A method for simulating catalytic cracking regeneration process and evaluating regeneration effect

Abstract

The present disclosure relates to a method for simulating a catalytic cracking regeneration process and evaluating the regeneration effect, comprising the following steps: determining experimental operating parameters for simulating the catalytic cracking regeneration process, wherein the experimental operating parameters include: superficial gas velocity of the coking gas, standard gas inlet quantity of the coking gas, apparent pressure in the regenerator, and particle circulation quantity of the regenerator regenerant; making the spent catalyst enter a continuous catalytic cracking regeneration operation simulation evaluation system, performing a regeneration simulation reaction under the experimental operating parameters, and collecting simulation result data; and judging whether the regeneration simulation reaction is simulated successfully according to the simulation result data. The continuous catalytic cracking regeneration process simulation can be realized, the effect of rapidly reproducing the industrial regeneration process by using a small amount of catalyst in a small and medium-sized laboratory is achieved, and thus the coking effect of the catalytic cracking regeneration process can be more accurately and conveniently evaluated.

Description

Technical Field

[0001] This disclosure relates to the chemical or petrochemical fields, specifically to a method for simulating a catalytic cracking regeneration process and evaluating the regeneration effect. Background Technology

[0002] Petroleum, as one of my country's most important resources, plays a crucial role as both fuel and raw material, supporting the development of various industries, including manufacturing, agriculture, transportation, food, pharmaceuticals, and daily chemicals. Catalytic cracking plays a pivotal role in petroleum refining, with 80% of my country's gasoline and 30% of its diesel fuel originating from this unit. The core regeneration process of catalytic cracking consists of a reaction process and a regeneration process. The reaction process primarily involves the production and refining of various products; the regeneration process regenerates the deactivated catalyst by burning coke, while simultaneously providing the heat needed to maintain the reaction temperature.

[0003] Currently, most laboratory research methods for catalytic cracking regeneration processes are intermittent simulation methods conducted using small-scale fixed fluidized bed devices, while a small number are simulation evaluation methods conducted using pilot-scale catalytic cracking devices.

[0004] Small-scale fixed fluidized bed devices operate intermittently, as exemplified by the intermittent evaluation device disclosed in CN104845661B. The experimental method and procedure involve loading different masses or types of actual materials for each experiment, changing the temperature or inlet gas composition during the experiment. The experimental format is singular, and the control method is simple, often involving setting a temperature or flow rate value and waiting for the device to automatically adjust, followed by collecting peak values ​​or single-point data corresponding to specific temperatures. This differs from actual industrial regeneration effects, serving more as a trend observation tool than a means to simulate and reproduce the real regeneration environment, and also making it difficult to provide quantitative results and recommendations.

[0005] Pilot-scale units are designed to simulate a complete catalytic cracking reaction regeneration process, focusing primarily on mimicking the reaction process. Operating parameters such as gas flow rate are adjusted according to the coking requirements on the reaction side. Compared to industrial units, this approach presents challenges such as larger gas flow rates and shallower bed depths. This results in excessively short gas residence times, making it difficult to simulate the actual pollutant generation mechanisms in regenerated flue gas. Increasing the bed depth leads to an excessively high height-to-diameter ratio, causing undesirable fluidization conditions like throttling at smaller bed diameters. Reducing the apparent gas velocity fails to provide sufficient oxygen to support coke combustion. Conversely, reducing the regenerator circulation rate to decrease oxygen demand results in excessively long solids residence times, differing from industrial regeneration units. Furthermore, pilot-scale units cannot arbitrarily adjust the internal pressure of the regenerator, as pressure changes can negatively impact the reaction in the reaction section.

[0006] To achieve continuous regeneration and closely resemble industrial-scale operations, the catalyst stockpile and circulation rate cannot be too small. In this case, the reactor needs to be started up by heating before reaching thermal equilibrium. Specifically, in the initial experimental phase, an external heater is needed to raise the reactor temperature to 500–700°C. However, because catalytic cracking regeneration is exothermic, the heat input must be gradually reduced after the reaction begins, and heat extraction must be performed when necessary to prevent overheating. In industrial settings, the displacement method for start-up results in a low proportion of active catalyst, taking several days to complete, even in medium-sized plants. Such a long preparation time and large reagent consumption are unsuitable for small-scale laboratory setups.

[0007] If the regenerator is removed separately for regeneration simulation experiments, the regenerated solid reagent needs to be removed from the bed promptly. Using gravity-based automatic discharge can easily lead to blockages. If pressure difference between the reactor and the discharge hopper is used, the lower storage hopper is a fixed-volume storage chamber, unlike the continuous discharge structure of an actual or medium-sized device. As the experiment progresses, changes in the volume within the discharge hopper will affect the internal pressure, thus impacting the reactor's discharge rate. This results in a progressively slower discharge rate and an increase in the amount of reagent remaining in the reactor.

[0008] US7749762 discloses an evaluation method for assessing catalyst regeneration and deactivation characteristics. This method allows catalysts in a small-scale evaluation fluidized bed to periodically undergo reducing and oxidizing coking atmospheres to simulate the periodic redox cycles experienced by catalysts in many industrial fluidized bed reactions with regeneration cycles. To achieve this, the evaluation device provided by this method is equipped with the oxidizing gas required for the regeneration reaction and the feedstock (e.g., hydrocarbons required for catalytic cracking) required for the reduction reaction. This is achieved by an automatic control device that periodically supplies the regeneration oxidizing gas and the reduction feedstock, and controls the required operating conditions such as temperature, pressure, and space velocity. This method is suitable for investigating the impact of periodic changes in the redox atmosphere on the long-term performance stability of catalysts or additives. However, for a single regeneration evaluation stage, it is essentially still a small-scale fluidized bed evaluation device operating intermittently, and the internal fluidization state and gas-solid two-phase flow and transport characteristics still differ significantly from those of industrial equipment.

[0009] CN104845661A discloses an intermittent evaluation device. A small amount of catalyst is placed in a simulated regenerator, and an experiment is conducted with a reaction time equal to the ideal time for industrial regeneration. Flue gas is then collected using a water displacement method and analyzed by gas chromatography-mass spectrometry. Due to the intermittent operation mode, the oxygen partial pressure, catalyst carbon content, and flue gas composition within the device are constantly changing over a wide range. In contrast, these parameters fluctuate only slightly within a smaller range during normal operation of an actual industrial device, generally remaining in a steady-state state. Furthermore, because the gas-solid fluidization state in this device differs significantly from that in an industrial device, characteristics such as the gas-solid contact mode, interphase mass transfer resistance, and particle residence time do not meet the simulation requirements. Therefore, the obtained regeneration kinetic data and catalyst regeneration performance evaluation results may differ significantly from the actual results of an industrial device. Summary of the Invention

[0010] The purpose of this disclosure is to provide a method for simulating the catalytic cracking regeneration process and evaluating the regeneration effect. This method can realize the simulation of the continuous catalytic cracking regeneration process, and achieve the effect of rapidly reproducing the industrial regeneration process in small and medium-sized laboratories with a small amount of catalyst, thereby more accurately and conveniently evaluating the coking effect of the catalytic cracking regeneration process.

[0011] To achieve the above objectives, this disclosure provides a method for simulating a catalytic cracking regeneration process and evaluating its regeneration effect, comprising the following steps: determining experimental operating parameters for simulating the catalytic cracking regeneration process, wherein the experimental operating parameters include: the apparent gas velocity of the coking gas, the standard inlet flow rate of the coking gas, the apparent pressure inside the regenerator, and the particle circulation rate of the regenerator regenerant; introducing the regenerator into a continuous catalytic cracking regeneration operation simulation evaluation system, performing a regeneration simulation reaction under the experimental operating parameters, and collecting simulation result data; determining whether the regeneration simulation reaction was successful based on the simulation result data; wherein, the continuous catalytic cracking... The cracking regeneration operation simulation and evaluation system includes a feed unit for the recycled agent and a regenerator. The regenerator includes a shell, a recycled agent inlet, a heat exchange medium internal component, a coking gas inlet, and a regenerator outlet. The heat exchange medium internal component is formed as a variable-diameter spiral coil and is coiled around the axial direction of the regenerator inside the shell. The heat exchange medium internal component includes a heat exchange medium inlet and a heat exchange medium outlet. The heat exchange medium inlet and outlet are respectively extended to the outside of the regenerator shell through pipelines, so that the heat exchange medium inside the heat exchange medium internal component exchanges heat with the material inside the regenerator shell only through the pipe wall.

[0012] Optionally, the apparent gas velocity u is within the numerical range represented by [u1, u2]; the method further includes determining u1 by the following equation (1-1) and determining u2 by the following equation (1-2):

[0013]

[0014]

[0015] Wherein, k1 is selected from any value between 0.8 and 0.9; k2 is selected from any value between 1.1 and 1.2; in equations (1-1) and (1-2), h represents the static height of the bed in the regenerator, m; U represents the apparent gas velocity of the coking gas in the industrial regenerator, m / s; H represents the static height of the bed in the industrial regenerator, m; u1 and u2 represent the apparent gas velocities of the coking gas required for the simulation experiment, m / s; u t This indicates the terminal velocity of industrial coking gas, in m / s.

[0016] Optionally, the method further includes determining the standard intake volume in the experimental operating parameters by means of the following equation (2):

[0017]

[0018] Where Q represents the standard intake volume, m 3 / s; d represents the inner diameter of the dense phase section of the regenerator, in meters; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 C c The carbon content of the pre-regenerating agent is expressed as wt%; r represents the volume concentration of oxygen in the flue gas from the industrial regeneration process, expressed as volume%; e represents the volume ratio of carbon monoxide to carbon dioxide in the industrial regeneration flue gas; f represents the hydrogen-to-carbon molar ratio on the pre-regenerating agent; t s C represents the average residence time of particles in an industrial regenerator, in seconds. CO2 This indicates the volume concentration of CO2 in the regenerated flue gas.

[0019] Optionally, the method further includes determining the apparent pressure within the regenerator in the experimental operating parameters by means of the following equation (3):

[0020]

[0021] Where p represents the required apparent pressure within the regenerator, in MPa; T represents the bed temperature inside the industrial regenerator, in °C; d represents the inner diameter of the dense phase section within the regenerator, in meters; u represents the apparent gas velocity of the coking gas in the simulation experiment, in m / s; and Q represents the standard inlet flow rate of the coking gas, in cubic meters per second. 3 / s.

[0022] Optionally, the method further includes determining the particle circulation rate of the regenerant in the experimental operating parameters by means of the following equation (4):

[0023]

[0024] Where S' represents the required particle circulation rate of the regenerator, g / s; h represents the static bed height of the regenerator, m; d represents the inner diameter of the dense phase section of the regenerator, m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 ;t s The average residence time of particles in the industrial regenerator is expressed in seconds; optionally, the particle circulation rate S' is 30-70% of the maximum feed rate of the regenerating agent.

[0025] Optionally, the method further includes: preparing the catalytic cracking regeneration operation simulation evaluation system to a steady state; after the catalytic cracking regeneration operation simulation evaluation system reaches the steady state conditions, introducing the regenerator into the catalytic cracking regeneration operation simulation evaluation system and carrying out the regeneration simulation reaction; wherein the steady state conditions include: the bed stock in the regenerator reaching a steady state and the composition of pollutants in the regenerated flue gas reaching a steady state.

[0026] Optionally, the steady-state preparation includes the following steps: pre-setting a balancing agent in the regenerator, then introducing coking gas into the regenerator to fluidize the balancing agent; and heating the bed of the regenerator; when the bed temperature in the regenerator reaches 650-750°C, allowing the pre-regenerating agent to enter the regenerator through the pre-regenerating agent feeding unit, and allowing the balancing agent in the regenerator to flow out through the regenerator outlet at the bottom of the regenerator, displacing the balancing agent; optionally, the particles of the balancing agent... The average particle size is 60-90 μm, and the carbon content is 0.01-0.2% by weight; the average particle size of the pre-regenerating agent is 60-90 μm, and the carbon content is 0.5-3% by weight; optionally, during the replacement process, the introduction flow rate of the pre-regenerating agent is 80-120% of the particle circulation volume S' of the regenerating agent; the replacement time is 1.4-2 times the average residence time of particles in the industrial regenerator; preferably, the balancing agent replacement is completed when the pre-regenerating agent present in the bed is considered to be 80-90% by weight of the total particles in the bed.

[0027] Optionally, the regenerator has multiple sampling ports at different locations on its sidewall; the method further includes: during steady-state preparation, obtaining test pressure values ​​at fixed locations within the regenerator bed at different times through the multiple sampling ports of the regenerator; performing the following steps (a) to (c) on the pressure data obtained at each fixed location: (a) processing the test pressure values ​​using a moving average method to obtain the true pressure value; (b) fitting the true pressure value-time data at the fixed location to obtain a true pressure value-time fitting curve; (c) obtaining the slope 'a' value of the true pressure value-time fitting curve within the first operating cycle, and determining whether the bed stock at that location within the regenerator has reached a steady state based on the 'a' value; Optionally, when the 'a' value satisfies: -1≤a≤1, preferably -0.3≤a≤0.3, the bed stock within the regenerator has reached a steady state; Optionally, the time of the first operating cycle is less than 5s, preferably 0.5 to 2s;

[0028] Preferably, the slope a value is obtained by the following formula (5):

[0029]

[0030] N represents the number of pressure data points at a fixed location; p ti This represents the true pressure value at the i-th point at a fixed location, in Pa; t i Let represent the time corresponding to the i-th point, in seconds.

[0031] Optionally, after the bed stock in the regenerator reaches a steady state, the method further includes: continuing operation and continuously acquiring CO2 concentration data in the regenerated flue gas generated by regenerator 2-1 during operation; then, after each second operating cycle, calculating the concentration standard deviation σ based on the acquired CO2 concentration data. CO2 And according to σ CO2 Determine whether the composition of pollutants in the regenerated flue gas has reached a steady state; optionally, when σ CO2 The concentration is below 0.5%, preferably below 0.2%, and the composition of pollutants in the regenerated flue gas reaches a steady state; optionally, the second operating cycle is 1–20 s, preferably 1–5 s; preferably, the concentration standard deviation σ CO2 The number of CO2 concentration data required for calculation is 10 to 60, preferably 20 to 40; preferably, after the bed stock in the regenerator reaches a steady state, the system continues to run for 0 to 10 times the average residence time of the industrial unit, and then the CO2 concentration data in the regenerated flue gas are obtained.

[0032] Optionally, the method further includes: after the bed stock in the regenerator reaches a steady state, determining whether the first operating time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds an operating time threshold, wherein the first operating time is counted from the start of steady-state preparation; when the first operating time does not exceed the operating time threshold, the system continues to operate; when the first operating time exceeds the operating time threshold, the system stops operating; and when σ CO2 When the value is above 0.5%, it is determined whether the second operating time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds the operating time threshold, wherein the second operating time is calculated from the steady-state preparation start time; when the second operating time does not exceed the operating time threshold, the system continues to operate; when the second operating time exceeds the operating time threshold, the system stops operating; preferably, the operating time threshold is 10 to 40 times the average residence time of particles in the industrial regenerator; more preferably, it is 15 to 30 times.

[0033] Optionally, the simulation result data includes the concentrations of carbon dioxide and carbon monoxide in the regenerated flue gas; the step of determining whether the regeneration simulation reaction was successful based on the simulation result data includes: determining whether the composition of the flue gas products of the simulated regeneration reaction was successfully simulated based on the γ value obtained by the following formula (6):

[0034] γ=MAX[|c o2 -c′ o2 / c o2 |,|c co2 -c′ co2 / c co2 |,|c co -c′ co / c co |] Equation (6);

[0035] When γ < 5%, the simulation is successful; where c o2 c' represents the volume concentration of oxygen in the regenerated flue gas of an industrial plant, expressed as a percentage by volume. o2 c represents the volume concentration of oxygen in the regenerated flue gas in the catalytic cracking regeneration operation simulation evaluation system, expressed as a percentage by volume. co2 c' represents the volume concentration of carbon dioxide in the regenerated flue gas of an industrial plant, expressed as a percentage by volume. co2 The volume concentration of carbon dioxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation evaluation system is expressed as %; c co This indicates the volume concentration of carbon monoxide in the regenerated flue gas of an industrial plant, expressed as a percentage by volume (c'). co This represents the volume concentration of carbon monoxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation and evaluation system, expressed as a volume%.

[0036] Optionally, after successful simulation, a regeneration experiment of the regenerating agent is conducted, and regeneration result data is collected; the effect of the regeneration experiment is evaluated based on the regeneration result data; optionally, the regeneration result data includes the carbon burning intensity S. c The evaluation of the effect of the regeneration experiment based on the regeneration result data includes: obtaining the carbon burning intensity S of the regeneration experiment according to the following formula (7). c The value, and then based on the carbonization intensity S c The effectiveness of the regeneration experiment was evaluated, including S c A higher value indicates a better outcome in the regeneration experiment.

