Method for synergistic control of turbulent intensity in high temperature zone of carbon black reactor and additive injection

Abstract

The present application relates to the technical field of cooperative control, and specifically discloses a method for synergistically controlling turbulent intensity in a high-temperature zone of a carbon black reactor and additive injection, collecting a rate of change of damper opening and flue gas density in the high-temperature zone, and generating a predicted decay trajectory of main airflow velocity; setting a critical penetration threshold according to cumulative thermal shock data of the furnace lining, and constructing a safe operation channel by taking a dimensionless ratio of additive injection momentum to inertial force of the main airflow as a constraint; introducing the predicted decay trajectory into the safe operation channel to reversely deduce a maximum allowable injection momentum limit value; converting the limit value into a slow descent pressure reduction curve to control gradual reduction of the additive injection speed, and releasing the limit value in a time lag manner when the speed rebounds; collecting a rate of change of temperature field gradient at an outlet of the furnace, comparing the rate of change with a theoretical temperature gradient to dynamically relax the critical penetration threshold and correct a boundary of the safe operation channel, and outputting a final constraint instruction; and the present application realizes time domain matching and active constraint of physical boundaries of the additive injection amount and damper action under all working conditions.

Description

Technical Field

[0001] This invention relates to the field of collaborative control technology, specifically to a method for collaborative control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor. Background Technology

[0002] The turbulence intensity in the high-temperature zone of a carbon black reactor directly affects the uniformity of mixing between the feedstock oil and hot air, thus determining the particle size distribution and structural properties of the carbon black. Existing control methods typically employ turbulence intensity inversion based on virtual sensing technology. This involves acquiring pulsating signals of the high-temperature flow field using differential pressure sensors or acoustic sensors mounted on the furnace wall, and then calculating the real-time turbulence intensity value through spectral analysis or sound velocity variation. Based on this, the control system adjusts the additive injection flow rate in real time according to the instantaneous deviation in turbulence intensity to compensate for fluctuations in the mixing effect.

[0003] In existing collaborative control methods for carbon black reactors, there is an inherent bandwidth difference between the additive metering pump and the main air supply damper in terms of execution response speed, ranging from milliseconds to seconds. This causes the additive momentum to climb to an extreme value before the air volume responds during rapid production reduction, inducing the jet to penetrate the main airflow and impact the opposite furnace wall, causing melting and perforation. Existing methods lack a synchronous matching mechanism for the timing of additive release and the actual action of air volume during the cooling and recovery phase. They also lack a closed-loop relaxation method for dynamic self-correction of the safety boundary based on the measured deviation of the temperature field. As a result, the collaborative control lacks the ability to actively constrain and adaptively correct the physical safety boundary under all operating conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor, so as to solve the problems mentioned above.

[0005] The objective of this invention can be achieved through the following technical solutions: A method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor includes the following steps: S1: Collect the current damper opening change rate and the flue gas density in the high-temperature zone. Based on the damper mechanical inertia duration, superimpose the opening change rate and the density compensation value to generate the predicted attenuation trajectory of the main airflow velocity in the future period. S2: Dynamically set the critical penetration threshold based on the cumulative thermal shock data of the furnace lining, and use the dimensionless comparison value of the additive injection momentum and the inertial force of the main airflow as the control constraint throughout the process to construct a safe operation channel with the critical penetration threshold as the boundary. S3: The predicted attenuation trajectory is introduced into the safe operation channel. Based on the rate of change of the trajectory position in the channel, the maximum allowable injection momentum limit value that the additive can achieve at the current moment is deduced in reverse. S4: Convert the maximum allowable injection momentum limit value into a gradual depressurization curve, control the additive injection speed to gradually decrease along the gradual depressurization curve to below the limit value, and release the injection momentum limit value in a timing sequence that lags behind the start point of the rise when the main airflow speed is detected to rise back to the set percentage. S5: Collect the rate of change of the temperature field gradient at the furnace outlet and compare it with the theoretical temperature gradient corresponding to the predicted attenuation trajectory; when the comparison deviation exceeds the allowable range, dynamically relax the critical penetration threshold, correct the boundary of the safe operation channel with the relaxed threshold, and output the final constraint command.

[0006] As a further aspect of the present invention: the process of generating the predicted attenuation trajectory is as follows: After collecting the damper opening change rate and the flue gas density in the high-temperature zone, the opening change rate is broadened on the time axis according to the damper mechanical inertia duration to generate a time-based displacement sequence that reflects the damper action lag. The flue gas density is converted into the hot friction coefficient of the flow channel wall, and the density compensation value is weighted and corrected using the hot friction coefficient to obtain the hot drag correction coefficient. The time point of each time point in the time base displacement sequence is coupled point by point with the thermal drag correction coefficient on the time axis. The coupling result is used as the attenuation inflection point value of the main airflow velocity at each sampling time in the subsequent time period. The predicted attenuation trajectory is formed by connecting the attenuation inflection point values ​​in sequence.

[0007] As a further aspect of the present invention: the formation process of the safe operation channel is as follows: The temperature fluctuation amplitude and high temperature holding time of the furnace lining wall are collected. The temperature fluctuation amplitude is weighted by the high temperature holding time to generate the erosion resistance degradation coefficient. The product of the initial tolerance limit and the erosion resistance degradation coefficient is set as the dynamic critical penetration threshold. The inertial force flux of the main airflow at each moment is extracted based on the predicted attenuation trajectory. The momentum flux at the additive injection outlet is converted to the inertial force flux of the main airflow point by point to obtain a dimensionless comparison value sequence. Using the dynamic critical penetration threshold as the upper limit boundary and the lowest attenuation inflection point in the predicted attenuation trajectory as the lower limit boundary, the allowable range of the dimensionless comparison value sequence is limited to the upper and lower limits, forming a safe operating channel.

[0008] As a further aspect of the present invention: the inertial flux of the main airflow at each moment is extracted based on the predicted attenuation trajectory, specifically including: The velocity decay rate at the current sampling moment is extracted from the predicted decay trajectory, and the velocity decay rate is matched with the real-time pressure pulsation value of the furnace wall. The pressure pulsation values ​​are accumulated according to the sampling period to obtain the cumulative wall impact. The cumulative wall impact is corrected by the velocity decay rate to eliminate inertial hysteresis error and obtain the inertial impact equivalent at the current moment. The inertial impact equivalent is time-domain broadened according to the velocity decrease ratio at each moment in the predicted decay trajectory, and the broadened inertial impact equivalent is used as the inertial force flux value of the main airflow at each moment.

