Catalytic cracking process charring tank regeneration system and method

Abstract

The invention provides a catalytic cracking process charring tank regeneration system and a catalytic cracking process charring tank regeneration method. The regeneration system comprises a catalytic cracking process charring tank regenerator (11) and an external heat compensation device (1), the external heat compensation device (1) comprises an electric energy supply heating device (2) and a shell (3); the electric energy supply heating device (2) consists of a plurality of electric heating pipes (4); the external heat compensation device (1) further comprises a first catalyst conveying channel (5) and a second catalyst conveying channel (6) which are used for being communicated with a regenerator of a catalytic cracking process charring tank. The first catalyst conveying channel (5) is arranged at the upper part of the external heat compensation device (1), and the second catalyst conveying channel (6) is arranged at the lower part of the external heat compensation device (1); the external heat compensation device (1) is communicated with the catalytic cracking process charring tank regenerator (10) through a first catalyst conveying channel (5) and a second catalyst conveying channel (6).

Description

Technical Field

[0001] The present invention relates to the field of chemical industry, and in particular to a system and method for regenerating a coke drum in a catalytic cracking process. Background Art

[0002] Saturated hydrocarbon feedstocks with high paraffin content are ideal for catalytic cracking to produce light olefins. The carbon-carbon bonds of paraffins are relatively weak, and they are more likely to break after absorbing a large amount of heat energy during the cracking process, forming light olefins. In contrast, aromatic carbon in the feedstock will only undergo condensation reactions to form coke during the catalytic cracking process. These cokes will be deposited on the catalyst surface and burn during regeneration to release heat and carbon dioxide. As future environmental regulations will become increasingly stringent on carbon emissions, feedstocks with high aromatic carbon content will inevitably be restricted.

[0003] However, limiting the use of feedstocks with high aromatic carbon content means that the heat released during catalyst regeneration will not be sufficient to maintain the thermal balance of the reaction-regeneration system, and external heat supplementation is required to meet the needs of reaction and regeneration. Traditional methods of relying on fossil fuels for heat supplementation will increase carbon dioxide emissions. In order to meet this challenge, electric heating devices have become the optimal choice. Using electric heating devices to enhance heat transfer is one of the effective ways to increase the production of low-carbon olefins and reduce carbon emissions.

[0004] Invention patent application CN200510017540.1 discloses a method for heating or supplementing heat in a hydrocarbon processing device reaction system, in which coal powder with a particle size of 10-140 μm is continuously or intermittently added to a catalyst regenerator through an automatic catalyst replenishment system and / or a catalyst promoter addition system. This method will cause the regenerated flue gas to contain more solid impurity particles, increasing the difficulty of subsequent treatment of the regenerated flue gas, and the combustion of coal powder will additionally increase a large amount of carbon dioxide emissions.

[0005] The invention patent application CN201510833567.1 discloses a reheater, a catalytic cracking regeneration device and an external heat supplement method, in which the reheater is arranged next to the catalyst regenerator and connected to the catalyst through a catalyst delivery pipeline to form a cycle. Diesel or heavy oil with an auto-ignition point below 380°C is burned in the reheater to form uniform additional coke on the surface of the catalyst, which is then sent to the regenerator for complete combustion and heat release. However, the large amount of water vapor produced by the combustion of oil products will create a high-temperature hydrothermal environment and accelerate the deactivation of the regeneration agent. Moreover, the heat supplement caused by the combustion of oil products can easily cause the local temperature of the catalyst to be too high, exceeding 1000°C, resulting in the collapse of the regeneration agent pores and the breakage of particles, reducing the stability and life of the catalyst.

[0006] In addition, there are currently some internal and external heat supplement equipment, which are heat supplement equipment installed inside and outside the regenerator respectively. The internal heat supplement equipment is installed in the regenerator bed or the main air duct. Since the heater lacks shell protection, it is easy to break under the action of the main air or fluidized medium, and the regenerator bed or main air has a small heat capacity, and the heat exchange efficiency between the heater and the heater is low, which makes it difficult to ensure safety and cannot be used efficiently for a long period of time; the external heat supplement equipment is installed outside the regenerator, and a lifting riser structure is used to draw out the catalyst from a certain bed of the regenerator. After being heated by the external heat supplement equipment, it returns to the same bed. However, the bed density of the catalyst in the external heat supplement equipment is not considered to ensure sufficient heat capacity to achieve efficient heat transfer, and there is also a lack of circulation of the catalyst between the external heat supplement equipment and the regenerator, and it is impossible to ensure that the catalyst temperature of 700-800°C in the regenerator is achieved.

