Intelligent adaptive control method and system for gasoline hydrogenation device

Abstract

The present application belongs to the field of petrochemical automation technology, and relates to an intelligent adaptive control method and system for a gasoline hydrogenation device. The present application synchronously corrects the fuel valve, cold hydrogen valve and compressor speed reference by calculating the catalyst activity index; when adjusting the cold hydrogen valve or fuel valve to control the bed temperature, the speed and downstream cold hydrogen valve are corrected in linkage; when adjusting the speed to control the inlet pressure, each bed cold hydrogen valve is corrected in reverse, and the activity index is updated according to the deviation between the actual value and the reference. The problems of response lag and compensation mismatch caused by not adjusting according to the activity decay dynamic, the mutual coupling of temperature and pressure loops, the new deviation induced by the execution mechanism restraint and the frequent manual intervention are solved. The control target is adaptively adjusted with the activity change, the temperature and pressure are decoupled and adjusted, the execution mechanism coordination compensation mechanism is established, thereby the product quality fluctuation and energy consumption are reduced, the intervention frequency is reduced, and the mutual disturbance of multiple loops is avoided.

Description

Technical Field

[0001] This invention belongs to the field of petrochemical automation technology, and relates to an intelligent adaptive control method and system for a gasoline hydrogenation unit. Background Technology

[0002] Gasoline hydrotreating units are key process units in the oil refining industry for upgrading oil product quality, and their operational stability directly affects product quality and unit energy consumption. The hydrotreating reaction process exhibits nonlinear, time-varying, and multivariate coupling characteristics. Fluctuations in feedstock properties, changes in catalyst activity, and adjustments to operating conditions all interact to influence reaction temperature and system pressure.

[0003] Existing control schemes are typically based on PID strategies, treating reaction temperature and system pressure as independent controlled variables, and designing separate single-loop or cascade control systems. However, in actual operation, changing a certain controlled variable to adjust the reaction temperature often causes fluctuations in system pressure; conversely, adjusting the compressor's operating state to stabilize system pressure may alter the circulating hydrogen flow rate and cold hydrogen supply, thereby interfering with the temperature distribution of each reaction bed. This coupling relationship between the control loops causes the adjustment behaviors to influence each other, resulting in a low utilization rate of the control system and requiring frequent manual intervention from operators.

[0004] Catalyst activity gradually declines over time, significantly impacting the intensity of heat release and temperature distribution. Existing control methods typically set operating conditions to fixed values, failing to dynamically adjust control targets based on activity changes. When catalyst activity decreases, operators must manually adjust reaction temperature or other process parameters to compensate for the activity loss. This adjustment method suffers from lag and struggles to ensure a precise match between the compensation amount and the degree of activity change, potentially leading to product quality fluctuations or increased energy consumption.

[0005] Reaction temperature is typically controlled by adjusting the amount of cold hydrogen injected or the fuel supply, while system pressure is maintained by changing the compressor's operating status. These two control methods are interdependent in practice: changes in the amount of cold hydrogen affect the total system pressure and the composition of the circulating hydrogen, while changes in compressor operating conditions alter the cold hydrogen delivery capacity, thus causing temperature disturbances. Existing control architectures lack a coordinated compensation mechanism for this coupling effect; regulation in one loop often induces new deviations in another. Summary of the Invention

[0006] In view of this, in order to solve the problems mentioned in the background art, a smart adaptive control method and system for gasoline hydrogenation devices is proposed.

[0007] The first aspect of the present invention proposes an intelligent adaptive control method for a gasoline hydrogenation unit, comprising: collecting catalyst bed temperature, reactor inlet pressure and hydrogen concentration difference, and calculating catalyst activity index based on hydrogen concentration difference and bed temperature rise.

[0008] The control reference for the fuel valve, cold hydrogen valve and compressor speed is simultaneously corrected using the catalyst activity index.

[0009] With catalyst bed temperature as the controlled variable and cold hydrogen valve and fuel valve as actuators, the opening of cold hydrogen valve or fuel valve is adjusted when the catalyst bed temperature deviates from the bed temperature control reference. When the opening of cold hydrogen valve changes, the compressor speed is corrected. When the opening of fuel valve changes, the opening of downstream cold hydrogen valve is adjusted by feedforward.

[0010] The reactor inlet pressure is used as the controlled variable, and the compressor speed is used as the actuator. When the reactor inlet pressure deviates from the inlet pressure control reference, the compressor speed is adjusted. When the compressor speed changes, the opening degree of the cold hydrogen valve of each bed is corrected in the opposite direction.

[0011] Collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. Compare the control benchmark with the actual valve opening, actual speed, and actual measured values ​​to update the catalyst activity index.

[0012] A second aspect of the present invention provides an intelligent adaptive control system for a gasoline hydrogenation unit, comprising: a data acquisition and activity calculation module, used to acquire catalyst bed temperature, reactor inlet pressure and hydrogen concentration difference, and calculate catalyst activity index based on hydrogen concentration difference and bed temperature rise.

[0013] The reference correction module is used to synchronously correct the control references for the fuel valve, cold hydrogen valve, and compressor speed based on the catalyst activity index.

[0014] The temperature control module is used to adjust the opening of the cold hydrogen valve or the fuel valve when the catalyst bed temperature deviates from the bed temperature control reference, and to correct the compressor speed when the opening of the cold hydrogen valve changes, and to feedforward adjust the opening of the downstream cold hydrogen valve when the opening of the fuel valve changes.

[0015] The pressure control module is used to adjust the compressor speed when the reactor inlet pressure deviates from the inlet pressure control reference, and to reverse the opening degree of the cold hydrogen valves in each bed when the compressor speed changes.

[0016] The activity update module is used to collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. It compares the control benchmark with the actual valve opening, actual speed, and actual measured values ​​to update the catalyst activity index.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention obtains the catalyst activity index by collecting the hydrogen concentration difference and bed temperature rise, and uses the catalyst activity index to synchronously correct the control benchmark of the fuel valve, cold hydrogen valve and compressor speed. This solves the problem that the existing control method sets the operating conditions to a fixed value and does not dynamically adjust the control target according to the catalyst activity decline, resulting in a delayed compensation response and difficulty in matching the compensation amount. This enables the control target to be adaptively adjusted with the activity change, reducing product quality fluctuations and energy consumption increases.

[0018] (2) This invention solves the problem that existing strategies treat reaction temperature and system pressure as independent controlled variables, which leads to mutual influence between loops and the need for frequent manual intervention. It achieves decoupled regulation between temperature and pressure control loops and reduces the frequency of manual intervention.