[0009] As a further aspect of the present invention: the derivation process of the maximum permissible jet momentum limit value is as follows: Read the position coordinates of the predicted attenuation trajectory within the safe operation channel at the current moment, and extract the first distance relative to the upper boundary of the channel and the second distance relative to the lower boundary of the channel. Use the ratio of the first distance to the second distance as the position deviation ratio. The amplitude reduction factor is obtained by dividing the position deviation ratio by the position change rate at the current moment; Multiply the amplitude reduction factor by the allowable jet momentum value at the previous moment, and use the product as the initial amplitude limit value at the current moment; The initial limit value is weighted and smoothed with the limit value at the previous moment, and the smoothed result is used as the maximum allowable jet momentum limit value at the current moment.

[0010] As a further aspect of the present invention: the release of the jet momentum limit value in a timing sequence lagging behind the recovery start point specifically includes: The maximum permissible injection momentum limit is proportionally distributed to each control cycle according to the total depressurization time. The difference between the distributed value of each control cycle and the initial momentum setpoint is used to generate a step-decreasing curve. The pressure reduction is driven by the deviation between the current injection speed of the additive and the limit value at the corresponding moment in the pressure reduction curve, so that the injection speed decreases in a step-like manner cycle by cycle. When the predicted value of the main airflow velocity is detected to rise to the set percentage for three consecutive sampling cycles, the timing zero point is set at the start time of the rise, and after a preset lag time, the limiting value is released step by step according to the remaining percentage of the depressurization process.

[0011] As a further aspect of the present invention: the driving buck execution specifically includes: The difference between the current injection speed of the additive and the limit value at the corresponding moment of the current control cycle in the slow-deceleration and pressure reduction curve is taken as the speed deviation. The speed deviation is divided by the current injection speed to obtain the deviation ratio. When the deviation ratio is positive, the current cycle's voltage reduction step size is generated by multiplying the deviation ratio by the preset maximum reduction base value. Subtract the depressurization step from the current injection speed value to obtain the speed setpoint for the next control cycle; The speed setpoint is used as the execution command output, so that the injection speed approaches the stepped broken line with the pressure reduction step in each control cycle.

[0012] As a further aspect of the present invention: the output final constraint instruction specifically includes: The temperature values ​​of multiple temperature measuring points distributed circumferentially at the furnace outlet are continuously collected. The change in temperature value of each temperature measuring point relative to the previous sampling time is taken as the instantaneous rate of change. All instantaneous rates of change are arranged circumferentially to generate a temperature field gradient rate of change sequence. The main airflow velocity value corresponding to each moment in the predicted attenuation trajectory is mapped to the theoretical temperature change rate. The deviation sequence is obtained by subtracting the corresponding values ​​in the temperature field gradient change rate sequence from the theoretical temperature change rate. The cumulative deviation values ​​that continuously exceed the allowable range in the cumulative deviation sequence are converted into relaxation increments based on the cumulative amount. The threshold threshold after relaxation is then superimposed on the critical penetration threshold. The upper boundary of the safe operation channel is replaced with the relaxed threshold, and the output range of the final constraint command is defined by the replaced upper boundary and the original lower boundary.

[0013] As a further aspect of the present invention: mapping the main airflow velocity values ​​at each moment in the predicted attenuation trajectory to the theoretical temperature change rate specifically includes: The velocity decrease is obtained by subtracting the current velocity value from the previous velocity value in the predicted decay trajectory, and the velocity decay rate is obtained by dividing the velocity decrease by the time interval between the two samplings. The instantaneous frictional temperature rise equivalent is obtained by multiplying the velocity decay rate by the preset high-temperature zone wall friction heat generation coefficient. The instantaneous frictional temperature rise equivalent is superimposed onto the temperature change rate base value of the previous moment, and the superposition result is corrected by the high temperature radiation weighting coefficient and used as the theoretical temperature change rate corresponding to the current moment. By arranging the theoretical temperature change rate at all times in a time series, a theoretical temperature gradient mapping sequence of the same length as the predicted decay trajectory is generated.

[0014] The beneficial effects of this invention are: (1) By incorporating the mechanical inertia duration of the damper into the prediction of the main airflow velocity, a predicted attenuation trajectory for future periods is generated. Combined with the constraints of the safe operation channel, the maximum allowable injection momentum limit of the additive is derived in reverse. This allows the additive depressurization process to be executed gradually along the depressurization curve, effectively eliminating the injection momentum overshoot caused by the additive actuator response being ahead of the damper action in traditional control. This avoids the local melting and perforation caused by the jet penetrating the main airflow and impacting the opposite furnace wall, and extends the service life of the reactor refractory material.

[0015] (2) By using the predicted rise of the main airflow velocity to the set percentage as the trigger condition during the pressure reduction process, and releasing the injection momentum limit value in a time sequence that lags behind the start point of the rise, the recovery time of the additive injection velocity and the actual effect time of the air volume rise are kept aligned in the time domain; at the same time, by comparing the deviation between the measured value and the theoretical value of the temperature field gradient change rate, the dynamic relaxation critical penetration threshold is corrected, and the boundary of the safe operation channel is corrected, so that the final effect constraint command can adapt to the furnace condition drift, ensuring the effectiveness of the collaborative control under all operating conditions. Attached Figure Description

[0016] The invention will now be further described with reference to the accompanying drawings.

[0017] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a flowchart illustrating the formation process of the safe operation channel in this invention; Figure 3 This is a flowchart illustrating the derivation process of the maximum permissible jet momentum limit value in this invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figure 1 As shown, this invention provides a method for the coordinated control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor, comprising the following steps: S1: Collect the current damper opening change rate and the flue gas density in the high-temperature zone. Based on the damper mechanical inertia duration, superimpose the opening change rate and the density compensation value to generate the predicted attenuation trajectory of the main airflow velocity in the future period. S2: Dynamically set the critical penetration threshold based on the cumulative thermal shock data of the furnace lining, and use the dimensionless comparison value of the additive injection momentum and the inertial force of the main airflow as the control constraint throughout the process to construct a safe operation channel with the critical penetration threshold as the boundary. S3: The predicted attenuation trajectory is introduced into the safe operation channel. Based on the rate of change of the trajectory position in the channel, the maximum allowable injection momentum limit value that the additive can achieve at the current moment is deduced in reverse. S4: Convert the maximum allowable injection momentum limit value into a gradual depressurization curve, control the additive injection speed to gradually decrease along the gradual depressurization curve to below the limit value, and release the injection momentum limit value in a timing sequence that lags behind the start point of the rise when the main airflow speed is detected to rise back to the set percentage.