[0007] The bed regenerator is a commonly used dense phase fluidized bed regeneration method in catalytic cracking units. Its low operating linear velocity and high degree of back mixing make it close to a fully mixed flow operation state. When the coke content on the catalyst is low, the heat released by the combustion of coke is difficult to maintain the regeneration temperature, and it is necessary to supplement heat outside the regeneration unit. The main problems with current technologies are that they all increase the carbon dioxide emissions of the device, and the high-temperature hydrothermal environment accelerates the deactivation and breakage of the catalyst; or the electric heating equipment used does not take into account the catalyst bed density and catalyst circulation volume in the equipment, making it difficult to achieve the heating effect of the regenerator. In the current context, it is necessary to provide a more environmentally friendly and efficient heat supplement method to optimize the catalytic cracking process. Summary of the invention

[0008] One object of the present invention is to provide a catalytic cracking process coke drum regeneration system;

[0009] Another object of the present invention is to provide a method for supplementing heat for a coke drum regenerator in a catalytic cracking process.

[0010] To achieve the above-mentioned objectives, on the one hand, the present invention provides a catalytic cracking process burnt drum regeneration system, wherein the regeneration system includes a catalytic cracking process burnt drum regenerator 11 and an external heat supplement device 1; the external heat supplement device 1 includes an electric power supply heating device 2 and a shell 3; the electric power supply heating device 2 is composed of a plurality of electric heating tubes 4; the external heat supplement device 1 also includes a first catalyst delivery channel 5 and a second catalyst delivery channel 6 for communicating with the catalytic cracking process burnt drum regenerator; the first catalyst delivery channel 5 is arranged at the upper part of the external heat supplement device 1, and the second catalyst delivery channel 6 is arranged at the lower part of the external heat supplement device 1; the external heat supplement device 1 is connected to the catalytic cracking process burnt drum regenerator 11 through the first catalyst delivery channel 5 and the second catalyst delivery channel 6.

[0011] According to some specific embodiments of the present invention, the number of the electric heating tubes 4 is 2-50.

[0012] According to some specific embodiments of the present invention, the number of the electric heating tubes 4 is 5-40.

[0013] According to some specific embodiments of the present invention, the number of the electric heating tubes 4 is 10-30.

[0014] According to some specific embodiments of the present invention, the electric heating tubes 4 are arranged in clusters.

[0015] According to some specific embodiments of the present invention, the electric heating tube 4 is fixedly installed on the flange cover 10 of the external heating device 1.

[0016] According to some specific embodiments of the present invention, the electric heating tubes 4 are connected in parallel.

[0017] The electric heating tubes 4 are controlled separately through external control circuits to realize heating of the electric heating tubes one by one, partially or completely.

[0018] The heating power of each electric heating tube 4 is the same, and the total heating power is equal to the total power of the electrically powered heating device 2 .

[0019] According to some specific embodiments of the present invention, the electric heating tube 4 includes a heating tube shell 41 , an electric heating component 42 arranged inside the heating tube shell, and fins 43 arranged on the outer surface of the heating tube shell 41 .

[0020] According to some specific embodiments of the present invention, the electric heating component 42 is required to withstand 1400°C.

[0021] According to some specific embodiments of the present invention, the heating tube shell 41 is a ceramic heating tube shell.

[0022] According to some specific embodiments of the present invention, the ceramic heating tube shell can withstand a high temperature exceeding 1200° C. for a long period of time.

[0023] The present invention uses ceramic material to make the outer shell of the heating tube. The high hardness of the ceramic material solves the problem that the outer surface of the electric heating tube 4 needs to withstand high wear resistance for a long time under high temperature and catalyst fluidization conditions.

[0024] According to some specific embodiments of the present invention, the fins 43 are spirally arranged around the heating tube shell 41 from top to bottom.

[0025] According to some specific embodiments of the present invention, the spiral angle of the fin 43 is 30°-60°.

[0026] According to some specific embodiments of the present invention, the width of the fin 43 is 0.1-1.0 times the diameter of the heating tube shell 41 .

[0027] The fins of the present invention increase the disturbance of catalyst particles in the external heating device and the heat transfer area, thereby improving the heating efficiency of the electric power supply heating device.

