Quench cooler electric de-coking device and electric de-coking process

Abstract

The application relates to an electric de-coking device and process of a quencher, belonging to the field of petrochemical industry. The device comprises a current transformation controller, an input electrode, an output electrode, an input detection electrode, an output detection electrode, a detector and a pulse power supply. The input electrode and the input detection electrode are connected to the inlet end of the quencher furnace tube, the output electrode and the output detection electrode are connected to the outlet end of the quencher furnace tube, and the detector is connected to the input detection electrode and the output detection electrode. The current transformation controller loads the set voltage and current to the two ends of the quencher furnace tube through the input electrode and the output electrode to form an electromagnetic field in the quencher furnace tube; the flowing direction of the reaction material in the quencher furnace tube should be the same as the flowing direction of the current; and the input detection electrode and the output detection electrode are used for real-time detection of the voltage at the two ends of the quencher furnace tube. The application improves the de-coking effect, can be applied to de-coking at high temperature and purification of oxygen-containing flue gas, and prolongs the operation cycle of the quencher.

Description

Technical Field

[0001] This invention belongs to the field of petrochemical technology, specifically relating to a quench cooler electrostatic precipitator and electrostatic precipitator process. Background Technology

[0002] During ethylene production, the high-temperature material in the quench cooler tubes of an ethylene plant drops from approximately 800°C to 500°C. Some of this material condenses due to the sudden temperature drop and adheres to the inner wall of the tubes. Over time, this adhered material accumulates, containing a large amount of unsaturated olefins and other substances. These substances undergo polymerization reactions at high temperatures, leading to impaired material flow and increased pressure drop. If regeneration measures are not taken to clean this blockage, the quench cooler will eventually become completely clogged, causing unplanned shutdowns and even safety accidents. Quench cooler failure severely impacts the normal operation of the ethylene plant, potentially leading to shutdown. Therefore, implementing appropriate regeneration and decoking processes for the quench cooler is crucial for the stable operation of the ethylene plant.

[0003] Currently, the traditional regeneration decoking processes used in ethylene plants for quench coolers are air burning and manual hydraulic decoking. Generally, air burning and manual hydraulic decoking are performed after two cycles of quench cooler operation. Therefore, a complete regeneration decoking cycle includes: two cycles of air burning + one manual hydraulic decoking (for liquid feedstock, two cycles take approximately 90 days). Air burning involves heating air and steam to approximately 800°C and introducing them into the quench cooler tubes. The hot air and steam react with the coke layer within the tubes, gradually reducing its density. However, because the quench cooler at the rear end has a different structure than the furnace tubes at the front end, the burning temperature of the hot air and steam upon arrival is lower, only around 500°C, which is insufficient to reach the approximately 800°C required for air burning. This results in ineffective removal of the coke layer, with some unreacted or unreacted material remaining adhered to the tube walls. Therefore, manual hydraulic decoking must be performed after two cycles of air burning. Manual hydraulic descaling is a physical removal method that requires completely stopping the operation of the quench cooler, lowering it to room temperature, and disassembling the quench cooler head. The quench cooler is then cleaned using physical methods such as mechanical rotating heads and high-pressure water. Since the quench cooler contains dozens or even hundreds of tubes, each tube needs to be cleaned individually. This is not only time-consuming and labor-intensive but also prone to omissions. Furthermore, during the cleaning process, the mechanical rotating heads and high-pressure water can damage the tube structure, causing the quench cooler to fail. This not only affects the normal production of the ethylene plant but also increases its energy and material consumption, severely impacting the economic benefits of ethylene production.

[0004] Chinese patent CN102925196A discloses a coking prevention device for the high-temperature pyrolysis gas inlet of an oil-gas quencher. In this device, a coking removal steam ring is concentrically arranged at the oil-gas outlet of the inlet pipe, and steam holes are provided on the coking removal steam to achieve coking removal. This patent only solves the coking problem at the quencher inlet; coking still easily occurs inside the quencher, and it cannot remove the generated coke layer online. Chinese patent CN107541238A discloses a thermal pyrolysis simulation experimental device and coking removal method. The circulating quenching recovery system involved in this patent mainly includes a pyrolysis gas circulating quenching loop composed of a mixing quencher, an indirect quencher, a cyclone separator, a gas circulation pump, and a cooler. The quenching system injects quenching water into the coke layer inside the quencher to remove coke near the water injection pipe. The patented circulating quench recovery system has a complex structure and an additional circulation system, which greatly increases the equipment investment cost and process complexity, making it uneconomical. Moreover, it can only remove coking near the water injection pipe and cannot solve the coking problem inside the quencher.

[0005] Improving the technological performance of the quench cooler without altering its main structure and requiring only a small increase in equipment investment is a challenge faced by most ethylene production plants. The quench cooler's operating cycle directly impacts the cracking cycle; a longer operating cycle means fewer shutdowns for coking, longer effective production time for the cracking unit, lower energy consumption per ton of ethylene, and better economic and technical efficiency. In today's world, with dwindling traditional energy sources and increasing emphasis on carbon emissions, energy-efficient quench coolers that reduce coking are of significant practical importance in saving energy, reducing environmental pollution, and lowering production costs.

[0006] Electrostatic precipitator (ESP) is a rapidly developing new technology in recent years, applicable to chemical reactions and separation. Currently, ESP is mainly used in exhaust gas and air purification processes. Its working principle involves a metal tube with a metal wire at its center. The metal tube is grounded as the collecting electrode, and the metal wire is connected to a high-voltage power supply (above 30kV) as the discharging electrode. When coal gas carrying tar dust enters the electric field created by these two electrodes, the tar dust absorbs the charge released by the discharging electrode, thus acquiring the same charge. This charged tar dust attracts other uncharged particles, combining with them to form larger particles, which eventually fall from the gas flow due to gravity. Simultaneously, under the influence of the electric field, the charged tar dust moves towards the collecting electrode, loses its charge upon contact, and adheres to the inner wall of the metal tube. Finally, it falls due to gravity or mechanical vibration, and the collected tar dust is discharged through the tar dust outlet. This electrostatic precipitator requires the construction of a complex high-voltage electrostatic precipitator tower, making it unsuitable for ethylene cracking and coking operations involving oxygen and high temperatures. Since electrostatic precipitator uses high voltages exceeding 30kV, with a centrally mounted metal wire as the discharge electrode, the wire becomes unstable under the 500℃ high-temperature cracking and coking conditions. High-voltage discharge could cause an explosion of coke and air within the quench cooler, severely threatening the safe operation of the unit. Furthermore, the centrally mounted metal wire discharge electrode cannot withstand the 500℃ temperature and the high-speed airflow of 160m / s, quickly failing. Additionally, the cracking quench cooler is a closed system, making it impossible to increase the number of tar and dust discharge outlets; therefore, there are no reports of its use for quench cooler decoking.