[0020] S5: Collect the rate of change of the temperature field gradient at the furnace outlet and compare it with the theoretical temperature gradient corresponding to the predicted attenuation trajectory; when the comparison deviation exceeds the allowable range, dynamically relax the critical penetration threshold, correct the boundary of the safe operation channel with the relaxed threshold, and output the final constraint command.

[0021] In S1, the current damper opening change rate and high-temperature zone flue gas density are collected. Based on the damper's mechanical inertia duration, the opening change rate and density compensation value are superimposed to generate the predicted attenuation trajectory of the main airflow velocity over the future period, specifically including: When collecting the rate of change of damper opening, the angular displacement sensor installed at the output shaft end of the damper actuator acquires the damper rotation angle signal in real time. The sensor outputs an angle value every 200 milliseconds. The rate of change of opening at the current moment is obtained by subtracting the angle value at the previous sampling moment from the angle value at the current sampling moment and then dividing by 200 milliseconds.

[0022] The density of flue gas in the high-temperature zone is obtained in real time by microwave transmission densitometers installed on both sides of the high-temperature zone of the furnace. The densitometers use the phase offset of the microwave signal after passing through the high-temperature flue gas to convert it into the flue gas density value, and output a density sampling value every two hundred milliseconds.

[0023] When expanding the opening change rate on the time axis based on the mechanical inertia duration of the damper, the mechanical inertia duration of the damper actuator is first obtained. This inertia duration is obtained by dividing the sum of the rotor inertia of the damper drive motor and the rotational inertia of the damper blade by the electromagnetic torque coefficient of the drive motor. In actual operation, this calculated value is taken as six seconds.

[0024] The opening change rate collected at the current moment is used as the initial amplitude. A time window of six seconds is extended backward along the time axis from the current moment. Within this time window, the opening change rate is repeated in a step of one point every 200 milliseconds to form an opening change rate sequence. This sequence keeps the initial amplitude unchanged within 6 seconds. This sequence is used as the time base displacement sequence reflecting the hysteresis of the damper action.

[0025] When converting flue gas density into the hot friction coefficient of the flow channel wall, the flue gas density value at the current moment is taken every 200 milliseconds based on the surface roughness of the flow channel wall in the high-temperature zone of the furnace and the flue gas temperature. This value is then multiplied by a preset equivalent value of the wall roughness, and the product is used as the initial friction coefficient. Subsequently, the initial friction coefficient is corrected for temperature using the ratio of the current flue gas temperature to the reference temperature of 1200 degrees Celsius. The temperature correction coefficient is the square root of the current flue gas temperature divided by the reference temperature. The initial friction coefficient is then multiplied by this temperature correction coefficient to obtain the hot friction coefficient.

[0026] When the density compensation value is weighted and corrected using the thermal friction coefficient, the density compensation value is the difference between the flue gas density at the current moment and the flue gas density at the previous moment, multiplied by the sampling interval, divided by the flue gas density value at the current moment, and then multiplied by the thermal friction coefficient. The product is used as the thermal resistance correction coefficient.

[0027] When coupling the time-base displacement sequence with the thermal drag correction coefficient point by point on the time axis, the amplitude of the rate of change of the opening at the first time point in the time-base displacement sequence is multiplied by the thermal drag correction coefficient at the current time. The product is used as the attenuation inflection point value at that time. Then, the amplitude of the rate of change of the opening at the second time point in the time-base displacement sequence is multiplied by the thermal drag correction coefficient at the next sampling time, and so on. The multiplication operation is completed point by point for each time point. The product result corresponding to each time point is used as the attenuation inflection point value of the main airflow velocity at each sampling time in the subsequent time period.

[0028] Connect the attenuation inflection point values ​​at each sampling time in chronological order, starting from the attenuation inflection point value of the previous time and ending at the attenuation inflection point value of the next time. Connect the adjacent sampling points with straight line segments to form a broken line, which is the predicted attenuation trajectory. This predicted attenuation trajectory covers the predicted values ​​of the main airflow velocity at each sampling time in the next 6 seconds from the current time.

[0029] When the predicted main airflow velocity is detected to have rebounded to a set percentage, this set percentage is taken as 80% of the velocity rebound value in the current predicted decay trajectory reaching the velocity reduction starting point value. This rebound value must meet this condition for three consecutive sampling times to be considered valid. The high-temperature radiation weighting coefficient is preset based on the radiative heat transfer characteristics of the high-temperature zone of the furnace, with a value between 0.6 and 0.8, and is obtained in real-time by looking up a table based on the ratio of furnace wall emissivity to flue gas radiation absorption coefficient.

[0030] Please see Figure 2 As shown, in S2, the critical penetration threshold is dynamically set based on the cumulative thermal shock data of the furnace lining. The dimensionless comparison value of the additive injection momentum and the inertial force of the main gas flow is used as the control constraint throughout the process, constructing a safe operation channel with the critical penetration threshold as the boundary. Specifically, this includes: When collecting the temperature fluctuation amplitude and high-temperature holding time of the furnace lining wall, six thermocouples are embedded at equal intervals along the circumference of the furnace lining wall. Each thermocouple outputs a temperature measurement value every 200 milliseconds. The temperature fluctuation amplitude is obtained by subtracting the temperature value of the previous sampling moment from the temperature value of the current sampling moment. The cumulative time for the temperature value to be continuously higher than 1400 degrees Celsius is taken as the high-temperature holding time. The temperature fluctuation amplitude of each thermocouple at the same sampling moment is multiplied by its corresponding high-temperature holding time to obtain the weighted fluctuation value of each measuring point. The weighted fluctuation values ​​of all measuring points are added together and averaged. Then, the average value is divided by the product of the temperature fluctuation reference value of 100 degrees Celsius and the duration reference value of 360 seconds to obtain the erosion resistance degradation coefficient. The specific calculation process of the erosion resistance degradation coefficient is as follows: ; in, Indicates the erosion resistance degradation coefficient. This indicates the total number of thermocouple measuring points, with a value of 6. Indicates the first The temperature fluctuation amplitude at each measuring point, in degrees Celsius. Indicates the first The duration of high temperature maintenance at each measuring point, in seconds. This represents the baseline value for temperature fluctuations, taken as 100 degrees Celsius. The time reference value is 360 seconds. The formula means that the sum of the products of the temperature fluctuation amplitude of each measuring point and the high temperature holding time, divided by the product of the total number of measuring points and the reference value, yields a dimensionless degradation coefficient, which reflects the cumulative damage degree of the furnace lining material under thermal shock.

