A method for removing chlorine in the preparation of glycidyl esters

Abstract

This invention relates to the field of waste gas purification technology and discloses a method for dechlorination purification in the preparation of glycidyl esters, comprising: firstly, calculating the target absorbent flow rate based on the gas volume flow rate, chlorine concentration, and temperature; calculating the liquid film tearing stress by combining the absorbent flow rate change and liquid film thickness; calculating the ultrasonic wave dispersion power from the liquid film tearing stress; calculating the aerosol volume formation rate based on the ultrasonic wave dispersion power; calculating the reference electrostatic field strength using the aerosol volume formation rate and gas dynamic viscosity; calculating the dielectric constant perturbation by combining the gas dielectric constant; calculating the breakdown modulation pulse voltage based on the dielectric constant perturbation; and finally, calculating the absorbent actuation delay time and the electrostatic pulse actuation delay time by combining the gas volume flow rate and the spatial height distance of each action zone, and outputting the execution command synchronously with a delay.

Description

Technical Field

[0001] This invention relates to the field of waste gas purification technology, specifically a method for dechlorination and purification in the preparation of glycidyl esters. Background Technology

[0002] In the preparation process of glycidyl esters, the vacuum removal stage typically emits waste gas containing hydrogen chloride and volatile organic chlorides. Existing technologies mostly employ static spray absorption with a fixed flow rate for gas-phase purification. However, in actual production, the transient gas flow rate and chlorine concentration fluctuate. A fixed-flow-rate spray liquid cannot match real-time changes in the gas-phase load, easily leading to uneven gas-liquid contact reactions and causing some chlorine-containing gas to escape. To address the load fluctuation problem, some existing purification systems attempt to dynamically adjust the spray flow rate of the absorbent liquid. However, under high-frequency adjustment conditions, the rapid change in spray flow rate generates fluid inertial shear force on the surface of the absorber packing. This shear force disrupts the liquid distribution on the packing surface, tears the local liquid film, and generates a channeling effect that allows gas to penetrate, thus reducing the absorption effect. To suppress liquid film tearing, some purification schemes introduce ultrasonic dispersion equipment to apply acoustic radiation pressure to the liquid surface. However, under the influence of the acoustic field, the high-frequency cavitation effect of ultrasound inevitably strips secondary chlorine-containing aerosol mist from the liquid film surface. These tiny droplets cannot be blocked by conventional physical baffle demisters. To intercept these secondary aerosol mists, some systems add electrostatic field devices at the top of the tower. However, due to the transient changes in the volume percentage of mist in the mixed gas flow, the equivalent dielectric constant of the mixed gas becomes distorted. Traditional electrostatic demisters typically use a fixed high-voltage output; when the dielectric constant of the medium changes abruptly, arcing and breakdown can easily occur between the electrostatic plates, leading to discharge failure. Furthermore, the spraying, ultrasonic, and electrostatic mechanisms in existing purification systems are mostly independently controlled, lacking a synchronous delay mechanism based on fluid spatial motion, resulting in spatial phase misalignment during the execution of control commands.

[0003] Therefore, a dechlorination and purification method is needed in the preparation of glycidyl esters to maintain stable gas-liquid absorption under variable load conditions and ensure the safe and coordinated operation of the purification system. Summary of the Invention

[0004] This invention provides a method for dechlorination and purification in the preparation of glycidyl esters, which helps to solve the problems mentioned in the background art.

[0005] This invention provides the following technical solution: a method for dechlorination and purification in the preparation of glycidyl esters, comprising: Calculate the target absorbent flow rate based on the gas volume flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature. The liquid film tearing stress is calculated by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness. The ultrasonic dispersion power is calculated from the tear stress of the liquid film and the speed of sound propagation in the liquid; The aerosol volume formation rate was calculated based on the ultrasonic dispersion power and the surface tension of the absorbing liquid. The reference electrostatic field strength is calculated using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient. The dielectric constant perturbation is calculated by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant. The breakdown modulation pulse voltage is calculated based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant. Based on the gas volume flow rate and the spatial height distance between each action zone, the actuation delay time of the absorbent liquid and the actuation delay time of the electrostatic pulse are calculated respectively, and the execution command is output synchronously by the system's bottom-level controller after a delay.

[0006] Optionally, the step of calculating the target absorbent flow rate based on the gas volumetric flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature includes: Hardware sensors are arranged in the gas-liquid absorption tower system. A gas flow meter, a chlorine concentration sensor and a gas temperature sensor are installed at the exhaust gas inlet. An optical liquid film thickness sensor is installed in the packing area of ​​the gas-liquid absorption tower. A microwave resonant dielectric constant sensor is installed in the pre-electrostatic precipitator area at the top of the tower. The gas volume flow rate collected by the gas flow meter is obtained, the inlet chlorine concentration collected by the chlorine concentration sensor is obtained, and the gas temperature collected by the gas temperature sensor is obtained. Obtain the standard absorption density constant and set the reference temperature; Multiply the gas volume flow rate by the concentration of chlorine-containing substances in the inlet chlorine gas to obtain the absolute mass flow rate of chlorine gas; Calculate the difference between the gas temperature and the reference temperature; Calculate the ratio of the difference to the reference temperature; Calculate the value of the exponential function with the natural constant as the base and the ratio as the exponent; Calculate the ratio of the absolute mass flow rate of chlorine gas to the standard absorbed density constant; The target absorbent flow rate is obtained by multiplying the ratio of the absolute mass flow rate of chlorine gas to the standard absorption density constant and the value of the exponential function.