[0028] According to some specific embodiments of the present invention, the electric heating tube 4 further includes a temperature sensor and an over-temperature protection component 44 arranged inside the heating tube housing 41 .

[0029] According to some specific embodiments of the present invention, a horizontal turning structure 7 is provided inside the first catalyst delivery channel 5 at the connection with the external heat supply device 1 .

[0030] According to some specific embodiments of the present invention, the angle between the horizontal turning structure 7 and the conveying channel 5 is 30 degrees to 60 degrees.

[0031] According to some specific embodiments of the present invention, the height h of the horizontal turning structure 7 is ( Figure 1 h) is smaller than the pipe diameter ( Figure 1 1 / 4 of R in.

[0032] According to some specific embodiments of the present invention, a valve 8 is provided on the second catalyst delivery channel 6 .

[0033] According to some specific embodiments of the present invention, the valve 8 is a sliding valve.

[0034] According to some specific embodiments of the present invention, the external heat supplement device 1 is provided with a catalyst fluidization distributor 9 at the bottom of the inner cavity.

[0035] According to some specific embodiments of the present invention, 1-2 external heating devices 1 are provided.

[0036] According to some specific embodiments of the present invention, there are two external heat supplement devices 1, which are symmetrically arranged on both sides of the catalytic cracking process coke drum regenerator 11.

[0037] According to some specific embodiments of the present invention, two external heat supplement devices 1 are provided and are symmetrically distributed on both sides of the catalytic cracking process coke drum regenerator 5 .

[0038] On the other hand, the present invention also provides a method for supplementing heat to a catalytic cracking process burnt drum regenerator, wherein the method comprises supplementing heat to the catalytic cracking process burnt drum regenerator using any of the external heat supplement devices described above in the present invention.

[0039] According to some specific embodiments of the present invention, the linear velocity of the fluidizing gas in the external supplemental heat device 1 is 0.05-1 m / s.

[0040] According to some specific embodiments of the present invention, the linear velocity of the fluidizing gas in the external supplemental heat device 1 is 0.1-0.4 m / s.

[0041] According to some specific embodiments of the present invention, the linear velocity of the fluidizing gas in the external supplemental heat device 1 is 0.2-0.3 m / s.

[0042] According to some specific embodiments of the present invention, the operating temperature in the external heat supply device 1 is 650-950°C.

[0043] According to some specific embodiments of the present invention, the operating temperature in the external heat supply device 1 is 700-850°C.

[0044] According to some specific embodiments of the present invention, the operating temperature in the external heat supply device 1 is 800-820°C.

[0045] According to some specific embodiments of the present invention, the catalyst bed density in the external heating device 1 is 200-700 kg / m 3 .

[0046] According to some specific embodiments of the present invention, the catalyst bed density in the external heating device 1 is 300-650 kg / m 3 .

[0047] According to some specific embodiments of the present invention, the catalyst bed density in the external heating device 1 is 600-650 kg / m 3 .

[0048] According to some specific embodiments of the present invention, the circulation amount of catalyst between the external heat supplement device 1 and the catalytic cracking process coke drum regenerator is 0.05 to 1.0 times the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

[0049] According to some specific embodiments of the present invention, the circulation amount of catalyst between the external heat supplement device 1 and the catalytic cracking process coke drum regenerator is 0.1 to 0.5 times the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

[0050] According to some specific embodiments of the present invention, the circulation amount of catalyst between the external heat supplement device 1 and the catalytic cracking process coke drum regenerator is 0.25 to 0.35 times the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

[0051] The catalytic cracking regeneration system of the present invention comprises a catalytic cracking bed regeneration system and a catalytic cracking reaction system (such as a riser reactor or a turbulent fluidized bed reactor).

[0052] The catalytic cracking bed regeneration system and the catalytic cracking reaction system can be conventional catalytic cracking bed regeneration system and catalytic cracking reaction system in the art.

[0053] According to some specific embodiments of the present invention, the heat compensation coefficient of the external heat compensation device 1 is 0.05-5.0.

[0054] According to some specific embodiments of the present invention, the heat compensation coefficient of the external heat compensation device 1 is 0.5-2.