[0031] When the product of the initial tolerance limit and the erosion degradation coefficient is set as the dynamic critical penetration threshold, the initial tolerance limit is taken as the critical jet impact pressure value measured at the factory of the furnace lining refractory material, which is 0.8 MPa. The initial tolerance limit of 0.8 MPa is multiplied by the erosion degradation coefficient D, and the product is used as the dynamic critical penetration threshold at the current moment. This threshold decreases adaptively as the thermal shock damage to the furnace lining accumulates.

[0032] When extracting the velocity decay rate at the current sampling moment from the predicted decay trajectory, the current main airflow velocity value and the previous main airflow velocity value in the predicted decay trajectory are taken. The difference between the two is divided by the sampling interval of 200 milliseconds to obtain the velocity decay rate at the current sampling moment. When matching the velocity decay rate with the real-time pressure pulsation value of the furnace wall, a piezoresistive pressure sensor is installed on the wall of the high-temperature zone of the furnace. This sensor outputs a wall pressure value every 200 milliseconds. The pressure pulsation value is obtained by subtracting the pressure value of the previous moment from the current pressure value. The velocity decay rate and the pressure pulsation value are matched one-to-one according to the sampling moment to form a matching relationship.

[0033] When accumulating pressure pulsations over sampling periods, ten sampling periods are traced back from the current moment. The pressure pulsations corresponding to each sampling period within the traced period are summed to obtain the cumulative wall impact. To eliminate inertial hysteresis error by correcting the cumulative wall impact using the velocity decay rate, the ratio of the velocity decay rate at the current moment to the baseline velocity decay rate of 0.05 is taken as the correction coefficient. The cumulative wall impact is divided by this correction coefficient to obtain the equivalent inertial impact at the current moment.

[0034] When broadening the inertial impact equivalent in the time domain according to the velocity decrease ratio at each moment in the predicted decay trajectory, the ratio of the velocity value at each sampling moment after the current moment in the predicted decay trajectory to the velocity value at the current moment is taken. This ratio is used as the velocity decrease ratio at each moment. The velocity decrease ratio at each moment is then multiplied by the inertial impact equivalent at the current moment, and the product is used as the broadened inertial impact equivalent value for each moment. All broadened values ​​are arranged in chronological order to form a sequence of main airflow inertial force flux values ​​for each moment. The specific calculation process for the main airflow inertial force flux value is as follows: ; in, Indicates the number of times after the current moment. Each sampling time, Starting from 1, Indicates the first The inertial flux value of the main airflow at each sampling time. This represents the inertial impact equivalent at the current moment. This indicates the sampling sequence number starting from the current moment. Indicating the first in the predicted decay trajectory The main airflow velocity value at each sampling time. Indicates the first The main airflow velocity value at the time preceding the sampling time. This represents the current velocity value of the main airflow. The meaning of this formula is: the equivalent inertial impact at the current moment is multiplied by the velocity decrease ratio at each sampling moment in sequence. The velocity decrease ratio is calculated as the ratio of the relative velocity decrease to the current velocity value. The cumulative multiplication method ensures that the inertial force flux value at each moment is affected by the cumulative velocity decrease of all previous moments, thus achieving a time-domain broadening effect on the impact.

[0035] When converting the momentum flux at the additive injection outlet to the inertial force flux of the main airflow point by point, the product of the injection pressure and the injection port area at the additive injection outlet is taken as the total injection momentum. The momentum flux at the injection outlet is obtained by dividing the total injection momentum by the cross-sectional area of ​​the injection port. The corresponding value at the same sampling time is taken from the sequence of inertial force flux values ​​of the main airflow. The momentum flux at the injection outlet is taken as the numerator and the inertial force flux of the main airflow is taken as the denominator. The ratio is calculated point by point to obtain the dimensionless comparison value at each sampling time. The dimensionless comparison values ​​at all sampling times are arranged in chronological order to form the dimensionless comparison value sequence.

[0036] Using the dynamic critical penetration threshold as the upper limit boundary and the lowest attenuation inflection point value in the predicted attenuation trajectory as the lower limit boundary, the allowable range of the dimensionless comparison value sequence is limited to the upper and lower limits to form a safe operating channel. The minimum value of the predicted attenuation trajectory in the entire prediction period is taken as the lowest attenuation inflection point value, and this lowest attenuation inflection point value is taken as the lower limit boundary. The dynamic critical penetration threshold is taken as the upper limit boundary, and the constraint condition is that each value in the dimensionless comparison value sequence must be greater than the lower limit boundary and less than the upper limit boundary. The area between the upper and lower limits constitutes the safe operating channel.

[0037] It should be noted that the derivation of the equivalent relationship between the dimensionless momentum ratio and the wall impact force is as follows: The equivalent relationship between the dimensionless ratio of the additive injection momentum to the inertial force of the main gas flow and the impact force borne by the furnace wall is established based on the stagnation pressure theory of a circular turbulent jet impacting an infinitely large plate.

[0038] Let the density of the additive jet at the nozzle be... The jet speed is The dynamic pressure of the jet satisfy: ; Let the density of the main gas flow at the furnace cross-section be... Flow velocity is Then the inertial flux of the main airflow satisfy: ; Define dimensionless momentum ratio for: ; According to the theory of turbulent jets, when a jet impacts a wall, the stagnant pressure at the center of the wall... With jet flow pressure and jet outlet diameter Injection distance (furnace diameter) The following relationship exists between them: ; in, The jet impact coefficient (determined by the jet angle) is the jet impact coefficient. This is a correction factor for high-temperature gas expansion and turbulent dissipation.

[0039] The structure of the carbon black reactor is fixed (i.e.) Under the conditions that the main airflow properties are constant (fixed injection angle) and the variation of the main airflow properties is controllable within a certain operating range, the wall stagnation pressure is... Ratio of dimensionless momentum The monotonically increasing relationship between them can be simplified as follows: ; in For about It is a monotonically increasing function.