[0007] Optionally, the step of calculating the liquid film tear stress by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness includes: Obtain the absorbent flow rate of the previous sampling period stored in the system history register, obtain the absorbent density constant, obtain the liquid film thickness collected by the optical liquid film thickness sensor, obtain the cross-sectional area of ​​the gas-liquid absorption tower, and set the sampling time interval. The change in absorbent flow rate is obtained by subtracting the target absorbent flow rate from the absorbent flow rate of the previous sampling period. Multiply the cross-sectional area of ​​the gas-liquid absorption tower by the sampling time interval to obtain the first product; The second product is obtained by multiplying the absorbent density constant, the liquid film thickness, and the absorbent flow rate change in sequence. Dividing the second product by the first product yields the liquid film tearing stress.

[0008] Optionally, the calculation of ultrasonic dispersion power from the liquid film tearing stress and the speed of sound propagation in the liquid includes: To obtain the speed at which sound travels through a liquid; Multiplying the liquid film tearing stress by the speed of sound propagation in the liquid yields a third product; Divide the third product by the value 2 to obtain the ultrasonic intensity. The ultrasonic dispersion power is obtained by multiplying the ultrasonic intensity by the cross-sectional area of ​​the gas-liquid absorption tower.

[0009] Optionally, the calculation of aerosol volume formation rate based on the ultrasonic dispersion power and the surface tension of the absorbing liquid includes: Obtain the cavitation efficiency constant, the typical diameter of the cavitation droplet, and the surface tension of the absorbent liquid; The fourth product is obtained by multiplying the ultrasonic dispersion power, the cavitation efficiency constant, and the typical diameter of the cavitation droplet in sequence. Multiplying the value 6 by the surface tension of the absorbent liquid yields the fifth product; Dividing the fourth product by the fifth product yields the aerosol volume formation rate.

[0010] Optionally, the calculation of the reference electrostatic field strength using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient includes: Obtain the gas dynamic viscosity and the pre-charge coefficient; The aerosol volume formation rate, the numerical value 3, the pi constant, and the gas dynamic viscosity are multiplied sequentially to obtain the sixth product; Multiplying the cross-sectional area of ​​the gas-liquid absorption tower by the pre-charge coefficient yields the seventh product; Dividing the sixth product by the seventh product yields the reference electrostatic field strength.

[0011] Optionally, the step of calculating the dielectric constant perturbation by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant includes: Obtain the gas dielectric constant collected by the dielectric constant sensor, and obtain the relative dielectric constant of the absorption liquid; The gas volumetric flow rate is added to the aerosol volumetric generation rate to obtain a first sum. Divide the aerosol volume generation rate by the first sum to obtain the aerosol volume perturbation rate. The first difference is obtained by subtracting the relative permittivity of the absorbent from the permittivity of the gas. Multiply the gas dielectric constant by the value 2, and add the product to the relative dielectric constant of the absorbent liquid to obtain the second sum. Divide the first difference by the second sum to obtain the first quotient; Multiply the value 3, the aerosol volume perturbation rate, and the first quotient in sequence to obtain the eighth product; Add the value 1 to the eighth product to obtain the third sum; Multiplying the gas dielectric constant by the third sum yields the effective dielectric constant of the mixed gas and liquid; The dielectric constant perturbation is obtained by subtracting the effective dielectric constant of the mixed gas and liquid from the dielectric constant of the gas.

[0012] Optionally, the step of calculating the breakdown-resistant modulation pulse voltage based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant includes: Obtain the electrode spacing; Divide the dielectric constant perturbation by the gas dielectric constant to obtain a second quotient. Take the negative of the second quotient as the exponent; Calculate the value of the second exponential function with the natural constant as the base; The reference electrostatic field strength, the electrode spacing, and the second exponential function value are multiplied sequentially to obtain the breakdown-resistant modulation pulse voltage.

[0013] Optionally, the absorption liquid actuation delay time and electrostatic pulse actuation delay time are calculated by combining the gas volume flow rate and the spatial height distance between each action zone, and the execution command is output synchronously by the system's underlying controller after a delay, including: Obtain the spatial height distance from the air inlet of the gas-liquid absorption tower to the packing area, obtain the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and obtain the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic precipitator. Divide the gas volume flow rate by the cross-sectional area of ​​the gas-liquid absorption tower to obtain the gas apparent flow rate; Divide the spatial height distance from the gas inlet to the packing area of ​​the gas-liquid absorption tower by the apparent gas velocity to obtain the absorption liquid actuation delay time. The fourth sum is obtained by adding the spatial height distance from the air inlet of the gas-liquid absorption tower to the packing area, the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic demister. Divide the fourth sum by the apparent gas flow rate to obtain the electrostatic pulse actuation delay time. After waiting for the corresponding absorption liquid actuation delay time and the electrostatic pulse actuation delay time, the system's underlying controller synchronously outputs and executes commands to regulate the target absorption liquid flow rate, the ultrasonic dispersion power, and the anti-breakdown modulation pulse voltage.

