An adaptive control method for disinfectant production

Abstract

The present application relates to the technical field of disinfectant production, and more particularly to a self-adaptive regulation method for disinfectant production, comprising: collecting real-time gas pressure data of a raw material gas feeding pipeline; performing time differential operation on the gas pressure data to obtain a real-time gas pressure change derivative; setting a warning derivative threshold value to determine whether the real-time gas pressure change derivative is greater than the warning derivative threshold value, and if the determination result is yes, responding to detection of a local thermal runaway risk and performing a transient suppression operation: opening a high-speed cut-off valve connected to a lye feeding main flow channel and directly injecting low-temperature process water into the lye feeding main flow channel through a high-pressure nozzle. The present application solves the physical time lag problem of traditional external jacket cooling, avoids the initiation of side reactions caused by local thermal runaway, ensures that the product concentration after dilution by water injection can be accurately restored and stabilized within the qualified standard, and greatly improves the yield rate and equipment operation safety of disinfectant continuous production.

Description

Technical Field

[0001] This invention relates to the field of disinfectant production technology. More specifically, this invention relates to an adaptive control method for disinfectant production. Background Technology

[0002] In modern continuous production processes for disinfectants, a gaseous gas (such as chlorine) is typically continuously fed into a reactor containing an alkaline solution to initiate a gas-liquid phase chemical reaction. To maintain a steady reaction, the industry has primarily relied on external cooling water jackets to remove the heat generated during the reaction, combined with conventional feedback controllers to passively adjust valve openings and material ratios. However, with the continuous expansion of production lines and increasing capacity requirements, production conditions are becoming increasingly complex, and the process challenges posed by pipeline pressure fluctuations are becoming more pronounced.

[0003] In related technologies, for example, Chinese patent application CN120779750A discloses a disinfectant concentration adaptive control and green production optimization system and method, which constructs a concentration control... Effect verification The energy-efficient, end-to-end collaborative closed-loop system significantly improves the precision of disinfectant concentration control, greatly enhances the timeliness of disinfection effect verification, and significantly improves energy consumption and environmental friendliness in the production process. It is applicable to production scenarios of liquid disinfectants, aerosol disinfectants, disinfectant gels, and other products, and comprehensively improves the precision and greenness of hygiene and disinfection production.

[0004] However, in actual high-load continuous production scenarios, existing external jacket cooling mechanisms and passively waiting for temperature rise in macroscopic control modes have serious physical limitations. When transient surges occur in the production pipeline or the feed gas pressure surges, the jet kinetic energy of the gas entering the liquid phase through the distributor increases sharply. The high shear force causes the bubbles to be instantly shattered into extremely small bubble clusters, resulting in an exponential expansion of the gas-liquid contact surface area. The reaction rate in the local reaction zone instantly reaches its peak, leading to severe local hot spots. At this time, due to the thermal resistance of the thick metal vessel wall and the inherent time difference in fluid mixing, the cooling heat transfer rate of the traditional external jacket is far lower than the rate of local temperature rise. This physical cooling lag makes it impossible for the system to suppress transient thermal runaway in time, which can easily induce serious side reactions. This not only leads to a large amount of ineffective consumption of raw materials and abnormal fluctuations in the effective chlorine concentration of the product, but also significantly reduces the overall yield of the production line, and in severe cases, even endangers the operational safety of the reaction equipment. Summary of the Invention

[0005] This invention provides an adaptive control method for disinfectant production, aiming to solve the problem that in related technologies, the cooling and heat transfer rate of the traditional external jacket is much lower than the rate of local temperature rise. This physical cooling lag makes it impossible for the system to suppress transient thermal runaway in time, resulting in a large amount of ineffective consumption of raw materials, abnormal fluctuations in the effective chlorine concentration of the product, and a significant decrease in the overall yield of the production line.