[0019] (3) This invention corrects the compressor speed when the opening of the cold hydrogen valve changes and feeds forward to adjust the opening of the downstream cold hydrogen valve when the opening of the fuel valve changes. This solves the problem that the reaction temperature and system pressure regulation means are mutually constrained and the existing control architecture lacks a coordination and compensation mechanism for this coupling effect, which leads to the regulation behavior of one loop inducing new deviations in another loop. It establishes a coordination and compensation mechanism between actuators and avoids mutual disturbances in the regulation process of multiple control loops. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of an intelligent adaptive control method for a gasoline hydrogenation device according to the present invention;

[0022] Figure 2 This is the closed-loop logic diagram of adaptive tracking and benchmark correction of catalyst activity decay in this invention;

[0023] Figure 3This is a timing diagram comparing the control effects under disturbance conditions in this invention;

[0024] Figure 4 This is a schematic diagram showing the connection of each module in the intelligent adaptive control system of a gasoline hydrogenation device according to the present invention. Detailed Implementation

[0025] 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.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0027] The following description, in conjunction with the accompanying drawings, details the specific scheme of the intelligent adaptive control method and system for a gasoline hydrogenation device provided by the present invention.

[0028] Example 1

[0029] Please see Figure 1 As shown, this invention proposes an intelligent adaptive control method for a gasoline hydrogenation unit, including steps S1 to S5: The gasoline hydrogenation unit encompasses processes such as feedstock heating, multi-bed catalytic reaction, and circulating hydrogen compression, with each variable exhibiting strong coupling characteristics: adjusting the cold hydrogen valve or fuel valve to control the temperature inevitably changes the gas flow rate and induces inlet pressure fluctuations; conversely, adjusting the compressor to stabilize the pressure will reshape the cold hydrogen distribution and reversely interfere with the temperature field. This mutual constraint among multiple actuators, coupled with the exothermic reference drift caused by catalyst activity decay during long-term operation, makes traditional fixed setpoint control highly susceptible to oscillation.

[0030] To address the issues of control benchmark drift, pressure fluctuations, and temperature runaway caused by a lack of coordinated actuator linkage due to activity decay, this invention constructs an activity index calculation model centered on hydrogen concentration difference and bed temperature rise, using their dynamic changes as the basis for synchronous correction of control benchmarks for three types of actuators. Based on this, a dual-loop system for temperature and pressure is established with a coupling and coordination mechanism, enabling changes in the cold hydrogen valve to correlate with compressor speed, changes in the fuel valve to feedforward and adjust the downstream cold hydrogen valve, and changes in compressor speed to reverse and correct the cold hydrogen valve. Furthermore, by collecting the comprehensive deviation between the actual state and the benchmark, the activity index is updated in a closed loop, forming a complete closed loop of evaluation, correction, coordination, and re-evaluation, maintaining control accuracy throughout the entire lifecycle and mitigating the risk of runaway.

[0031] S1. Collect catalyst bed temperature, reactor inlet pressure and hydrogen concentration difference, and calculate catalyst activity index based on hydrogen concentration difference and bed temperature rise.

[0032] In the long-term operation of gasoline hydrotreating units, catalyst surface carbonization deactivation is a rigid engineering constraint restricting stable production. Adhering to a fixed temperature setpoint leads to a decline in catalyst reactivity, making it easy for fuel quality to deviate from control targets; while manual delayed temperature compensation often triggers bed overheating risks. Conventional monitoring methods only provide instantaneous absolute values ​​of current process parameters and cannot proactively identify the decline in system responsiveness caused by activity degradation. Therefore, this step, based on the inherent correlation between hydrogen consumption and bed temperature rise during the reaction process, constructs a real-time calculation strategy for the catalyst activity index using online measurable concentration and temperature signals, providing a quantitative input basis for subsequent adaptive correction of the control baseline.

[0033] Specifically, the inlet and outlet temperatures of each catalyst bed are first collected using thermocouples installed at the inlet and outlet ends. The inlet and outlet hydrogen concentrations are collected using online hydrogen analyzers installed on the reactor inlet and outlet pipelines. The inlet pressure is collected using a pressure transmitter installed on the reactor inlet pipeline. The signals from each measuring point are collected at a uniform time, with the data refresh cycle of the online hydrogen analyzer as the standard. The controller reads these signals synchronously and caches them in the data storage unit. The reactor inlet pressure is used as the controlled variable in the subsequent pressure control loop, while the bed temperature and hydrogen concentration are used to calculate the catalyst activity index in this step.

[0034] Subsequently, the hydrogen concentration difference is obtained by subtracting the hydrogen concentration at the reactor outlet from the hydrogen concentration at the reactor inlet. This hydrogen concentration difference characterizes the amount of hydrogen consumed in the hydrogenation reaction. The difference between the outlet temperature and the inlet temperature of each catalyst bed is calculated for each bed, and the maximum value is taken as the bed temperature rise. The thermal effect of the bed with the most intense heat release characterizes the overall reaction intensity of the device. The hydrogen concentration difference and the bed temperature rise obtained thus constitute two state variables for calculating the catalyst activity index.

[0035] Based on this, the bed temperature rise is compared with a temperature threshold, which is three times the sum of the absolute values ​​of the maximum allowable errors of the temperature measuring elements at the bed inlet and outlet. This ensures that when the bed temperature rise exceeds this threshold, the measurement error accounts for no more than one-third of the temperature rise signal. When the bed temperature rise exceeds this threshold, it indicates that the temperature rise signal is higher than the measurement error level, and the hydrogen exothermic reaction in the bed is actually proceeding. The ratio of the hydrogen concentration difference to the bed temperature rise is calculated to obtain the hydrogen consumption temperature rise ratio, which represents the amount of hydrogen consumed per unit bed temperature rise. When the bed temperature rise is less than or equal to this threshold, it indicates that the bed exothermic reaction is weak, and the temperature rise signal and the measurement error are on the same order of magnitude and cannot be distinguished. Performing the ratio calculation will amplify the measurement error and cause the activity index to be distorted. Therefore, the catalyst activity index at the previous moment is used as the current catalyst activity index.

[0036] Furthermore, the sign of the hydrogen consumption-temperature rise ratio is determined: when the hydrogen consumption-temperature rise ratio is greater than zero and the bed temperature rise is greater than the temperature threshold, it indicates that the hydrogen concentration at the reactor outlet is lower than the hydrogen concentration at the inlet, hydrogen is being truly consumed, and the temperature rise signal is reliable. Hydrogen consumption and bed temperature rise synchronously reflect the catalytic reaction intensity. The relative hydrogen concentration difference is obtained by dividing the hydrogen concentration difference by the initial hydrogen concentration difference, and the relative bed temperature rise is obtained by dividing the bed temperature rise by the initial bed temperature rise. Here, the initial hydrogen concentration difference and the initial bed temperature rise are both taken as the arithmetic mean of the corresponding quantities in each collection cycle during the full-load calibration period of the device. After this normalization process, the sum of the terms are all dimensionless quantities. Subsequently, the catalyst activity index is calculated according to the following formula. : .

[0037] in, Due to the hydrogen concentration difference, For bed temperature rise, The initial hydrogen concentration difference, This represents the initial bed temperature rise.