[0040] Therefore, the maximum permissible momentum ratio As a control constraint throughout the entire process, from an engineering control perspective, it is equivalent to constraining the maximum wall stagnant pressure to the critical withstand pressure of the furnace lining material. Below, namely: ; This application uses the dimensionless ratio as the constraint boundary, which essentially simplifies the complex multiphase flow impact problem into a single-parameter threshold control problem under fixed boundary conditions. It is an engineering simplification method with physical basis in the field of high-temperature zone control of carbon black reactors.

[0041] The hydrodynamic coupling mechanism between velocity decay rate and wall pressure pulsation: The matching relationship between velocity decay rate and wall pressure fluctuation is derived from the momentum equation (Euler equation) for unsteady flow.

[0042] In the high-temperature zone of the furnace, neglecting body forces, the one-dimensional unsteady flow momentum equation along the main airflow direction is: ; Discretize the partial differential equation, and at two adjacent sampling times (sampling interval) Between ), the rate of velocity decay Defined as: ; Substituting into the discrete momentum equation, we obtain the pressure gradient at this wall location: ; At a fixed measuring point on the furnace wall, the instantaneous value of the pressure gradient can be directly mapped to the real-time pressure pulsation amplitude at that measuring point. Therefore, matching the real-time pressure pulsation value of the wall with the velocity decay rate is essentially using kinematic parameters (velocity change rate) to invert dynamic parameters (wall pressure load), which has clear support from fluid dynamics theory.

[0043] Analytical derivation of the time-domain broadening (cumulative recursive) model of inertial force flux: The inertial impact equivalent at the current moment is During the airflow deceleration process, the velocity decrease at each sampling moment causes dissipation of the airflow's impact energy on the wall. Let the... The relative decrease in velocity at time t is: ; The proportion of the impact energy dissipated at that moment to the total energy is proportional to... Based on this, a first-order linear difference recursive equation for the inertial force flux with respect to time is established: ; Expanding the recurrence relation, we obtain the analytical solution: ; Transform the difference equation into continuous-time form. When When the amount is small, Taking the logarithm, we get: ; Physical meaning: This exponential decay model indicates that as the main airflow velocity decreases from... Descending to The inertial force flux decays exponentially, which is consistent with the Kolmogorov turbulent dissipation physics law in high-temperature turbulent boundary layers, where energy is dissipated stepwise from large-scale eddies to small-scale eddies (energy level series). This application uses a cumulative multiplication form to characterize the time-domain broadening of the impact force, which has a sufficient theoretical basis in fluid mechanics.

[0044] Derivation of the first law of thermodynamics for theoretical temperature gradient mapping: The process of mapping the velocity decay rate to the theoretical temperature change rate is derived based on the boundary layer energy conservation equation.

[0045] In the high-temperature zone of the furnace, the frictional heat generation rate between the airflow and the wall is... The dissipation relationship of wall friction work is satisfied: ; in For wall shear stress, The velocity gradient is the normal velocity gradient of the wall.

[0046] Under simplified engineering conditions, wall shear stress Proportional to air pressure The wall normal velocity gradient is proportional to the mainstream velocity. When the airflow velocity decreases, the rate of velocity decrease is... The rate of temperature change caused by frictional heat generation is: ; in The coefficient of frictional heat generation of the wall surface in the high-temperature zone (dimension: ). The specific heat capacity of the gas at constant pressure is determined by the frictional properties of the wall material and the specific heat capacity of the gas at constant pressure, and is obtained through pre-calibration.

[0047] Further introduce high-temperature radiation weighting coefficient (Value range 0.6-0.8) After applying radiation attenuation correction to the frictional temperature rise, the final mapping formula for the theoretical temperature change rate is obtained: ; This derivation shows that the physical essence of using the velocity decay rate to predict the rate of temperature change is: converting the mechanical energy lost during the deceleration of the airflow into a thermodynamic temperature rise through frictional dissipation, and then mapping the energy after correction by radiative heat transfer, which is in complete accordance with the first law of thermodynamics.

[0048] Please see Figure 3 As shown, in S3, the predicted attenuation trajectory is imported into the safe operation channel. Based on the rate of change of the trajectory's position within the channel, the maximum permissible injection momentum limit that the additive can achieve at the current moment is derived in reverse. Specifically, this includes: When reading the position coordinates of the predicted attenuation trajectory within the safe operating channel at the current moment, the position coordinates are determined by the vertical axis value of the predicted attenuation trajectory at the current sampling moment. The vertical axis value represents the predicted value of the main airflow velocity at the current moment. Using this vertical axis value as the position coordinate value, the value corresponding to the current sampling moment is directly retrieved from the array storing the values ​​of the predicted attenuation trajectory at each moment.

[0049] When extracting the first distance relative to the upper boundary of the channel and the second distance relative to the lower boundary of the channel, the difference between the current position coordinate value and the current boundary value of the lower boundary of the safe operation channel is used as the second distance. Similarly, the difference between the current position coordinate value and the current position coordinate value is used as the first distance. The upper boundary value is the dynamic critical penetration threshold, and the lower boundary value is the lowest attenuation inflection point value in the predicted attenuation trajectory. Dividing the value of the first distance by the value of the second distance yields the position deviation ratio. A ratio greater than one indicates the trajectory is closer to the upper boundary, and a ratio less than one indicates the trajectory is closer to the lower boundary.

[0050] When obtaining the amplitude limiting reduction coefficient by dividing the position deviation ratio by the current position change rate, the current position change rate is taken as the slope value of the predicted attenuation trajectory at the current moment. This slope value is obtained by subtracting the position coordinate value of the previous sampling moment from the current position coordinate value and then dividing by the sampling interval of 200 milliseconds. The quotient obtained by dividing the position deviation ratio by the absolute value of the position change rate is used as the amplitude limiting reduction coefficient. When the position change rate approaches zero, the amplitude limiting reduction coefficient is taken as the value of the previous period.

[0051] The amplitude reduction factor is multiplied by the allowable injection momentum value at the previous moment, and the product is used as the initial amplitude limit value at the current moment. The allowable injection momentum value at the previous moment is stored in the historical value register of the controller. At the initial operation moment, the rated injection momentum value of the additive metering pump is taken as the initial value.