[0006] This invention provides an adaptive control method for disinfectant production, comprising: real-time acquisition of gas pressure data from the feed pipeline of raw material gas; performing time differentiation on the gas pressure data to obtain the real-time gas pressure change derivative; setting a warning derivative threshold that characterizes the upper limit of normal process pressure fluctuation; determining whether the real-time gas pressure change derivative is greater than the warning derivative threshold; if the determination result is yes, the response is to detect the risk of local thermal runaway and perform an instantaneous suppression operation: opening a high-speed shut-off valve connected to the main feed channel of alkali solution, and directly injecting low-temperature process water into the main feed channel of alkali solution through a high-pressure nozzle until the gas pressure change derivative is lower than the warning derivative threshold, wherein the injection volume of low-temperature process water is proportional to the difference between the real-time gas pressure change derivative and the warning derivative threshold. Based on differential pressure calculations, abnormal conditions such as transient surges or feed spikes are accurately predicted in advance. When a risk of local thermal runaway is detected, low-temperature process water is directly and quantitatively injected into the main feed channel of the alkali solution. This direct injection method, which bypasses the heat transfer path of the thick metal reactor wall, can utilize the huge specific heat capacity of liquid water to absorb excess heat energy on-site at the moment the reaction hot spot is generated. This effectively overcomes the shortcomings of traditional temperature control that passively waits for the temperature to rise before responding, and effectively avoids malignant side reactions and equipment overpressure hazards induced by instantaneous high temperature. It fundamentally improves the yield rate of high-purity disinfectant production lines and the operational safety of core equipment in high-load continuous production scenarios.

[0007] Furthermore, the method for setting the early warning derivative threshold includes: continuously collecting pressure change derivative data sequences under stable system operating conditions; calculating the mean and standard deviation of the data sequences; and setting the early warning derivative threshold to the ratio of the mean to the standard deviation of the data sequences. The sum of multiple standard deviations. By dynamically establishing the early warning boundary through the statistical distribution law of objective air pressure data obtained under stable system operating conditions, the setting of the early warning threshold can closely match the real normal process fluctuation background of different production lines. This effectively avoids the risk of false triggering or missed reporting caused by using rigid fixed empirical parameters, and ensures extremely high sensitivity and anti-interference reliability of transient thermal runaway monitoring under complex operating conditions.

[0008] Furthermore, the calculation method for the cryogenic process water injection volume is as follows: the difference between the real-time pressure change derivative and the warning derivative threshold is multiplied by a preset volume compensation coefficient to obtain the target injection flow rate. The target injection flow rate is directly proportional to the degree of pressure surge, ensuring that the additional cooling medium introduced into the reactor is just enough to suppress the current surge in heat. This prevents insufficient cooling from failing to contain thermal runaway, while also avoiding excessive cooling that leads to over-diluted products and significantly increases the control costs for subsequent concentration recovery.

[0009] Furthermore, the method for determining the volume compensation coefficient includes: pre-calculating the excess heat release caused by a unit pressure increase and the heat absorbed by a unit volume of cryogenic process water, and using the ratio of the excess heat release to the absorbed heat as the volume compensation coefficient. The underlying thermodynamic logic based on energy conservation provides a solid physical basis for obtaining the volume compensation coefficient, enabling the system to accurately map the abstract pipeline pressure increase into real excess heat release energy, thereby precisely matching the physical heat absorption capacity of specific cryogenic process water and achieving a dynamic balance between heat supply and demand.

[0010] Furthermore, after the transient suppression operation ends, a concentration recovery operation is performed, including: stopping the injection of low-temperature process water after the real-time pressure change derivative falls below the warning derivative threshold; integrating and accumulating the total amount of low-temperature process water injected during the transient suppression operation; and in the subsequent stable production stage, increasing the basic feed rates of raw material gas and alkali solution according to a preset compensation ratio until the volume of the replenished reaction products offsets the total amount of injected low-temperature process water. By accurately recording the total volume of pure water introduced due to transient suppression through precise time integration, and orderly replenishing the offset reaction products in a controlled, cumulative feeding manner during the stable production stage of gas pressure recovery, the problem of temporary dilution of product concentration inevitably accompanied by sudden cooling is effectively resolved. This ensures that the average effective chlorine concentration of the disinfectant product is not affected by sudden operating conditions throughout the entire continuous production cycle, and greatly reduces the production rate of substandard waste liquid.

[0011] Furthermore, the concentration recovery operation also includes: while simultaneously increasing the feed rate, reducing the operating frequency of the finished product discharge pump at the bottom of the reactor to extend the residence time of the mixture within the reactor. During the process of increasing the feed rate to compensate for the concentration, by actively reducing the speed of the finished product discharge pump to decrease the physical flow rate, the reactor's own physical volume provides a longer residence and mixing time for the newly added high-concentration reactants and the diluted materials. This effectively smooths out the concentration distribution gradient caused by the initial instantaneous water injection from a fluid dynamics perspective, ensuring that the final liquid flowing into the finished product tank achieves highly homogenized physicochemical quality.