[0007] For example, Chinese patent CN209093613U discloses an electrostatic precipitator that requires the construction of a complex high-voltage electrostatic precipitator tower, including the precipitator body and a DC power supply. The precipitator body has a baffle plate inside, with gas pipes evenly arranged within the baffle plate's interior, penetrating both the top and bottom of the baffle plate. Each set of gas pipes has a high-voltage electric field negative electrode wire connected to the negative terminal of the DC power supply, achieving the effect of removing impurities from the gas. This patent merely adds a baffle plate and is essentially no different from ordinary electrostatic precipitators. High-voltage discharge cannot be used for precipitator removal in quenchers, as it could cause the coke and air inside the quencher to explode, seriously threatening the safe operation of the device. Furthermore, the quencher is a closed system, making it impossible to increase the number of tar and dust outlets. The gas flows at high speed within the tubes, reaching 80 m / s, and falling tar and dust cannot be collected; they are immediately carried away by the high-speed airflow, failing to achieve the desired removal. No reports have been found regarding its use for precipitator removal in quenchers.

[0008] For example, Chinese patent CN2882795Y discloses a honeycomb-type high-voltage electrostatic tar remover and dust collector. This requires the construction of a complex high-voltage electrostatic tar removal tower, including a shell with a gas inlet, gas outlet, and sewage outlet. At the upper end of the shell are a high-voltage inlet box, intermittent flushing pipes, and an upper frame. The upper frame is connected to a high-voltage DC generator via high-voltage insulators inside the high-voltage inlet box. Corona wires connected to the upper and lower frames are located inside a hexagonal cylinder, forming a high-voltage DC strong electric field together with the hexagonal cylinder. This patent simply divides a large cavity into smaller honeycomb-shaped cavities, essentially no different from ordinary electrostatic tar removal. High-voltage discharge cannot be used for tar removal in quench coolers, as it could cause an explosion of coke and air inside the quench cooler, seriously threatening the safe operation of the device, and the structure is complex. Since the quench cooler is a closed system, it is impossible to increase the number of outlets for tar and dust. Furthermore, the gas flows at a high speed of 80 m / s inside the tubes, and the falling tar and dust cannot be collected. They will be immediately carried away by the high-speed airflow, making it impossible to achieve the purpose of removal. There are no reports of it being used for tar removal in quench coolers.

[0009] In summary, there is an urgent need to develop a decoking device and process suitable for quench coolers. Summary of the Invention

[0010] To address the problems of rapid coking, short operating cycle, short tube life, high energy consumption, and low production efficiency in quench coolers during ethylene production, as well as the issues of traditional electrostatic precipitator processes such as the need to construct complex and expensive high-voltage electrostatic precipitator towers or cylinders, high-voltage discharge safety issues, inability to be used at high temperatures, unsuitability for oxygen-containing flue gas purification, and poor coking removal effect, this invention provides a quench cooler electrostatic precipitator device and electrostatic precipitator process.

[0011] The technical solution adopted by this invention to solve the technical problem is as follows:

[0012] The present invention provides an electrostatic precipitator for a quench cooler, which mainly includes:

[0013] Pulse power supply;

[0014] A current conversion controller connected to a pulse power supply;

[0015] The input electrode and output electrode are respectively connected to the current conversion controller; the input electrode is connected to the inlet end of the quench cooler furnace tube, and the output electrode is connected to the outlet end of the quench cooler furnace tube; the current conversion controller applies the set voltage and current to both ends of the quench cooler furnace tube through the input electrode and the output electrode, thereby forming an electromagnetic field in the quench cooler furnace tube; the flow direction of the reactant material in the quench cooler furnace tube is the same as the flow direction of the current.

[0016] An input detection electrode and an output detection electrode are respectively connected to the furnace tube of the quench cooler; the input detection electrode is connected to the inlet end of the furnace tube of the quench cooler, and the output detection electrode is connected to the outlet end of the furnace tube of the quench cooler; the input detection electrode and the output detection electrode detect the voltage across the furnace tube of the quench cooler in real time.

[0017] A detector that is connected to the input detection electrode and the output detection electrode respectively.

[0018] Furthermore, the voltage range of the pulse power supply is 37V to 380V; the current range of the pulse power supply is 1mA to 10mA; and the frequency range of the DC pulse current is 5Hz to 60Hz.

[0019] Furthermore, the input electrode, output electrode, input detection electrode, and output detection electrode are all made of nickel-based high-temperature alloys, titanium-based high-temperature alloys, or molybdenum-based high-temperature alloys.

[0020] Furthermore, the input electrode, output electrode, input detection electrode, and output detection electrode are all equipped with cooling radiators.

[0021] Furthermore, the cooling radiator is an active cooling structure or a passive cooling structure; the active cooling structure is an air-cooled cooling structure or a water-cooled cooling structure; the passive cooling structure is a finned cooling structure or a microchannel cooling structure.

[0022] Furthermore, the cross-sections of the input electrode, output electrode, input detection electrode, and output detection electrode are all circular, square, triangular, or polygonal; and the end faces of the input electrode, output electrode, input detection electrode, and output detection electrode are all planar or curved surfaces.

[0023] Furthermore, the current output by the current conversion controller enters the quench furnace tube through the input electrode and flows out of the quench furnace tube through the output electrode, forming a closed loop.