[0052] When performing weighted smoothing of the initial limit value and the limit value at the previous moment, a weighting coefficient of 0.7 is applied to the initial limit value, and a weighting coefficient of 0.3 is applied to the limit value at the previous moment. The two weighted results are added together, and the sum is taken as the maximum allowable jet momentum limit value at the current moment.

[0053] In S4, the maximum permissible injection momentum limit is converted into a gradual depressurization curve. The additive injection velocity is controlled to gradually decrease along the gradual depressurization curve to below the limit. When the predicted main airflow velocity is detected to rise back to the set percentage, the injection momentum limit is released in a timing sequence that lags behind the start of the rise. Specifically, this includes: The total pressure reduction duration is set based on the mechanical inertia duration of the damper actuator. A mechanical inertia duration of 6 seconds is taken as the total pressure reduction duration. The control cycle is set to 200 milliseconds. Dividing the total pressure reduction duration of 6 seconds by the control cycle of 200 milliseconds yields 30 control cycles. The maximum permissible injection momentum limit is divided into 30 equal parts, and one limit is allocated to each control cycle. The allocation value is the quotient obtained by dividing the maximum permissible injection momentum limit by 30. The initial momentum setpoint is the rated injection momentum value of the additive metering pump under stable operating conditions. This rated value is determined by the pump's factory calibration parameters and is set to 2.5 kilowatts.

[0054] Subtract the allocated value from the initial momentum setpoint for each control cycle. The difference for the first control cycle equals the initial momentum setpoint minus the allocated value for the first control cycle; the difference for the second control cycle equals the initial momentum setpoint minus the sum of the allocated values ​​for the previous two control cycles, and so on, until the difference for the 30th control cycle equals the initial momentum setpoint minus the sum of the allocated values ​​for all 30 control cycles, which equals 0. Arrange the differences of each control cycle sequentially in chronological order, with time on the horizontal axis and the difference value on the vertical axis. Connect the difference points of adjacent control cycles with straight line segments to form a stepped broken line that gradually decreases from the initial momentum setpoint to 0. This stepped broken line serves as the gradual depressurization curve.

[0055] When the pressure reduction is driven by the deviation between the current injection speed of the additive and the limit value at the corresponding moment in the pressure reduction curve, the current injection speed of the additive is obtained in real time by the turbine flow meter installed on the additive injection pipeline. The flow meter outputs a volumetric flow rate value every two hundred milliseconds. The current injection speed value is obtained by dividing the volumetric flow rate value by the cross-sectional area of ​​the injection port.

[0056] Within each control cycle, the vertical axis value corresponding to the start time of that control cycle is read from the deceleration and pressure reduction curve, and this value is used as the current limit value. The current injection speed value is subtracted from this limit value, and the difference is taken as the speed deviation. The speed deviation is divided by the current injection speed value, and the quotient is taken as the deviation ratio.

[0057] When the deviation ratio is positive, meaning the current injection speed is greater than the current limit value, the deviation ratio is multiplied by the preset maximum reduction base value, and the product is used as the pressure reduction step size for the current control cycle. The maximum reduction base value is 5% of the current injection speed value. This value is determined based on the minimum frequency adjustment step size of the additive metering pump inverter, that is, the proportion of the injection speed change caused by each step adjustment of the inverter to the current speed value.

[0058] The difference between the current injection speed and the pressure reduction step is used as the speed setpoint for the next control cycle. This speed setpoint is converted into an analog signal and output to the frequency converter of the additive metering pump. The frequency converter adjusts the pump speed according to this speed setpoint, so that the injection speed gradually decreases according to the pressure reduction step within each control cycle. At the end of each control cycle, the current injection speed value is updated to the speed setpoint, and the deviation calculation for the next control cycle is performed, so that the actual injection speed decreases according to a stepped broken line cycle by cycle.

[0059] When the predicted main airflow velocity is detected to rise to a set percentage for three consecutive sampling cycles, the sampling cycle and control cycle are both set to 200 milliseconds. The set percentage is defined as 80% of the velocity rise value in the current predicted decay trajectory reaching the velocity descent initiation point. Within each sampling cycle, the current predicted main airflow velocity is compared with the velocity descent initiation point value, which is the main airflow velocity value corresponding to the moment the predicted decay trajectory begins to decline. When the current predicted value is greater than or equal to 80% of the velocity descent initiation point value for three consecutive sampling cycles, the rise is confirmed as valid, and the start time of the first sampling cycle that meets this condition is taken as the rise initiation time.

[0060] The timing is set to zero at the start of the recovery. The preset lag time is one-third of the damper's mechanical inertia time, which is two seconds. Timing starts from the start of the recovery and the current limit value remains unchanged until the timing value reaches two seconds. When the timing value reaches two seconds, the proportion of the pressure reduction process that has been executed in the total pressure reduction time of 6 seconds is taken, which is the proportion obtained by dividing the number of executed control cycles by 30. This proportion is used to determine the ratio of the remaining limit value to the initial limit value. The limit value corresponding to the remaining proportion is divided equally according to the number of remaining control cycles, and one part is released in each control cycle until the limit value is restored to the initial momentum setting value.

[0061] During the release process, the amplitude limit value after release in each control cycle is compared with the step value corresponding to the same moment in the slow descent and depressurization curve, and the larger of the two values ​​is taken as the actual amplitude limit output value of that control cycle.

[0062] In S5, the rate of change of the temperature field gradient at the furnace outlet is collected and compared with the theoretical temperature gradient corresponding to the predicted attenuation trajectory. When the comparison deviation exceeds the allowable range, the critical penetration threshold is dynamically relaxed, and the boundary of the safe operation channel is corrected with the relaxed threshold. The final constraint command is then output, specifically including: When continuously collecting temperature values ​​from multiple circumferentially distributed temperature measurement points at the furnace outlet, eight thermocouples are embedded at equal intervals along the circumference at the furnace outlet cross-section. The measuring end of each thermocouple extends into the airflow channel at the furnace outlet, and each thermocouple outputs a temperature measurement value every 200 milliseconds. The instantaneous rate of change of the temperature at the same measurement point is obtained by subtracting the temperature at the previous sampling time from the temperature at the current sampling time, and dividing the difference by the sampling interval of 200 milliseconds. This instantaneous rate of change characterizes how quickly the temperature at the measurement point changes over time.

