cracking furnace 37 has an abnormal operating condition (for example, the electric cracking furnace 37 is powered off, the electric heating cracking chamber leaks, etc.); the energy storage module 39 is used to provide high-temperature medium to the electric heating cracking chamber when the flare module 310 receives the raw materials and product gas in the electric heating cracking chamber; the post-separation module 314 is used to separate and purify the cracking gas.

[0133] The dilution steam submodule 315 is used to provide steam at 150-350°C and 0.5-2MPa. The steam provided by the dilution steam submodule 315 can be used to dilute cracking raw materials, purge the electric cracking furnace system, and cooperate with the decoking air to decoke the electric cracking furnace system.

[0134] The medium-pressure steam submodule 316 is used to provide steam at 200-450°C and 1.0-5.0MPa. The steam provided by the medium-pressure steam submodule can be used to purge the electric cracking furnace system and to clean the electric cracking furnace system in combination with the decoking air.

[0135] The quenching module 313 can reduce the temperature of the cracked gas to 150-550° C. according to the needs and the type of cracked gas.

[0136] The preheater 34 is an electric preheater, and the heating range of the electric preheater is 35-300°C.

[0137] The superheater 36 is an electric superheater, and the heating range of the electric superheater is 150-650°C.

[0138] The temperature of the high-temperature medium provided by the energy storage module 39 is 300-900°C.

[0139] The mixer 35 adopts a Venturi mixing type.

[0140] The cracking feedstock provided by the feedstock distribution module 31 includes, but is not limited to, crude oil, heavy oil, diesel, liquefied gas, butane and propane.

[0141] The electric heating cracking chamber of the electric cracking furnace 37 is heated by electromagnetic heating.

[0142] The cooling medium of the cooling module 311 includes, but is not limited to, one of air, water, alcohol, Freon, ammonia, carbon dioxide, liquid metal, liquid helium and liquid nitrogen.

[0143] The replacement gas provided by the replacement gas module 38 to the replacement gas chamber of the electric cracking furnace includes, but is not limited to, at least one of nitrogen, argon and helium.

[0144] The high-temperature medium provided by the energy storage module 39 includes but is not limited to at least one of steam, nitrogen and helium.

[0145] The energy storage module 39 heats the high-temperature medium by means of resistance heating.

[0146] The waste boiler module 317 is capable of generating steam at 350-450°C.

[0147] This embodiment also provides an operation mode of an electric cracking furnace system. Using the electric cracking furnace system provided by this embodiment, the method includes:

[0148] The electric cracking furnace system is purged: the third steam flow provided by the steam module 32 is used to sequentially purge the electric heating cracking gas chambers of the preheater 34, the mixer 35, the superheater 36, and the electric cracking furnace 37, and the purged flow is discharged into the sewage discharge module 12; wherein the third steam flow is obtained by mixing the steam of 1000 kg / h, 185°C, and 1.0 MPa provided by the dilution steam submodule 315 and the steam of 1000 kg / h, 350°C, and 1.35 MPa provided by the medium pressure steam submodule;

[0149] Steam cracking is performed using an electric cracking furnace system: a 4000 kg / h cracking raw material flow is provided through a raw material distribution module 31, and naphtha is selected as the cracking raw material; the cracking raw material flow is preheated to 210°C by a preheater 34 to obtain a preheated cracking raw material flow; a dilution steam submodule 315 provides 1000 kg / h, 185°C, 1.5 MPa of steam and a medium-pressure steam submodule provides 1000 kg / h, 350°C, 1.35 MPa of steam to obtain a first steam flow; the preheated cracking raw material flow and the first steam flow are mixed by a mixer 35 to obtain a cracking raw material and steam mixed flow; the cracking raw material and steam mixed flow are preheated to 540°C by a superheater 36 to obtain a flow to be cracked; the flow to be cracked enters the electrically heated cracking gas chamber of the electric cracking furnace 37 to undergo steam cracking reaction at 850°C to obtain a cracking gas flow; the cracking gas flow is quenched by a quenching module 313 The temperature is cooled to 250°C to obtain a cooled cracking gas flow, wherein the boiler feed water of the waste boiler module 317 is used as the cooling medium of the quenching module 313 to quench the temperature of the cracking gas flow entering the quenching module 313, and the boiler feed water after the quenching treatment of the cracking gas flow is transported back to the waste boiler module 317; the cooled cracking gas flow is separated and purified by the separation module 314; wherein the 400°C steam generated by the waste boiler module 317 is transported to the steam cascade utilization module 318, and the steam required by the dilution steam submodule 315 is prepared by the steam cascade utilization module 318 to supply the dilution steam submodule 315, the steam required by the medium-pressure steam submodule 316 is prepared by the steam cascade utilization module 318 to supply the medium-pressure steam submodule 316, and the steam used for heating the high-temperature medium in the energy storage module 39 is prepared by the steam cascade utilization module 318 and enters the energy storage module 39 to heat the high-temperature medium.