[0024] The present invention provides a quench cooler electrostatic precipitator process, which is implemented using the aforementioned quench cooler electrostatic precipitator device, and specifically includes the following steps:

[0025] The reactants containing tar and coke particles from the radiant furnace tubes enter the quench cooler. Within the quench cooler tubes, the reactants move at high speed along with other gaseous hydrocarbons, causing the tar and coke particles to acquire a positive charge, while the other gaseous hydrocarbons acquire a negative charge. According to Coulomb's law of electromagnetism, there is an interaction force between different charges. The positively charged tar and coke particles, attracted by electrostatic forces, detach from the reactants and adsorb onto the inner surface of the quench cooler tubes, continuously accumulating. When the electrostatic decoking device is activated, current flows through the quench cooler tubes, creating an electromagnetic field on their surface. When the flow direction of the tar and coke particles within the quench cooler tubes aligns with the direction of the electromagnetic field, the field hinders the positively charged particles from approaching the tube wall, slowing their accumulation on the tube wall and allowing them to pass through the quench cooler tubes as much as possible, reducing their accumulation time on the tube wall and extending the quench cooler's operating cycle.

[0026] The beneficial effects of this invention are:

[0027] 1. Addressing the issue of traditional electrostatic precipitator processes requiring the construction of complex and expensive high-voltage electrostatic precipitator towers or cylinders, this invention eliminates the need for such towers. Instead, a pulsed low-voltage electromagnetic field is applied only to the inlet and outlet of the quench cooler tubes. The low-voltage standard conforms to GB / T 12325-2008, with a voltage below 1000 volts. An effective current is set, and the voltage and current of the electromagnetic field are effectively controlled by a current conversion controller. This creates a pulsed electromagnetic field within the quench cooler tubes. When the flow direction of tar and coke particles within the quench cooler tubes aligns with the direction of the electromagnetic field, these particles are more easily drawn through the tubes rather than adsorbed onto their inner surface, thus reducing carbon buildup. This invention eliminates the need for the high-voltage electrostatic precipitator towers or cylinders required in traditional electrostatic precipitator processes, thereby reducing the cost of electrostatic precipitator processes. In addition, without altering the existing pyrolysis device, the present invention can reduce coking in the quench cooler tubes by adding a small amount of equipment, thereby improving the quench cooler's operating cycle and economic efficiency, which is in line with low-carbon green chemical technology specifications.

[0028] 2. To address the high-voltage discharge safety issues inherent in traditional electrostatic decoking processes, this invention utilizes a current conversion controller to adjust the operating voltage and current, adapting to different stages of quencher operation. Specifically, to balance electrostatic decoking effectiveness and operational safety, the pulse power supply voltage range is preferably 37V–380V, the current range is preferably 1mA–10mA, and the DC pulse current frequency range is preferably 5Hz–60Hz. Simultaneously, input and output detection electrodes are connected to both ends of the quencher furnace tube. These electrodes allow for real-time monitoring of the voltage across the furnace tube; both excessively low and high voltage trigger audible and visual alarms. Therefore, the safety of the device operation is improved, preventing high-voltage discharge safety issues.

[0029] 3. Addressing the issue that traditional electrostatic precipitator processes cannot operate at high temperatures, conventional electrostatic precipitator devices are only suitable for low-temperature exhaust gas purification below 250℃, and their electrodes cannot operate under the high-temperature conditions of 500℃ in the quench cooler. The electrostatic precipitator device for the quench cooler of this invention has a wider applicable temperature range, suitable for most high and low temperature environments, specifically applicable to a temperature range of -100℃ to 1300℃.

[0030] 4. Addressing the issue that traditional electrostatic precipitator processes are unsuitable for purifying oxygen-containing flue gas, traditional electrostatic precipitators utilize the Coulomb effect of an electric field to remove dust. They primarily consist of electrodes, a collection plate, a high-voltage power supply, and a control system. When flue gas passes through the electric field between the electrodes and the collection plate, dust particles are charged by the electric field and deposited on the collection plate, thus removing the dust. However, traditional electrostatic precipitators use high-voltage electricity exceeding 30kV. Since the quench cooler contains conductive media such as water vapor, self-discharge can easily occur inside the quench cooler tubes, potentially leading to combustion and explosion of combustibles, especially when a large amount of air is present during coking, causing serious safety issues. Even in oxygen-free flue gas purification processes, strict oxygen content monitoring is necessary to prevent accidents. Furthermore, electrodes are prone to high-voltage discharge and damage under high voltage conditions. The operating principle and operating conditions of this invention differ from those of electrostatic precipitators based on thermal radiation in pyrolysis furnaces. In this invention, the electrostatic decoking of the quench cooler tubes operates in a non-thermal reaction environment below 600°C, where no chemical reaction occurs; only the high-temperature material is cooled, and heat energy is recovered to generate steam. The coking mechanism in the quench cooler is condensation coking, and the coked material is a liquid-solid mixed coke particle. Furthermore, this invention uses a DC pulse current of 36V or higher for electrostatic decoking. This DC pulse current produces an effect similar to an impact rotor, resulting in stronger decoking force. Additionally, the DC pulse current generates stronger electromagnetic disturbances, hindering the liquid-solid mixed coke particles from approaching the quench cooler tube wall. Therefore, this invention is suitable for the purification of oxygen-containing flue gas.

[0031] 5. In view of the problem of poor decoking effect in traditional electrostatic decoking processes, the present invention has confirmed through relevant comparative tests that the electrostatic decoking device and electrostatic decoking process of the quench cooler provided by the present invention improve the decoking effect, and the decoking effect is superior to that of the prior art.

[0032] 6. The electrostatic decoking device and electrostatic decoking process for a quench cooler provided by the present invention will not affect the yield and selectivity of the target product of the pyrolysis product, while inhibiting the accumulation of coke particles in the quench cooler furnace tube and improving the decoking effect. Attached Figure Description

[0033] Figure 1 This invention provides a structural block diagram of a quencher electrostatic decoking device.

[0034] In the diagram, 1 is the current conversion controller, 2 is the input electrode, 3 is the output electrode, 4 is the input detection electrode, 5 is the output detection electrode, 6 is the detector, 7 is the pulse power supply, 8 is the quencher furnace tube, 9 is the tar and coke particle mixture, and 10 is the reactant. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to the accompanying drawings.

[0036] In a first aspect, the present invention provides a quench cooler electrostatic decoking device.