[0012] Furthermore, feedforward control of the basic material ratio is implemented, including: real-time acquisition of the mass flow rate of the raw gas; calculation of the corresponding theoretical alkali feed rate based on the set target molar flow ratio and the molar mass of the raw gas; and control of the operating frequency of the alkali feed pump to ensure that the actual alkali mass flow rate reaches the theoretical alkali feed rate. Based on this enhanced control foundation for handling sudden hotspot out-of-control situations, a primary feedforward tracking capability based on theoretical reaction equations and real-time gas mass is established. This ensures that the alkali pumping rate under normal conditions can always be synchronously matched with macroscopic fluctuations in the input gas volume with low delay, thus curbing early and drastic concentration drift caused by imbalances in the molar ratio of basic materials at its source.

[0013] Furthermore, the feedforward control of the basic material proportioning also includes: multiplying the collected raw material gas mass flow rate by the enthalpy constant to obtain the theoretical total heating power; calculating the theoretical cooling water demand based on the theoretical total heating power; and adjusting the opening of the cooling water inlet valve flowing through the external cooling jacket of the reactor. This expands the system's feedforward prediction scope from the material mass dimension to the macroscopic heat dimension, enabling the prediction of the overall theoretical heating power in advance based on the real-time gas intake and the pre-adjustment of the water flow opening in the external jacket.

[0014] Furthermore, it also includes: PID closed-loop control of the main reaction temperature inside the reactor and the oxidation-reduction potential at the product outlet: if the main reaction temperature exceeds the safety threshold, the opening of the cooling water inlet valve is increased; if the oxidation-reduction potential deviates from the set range, the alkali feed rate is finely adjusted to ensure that the free alkalinity at the reaction endpoint is qualified. Based on the synergistic complementarity of multidimensional feedforward tracking and transient limit suppression, a classic reaction parameter closed-loop feedback correction is introduced as a system fallback strategy. This strategy can absorb and mitigate the slow parameter drift caused by unmeasurable external disturbances such as alternating environmental temperatures and slight variations in raw material batch purity in real time, thus firmly maintaining the high robustness required for the production of qualified free alkalinity in complex large-scale production systems under long-term operation.

[0015] Furthermore, the method also includes an adaptive optimization step: collecting the actual effective chlorine concentration of the final product; corresponding to the actual effective chlorine concentration returning to the qualified range, the system instructs the discharge pump frequency converter to resume normal operation frequency to maintain production capacity; corresponding to the system detecting that although the actual effective chlorine concentration is within the qualified range, there is still a slight static deviation from the set target value, the target molar flow ratio is adaptively corrected to eliminate the static deviation. The highest-level adaptive optimization decision-making closed loop is constructed using the real physicochemical detection values ​​of high-precision sensors at the pipeline end. This enables the system not only to have the ability to mitigate risks and recover itself, but also to automatically identify and eliminate the slight deviations of various implicit static cumulative errors from the product's set target after production capacity is restored. This endows the entire system with intelligent self-correction attributes, achieving a quality leap from broad compliance to precise target point locking for the core indicators of the disinfectant leaving the factory.

[0016] Beneficial Effects: Addressing the industry pain points of traditional disinfectant continuous production, such as severe lag in external jacket heat transfer and susceptibility to localized thermal runaway or even malignant side reactions induced by sudden changes in feed pressure, an adaptive control technology architecture integrating physical direct cooling and chemical optimization was constructed. Its core concept lies in breaking away from the conventional passive waiting-for-heat feedback limitation. It utilizes the differential pressure-time mechanism to achieve millisecond-level forward warning of thermal runaway risks and employs computationally quantified ultra-low temperature pure water direct injection into the main alkaline solution channel to instantaneously extinguish surges in heat energy at the microscopic gas-liquid mixing node. Combined with a closed-loop integral compensation homogenization mechanism and electrochemical step-by-step correction after the crisis is resolved, the process achieves both explosion-proof safety during production and extreme stability of the final effective chlorine concentration without sacrificing production line continuity, significantly improving the overall yield of the prepared product. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart illustrating the control method according to Embodiment 1 of the present invention; Figure 2 This is a schematic flowchart illustrating the control method according to Embodiment 2 of the present invention; Figure 3 This is a schematic diagram illustrating the comparison between the stability of the effective chlorine concentration of the product and the compensation effect according to an embodiment of the present invention. Detailed Implementation

[0018] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0019] Example 1: S101: Multi-source operation data acquisition and feedforward control of basic material proportioning.