[0037]

[0038] Where Sc is in kg / (t·h); C0 represents the carbon content of the regenerator, wt%; C2 represents the carbon content of the regenerator obtained from the catalytic cracking regeneration operation simulation evaluation system, wt%; h represents the static height of the bed inside the regenerator, m; d represents the inner diameter of the dense phase section of the regenerator, m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 .

[0039] Optionally, the variable diameter spiral coil is formed by winding a through hollow tube in a conical spiral pattern; and along the axial direction of the regenerator housing, the winding diameter of the variable diameter spiral coil gradually increases from top to bottom to form an upright cone, or the winding diameter gradually decreases from top to bottom to form an inverted cone, or multiple variable diameter spiral coils are combined and installed, and the combination and installation methods include: the top end of the conical shape of one variable diameter spiral coil is connected to the top end of the conical shape of another variable diameter spiral coil, or the bottom end of the conical shape of one variable diameter spiral coil is connected. The conical bottom end of another variable-diameter spiral coil is connected; optionally, the inner diameter of the variable-diameter spiral coil is 3-8 mm, and the thread pitch of the center line of each coil layer is 3-15 mm; the wall thickness of the variable-diameter spiral coil is 0.75-2 mm; the maximum winding diameter of the variable-diameter spiral coil is 80-95% of the inner diameter of the regenerator shell, wherein the maximum winding diameter refers to the maximum diameter of the conical shape of the variable-diameter spiral coil; optionally, the hollow tube is a seamless steel tube; optionally, the shape of the hollow tube is a round tube or a square or rectangular tube.

[0040] Optionally, the regenerator shell is a constant-diameter cylinder or a variable-diameter cylinder; the cross-section of the regenerator shell is circular; preferably, the regenerator shell is a variable-diameter cylinder, which is composed of an upper cylindrical shell and a lower conical shell coaxially and sealed together; the heat exchange medium internal component is disposed inside the upper cylindrical shell of the regenerator and is coaxially disposed with the upper cylindrical shell; the regenerant outlet is located at the bottom of the lower conical shell, and the regenerant outlet is connected to the regenerant recovery unit; optionally, the inner diameter of the upper cylindrical shell is 30-100 mm; the height-to-diameter ratio is 1-50:1, preferably 4-30:1; the bottom cone angle of the lower conical shell is 60-150°, preferably 90-120°.

[0041] Optionally, the pre-treatment agent storage and feeding unit includes a pre-treatment agent silo, a feeding screw, an external pressure protective gas structure, and a pre-treatment riser; the feeding screw includes an idle section, a feeding section, and a conveying section; the external pressure protective gas structure includes an external pressure protective gas shell, a clamping end cap, and a pellet feeder shell, the external pressure protective gas shell being sleeved outside the idle section of the feeding screw, the clamping end cap being disposed at the end of the idle section, and the clamping end cap and the first end face of the external pressure protective gas shell being sealed by a protective gas shaft seal; a gap exists between the inner wall of the external pressure protective gas shell and the outer wall of the feeding screw to form an annular cavity around the feeding screw, and a through-hole is formed on the external pressure protective gas shell. The annular cavity is connected to an air source via the air inlet pipe and to the outside of the external pressure protective gas housing via the air outlet pipe. Optionally, the lateral length of the annular cavity is 0.5–8 mm. Optionally, a pressure sensor and a first control valve are provided on the protective gas inlet pipe. A back pressure valve is provided on the protective gas outlet pipe. The pellet feeder housing is sleeved outside the feeding section of the feeding screw, and the first end face of the pellet feeder housing and the second end face of the external pressure protective gas housing are sealed by a feeding shaft seal. The inlet end of the standpipe is connected to the conveying section of the feeding screw, and the outlet end extends into the housing of the regenerator.

[0042] Optionally, the length of the idle section of the feeding screw is 50-300 mm; the total length of the conveying section is 200-1000 mm. Preferably, a solid preheater is sleeved outside the conveying section of the feeding screw; preferably, the temperature of the regenerator after preheating by the solid preheater is 10-550°C, preferably 150-500°C; preferably, the feeding screw has an inclination angle from the idle section to the conveying section, preferably any inclination angle between -30° and 30°; the outlet end of the regenerator riser is located above the heat exchange medium internal component and is spaced apart from the top of the heat exchange medium internal component, and the inlet end of the regenerator riser is located below the static bed of the regenerator in the regenerator; optionally, the system further includes a heating furnace, which is located outside the regenerator; optionally, the number of heating furnaces is one or more.

[0043] Optionally, the system further includes a coking gas supply unit, which includes a pressure regulating valve, a gas flow meter, a gas preheater, and a gas distributor. The gas preheater has a gas preheating inlet and a gas preheating outlet. The gas preheating inlet is connected to a coking gas source. The pressure regulating valve and the gas flow meter are sequentially arranged along the gas flow direction on the gas source inlet pipeline of the gas preheating inlet. Preferably, the temperature of the coking gas after preheating by the gas preheater is 10–300°C, more preferably 100–250°C. The gas distributor has a coking gas inlet and a distribution port. The coking gas inlet is connected to the preheated gas outlet of the gas preheater. The gas distributor extends from the lower part of the regenerator housing into the regenerator, and the outlet of the distribution port of the gas distributor faces the bottom of the housing. Preferably, the gas distributor extends from the bottom of the upper cylindrical housing of the regenerator into the regenerator, and the outlet of the distribution port of the gas distributor faces the bottom of the lower conical housing of the regenerator.

[0044] Optionally, the system further includes an analysis unit; the analysis unit includes a flue gas sampling device and a tail gas analyzer; the regenerator further includes a flue gas filtration device, which is disposed in the upper part of the regenerator housing; the flue gas inlet of the tail gas analyzer is connected to the flue gas outlet of the flue gas filtration device.

[0045] The regenerator housing has a flue gas collection port on its side wall, which is connected to the flue gas sampling device. Preferably, multiple flue gas collection ports are provided at different heights along the axial direction of the regenerator housing side wall. Optionally, the system further includes a regenerator recovery unit, which includes a discharge valve, a discharge hopper, a discharge hopper inlet valve, a discharge hopper back pressure valve, a pressure sensor, and a discharge valve. The discharge hopper is provided with a regenerator inlet, a discharge outlet, a discharge hopper inlet, and a discharge hopper gas outlet. The regenerator inlet is connected to the regenerator outlet of the regenerator. The discharge hopper inlet is located at the top of the discharge hopper, and the discharge hopper inlet valve is provided on the pipeline connecting the discharge hopper inlet to the gas source. The discharge hopper gas outlet is located at the top of the discharge hopper and is connected to the external environment through an outlet pipeline. The discharge hopper back pressure valve is provided on the gas pipeline, and the pressure sensor is provided between the discharge hopper gas outlet and the discharge hopper back pressure valve.

[0046] Optionally, during the regeneration simulation reaction, the method includes: introducing the regenerator into the regenerator through the feed outlet of the regenerator feeding unit; introducing coking gas into the regenerator through the coking gas supply unit, and performing coking regeneration treatment on the regenerator in the regenerator to obtain regenerated flue gas and regenerator; introducing heat exchange medium into the variable diameter spiral coil tube through the heat exchange medium inlet of the heat exchange medium internal component, so that the heat exchange medium exchanges heat with the substances in the regenerator; allowing the regenerated flue gas to enter the analysis unit for analysis; and allowing the regenerator to enter the regenerator recovery unit for regenerator recovery treatment; preferably, the oxygen volume content in the coking gas is 0-100%, preferably 0.5-25%; the reaction conditions in the regenerator include: a temperature of 500-800℃, a pressure of 0.01-0.6MPa, preferably 0.2-0.5MPa; and a coking gas volume hourly space velocity of 6-50000h⁻¹. -1 Preferably 200-3000h -1 The residence time of the regenerator is 1 to 240 minutes, preferably 2 to 60 minutes; optionally, the feeding speed of the feeding screw in the regenerator feeding unit to the regenerator is 0.1 to 20 g / s, and the working pressure of the feeding screw in the regenerator feeding unit is 0 to 0.5 MPa.

[0047] Through the above technical solution, this disclosure provides a method for simulating the catalytic cracking regeneration process and evaluating its regeneration effect. This method employs a continuous catalytic cracking regeneration operation simulation and evaluation system, which can achieve continuous steady-state operation and is suitable for construction in small to medium-sized laboratories. It simulates a complete catalytic cracking regeneration process that more closely resembles actual industrial plants, and is easy to operate. This allows for more accurate and convenient evaluation of the coking effect of catalytic cracking regeneration under different regeneration conditions. Before conducting the simulation, the experimental operating parameters of the simulated catalytic cracking regeneration process are predetermined, which helps to more closely approximate the conditions of actual industrial plants.

[0048] Furthermore, this disclosure incorporates a variable-diameter spiral coil-shaped heat exchange medium internal component within the regenerator. On one hand, the spiral-shaped heat exchange medium internal component has a large heat exchange area. By introducing the heat exchange medium into the coil, excess heat from the regeneration and coking process can be removed, regulating the internal temperature of the regenerator and maintaining a stable temperature field. On the other hand, the variable-diameter spiral coil can also regulate the internal flow field of the regenerator, break up bubbles, prevent bubbles from coalescing into larger bubbles, avoid slugging problems caused by increased bed height within the regenerator, and maintain a stable flow field. Moreover, the variable-diameter coiling along the regenerator axis increases the vertical height of the internal component, and the multi-layered structure of the coil also increases the effective flow area.

[0049] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0050] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0051] Figure 1 This is an exemplary flowchart of a simulated catalytic cracking regeneration process and a method for evaluating regeneration effects provided in this disclosure.

[0052] Figure 2 This is an exemplary structural diagram of the continuous catalytic cracking regeneration operation simulation and evaluation system provided in this disclosure.

[0053] Figure 3 This is an exemplary structural diagram of the internal components of the heat exchange medium in the simulation evaluation system provided in this disclosure.

[0054] Figure 4 This is an exemplary structural diagram of the internal components of the heat exchange medium in the simulation evaluation system provided in this disclosure.

[0055] Figure 5 This is an exemplary structural diagram of the internal components of the heat exchange medium in the simulation evaluation system provided in this disclosure.

[0056] Figure 6 This is an exemplary structural diagram of the external pressure protective gas structure in the simulation evaluation system provided in this disclosure.

[0057] Figure 7 This is an exemplary structural diagram of a flue gas sampling tube in the simulation evaluation system provided in this disclosure.

[0058] Figure 8 This is an exemplary structural diagram of the continuous catalytic cracking regeneration operation simulation and evaluation system provided in this disclosure.

[0059] Figure 9 This is a graph of bed pressure-time data collected in Example 1.

[0060] Figure 10 This is a graph of bed pressure-time data collected in Example 1.

[0061] Figure 11 This is a graph showing the changes in CO2 and CO concentrations in the regenerated flue gas of Example 1 over reaction time.

[0062] Figure 12 This is a graph showing the changes in CO2 and CO concentrations in the regenerated flue gas over reaction time in Example 2.

[0063] Figure 13 The graph showing the changes in CO2 and CO concentrations in the regenerated flue gas of Comparative Example 1 over reaction time.

[0064] Explanation of reference numerals in the attached figures

[0065] 1-1. Preparing agent silo; 1-2. External pressure protective gas structure; 1-3. Solid preheater; 1-4. Feeding screw; 1-5. Preparing agent riser; 1-2-1. Pellet feeder housing; 1-2-2. Feeding shaft seal; 1-2-3. O-ring; 1-2-4. Bolt fasteners; 1-2-5. External pressure protective gas housing; 1-2-6. Air inlet pipe; 1-2-7. Compression end cap; 1-2-8. Protective gas shaft seal; 1-2-9. Air outlet pipe;

[0066] 2-1. Regenerator; 2-2. Heating furnace; 2-3. Flue gas filtration device; 2-4. Heat exchanger inlet valve; 2-5. Heat exchange medium internal components; 2-6. Gas distributor; 2-7. Heat exchanger outlet valve;

[0067] 3-1. Discharge valve; 3-2. Discharge hopper; 3-3. Discharge hopper air inlet valve; 3-4. Discharge hopper back pressure valve; 3-5. Pressure sensor; 3-6. Unloading valve;

[0068] 4-1. Pressure regulating valve; 4-2. Gas flow meter; 4-3. Gas preheater;

[0069] 5-1 Reactor back pressure valve; 5-2 Gas flow meter; 5-3 Three-way valve; 5-4 Exhaust gas analyzer; 5-5 Flue gas sampling equipment; 5-5-1 Flue gas sampling tube; 5-5-2 Temperature sensor; 5-5-3 Filter; 5-5-4 Pressure sensor; 5-5-5 Flue gas sampling valve; 5-5-6 Flue gas sampling bag Detailed Implementation

[0070] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0071] This disclosure provides a method for simulating a catalytic cracking regeneration process and evaluating the regeneration effect, the method comprising the following steps:

[0072] The experimental operating parameters for simulating the catalytic cracking regeneration process are determined, wherein the experimental operating parameters include: the apparent gas velocity of the coke gas, the standard inlet gas flow rate of the coke gas, the apparent pressure inside the regenerator, and the particle circulation rate of the regenerator regenerant.

[0073] The spent agent is introduced into a continuous catalytic cracking regeneration operation simulation and evaluation system, and a regeneration simulation reaction is carried out under the experimental operating parameters. Simulation result data is collected, and the success of the regeneration simulation reaction is determined based on the simulation result data.

[0074] The continuous catalytic cracking regeneration operation simulation and evaluation system includes a feed unit for the regenerator and a regenerator 2-1.

[0075] The regenerator 2-1 includes a shell, a regenerator inlet, a heat exchange medium internal component 2-5, a coking gas inlet, and a regenerator outlet; wherein the heat exchange medium internal component 2-5 is formed as a variable diameter spiral coil and is coiled around the axial direction of the regenerator 2-1 inside the shell;

[0076] The heat exchange medium internal component 2-5 includes a heat exchange medium inlet and a heat exchange medium outlet; the heat exchange medium inlet and the heat exchange medium outlet are respectively extended to the outside of the regenerator 2-1 shell through pipelines, so that the heat exchange medium inside the heat exchange medium internal component 2-5 exchanges heat with the material inside the regenerator 2-1 shell only through the pipe wall.

[0077] This disclosure provides a method for simulating the catalytic cracking regeneration process and evaluating its regeneration effect. This method employs a continuous catalytic cracking regeneration operation simulation and evaluation system, which can achieve continuous steady-state operation and is suitable for construction in small to medium-sized laboratories. It simulates a complete catalytic cracking regeneration process that more closely resembles actual industrial plants, and is easy to operate. This allows for more accurate and convenient evaluation of the coking effect of catalytic cracking regeneration under different regeneration conditions. Before conducting the simulation, the experimental operating parameters of the simulated catalytic cracking regeneration process are predetermined, which helps to more closely approximate the conditions of actual industrial plants.

[0078] Furthermore, this disclosure incorporates a variable-diameter spiral coil-shaped heat exchange medium internal component within the regenerator. On one hand, the spiral-shaped heat exchange medium internal component has a large heat exchange area. By introducing the heat exchange medium into the coil, excess heat from the regeneration and coking process can be removed, regulating the internal temperature of the regenerator and maintaining a stable temperature field. On the other hand, the variable-diameter spiral coil can also regulate the internal flow field of the regenerator, break up bubbles, prevent bubbles from coalescing into larger bubbles, avoid slugging problems caused by increased bed height within the regenerator, and maintain a stable flow field. Moreover, the variable-diameter coiling along the regenerator axis increases the vertical height of the internal component, and the multi-layered structure of the coil also increases the effective flow area.

[0079] In this disclosure, "variable diameter spiral coil" refers to a spiral coil with different coil diameters during the spiral winding process. For the specific structure of the simulation system, please refer to [link to simulation system]. Figure 2 The specific structure of the simulation system used will be described in detail in the following sections.

[0080] The simulation method provided in this disclosure differs fundamentally from the control methods of batch reactors. Using the method provided in this disclosure (determining experimental operating parameters and combining them with a continuous catalytic cracking regeneration operation simulation and evaluation system), the steady state of the simulated system can be obtained, and sampling and analysis can be performed within the steady-state time. The simulation method provided in this disclosure differs from that of pilot-scale reactors in that the purpose of the regenerator in a pilot-scale reactor is to burn off the coke accumulated on the regenerator during the reaction. Generally, the apparent gas velocity in the regeneration process is controlled to be the same as that in industrial regeneration. However, this operating method leads to a higher oxygen content in the regeneration process, and the reaction inside the regenerator differs from the actual process. Furthermore, the pilot-scale reactor has less control over the internal pressure of the regenerator during the regeneration process because the pressure affects the product distribution inside the riser reactor.

[0081] Through extensive experimentation, the inventors of this publication have developed a method for determining experimental operating parameters in a simulation device that more closely approximates the actual regeneration process in an industrial facility.