[0038] When the hydrogen consumption temperature rise ratio is less than or equal to zero and the bed temperature rise is greater than the temperature threshold, it indicates that the hydrogen concentration at the reactor outlet is not lower than the hydrogen concentration at the inlet, which contradicts the objective law that the hydrogenation reaction continuously consumes hydrogen. It is determined that the online hydrogen analyzer has a measurement abnormality, and the catalyst activity index at the previous moment is used as the current catalyst activity index, and a hydrogen concentration measurement abnormality alarm signal is sent to the controller.

[0039] The catalyst activity index is a dimensionless quantity, characterized by the average of hydrogen consumption intensity and bed heat release intensity, representing the catalyst's current macroscopic ability to promote the hydrogenation reaction. The relative hydrogen concentration difference reflects the change in hydrogen consumption relative to the initial state, and the relative bed temperature rise reflects the change in bed heat release intensity relative to the initial state. The stronger the catalyst's macroscopic reactivity, the greater the hydrogen consumption and bed temperature rise, and the higher the overall catalyst activity index. With prolonged operation, catalyst deactivation due to carbon buildup leads to a decrease in hydrogen consumption and bed temperature rise, and the catalyst activity index generally shows a decreasing trend.

[0040] The catalyst activity index is stored in the data storage unit, serving as the basis for the continued calculation of the activity index at the next acquisition time and as the quantitative input for subsequent correction of the fuel valve, cold hydrogen valve, and compressor speed control reference. Under the full-load calibration condition of the unit, the arithmetic mean of the catalyst activity index calculated in each acquisition cycle during the calibration period is used as the initial catalyst activity index.

[0041] S2. The control reference for the speed of fuel valve, cold hydrogen valve and compressor is simultaneously corrected by the catalyst activity index.

[0042] During long-term operation of a gasoline hydrogenation unit, the catalyst's reactivity continuously declines. If the initial actuator settings remain unchanged, the system will passively fall into frequent over-limit adjustments to maintain the target temperature, easily leading to fluctuations in localized heat points within the bed. Conventional control can only passively compensate along a fixed baseline after deviations occur, making it difficult to overcome the dynamic response lag caused by activity decline. Therefore, this step uses the catalyst activity index as a leading driving force to simultaneously correct the control baselines for the fuel valve, cold hydrogen valve, and compressor speed. This allows the set trajectory to actively offset with changes in reactivity, eliminating the regulation oscillations induced by baseline mismatch at the source.

[0043] Specifically, the catalyst activity index at the current acquisition time and the previous acquisition time are read from the data storage unit, and the difference between the two is taken as the activity change. This activity change represents the direction and magnitude of the change in catalyst reaction capacity between adjacent acquisition cycles.

[0044] The product of the absolute value of the change in activity and the corresponding actuator gain coefficient is used as the baseline change of the actuator. The gain coefficient is obtained as follows: During the full-load calibration period, the catalyst activity index and the actual readings of the fuel valve opening, cold hydrogen valve opening, and compressor speed required to maintain the product sulfur content at each sampling time are recorded. A univariate linear regression is performed with the catalyst activity index as the independent variable and the actual readings of the three actuators during stable operation as the dependent variable. The absolute values ​​of the slopes of the three fitted lines are used as the fuel valve opening gain coefficient, cold hydrogen valve opening gain coefficient, and compressor speed gain coefficient, respectively. This gain coefficient represents the adjustment amount of the corresponding actuator required for each unit change in the catalyst activity index. The initial values ​​of the fuel valve control baseline, cold hydrogen valve control baseline, and compressor speed control baseline are taken as the actual readings of the fuel valve opening, cold hydrogen valve opening, and compressor speed during stable operation recorded during the full-load calibration period.

[0045] Since the catalyst activity index can change in three ways between adjacent collection cycles—rising, falling, or remaining flat—and the corresponding exothermic reaction intensity and hydrogen consumption change in opposite directions, the required actuator baseline correction directions are also opposite. Therefore, corrections are performed in three ways based on the sign of the activity change: When the activity change is greater than zero, it indicates that the catalyst's reactivity is enhanced, the bed hydrogenation exotherm is intensified, and the hydrogen consumption is increased. If the original baseline is maintained, the bed temperature will surge and the circulating hydrogen partial pressure will decrease. Therefore, the fuel valve control baseline is reduced by its baseline change to obtain the new fuel valve control baseline, in order to reduce the reactor inlet material temperature and offset the heat release increment; the cold hydrogen valve control baseline is increased by its baseline change to obtain the new cold hydrogen valve control baseline, in order to increase the cold hydrogen quantity to dilute and remove excess heat from the bed; the compressor speed control baseline is increased by its baseline change to obtain the new compressor speed control baseline, in order to increase the circulating hydrogen flow rate, compensate for the hydrogen consumption increment caused by the enhanced activity, and maintain the hydrogen-to-oil ratio.

[0046] When the change in activity is less than zero, it indicates that the catalyst is deactivated by carbon buildup, leading to a decline in reaction capacity. The heat release from hydrogenation in the bed is weakened, and the hydrogen consumption is reduced. If the original baseline is maintained, the hydrogenation depth will be insufficient, and the bed temperature will drop. Therefore, the fuel valve control baseline is increased by its baseline change to form a new fuel valve control baseline, in order to increase the reactor inlet temperature and compensate for the decrease in reaction rate caused by the loss of activity. The cold hydrogen valve control baseline is reduced by its baseline change to form a new cold hydrogen valve control baseline, in order to reduce the heat extraction from cold hydrogen and make more of the reaction heat used to maintain the bed temperature. The compressor speed control baseline is reduced by its baseline change to form a new compressor speed control baseline, in order to match the reduced hydrogen consumption and reduce compressor energy consumption while maintaining the hydrogen-to-oil ratio.

[0047] When the change in activity is zero, it indicates that the catalyst activity index at the current sampling moment is the same as the value at the previous moment, the catalyst reactivity has not changed, and the control reference has no basis for correction. Therefore, the fuel valve control reference, cold hydrogen valve control reference, and compressor speed control reference remain unchanged. The corrected control references are written into the data storage unit as the reference positions for adjusting the fuel valve opening, cold hydrogen valve opening, and compressor speed in subsequent steps. The actual opening and actual speed change around the corresponding reference positions during subsequent adjustments.

[0048] Please see Figure 2 As shown, Figure 2 This is a closed-loop logic diagram for adaptive tracking and benchmark correction of catalyst activity decay. The horizontal axis represents operating time, the left vertical axis represents the catalyst activity index, and the right vertical axis represents the control benchmark for the actuators (fuel valve, compressor). As operating time increases, the actual catalyst activity index gradually decreases. Existing technology maintains a fixed benchmark curve at a horizontal level, unaffected by the decrease in catalyst activity index. The fuel valve control benchmark curve increases stepwise with the decrease in catalyst activity index, while the compressor speed control benchmark curve decreases stepwise with the decrease in catalyst activity index. The correction direction is consistent with the benchmark correction direction when the activity change is less than zero. Therefore, the control benchmark is corrected synchronously with the catalyst activity decay, avoiding the response lag and compensation mismatch of manual correction.