[0020] In this embodiment, in the continuous disinfectant production system, sensor arrays deployed on various pipelines and reactors collect multi-source physical quantity data of the production process in real time. Specifically, the collected data includes: real-time gas pressure and mass flow rate on the raw material gas (chlorine) feed pipeline; real-time mass flow rate and feed temperature on the alkaline solution (sodium hydroxide) feed pipeline; the main reaction temperature inside the reactor and the redox potential at the product discharge outlet; and the inlet water temperature and flow rate of the external cooling water jacket. The collected raw data is then subjected to moving average filtering to remove transient noise caused by electromagnetic interference, resulting in a smoothed reference data sequence for subsequent control logic calls.

[0021] In Example 1, the problem of heat and concentration control in disinfectant production is solved, and the complete implementation steps are as follows.

[0022] First, the system sets the target molar flow ratio of feed gas to alkali solution based on the theoretical chemical reaction equation. Based on the real-time collected feed gas mass flow rate, the system calculates the required theoretical alkali solution feed rate using its built-in multiplier module and directly outputs a control signal to adjust the frequency of the alkali solution feed pump, achieving feedforward matching of the base concentration.

[0023] In this embodiment, the specific process for calculating the required theoretical alkali feed rate is as follows: First, the smoothed raw material gas mass flow rate obtained in step S101 is read and divided by the chlorine molecular weight and raw material purity to calculate the actual molar feed rate of chlorine at the current moment; then, the chlorine molar feed rate is multiplied by the set target molar flow rate ratio to obtain the molar consumption rate of pure sodium hydroxide required for the reaction; finally, the pure sodium hydroxide molar consumption rate is multiplied by the sodium hydroxide molecular weight and divided by the alkali mass concentration percentage to calculate the required theoretical alkali feed rate at the current moment.

[0024] After obtaining the theoretical alkali feed rate, it is compared with the actual alkali mass flow rate measured by the flow meter. Based on the deviation value, a standard analog control signal is output to the frequency converter connected to the alkali feed pump motor. This signal instructs the frequency converter to change the Hertz frequency of its output AC power, so that the actual amount of alkali fed into the reactor reaches the calculated theoretical alkali feed rate, ensuring the material ratio balance.

[0025] S102: Heat balance and PID closed-loop correction.

[0026] Continuing from the above, using the preset enthalpy constant of the reaction generation heat, the previously calculated chlorine molar feed rate is multiplied by the enthalpy constant to calculate the theoretical total heat generation power of the current reaction. Subsequently, the system calculates the theoretical cooling water requirement based on this total heat generation power and controls the cooling water inlet valve to reach the corresponding opening degree, thereby adjusting the amount of cooling water flowing through the jacket to remove heat.

[0027] Based on the above feedforward actions, the system continuously monitors the main reaction temperature in the reactor. If the main reaction temperature exceeds the set safety threshold, the standard PID controller will calculate the compensation value based on the temperature deviation and further fine-tune the opening of the cooling water valve. The safety threshold is 35 degrees Celsius. Similarly, if the oxidation-reduction potential at the product outlet deviates from the target range, the PID controller will fine-tune the opening of the alkali feed valve to ensure that the free alkalinity at the reaction endpoint is qualified.

[0028] Example 2: While Example 1 addresses the macroscopic material and heat balance issues, its reliance on external jacket cooling cannot effectively mitigate the thermal resistance of the heat transfer walls and the time difference in fluid mixing. If the feed gas pressure experiences a transient surge, the temperature rise in the local reaction zone will be much faster than the heat transfer rate of the jacket cooling, leading to side reactions.

[0029] S201: Monitoring and assessment of the risk of sudden air pressure changes.

[0030] The system no longer simply passively waits for the temperature to rise, but instead... The differential command performs continuous time-differential calculations on the smoothed gas pressure data obtained in the first step to obtain the derivative of the gas pressure change, i.e., the pressure rise rate. According to the underlying logic of fluid mechanics and reaction kinetics, a sudden increase in the pressure rise rate means a sharp increase in the injection kinetic energy of the gas as it enters the liquid phase through the distributor's micro-orifices. This not only causes a sudden increase in the amount of chlorine gas injected per unit time, but more critically, the high shear force causes the chlorine bubbles to be shattered into extremely small bubble clusters. The smaller the bubbles, the more exponentially the gas-liquid contact surface area expands, causing the reaction rate to reach its peak instantaneously and generating intense local hot spots. Therefore, the system in... A warning derivative threshold is set, which represents the upper limit of normal pipeline surge. The system compares the calculated pressure change derivative with the warning derivative threshold in real time.