[0082] In this disclosure, "experimental operating parameters of the actual regeneration process of industrial equipment" include the following two situations:

[0083] In the first scenario, if it is necessary to evaluate the production agent from an industrial plant that has already been used, then the relevant industrial parameters involved in the method provided in this disclosure can be the actual industrial parameters of the corresponding production agent.

[0084] The second scenario involves evaluating a newly developed catalyst that has not been used in industrial applications or for which industrial regenerator property data is unavailable for other reasons. In this case, the catalyst needs to undergo carbonization treatment in a reaction apparatus (such as a fixed-bed or fixed-fluidized-bed reactor commonly used in the art), and then the corresponding physical property parameters (such as the carbon content of the regenerator) are measured. The specific carbonization treatment process is carried out according to preset industrial parameters. Furthermore, the parameters of the industrial apparatus involved in the method disclosed herein (such as the bed static height and apparent gas velocity of the industrial regenerator) can be determined based on the industrial apparatus parameters pre-designed according to the target usage of the newly developed catalyst.

[0085] The "industrial" parameters involved in this disclosure can come from either actual industrial installations or pre-designed industrial parameters.

[0086] In one embodiment, the apparent gas velocity u is within the numerical range represented by [u1, u2]; the method further includes determining u1 by the following equation (1-1) and determining u2 by the following equation (1-2):

[0087]

[0088]

[0089] In equations (1-1) and (1-2), h represents the static height of the bed in regenerator 2-1, m; U represents the apparent gas velocity of the coking gas in the industrial regenerator, m / s; H represents the static height of the bed in the industrial regenerator, m; u1 and u2 represent the apparent gas velocities of the coking gas required for the simulation experiment, m / s; u t The terminal velocity of the industrial coking gas is expressed in m / s. Wherein, the terminal velocity u... t These are conventional parameters in the field and can be calculated using conventional methods in the field, such as the method disclosed in Section 3, Chapter 1, Part 2 of the Fluidization Handbook.

[0090] This disclosure places the gas residence similarity coefficient k within a suitable range [k1, k2]. Then, based on the calculation relationships summarized by the inventors as shown in equations (1-1) and (1-2), the selection range of the apparent gas velocity u in the simulation experiment [u1, u2] is obtained according to the range of k [k1, k2]. In a preferred embodiment, k1 is selected from any value between 0.8 and 0.9, more preferably 0.85; k2 is selected from any value between 1.1 and 1.2, more preferably 1.15.

[0091] In one embodiment, the method further includes determining the standard intake volume in the experimental operating parameters using the following formula (2):

[0092]

[0093] Where Q represents the standard intake volume, m 3 / s; d represents the inner diameter of the dense phase section of regenerator 2-1, in meters; ρ s This indicates the bulk density of the regenerator in the regenerator, in kg / m³. 3 C c The carbon content of the pre-regenerating agent is expressed as wt%; r represents the volume concentration of oxygen in the flue gas from the industrial regeneration process, expressed as volume%; e represents the volume ratio of carbon monoxide to carbon dioxide in the industrial regeneration flue gas; f represents the hydrogen-to-carbon molar ratio on the pre-regenerating agent; t s C represents the average residence time of particles in an industrial regenerator, in seconds. CO2 This indicates the volume concentration of CO2 in the regenerated flue gas.

[0094] The standard intake volume obtained by using the above formula (2) provided in this disclosure is closer to the actual operating conditions of industrial equipment, thus improving the simulation evaluation effect.

[0095] In this disclosure, the hydrogen-carbon molar ratio on the pre-regenerating agent is determined by first measuring the mass concentrations of hydrogen and carbon on the pre-regenerating agent using an organic elemental analyzer, and then calculating the hydrogen-carbon molar ratio.

[0096] In this disclosure, the inner diameter d of the dense phase section of the regenerator can be adopted as the inner diameter of the cylinder of the regenerator 2-1 in the simulation evaluation system.

[0097] In this disclosure, t s It can generally be obtained directly from an industrial regenerator, or it can be calculated using the following formula (2-1):

[0098]

[0099] In equation (2-1), V represents the amount of catalyst stored in the industrial regenerator, kg; and S represents the amount of industrial catalyst circulating, kg / s.

[0100] After determining the range of apparent gas velocity u and the standard intake volume Q, the range of apparent pressure inside the regenerator is further determined by combining u and Q.

[0101] In one embodiment, the method further includes determining the apparent pressure within the regenerator as experimental operating parameters using the following formula (3):

[0102]

[0103] Where p represents the required apparent pressure within the regenerator, in MPa; T represents the bed temperature inside the industrial regenerator, in °C; d represents the inner diameter of the dense phase section within regenerator 2-1, in meters; u represents the apparent gas velocity of the coking gas in the simulation experiment, in m / s; and Q represents the standard inlet flow rate of the coking gas, in cubic meters per second. 3 / s. Preferably, Q is calculated according to equation (2).

[0104] In this disclosure, since the apparent gas velocity u is within the numerical range represented by [u1, u2], the range value of the apparent pressure p [p1, p2] is also calculated accordingly.

[0105] In a preferred embodiment, the apparent pressure p within the regenerator in the experimental operating parameters is within the range of values ​​represented by [p1, p2].

[0106] The method also includes determining the apparent pressure p1 using the following equation (3-1) and determining the apparent pressure p2 using the following equation (3-2):

[0107]

[0108]

[0109] The meanings of each letter are the same as in equation (3); the methods for obtaining the apparent air velocities u1 and u2 are shown in equations (1-1) and (1-2).

[0110] According to this disclosure, for evaluation devices with a fixed bed height h, it is also necessary to further obtain the particle circulation rate S' in the experiment, g / s.

[0111] In one embodiment, the method further includes determining the particle circulation amount of the regenerant in the experimental operating parameters by means of the following formula (4):

[0112]

[0113] Where S' represents the required particle circulation rate of the regenerant, g / s; h represents the static bed height of regenerator 2-1, m; d represents the inner diameter of the dense phase section of regenerator 2-1, m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³.3 ;t s This represents the average residence time of particles in an industrial regenerator, expressed in seconds.

[0114] Optionally, the particle circulation rate S' is 30-70% of the maximum feeding rate of the feed agent.

[0115] In this disclosure, the pressure difference between the regenerator and the discharge hopper in the system is used for discharge. In order to ensure the stability of the amount stored in the regenerator, it is also necessary to maintain the pressure difference between the regenerator and the discharge hopper. For a fixed volume container, the simulated operation particle circulation volume has been determined by the method provided above (e.g., equation (4)). At this time, for steady-state operation, the flow rate at the back pressure valve of the discharge hopper can be set to a fixed value. The back pressure valve set flow rate ΔQ2, ml / min, is the volumetric flow rate of solid particles flowing in, which is directly calculated by the following equation (4-1):

[0116]

[0117] S” represents the mass flow rate of the regenerated agent in the evaluation experiment, in g / s; for a simple FCC regeneration and coking process, the particle size difference between the recycled agent and the oxidized agent is small, and S” can be calculated by the following formula (4-2):

[0118]

[0119] ρ2 represents the bulk density of the regenerant in regenerator 2-1 of the evaluation experiment, in kg / m³. 3 ;ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 ρ2 and ρs were measured using a mercury porosimeter. Equation (4-1) can then be transformed into equation (4-3):

[0120]

[0121] In this disclosure, after determining the experimental operating parameters, the experiment can begin, starting with the device start-up operation. The start-up process in this disclosure employs a displacement method, where a low-carbon balancing agent is pre-laid in the regenerator, followed by fluidization and heating. Once the bed temperature reaches the reaction temperature, the pre-laid balancing agent is gradually displaced from the bed using the regenerator to be evaluated.

[0122] In one embodiment, the method further includes: performing steady-state preparation on the catalytic cracking regeneration operation simulation evaluation system;

[0123] Once the catalytic cracking regeneration operation simulation evaluation system reaches steady-state conditions, the regenerator is introduced into the catalytic cracking regeneration operation simulation evaluation system to carry out the regeneration simulation reaction; wherein the steady-state conditions include the bed stock content in the regenerator 2-1 reaching a steady state and the composition of pollutants in the regenerated flue gas reaching a steady state.

[0124] In one specific embodiment, the steady-state preparation includes the following steps:

[0125] A balancing agent is pre-set in the regenerator 2-1, and then coking gas is introduced into the regenerator 2-1 to fluidize the balancing agent; and the bed of the regenerator 2-1 is heated to a higher temperature.

[0126] When the bed temperature inside the regenerator 2-1 reaches 650-750°C, the regenerating agent is introduced into the regenerator 2-1 through the regenerating agent feeding unit, and the balancing agent in the regenerator 2-1 flows out through the regenerating agent outlet at the bottom of the regenerator 2-1, replacing the balancing agent.

[0127] Optionally, the balancing agent has an average particle size of 60-90 μm and a carbon content of 0.01-0.2% by weight; the pre-generation agent has an average particle size of 60-90 μm and a carbon content of 0.5-3% by weight.

[0128] Optionally, during the replacement process, the flow rate of the regenerating agent is 80-120% of the particle circulation volume S' of the regenerating agent; the replacement time is 1.4-2 times the average residence time of particles in the regenerator.

[0129] Preferably, at the end of the balancing agent replacement, the amount of the residual agent present in the bed is 80-90% by weight of the total number of particles in the bed.

[0130] The inventors of this disclosure discovered, in experiments on particle residence time distribution characteristics conducted on a small-scale laboratory-grade device with a stable feed-discharge fluidized bed system, that under low solids circulation rates (average residence time > 3 min), the displacement within the bed is only related to the mass of particles injected into the bed, and is independent of the circulation rate. Therefore, a large particle circulation rate can be used to achieve rapid displacement operations, saving operation time. The displacement operation of this disclosure uses a large dose of at least 80% by weight of the particle circulation rate in rapid displacement experiments. Results show that the complete displacement time is generally 1.4 to 2 times the average residence time, influenced by the device structure; here, 85% by weight of the newly injected agent in the bed is used as the marker for complete displacement. Faster replacement of the low-carbon-content balancing agent in the bed with the high-carbon-content pre-renewal agent helps the internal reaction of the device reach steady state more quickly.

[0131] In this disclosure, the collected bed pressure data and flue gas data are used to calculate the corresponding parameters to determine whether the bed has reached a steady state of fluidization and reaction, and to carry out subsequent analysis and adjustment.

[0132] In this disclosure, pressure data is measured by pressure sensors installed in the regenerator. First, the pressure data obtained from the pressure sensors is processed using a moving average method to obtain the true pressure value after eliminating interference. The moving average method used for data processing is a conventional processing method known in the art, for example, the processing method described in the literature "Basic Principles and Applications of the Moving Average Method". Then, the pressure true value-time data is processed using the least squares method to obtain corresponding parameters (e.g., the slope of the fitted curve), which determine the current material state within the regenerator and can also predict future changes in material level.

[0133] The inventors of this disclosure have discovered that: in small-scale equipment, the pressure at a certain point inside the fluidized bed changes with time in a manner that is essentially consistent with the change in material level; when the bed stockpile in the regenerator remains constant, although the pressure at a fixed position inside the bed will fluctuate due to the influence of bubble and particle vibration, its true pressure value is also dynamically stable, which is the same as the situation in actual industrial equipment. For containers of equal diameter, within the operating range of this open circuit, when the bed stockpile increases steadily, its bed height also increases steadily. At this time, the true pressure value at a fixed point inside the bed, like the bed height, can be approximated as a linear function positively correlated with time. This characteristic can be used to calculate the secondary pressure-time function based on the signal transmitted by the pressure sensor, thereby judging and predicting the internal state of the fluidized bed. The secondary pressure-time function at a fixed position inside the bed is obtained according to the following equations (5), (5-1), and (5-2):

[0134] p t =at + b (5-1);

[0135]

[0136]

[0137] N represents the number of pressure data points at that fixed location; p ti This represents the true pressure value at the i-th point of the fixed position, in Pa; t i Let represent the time corresponding to the i-th point, in seconds.

[0138] In this disclosure, multiple pressure-time data points at a fixed point within the bed can be obtained using pressure sensors within the regenerator. By fitting these discrete pressure-time data points at that fixed point, a secondary pressure-time function for that fixed point can be obtained, where 'a' represents the slope of the fitted curve. If multiple pressure sensors are installed at fixed locations within the bed, the above calculation operation is performed for each fixed location.

[0139] In one specific embodiment, the regenerator 2-1 has multiple sampling ports at different locations on its side wall;

[0140] The method also includes: during the steady-state preparation process, obtaining the test pressure values ​​at different times at fixed positions within the regenerator bed 2-1 layer through multiple sampling ports of the regenerator 2-1;

[0141] The pressure data obtained at each fixed location are subjected to the following steps (a) to (c):

[0142] (a) The test pressure value is processed using the moving average method to obtain the true pressure value;

[0143] (b) Then, the true pressure-time data at the fixed location is fitted to obtain the true pressure-time fitting curve;

[0144] (c) During the first operating cycle, obtain the slope value 'a' of the pressure true value-time fitting curve, and determine the bed stock status at that location in the regenerator based on the value 'a'.

[0145] Optionally, the time of the first running cycle is less than 5 seconds, preferably 0.5 to 2 seconds. The smaller the time interval, the higher the accuracy.

[0146] Optionally, when the preset calculation cycle is run continuously, the value of a satisfies: -1≤a≤1, preferably -0.3≤a≤0.3, the bed stock in the regenerator reaches a steady state, and the time of the calculation cycle is not less than the time of the first running cycle.

[0147] In one specific embodiment, the preset calculation period is 10 to 30 seconds.

[0148] In this disclosure, when the calculated |a|≤1, it is considered that the bed stockpile is stable and the bed height remains unchanged; when a>1, the bed stockpile is gradually increasing and the bed height is also increasing; when a>-1, the bed stockpile and bed height are decreasing; under a fixed operating condition, the a value is also fixed under normal operating conditions. If the a value suddenly changes and exceeds the range of [-1,1], it indicates problems such as poor feeding or material blockage, and the cause should be investigated in time; if the pressure continues to increase or decrease, the material level should also be calculated in time. When the a value is greater than 1, it indicates that the discharge level is rising, and the discharge valve opening should be increased; when the a value is less than -1, it indicates that the stockpile is decreasing, and the discharge valve opening should be decreased. Through the above operation of adjusting the discharge valve opening, it is continuously adjusted until the a value is between [-1,1], preferably between [-0.3,0.3].

[0149] In a further embodiment, pressure sensors are installed at different fixed locations within the bed of regenerator 2-1, which can detect the pressure at multiple locations, making the determination of the bed stock level more accurate. When there are multiple fixed locations, the above calculation and judgment are performed for each fixed location. When the 'a' value of all fixed locations satisfies -1≤a≤1, preferably -0.3≤a≤0.3, the bed stock level in regenerator 2-1 is in a steady state.

[0150] In a further embodiment, if the influence of the discharge valve opening and bed differential pressure on the target catalyst discharge rate is uncertain at the initial stage of the experiment, steady-state discharge rate calibration must be performed first. Specifically, this includes: first, stopping the feeding and discharging, starting to heat up, and when the temperature of each part reaches the simulated required temperature, introducing nitrogen gas of the same apparent volume as in the simulated process into the regenerator 2-1 containing the specially selected balancing agent, adjusting the back pressure valve to make the pressure the same as the pressure in the regenerator 2-1 during the simulated process, and recording the true value p' of the pressure sensor in the dense phase bed at this time. Next, introducing pressurized gas into the discharge hopper to make its pressure the same as the pressure value obtained from the pressure sensor at the bottom of the regenerator 2-1. Turning on the feeder and setting it to the required feeding rate for the experiment. Opening the discharge valve according to the known characteristics of the balancing agent loaded in the regenerator before the experiment. Then opening the discharge hopper's gas outlet valve, setting the gas output to the previously calculated theoretical outflow rate. At this time, adjusting the discharge valve opening according to the value of the pressure-time function 'a', using the same adjustment method as described above. Continuously adjust until the value of 'a' is between [-1, 1], preferably between [-0.3, 0.3]. Record the opening degree β of the discharge valve at this point. Increase the opening degree of the discharge valve appropriately, and when the pressure value of the pressure sensor in the dense phase bed of regenerator 2-1 reaches p', adjust the opening degree of the discharge valve back to β. At this point, the bed stockpile is stable, and the next step of the experiment can begin.

[0151] In a further embodiment, such as Figure 1 As shown, once the bed density in the regenerator reaches a steady state, the method further includes:

[0152] Continue operation, continuously acquiring CO2 concentration data in the regenerated flue gas generated by regenerator 2-1 during operation; then, after each second operating cycle, calculate the concentration standard deviation σ based on the acquired CO2 concentration data. CO2 And according to σ CO2 Determine whether the composition of pollutants in the regenerated flue gas has reached a steady state; optionally, when σ CO2 The concentration is below 0.5%, preferably below 0.2%, so that the composition of pollutants in the regenerated flue gas reaches a steady state. Furthermore, when σ... CO2 If the concentration is below 0.5% and the CO2 concentration-time graph does not show a significant upward or downward trend, then the displacement is considered complete and the reaction has reached steady state.