[0049] S3. Using catalyst bed temperature as the controlled variable and cold hydrogen valve and fuel valve as actuators, adjust the opening of cold hydrogen valve or fuel valve when the catalyst bed temperature deviates from the bed temperature control reference, correct the compressor speed when the opening of cold hydrogen valve changes, and feedforward adjust the opening of downstream cold hydrogen valve when the opening of fuel valve changes.

[0050] Hydrogenation bed temperature regulation involves the coupled distribution of heat and material flow. The injection of cold hydrogen absorbs heat while altering the system's volumetric flow rate, thus affecting compressor operation. Heat shifts caused by fuel valve adjustments are transferred along the material flow, easily disrupting downstream thermal balance. Conventional single-loop systems sever this physical connection, often inducing pressure oscillations or downstream fluctuations during temperature corrections. After correcting the control baseline based on the activity index, this step, to mitigate deviations in bed temperature from this baseline during actual operation, uses bed temperature as the controlled variable to coordinately adjust the cold hydrogen valve and fuel valve. When the cold hydrogen valve actuates, the compressor speed is adjusted accordingly, and when the fuel valve actuates, feedforward intervention is provided to the downstream cold hydrogen valve, achieving dynamic compensation across multiple mechanisms.

[0051] Specifically, the maximum value among the temperatures of each catalyst bed is first taken as the controlled catalyst bed temperature, with the bed that releases the most heat being the target for temperature protection. The bed temperature control benchmark is taken as the maximum value among the stable operating temperatures of each bed recorded during the full-load calibration period when the sulfur content of the product is qualified. The temperature deviation is the difference between the controlled catalyst bed temperature and the bed temperature control benchmark. The temperature dead zone value is taken as twice the absolute value of the maximum allowable tolerance of the temperature sensing element at the bed temperature measuring point. The basis for this is that when the absolute value of the temperature deviation falls into this range, the deviation and the temperature measurement error are on the same order of magnitude, and it does not carry effective adjustment information.

[0052] The cold hydrogen valve refers to the cold hydrogen valve installed at the inlet of the currently controlled bed. The change in the cold hydrogen valve value is calculated by dividing the absolute value of the temperature deviation by the absolute value of the steady-state gain of the cold hydrogen valve opening on the bed temperature. Similarly, the change in the fuel valve value is calculated by dividing the absolute value of the temperature deviation by the absolute value of the steady-state gain of the fuel valve opening on the bed temperature. The steady-state gain of the cold hydrogen valve opening on the bed temperature and the steady-state gain of the cold hydrogen valve opening on the reactor inlet pressure are obtained from the same experiment, while the steady-state gain of the fuel valve opening on the bed temperature is obtained from a subsequent experiment. The experimental procedure was as follows: During the full-load calibration period, the opening of the cold hydrogen valve was increased by 5% of the full stroke of the valve and kept unchanged. After the bed temperature and reactor inlet pressure no longer changed with time, the bed temperature and reactor inlet pressure at two stable moments before and after the increase were recorded. The difference between the two bed temperatures was divided by the increase in opening to obtain the steady-state gain of the cold hydrogen valve opening on the bed temperature. The difference between the two reactor inlet pressures was divided by the increase in opening to obtain the steady-state gain of the cold hydrogen valve opening on the reactor inlet pressure.

[0053] Subsequently, the opening of the cold hydrogen valve was adjusted back to its previous value. After the bed temperature and reactor inlet pressure stabilized, the fuel valve opening was increased by 5% of the full valve stroke and held unchanged. The bed temperature at two stable moments before and after the increase in fuel valve opening was recorded in the same manner. The difference between the two bed temperatures was divided by the increase in opening to obtain the steady-state gain of fuel valve opening on bed temperature. The one-time increase in opening was taken as 5% of the full valve stroke, based on the fact that this increase is greater than the hysteresis of valve stroke, which can cause measurable changes in bed temperature and reactor inlet pressure, and the resulting bed temperature disturbance will not cause the sulfur content of the product to exceed the qualified range after dilution with cold hydrogen.

[0054] The upper limit of the opening of the cold hydrogen valve and the fuel valve is taken as the stroke corresponding to the fully open position of the valve, and the lower limit of the opening is taken as the stroke corresponding to the fully closed position of the valve; the upper limit of the compressor speed is taken as the maximum allowable continuous operating speed of the compressor, and the lower limit of the speed is taken as the minimum allowable speed determined based on the safety margin reserved for the surge boundary of the compressor performance curve.

[0055] Based on this, when the absolute value of the temperature deviation is greater than the temperature dead zone value, adjustment is performed according to the sign of the temperature deviation and the adjustment margin of the actuator: if the temperature deviation is greater than zero and the current opening of the cold hydrogen valve is less than the upper limit of the opening, it indicates that the bed temperature is higher than the baseline and there is still an adjustment margin for cold hydrogen injection. In this case, the current opening of the cold hydrogen valve is increased by its change as the new opening. The increased cold hydrogen is mixed into the reaction stream, directly diluting the reactant concentration and absorbing the heat of bed reaction. If the current opening of the cold hydrogen valve has reached the upper limit, it indicates that the adjustment capacity to increase the cold hydrogen injection by increasing the opening of the cold hydrogen valve has been exhausted. In this case, the current opening of the fuel valve is reduced by its change as the new opening. To achieve a new opening, the outlet material temperature of the heater is reduced, thus decreasing the heat entering the bed from the source. If the temperature deviation is less than zero and the current opening of the fuel valve is less than the upper limit, it indicates that the bed temperature is below the baseline and the hydrogenation depth is insufficient. In this case, the current opening of the fuel valve is increased by its change to determine the new opening, thereby increasing the inlet material temperature of the reactor to restore the reaction rate. If the current opening of the fuel valve has reached the upper limit, it indicates that the ability to increase the inlet material temperature of the reactor by increasing the fuel valve opening has been exhausted. In this case, the current opening of the cold hydrogen valve is reduced by its change to determine the new opening, thereby reducing the heat extraction from the cold hydrogen and allowing more of the heat released by the reaction to be used to maintain the bed temperature.

[0056] When the absolute value of the temperature deviation is less than or equal to the temperature dead zone value, it indicates that the deviation is within the measurement error range. The actual deviation direction and magnitude of the bed temperature relative to the reference cannot be obtained by measurement. The current opening of the cold hydrogen valve and the fuel valve should be kept unchanged to avoid repeated operation of the actuator within the measurement error range.