[0055] According to some specific embodiments of the present invention, the operating temperature in the external supplementary heat device 1 is 800-820°C, the linear velocity of the fluidizing gas in the external supplementary heat device 1 is 0.2-0.3 m / s, and the catalyst bed density in the external supplementary heat device 1 is 600-650 kg / m 3 The circulation amount of catalyst between the external heat supplement device 1 and the catalytic cracking process coke drum regenerator is 0.25 to 0.35 times the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

[0056] According to some specific embodiments of the present invention, the operating temperature in the external supplementary heat device 1 is 800°C, the linear velocity of the fluidizing gas in the external supplementary heat device 1 is 0.24 m / s, and the catalyst bed density in the external supplementary heat device 1 is 650 kg / m 3 The circulation amount of catalyst between the external heat supplement device 1 and the catalytic cracking process coke drum regenerator is 0.30 times the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

[0057] The total heat supplement of the external heat supplement device 1 of the present invention = heat supplement coefficient * (heat requirement of catalytic cracking reactor - heat of coke combustion); the combustion heat of coke = coke combustion enthalpy × raw material processing volume × coke yield; the total power of the electric power supply heating device 2 of the external heat supplement device 1 is equal to the total heat supplement of the external heat supplement device per unit time.

[0058] In summary, the present invention provides a device, system and method for external heat supplementation of a coke drum regenerator in a catalytic cracking process. The device of the present invention has the following advantages:

[0059] An electrically powered external heating device is used to provide external heating for the regenerated catalyst. No hydrothermal environment is generated in the external heating device, and structural deactivation of the catalyst can be avoided even under overheating conditions, thereby reducing catalyst consumption and achieving heat balance in the catalytic cracking reaction-regeneration system.

[0060] By using electricity to supply heat to the regenerated catalyst, instead of adding fuel oil or coal powder to burn to supplement heat, there is no additional carbon dioxide emission;

[0061] The present invention can efficiently transfer the heat energy converted from electrical energy to the regenerator and the catalytic cracking reactor by flexibly adjusting the catalyst bed density and the catalyst circulation multiple of the external heat supplement device, thereby realizing high-temperature regeneration of the catalyst to be regenerated and improving the efficiency of heat supplement to achieve energy saving effect.

[0062] The present invention uses an external heating device equipped with an electric heating tube bundle, which can quickly and accurately control the temperature of the catalyst in the regenerator by adjusting the current or voltage, and flexibly adjust the process conditions of the reactor;

[0063] The present invention arranges the supplementary heat device outside the regenerator, which can prevent the supplementary heat device from aging at high temperature, avoid the influence of the failure of the supplementary heat device on the regenerator, ensure the safe use of the equipment, and significantly extend the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 This is a schematic diagram of the external heat supplement device and the catalytic cracking process coke drum regeneration system of Example 1 of the present invention.

[0065] Figure 2 It is an enlarged schematic diagram of the electric heating tube of Example 1 of the present invention. DETAILED DESCRIPTION

[0066] The implementation process of the present invention and the beneficial effects produced are described in detail below through specific embodiments, which is intended to help readers better understand the essence and characteristics of the present invention, and is not intended to limit the scope of implementation of the present invention.

[0067] Example 1

[0068] Using industrial production equipment, according to Figure 1 The external heat supplement device of the catalytic cracking process burnt drum regenerator shown in the figure uses electric energy to supplement heat. The external heat supplement device includes: an external heat supplement device 1 with an electric energy heating device 2 and a catalyst fluidizing distributor 9 arranged inside, a first catalyst delivery channel 5 and a second catalyst delivery channel 6 for delivering catalyst into and out of the external heat supplement device 1, a horizontal turning structure 7 at the outlet end of the first catalyst delivery channel 5 and a slide valve 8 on the second catalyst delivery channel 6, and a catalytic cracking process burnt drum regenerator 11.

[0069] The catalyst coming out of the catalytic cracking process coke tank regenerator 11 enters the external heating device 1 through the first catalyst delivery channel 5 and the horizontal turning structure 7 at the outlet of the first catalyst delivery channel 5, and under the action of the catalyst fluidizing distributor 9 in the external heating device, a uniformly distributed catalyst particle bed is formed to fully exchange heat with the electric power supply heating device 2. The linear velocity of the fluidizing gas in the external heating device 1 is 0.25m / s; the operating temperature in the external heating device 1 is 750℃; the density of the catalyst bed is 400kg / m by adjusting the linear velocity of the fluidizing gas in the external heating device 1. 3 By adjusting the opening of the slide valve 8 on the second catalyst delivery channel 6, the circulation amount of the catalyst between the external heat supply device 1 and the catalytic cracking process coke tank regenerator 11 is 0.45 times the circulation amount of the catalyst in the catalytic cracking reverse regeneration system.