[0153] In one specific embodiment, the CO2 concentration data acquisition time interval for continuously acquiring CO2 concentration data in the regenerated flue gas during operation is 0.5 to 20 seconds, preferably 1 to 10 seconds;

[0154] Preferably, the concentration standard deviation σ CO2 The number of CO2 concentration data points required for the calculation is 10 to 60, preferably 20 to 40.

[0155] Preferably, the second operating cycle is 1 to 20 seconds, more preferably 1 to 5 seconds;

[0156] Preferably, after the bed stock in regenerator 2-1 reaches a steady state, it continues to run for 0 to 10 times the average residence time of the industrial unit, and then the CO2 concentration data in the regenerated flue gas is obtained.

[0157] The method for obtaining flue gas data is as follows: the composition of flue gas pollutants is obtained by using the results of the flue gas analyzer connected to the regenerator outlet and mass chromatography to analyze the gas sampling bag samples collected during the steady-state experiment.

[0158] Where, σ CO2 The calculation method is shown in equation (8) below:

[0159]

[0160] Where n represents the number of CO2 concentration data used in the criterion calculation; c' co2,j This indicates the volume concentration of carbon dioxide in the regenerated flue gas of the evaluation device, expressed as volume%, 1≤j≤n; This represents the average volumetric carbon dioxide concentration of n flue gas gases within the calculation range of the criterion, expressed as a percentage of volume.

[0161] In a preferred embodiment, the method further includes:

[0162] After the bed stock in regenerator 2-1 reaches a steady state, it is determined whether the first operating time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds the operating time threshold, wherein the first operating time is calculated from the start of steady state preparation.

[0163] If the first running time does not exceed the running time threshold, the system continues to run;

[0164] The system stops running when the first running time exceeds the running time threshold; and

[0165] When σ CO2 When the value is above 0.5%, it is determined whether the second running time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds the running time threshold, wherein the second running time is calculated from the steady-state preparation start time.

[0166] If the second running time does not exceed the running time threshold, the system continues to run.

[0167] The system stops running when the second running time exceeds the running time threshold.

[0168] In this disclosure, at the start of the steady-state preparation process, an internal system timer (which can be set and controlled by a computer program) is initiated. The reaction characteristic number σ is calculated over a certain period (the second operating cycle). CO2 Determine whether the reaction in the reactor has reached a steady state. When σ CO2 If the concentration is above 0.5%, the system is considered not to have reached steady state, and it is determined whether the reaction time has exceeded the limit. If the time has exceeded the limit, the reaction is stopped, the simulation constant and experimental operating parameters are recalculated, the equipment is inspected, materials are loaded, and the experiment is repeated. If the time has not exceeded the limit, the system continues to operate.

[0169] In a preferred embodiment, the operating time threshold is 10 to 40 times the average residence time of particles in an industrial regenerator; preferably 15 to 30 times. This disclosure controls the reaction time to not exceed the operating time threshold, ensuring a stable reaction while allowing for a sufficient operating window, and preventing excessive consumption of regenerator materials.

[0170] When the bed stock level in the regenerator is at a steady state and the composition of pollutants in the regenerated flue gas also reaches a steady state, it indicates that the continuous catalytic cracking regeneration operation simulation evaluation system has reached a steady state, and the next step of the reactive regeneration simulation experiment can be carried out, including: introducing the reactive agent into the continuous catalytic cracking regeneration operation simulation evaluation system, conducting a regeneration simulation reaction under the experimental operating parameters, and collecting simulation result data; judging whether the catalytic cracking regeneration operation simulation evaluation system has successfully simulated based on the simulation result data.

[0171] In this disclosure, the composition of flue gas products is used as an important indicator to determine whether the simulation is successful.

[0172] In one specific embodiment, the simulation results data include the concentrations of carbon dioxide and carbon monoxide in the regenerated flue gas;

[0173] The method of determining whether the regeneration simulation reaction was successfully simulated based on the simulation result data includes:

[0174] The success of the simulation of the flue gas product composition of the regeneration reaction is determined by the γ value obtained from the following formula (6):

[0175] γ=MAX[|c o2 -c′ o2 / c o2 |,|c co2 -c′ co2 / c co2 |,|c co-c′ co / c co |] Equation (6);

[0176] When γ < 5%, it indicates that the simulation was successful and the effect was good, and data collection and evaluation can begin.

[0177] Among them, c o2 This indicates the volume concentration of oxygen in the regenerated flue gas of an industrial plant, expressed as a percentage by volume.

[0178] c' o2 c represents the volume concentration of oxygen in the regenerated flue gas in the catalytic cracking regeneration operation simulation evaluation system, expressed as a percentage by volume. co2 c' represents the volume concentration of carbon dioxide in the regenerated flue gas of an industrial plant, expressed as a percentage by volume. co2 The volume concentration of carbon dioxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation evaluation system is expressed as %; c co This indicates the volume concentration of carbon monoxide in the regenerated flue gas of an industrial plant, expressed as a percentage by volume (c'). co This represents the volume concentration of carbon monoxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation and evaluation system, expressed as a volume%.

[0179] In this disclosure, MAX[a,b,c] represents the maximum value among a, b, and c.

[0180] In a further embodiment, when γ is between 5% and 15%, it indicates that the simulation is successful. Generally, data acquisition and evaluation can be started according to the actual situation, or the device parameters such as device pressure, solid circulation volume, and gas flow rate can be slightly adjusted to try to reduce the γ value to below 5%. When γ is greater than 15%, it indicates that the simulation is unsuccessful, and the operating parameters should be recalculated or the device should be checked to reduce γ to below 5%.

[0181] After successful system simulation, the regeneration coke burning effect can be evaluated using data obtained from the system regeneration process. The representative performance indicator of coke burning effect is coke burning intensity, which is obtained by analyzing the carbon content of the catalyst before and after regeneration using a carbon-sulfur analyzer and an organic elemental analyzer.

[0182] In one specific embodiment, the method further includes: after a successful simulation, conducting a regeneration experiment of the regenerating agent and collecting regeneration result data; and evaluating the effect of the regeneration experiment based on the regeneration result data.

[0183] Optionally, the regeneration result data includes char intensity S. c The evaluation of the regeneration experiment's effectiveness based on the regeneration result data includes:

[0184] The carbonization intensity S of the regeneration experiment is obtained according to the following formula (7). c The value, and then based on the carbonization intensity Sc The effectiveness of the regeneration experiment was evaluated, including S c A higher value indicates a better outcome in the regeneration experiment.

[0185]

[0186] Where Sc is in kg / (t·h); C0 represents the carbon content of the regenerator, wt%; C2 represents the carbon content of the regenerator obtained from the catalytic cracking regeneration operation simulation evaluation system, wt%; h represents the static height of the bed in regenerator 2-1, m; d represents the inner diameter of the dense phase section of regenerator 2-1, m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 .

[0187] Specifically, for the simulation evaluation of single-stage regeneration process, when Sc is less than 60, the coking effect is poor; when Sc is between 60 and 85, it is average; when Sc is between 85 and 100, it is good; and when Sc is greater than 100, it is excellent.

[0188] In one implementation, the temperature field inside the bed can also be fitted using data from various temperature sensors.

[0189] In one specific embodiment, the calculation of various parameters in this disclosure can be performed automatically using conventional software or programs, for example, by inputting industrial device parameters, inputting simulation constants, and then having the program automatically calculate the experimental parameters.

[0190] In one specific embodiment, the method further includes an experimental preparation step, including: screening, conditioning, heating, drying, aging, and contamination of the regenerating agent to be regenerated; introducing the gas required for the reaction (coke gas) according to the simulation experiment; starting the device; and pre-laying the balancing agent in the regenerator.

[0191] The structure of the continuous catalytic cracking regeneration operation simulation and evaluation system used in this disclosure is described below.

[0192] In one specific implementation, such as Figure 1 As shown, the simulated catalytic cracking regeneration process and the method for evaluating the regeneration effect include the following steps:

[0193] First, experimental preparation steps are performed, including: screening, conditioning, heating, drying, aging, and contamination of the reactant. The coking gas is calculated and adjusted according to the evaluation requirements. Then, the required industrial parameters and simulation constants (k1 and k2) are calculated by sequentially inputting the experimental operation parameter formulas, determining the various experimental operation parameters required in the simulation experiment. After processing, steady-state experiment preparation is carried out. A specially selected balancing agent is added to the regenerator. All instruments are turned on, and the corresponding heaters are activated to heat the balancing agent, coking gas, and regenerator to the preset temperature. Gas intake begins; the coking oxidizing gas enters from the coking gas supply unit, passes through the pressure regulating valve and gas preheater, and is evenly distributed to the bottom of the regenerator by the gas distributor, flowing upwards. The gas flow and internal pressure of the regenerator are adjusted to appropriate values ​​by adjusting the inlet gas flow and the back pressure valve at the regenerator filter outlet. The feeder is turned on, and the regenerator is added to the regenerator to react with the coking gas. During the feeding process, the pressure of the inlet pipe and back pressure valve in the discharge hopper is adjusted to match that of the regenerator. The discharge valve is opened, and the opening degree of the discharge valve and the pressure in the discharge hopper are adjusted. The deviation between the preset feeding rate and the actual feeding rate and the actual discharge rate can be calibrated based on the changes in the pressure sensor values ​​on the side wall of the regenerator. The flow rate of the heat exchange medium in the annular heat exchanger is controlled by the valve to remove excess heat from the regenerator and keep the temperature constant. The regenerator enters the discharge hopper through the discharge pipe. The flue gas flows out from the filter at the top of the regenerator and is analyzed by the flue gas analyzer. During this period, the gas velocity, feeding rate, and heat exchanger medium flow rate are adjusted according to the instruments. After feeding for a period of time, when the flue gas analyzer shows stable composition and stable internal reaction temperature, it indicates that the catalyst originally laid in the regenerator has been completely replaced, and the bed fluidization and reaction state in the regenerator are stable, and steady-state experiments can begin.

[0194] Gas sampling and analysis, along with monitoring of parameters such as temperature and pressure, were performed using sampling tubes, a flue gas analyzer, temperature sensors, and pressure sensors. After the experiment, catalyst particles were collected from the top of the feed silo and the discharge silo. Carbon-sulfur analyzers and organic elemental analyzers were used to analyze the carbon content of the catalyst before and after regeneration, determining the amount of carbon burned during the regeneration operation and assessing the regeneration carbon burning effect. A flue gas analyzer connected to the regenerator outlet was used to analyze the components of interest in the regenerated flue gas, including carbon dioxide, carbon monoxide, nitrogen oxides, and sulfur oxides. Gas samples collected during the experiment were sent to a mass spectrometer for steady-state analysis to obtain changes in gas composition during the reaction process. The amplitude and frequency of pressure fluctuations within the bed were calculated using pressure data obtained from the bed pressure monitoring points. The temperature field within the bed was fitted using data from various temperature sensors. Based on these data, the regeneration effect of the simulated catalytic cracking regeneration operation was evaluated.

[0195] The calculation methods for experimental operating parameters of the simulated catalytic cracking regeneration process, the methods and standards for judging the steady state, and the methods and standards for evaluating the effect have all been described in detail above and will not be repeated here.

[0196] In a further embodiment, such as Figure 1 As shown, when the simulation target is changed, such as different regeneration processes of the recycled agent or different industrial regenerator structures, it is necessary to recalculate the operating parameters according to the actual size of the device, and then re-perform steady-state preparation, simulated reaction, and effect evaluation. This disclosure allows for the simple confirmation of consistent experimental operating parameters for different simulation targets, and enables effective simulation evaluation of different simulation targets using the same continuous catalytic cracking regeneration operation simulation evaluation system, which is simple and easy to implement.

[0197] The specific structure of the continuous catalytic cracking regeneration operation simulation and evaluation system used in this disclosure is described below.

[0198] In one embodiment, the variable diameter spiral coil is formed by winding a through hollow tube in a conical spiral line; and along the axial direction of the regenerator 2-1 shell, the winding diameter of the variable diameter spiral coil gradually increases from top to bottom to form an upright cone, or the winding diameter gradually decreases from top to bottom to form an inverted cone.

[0199] In this disclosure, "an upright cone" means that the apex of the cone is at the top and the base is at the bottom; "an inverted cone" means that the apex of the cone is at the bottom and the base is at the top.

[0200] In one specific implementation, Figure 3 and Figure 4 The diagram illustrates a schematic of a variable-diameter spiral coil, where the coil can be viewed as a hollow tube spirally wound from top to bottom with a gradually decreasing diameter along the central axis, resulting in an "inverted cone" shape; in further embodiments, such as... Figure 3 As shown, the opening directions of the two nozzles of the spiral coil are set at 180° in the horizontal direction to balance the uneven flow field distribution caused by the asymmetry of the helix. Furthermore, the coiling method of the "upright cone" is the opposite of that of the "inverted cone," which will not be described in detail here.

[0201] In this disclosure, during the fluidization process, the gas-solid two-phase flow passes through a variable-diameter spiral coil. The large bubble can be regarded as a tiny cylinder flowing around each differential section perpendicular to the coil axis. The wake formed by the cylindrical flow around each differential section is itself non-ideal axisymmetric, and the flow direction of the wake at different interfaces is also different. The vortices formed in the wake interfere with each other, enhance gas disturbance, break the bubble, and the shape of the upper part being larger than the lower part makes it easier for the upward-moving two-phase fluid at the bottom to rise from the side wall. The middle part consists more of downward-moving particles. The downward-moving particles come into contact with and mix with the wake of the surrounding gas, further enhancing the mass and heat transfer effect.

[0202] In a further embodiment, one or more heat exchange medium internal components can be installed within the regenerator 2-1, preferably an even number depending on the internal space of the regenerator. Specifically, during installation, components with the same coil diameter are connected together to form one unit, that is, multiple variable diameter spiral coils are assembled and installed in combination. The assembly methods include: connecting the conical top of one variable diameter spiral coil to the conical top of another variable diameter spiral coil, or connecting the conical bottom of one variable diameter spiral coil to the conical bottom of another variable diameter spiral coil. One specific embodiment is as follows... Figure 5 As shown, preferably, multiple heat exchange media (multiple variable diameter spiral coils) are connected into one piece in the axial direction of the regenerator 2-1. The internal components of the multiple heat exchange media use the same heat exchange media inlet and heat exchange media outlet as a whole. Therefore, the multiple heat exchange media internal components can also be regarded as being wound around the same central axis via the same coil.

[0203] Specifically, the following illustration uses the arrangement of two heat exchange medium internal components as an example: Figure 5 As shown, the coil diameter gradually decreases and then gradually increases from top to bottom, so the upper and lower variable-diameter spiral sections share a minimum coil diameter (considered as two cones arranged "cone angle to cone angle"); or the coil diameter can gradually increase and then gradually decrease from bottom to top, so the upper and lower variable-diameter spiral sections share a maximum coil diameter (considered as two cones arranged "base side to base side"); when two heat exchange medium internal components 2-5 arranged vertically are set in the regenerator 2-1 using the above method, the heat exchange medium follows the "bottom in, top out" principle, and the heat exchange medium inlet flow direction of the lower heat exchange medium internal component is arranged 180° opposite to the heat exchange medium outlet flow direction of the upper heat exchange medium internal component. Furthermore, when multiple heat exchange medium internal components need to be arranged, the coil can continue to be coiled in a conical spiral manner. Taking four heat exchange medium internal components as an example, in the upward direction, the connection methods between adjacent internal components include the following two methods:

[0204] Method 1: Cone angle to cone angle (1st and 2nd inner components) - bottom edge to bottom edge (2nd and 3rd inner components) - cone angle to cone angle (3rd and 4th inner components). In this method, the diameter of the bottommost 1st inner component gradually decreases from bottom to top.

[0205] Method 2: Bottom edge to bottom edge (1st and 2nd inner components) - Cone angle to cone angle (2nd and 3rd inner components) - Bottom edge to bottom edge (3rd and 4th inner components). In this method, the diameter of the bottommost 1st inner component gradually increases from bottom to top.

[0206] In this disclosure, the mass and heat transfer effect can be further improved by setting multiple heat exchange medium internal components.

[0207] In one specific embodiment, optionally, the inner diameter of the variable diameter spiral coil is 3-8 mm, the thread pitch of the center line of each layer of coil is 3-15 mm, preferably 5-10 mm; and the wall thickness of the variable diameter spiral coil is 0.75-2 mm.