[0057] When the temperature deviation is greater than zero, the current opening of the cold hydrogen valve reaches its upper limit, and the current opening of the fuel valve reaches its lower limit, it indicates that both the cold hydrogen cooling and fuel reduction adjustment methods have been exhausted, but the bed temperature is still higher than the benchmark, and there is a risk of overheating in the bed. The controller issues a temperature runaway alarm signal. When the temperature deviation is less than zero, the current opening of the fuel valve reaches its upper limit, and the current opening of the cold hydrogen valve reaches its lower limit, it indicates that both the fuel heating and cold hydrogen reduction adjustment methods have been exhausted, but the bed temperature is still lower than the benchmark, and the hydrogen addition depth is insufficient. The controller issues a low temperature alarm signal.

[0058] Furthermore, changes in the opening degree of the cold hydrogen valve alter the gas volume flow rate entering the reaction system, causing fluctuations in the compressor delivery flow rate and reactor inlet pressure. The material temperature shift caused by changes in the fuel valve opening is transmitted along the material flow path via a transport delay to the downstream bed, causing the downstream bed temperature to deviate from its stable value. To compensate for this temperature shift before it reaches the downstream bed, after adjusting the opening degrees of the cold hydrogen and fuel valves, a coordinated compressor speed correction and downstream cold hydrogen valve feedforward adjustment are implemented. Specifically: the difference between the new and current cold hydrogen valve opening degrees is calculated as the actual change in the cold hydrogen valve. The speed change is taken as the quotient obtained by multiplying the absolute value of the actual change in the cold hydrogen valve by the steady-state gain of the cold hydrogen valve opening on the reactor inlet pressure, and then dividing by the steady-state gain of the compressor speed on the reactor inlet pressure. The steady-state gain of the cold hydrogen valve opening on the reactor inlet pressure has been determined in calibration tests along with the steady-state gain of the cold hydrogen valve opening on the bed temperature. The gain is obtained by increasing the compressor speed to the reactor inlet pressure in one step. The steady-state gain of the compressor speed to the reactor inlet pressure is obtained as follows: During the full-load calibration period, the compressor speed is increased by one percent of its rated speed and kept constant. After the reactor inlet pressure no longer changes with time, the reactor inlet pressure at two stable moments before and after the increase is recorded. The difference between the two reactor inlet pressures is divided by the increase in speed to obtain the steady-state gain of the compressor speed to the reactor inlet pressure. The increase in speed is taken as one percent of the rated speed, which is based on the fact that this magnitude is sufficient to cause a measurable pressure change without causing the compressor operating point to approach the surge boundary.

[0059] When the actual change in the cold hydrogen valve is greater than zero and the current compressor speed is greater than the lower limit of the speed, it indicates that the increase in cold hydrogen injection has increased the gas flow rate of the system and the reactor inlet pressure tends to rise. The current compressor speed minus the change in speed is taken as the new speed to reduce the compressor displacement and offset the pressure rise trend.

[0060] When the actual change in the cold hydrogen valve is greater than zero and the current compressor speed is less than or equal to the lower limit of the speed, it indicates that the speed has dropped to the minimum value allowed by anti-surge and cannot be further reduced. Keep the current speed unchanged, and the residual deviation of the reactor inlet pressure is handled by the subsequent pressure control loop.

[0061] When the actual change in the cold hydrogen valve is less than zero and the current compressor speed is less than the upper limit of the speed, it indicates that the reduction in the cold hydrogen injection volume has reduced the gas phase flow rate of the system and the reactor inlet pressure tends to decrease. The current compressor speed plus the change in speed is taken as the new speed to increase the compressor displacement and compensate for the pressure drop.

[0062] When the actual change in the cold hydrogen valve is less than zero and the current compressor speed is greater than or equal to the upper limit of the speed, it indicates that the speed has increased to the maximum continuous operating speed allowed by the compressor and cannot be increased further. The current speed is kept unchanged, and the residual deviation of the reactor inlet pressure is handled by the subsequent pressure control loop. When the actual change in the cold hydrogen valve is equal to zero, it indicates that the opening of the cold hydrogen valve has not changed, and the current compressor speed is kept unchanged.

[0063] Furthermore, the difference between the new fuel valve opening and the current opening is calculated as the actual change in the fuel valve. The downstream cold hydrogen valve refers to the cold hydrogen valve installed at the inlet of the next bed layer immediately adjacent to the current controlled bed layer along the material flow direction. The change in the downstream cold hydrogen valve is obtained by multiplying the absolute value of the actual change in the fuel valve by the absolute value of the steady-state gain of the fuel valve opening on the bed temperature, and then dividing by the absolute value of the steady-state gain of the downstream cold hydrogen valve opening on the downstream bed temperature. This ensures that the effect of the change in the downstream cold hydrogen valve opening on the downstream bed temperature exactly offsets the downstream bed temperature shift caused by the change in the fuel valve opening transmitted through the material flow.

[0064] When the actual change in the fuel valve is greater than zero, it indicates that the heat offset caused by the increase in the fuel valve opening will be transmitted to the downstream bed along with the material and cause its temperature to rise. The current opening of the downstream cold hydrogen valve plus its change is taken as the new opening of the downstream cold hydrogen valve to increase the cold hydrogen injection volume, offset the heat offset transmitted to the downstream bed, and maintain the downstream bed temperature stability.

[0065] When the actual change in the fuel valve is less than zero, it indicates that the cooling shift caused by the reduction in the fuel valve opening will be transmitted to the downstream bed along with the material flow and lower its temperature. The current opening of the downstream cold hydrogen valve minus its change is taken as the new opening of the downstream cold hydrogen valve to reduce the heat extraction of cold hydrogen, offset the cooling shift transmitted to the downstream bed, and maintain the temperature stability of the downstream bed.

[0066] When the actual change in the fuel valve is zero, it indicates that the fuel valve opening has not changed and the downstream bed cold hydrogen valve opening remains unchanged.

[0067] S4. Using the reactor inlet pressure as the controlled variable and the compressor speed as the actuator, the compressor speed is adjusted when the reactor inlet pressure deviates from the inlet pressure control reference, and the opening degree of the cold hydrogen valve of each bed is corrected in the reverse direction when the compressor speed changes.

[0068] The stability of the hydrogen refueling system pressure depends on the compressor speed regulation, but the increase or decrease of speed directly changes the total circulating hydrogen flow rate, thereby disrupting the predetermined cold hydrogen distribution ratio of each bed. Conventional single-loop pressure systems often overlook the implicit impact of this material reconfiguration on the bed thermal balance, and disturbances can easily be quietly transmitted to the temperature field during pressure stabilization. After completing temperature coordination regulation based on the activity correction benchmark, in order to prevent the negative transmission of pressure control to the thermal field, this step synchronously corrects the opening of the cold hydrogen valves in each bed in the reverse direction when the compressor speed is adjusted due to pressure deviation from the benchmark, in order to compensate for the temperature deviation caused by flow reconfiguration.