[0150] The electric cracking furnace system is subjected to a decoking treatment: the decoking air flow of 800 kg / h provided by the decoking air module 33 is mixed with the second steam flow provided by the steam module 32, and then preheated to 300°C by the preheater 34, mixed by the mixer 35, and preheated to 550°C by the superheater 36 to obtain a decoking flow, wherein the second steam flow is obtained by mixing 2000 kg / h, 180°C, 1.0 MPa steam provided by the dilution steam submodule 315 and 800 kg / h, 350°C, 1.35 MPa steam provided by the medium-pressure steam submodule; the decoking flow enters the electrically heated cracking gas chamber of the electric cracking furnace 37 for a coking reaction, and the product after the coking reaction is discharged into the sewage discharge module 12;

[0151] During the process of using the electric cracking furnace system for steam cracking and decoking the electric cracking furnace system, the cooling module 311 is used to cool the heating element of the electric heating cracking chamber of the electric cracking furnace 37 through the cooling medium; wherein the cooling medium is selected from boiler feed water;

[0152] During steam cracking using the electric cracking furnace system, the replacement gas module 38 is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace 37 in real time and monitor the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 37 in real time; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 37 is the same as the replacement gas composition provided to the replacement gas chamber of the electric cracking furnace 37, then the electric heating cracking chamber of the electric cracking furnace 37 has not leaked; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace 37 is different from the replacement gas composition provided to the replacement gas chamber of the electric cracking furnace 37, then the electric heating cracking chamber of the electric cracking furnace 37 has leaked, and the electric cracking furnace system is in an abnormal operating condition; wherein, nitrogen is selected as the replacement gas;

[0153] During the process of using the electric cracking furnace system for steam cracking, when the electric cracking furnace system is in an abnormal operating condition, stop feeding materials to the electric cracking furnace 37, and stop the heating function of the electric heating cracking chamber of the electric cracking furnace 37, discharge the materials in the electric heating cracking chamber of the electric cracking furnace 37 into the flare module 310, and use the energy storage module 39 to inject high-temperature medium into the electric heating cracking chamber of the electric cracking furnace 37; wherein the high-temperature medium is medium-pressure steam with a temperature of 420°C.

[0154] When the electrolytic furnace system lacking the replacement gas module 38 and the energy storage module 39 encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 37 is urgently shut down, and the furnace tube of the electric cracking furnace 37 will be broken and need to be replaced. However, when the electric cracking furnace system in this embodiment encounters an abnormal operating condition, the heating function of the electric heating cracking chamber of the electric cracking furnace 37 is urgently shut down, and the furnace tube of the electric cracking furnace 37 will not be damaged and can continue to be used. The electric cracking furnace system in this embodiment can effectively ensure that the furnace tube of the electric cracking furnace 37 is not damaged after the heating function is urgently shut down in an abnormal operating condition, thereby improving the service life of the furnace tube of the electric cracking furnace 37, and further improving the long-term stable operation performance of the electric cracking furnace system.

[0155] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An electric cracking furnace system, wherein: The system includes: Electric cracking furnace, displacement gas module, energy storage module and flare module; The electric cracking furnace comprises a replacement gas chamber and an electric heating cracking chamber, wherein the electric heating cracking chamber is arranged inside the replacement gas chamber; The replacement gas outlet of the replacement gas module is connected to the replacement gas inlet of the replacement gas cavity of the electric cracking furnace, and the replacement gas component detection inlet of the replacement gas module is connected to the replacement gas outlet of the replacement gas cavity of the electric cracking furnace; the replacement gas module is used to provide replacement gas to the replacement gas cavity of the electric cracking furnace and detect the components of the replacement gas discharged from the replacement gas cavity of the electric cracking furnace; The feed port of the flare module is connected to the electric heating cracking chamber of the electric cracking furnace. The flare module is used to receive the raw material and product gas in the electric heating cracking chamber when the electric cracking furnace has an abnormal working condition; The high temperature medium outlet of the energy storage module is connected to the electric heating cracking chamber of the electric cracking furnace. The energy storage module is used to provide high temperature medium to the electric heating cracking chamber when the flare module receives the raw materials and product gas in the electric heating cracking chamber.