[0037] like Figure 1 As shown, the electrostatic precipitator for a quench cooler of the present invention has a unique structure and is a key device for realizing the electrostatic precipitator process of pyrolysis. It mainly includes: a current conversion controller 1, an input electrode 2, an output electrode 3, an input detection electrode 4, an output detection electrode 5, a detector 6, and a pulse power supply 7.

[0038] The electrostatic decoking device for a quencher of this invention shall be powered by low-voltage electricity less than 1000V, and its standard is GB / T12325-2008. Pulsed direct current refers to electricity whose direction (positive and negative terminals) remains constant, but whose magnitude changes over time. For example, a typical pulsed direct current is obtained by rectifying 50Hz alternating current through a diode; a 50Hz pulsed direct current is obtained by rectifying 50Hz alternating current through a half-wave rectifier; and a 100Hz pulsed direct current is obtained by rectifying 50Hz alternating current through a full-wave or bridge rectifier.

[0039] The present invention discloses a quench cooler electrostatic decoking device, wherein the voltage range of the pulse power supply 7 is DC voltage from 37V to 1000V. The quench cooler electrostatic decoking device of the present invention exhibits electrostatic decoking effect at different voltages within the 37V to 1000V range, but the electrostatic decoking effect varies with different voltages, with higher voltages showing relatively better electrostatic decoking effect. Therefore, for operational safety, the pulse power supply 7 is designed as a DC pulse current with a voltage less than 380V, and to balance the electrostatic decoking effect and operational safety, the voltage range of the pulse power supply 7 is preferably 37V to 380V.

[0040] The present invention discloses an electrostatic decoking device for a quench cooler, wherein the pulse power supply 7 has a current range of 0.01mA to 10000mA pulsed DC current. The electrostatic decoking device of the present invention exhibits electrostatic decoking effect at different currents within the range of 0.01mA to 10000mA, but the effect varies with different currents, with higher currents generally providing better decoking effect. Therefore, to comply with the national standard "Safe Current" and ensure operational safety, the pulse power supply 7 is designed as a DC pulse current of less than 15mA, and to balance the electrostatic decoking effect and operational safety, the current range of the pulse power supply 7 is preferably 1mA to 10mA.

[0041] The present invention discloses a quencher electrostatic decoking device, wherein the pulse power supply 7 adopts a DC pulse current, and the frequency range of the DC pulse current can be 0.1Hz to 1000Hz. From the perspective of electrostatic decoking effect, the frequency range of the DC pulse current is preferably 5Hz to 60Hz.

[0042] In this invention, the pulse power supply 7 is connected to the current conversion controller 1, which is connected to the input electrode 2 and the output electrode 3. The input electrode 2 and the output electrode 3 are connected to the quench cooler tube 8, respectively, and are located at the inlet and outlet ends of the quench cooler tube 8. The current conversion controller 1 applies the set voltage and current to both ends of the quench cooler tube 8 through the input electrode 2 and the output electrode 3. After the electrostatic precipitator is started, the current conversion controller 1 converts ordinary alternating current into pulsed direct current. The current output by the current conversion controller 1 enters the quench cooler tube 8 through the input electrode 2. Current flows through the quench cooler tube 8, forming an electromagnetic field. After passing through the quench cooler tube 8, the current flows out through the output electrode 3 or the grounding wire, forming a closed loop.

[0043] In this invention, the input electrode 2 and the output electrode 3 are both connected to the quench furnace tube 8 via metallic materials. The connection method can be bolting, welding, etc., but welding is preferred to achieve a seamless connection to prevent energy loss.

[0044] In this invention, both the input electrode 2 and the output electrode 3 are made of high-temperature resistant materials, capable of withstanding temperatures up to 800°C. The high-temperature resistant material can be a nickel-based high-temperature alloy, a titanium-based high-temperature alloy, or a molybdenum-based high-temperature alloy, etc. To balance high-temperature resistance with electrode design, a titanium-based high-temperature alloy is preferred, as it possesses excellent corrosion resistance, oxidation resistance, heat resistance, and acid and alkali resistance.

[0045] In this invention, both the input electrode 2 and the output electrode 3 are equipped with cooling radiators. Using cooling radiators increases the heat dissipation area and optimizes the heat conduction path, improving the heat dissipation effect and reducing the high temperature of approximately 500°C of the quencher furnace tube 8 to the withstand temperature of the electrode cables.

[0046] In this invention, the cooling radiator can be an active cooling structure or a passive cooling structure, preferably a passive cooling structure. The active cooling structure can be an air-cooled cooling structure or a water-cooled cooling structure, preferably an air-cooled cooling structure; the passive cooling structure can be a finned cooling structure or a microchannel cooling structure, preferably a finned cooling structure.

[0047] In this invention, the cross-sections of the input electrode 2 and the output electrode 3 can be circular, square, triangular, or any polygon; the end faces of the input electrode 2 and the output electrode 3 can be planar or curved.

[0048] In this invention, the input electrode 2 and the output electrode 3 are preferably cylindrical structures.

[0049] In this invention, the input detection electrode 4 and the output detection electrode 5 are respectively connected to the quench cooler tube 8, and are located at the inlet and outlet ends of the quench cooler tube 8, respectively. Both the input detection electrode 4 and the output detection electrode 5 are connected to the detector 6. After the electrostatic precipitator is started, the current output by the current conversion controller 1 enters the quench cooler tube 8 through the input electrode 2. Current flows through the quench cooler tube 8, forming an electromagnetic field. After passing through the quench cooler tube 8, the current flows out through the output electrode 3 or the grounding wire, forming a closed loop. Simultaneously, the input detection electrode 4 and the output detection electrode 5 are connected to both ends of the quench cooler tube 8. The detector 6 can detect the voltage of the input detection electrode 4 and the output detection electrode 5 in real time, i.e., the voltage across the quench cooler tube 8 in real time. If the voltage is too low or too high, the detector 6 will trigger an audible and visual alarm.

[0050] In this invention, the input detection electrode 4 and the output detection electrode 5 are both connected to the quench furnace tube 8 via metallic materials. The connection method can be bolted, welded, etc., but welding is preferred to achieve a seamless connection to prevent signal attenuation.