[0069] Specifically, the difference between the reactor inlet pressure and the inlet pressure control benchmark is first calculated as the pressure deviation value. The inlet pressure control benchmark is the stable operating value of the reactor inlet pressure recorded when the sulfur content of the product is qualified during the full-load calibration period of the unit. The speed change is taken as the quotient obtained by dividing the absolute value of the pressure deviation value by the steady-state gain of the compressor speed on the reactor inlet pressure. This steady-state gain has been obtained in the full-load calibration test, so that the pressure change caused by performing a speed adjustment according to this change is equal to the absolute value of the pressure deviation value.

[0070] Based on this, when the pressure deviation is greater than zero and the current compressor speed is greater than the lower limit, it indicates that the reactor inlet pressure is higher than its control reference and the compressor speed has a margin for adjustment. The current compressor speed minus the speed change is taken as the new speed. The speed reduction reduces the circulating hydrogen discharge, and the reactor inlet pressure falls back to near the control reference. When the pressure deviation is greater than zero and the current compressor speed is less than or equal to the lower limit, it indicates that the speed has dropped to the minimum allowable value for anti-surge. Further reduction will cause the compressor operating point to enter the surge zone. The current speed is kept unchanged and the controller issues a high pressure alarm signal.

[0071] When the pressure deviation is less than zero and the current compressor speed is less than the upper speed limit, it indicates that the reactor inlet pressure is lower than its control reference and the compressor speed has an upward adjustment margin. The current compressor speed plus the speed change is taken as the new speed. The increase in speed increases the circulating hydrogen discharge, and the reactor inlet pressure rises back to near the control reference. When the pressure deviation is less than zero and the current compressor speed is greater than or equal to the upper speed limit, it indicates that the speed has risen to the maximum allowable continuous operating speed of the compressor. The current speed is kept unchanged and the controller issues a low pressure alarm signal. When the pressure deviation is equal to zero, it indicates that the reactor inlet pressure is at the control reference. The current compressor speed is kept unchanged.

[0072] Furthermore, changes in compressor speed cause corresponding changes in the total circulating hydrogen flow rate, and the flow rate allocated to each bed cold hydrogen injection branch in the total flow rate changes accordingly. Deviations in the bed cold hydrogen injection rate from the original value will cause bed temperature shifts. To maintain a constant cold hydrogen injection rate in each bed while regulating pressure, the difference between the new compressor speed and the current speed is calculated as the actual change in speed. The change in the cold hydrogen valve of each bed is taken as the quotient obtained by multiplying the absolute value of the actual change in speed by the steady-state gain of the compressor speed on the reactor inlet pressure and dividing by the steady-state gain of the cold hydrogen valve opening on the reactor inlet pressure. Both steady-state gains have been obtained in the full-load calibration test. This change ensures that the change in reactor inlet pressure caused by the change in the opening of the cold hydrogen valve in each bed is equal in magnitude and opposite in direction to the change in pressure caused by the change in speed, and the flow distribution of each bed cold hydrogen injection branch is restored to the state before the speed change.

[0073] When the actual change in rotational speed is greater than zero and the current opening of the cold hydrogen valve in each bed is greater than the lower limit of the opening, it indicates that the increase in circulating hydrogen caused by the increase in rotational speed has begun to increase the amount of cold hydrogen injected into each bed. The current opening of the cold hydrogen valve in each bed minus its change is taken as the new opening to increase the branch resistance and offset the increase in the amount of cold hydrogen injected caused by the increase in circulating hydrogen.

[0074] When the actual change in rotational speed is greater than zero and the current opening of the cold hydrogen valve in each bed is less than or equal to the lower limit, it indicates that the opening of the cold hydrogen valve can no longer be reduced, and the current opening remains unchanged. When the actual change in rotational speed is less than zero and the current opening of the cold hydrogen valve in each bed is less than the upper limit, it indicates that the reduction in circulating hydrogen caused by the decrease in rotational speed has begun to reduce the amount of cold hydrogen injected into each bed. The current opening of the cold hydrogen valve in each bed is added to its change as the new opening to reduce the branch resistance and offset the reduction in the amount of cold hydrogen injected caused by the reduction in circulating hydrogen.

[0075] When the actual change in speed is less than zero and the current opening degree of the cold hydrogen valve in each bed is greater than or equal to the upper limit of the opening degree, it indicates that the opening degree of the cold hydrogen valve can no longer be increased and should remain unchanged. When the actual change in speed is equal to zero, it indicates that the compressor speed has not changed and the opening degree of the cold hydrogen valve in each bed remains unchanged.

[0076] Please see Figure 3 As shown, Figure 3This is a time-series diagram comparing the control effects under disturbance conditions. The horizontal axis represents time, and the vertical axes of the upper and lower sub-graphs represent the bed temperature fluctuation and reactor inlet pressure fluctuation, respectively. The vertical dashed line marks T0 as the disturbance occurrence point, caused by a sudden change in the raw material properties leading to a sudden rise in bed temperature. After T0, the temperature curve of the independent PID control experiences a slow recovery process accompanied by repeated oscillations, while the pressure curve exhibits a large secondary oscillation during the temperature recovery process, indicating a coupling disturbance between the temperature and pressure control loops. The temperature curve using the linkage decoupling compensation method of this invention quickly recovers to near the reference value, while the pressure curve only experiences small fluctuations and returns to stability. The above comparison shows that the feedforward and reverse compensation mechanisms, such as correcting the compressor speed when the cold hydrogen valve changes and reverse correcting the cold hydrogen valve opening when the compressor speed changes, reduce the coupling-induced deviations between multiple loops.

[0077] S5. Collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. Compare the control benchmark with the actual valve opening, actual speed, and actual measured values, and update the catalyst activity index.

[0078] After prior baseline correction and multi-mechanism adjustments, the unit enters a specific operating condition. However, due to fluctuations in raw materials and the dynamic characteristics of the equipment, the actual output of the actuators and the measured values ​​of the controlled variables often deviate from the control baseline. If only the initial extrapolated activity index is relied upon, this deviation will cause the activity assessment to become disconnected from the actual response state of the unit, weakening the matching degree of subsequent baselines. Therefore, this step collects the actual valve positions, speeds, and measured values ​​of temperature and pressure of each actuator, compares them with the corresponding control baselines to calculate the comprehensive deviation, and updates the catalyst activity index in a closed loop accordingly.

[0079] Specifically, at the end of each acquisition cycle, the maximum value among the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual compressor speed, the actual measured temperature of each catalyst bed, and the actual measured reactor inlet pressure are read. Then, the deviations between the actual valve opening of the fuel valve and the fuel valve control reference, the actual valve opening of the cold hydrogen valve and the cold hydrogen valve control reference, the actual compressor speed and the compressor speed control reference, the temperature deviation between the actual measured bed temperature and the bed temperature control reference, and the pressure deviation between the actual measured reactor inlet pressure and the inlet pressure control reference are calculated. The fuel valve control reference, the cold hydrogen valve control reference, and the compressor speed control reference are taken from the correction results written to the data storage unit in step S2, and the bed temperature control reference and the inlet pressure control reference are taken from the corresponding stable operating values ​​recorded during the full-load calibration period.