2. The system according to claim 1, wherein: The electric cracking furnace system also includes a cooling module, and the electric cracking furnace is also provided with an electric heating element cooling pipe. The cooling medium outlet of the cooling module is connected to the cooling medium inlet of the electric heating element cooling pipe of the electric cracking furnace, and the cooling medium recovery port of the cooling module is connected to the cooling medium outlet of the electric heating element cooling pipe of the electric cracking furnace.

3. The system according to claim 1, wherein: The electric cracking furnace system also includes a preheater, a mixer, a superheater, a quench module and a steam module; The feed port of the preheater is used for feeding cracking raw materials, the discharge port of the preheater is connected to the feed port of the mixer, the steam outlet of the steam module is connected to the feed port of the mixer, the discharge port of the mixer is connected to the feed port of the superheater, the discharge port of the superheater is connected to the feed port of the electrically heated cracking chamber of the electric cracking furnace, and the feed port of the quenching module is connected to the discharge port of the electrically heated cracking chamber of the electric cracking furnace.

4. The system according to claim 3, wherein: The electric cracking furnace system also includes a decoking air module and a sewage discharge module; the discharge port of the decoking air module is connected to the feed port of the preheater, the steam outlet of the steam module is connected to the connecting pipeline between the discharge port of the decoking air module and the feed port of the preheater, and the sewage discharge module is connected to the sewage discharge port of the electrically heated cracking chamber of the electric cracking furnace.

5. The system according to claim 3, wherein: The steam module includes a dilution steam submodule and a medium-pressure steam submodule; the dilution steam submodule is used to provide steam at 120-300°C and 0.5-2MPa; the medium-pressure steam submodule is used to provide steam at 200-450°C and 1.0-5.0MPa.

6. The system according to claim 3, wherein: The steam outlet of the steam module is connected to the cooling medium inlet of the quench module, so that the steam of the steam module is used to cool the cracked gas in the quench module.

7. The system according to claim 3 or 6, wherein: The cooling medium inlet of the quenching module is connected to the water outlet of the process water system, so that the process water of the process water system is used to cool the cracked gas in the quenching module.

8. The system according to claim 3, wherein: The electric cracking furnace system also includes a waste boiler module. The cooling medium inlet and the cooling medium outlet of the quench module are connected to the boiler feed water pipeline of the waste boiler module, so as to realize heat exchange between the boiler feed water and the cracking gas in the quench module, and use the boiler feed water to cool the cracking gas and use the cracking gas to heat the boiler feed water.

9. The system according to claim 8, wherein: The electric cracking furnace system also includes a steam gradient utilization module, the steam inlet of the steam gradient utilization module is connected to the steam outlet of the waste boiler module, the steam outlet of the steam gradient utilization module is connected to the steam supply inlet of the steam module and / or is connected to the steam inlet of the steam heating pipeline of the energy storage module.

10. A method for operating an electric cracking furnace system, using the electric cracking furnace system according to any one of claims 1 to 9, the method comprising: In the process of using the electric cracking furnace system for steam cracking, the replacement gas module is used to provide replacement gas to the replacement gas chamber of the electric cracking furnace in real time and to monitor the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace in real time; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace is the same as the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace, then the electric heating cracking chamber of the electric cracking furnace has not leaked; if it is monitored that the composition of the replacement gas discharged from the replacement gas chamber of the electric cracking furnace is different from the composition of the replacement gas provided to the replacement gas chamber of the electric cracking furnace, then the electric heating cracking chamber of the electric cracking furnace has leaked, and the electric cracking furnace system is in an abnormal operating condition; During steam cracking using an electric cracking furnace system, when the electric cracking furnace system is in an abnormal operating condition, the material supply to the electric cracking furnace is stopped, and the heating function of the electric heating cracking chamber of the electric cracking furnace is stopped, the material in the electric heating cracking chamber of the electric cracking furnace is discharged into the flare module, and at the same time, a high-temperature medium is injected into the electric heating cracking chamber of the electric cracking furnace using an energy storage module; wherein the temperature of the high-temperature medium is 300-900°C.