[0051] In this invention, both the input detection electrode 4 and the output detection electrode 5 are made of high-temperature resistant materials, capable of withstanding temperatures up to 800°C. The high-temperature resistant material can be a nickel-based high-temperature alloy, a titanium-based high-temperature alloy, or a molybdenum-based high-temperature alloy, etc. To balance high-temperature resistance with electrode design, a titanium-based high-temperature alloy is preferred, as it possesses excellent corrosion resistance, oxidation resistance, heat resistance, and acid and alkali resistance.

[0052] In this invention, both the input detection electrode 4 and the output detection electrode 5 are equipped with cooling radiators. Using cooling radiators increases the heat dissipation area and optimizes the heat conduction path, improving the heat dissipation effect and reducing the high temperature of approximately 800°C in the quencher furnace tube 8 to the withstand temperature of the detection cable.

[0053] In this invention, the cooling radiator can be an active cooling structure or a passive cooling structure, preferably a passive cooling structure. The active cooling structure can be an air-cooled cooling structure or a water-cooled cooling structure, preferably an air-cooled cooling structure; the passive cooling structure can be a finned cooling structure or a microchannel cooling structure, preferably a finned cooling structure.

[0054] In this invention, the cross-sections of the input detection electrode 4 and the output detection electrode 5 can be circular, square, triangular, or any polygon; the end faces of the input detection electrode 4 and the output detection electrode 5 can be planar or curved.

[0055] In this invention, the input detection electrode 4 and the output detection electrode 5 are preferably cylindrical structures.

[0056] The present invention provides an electrostatic precipitator for a quencher, which can be installed inside an explosion-proof control cabinet to improve operational safety.

[0057] The present invention provides a quencher electrostatic precipitator with a working power of 0.1W to 1000kW. Preferably, the working power is 100W to 10kW.

[0058] The present invention provides a quencher electrostatic decoking device with an operating voltage of 37V to 1000V. Preferably, the operating voltage is 37V to 380V.

[0059] The present invention provides an electrostatic decoking device for a quench cooler, wherein the operating current is 0.01mA to 10000mA. Preferably, the operating current is 1mA to 10mA.

[0060] The electrostatic precipitator for a quench cooler according to the present invention can adjust the operating voltage through a current conversion controller 1 to adapt to different stages of quench cooler operation. For example, in the initial stage of quench cooler operation, the surface of the quench cooler furnace tube 8 is relatively clean, and the operating voltage can be lower, preferably in the range of 37V to 220V; while in the final stage of quench cooler operation, the surface of the quench cooler furnace tube 8 is covered with a coke layer, and the operating voltage should be increased, preferably in the range of 220V to 380V.

[0061] The electrostatic precipitator for a quench cooler of the present invention can adjust the operating current through a current conversion controller 1 to adapt to different stages of quench cooler operation. For example, in the initial stage of quench cooler operation, the surface of the quench cooler furnace tube 8 is relatively clean, and the operating current can be lower, preferably in the range of 1mA to 5mA; while in the final stage of quench cooler operation, the surface of the quench cooler furnace tube 8 is covered with a coke layer, and the operating current should be increased, preferably in the range of 5mA to 10mA.

[0062] For reliable and stable decoking devices suitable for industrial applications, the maximum output power can only reach about 20 kilowatts. However, in practical applications, the rated power that can operate stably for a long period is only about 10 kilowatts. In situations where the decoking effect needs to be enhanced, multiple sets of the electrostatic decoking devices of this invention can be connected in parallel to achieve a better decoking effect.

[0063] The present invention provides a quencher electrostatic precipitator that solves many problems existing in traditional electrostatic precipitators, such as the need to build a complex and expensive high-voltage electrostatic precipitator tower or cylinder, high-voltage discharge safety issues, inability to be used at high temperatures, and unsuitability for oxygen-containing flue gas purification.

[0064] Furthermore, the electrostatic precipitator for a quench cooler of the present invention also solves the problem of high-temperature precipitator removal in traditional electrostatic precipitators. Traditional electrostatic precipitators are only suitable for low-temperature exhaust gas purification below 250°C, and their electrodes cannot operate under the high-temperature conditions of 500°C in quench coolers. The electrostatic precipitator for a quench cooler of the present invention has a wider applicable temperature range, suitable for most high- and low-temperature environments, specifically applicable to a temperature range of -100°C to 1300°C.

[0065] Secondly, the present invention provides a quench cooler electrostatic decoking process, which is mainly implemented by the quench cooler electrostatic decoking device provided in the first aspect above.

[0066] The specific implementation process of the electrostatic decoking process for a quench cooler according to the present invention is as follows:

[0067] Cracking gas containing tar and coke particles from the thermal radiant furnace tube at around 800°C enters the quench cooler. The reactant material 10 containing tar and coke particles moves at high speed along with other gaseous hydrocarbons in the quench cooler tube 8, with a speed of 80-120 m / s. Since the mass of tar and coke particles is greater than that of other gaseous hydrocarbons, their moving speed is also lower. This speed difference causes the other gaseous hydrocarbons to continuously scour and rub against the coke particles. During this process, static electricity is generated by friction, causing the tar and coke particles to become positively charged and the other gaseous hydrocarbons to become negatively charged. Since the quench cooler tube 8 is made of metal, it is generally grounded. According to Coulomb's law of electromagnetism, there is an interaction force between different charges. Under the attraction of the electrostatic force, the positively charged tar and coke particles are easily detached from the reactant material 10 and adsorbed onto the inner surface of the quench cooler tube 8, continuously accumulating to form a tar and coke particle mixture 9, which in turn blocks the quench cooler tube 8. When the electrostatic precipitator of the quench cooler of the present invention is started, current flows through the quench cooler tube 8, and an electromagnetic field is formed on the surface of the quench cooler tube 8. When the magnetic field lines reach a suitable direction and intensity, the electromagnetic field will hinder the positively charged tar and coke particles from approaching the tube wall of the quench cooler tube 8, thereby slowing down their accumulation on the tube wall of the quench cooler tube 8, allowing them to pass through the quench cooler tube 8 as much as possible, reducing their accumulation time on the tube wall of the quench cooler tube 8, and extending the operating cycle of the quench cooler.