[0070] Taking a catalytic cracking unit for producing low-carbon olefins with a processing capacity of 200 tons / h of light hydrocarbons as an example, the coke yield is 3.20% (mass fraction), and the amount of coke burned in the regenerator per hour is 6.40 tons. The heat released by the combustion of coke is 2.30*10 8 kJ / h. The catalytic cracking reactor requires 6.41*10 8 kJ / h, in order to maintain the heat balance of the reaction-regeneration system of the catalytic cracking unit, the heat supplement coefficient is preferably 1.2, and the total heat supplement of the external heat supplement device 1 = 1.2*(heat required by the catalytic cracking reactor - heat of coke combustion) = 4.932*10 8 kJ / h, the total power of the external heating device 1 is 137.01MW.

[0071] According to the total power of the external heating device 1, 30 electric heating tubes are set, and the power of each electric heating tube is 4.567MW. The electric heating tubes are connected in parallel and controlled separately by external control circuits to realize the electric heating tubes being powered on one by one, partially or completely for heating. Figure 2 As shown, each electric heating tube 4 contains an electric heating component 42, a temperature sensor and an over-temperature protection component 44, and the electric heating component is required to withstand 1400°C; in order to solve the problem of wear on the outer surface of the electric heating tube 4 under high temperature and catalyst fluidization state, the outside of the electric heating tube 4 is a ceramic heating tube shell 41; the ceramic heating tube shell 41 outside the electric heating tube 4 can be provided with fins 43 (the spiral angle is 32°, and the width is 0.15 times the diameter of the heating tube shell 41) to increase the disturbance of the catalyst particles in the supplementary heat device and the heat transfer area, thereby improving the heating efficiency of the electric power heating device.

[0072] The working conditions in the external heating device 1 of Example 1 are shown in Table 1:

[0073] Table 1 Main working conditions of external heating device

[0074] Example 1 Comparative Example 1 Heater pressure, MPa(A) 0.30 0.33 Heater operating temperature, ℃ 750 680 Gas linear velocity, m / s 0.25 0.25 Oxygen content in outlet flue gas, v% No smoke generation 0.5 Fuel to catalyst ratio No fuel used 1:6-500 Will it increase carbon dioxide emissions? none have

[0075] It can be seen from the data in Table 1 that Example 1 and the comparative example data in Table 1 are from invention patent CN201510833567.1. Compared with other current reheater methods (reheater, catalytic cracking regeneration device and external heat supply method. Invention patent CN201510833567.1), the use of an electrically powered reheater to externally heat the regenerated catalyst can enable the reheater to operate at a higher temperature, and no hydrothermal environment is generated in the reheater, no smoke is generated, and no additional carbon dioxide emissions are emitted.

[0076] Example 2

[0077] Using the experimental pilot plant, according to Figure 1 The external heat supplement device of the catalytic cracking process burnt drum regenerator shown in the figure uses electric energy to supplement heat. The external heat supplement device includes: an external heat supplement device 1 with an electric energy heating device 2 and a catalyst fluidizing distributor 9 arranged inside, a first catalyst delivery channel 5 and a second catalyst delivery channel 6 for delivering catalyst into and out of the external heat supplement device 1, a horizontal turning structure 7 at the outlet end of the first catalyst delivery channel 5 and a slide valve 8 on the second catalyst delivery channel 6, and a catalytic cracking process burnt drum regenerator 11.

[0078] The catalyst coming out of the catalytic cracking process coke tank regenerator 11 enters the external heating device 1 through the first catalyst delivery channel 5 and the horizontal turning structure 7 at the outlet end of the first catalyst delivery channel, and under the action of the catalyst fluidization distributor 9 in the external heating device 1, a uniformly distributed catalyst particle bed is formed to fully exchange heat with the electric power supply heating device 2. The linear velocity of the fluidizing gas in the external heating device 1 is 0.35m / s; the operating temperature in the external heating device 1 is 800℃; the density of the catalyst bed is 550kg / m by adjusting the linear velocity of the fluidizing gas in the external heating device 1. 3 By adjusting the opening of the slide valve 8 on the second catalyst delivery channel 6, the circulation amount of the catalyst between the external heat supply device 1 and the catalytic cracking process coke tank regenerator 11 is 0.1 times the circulation amount of the catalyst in the catalytic cracking reverse regeneration system.