[0031] Continuing from the previous point, the method for obtaining the early warning derivative threshold is as follows: During stable system operation, pressure change rate data is collected in real time, and its average value and standard deviation are calculated. The early warning derivative threshold is set as the average value plus N times the standard deviation. Typically, N is set to 3-5; in this embodiment, N is set to 4. This value represents the upper limit of normal process fluctuations; exceeding this value indicates a risk of transient pressure surge.

[0032] S202: Instantaneous suppression and regulation of local thermal runaway.

[0033] When the current pressure change derivative is less than the warning derivative threshold, it indicates that production is within the normal macroscopic fluctuation range, and the system maintains only the basic control logic in Example 1. When the system determines that the pressure change derivative is greater than or equal to the warning derivative threshold, it indicates that local thermal runaway is about to occur. At this time, the system immediately triggers in-depth control: the system does not immediately and significantly increase the frequency of the inverter to increase the feed of room temperature alkali solution to prevent further runaway of heat generation due to the rapid accumulation of the total amount of reactants, but instead triggers a physical branch in parallel: A high-speed digital signal is emitted to instantly open the high-speed pneumatic shut-off valve installed at the end of the alkali feed main pipe, forcibly injecting ultra-low temperature pure process water from the refrigeration unit directly into the alkali feed main through a high-pressure nozzle until the pressure change derivative falls below the warning derivative threshold. The instantaneous compensation water volume is not random, but is calculated by multiplying the difference between the current pressure change derivative and the warning derivative threshold by a preset volume compensation coefficient. The higher the difference exceeds the warning derivative threshold, the greater the intervention pressure and flow rate of the high-pressure nozzle. The preset volume compensation coefficient is obtained by pre-calculating the excess reaction heat generated per unit pressure increment and the heat absorbed per unit volume of low-temperature water, based on the law of conservation of energy. The volume compensation coefficient is the ratio of the excess reaction heat release to the heat absorption capacity of the low-temperature water. The ultra-low temperature process water directly enters the core reaction area as part of the material, bypassing the thick metal vessel wall and the long path of water flow in the jacket. Utilizing the huge specific heat capacity of liquid water, it absorbs heat energy on-site the instant the hot spot is generated, effectively solving the physical time lag problem of external cooling.

[0034] Additional purified water was forcibly injected to suppress transient thermal runaway, which will cause transient dilution of the disinfectant solution generated in the reactor, resulting in a temporary drop in the effective chlorine concentration of the product below the finished product standard. To ensure the overall product quality is up to standard during continuous production, the system must perform the following complete concentration compensation and system recovery procedures after the hotspot crisis is resolved.

[0035] The system continuously monitors the derivative of air pressure changes in the background. When the air pressure surge pulse passes and the derivative of air pressure changes falls back and stabilizes below the warning derivative threshold, The opening signal of the high-speed pneumatic shut-off valve is cut off, stopping the injection of cryogenic process water. During this process... The internal integrator module integrates the flow meter data on the cryogenic process water pipeline over time to accurately calculate the total volume of additional purified water injected into the reactor during the thermal runaway suppression.

[0036] After the system obtains the total volume of the additional injected purified water, it automatically enters the concentration recovery mode. Firstly, to prevent substandard diluted disinfectant from rapidly flowing into the finished product tank, By outputting control signals, the operating frequency of the inverter motor of the finished product discharge pump at the bottom of the reactor is actively reduced. The purpose is to slow down the pump's rotation speed, reduce the physical discharge flow rate, and thus extend the residence and homogenization time of the current batch of mixture inside the reactor. During this homogenization period, the system uses the calculated total volume of purified water as a compensation base. Based on the standard concentration ratio of the disinfectant, the total amount of additional raw material consumption required to offset this volume of purified water is calculated. During the subsequent stable pressure operation phase, the system adds feed according to a set compensation ratio of 3% above the theoretical target value calculated in Example 1; and the real-time accumulated amount of these additional feeds is statistically analyzed. When the accumulated value reaches the aforementioned calculated total amount of additional raw material consumption, it indicates that the supplemented reaction product volume offsets the total amount of injected low-temperature process water, the 3% added feed is stopped, and the normal frequency of the discharge pump is restored. By accurately replenishing the reaction products during the stable period and utilizing long-term stirring and homogenization within the reactor, the average concentration previously lowered due to water injection is brought back up to the acceptable range.