[0208] The maximum winding diameter of the variable diameter threaded coil obtained from its outer diameter is 80-95% of the inner diameter of the regenerator 2-1 shell, preferably 85-92%; wherein the maximum winding diameter refers to the maximum diameter of the conical shape of the variable diameter threaded coil. In this disclosure, the maximum diameter is calculated according to the distance between the outermost tube walls of the coil. Setting the heat exchange medium internal components according to the ratio between the maximum winding diameter and the inner diameter of the regenerator 2-1 shell provided in this disclosure can better improve the heat and mass transfer effect and maintain steady-state operation inside the regenerator.

[0209] Optionally, the hollow tube is a seamless steel pipe; optionally, the hollow tube is round or rectangular, or other hollow tubes of other materials and shapes known in the art can also be used.

[0210] In one embodiment, the shell of the regenerator 2-1 is a constant-diameter cylinder or a variable-diameter cylinder, and the cross-section of the shell of the regenerator 2-1 is circular. In a preferred embodiment, such as... Figure 2 As shown, the shell of regenerator 2-1 is a variable-diameter cylinder, which consists of an upper cylindrical shell and a lower conical shell connected coaxially and sealed. The heat exchange medium internal component 2-5 is disposed within the upper cylindrical shell of regenerator 2-1 and is coaxially arranged with the upper cylindrical shell. The regenerant outlet is located at the bottom of the lower conical shell and is connected to the regenerant recovery unit. The variable-diameter cylinder preferred in this disclosure allows the sidewall of the lower conical shell to reflect the gas at the bottom of the cone when coking gas is introduced, which is beneficial for fluidizing the solid particles within the regenerator.

[0211] In one specific embodiment, the inner diameter of the upper cylindrical shell is 30-100 mm; the height-to-diameter ratio is 1-50:1, preferably 4-30:1; the height-to-diameter ratio refers to the ratio of the height of the upper cylindrical shell to the inner diameter of the upper cylindrical shell.

[0212] The bottom cone angle of the lower conical shell is 60-150°, preferably 90-120°.

[0213] The regenerator 2-1 in this disclosure also includes a feed pipe and a discharge pipe. The feed pipe is located at the top of the bed in the regenerator 2-1, and the discharge pipe is located at the bottom of the regenerator 2-1. The inner diameters of the feed pipe and the discharge pipe of the regenerator 2-1 are 4 to 30 mm, preferably 6 to 10 mm.

[0214] This disclosure describes a discharge pipe with a discharge valve connected to the bottom of the regenerator cone. During steady-state preparation, simulation experiments, and evaluation experiments, the discharge speed and the bed stock and bed height inside the regenerator can be adjusted by controlling the opening of the discharge valve. After the evaluation is completed, the material is discharged as a discharge outlet.

[0215] In one implementation, such as Figure 2 and Figure 6 As shown, the pre-generation agent storage and feeding unit includes a pre-generation agent silo 1-1, a feeding screw 1-4, an external pressure protective gas structure 1-2, and a pre-generation agent riser 1-5;

[0216] The feeding screws 1-4 are divided into a feeding section and a conveying section along the material flow direction. Preferably, the feeding screw also includes an empty section set upstream of the feeding section, that is, an empty screw area is set between the feeding port of the feeding screw and the motor end of the screw, instead of feeding directly at the motor end of the screw.

[0217] The external pressure protective gas structure 1-2 includes an external pressure protective gas housing 1-2-5, a pressing end cap 1-2-7, and a pellet feeder housing 1-2-1. The external pressure protective gas housing 1-2-5 is sleeved outside the empty section of the feeding screw 1-4, and the pressing end cap 1-2-7 is located at the end of the empty section. The pressing end cap 1-2-7 and the first end face of the external pressure protective gas housing 1-2-5 are sealed by a protective gas shaft seal 1-2-8.

[0218] A gap exists between the inner wall of the external pressure protective gas housing 1-2-5 and the outer wall of the feeding screw 1-4 to form an annular cavity around the feeding screw 1-4. An inlet pipe 1-2-6 and an outlet pipe 1-2-9, penetrating the inside and outside of the external pressure protective gas housing 1-2-5, are provided on the housing so that the annular cavity is connected to the gas source through the inlet pipe 1-2-6 and to the outside of the housing through the outlet pipe 1-2-9. Optionally, the lateral length of the annular cavity is 0.5–8 mm. In this disclosure, the lateral length of the annular cavity represents its length along the length of the screw.

[0219] In one implementation, such as Figure 2 and Figure 6 As shown, a pressure sensor and a first control valve are installed on the protective gas inlet pipe 1-2-6; a back pressure valve is installed on the protective gas outlet pipe 1-2-9, which can regulate the pressure inside the cavity.

[0220] The pellet feeder housing 1-2-1 is sleeved outside the feeding section of the feeding screw 1-4, and the first end face of the pellet feeder housing 1-2-1 is sealed with the second end face of the external pressure protective gas housing 1-2-5 by the feeding shaft seal 1-2-2;

[0221] The inlet end of the standpipe 1-5 is connected to the conveying section of the feeding screw 1-4, and the outlet end extends into the housing of the regenerator 2-1.

[0222] This disclosure incorporates an external pressure protective gas structure within the feeding screw. The principle of this structure is as follows: a small-volume cavity combined with a trace amount of gas generates high pressure. This high-pressure gas micro-clusters externally seal the tiny gaps that appear on the rotating shaft of the automatic particle feeder (feeding screw) during operation, preventing gas leakage from the inside out through these minute pores. This device not only prevents reaction gas leakage but also prevents dry, hot fine powder from entering the tiny pores of the sealing surface, thus avoiding aging and failure of the sealing material. Furthermore, due to the increased length of the conveying section, problems such as bridging, increased friction loss, particle compression, and increased particle wear occur during particle conveying. This disclosure utilizes the trace amount of gas flowing into the system through the external pressure protective gas structure to widen the particle spacing, increase material flowability, and improve conveying efficiency, effectively solving the problems caused by the increased length of the conveying end. The trace amounts of gas in the external pressure protective gas structure will not cause significant interference to the flow field and reactant concentration inside the regenerator, and the impact caused by the external pressure protective gas structure can be ignored. The external pressure protective gas uses nitrogen or inert gas, which can ensure that the solid material will not be contaminated or reacted by gaseous components that diffuse or back up from downstream during the transportation and heating process.

[0223] The feeding screw in this disclosure, in conjunction with the external pressure protection gas structure installed at the coupling end, achieves the effect of stable material delivery from the feeder into the regenerator.

[0224] In one implementation, such as Figure 2 As shown, the feeding screw 1-4 also includes a feeding inlet and a feeding outlet, which are located in the pellet feeder housing 1-2-1. The feeding inlet is connected to the outlet of the regenerator hopper 1-1, and the feeding outlet is connected to the regenerator inlet of the regenerator 2-1. Along the material transmission direction of the feeding screw 1-4, the feeding inlet is located downstream of the shaft seal 1-2-2 and is spaced from the shaft seal 1-2-2 to form an empty section. Preferably, the length of the empty section of the feeding screw 1-4 is 50-300 mm.

[0225] This disclosure leaves an empty section before the feeding area, which can reduce the temperature rise of the rotating shaft caused by the preheating of the conveying section and protect the flexible sealing material at the shaft seal. At the same time, the empty area can also play a buffering role in special circumstances of the device, such as blockage of the balance pipe, insufficient external pressure protection gas pressure, or other reasons that cause the regenerator pressure to be much greater than the automatic particle feeder pressure, to prevent backflow gas from carrying a large number of particles to directly impact the shaft seal and damage the sealing structure.

[0226] In one implementation, such as Figure 2As shown, a solid preheater 1-3 is fitted outside the conveying section of the feeding screw 1-4 to form a preheating section for the regenerator on the feeding screw 1-4. There is a gap between the preheating inlet of the solid preheater 1-3 and the feeding inlet of the feeding screw 1-4, and the feeding outlet of the feeding screw 1-4 is located in the regenerator preheating section. By installing a solid preheater outside the feeding screw, the regenerator can be heated to the target temperature before entering the regenerator, improving the reaction efficiency within the subsequent regenerator and avoiding large temperature fluctuations inside the regenerator, which is beneficial for steady-state simulation operation.

[0227] In one specific embodiment, the total length of the conveying section of the feeding screws 1-4 is 200-1000 mm. In this disclosure, the total length of the conveying section between the feeding inlet and the feeding outlet is relatively long, and the specific length can also be adjusted according to the particle preheating requirements and the power of the heating furnace to maintain the final particle discharge temperature at 10-550°C.

[0228] In a preferred embodiment, such as Figure 8 As shown, the idle section and conveying section of the feeding screw 1-4 have an inclination angle, preferably any inclination angle between -30° and 30°. In this disclosure, the inclination angle at which the feeding outlet is higher than that at the feeding inlet is considered positive.

[0229] The automatic feeding device (feeding screw) used in this disclosure is set with an inclination angle. When feeding particles with good flowability, the conveying section is installed with an appropriate upward inclination (0 to 30°) to increase feeding stability; when feeding particles with poor flowability, it needs to be appropriately tilted downward (-30 to 0°) to increase flowability.

[0230] In one implementation, such as Figure 2 As shown, the outlet end of the riser 1-5 is located above the heat exchange medium inner component 2-5 and is spaced apart from the top of the heat exchange medium inner component 2-5. In one specific embodiment, as... Figure 2 As shown, the height of the static bed of regenerating agent in regenerator 2-1 is higher than the top of the heat exchange medium internal component 2-5, so that the heat exchange medium internal component 2-5 is completely placed in the regenerating agent bed. The outlet end of the regenerating riser 1-5 is located below the static bed of regenerating agent in regenerator 2-1. Optionally, the outlet end of the regenerating riser 1-5 is located 10-50 mm below the static bed of regenerating agent in regenerator 2-1, and is spaced apart from the top of the heat exchange medium internal component 2-5. This disclosure positions the outlet end of the regenerating riser 1-5 below the static bed of regenerating agent in regenerator 2-1, which serves a sealing function.

[0231] In one specific implementation, such as Figure 2As shown, the system also includes a heating furnace 2-2, which is located outside the regenerator 2-1; optionally, the number of heating furnaces 2-2 can be one or more. During the evaluation test, this disclosure allows the regenerator to be heated by the heating furnace to maintain a stable internal temperature.

[0232] In one implementation, such as Figure 2 As shown, the system also includes a coking gas supply unit, which includes a pressure regulating valve 4-1, a gas flow meter 4-2, a gas preheater 4-3, and a gas distributor 2-6.

[0233] The gas preheater 4-3 is provided with a gas preheating inlet and a gas preheating outlet. The gas preheating inlet is connected to the coking gas source. On the gas source inlet pipeline of the gas preheating inlet, a pressure regulating valve 4-1 and a gas flow meter 4-2 are arranged in sequence along the gas flow direction. In this disclosure, the gas flow meter 4-2 is used to monitor the coking gas inlet flow rate, and the coking gas flow rate is controlled by adjusting the opening of the pressure regulating valve 4-1.

[0234] The gas distributor 2-6 is provided with a coking gas inlet and a distribution port. The coking gas inlet is connected to the preheated gas outlet of the gas preheater 4-3. The gas distributor 2-6 extends from the lower part of the shell of the regenerator 2-1 into the regenerator 2-1. The outlet of the distribution port of the gas distributor 2-6 faces the bottom of the shell of the regenerator 2-1.

[0235] In a preferred embodiment, the gas distributor 2-6 extends from the bottom of the upper cylindrical shell of the regenerator 2-1 into the regenerator 2-1, and the outlet of the distribution vent of the gas distributor 2-6 faces the bottom of the lower conical shell of the regenerator 2-1.

[0236] In the system provided in this disclosure, the coking gas is controlled to reach the target flow rate by a pressure regulating valve and a gas flow meter, heated by a gas preheater, and uniformly injected downwards into the regenerator through a gas distributor. Under the combined action of cone bottom reflection and pressure gradient, the flow direction changes to bottom to top. During the upward flow, it comes into contact with solid particles, which can make the solid particles fluidized under the action of the coking gas and carry out coking regeneration.

[0237] The gas distributor 2-6 used in this disclosure can adopt a conventional structure in the art. In one specific embodiment, the gas distributor 2-6 is an annular hollow tube structure.

[0238] In one implementation, such as Figure 2As shown, the system also includes an analysis unit; the analysis unit includes a flue gas sampling device 5-5 and a tail gas analyzer 5-4; the regenerator 2-1 also includes a flue gas filtration device 2-3, which is located in the upper part of the regenerator 2-1 housing; the flue gas inlet of the tail gas analyzer 5-4 is connected to the flue gas outlet of the flue gas filtration device 2-3.

[0239] The regenerator 2-1 has a flue gas collection port on its shell side wall, which is connected to the flue gas sampling device 5-5. Preferably, multiple flue gas collection ports are provided at different heights on the shell side wall along the axial direction of the regenerator 2-1.

[0240] In one specific embodiment, two or more sampling ports are set at different heights in the dense phase section of the regenerator; and two or more sampling ports are set in the dilute phase section. In an exemplary embodiment, such as... Figure 7 As shown, a sampling port (taking one sampling port as an example) is provided on the side wall of regenerator 2-1. The sampling inlet of flue gas sampling pipe 5-5-1 enters the interior of regenerator 2-1 through the sampling port. A filter 5-5-3 is provided at the head of flue gas sampling pipe 5-5-1, and a temperature sensor 5-5-2 is installed inside. Flue gas sampling pipe 5-5-1 is also connected to pressure sensor 5-5-4 and gas sampling bag 5-5-6. Through the pressure sensor and temperature sensor connected to flue gas sampling pipe 5-5-1, the pressure and temperature at different bed heights inside the regenerator can be monitored, which facilitates the control of the steady-state environment inside the regenerator. Flue gas sampling pipe 5-5-1 is also provided with flue gas sampling valve 5-5-5 to facilitate the control of flue gas sampling.

[0241] In one implementation, such as Figure 2 As shown, the system also includes a regenerant recovery unit; the regenerant recovery unit includes a discharge valve 3-1, a discharge hopper 3-2, a discharge hopper air inlet valve 3-3, a discharge hopper back pressure valve 3-4, a pressure sensor 3-5, and a discharge valve 3-6; the discharge hopper 3-2 is provided with a regenerant inlet, a discharge outlet, a discharge hopper air inlet, and a discharge hopper gas outlet; the regenerant inlet is connected to the regenerant outlet of the regenerator 2-1; the discharge hopper air inlet is located at the upper part of the discharge hopper 3-2, and the discharge hopper air inlet valve 3-3 is provided on the connecting pipeline between the discharge hopper air inlet and the gas source;

[0242] The gas outlet of the discharge hopper is located at the top of the discharge hopper 3-2 and is connected to the external environment through a gas outlet pipeline. A back pressure valve 3-4 for the discharge hopper is installed on the gas pipeline, and a pressure sensor 3-5 is installed between the gas outlet of the discharge hopper and the back pressure valve 3-4. The discharge rate, bed stock volume, and bed height are adjusted by controlling the pressure difference between the inside of the discharge hopper and the inside of the regenerator.

[0243] In one specific embodiment, during the regeneration simulation reaction process, the method includes: allowing the regenerating agent to enter the regenerator 2-1 through the feeding outlet of the regenerating agent feeding unit; and introducing coking gas into the regenerator 2-1 through the coking gas supply unit, and performing coking regeneration treatment on the regenerating agent in the regenerator 2-1 to obtain regenerated flue gas and regenerating agent.

[0244] The heat exchange medium is introduced into the variable diameter spiral coil tube through the heat exchange medium inlet of the heat exchange medium internal component 2-5, so that the heat exchange medium exchanges heat with the material in the regenerator 2-1.

[0245] The regenerated flue gas is sent to the analysis unit for analysis; the regenerant is sent to the regenerant recovery unit for regenerant recovery treatment.

[0246] Preferably, the oxygen volume content in the coking gas is 0-100%, more preferably 0.5-25%;

[0247] The reaction conditions within the regenerator include: a temperature of 500–800°C, a pressure of 0.01–0.6 MPa, preferably 0.2–0.5 MPa, and a volume hourly space velocity (VHSV) of 6–50,000 h⁻¹ for the coking gas. -1 Preferably 200-3000h -1 The residence time of the heat exchanger is 1–240 min, preferably 2–60 min; the heat exchange medium can be any one of air, deionized water, and molten salt, wherein the molten salt can be a binary nitrate, for example, the binary nitrate includes 50–70 wt% KNO3 and 30–50 wt% NaNO3; when the heat exchange medium is air, the inlet temperature is 5–30 °C and the pressure is 0–0.2 MPa; when the heat exchange medium is deionized water, the inlet temperature is 40–150 °C and the pressure is 0–4 MPa; when the heat exchange medium is molten salt, the inlet temperature is 250–350 °C and the pressure is 0–0.2 MPa.

[0248] Optionally, the oxygen content in the coking gas composition is 10-40% by volume.