[0079] Taking the pilot plant of catalytic cracking to produce light olefins with a processing capacity of 15 kg / h naphtha as an example, the coke yield is 3.68% (mass fraction), and the amount of coke burned in the regenerator per hour is 0.5595 kg. The heat released by the coke combustion is 2.01*10 4 kJ / h. The catalytic cracking reactor requires 4.14*10 4 kJ / h, in order to maintain the heat balance of the catalytic cracking device reaction-regeneration system, the heat supplement coefficient is preferably 2.0, and the total heat supplement of the external heat supplement device 1 = 2.0*(heat required by the catalytic cracking reactor - heat of coke combustion) = 4.26*104 kJ / h, the total power of the external heating device 1 is 11.83MW.

[0080] According to the total power of the external heating device 1, 10 electric heating tubes are set, and the power of each electric heating tube is 1.2MW. The electric heating tubes are connected in parallel and controlled separately by external control circuits to realize the heating of the electric heating tubes one by one, partially or completely. Each electric heating tube 4 contains an electric heating component 42, a temperature sensor and an over-temperature protection component 44. The electric heating component is required to withstand 1400°C; in order to solve the problem of wear on the outer surface of the electric heating tube 4 under high temperature and catalyst fluidization state, the outside of the electric heating tube 4 is a ceramic heating tube shell 41; the ceramic shell 41 outside the electric heating tube 4 can be provided with fins 43 (the spiral angle is 40°, and the width is 0.20 times the diameter of the heating tube shell 41) to increase the disturbance of the catalyst particles in the heater and the heat transfer area, thereby improving the heating efficiency of the electric power heating device.

[0081] In view of the fact that catalytic cracking is a deep catalytic cracking reaction mode, in order to compare the effect of Example 2 on the catalyst and product yield, other current heat supplementation methods (a catalyst regeneration method and equipment for supplementing the heat of a catalytic cracking unit. Invention patent CN201110272641.9) are selected. The data of the comparative examples in Table 2-4 are from the invention patent CN201110272641.9. Example 2 was used in a pilot plant for catalytic cracking of light olefins with a processing capacity of 15kg / h naphtha for testing, and naphtha was also used as the catalytic cracking raw material. The raw material properties are shown in Table 2. Compared with the comparative example, the properties of the raw material of Example 2 are slightly worse, which is manifested in a slightly lower content of paraffins and a higher content of aromatics.

[0082] Table 2 Naphtha raw material properties

[0083] Example 2 Comparative Example 2 <![CDATA[Density (20 °C), g / cm 3 > 0.7387 0.7358 Vapor pressure, kPa 49.5 50.0 Group composition, w% Alkanes 49.92 51.01 Cycloalkanes 38.23 38.24 Olefins 0.12 0.12 Aromatics 11.73 10.52 Distillation range,℃ IBP 47 46 10％ 89 87 30％ 110 107 50％ 121 120 70％ 135 133 90％ 152 149 95％ 157 155

[0084] Table 3 is a comparison of catalyst properties. Since no hydrothermal environment is generated in the supplementary heat vessel, structural deactivation of the catalyst can be avoided even under overheating conditions. Therefore, the pore volume and specific surface area of ​​the catalyst in Example 2 are significantly increased compared with those in the comparative example, and the proportion of catalyst particles smaller than 40 um is significantly reduced, which is beneficial to improving the effect of the catalytic cracking reaction.

[0085] Table 3 Catalyst properties

[0086]

[0087]

[0088] Table 4 is a comparison of operating conditions and product distribution. The regenerated catalyst is heated by electric energy supply instead of adding fuel oil combustion to supplement heat in the comparative example, and no additional carbon dioxide emissions are emitted. The temperature of the catalyst in the regenerator can be quickly and accurately controlled by adjusting the current or voltage, so that the regeneration temperature is significantly increased. The catalyst properties and improvements and reactor process conditions can be flexibly adjusted to significantly increase the yield of the target product ethylene + propylene.

[0089] Table 4 Operating conditions and product distribution

[0090]

[0091]

[0092] Example 3

[0093] In order to verify that the present invention can better ensure sufficient heat capacity to achieve efficient heat transfer by controlling the circulation amount of catalyst between the external heat supplement device and the catalytic cracking bed regenerator, thereby adjusting the bed density in the external heat supplement device, a single factor experimental comparison was carried out between Example 3 and Example 1 of the present invention.