[0068] According to Ampere's law of electromagnetism, the magnitude and direction of the current in any conductor determine the magnitude and direction of the magnetic field generated. This law states that the essence of electric current is a moving charge, which produces a magnetic field. When the electrostatic precipitator of the quench cooler of this invention is started, the current output by the current conversion controller 1 enters the quench cooler furnace tube 8 through the input electrode 2. After passing through the quench cooler furnace tube 8, the current flows out through the output electrode 3 or the grounding wire, forming a closed loop.

[0069] When the flow direction of the reactant material 10 in the quencher tube 8 is consistent with the flow direction of the current in the electrostatic decoking process, that is, the current output by the current conversion controller 1 enters through the input electrode 2 and flows out from the output electrode 3 or from the grounding wire, the reactant material 10 enters the quencher tube 8 through the input electrode 2 and flows out from the output electrode 3. At this time, due to the electromagnetic field effect of the tube wall of the quencher tube 8, the coke particles generate a repulsive force and are not easily adsorbed on the tube wall of the quencher tube 8. Through the quencher tube 8, the amount of coke is greatly reduced, thereby extending the operating cycle of the quencher.

[0070] When the flow direction of the reactant material 10 in the quencher tube 8 is inconsistent with the current flow direction of the electrostatic decoking, that is, the current output by the current conversion controller 1 enters through the input electrode 2 and flows out from the output electrode 3 or from the grounding wire, while the reactant material 10 enters the quencher tube 8 through the output electrode 3 and flows out from the input electrode 2, the coke particles are deflected due to the electromagnetic field effect of the tube wall of the quencher tube 8. During the forward movement, the coke particles are prone to radial movement and deflection towards the tube wall of the quencher tube 8, and are easily adsorbed on the tube wall of the quencher tube 8, which greatly increases the amount of coke and causes the operating cycle of the quencher to be shorter than the operating cycle under normal conditions.

[0071] The electrostatic decoking process of the quench cooler of this invention differs in its operating principle and operating conditions from that of electrostatic decoking in the thermal radiation of a pyrolysis furnace. First, the electrostatic decoking of the thermal radiation furnace tubes of a pyrolysis furnace operates in a thermal reaction environment above 1000°C. The pyrolysis coking mechanism of thermal radiation is free radical coking, where polycyclic aromatic hydrocarbons and other coking precursors in the high-temperature gas continue to dehydrogenate into coke particles, and the coke particles are solid coke particles. The pyrolysis furnace tubes of a thermal radiation furnace operate in a furnace flame at 1100°C, requiring high safety standards. According to the safety design specifications for pyrolysis furnaces, a stable DC current of 36V or lower should be used. In contrast, the electrostatic decoking of the quench cooler tubes 8 operates in a non-thermal reaction environment below 600°C. There is no chemical reaction here; it only cools the high-temperature material and recovers heat energy to generate steam. The coking mechanism of the quench cooler is condensation coking, and the coke particles are liquid-solid mixed coke particles. Secondly, due to high safety requirements, the electro-coking process of the pyrolysis furnace using thermal radiation employs a stable DC current of 36V or lower. In contrast, the quench cooler, with its low temperature and no thermal reaction, uses a DC pulsed current of 36V or higher for electro-coking. The voltage and current characteristics of these two processes differ. While a stable DC current of 36V or lower is effective at removing solid coke particles, it is less effective at removing liquid-solid mixed coke particles. This is because liquid-solid mixed coke particles are more adhesive, requiring a higher voltage and pulsed current electro-coking process. Compared to ordinary DC and non-pulsed DC, pulsed DC can produce an effect similar to an impact rotation, generating a stronger decoking force. Furthermore, pulsed DC can generate stronger electromagnetic disturbances, hindering liquid-solid mixed coke particles from approaching the tube wall of the quench cooler. Therefore, pulsed DC is superior to ordinary DC and non-pulsed DC in its decoking effect.

[0072] In this invention, a quench cooler electrostatic precipitator process eliminates the need for a high-voltage electrostatic precipitator tower, a feature common in traditional electrostatic precipitator processes. A pulsed low-voltage electromagnetic field is applied at both the inlet and outlet of the quench cooler tube 8. The low-voltage standard is GB / T12325-2008, with a voltage below 1000V, and an effective current is set. By effectively controlling the voltage and current of the electromagnetic field, a pulsed electromagnetic field can be formed within the quench cooler tube 8. When the flow direction of tar and coke particles within the quench cooler tube 8 aligns with the direction of the electromagnetic field, the particles are more easily drawn through the tube, rather than adsorbed onto its inner surface, thus reducing carbon buildup. Therefore, this invention's quench cooler electrostatic precipitator process solves many problems inherent in traditional electrostatic precipitator processes, such as the need for constructing complex and expensive high-voltage electrostatic precipitator towers or cylinders, high-voltage discharge safety issues, inability to operate at high temperatures, and unsuitability for purifying oxygen-containing flue gas.

[0073] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0074] Example 1

[0075] 1. Conduct a blank test;

[0076] A blank test was conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg per hour without turning on the electrostatic precipitator. Before the thermal pyrolysis reaction, the quench cooler tube 8 was removed and weighed separately. The weight M1 obtained was the weight of the empty quench cooler tube 8 (2520.00 g).

[0077] Install the quench cooler tube 8, select naphtha as the pyrolysis feedstock, set the pyrolysis temperature to 820℃, the pyrolysis pressure to 0.18MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reach the set values, introduce naphtha feedstock. After the quench cooler has been running stably for 6 hours, stop introducing naphtha feedstock, purge and dry the quench cooler tube 8, remove the quench cooler tube 8 and weigh it. The weight M2 is the sum of the empty tube weight and the blank coking amount (2521.50 grams). Subtracting the weight M1 from the weight M2 gives the blank coking amount (1.50 grams).