[0249] In one specific embodiment, the feeding screw in the regenerator feeding unit feeds the regenerator at a rate of 0.1–20 g / s, and the working pressure of the feeding screw in the regenerator feeding unit is 0–0.5 MPa. In this disclosure, the working pressure of the feeding screws 1-4 refers to the air pressure inside the screw housing during screw transmission.

[0250] In one exemplary embodiment, the following is adopted: Figure 2 The specific process flow of the continuous catalytic cracking regeneration operation simulation and evaluation system shown includes:

[0251] The pre-regenerating agent in the pre-regenerating agent silo 1-1 is fed into the feeding screw 1-4 through the feeding inlet, and then automatically fed to the feeding outlet under the action of the screw. During the automatic feeding process of the pre-regenerating agent, protective gas is introduced into the cavity of the external pressure protective gas structure. The pre-regenerating agent is preheated through the pre-regenerating agent preheating section of the feeding screw 1-4, and then enters the regenerator 2-1 through the pre-regenerating riser 1-5.

[0252] The coking gas passes sequentially through the pressure regulating valve 4-1, the gas flow meter 4-2, and the gas preheater 4-3. The preheated coking gas at the target flow rate is injected into the bottom of the lower conical shell of the regenerator 2-1 through the distribution holes on the gas distributor 2-6. Under the combined action of the cone bottom reflection of the lower conical shell and the pressure gradient, the flow direction changes to bottom to top. During the upward flow, it comes into contact with solid particles (regenerating agent), and the regenerating agent undergoes coking regeneration to form regenerated flue gas and regenerating agent. During the coking regeneration process, heat exchange medium is introduced into the heat exchange medium inlet of the heat exchange medium internal component 2-5 in the form of a variable diameter spiral coil inside the regenerator 2-1. The heat exchange medium after heat exchange is led out through the heat exchange medium outlet.

[0253] Sampling of the flue gas is performed through sampling ports on the side wall of the regenerator, and parameters such as pressure and temperature at different bed heights can also be monitored. After a portion of the regenerated flue gas rises to the top of the regenerator 2-1, it is filtered by the flue gas filtration device 2-3 and then enters the tail gas flue gas analyzer 5-4 for flue gas composition analysis.

[0254] The amount of regenerant discharged from regenerator 2-1 is controlled by adjusting the opening and closing degree of discharge valve 3-1 on the discharge pipe of the regenerator. The regenerant enters the discharge hopper 3-2, and the pressure in the discharge hopper and the discharge status of the regenerant are detected and controlled by the discharge hopper air inlet valve 3-3, the discharge hopper back pressure valve 3-4 and the pressure sensor 3-5. The regenerant is led out through the discharge valve 3-6, and parameters such as the carbon content of the regenerant are detected as needed to evaluate the regeneration status.

[0255] In one specific embodiment, during the steady-state preparation process, a balancing agent is pre-set in the regenerator, and then a regenerator is introduced into the regenerator through a regenerator storage and feeding unit to replace the balancing agent. In this process, the input method of the regenerator is the same as that in the simulation evaluation process described above.

[0256] The present disclosure will be further described below with reference to specific embodiments.

[0257] In the following examples and comparative examples, the carbon content of the regenerant was measured by drying the regenerant sample and then sending it to a carbon-sulfur analyzer or an organic element analyzer.

[0258] The concentrations of CO2 and CO in the flue gas are detected in real time by a 5-4 tail gas flue gas analyzer, and the results are displayed on the computer in real time.

[0259] In the following embodiments, the balancing agent used in the steady-state preparation step was extracted from a catalytic cracking unit of an oil refinery. The balancing agent had an average particle size of 68 μm and a carbon content of 0.08 wt%.

[0260] Example 1

[0261] use Figure 2 The continuous catalytic cracking regeneration operation simulation and evaluation system shown has the following specific device structure:

[0262] The preheating agent silo 1-1 has a volume of 20L. The feeding screw 1-4 is arranged horizontally without any tilt angle. The screw thread is a rectangular thread machined from steel plate with a thread thickness of 1.5mm and a thread pitch of 20mm. The major diameter of the screw is 40mm and the minor diameter is 20mm. The feeding shaft seal and the protective gas shaft seal are made of polytetrafluoroethylene. The lateral length of the unused section of the feeding screw 1-4 is 100mm, and the length of the conveying section is 600mm. The inner diameter of the inlet pipe 1-2-6 of the external pressure protective gas structure 1-2 is 4mm, and the outer diameter is 6mm. The inlet pipe 1-2-6 is connected to an argon gas cylinder and a gas quality controller. The outlet pipe of the external pressure protective gas structure is connected to an electrically controlled needle valve. The lateral length of the annular cavity of the external pressure protective gas structure is 4mm. A solid preheater 1-3 is installed outside the conveying section of the feeding screw 1-4. The outlet of the conveying section is connected to a stand-up regenerator 1-5 with an outer diameter of 12 mm and a wall thickness of 1.5 mm. The stand-up regenerator 1-5 is inserted vertically into the regenerator 2-1 along the axis of the regenerator 2-1. The outlet of the stand-up regenerator 1-5 is located 30 mm below the experimental static bed, where the height of the experimental static bed is 240 mm.The regenerator 2-1 consists of an upper cylindrical shell and a lower conical shell. The inner diameter of the upper cylindrical shell is 60 mm, and its height is 1500 mm, with a height-to-diameter ratio of 25:1. The cone angle of the lower conical shell is 120°. The total height of the regenerator 2-1 shell is 1518 mm. A heating furnace is arranged outside the regenerator 2-1. Two sampling ports along the axial direction on the side wall of the dense phase section of the regenerator 2-1 are connected to flue gas sampling equipment 5-5; one sampling port along the axial direction on the side wall of the dilute phase section is also provided. The configuration is the same as the dense phase sampling port; the flue gas filtration device 2-3 uses a 316 stainless steel metal powder filter with a filtration accuracy of 3μm; the flue gas filtration device 2-3 is externally connected to the regenerator back pressure valve and gas mass flow meter, and finally sent to the flue gas analyzer and tail gas treatment; the regenerator 2-1 is equipped with a heat exchange medium inner component 2-5 made of seamless steel pipe with a variable diameter plate, located 130mm from the upper surface of the gas distributor 2-6 in the middle of the regenerator 2-1. The interior of the heat exchange medium inner component 2-5 is hollow and circulated with cooling water, using a bottom-in, top-out method. The maximum coil diameter of coil 2-5 is 54mm (90% of the inner diameter of the regenerator 2-1 shell), the vertical height is 47mm, the thread pitch of each coil centerline is 10.5mm, the inner diameter of the steel pipe is 4.5mm, and the wall thickness is 2mm; the gas distributor 2-6 at the bottom of the regenerator uses a gas distribution ring made of seamless steel pipe with an outer diameter of 8mm and a wall thickness of 1mm, with 10 1mm diameter openings evenly distributed downwards along the ring; the regenerant outlet at the bottom of regenerator 2-1 is connected to a regenerant with an outer diameter of 12mm and a wall thickness of 1.5mm. A seamless steel pipe is connected to a discharge valve 3-1 and then to a discharge hopper 3-2. One side of the discharge hopper 3-2 is connected to an air inlet pipe with an outer diameter of 8mm and a wall thickness of 1mm, an air inlet valve 3-3, and a nitrogen gas source. The other side of the discharge hopper 3-2 is connected to an air outlet pipe with an outer diameter of 8mm and a wall thickness of 1mm, a pressure sensor 3-5, and a back pressure valve 3-4. The coking gas inlet of the gas distributor 2-6 of the regenerator 2-1 is connected in sequence to a gas preheater 4-3, a gas flow meter 4-2, a pressure regulator 4-1, and a coking gas source.

[0263] The above continuous catalytic cracking regeneration operation simulation and evaluation system was used to perform steady-state preparation, simulated reaction, and effect evaluation in the following steps:

[0264] S1. First, calculate the operating parameters based on the actual dimensions of the device for the target to be simulated.

[0265] The industrial unit to be simulated uses a single-unit, single-stage catalytic cracking regenerator. Specific parameters for the industrial regenerator include: air as the inlet gas, a dense phase temperature of 680℃, and a particle bulk density of 920 kg / m³. 3 The skeleton density is 2650 kg / m³. 3The pre-regenerating agent is an FCC pre-regenerating agent with a carbon content of 0.85% by weight, the regenerator has a carbon content of 0.06% by weight, the bed stock in the regenerator is 185t, the static bed height is 3.4m, the industrial catalyst particle circulation rate is 1632t / h, and the volume hourly space velocity is 706h. -1 The apparent gas velocity is 1 m / s, the carbon dioxide content in the flue gas is 7.2% by volume, the carbon monoxide content is 9.7% by volume, and the residual oxygen content is 4.6% by volume.

[0266] 8 kg of the regenerating agent was dried at 250℃ for 2 h; its composition was measured, yielding Cc = 0.85 wt% and f = 1. The coking gas supply unit was connected to a compressed air cylinder as the coking regeneration gas, with an oxygen content of 21 vol%. Based on this method, the experimental operating parameters for simulating the catalytic cracking regeneration process were determined.

[0267] u1 is determined by the following equation (1-1), and u2 is determined by the following equation (1-2):

[0268]

[0269]

[0270] Where, given U = 1 m / s, u t =0.158m / s, H=3.4m; taking k1=0.85, k2=1.15, h=0.55m, the apparent air velocity u is calculated to be 0.092~0.113m / s.

[0271] The standard intake volume in the experimental operating parameters is determined by the following formula (2):

[0272]

[0273] Where d = 0.06m, ρ s =920kg / m 3 C C =0.85 wt%, r = 4.6 vol%, C CO2 =7.2% by volume, e = 9.7% by volume / 7.2% by volume = 1.347; f = 1, t S =185×1000 / (1632×1000 / 3600) = 408s, so Q = 0.0002917m is calculated. 3 / s=17.5L / min.

[0274] Then, combining the range of apparent gas velocity u in the simulation experiment, the apparent pressure in the regenerator 2-1 in the experimental operating parameters is determined by the following formula (3):

[0275]

[0276] The calculation yields 0.31 ≤ p ≤ 0.386 MPa.

[0277] The particle circulation rate of the regenerant in the experimental operating parameters is determined by the following formula (4):

[0278]

[0279] The calculated value is S' = 3.5 g / s.

[0280] The final experimental operating parameters for evaluating the regenerator 2-1 include:

[0281] Take p = 0.34 MPa, T = 680℃, intake air volume Q = 17.5 L / min, u = 0.1 m / s, S' = 3.5 g / s, ts = 6.8 min, and h = 0.55 m.

[0282] S2. Prepare the regenerator for steady-state operation.

[0283] With a bulk density of 880 kg / m³ 3 Skeletal density 2650kg / m 3 1.4 kg of FCC balancer was added to reactor 2-1. All instruments were turned on, and the preheating temperature of gas preheater 4-3 was set to 200℃, and the heating temperature of the external heater 2-2 of the regenerator was set to 680℃. The coking gas, controlled by pressure regulator 4-1 and gas flow meter 4-2 to reach the target flow rate (inlet gas volume 17.5 L / min), was heated to 130℃ by gas preheater 4-3 and then evenly injected downwards into regenerator 2-1 through gas distributor 2-6. Under the combined action of cone bottom reflection and pressure gradient, the flow direction changed to bottom to top. During the upward flow, it contacted the solid particles, fluidized the solid particles, and began coking regeneration. The reactor back pressure valve 5-1 at the regenerator filter outlet was adjusted to make the reactor pressure 0.34 MPa. The discharge valve 3-1 was closed, and the pressure of the discharge hopper inlet pipe 3-3 and the discharge hopper back pressure valve 3-4 was adjusted to be consistent with the pressure inside regenerator 2-1 at 0.34 MPa. Then open the discharge valve 3-1, adjust the opening of the discharge valve 3-1 and the pressure of the discharge hopper 3-3, and check the deviation between the preset feeding speed and the actual feeding speed and the actual discharge speed according to the changes in the values ​​of the pressure sensor 5-5-4 on the reactor side wall and the pressure sensor 3-5 on the discharge hopper wall.

[0284] The flow rate of the back pressure valve 3-4 in the discharge hopper after stabilization is △Q2 more than the flow rate of the air inlet valve 3-3 in the discharge hopper, which is calculated by the following formula (4-3):

[0285]

[0286] The calculation shows that △Q2 = 228 ml / min.

[0287] During the steady-state preparation stage, coking gas enters from the coking gas supply unit and comes into contact with the regenerator. The flow rate of the heat exchange medium entering the heat exchange medium internal component 2-5 is controlled by the heat exchanger inlet valve 2-4 to remove excess heat from the reactor and maintain the regenerator bed temperature at a constant 680℃. During the replacement process in steady-state preparation, the regenerator is fed into the regenerator 2-1 in the following ways: the regenerator is stored in the regenerator silo 1-1, driven by the screw rotation of the feeding screw 1-4 and the protective gas from the external pressure protective gas structure 1-2 (the protective gas flow rate is 20ml / min, and the pressure of the external pressure protective gas structure 1-2 is 0.34MPa), and then heated to the target temperature (360℃) by the solid preheater 1-3. It then flows into the regenerator 2-1 along the regenerator riser 1-5 at a feeding rate of 3.5g / s, with the feeding screw operating at a pressure of 0.34MPa.

[0288] The regenerated flue gas flows out from the flue gas filter device 2-3 at the top of the regenerator and is analyzed by the exhaust gas analyzer 5-4. During this process, the gas flow rate, feeding rate, and heat exchanger medium flow rate are adjusted according to the instruments.

[0289] During the experiment, pressure sensor data was collected, stored, and calculated by a computer. Only some calculation results and their application are shown here. When the bed stockpile increases, the bed pressure data is as follows: Figure 9 The computer filters and fits the discrete pressure-time data obtained from the sensor in real time to obtain the true pressure-time curve. At this time, for the 100Hz sampling frequency data, starting from point 0 in the figure, data within a 20s range is taken (i.e., the average value of the a values ​​of all first running cycles obtained within 20s). Within each preset first running cycle time (the first running cycle time is 1s in this embodiment), calculations are performed according to the following formulas (5), (5-1) and (5-2):

[0290] p t =at + b (5-1);

[0291]

[0292]

[0293] The calculated average values ​​over 20 seconds are: a = 3.75, b = 341588.02, p t =3.75t + 341588.02. At this point, a > 1, and the computer can automatically determine that the current state of bed stock increase in the reactor, and adjust the opening of the discharge valve accordingly. The subsequent pressure change over time graph is shown below. Figure 10As shown, the average value within 20 s is calculated at this time: a = -0.4, -1 < a < 1, and it can be judged that the bed layer reaches a steady state.

[0294] In this embodiment, the experimental duration (system operation time threshold) is set to 20 times the average residence time of particles (136 min), which is controlled by a computer control system.

[0295] After continuing to run for the average residence time of particles in 1 industrial unit (6.8 min), the CO2 concentration data in the regenerated flue gas generated by the regenerator 2-1 is continuously acquired. The time interval for collecting the CO2 concentration data is 6 s; and every time a second operation cycle (3 s is taken in this embodiment) passes, the concentration standard deviation σ is calculated based on the obtained multiple CO2 concentration data. CO2 , calculate the flue gas characteristic data (30 data points are used in this embodiment), and obtain the carbon dioxide concentration standard deviation σ. CO2 = 0.949%, and the CO2 concentration-time image curve in the flue gas analyzer rises significantly. It is considered that the reaction has not reached a steady state. At this time, the reaction time counted from the start of steady state preparation of the system is less than the experimental duration (136 min), and the experiment continues to run.

[0296] After 2.5 times the average residence time of particles in an industrial unit (17 min), calculate the flue gas characteristic data and obtain the carbon dioxide concentration standard deviation σ. CO2 = 0.15%, and when the image of the flue gas analyzer is stable, it is proved that the composition of the flue gas pollutants also reaches a steady state, which also indicates that the internal reaction of the regenerator 2-1 bed layer reaches a steady state.

[0297] The replacement is completed, and the steady state preparation stage is completed. When the replacement of the equilibrium catalyst ends, the spent catalyst in the bed layer is 85% by weight of the total amount of particles in the bed layer.

[0298] S3. Under the steady state conditions of the system, continue to let the spent catalyst enter the continuous catalytic cracking regeneration operation simulation evaluation system, carry out a regeneration simulation reaction under the experimental operation parameters, and collect the simulation result data; judge whether the catalytic cracking regeneration operation simulation evaluation system is successfully simulated according to the simulation result data:

[0299] Judge whether the simulation of the flue gas product composition of the simulated regeneration reaction is successful according to the γ value obtained by the following formula (6):

[0300] γ = MAX[|c o2 -c′ o2 / c o2 |,|c co2 -c′ co2 / c co2 |,|c co -c′ co / c co |] Formula (6);

[0301] The calculated simulation characteristic number γ = 0.44%, and γ < 5%, indicating that the simulated state is close to the actual industrial process, thus the simulation was successful.