[0080] Based on this, the five deviations mentioned above are divided by the maximum allowable absolute value of their respective measuring points to obtain five dimensionless deviations. The absolute values ​​of the five dimensionless deviations are added together, and the sum is taken as the comprehensive deviation value. This comprehensive deviation value represents the overall degree of deviation between the actual output of the actuator and the measured value of the controlled variable relative to the control reference.

[0081] Then, the comprehensive deviation value is compared with the update threshold, which is the number of dimensionless deviation items. When the comprehensive deviation value is less than the update threshold, the average value of the five dimensionless deviations is less than one, and the average deviation of each item is lower than the inherent measurement error level of their respective measuring points, making it impossible to distinguish between actual deviation and measurement error.

[0082] When the overall deviation value is greater than the update threshold, it indicates that the actual deviation of the actuator and the controlled variable relative to the control reference exceeds the measurement error level, and the control reference is mismatched with the actual response state of the device. This mismatch mainly reflects the change in catalyst activity. The total deviation product is obtained by multiplying each deviation by the pre-calibrated weight coefficient and summing them. The updated catalyst activity index is obtained by subtracting the total deviation product from the current catalyst activity index.

[0083] The weighting coefficients are obtained as follows: During the full-load calibration period, the catalyst activity index and five corresponding deviations at each acquisition time within the calibration period are recorded. The five deviations are used as independent variables and the catalyst activity index is used as dependent variables. The linear equation system is solved using the conventional non-negative least squares method. The five non-negative coefficients obtained are used as the weighting coefficients of each deviation, so that the updated catalyst activity index decreases as the comprehensive deviation increases, which is consistent with the direction of catalyst activity decline. When the comprehensive deviation value is less than or equal to the update threshold, it indicates that each deviation is within the measurement error range, the control benchmark matches the actual response state of the device, and the current catalyst activity index remains unchanged.

[0084] The updated catalyst activity index is written to the data storage unit and overwrites the original value. It serves as the input for calculating the change in activity and performing baseline correction in step S2 at the next acquisition time, forming a closed loop from activity assessment, baseline correction, synergistic adjustment to activity reassessment.

[0085] Example 2

[0086] Please see Figure 4As shown, this invention provides an intelligent adaptive control system for a gasoline hydrogenation device, comprising: a data acquisition and activity calculation module, a reference correction module, a temperature control module, a pressure control module, and an activity update module. The connections between the modules are as follows: the data acquisition and activity calculation module is connected to the reference correction module; the reference correction module is connected to both the temperature control module and the pressure control module; the temperature control module and the pressure control module are bidirectionally connected; the temperature control module and the pressure control module are connected to the activity update module; and the activity update module is connected to the data acquisition and activity calculation module.

[0087] The data acquisition and activity calculation module is used to collect catalyst bed temperature, reactor inlet pressure and hydrogen concentration difference, and calculate catalyst activity index based on hydrogen concentration difference and bed temperature rise.

[0088] The reference correction module is used to synchronously correct the control references for the fuel valve, cold hydrogen valve, and compressor speed based on the catalyst activity index.

[0089] The temperature control module is used to adjust the opening of the cold hydrogen valve or the fuel valve when the catalyst bed temperature deviates from the bed temperature control reference, and to correct the compressor speed when the opening of the cold hydrogen valve changes, and to feedforward adjust the opening of the downstream cold hydrogen valve when the opening of the fuel valve changes.

[0090] The pressure control module is used to adjust the compressor speed when the reactor inlet pressure deviates from the inlet pressure control reference, and to reverse the opening degree of the cold hydrogen valves in each bed when the compressor speed changes.

[0091] The activity update module is used to collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. It compares the control benchmark with the actual valve opening, actual speed, and actual measured values ​​to update the catalyst activity index.

[0092] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0093] Those skilled in the art will recognize that the algorithmic steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0094] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0095] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0096] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A smart adaptive control method for a gasoline hydrogenation unit, characterized in that, include: The catalyst bed temperature, reactor inlet pressure, and hydrogen concentration difference were collected, and the catalyst activity index was calculated based on the hydrogen concentration difference and bed temperature rise. The control reference for the fuel valve, cold hydrogen valve and compressor speed is simultaneously corrected using the catalyst activity index; With catalyst bed temperature as the controlled variable and cold hydrogen valve and fuel valve as actuators, the opening of cold hydrogen valve or fuel valve is adjusted when the catalyst bed temperature deviates from the bed temperature control reference. When the opening of cold hydrogen valve changes, the compressor speed is corrected. When the opening of fuel valve changes, the opening of downstream cold hydrogen valve is adjusted forward. The reactor inlet pressure is used as the controlled variable and the compressor speed is used as the actuator. When the reactor inlet pressure deviates from the inlet pressure control reference, the compressor speed is adjusted. When the compressor speed changes, the opening of the cold hydrogen valve in each bed is corrected in the opposite direction. Collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. Compare the control benchmark with the actual valve opening, actual speed, and actual measured values ​​to update the catalyst activity index.

2. The intelligent adaptive control method for a gasoline hydrogenation device as described in claim 1, characterized in that, The method for obtaining the catalyst activity index includes: The difference between the hydrogen concentration at the reactor inlet and outlet is taken as the hydrogen concentration difference, and the difference between the catalyst bed outlet and inlet temperature is taken as the bed temperature rise. When the bed temperature rise is greater than the preset temperature threshold, the ratio of the hydrogen concentration difference to the bed temperature rise is calculated to obtain the hydrogen consumption temperature rise ratio; when the bed temperature rise is less than or equal to the threshold, the catalyst activity index at the previous moment is used as the current catalyst activity index. When the hydrogen consumption temperature rise ratio is greater than zero and the bed temperature rise is greater than the preset temperature threshold, the relative hydrogen concentration difference is obtained by dividing the hydrogen concentration difference by the initial hydrogen concentration difference, and the relative bed temperature rise is obtained by dividing the bed temperature rise by the initial bed temperature rise. The arithmetic mean of the relative hydrogen concentration difference and the relative bed temperature rise is used as the catalyst activity index.

3. The intelligent adaptive control method for a gasoline hydrogenation device as described in claim 1, characterized in that, The control reference for the fuel valve, cold hydrogen valve, and compressor speed is simultaneously corrected based on the catalyst activity index, specifically including: The difference between the catalyst activity index at the current moment and at the previous moment is calculated as the change in activity. When the change in activity is greater than zero, the current opening of the fuel valve minus its reference change is used as the fuel valve control reference, the current opening of the cold hydrogen valve plus its reference change is used as the cold hydrogen valve control reference, and the current compressor speed plus its reference change is used as the compressor speed control reference. When the change in activity is less than zero, the current opening of the fuel valve plus its reference change is used as the fuel valve control reference, the current opening of the cold hydrogen valve minus its reference change is used as the cold hydrogen valve control reference, and the current compressor speed minus its reference change is used as the compressor speed control reference. When the change in activity is zero, the current control baseline remains unchanged.