[0037] For example, in the production of a disinfectant with an effective chlorine concentration of 10%, when the pressure surges, the system instantly injects 50L of ultra-low temperature purified water to cool it down. At this time, the original 10% concentration in the reactor is diluted, for example, to 9.5%. Then, a concentration recovery operation begins: the discharge pump speed is reduced, allowing the material to remain in the reactor longer for thorough mixing. The system then adds 3% more raw material than before. The high-concentration product generated by the reaction of this extra 3% of raw material enters the reactor and mixes with the initial 50L of purified water. Over time, the dilution effect of the initial 50L of ultra-low temperature purified water is gradually offset by the additional 3% of product, thus restoring the concentration to 10%.

[0038] S204: Product quality inspection and adaptive optimization.

[0039] When the homogenized and compensated disinfectant flows out of the reactor and into the final detection pipeline, a combination of a high-precision online refractometer and an electrochemical sensor installed on the pipeline performs real-time detection of the final product. The refractometer calculates the actual effective chlorine concentration of the final product based on the physical law of the change in solution refractive index with concentration, while the electrochemical sensor verifies the remaining free alkalinity. The system executes a dual judgment logic based on the detection results: First, a range compliance judgment: if the actual effective chlorine concentration displayed by the refractometer returns to the qualified range, such as 9.8%-10.2%, it indicates that the effect of water dilution has been basically eliminated, and the system instructs the discharge pump frequency converter to resume normal operation to maintain production capacity. Second, precision optimization calibration: after the discharge pump resumes normal operation, if the system detects that although the actual effective chlorine concentration is within the qualified range, there is still a slight static deviation from the set target value, such as a concentration difference of 0.2%, then an adaptive optimization logic is triggered. At this time, the system uses the potential difference value as a feedback signal to fine-tune the raw material ratio from the source by gradually correcting the target molar flow ratio, thereby eliminating the static deviation and accurately locking the product at the target value point. For example, in precision optimization calibration, if the refractometer shows a concentration of 10.2% after the water injection crisis ends, while the target value is set to 10.0%, this 0.2% difference is considered a static concentration deviation.

[0040] The method for correcting the target molar flow ratio in a step-by-step manner is as follows: An internally preset standard safety potential value corresponding to the acceptable free alkalinity of the product is available, obtainable from historical data. The system uses a subtractor module to calculate the difference between the current potential value and the standard safety potential value, comparing this difference to a tolerance range, where the tolerance threshold is -5 to +5. If the difference exceeds the maximum value of the tolerance range, it indicates that the current free alkalinity of the product is too low, suggesting a risk of product degradation. Directly extract the basic parameters of the target molar flow ratio currently in use. For example, the basic parameters of the target molar flow ratio are... Add a fixed, small increment value to it, for example, the increment value is 1. Thus, the basic parameters for the new target molar flow ratio are obtained as follows: Subsequently, The new target molar flow ratio is directly overwritten into the calculation of the theoretical alkali volume in Example 1. Thus, during the next control cycle, the system will increase the frequency of the alkali feed pump's inverter to pump in slightly more alkali; conversely, if the difference is less than the minimum tolerance range, it indicates that the free alkalinity is too high, resulting in raw material waste. Subtracting the corresponding step increment value from the basic parameters yields the new basic parameters for the target molar flow ratio. If the difference is within the tolerance range, the current product quality is determined to be in the steady-state qualified range, and the PLC does not perform step correction, maintaining the current target molar flow ratio unchanged. Through the above method, the system effectively solves the long-term static cumulative error and completes the closed loop of the entire adaptive control scheme.

[0041] like Figure 3 As shown, in existing technologies, after thermal fluctuations, due to increased side reactions and a lack of system feedback regulation, the concentration experiences a sustained decline and drastic fluctuations, remaining below the acceptable range for an extended period. This technical solution clearly demonstrates three stages: first, an instantaneous dilution stage caused by water injection to suppress hot spots, where the concentration briefly drops to around 9.5%; followed by a recovery and compensation stage, where the concentration curve steadily recovers due to reduced discharge frequency and the addition of 3% raw material feed; finally, it enters a steady-state range, with the concentration returning to near the target value.