[0302] S4. After the system simulation is successful, the steady-state evaluation experiment begins. The flue gas sampling device 5-5, the exhaust gas analyzer 5-4, the temperature sensor 5-5-2, and the pressure sensor 5-5-4 perform gas sampling analysis and monitor parameters such as temperature and pressure.

[0303] After the experiment, catalyst particles were collected from the top of the regenerator storage silo and the discharge silo. The carbon content of the catalyst before and after regeneration was analyzed using a carbon-sulfur analyzer and an organic element analyzer. The results showed that the carbon content C2 of the regenerator in this regeneration operation was 0.08% by weight, which is basically the same as the carbon content of the regenerator in the actual device (approximately 0.075 to 0.082% by weight) and less than the evaluation standard of 0.1% by weight in this field. The regeneration effect was qualified.

[0304] The carbonization intensity S of the regeneration experiment is obtained according to the following formula (7). c The value:

[0305]

[0306] S was calculated c = 69.66 kg / (t·h), indicating moderate carbon burning intensity. The corresponding carbon burning intensity S in the regeneration experiment of the industrial plant... c The value is 70 kg / (t·h), indicating that the coking intensity of the method provided in this disclosure is consistent with the coking intensity of industrial equipment.

[0307] The exhaust gas analyzer connected to the regenerator outlet was used to analyze the main components in the regenerated flue gas, including carbon dioxide, carbon monoxide, nitrogen oxides, and sulfur oxides, to obtain the emission characteristics of coking pollutants during the regeneration operation. Gas samples collected during the experiment were sent to a mass spectrometer for steady-state analysis to obtain changes in gas composition during the reaction process. Furthermore, data from various temperature sensors can be used to fit the temperature field within the bed.

[0308] in, Figure 11 This is a curve showing the changes in CO2 and CO concentrations in the regenerated flue gas over reaction time, as measured during the experiment in this embodiment. Figure 11It can be seen that when the pre-laid catalyst was replaced in the early stage of the evaluation operation, the concentrations of CO2 and CO in the flue gas gradually increased and then tended to stabilize. After stabilization, the CO2 concentration in the flue gas stabilized at 9.7 vol% (±0.1 vol%) and the CO concentration stabilized at about 7.2 vol% (±0.1 vol%). The flue gas composition values ​​after stabilization are consistent with the flue gas data provided by the industrial unit (in the industrial regenerated flue gas data provided by the oil refinery, CO and CO2 account for 7 vol% and 10 vol% of the total flue gas volume, respectively).

[0309] The coking effect and regeneration depth can also be evaluated by analyzing numerical values ​​such as CO2 and CO concentration in the regenerated flue gas. For example, the CO concentration is too high in this embodiment, which indicates that the regeneration effect is not good for this regeneration process. There is unreacted CO in the flue gas emission. Consider using a post-coking canister or adding a CO combustion aid to convert CO into CO2.

[0310] Example 2

[0311] The difference between this embodiment and Embodiment 1 is that, before loading the preheating agent into the preheating agent silo, a platinum-based CO combustion improver is added to the preheating agent, wherein the concentration of the combustion improver is 2% by weight. The remaining operations are the same as in Embodiment 1.

[0312] Figure 12 This is a curve showing the change of CO2 and CO concentrations in the regenerated flue gas with reaction time, as measured during the experiment in this embodiment.

[0313] contrast Figure 12 and Figure 11 As can be seen, the CO concentration in the regenerated flue gas decreased while the CO2 concentration increased, indicating that the addition of platinum-based CO combustion improver is effective in reducing CO emissions from the regenerated flue gas of the target device. Simultaneously, the bed temperature increased during the experiment. This is reflected in the increased circulation of the heat-extracting medium in this embodiment to maintain the bed temperature compared to Example 1. This phenomenon occurs because in Example 1, the coke on the catalyst underwent incomplete combustion, generating a large amount of CO. The heat released was less than that released when CO2 was generated through complete combustion. After adding the CO combustion improver, the coking situation improved, thus increasing the heat release. No significant changes were observed in other indicators.

[0314] The evaluation results of this embodiment are as follows: using platinum-based CO combustion improver can reduce the CO generation in the flue gas during the regeneration process. However, attention should be paid to the heat balance in the industrial regeneration device, and the heat extraction needs to be increased.

[0315] Example 3

[0316] The difference between this embodiment and embodiment 1 is that the feeding screw 1-4 does not have an empty section, nor does it have an external pressure protection gas structure 1-2. The feeding screw only includes a feeding section and a transmission section, and the length of the transmission section is the same as in embodiment 1. The rest of the parts and operating parameters are the same as in embodiment 1.

[0317] The experimental results of this embodiment show that the carbon content of the regenerator begins to decrease significantly after 20 minutes. Simultaneously, data from the in-bed pressure sensor shows a sudden drop in pressure at all monitoring points within the bed after 18 minutes, with a decrease in bed pressure drop. However, the screw speed and coking gas flow rate remained unchanged during operation, indicating a feeding blockage. Analysis revealed that this phenomenon was caused by gas leakage at the dynamic seal, leading to backflow of catalyst particles in the screw conveyor section and the standby pipe, resulting in feeding blockage, reduced bed stock, increased particle residence time and oxygen-to-carbon ratio, and ultimately, a decrease in the carbon content of the regenerator. A shutdown inspection revealed that the device, which had passed the airtightness test successfully before the experiment, had begun to leak severely from the feeder shaft seal. This indicates that devices without an empty section and external pressure protection gas structure are prone to feeding problems and poor evaluation results. Furthermore, the higher the pressure and reaction temperature inside the reactor, the earlier and more likely this problem will occur.

[0318] Example 4

[0319] The difference between this embodiment and Embodiment 1 is that: instead of performing a steady-state preparation step, after calculating the experimental operating parameters, the generating agent is directly delivered into the empty reactor to conduct a simulation experiment.

[0320] The experimental results of this embodiment show that the flue gas analyzer only detected significant CO release 10 seconds after the addition of the pre-treatment agent. Because the initial temperatures of the pre-treatment agent and gas entering the reactor were far below the reaction temperature, even when the external heating furnace heated the reactor to the reaction temperature, the catalyst particles underwent a prolonged heating period before reacting, and the reaction rate was low, resulting in a negligible CO2 concentration in the flue gas. This consumes more experimental time and materials to achieve a steady state of chemical reaction within the bed. Furthermore, it may lead to the accumulation of high-carbon particles within the reactor, causing a sudden reaction after reaching a certain temperature, resulting in a rapid temperature increase and potentially dangerous conditions. Additionally, to achieve particle accumulation within the bed, the discharge valve needs to be closed; otherwise, the catalyst particles will flow directly out of the empty reactor. After a period of feeding (average residence time of one particle is 408 seconds), the bed density approaches the target value. Opening the discharge valve requires a longer adjustment time and consumes more pre-treatment material to stabilize the bed fluidization state. Therefore, a steady-state preparation step is necessary for a smoother and gentler transition to steady state.

[0321] Comparative Example 1

[0322] When evaluating regeneration using a common fixed fluidized bed reactor, regardless of the reactor type and size, the composition of the influent gas, or the principle and precision of the post-treatment instruments, an intermittent operation is always employed. Comparative Example 1 uses the same reactor structure and dimensions as Example 1, along with the same reactants. The difference from Example 1 is the use of an intermittent operation: 1400g of the pretreated regenerator, similar to that in Example 1, is weighed before the reaction and placed into the regenerator, without continuous catalyst feeding. The temperature and pressure are first increased to the same level as in Example 1 under a nitrogen or inert gas atmosphere. Then, the reaction is carried out using the same coke gas as in Example 1, and the flue gas composition is analyzed.

[0323] The results after a period of reaction are as follows Figure 13 It can be seen that the concentrations of CO2 and CO in the flue gas are constantly changing as the reaction proceeds, first increasing and then decreasing. The carbon content of the catalyst particles in the reactor also continuously decreases until the reaction ceases. This is completely different from the continuous and stable state in actual catalytic cracking regeneration processes, where the reactor temperature, pressure, flue gas composition at the reactor outlet at different times, and the gas-solid two-phase chemical composition (including oxygen partial pressure, pollutant concentration, and catalyst carbon content) in the same region of the reactor at different times are all maintained in a dynamic equilibrium state with slight fluctuations within a certain range (e.g., Figure 11 As shown in Table 12), the specific values ​​of the flue gas composition in this comparative example can be seen in Table 1.

[0324] Compared with Example 1, in Example 1, the concentration of flue gas pollutants reached a steady state and remained constant after a period of increase, with CO2 concentration stabilizing at 9.7% vol% and CO concentration stabilizing at around 7.2% vol% (±0.1%). However, in Comparative Example 1, CO2 and CO concentrations, after reaching their maximum values ​​of 14.8% vol% and 6.1% vol%, respectively, began to decrease until the signals disappeared.

[0325] Therefore, it is clear that the device and method in Comparative Example 1 cannot achieve continuous steady-state simulation, operation preview, and optimization guidance for industrial regeneration equipment. If the data corresponding to the peak value is used, it obviously does not conform to the general chemical reaction law; the CO2 / CO ratio is 15 / 6, which is different from the data of 10 / 6.5 given by the refinery, and it is difficult to represent the actual regeneration process.

[0326] Table 1

[0327]

[0328] Comparative Example 2

[0329] The difference between Comparative Example 2 and Example 1 is that the device structure uses a scaled-down design of the industrial regenerator, with a dense phase section of 60 mm; the evaluation method uses the same apparent gas velocity of 0.8 m / s as the industrial regenerator. The operating parameters that can be calculated at this time include: gas flow rate (standard conditions) 80 L / min; regenerator circulation rate 8 g / s; bed stock 2400 g; and static bed height 943 mm.

[0330] Based on fundamental fluidization knowledge, for a bed of typical Class A granular FCC catalyst with a diameter of 60 mm and a height of 943 mm, at an apparent gas velocity of 0.8 m / s, the bubble diameter can reach 125 mm, far exceeding the 60 mm bed diameter. This inevitably leads to abnormal fluidization phenomena such as large bubbles or even spurting, which severely affects regeneration efficiency and poses a danger. Furthermore, experiments conducted at a feed rate of 8 g / s, a two-hour evaluation test, will consume 57 kg of regenerator, requiring a 64 L storage and discharge silo.

[0331] In summary, if the experiment is scaled up using the same operating conditions as industrial regenerators, several problems will arise, including abnormal fluidization operation, operational hazards, poor regeneration effect, and the consumption of regeneration agents and the huge land area required.

[0332] Comparative Example 3

[0333] The method and system are similar to those in Example 1, except that:

[0334] No heat exchange medium internal components are installed inside the shell of regenerator 2-1. All other operating parameters are the same as in Example 1.

[0335] The results of this comparative experiment show that due to the slow heat dissipation of the bed, the bed temperature became excessively high as the experiment progressed (reaching over 810℃ as measured by the temperature sensor), resulting in a charring rate higher than in the actual industrial process. Therefore, the carbon content of the regenerator obtained in this comparative experiment (0.056 wt% after 40 minutes of reaction) is lower than the 0.075–0.082 wt% range observed in the industrial process, indicating that this comparative experiment cannot accurately simulate and evaluate the regeneration process. Furthermore, this operation also carries certain risks; the experiment should be stopped immediately if the temperature shows a tendency to exceed the limit.

[0336] Comparative Example 4

[0337] The method and system are similar to those in Example 1, except that:

[0338] A constant diameter spiral coil with a winding diameter of 54 mm is installed inside the shell of regenerator 2-1. The parameters such as vertical height and thread pitch of the coil center line are the same as in Example 1. The heat exchange medium is also introduced from bottom to top. The remaining operating parameters are the same as in Example 1.

[0339] The results of this comparative experiment show poor regeneration performance. The carbon content of the regenerator (0.14 wt% after 40 min of reaction) is higher than the 0.1 wt% carbon content required by the catalytic cracking process, resulting in poor regeneration. This is because the constant-diameter spiral coil only serves a heat exchange function and has virtually no effect on improving fluidization quality. Therefore, problems such as poor gas-solid contact and excessively wide particle residence time distribution occur in the bed. The poor regeneration and high carbon content of the regenerator are manifestations of these problems. Therefore, this comparative example cannot accurately simulate and evaluate the regeneration process.

[0340] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0341] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0342] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for simulating catalytic cracking regeneration process and evaluating regeneration effect, characterized in that, Includes the following steps: The experimental operating parameters for simulating the catalytic cracking regeneration process are determined, wherein the experimental operating parameters include: the apparent gas velocity of the coke gas, the standard inlet gas flow rate of the coke gas, the apparent pressure inside the regenerator, and the particle circulation rate of the regenerator regenerant. The spent agent is introduced into a continuous catalytic cracking regeneration operation simulation and evaluation system, and a regeneration simulation reaction is carried out under the experimental operating parameters. Simulation result data is collected, and the success of the regeneration simulation reaction is determined based on the simulation result data. The continuous catalytic cracking regeneration operation simulation and evaluation system includes a feed unit for the regenerator and a regenerator (2-1). The regenerator (2-1) includes a shell, a regenerator inlet, a heat exchange medium internal component (2-5), a coking gas inlet, and a regenerator outlet; wherein the heat exchange medium internal component (2-5) is formed as a variable diameter spiral coil and is coiled around the regenerator (2-1) inside the shell. The heat exchange medium internal component (2-5) includes a heat exchange medium inlet and a heat exchange medium outlet; the heat exchange medium inlet and the heat exchange medium outlet are respectively extended to the outside of the regenerator (2-1) shell through pipelines, so that the heat exchange medium in the heat exchange medium internal component (2-5) tube exchanges heat with the material inside the regenerator (2-1) shell only through the tube wall; The apparent gas velocity u is within the numerical range represented by [u1, u2]; the method also includes determining u1 by the following equation (1-1) and determining u2 by the following equation (1-2): Equation (1-1); Equation (1-2); Where k1 is selected from any value between 0.8 and 0.9; k2 is selected from any value between 1.1 and 1.2; In equations (1-1) and (1-2), h represents the static height of the bed in the regenerator (2-1), m; U represents the apparent gas velocity of the coking gas in the industrial regenerator, m / s; H represents the static height of the bed in the industrial regenerator, m; u1 and u2 represent the apparent gas velocities of the coking gas required for the simulation experiment, m / s; u t The terminal velocity of industrial coking gas is expressed in m / s. The method also includes determining the standard intake volume in the experimental operating parameters by means of the following equation (2): Equation (2); Where Q represents the standard intake volume, m 3 / s; d represents the inner diameter of the dense phase section of the regenerator (2-1), in meters; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 C c The carbon content of the reactant is expressed as % by weight; r represents the volume concentration of oxygen in the flue gas during the industrial regeneration process, expressed as % by volume; e represents the volume ratio of carbon monoxide to carbon dioxide in the industrial regeneration flue gas; f represents the hydrogen-to-carbon molar ratio on the reactant; t s C represents the average residence time of particles in an industrial regenerator, in seconds. CO2 This indicates the volume concentration of CO2 in the regenerated flue gas; The method also includes determining the apparent pressure within the regenerator in the experimental operating parameters by means of the following equation (3): Equation (3); Where p represents the required apparent pressure within the regenerator, MPa; T represents the bed temperature inside the industrial regenerator, °C; d represents the inner diameter of the dense phase section within the regenerator (2-1), m; u represents the apparent gas velocity of the coking gas in the simulation experiment, m / s; and Q represents the standard inlet flow rate of the coking gas, m³ / s. 3 / s; The method also includes determining the particle circulation rate of the regenerant in the experimental operating parameters by means of the following equation (4): Equation (4); Where S' represents the required particle circulation rate of the regenerant, g / s; h represents the static bed height of the regenerator (2-1), m; d represents the inner diameter of the dense phase section of the regenerator (2-1), m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 ;t s This represents the average residence time of particles in an industrial regenerator, expressed in seconds.

2. The method according to claim 1, characterized in that, The particle circulation rate S' is 30-70% of the maximum feeding rate of the pre-fermenting agent.

3. The method according to claim 1, characterized in that, The method further includes: performing steady-state preparation on the catalytic cracking regeneration operation simulation and evaluation system; Once the catalytic cracking regeneration operation simulation evaluation system reaches steady-state conditions, the regenerator is introduced into the catalytic cracking regeneration operation simulation evaluation system and the regeneration simulation reaction is carried out; wherein the steady-state conditions include: the bed stock in the regenerator (2-1) reaches steady state and the composition of pollutants in the regenerated flue gas reaches steady state.

4. The method according to claim 3, characterized in that, The steady-state preparation includes the following steps: A balancing agent is pre-placed in the regenerator (2-1), and then coking gas is introduced into the regenerator (2-1) to fluidize the balancing agent; and the bed of the regenerator (2-1) is heated to a higher temperature. When the bed temperature inside the regenerator (2-1) reaches 650~750℃, the regenerating agent is introduced into the regenerator (2-1) through the regenerating agent feeding unit, and the balancing agent in the regenerator (2-1) flows out through the regenerating agent outlet at the bottom of the regenerator (2-1) to replace the balancing agent.