[0063] The instantaneous rate of change of the eight temperature measurement points is arranged in a clockwise circumferential order to generate a temperature field gradient rate of change sequence consisting of eight values.

[0064] When mapping the main airflow velocity values ​​at each moment in the predicted decay trajectory to the theoretical temperature change rate, the current moment's main airflow velocity value is subtracted from the previous moment's main airflow velocity value in the predicted decay trajectory; the difference is taken as the velocity decrease amplitude. A negative velocity decrease amplitude indicates a decrease in velocity, while a positive value indicates a recovery in velocity. The velocity decrease amplitude is divided by the sampling interval of 200 milliseconds to obtain the velocity decay rate. The velocity decay rate is multiplied by the preset high-temperature zone wall friction heat generation coefficient, which is taken as the temperature rise corresponding to a velocity decrease of 0.15 degrees Celsius per meter per second. This coefficient is pre-calibrated based on the frictional characteristics of the furnace high-temperature zone wall material and the specific heat capacity of the gas components. The product is taken as the instantaneous frictional temperature rise equivalent.

[0065] The instantaneous frictional temperature rise equivalent is superimposed onto the temperature change rate baseline value from the previous sampling moment. This baseline value is the theoretical temperature change rate calculated at the previous sampling moment, and is set to 0 at the first sampling moment. The superposition result is multiplied by a high-temperature radiation weighting coefficient. This coefficient is determined based on the ratio of the radiation intensity measured by the furnace outlet radiation pyrometer to the theoretical radiation intensity, and its value ranges from 0.6 to 0.8. The real-time value of this coefficient is obtained by dividing the current radiation intensity by the theoretical radiation intensity corresponding to the current temperature. The product is used as the theoretical temperature change rate corresponding to the current moment.

[0066] Perform the above calculations sequentially for each sampling moment, arrange the theoretical temperature change rates of all moments by time, and generate a theoretical temperature gradient mapping sequence with the same number of sampling points as the predicted decay trajectory.

[0067] When subtracting the corresponding values ​​in the theoretical temperature change rate and temperature field gradient change rate sequences point by point, the value at the current sampling moment in the theoretical temperature gradient mapping sequence is taken from the value at the same sampling moment in the temperature field gradient change rate sequence. The theoretical value is subtracted from the measured value, and the difference is taken as the deviation value at that moment. This subtraction operation is performed for all sampling moments, and the deviation values ​​at each moment are arranged in chronological order to obtain the deviation sequence.

[0068] When converting consecutive deviations exceeding the allowable range in the cumulative deviation sequence into relaxation increments, the allowable range is set to the interval from -0.5 degrees Celsius per second to +0.5 degrees Celsius per second. Deviations exceeding this range are considered excessive. Starting from the beginning of the deviation sequence, the duration of consecutive excessive deviations is accumulated. The accumulated excessive duration is multiplied by the corresponding relaxation coefficient per second, with the relaxation coefficient set to 0.01 MPa per second. The product is used as the relaxation increment. For every second increase in the accumulated excessive duration, the relaxation increment increases by 0.01 MPa.

[0069] When using the relaxation increment to superimpose the critical penetration threshold as the relaxed threshold, the current dynamic critical penetration threshold plus the relaxation increment is added, and the result is used as the relaxed threshold. The upper boundary of the safe operation channel is replaced with the relaxed threshold, while the original lower boundary remains unchanged. The replaced upper boundary and the original lower boundary together limit the output range of the final constraint command, that is, the final constraint command is limited to the interval greater than or equal to the lower boundary value and less than or equal to the relaxed upper boundary value.

[0070] The working principle of this invention is as follows: By collecting the current damper opening change rate and the flue gas density in the high-temperature zone, the opening change rate is broadened based on the damper's mechanical inertia duration and superimposed with the density compensation value to generate a predicted attenuation trajectory of the main airflow velocity over a future period. A critical penetration threshold is dynamically set based on the furnace lining's cumulative thermal shock data, and the dimensionless comparison value between the additive injection momentum and the main airflow inertial force is used as a control constraint throughout the process. A safe operating channel is constructed with the critical penetration threshold as the upper boundary. The predicted attenuation trajectory is imported into the safe operating channel, and the maximum allowable additive injection at the current moment is deduced in reverse based on the trajectory's position change rate within the channel. Momentum limit value; the maximum allowable injection momentum limit value is converted into a gradual depressurization curve, and the additive injection speed is controlled to gradually decrease along the gradual depressurization curve to below the limit value. When the main gas flow velocity is detected to rise back to the set proportion, the injection momentum limit value is released in a time sequence that lags behind the start point of the rise. The gradient change rate of the furnace outlet temperature field is collected and compared with the theoretical temperature gradient corresponding to the predicted attenuation trajectory. When the comparison deviation exceeds the allowable range, the critical penetration threshold is dynamically relaxed. The relaxed threshold is used to correct the boundary of the safe operation channel and output the final constraint command to achieve full-time constraint control of the additive injection amount.

[0071] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor, characterized in that, Includes the following steps: S1: Collect the current damper opening change rate and the flue gas density in the high-temperature zone. Based on the damper mechanical inertia duration, superimpose the opening change rate and the density compensation value to generate the predicted attenuation trajectory of the main airflow velocity in the future period. S2: Based on the cumulative thermal shock data of the furnace lining, the critical penetration threshold is dynamically set. The dimensionless comparison value sequence obtained by converting the point-by-point ratio of the momentum flux at the additive injection outlet to the inertial force flux of the main gas flow is used as the whole process control constraint. The dynamic critical penetration threshold is used as the upper limit boundary, and the lowest attenuation inflection point in the predicted attenuation trajectory is used as the lower limit boundary. The allowable range of the dimensionless comparison value sequence is limited to the upper limit boundary and the lower limit boundary, thus constructing a safe operation channel. S3: Import the predicted attenuation trajectory into the safe operation channel, read the position coordinates of the predicted attenuation trajectory at the current moment, extract the ratio of the position coordinates relative to the upper boundary of the channel to the first distance and the second distance relative to the lower boundary of the channel as the position deviation ratio, divide the position deviation ratio by the position change rate at the current moment to obtain the limit reduction coefficient, multiply the limit reduction coefficient by the allowable jet momentum value at the previous moment to obtain the initial limit value at the current moment, and after weighted smoothing the initial limit value and the limit value at the previous moment, use it as the maximum allowable jet momentum limit value at the current moment; S4: Convert the maximum allowable injection momentum limit value into a gradual depressurization curve, control the additive injection speed to gradually decrease along the gradual depressurization curve to below the limit value, and release the injection momentum limit value in a timing sequence that lags behind the start point of the rise when the main airflow speed is detected to rise back to the set percentage. S5: Collect temperature values ​​from multiple temperature measurement points distributed circumferentially at the furnace outlet. Divide the change in temperature value at each measurement point relative to the previous sampling time by the sampling interval to obtain the instantaneous rate of change. Arrange all instantaneous rates of change circumferentially to generate a temperature field gradient rate of change sequence. Map the main airflow velocity value corresponding to each moment in the predicted attenuation trajectory to the theoretical temperature rate of change to generate a theoretical temperature rate of change sequence. Subtract each instantaneous rate of change in the temperature field gradient rate of change sequence at the same sampling time from the theoretical temperature rate of change at the corresponding moment in the theoretical temperature rate of change sequence to obtain a deviation sequence. When there are consecutive deviation values ​​exceeding the allowable range in the deviation sequence, dynamically relax the critical penetration threshold, correct the safe operation channel boundary with the relaxed threshold, and output the final constraint command.

2. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 1, characterized in that, The process of generating the predicted decay trajectory is as follows: After collecting the damper opening change rate and the flue gas density in the high-temperature zone, the opening change rate is broadened on the time axis according to the damper mechanical inertia duration to generate a time-based displacement sequence that reflects the damper action lag. The flue gas density is converted into the hot friction coefficient of the flow channel wall, and the density compensation value is weighted and corrected using the hot friction coefficient to obtain the hot drag correction coefficient. The time point of each time point in the time base displacement sequence is coupled point by point with the thermal drag correction coefficient on the time axis. The coupling result is used as the attenuation inflection point value of the main airflow velocity at each sampling time in the subsequent time period. The predicted attenuation trajectory is formed by connecting the attenuation inflection point values ​​in sequence.

3. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 1, characterized in that, The process of forming the safe operation channel is as follows: The temperature fluctuation amplitude and high temperature holding time of the furnace lining wall are collected. The temperature fluctuation amplitude is weighted by the high temperature holding time to generate the erosion resistance degradation coefficient. The product of the initial tolerance limit and the erosion resistance degradation coefficient is set as the dynamic critical penetration threshold. The inertial force flux of the main airflow at each moment is extracted based on the predicted attenuation trajectory. The momentum flux at the additive injection outlet is converted to the inertial force flux of the main airflow point by point to obtain a dimensionless comparison value sequence. Using the dynamic critical penetration threshold as the upper limit boundary and the lowest attenuation inflection point in the predicted attenuation trajectory as the lower limit boundary, the allowable range of the dimensionless comparison value sequence is limited to the upper and lower limits, forming a safe operating channel.

4. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 3, characterized in that, The inertial flux of the main airflow at each moment is extracted based on the predicted attenuation trajectory, specifically including: The velocity decay rate at the current sampling moment is extracted from the predicted decay trajectory, and the velocity decay rate is matched with the real-time pressure pulsation value of the furnace wall. The pressure pulsation values ​​are accumulated according to the sampling period to obtain the cumulative wall impact. The cumulative wall impact is corrected by the velocity decay rate to eliminate inertial hysteresis error and obtain the inertial impact equivalent at the current moment. The inertial impact equivalent is time-domain broadened according to the velocity decrease ratio at each moment in the predicted decay trajectory, and the broadened inertial impact equivalent is used as the inertial force flux value of the main airflow at each moment.

5. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 1, characterized in that, The release of the jet momentum limit value with a timing lag behind the recovery start point specifically includes: The maximum permissible injection momentum limit is proportionally distributed to each control cycle according to the total depressurization time. The difference between the distributed value of each control cycle and the initial momentum setpoint is used to generate a step-decreasing curve. The pressure reduction is driven by the deviation between the current injection speed of the additive and the limit value at the corresponding moment in the pressure reduction curve, so that the injection speed decreases in a step-like manner cycle by cycle. When the predicted value of the main airflow velocity is detected to rise to the set percentage for three consecutive sampling cycles, the timing zero point is set at the start time of the rise, and after a preset lag time, the limiting value is released step by step according to the remaining percentage of the depressurization process.

6. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 5, characterized in that, The drive buck execution specifically includes: The difference between the current injection speed of the additive and the limit value at the corresponding moment of the current control cycle in the slow-deceleration and pressure reduction curve is taken as the speed deviation. The speed deviation is divided by the current injection speed to obtain the deviation ratio. When the deviation ratio is positive, the current cycle's voltage reduction step size is generated by multiplying the deviation ratio by the preset maximum reduction base value. Subtract the depressurization step from the current injection speed value to obtain the speed setpoint for the next control cycle; The speed setpoint is used as the execution command output, so that the injection speed approaches the stepped broken line with the pressure reduction step in each control cycle.

7. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 1, characterized in that, The output final constraint instruction specifically includes: The cumulative deviation values ​​that continuously exceed the allowable range in the cumulative deviation sequence are converted into relaxation increments based on the cumulative amount. The threshold threshold after relaxation is then superimposed on the critical penetration threshold. The upper boundary of the safe operation channel is replaced with the relaxed threshold, and the output range of the final constraint command is defined by the replaced upper boundary and the original lower boundary.

8. The method for synergistic control of turbulence intensity and additive injection in the high-temperature zone of a carbon black reactor according to claim 7, characterized in that, The process of mapping the main airflow velocity values ​​at each moment in the predicted attenuation trajectory to the theoretical temperature change rate specifically includes: The velocity decrease is obtained by subtracting the current velocity value from the previous velocity value in the predicted decay trajectory, and the velocity decay rate is obtained by dividing the velocity decrease by the time interval between the two samplings. The instantaneous frictional temperature rise equivalent is obtained by multiplying the velocity decay rate by the preset high-temperature zone wall friction heat generation coefficient. The instantaneous frictional temperature rise equivalent is superimposed onto the temperature change rate base value of the previous moment, and the superposition result is corrected by the high temperature radiation weighting coefficient and used as the theoretical temperature change rate corresponding to the current moment. By arranging the theoretical temperature change rate at all times in a time series, a theoretical temperature change rate sequence of the same length as the predicted decay trajectory is generated.

Images