[0094] Using industrial production equipment, according to Figure 1 The catalytic cracking bed regenerator shown in the figure uses an external heat supplement device for electrical energy to supplement heat. The method of Example 1 is adopted. The linear velocity of the fluidizing gas in the external heat supplement device 1 is 0.25 m / s; the operating temperature in the external heat supplement device 1 is 750°C; the density of the catalyst bed is 400 kg / m by adjusting the linear velocity of the fluidizing gas in the external heat supplement device 1. 3 By adjusting the opening of the slide valve 8 on the second catalyst delivery channel 6, the circulation amount of the catalyst between the external heat supply device 1 and the catalytic cracking process coke tank regenerator 11 is 0.45 times the circulation amount of the catalyst in the catalytic cracking reverse regeneration system. Taking the catalytic cracking unit for producing low-carbon olefins with a processing capacity of 200 tons / h of light hydrocarbons as an example, the coke yield is 3.20% (mass fraction), and the amount of coke burned in the regenerator per hour is 6.40 tons, then the heat released by the combustion of coke is 2.30*10 8 kJ / h. The catalytic cracking reactor requires 6.41*10 8 kJ / h, in order to maintain the heat balance of the catalytic cracking unit reaction-regeneration system, the heat supplement coefficient is 1.2, and the total heat supplement of the external heat supplement device 1 = 1.2*(heat required by the catalytic cracking reactor - heat of coke combustion) = 4.932*10 8 kJ / h, the total power of the external heating device 1 is 137.01MW.

[0095] Using industrial production equipment, according to Figure 1The external heating device of the catalytic cracking bed regenerator using electrical energy is used for heat supplementation, and the following method is adopted: the linear velocity of the fluidizing gas in the external heating device 1 is 0.25m / s; the operating temperature in the external heating device 1 is 750°C; the density of the catalyst bed is 600kg / m by adjusting the linear velocity of the fluidizing gas in the external heating device 1 3 By adjusting the opening of the slide valve 8 on the second catalyst delivery channel 6, the circulation amount of the catalyst between the external heat supply device 1 and the catalytic cracking bed regenerator 11 is 0.35 times the circulation amount of the catalyst in the catalytic cracking reverse regeneration system. Taking a catalytic cracking unit for producing low-carbon olefins with a processing capacity of 200 tons / h of light hydrocarbons as an example, the coke yield is 3.20% (mass fraction), and the amount of coke burned in the regenerator per hour is 6.40 tons, then the heat released by the combustion of coke is 2.30*10 8 kJ / h. The catalytic cracking reactor requires 6.41*10 8 kJ / h, in order to maintain the heat balance of the catalytic cracking unit reaction-regeneration system, the heat supplement coefficient is 1.1, and the total heat supplement of the external heat supplement device 1 = 1.1*(heat required by the catalytic cracking reactor - heat of coke combustion) = 4.525*10 8 kJ / h, the total power of the external heating device 1 is 125.69MW.

[0096] By adjusting the bed density in the external supplementary heat device through the present invention, the heating power of the supplementary heat device can be greatly reduced, and sufficient catalyst heat capacity can be guaranteed to achieve efficient heat transfer.

[0097] Comparative Example

[0098] Using industrial production equipment, according to Figure 1 The catalytic cracking bed regenerator shown in the figure uses an external heat supplement device for electrical energy to supplement heat. The linear velocity of the fluidizing gas in the external heat supplement device 1 is 0.23 m / s; the operating temperature in the external heat supplement device 1 is 750°C; the density of the catalyst bed is 150 kg / m by adjusting the linear velocity of the fluidizing gas in the external heat supplement device 1 3 By adjusting the opening of the slide valve 8 on the second catalyst delivery channel 6, the circulation amount of the catalyst between the external heat supply device 1 and the catalytic cracking process coke tank regenerator 11 is 0.1 times the circulation amount of the catalyst in the catalytic cracking reverse regeneration system. Taking the catalytic cracking light olefin production unit with a processing capacity of 200 tons / h of light hydrocarbons as an example, the coke yield is 3.20% (mass fraction), and the amount of coke burned in the regenerator per hour is 6.40 tons, then the heat released by the coke combustion is 2.30*10 8 kJ / h. The catalytic cracking reactor requires 6.41*10 8kJ / h, in order to maintain the heat balance of the catalytic cracking unit reaction-regeneration system, the heat supplement coefficient is 1.15, and the total heat supplement of the external heat supplement device 1 = 1.15*(heat required by the catalytic cracking reactor - heat of coke combustion) = 4.726*10 8 kJ / h, the total power of the external heating device 1 is 130.4MW.