5. The method according to claim 4, characterized in that, The balancing agent has an average particle size of 60-90 μm and a carbon content of 0.01-0.2% by weight; the pre-generation agent has an average particle size of 60-90 μm and a carbon content of 0.5-3% by weight.

6. The method according to claim 4, characterized in that, During the replacement process, the flow rate of the regenerating agent is 80-120% of the particle circulation volume S' of the regenerating agent; the replacement time is 1.4-2 times the average residence time of particles in the industrial regenerator.

7. The method according to claim 4, characterized in that, When the amount of the pre-generated agent in the bed is 80-90% by weight of the total amount of particles in the bed, the balancing agent replacement ends.

8. The method according to claim 3, characterized in that, The regenerator (2-1) has multiple sampling ports at different locations on its side wall; The method also includes: during the steady-state preparation process, obtaining the test pressure values ​​at fixed positions within the bed of the regenerator (2-1) at different times through multiple sampling ports of the regenerator (2-1); The pressure data obtained at each fixed location are subjected to the following steps (a) to (c): (a) The test pressure value is processed using the moving average method to obtain the true pressure value; (b) Then, the true pressure-time data at the fixed location is fitted to obtain the true pressure-time fitting curve; (c) During the first operating cycle, the slope value a of the pressure true value-time fitting curve is obtained by the following formula (5), and the bed stock at this position in the regenerator (2-1) is determined to be steady state based on the value of a. Equation (5); N represents the number of pressure data points at a fixed location; p ti This represents the true pressure value at the i-th point at a fixed location, in Pa; t i Let represent the time corresponding to the i-th point, in seconds.

9. The method according to claim 8, characterized in that, When the preset calculation cycle is run continuously, the value of a satisfies: -1≤a≤1, the bed stock in the regenerator reaches a steady state, and the time of the calculation cycle is not less than the time of the first running cycle.

10. The method according to claim 8, characterized in that, The first running cycle takes less than 5 seconds.

11. The method according to claim 9, characterized in that, The preset calculation period is 10~30s.

12. The method according to claim 9, characterized in that, When the preset calculation cycle is run continuously, the value of a satisfies: -0.3≤a≤0.3, the bed stock in the regenerator reaches a steady state, and the time of the calculation cycle is not less than the time of the first running cycle.

13. The method according to claim 10, characterized in that, The duration of the first running cycle is 0.5~2s.

14. The method according to claim 8, characterized in that, Once the bed stock level in the regenerator (2-1) reaches a steady state, the method further includes: Continue running and continuously acquire CO2 concentration data in the regenerated flue gas generated by the regenerator (2-1) during operation; Then, after each second operating cycle, the concentration standard deviation σ is calculated based on the multiple CO2 concentration data obtained. CO2 And according to σ CO2 Determine whether the composition of pollutants in the regenerated flue gas has reached a steady state.

15. The method according to claim 14, characterized in that, When σ CO2 The pollutant composition of the regenerated flue gas reaches a steady state when it is below 0.5%. The second operating cycle is 1~20s; The concentration standard deviation σ CO2 The number of CO2 concentration data points required for the calculation is 10 to 60.

16. The method according to claim 14, characterized in that, Once the bed stock in the regenerator (2-1) reaches a steady state, continue running for 0 to 10 times the average residence time of the industrial unit, and then obtain the CO2 concentration data in the regenerated flue gas.

17. The method according to claim 15, characterized in that, When σ CO2 The pollutant composition of the regenerated flue gas reaches a steady state when the concentration is below 0.2%. The second operating cycle is 1~5s; The concentration standard deviation σ CO2 The number of CO2 concentration data points required for the calculation is 20 to 40.

18. The method according to claim 14, characterized in that, The method also includes: After the bed stock in the regenerator (2-1) reaches a steady state, it is determined whether the first running time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds the running time threshold, wherein the first running time is calculated from the start of steady state preparation. If the first running time does not exceed the running time threshold, the system continues to run; The system stops running when the first running time exceeds the running time threshold; and When σ CO2 When the value is above 0.5%, it is determined whether the second running time of the continuous catalytic cracking regeneration operation simulation evaluation system exceeds the running time threshold, wherein the second running time is calculated from the steady-state preparation start time. If the second running time does not exceed the running time threshold, the system continues to run. The system stops running when the second running time exceeds the running time threshold.

19. The method according to claim 18, characterized in that, The operating time threshold is 10 to 40 times the average residence time of particles in an industrial regenerator.

20. The method according to claim 19, characterized in that, The operating time threshold is 15 to 30 times the average residence time of particles in an industrial regenerator.

21. The method according to claim 1, characterized in that, The simulation results include the concentrations of carbon dioxide and carbon monoxide in the regenerated flue gas. The method of determining whether the regeneration simulation reaction was successfully simulated based on the simulation result data includes: The success of the simulation of the flue gas product composition in the regeneration reaction is determined by the γ value obtained from the following formula (6): Equation (6); When γ < 5%, the simulation is successful; Among them, c o2 This indicates the volume concentration of oxygen in the regenerated flue gas of an industrial plant, expressed as % by volume. c' o2 This indicates the volume concentration of oxygen in the regenerated flue gas in the catalytic cracking regeneration operation simulation and evaluation system, expressed as a percentage of volume (c). co2 This indicates the volume concentration of carbon dioxide in the regenerated flue gas of an industrial plant, expressed as % (c'). co2 The volume concentration of carbon dioxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation evaluation system is expressed as %; c co This indicates the volume concentration of carbon monoxide in the regenerated flue gas of an industrial plant, expressed as % (c'). co This represents the volume concentration of carbon monoxide in the regenerated flue gas in the catalytic cracking regeneration operation simulation and evaluation system, expressed as volume.

22. The method according to claim 1, characterized in that, The method also includes: after a successful simulation, conducting a regeneration experiment of the regenerating agent and collecting regeneration result data; and evaluating the effect of the regeneration experiment based on the regeneration result data.

23. The method according to claim 22, characterized in that, The regeneration result data includes char intensity S. c The evaluation of the regeneration experiment's effectiveness based on the regeneration result data includes: The carbonization intensity S of the regeneration experiment is obtained according to the following formula (7). c The value, and then based on the carbonization intensity S c The effectiveness of the regeneration experiment was evaluated, including S c A higher value indicates a better outcome in the regeneration experiment. Equation (7); Where Sc is in kg / (t·h); C0 represents the carbon content of the regenerator, by weight%; C2 represents the carbon content of the regenerator obtained from the catalytic cracking regeneration operation simulation evaluation system, by weight%; h represents the static height of the bed in regenerator (2-1), in m; d represents the inner diameter of the dense phase section of regenerator (2-1), in m; ρ s This indicates the bulk density of the regenerator in an industrial regenerator, in kg / m³. 3 .

24. The method according to claim 1, characterized in that, The variable diameter spiral coil is formed by winding a through hollow tube in a conical spiral line; and along the axial direction of the regenerator (2-1) shell, the winding diameter of the variable diameter spiral coil gradually increases from top to bottom to form an upright cone, or the winding diameter gradually decreases from top to bottom to form an inverted cone, or multiple variable diameter spiral coils are combined and installed, and the combination and installation methods include: the top of the conical shape of one variable diameter spiral coil is connected to the top of the conical shape of another variable diameter spiral coil, or the bottom of the conical shape of one variable diameter spiral coil is connected to the bottom of the conical shape of another variable diameter spiral coil.

25. The method according to claim 24, characterized in that, The inner diameter of the variable diameter spiral coil is 3~8mm, and the thread pitch of the center line of each layer of coil is 3~15mm; the wall thickness of the variable diameter spiral coil is 0.75~2mm. The maximum winding diameter of the variable diameter spiral coil is 80-95% of the inner diameter of the regenerator (2-1) shell, wherein the maximum winding diameter refers to the maximum diameter of the conical shape of the variable diameter spiral coil. The hollow tube is a seamless steel pipe.

26. The method according to claim 25, characterized in that, The hollow tube is either round or rectangular.

27. The method according to claim 1, characterized in that, The shell of the regenerator (2-1) is a cylindrical body with a constant diameter or a cylindrical body with a variable diameter; the cross-section of the shell of the regenerator (2-1) is circular.

28. The method according to claim 27, characterized in that, The shell of the regenerator (2-1) is a variable diameter cylinder, which is composed of an upper cylindrical shell and a lower conical shell that are coaxially and sealed together. The heat exchange medium internal component (2-5) is disposed inside the upper cylindrical shell of the regenerator (2-1) and is coaxially disposed with the upper cylindrical shell. The regenerant outlet is located at the bottom of the lower conical shell and is connected to the regenerant recovery unit. The inner diameter of the upper cylindrical shell is 30~100mm; the height-to-diameter ratio is 1~50:1; The bottom cone angle of the lower conical shell is 60~150°.

29. The method according to claim 28, characterized in that, The height-to-diameter ratio of the upper cylindrical shell is 4~30:1; The bottom cone angle of the lower conical shell is 90~120°.

30. The method according to claim 21, characterized in that, The pre-generation agent storage and feeding unit includes a pre-generation agent silo (1-1), a feeding screw (1-4), an external pressure protective gas structure (1-2), and a pre-generation riser (1-5). The feeding screw (1-4) includes an idle section, a feeding section, and a transmission section; The external pressure protective gas structure (1-2) includes an external pressure protective gas shell (1-2-5), a clamping end cap (1-2-7), and a pellet feeder shell (1-2-1). The external pressure protective gas shell (1-2-5) is sleeved on the outside of the empty section of the feeding screw (1-4), and the clamping end cap (1-2-7) is located at the end of the empty section. The clamping end cap (1-2-7) and the first end face of the external pressure protective gas shell (1-2-5) are sealed by a protective gas shaft seal (1-2-8). The inner wall of the external pressure protective gas housing (1-2-5) and the outer wall of the feeding screw (1-4) have a gap to form an annular cavity around the feeding screw (1-4). The external pressure protective gas housing (1-2-5) is provided with an air inlet pipe (1-2-6) and an air outlet pipe (1-2-9) that connect the inside and outside, so that the annular cavity is connected to the air source through the air inlet pipe (1-2-6) and connected to the outside of the external pressure protective gas housing (1-2-5) through the air outlet pipe (1-2-9). The pellet feeder housing (1-2-1) is sleeved outside the feeding section of the feeding screw (1-4), and the first end face of the pellet feeder housing (1-2-1) and the second end face of the external pressure protective gas housing (1-2-5) are sealed by the feeding shaft seal (1-2-2). The inlet end of the standpipe (1-5) is connected to the conveying section of the feeding screw (1-4), and the outlet end extends into the housing of the regenerator (2-1).

31. The method according to claim 30, characterized in that, The transverse length of the annular cavity is 0.5~8mm.

32. The method according to claim 30, characterized in that, The air inlet pipe (1-2-6) is equipped with a pressure sensor and a first control valve; the air outlet pipe (1-2-9) is equipped with a back pressure valve.

33. The method according to claim 30, characterized in that, The length of the unused section of the feeding screw (1-4) is 50~300mm; the total length of the conveying section is 200~1000mm. The outlet end of the standby riser (1-5) is located above the heat exchange medium internal component (2-5) and is spaced apart from the top of the heat exchange medium internal component (2-5), and the inlet end of the standby riser (1-5) is located below the standby agent static bed of the regenerator (2-1).

34. The method according to claim 33, characterized in that, The conveying section of the feeding screw (1-4) is fitted with a solid preheater (1-3); the temperature of the feed agent after being preheated by the solid preheater (1-3) is 10~550℃.

35. The method according to claim 33, characterized in that, The feeding screw (1-4) has an inclined angle along the empty section to the conveying section.

36. The method according to claim 33, characterized in that, The system also includes a heating furnace (2-2), which is located outside the regenerator (2-1).

37. The method according to claim 34, characterized in that, The temperature of the preheated agent after being preheated by the solid preheater (1-3) is 150~500℃.

38. The method according to claim 35, characterized in that, The feeding screw (1-4) has an arbitrary tilt angle between -30° and 30° along the empty section to the conveying section.

39. The method according to claim 36, characterized in that, The number of heating furnaces (2-2) is one or more.

40. The method according to claim 24, characterized in that, The system also includes a coking gas supply unit, which includes a pressure regulating valve (4-1), a gas flow meter (4-2), a gas preheater (4-3), and a gas distributor (2-6). The gas preheater (4-3) is provided with a gas preheating inlet and a gas preheating outlet. The gas preheating inlet is connected to the coking gas source. The gas source inlet pipeline of the gas preheating inlet is provided with the pressure regulating valve (4-1) and the gas flow meter (4-2) in sequence along the gas flow direction. The gas distributor (2-6) is provided with a coking gas inlet and a distribution vent. The coking gas inlet is connected to the gas preheating outlet of the gas preheater (4-3). The gas distributor (2-6) extends from the lower part of the shell of the regenerator (2-1) into the regenerator (2-1). The outlet of the distribution vent of the gas distributor (2-6) faces the bottom of the shell.

41. The method according to claim 40, characterized in that, The temperature of the coking gas after preheating by the gas preheater (4-3) is 10~300℃; The gas distributor (2-6) extends from the bottom of the upper cylindrical shell of the regenerator (2-1) into the regenerator (2-1), and the outlet of the distribution vent of the gas distributor (2-6) faces the bottom of the lower conical shell of the regenerator (2-1).

42. The method according to claim 41, characterized in that, The temperature of the coking gas after preheating by the gas preheater (4-3) is 100~250℃.

43. The method according to claim 1, characterized in that, The system further includes an analysis unit; the analysis unit includes a flue gas sampling device (5-5) and a tail gas analyzer (5-4); the regenerator (2-1) further includes a flue gas filtration device (2-3), which is located in the upper part of the regenerator (2-1) housing; the flue gas inlet of the tail gas analyzer (5-4) is connected to the flue gas outlet of the flue gas filtration device (2-3); The regenerator (2-1) has a flue gas collection port on its housing side wall, and the flue gas collection port is connected to the flue gas sampling device (5-5).

44. The method according to claim 43, characterized in that, Multiple flue gas collection ports are provided at different heights on the side wall of the housing along the axial direction of the regenerator (2-1); The system also includes a regenerant recovery unit, which includes a discharge valve (3-1), a discharge hopper (3-2), a discharge hopper air inlet valve (3-3), a discharge hopper back pressure valve (3-4), a pressure sensor (3-5), and a discharge valve (3-6). The discharge hopper (3-2) is provided with a regenerant inlet, a discharge outlet, a discharge hopper air inlet, and a discharge hopper gas outlet. The regenerant inlet is connected to the regenerant outlet of the regenerator (2-1). The discharge hopper air inlet is located at the upper part of the discharge hopper (3-2), and the discharge hopper air inlet valve (3-3) is provided on the connecting pipeline between the discharge hopper air inlet and the gas source. The gas outlet of the discharge hopper is located at the top of the discharge hopper (3-2) and is connected to the external environment through a gas outlet pipeline. The gas pipeline is equipped with the back pressure valve (3-4) of the discharge hopper, and the pressure sensor (3-5) is installed between the gas outlet of the discharge hopper and the back pressure valve (3-4).

45. The method according to claim 1, characterized in that, In the process of performing a regeneration simulation reaction, the method includes: allowing the agent to enter the regenerator (2-1) through the feeding outlet of the agent feeding unit; and introducing coking gas into the regenerator (2-1) through the coking gas supply unit, and performing coking regeneration treatment on the agent in the regenerator (2-1) to obtain regenerated flue gas and regenerator. A heat exchange medium is introduced into the variable diameter spiral coil tube through the heat exchange medium inlet of the heat exchange medium internal component (2-5), so that the heat exchange medium exchanges heat with the substance in the regenerator (2-1). The regenerated flue gas is sent to the analysis unit for analysis; the regenerant is sent to the regenerant recovery unit for regenerant recovery treatment. The reaction conditions within the regenerator (2-1) include: a temperature of 500~800℃, a pressure of 0.01~0.6MPa, and a volume hourly space velocity (VHSV) of 6~50000h for the coking gas. -1 The residence time of the preservative is 1~240 min.

46. ​​The method according to claim 45, characterized in that, The volume content of oxygen in the coking gas is 0-100%; The reaction conditions within the regenerator (2-1) include: a pressure of 0.2~0.5 MPa; and a volume hourly space velocity (VHSV) of 200~3000 h⁻¹ for the coking gas. -1 The residence time of the preservative is 2-60 minutes. The feeding screw in the pre-regenerating agent feeding unit feeds the regenerator (2-1) at a speed of 0.1~20g / s, and the working pressure of the feeding screw in the pre-regenerating agent feeding unit is 0~0.5MPa.

47. The method according to claim 46, characterized in that, The oxygen content in the coking gas is 0.5% to 25% by volume.

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