4. The intelligent adaptive control method for a gasoline hydrogenation device as described in claim 1, characterized in that, When the catalyst bed temperature deviates from the bed temperature control benchmark, the opening of the cold hydrogen valve or the fuel valve is adjusted, specifically including: Calculate the temperature deviation between the catalyst bed temperature and the bed temperature control baseline; When the absolute value of the temperature deviation is greater than the preset temperature dead zone value: If the temperature deviation is greater than zero and the current opening of the cold hydrogen valve is less than the upper limit of the opening, then the current opening of the cold hydrogen valve is increased by the change to obtain the new opening; if the current opening of the cold hydrogen valve has reached the upper limit of the opening, then the current opening of the fuel valve is decreased by the change to obtain the new opening. If the temperature deviation is less than zero and the current opening of the fuel valve is less than the upper limit of the opening, then the current opening of the fuel valve is increased by the change to obtain the new opening; if the current opening of the fuel valve has reached the upper limit of the opening, then the current opening of the cold hydrogen valve is decreased by the change to obtain the new opening. When the absolute value of the temperature deviation is less than or equal to the preset temperature dead zone value, the current opening degree of the cold hydrogen valve and the fuel valve remains unchanged. When the temperature deviation is greater than zero, the current opening of the cold hydrogen valve reaches the upper limit, and the current opening of the fuel valve reaches the lower limit, a temperature runaway alarm signal is issued.

5. The intelligent adaptive control method for a gasoline hydrogenation device as described in claim 4, characterized in that, The compressor speed is corrected when the opening degree of the cold hydrogen valve changes, specifically including: The difference between the new cold hydrogen valve opening and the current opening is calculated as the actual change in the cold hydrogen valve. When the actual change in the cold hydrogen valve is greater than zero and the current compressor speed is greater than the lower limit, the current speed minus the change in speed is taken as the new speed; when the change in speed is greater than zero and the current speed is less than or equal to the lower limit, the current speed is kept unchanged. When the actual change in the cold hydrogen valve is less than zero and the current compressor speed is less than the upper limit of the speed, the current speed plus the change in speed is taken as the new speed.

6. The intelligent adaptive control method for a gasoline hydrogenation unit as described in claim 4, characterized in that, When the fuel valve opening changes, the downstream cold hydrogen valve opening is adjusted via feedforward, specifically including: The difference between the new fuel valve opening and the current opening is calculated as the actual change in the fuel valve opening. When the actual change in the fuel valve is greater than zero, the current opening of the downstream cold hydrogen valve is added to the change to obtain the new opening of the downstream cold hydrogen valve. When the actual change in the fuel valve is less than zero, the current opening of the downstream cold hydrogen valve is subtracted from the change to obtain the new opening of the downstream cold hydrogen valve. When the actual change in the fuel valve is zero, the current opening of the downstream cold hydrogen valve remains unchanged.

7. The intelligent adaptive control method for a gasoline hydrogenation unit as described in claim 1, characterized in that, When the reactor inlet pressure deviates from the inlet pressure control reference, the compressor speed is adjusted, specifically including: Calculate the pressure deviation between the reactor inlet pressure and the inlet pressure control reference. When the pressure deviation is greater than zero and the current compressor speed is greater than the lower limit, the current speed is subtracted from the speed change to obtain the new speed; when the pressure deviation is greater than zero and the current speed is less than or equal to the lower limit, the current speed is kept unchanged and a high pressure alarm is issued. When the pressure deviation is less than zero and the current speed is less than the upper limit of speed, the current speed is added to the speed change as the new speed; when the pressure deviation is less than zero and the current speed is greater than or equal to the upper limit of speed, the current speed is kept unchanged and a low pressure alarm is issued.

8. The intelligent adaptive control method for a gasoline hydrogenation unit as described in claim 7, characterized in that, When the compressor speed changes, the opening degree of the cold hydrogen valves in each bed is corrected in reverse, specifically including: The difference between the new compressor speed and the current speed is calculated as the actual change in speed; When the actual change in rotational speed is greater than zero and the current opening of the cold hydrogen valve in each bed is greater than the lower limit of the opening, the current opening of the cold hydrogen valve in each bed is reduced by the change to obtain the new opening; when the change is greater than zero and the opening is less than or equal to the lower limit, the current opening remains unchanged. When the actual change in rotational speed is less than zero and the current opening of the cold hydrogen valve in each bed is less than the upper limit of the opening, the current opening of the cold hydrogen valve in each bed is increased by the change to obtain the new opening; when the change is less than zero and the opening is greater than or equal to the upper limit, the current opening remains unchanged.

9. The intelligent adaptive control method for a gasoline hydrogenation device as described in claim 1, characterized in that, The catalyst activity index is updated by comparing the control benchmark with the actual valve opening, actual rotational speed, and actual measured values. Specifically, this includes: Calculate the deviations of the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual compressor speed, the actual measured bed temperature, and the actual measured reactor inlet pressure from their corresponding control references. Divide each of the above deviations by the maximum allowable absolute value of its respective measuring point to obtain five dimensionless deviations. Calculate the sum of the absolute values ​​of the five dimensionless deviations as the comprehensive deviation value. When the overall deviation value is greater than the preset update threshold, the dimensionless deviations of each item are multiplied by the pre-calibrated weighting coefficients and then summed to obtain the total deviation weighted value. The current catalyst activity index is then subtracted from the total deviation weighted value to obtain the updated catalyst activity index. When the overall deviation value is less than or equal to the preset update threshold, the current catalyst activity index remains unchanged.

10. An intelligent adaptive control system for a gasoline hydrogenation device, characterized in that, include: The data acquisition and activity calculation module is used to collect catalyst bed temperature, reactor inlet pressure and hydrogen concentration difference, and calculate catalyst activity index based on hydrogen concentration difference and bed temperature rise. The reference correction module is used to synchronously correct the control references of the fuel valve, cold hydrogen valve and compressor speed based on the catalyst activity index. The temperature control module is used to adjust the opening of the cold hydrogen valve or the fuel valve when the catalyst bed temperature deviates from the bed temperature control reference, correct the compressor speed when the opening of the cold hydrogen valve changes, and adjust the opening of the downstream cold hydrogen valve when the opening of the fuel valve changes. The pressure control module is used to adjust the compressor speed when the reactor inlet pressure deviates from the inlet pressure control reference, and to reverse the opening degree of the cold hydrogen valves of each bed when the compressor speed changes. The activity update module is used to collect the actual valve opening of the fuel valve, the actual valve opening of the cold hydrogen valve, the actual speed of the compressor, the actual measured value of the catalyst bed temperature, and the actual measured value of the reactor inlet pressure. It compares the control benchmark with the actual valve opening, actual speed, and actual measured values ​​to update the catalyst activity index.

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