[0078] 2. Conduct a pulse decoking test;

[0079] Then, a pulse decoking test was conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 5mA, respectively, and the pulse current frequency was set to 50Hz. The electrostatic decoking device of this invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2, and after passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. Current flowed inside the quench cooler tube 8, forming an electromagnetic field on the surface of the quench cooler tube 8. The electromagnetic field hinders positively charged coke particles from approaching the tube wall of the quench cooler, thereby slowing down the accumulation of coke particles on the tube wall and allowing them to pass through the quench cooler tube 8 as much as possible, reducing coking on the tube wall and extending the operating cycle of the quench cooler. After the quench cooler has been running for 6 hours, the naphtha feedstock is stopped, and the quench cooler tube 8 is purged and dried. The tube 8 is then removed and weighed. The weight M3 is the sum of the empty tube weight and the amount of coking removed by electro-coking (2520.50 grams). The weight M3 minus the weight M1 is the amount of coking removed compared to the amount of coking (0.50 grams). Compared to the blank coking amount (1.50 grams), this represents a reduction of 1.00 gram, a reduction rate of 66.67%, indicating a significant coking removal effect.

[0080] Example 2: Pulse decoking test with reverse current

[0081] Pulse decoking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 5mA, respectively, and the pulse current frequency was set to 50Hz. The electrostatic decoking device of this invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2, and after passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. At the same time, the reactant 10 entered the quench cooler tube 8 through the output electrode 3 and flowed out of the quench cooler tube 8 from the input electrode 2. After the quench cooler has been running stably for 6 hours, the naphtha feedstock is stopped. After purging and drying the quench cooler tube 8, the quench cooler tube 8 is removed and weighed. The weight M4 is the sum of the weight of the empty tube and the amount of coking by electrostatic removal (2522.80 grams). The weight M4 minus the weight M1 is the amount of coking by electrostatic removal compared to the amount of coking (2.80 grams). Compared to the blank coking amount (1.50 grams), it increased by 1.30 grams, an increase of 86.67%. Not only was there no coking effect, but the amount of coking was significantly increased.

[0082] Example 3: Pulse decoking test at different voltages

[0083] Pulse decoking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, and the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 72V and 5mA, respectively, and the pulse current frequency to 50Hz. The electrostatic decoking device of this invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler furnace tube 8 through the input electrode 2, and after passing through the quench cooler furnace tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. At the same time, the reactant 10 entered the quench cooler furnace tube 8 through the input electrode 2 and flowed out of the quench cooler furnace tube 8 from the output electrode 3. After the quench cooler has been running stably for 6 hours, the naphtha feedstock is stopped. After purging and drying the quench cooler tube 8, the quench cooler tube 8 is removed and weighed. The weight M5 is the sum of the weight of the empty tube and the amount of coking by electrostatic removal (2520.45 grams). The weight M5 minus the weight M1 is the amount of coking by electrostatic removal compared to the amount of coking (0.45 grams). Compared to the amount of coking by blank (1.50 grams), it is reduced by 1.05 grams, a reduction rate of 70.00%. Compared to the coking voltage of 48V, the coking effect of the 72V coking voltage is further improved.

[0084] Example 4: Pulse decoking test with different currents

[0085] Pulse decoking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 10mA, respectively, and the pulse current frequency was set to 50Hz. The electrostatic decoking device of this invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler furnace tube 8 through the input electrode 2. After passing through the quench cooler furnace tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. At the same time, the reactant 10 entered the quench cooler furnace tube 8 through the input electrode 2 and flowed out of the quench cooler furnace tube 8 from the output electrode 3. After the quench cooler has been running stably for 6 hours, the naphtha feedstock is stopped. After purging and drying the quench cooler tube 8, the quench cooler tube 8 is removed and weighed. The weight M6 is the sum of the weight of the empty tube and the amount of coking by electrostatic removal (2520.35 grams). The weight M6 minus the weight M1 is the amount of coking by electrostatic removal compared to the amount of coking (0.35 grams). Compared to the blank coking amount (1.50 grams), it is reduced by 1.15 grams, a reduction rate of 76.67%. Compared to the 5mA coking current, the 10mA coking current further improves the coking effect.

[0086] Example 5: Pulse defocusing test at different frequencies

[0087] Pulse decoking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 5mA, respectively, and the pulse current frequency was set to 100Hz. The electrostatic decoking device of this invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2, and after passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. At the same time, the reactant 10 entered the quench cooler tube 8 through the input electrode 2 and flowed out of the quench cooler tube 8 from the output electrode 3. After the quench cooler has been running stably for 6 hours, the naphtha feedstock was stopped. The quench cooler tube 8 was then purged and dried. The quench cooler tube 8 was then removed and weighed. The weight M7 was the sum of the weight of the empty tube and the amount of coking removed by electrostatic precipitation (2520.65 grams). The weight M7 minus the weight M1 was the amount of coking removed by electrostatic precipitation compared to the amount of coking (0.65 grams). Compared to the amount of coking in blank tube (1.50 grams), the amount of coking was reduced by 0.85 grams, a reduction rate of 50.00%. Compared to the 50Hz decoking frequency, the decoking effect of the 100Hz decoking frequency was significantly reduced. This is related to the fact that the higher the frequency of the pulse current, the closer its current characteristics are to those of no pulse current.

[0088] Example 6: Pulseless decoking test

[0089] Coking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, and the pyrolysis temperature was set at 820℃, the pyrolysis pressure at 0.18 MPa, and the pyrolysis dilution ratio at 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 5mA, respectively, with the current being a pulse-free DC current. The electrostatic decoking device of this invention was started, meaning the current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2. After passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. Simultaneously, the reactant 10 entered the quench cooler tube 8 through the input electrode 2 and flowed out of the quench cooler tube 8 from the output electrode 3. After the quench cooler has been running stably for 6 hours, the naphtha feedstock is stopped. After purging and drying the quench cooler tube 8, the quench cooler tube 8 is removed and weighed. The weight M8 is the sum of the weight of the empty tube and the amount of coking by electrostatic removal (2521.05 grams). The weight M8 minus the weight M1 is the amount of coking by electrostatic removal compared to the amount of coking (1.05 grams). Compared to the amount of coking by blank tube (1.50 grams), it is reduced by 0.45 grams, a reduction rate of 30.00%. Compared to the pulsed DC current of 48V and 5mA, the coking effect of the tube without pulsed DC current is significantly reduced.