[0099] Table 5 shows that the optimization of catalyst bed density and circulation volume has played a significant role in improving catalyst performance and the yield of light olefins through the data of industrial production device Example 1, Example 2 and Comparative Example 3. Among them, in Example 3, the ethylene + propylene yield reached 57.14%, which is significantly higher than other examples. The catalyst pore volume and specific surface area in the embodiment are significantly better than those in the comparative example, indicating that the optimized parameter setting significantly enhances the catalyst regeneration effect and stability. On the whole, the efficient heat supplement support provided by the external heat supplement device, especially at higher catalyst bed density and circulation volume, significantly improves the reaction efficiency and achieves energy saving effect.

[0100] Table 5 Main working conditions and product properties of external heating device

[0101]

[0102]

[0103] In the present invention, the catalysts in the embodiments and comparative examples are from the same batch of catalysts with the same parameters, and other parameters of the catalysts in industrial production are also the same. The difference between the embodiments and comparative examples is only the difference in the parameter settings of the regenerator external heat supplement device in Table 5, so as to eliminate the influence of other factors other than these parameters.

Claims

1. A catalytic cracking process coke drum regeneration system, wherein: The regeneration system comprises a catalytic cracking process burnt drum regenerator (11) and an external heat supplement device (1); the external heat supplement device (1) comprises an electric power supply heating device (2) and a shell (3); the electric power supply heating device (2) is composed of a plurality of electric heating tubes (4) (preferably 2-30 tubes); the external heat supplement device (1) also comprises a first catalyst delivery channel (5) and a second catalyst delivery channel (6) for communicating with the catalytic cracking process burnt drum regenerator; the first catalyst delivery channel (5) is arranged at the upper part of the external heat supplement device (1), and the second catalyst delivery channel (6) is arranged at the lower part of the external heat supplement device (1) (preferably a horizontal turning structure (7) is arranged inside the first catalyst delivery channel (5) at the connection with the external heat supplement device (1)) (more preferably a valve (8) is arranged on the second catalyst delivery channel (6)); the external heat supplement device (1) is connected with the catalytic cracking process burnt drum regenerator (10) through the first catalyst delivery channel (5) and the second catalyst delivery channel (6).

2. The catalytic cracking process coke drum regeneration system according to claim 1, wherein: The electric heating tube (4) comprises a heating tube shell (41) (preferably a ceramic heating tube shell), an electric heating component (42) arranged inside the heating tube shell, and fins (43) arranged on the outer surface of the heating tube shell (41) (preferably the fins (43) are arranged in a spiral arrangement around the heating tube shell (41) from top to bottom).

3. The catalytic cracking process coke drum regeneration system according to claim 2, wherein: The electric heating tube (4) also includes a temperature sensor and an over-temperature protection component (44) arranged inside the heating tube shell (41).

4. The catalytic cracking process coke drum regeneration system according to any one of claims 1 to 3, wherein: The external heat supplement device (1) is provided with a catalyst fluidizing distributor (9) at the bottom of the inner cavity.

5. The catalytic cracking process coke drum regeneration system according to any one of claims 1 to 4, wherein: There are two external heat supplement devices (1), which are symmetrically arranged on both sides of the catalytic cracking process coke drum regenerator (11).

6. A method for supplementing heat in a catalytic cracking process coke drum regenerator, wherein: The method comprises using the external heat supplement device (1) described in any one of claims 1 to 5 to supplement the heat of the catalytic cracking process coke drum regenerator (11).

7. The method according to claim 6, wherein: The linear velocity of the fluidizing gas in the external supplemental heat device (1) is 0.05-1 m / s (preferably 0.1-0.4 m / s).

8. The method according to claim 6 or 7, wherein: The operating temperature in the external supplementary heat device (1) is 650-950°C (preferably 700-850°C).

9. The method according to any one of claims 6 to 8, wherein: The catalyst bed density in the external heating device (1) is 200-700 kg / m 3 (Preferably 300 to 650 kg / m 3 ).

10. The method according to any one of claims 7 to 9, wherein: The circulation amount of catalyst between the external heat supplement device (1) and the catalytic cracking process coke drum regenerator is 0.05 to 1.0 times (preferably 0.1 to 0.5 times) the circulation amount of catalyst in the catalytic cracking reverse regeneration system.

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