11. The method according to claim 10, wherein: The high temperature medium includes at least one of steam, nitrogen and helium; The replacement gas includes at least one of nitrogen, argon and helium.

12. The method according to claim 10, wherein: The electric cracking furnace system operation method also includes: In the process of steam cracking using the electric cracking furnace system, the cracking feedstock flow is preheated by a preheater to obtain a preheated cracking feedstock flow, the preheated cracking feedstock flow and the first steam flow provided by the steam module are mixed by a mixer to obtain a cracking feedstock and steam mixed flow, the cracking feedstock and steam mixed flow are preheated by a superheater to obtain a stream to be cracked, the stream to be cracked enters the electrically heated cracking gas chamber of the electric cracking furnace to undergo a steam cracking reaction to obtain a cracking gas flow, and the cracking gas flow is rapidly cooled by a quenching module to obtain a cooled cracking gas flow; Preferably, in the steam cracking process using the electric cracking furnace system, the first steam flow includes 120-300°C, 0.5-2MPa steam provided by the dilution steam submodule in the steam module and / or 200-450°C, 1.0-5.0MPa steam provided by the medium-pressure steam submodule in the steam module.

13. The method according to claim 12, wherein: The operation method of the electric cracking furnace system also includes performing a coke cleaning process on the electric cracking furnace system: the coke cleaning air flow is mixed with the second steam flow provided by the steam module, and then preheated and heated in sequence by a preheater, mixed by a mixer, and preheated and heated again by a superheater to obtain a coke cleaning flow, the coke cleaning flow enters the electrically heated cracking gas chamber of the electric cracking furnace to perform a coke burning reaction, and the product after the coke burning reaction is discharged into the sewage discharge module; Preferably, in the decoking treatment of the electric cracking furnace system, the second steam flow includes 120-300°C, 0.5-2MPa steam provided by the dilution steam submodule in the steam module and / or 200-450°C, 1.0-5.0MPa steam provided by the medium-pressure steam submodule in the steam module.

14. The method according to claim 12, wherein: The operation method of the electric cracking furnace system also includes purging the electric cracking furnace system: the third steam flow provided by the steam module sequentially purges the preheater, mixer, superheater, and electrically heated cracking gas chamber of the electric cracking furnace, and the purged flow is discharged into the sewage discharge module.

15. The method according to claim 12, wherein: The electric cracking furnace system operation method also includes using a cooling module to cool down a heating element of an electrically heated cracking chamber of the electric cracking furnace through a cooling medium.

16. The method according to claim 12, wherein: The electric cracking furnace system operation method further includes: in the process of using the electric cracking furnace system to perform steam cracking, using the steam module to provide a fourth steam stream as a cooling medium of the quenching module to quench the cracked gas stream entering the quenching module; Preferably, the fourth steam stream comprises 120-300° C., 0.5-2 MPa steam provided by the dilution steam submodule in the steam module and / or 200-450° C., 1.0-5.0 MPa steam provided by the medium pressure steam submodule in the steam module.

17. The method according to claim 12 or 16, wherein: The electric cracking furnace system operation method also includes: during the steam cracking process using the electric cracking furnace system, using process water provided by the process water system as a cooling medium of the quenching module to quench the cracked gas flow entering the quenching module.

18. The method according to claim 12, wherein: The operation method of the electric cracking furnace system also includes: during the process of using the electric cracking furnace system to perform steam cracking, using the boiler feed water of the waste boiler module as the cooling medium of the quenching module to quench the cracked gas flow entering the quenching module, and re-transporting the boiler feed water after the quenching treatment of the cracked gas flow back to the waste boiler module.

19. The method according to claim 12, wherein: The operation method of the electric cracking furnace system also includes: during the steam cracking process using the electric cracking furnace system, the steam generated by the waste boiler module is transported to the steam cascade utilization module, the steam required by the steam module is prepared by the steam cascade utilization module to supply the steam module, or the steam used to heat the high-temperature medium of the energy storage module is prepared by the steam cascade utilization module, and the steam enters the energy storage module to heat the high-temperature medium.

20. The method according to claim 12, wherein: The heating temperature of the preheater is 25-300℃; The heating temperature of the superheater is 150-650℃; The quenching module reduces the cracking gas to 150-550℃; The cracking feedstock includes at least one of crude oil, heavy oil, diesel, liquefied gas, butane and propane.

Images