Claims

1. An adaptive control method for disinfectant production, characterized in that, include: S101: Real-time acquisition of gas pressure data in the feed pipeline of raw material gas; S201: Perform time differential calculation on the air pressure data to obtain the real-time air pressure change derivative; Set a warning derivative threshold that characterizes the upper limit of normal process pressure fluctuation; S202: Determine whether the real-time pressure change derivative is greater than the warning derivative threshold. If the determination result is yes, the response is to detect the risk of local thermal runaway and perform instantaneous suppression operation: open the high-speed shut-off valve connected to the main alkali feed channel, and inject low-temperature process water directly into the main alkali feed channel through the high-pressure nozzle until the pressure change derivative is lower than the warning derivative threshold. The amount of low-temperature process water injected is proportional to the difference between the real-time pressure change derivative and the warning derivative threshold.

2. The adaptive control method for disinfectant production according to claim 1, characterized in that, Methods for setting the early warning derivative threshold include: Under stable system operation, continuously collect pressure change derivative data sequences; calculate the mean and standard deviation of the data sequences; and set the warning derivative threshold to the mean and standard deviation of the data sequences. The sum of two standard deviations.

3. The adaptive control method for disinfectant production according to claim 1, characterized in that, The calculation method for the amount of cryogenic process water injected is as follows: The target injection flow rate is obtained by multiplying the difference between the real-time air pressure change derivative and the early warning derivative threshold by a preset volume compensation coefficient.

4. The adaptive control method for disinfectant production according to claim 3, characterized in that, Methods for determining the volume compensation coefficient include: The excess heat released by the reaction due to the unit pressure increase and the heat absorbed by the unit volume of low-temperature process water are calculated in advance, and the ratio of the excess heat released by the reaction to the absorbed heat is used as the volume compensation coefficient.

5. The adaptive control method for disinfectant production according to claim 1, characterized in that, After the transient suppression operation is completed, a concentration recovery operation is also performed, including: Once the real-time pressure change derivative is detected to fall below the warning derivative threshold, the injection of cryogenic process water is stopped. The total amount of cryogenic process water injected during the instantaneous suppression operation is integrated and accumulated. In the subsequent stable production stage, the basic feed rates of raw material gas and alkali solution are increased by superimposing according to the preset compensation ratio until the volume of the supplemented reaction products is offset by the total amount of injected cryogenic process water.

6. The adaptive control method for disinfectant production according to claim 5, characterized in that, The concentration recovery operation also includes: while starting to increase the feed rate, reducing the operating frequency of the finished product discharge pump at the bottom of the reactor to extend the residence time of the mixture in the reactor.

7. The adaptive control method for disinfectant production according to claim 1, characterized in that, Implement feedforward control of basic material proportioning, including: Real-time acquisition of the mass flow rate of the raw gas; Based on the set target molar flow ratio and the molar mass of the raw gas, the corresponding theoretical alkali feed rate is calculated, and the operating frequency of the alkali feed pump is controlled so that the actual alkali flow rate reaches the theoretical alkali feed rate.

8. The adaptive control method for disinfectant production according to claim 7, characterized in that, Basic material proportioning feedforward control also includes: The theoretical total heating power is obtained by multiplying the collected raw gas mass flow rate by the enthalpy constant. The theoretical cooling water requirement is calculated based on the total theoretical heat generation power, and the opening of the cooling water inlet valve flowing through the external cooling jacket of the reactor is adjusted.

9. The adaptive control method for disinfectant production according to claim 1, characterized in that, Also includes: The main reaction temperature and the oxidation-reduction potential at the product outlet in the reactor are controlled by PID closed-loop control: if the main reaction temperature exceeds the safety threshold, the opening of the cooling water inlet valve is increased; if the oxidation-reduction potential deviates from the set range, the alkaline feed rate is finely adjusted to ensure that the free alkalinity at the reaction endpoint is qualified.

10. The adaptive control method for disinfectant production according to claim 1, characterized in that, The method also includes an adaptive optimization step: Collect the actual effective chlorine concentration of the final product; As the actual effective chlorine concentration returns to the qualified range, the system instructs the discharge pump frequency converter to resume normal operation frequency to maintain production capacity; If the system detects that the actual effective chlorine concentration is within the acceptable range but there is still a slight static deviation from the set target value, the target molar flow ratio will be adaptively adjusted to eliminate the static deviation.

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