[0090] Example 7: Decoction Test Using Alternating Current

[0091] Coking tests were conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 10mA, respectively, with the current being 50Hz AC. The electrostatic decoking device of this invention was then started. The current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2. After passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. Simultaneously, the reactant 10 entered the quench cooler tube 8 through the input electrode 2 and flowed out of the quench cooler tube 8 from the output electrode 3. After the quench cooler had been running stably for 6 hours, the naphtha feedstock was stopped. The quench cooler tubes 8 were then purged and dried. They were then removed and weighed. The weight M9 was the sum of the empty tube weight and the amount of coking removed by the electrostatic precipitator (2521.48 grams). Subtracting weight M1 from weight M9 gives the amount of coking removed compared to the amount of coke deposited (1.48 grams). This is 0.02 grams less than the amount of coke deposited in the blank (1.50 grams), which is roughly equivalent to the amount of coke deposited in the blank, indicating virtually no coking effect. This demonstrates that the coking effect of the forward current cancels out the negative effect of the reverse current on coking, resulting in no coking effect whatsoever.

[0092] Example 8: Comparative Test of Decoking Yield of Pyrolysis Products

[0093] To investigate whether the electrostatic decoking device of the present invention affects the yield of pyrolysis products while suppressing coke, a decoking test was conducted on a simulated pyrolysis pilot plant with a feed rate of 5 kg / hour. Naphtha was selected as the pyrolysis feedstock, the pyrolysis temperature was set to 820℃, the pyrolysis pressure to 0.18 MPa, and the pyrolysis dilution ratio to 0.5. After all other process parameters reached their set values, naphtha feedstock was introduced. The voltage and current output of the current conversion controller 1 were set to 48V and 5mA, respectively, and the pulse current frequency to 50Hz. The electrostatic decoking device of the present invention was started, that is, the current output by the current conversion controller 1 entered the quench cooler tube 8 through the input electrode 2, and after passing through the quench cooler tube 8, the current flowed out through the output electrode 3 or the grounding wire, forming a closed loop. At the same time, the reactant 10 entered the quench cooler tube 8 through the input electrode 2 and flowed out of the quench cooler tube 8 from the output electrode 3. After the quench cooler has been running stably for 3 hours, the naphtha feedstock is stopped. The cracking products are collected at the outlet of the quench cooler tube 8 for chromatographic analysis. The comparison data of the cracking product yields under loaded electrostatic decoking and blank conditions are shown in Table 1.

[0094] Table 1. Mass yield of pyrolysis products from electrostatic decoking and blank samples.

[0095]

[0096]

[0097] As can be seen from Table 1, the yields of pyrolysis products in the blank group and the electrostatic precipitator group are very close. This indicates that the electrostatic precipitator of the present invention has virtually no impact on the yield of pyrolysis products.

[0098] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A quench cooler electrostatic decoking process, characterized in that, This is achieved using a quench cooler electrostatic precipitator, which includes: A pulse power supply; the voltage range of the pulse power supply is 37V~380V; the current range of the pulse power supply is 1mA~10mA; the frequency range of the DC pulse current is 5Hz~60Hz; A current conversion controller connected to a pulse power supply; the current conversion controller converts ordinary alternating current into pulsed direct current; The input electrode and output electrode are respectively connected to the current conversion controller; the input electrode is connected to the inlet end of the quench cooler furnace tube, and the output electrode is connected to the outlet end of the quench cooler furnace tube; the current conversion controller applies the set voltage and current to both ends of the quench cooler furnace tube through the input electrode and the output electrode, thereby forming an electromagnetic field in the quench cooler furnace tube; the flow direction of the reactant material in the quench cooler furnace tube is the same as the flow direction of the current. An input detection electrode and an output detection electrode are respectively connected to the furnace tube of the quench cooler; the input detection electrode is connected to the inlet end of the furnace tube of the quench cooler, and the output detection electrode is connected to the outlet end of the furnace tube of the quench cooler; the input detection electrode and the output detection electrode detect the voltage across the furnace tube of the quench cooler in real time. A detector that is connected to the input detection electrode and the output detection electrode respectively; The process includes the following steps: The reactants containing tar and coke particles from the radiant furnace tubes enter the quench cooler. Within the quench cooler tubes, the reactants move at high speed along with other gaseous hydrocarbons, causing the tar and coke particles to acquire a positive charge, while the other gaseous hydrocarbons acquire a negative charge. According to Coulomb's law of electromagnetism, there is an interaction force between different charges. The positively charged tar and coke particles, attracted by electrostatic forces, detach from the reactants and adsorb onto the inner surface of the quench cooler tubes, continuously accumulating. When the electrostatic decoking device in the quench cooler is activated, current flows through the quench cooler tubes, creating an electromagnetic field on their surface. When the flow direction of the tar and coke particles within the quench cooler tubes aligns with the direction of the electromagnetic field, the field hinders the positively charged tar and coke particles from approaching the tube wall, slowing their accumulation on the tube wall and allowing them to pass through the quench cooler tubes. This reduces the accumulation time on the tube wall and extends the quench cooler's operating cycle.

2. The electrostatic decoking process for a quench cooler according to claim 1, characterized in that, The input electrode, output electrode, input detection electrode, and output detection electrode are all made of nickel-based high-temperature alloys, titanium-based high-temperature alloys, or molybdenum-based high-temperature alloys.

3. The electrostatic decoking process for a quench cooler according to claim 1, characterized in that, The input electrode, output electrode, input detection electrode, and output detection electrode are all equipped with cooling radiators.

4. The electrostatic decoking process for a quench cooler according to claim 3, characterized in that, The cooling radiator is an active cooling structure or a passive cooling structure; the active cooling structure is an air-cooled cooling structure or a water-cooled cooling structure; the passive cooling structure is a finned cooling structure or a microchannel cooling structure.

5. The electrostatic decoking process for a quench cooler according to claim 1, characterized in that, The cross-sections of the input electrode, output electrode, input detection electrode, and output detection electrode are all circular, square, or triangular; the end faces of the input electrode, output electrode, input detection electrode, and output detection electrode are all planar or curved surfaces.

6. The electrostatic decoking process for a quench cooler according to claim 1, characterized in that, The current output by the current conversion controller enters the quench cooler tube through the input electrode and flows out of the quench cooler tube through the output electrode, forming a closed loop.

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