[0014] The present invention has the following beneficial effects: 1. By acquiring the gas volumetric flow rate, inlet chlorine concentration, and gas temperature during the dechlorination and purification stage in glycidyl ester preparation, this scheme calculates the target absorbent flow rate to adapt to changes in inlet operating conditions, specifically addressing the environment of transient load fluctuations in exhaust gas. Since adjusting the target absorbent flow rate will generate liquid film tearing stress in the packing area of ​​the gas-liquid absorption tower, causing uneven gas-liquid distribution, the scheme calculates the corresponding ultrasonic dispersion power to offset this. For the specific operating condition where ultrasonic waves induce aerosols, causing abrupt changes in the mixed gas flow space medium, the scheme calculates the aerosol volume generation rate and the resulting dielectric constant perturbation, and accordingly calculates the anti-breakdown modulation pulse voltage to reduce the risk of arc breakdown due to changes in the gas dielectric constant. Furthermore, the scheme comprehensively considers the gas volumetric flow rate and the spatial height distance between each action zone to calculate the absorbent actuation delay time and the electrostatic pulse actuation delay time, and outputs the execution command synchronously with a delay. This solution can maintain the stability of the gas-liquid absorption state under fluctuating intake conditions, suppress exhaust gas penetration caused by liquid film tearing, maintain the continuous operation of the electrostatic demister when the space medium changes abruptly, and achieve coordinated control of the actions of each actuator based on the fluid motion phase.

[0015] 2. By distributing gas flow meters, chlorine concentration sensors, and gas temperature sensors within the gas-liquid absorption tower system to obtain multi-dimensional gas phase parameters, and combining the inlet chlorine concentration and gas volume flow rate, the absolute mass flow rate of chlorine flowing into the system is calculated in advance. Then, an exponential function based on the deviation of gas temperature from the reference temperature is introduced as a thermodynamic temperature deviation compensation mechanism. The absolute mass flow rate of chlorine is correlated with the standard absorption density constant to determine the target absorbent flow rate. This method can sensitively detect the material load fluctuations generated by the exhaust gas under transient exhaust conditions, avoiding the uneven local gas-liquid contact reaction caused by conventional fixed flow rate spraying. With the help of dynamic compensation and adjustment of thermodynamic state, the amount of absorbent added is always matched with the gas phase load under varying inlet conditions, maintaining the dynamic equilibrium state of the gas-liquid reaction process and reducing the escape of chlorine-containing gas.

[0016] 3. By extracting the target absorbent flow rate calculated within the current cycle and the absorbent flow rate stored in the system's historical register from the previous sampling cycle, the change in absorbent flow rate is obtained. Combined with the absorbent density constant, the cross-sectional area of ​​the gas-liquid absorption tower, the sampling time interval, and the liquid film thickness parameters collected by the optical liquid film thickness sensor, the macroscopic physical inertial force generated during fluid acceleration is mapped onto the packing surface, thereby quantitatively calculating the dynamic liquid film tearing stress. This step establishes a direct physical link between the dynamic adjustment of the absorbent spray flow rate and the stress state of the liquid film on the packing surface. It can objectively quantify the shear force generated by the fluid under the condition of rapid flow change, providing an accurate stress assessment benchmark for subsequently suppressing the shear force from damaging the liquid distribution state on the packing surface. This is beneficial for predicting and responding to the channeling risk of local liquid film tearing leading to gas phase penetration, and ensuring the effective contact area between the gas and liquid phases in the packing area.

[0017] 4. By introducing the principle of acoustic impedance matching, a mapping relationship is established between the liquid film tearing stress obtained from previous quantification and the speed of sound propagation in the liquid. The ultrasonic intensity used to counteract the mechanical stress of the surface fluid is calculated, and combined with the cross-sectional area of ​​the gas-liquid absorption tower, it is converted into the ultrasonic dispersion power required for the output of the ultrasonic transducer in the drive system. This treatment method uses the acoustic radiation pressure in nonlinear acoustics to counteract the physical shearing damage caused by the transient flow regulation of the absorbent liquid, so that the control system can output sound field energy that matches the magnitude of the destructive force. Without changing the macroscopic spray ratio of the fluid, it adaptively alleviates the tearing effect of the fluid inertial shear force on the liquid film, maintains the integrity and stability of the liquid film morphology on the packing surface, and ensures the uniformity of the absorbent liquid distribution in the packing area, thereby blocking the path of the exhaust gas to directly penetrate without reaction.

[0018] 5. By adhering to the conservation law of energy conversion to liquid surface free energy, the calculated ultrasonic dispersion power is integrated with the cavitation efficiency constant and typical diameter of cavitation droplets obtained within the system. Under the physical constraint of the surface tension of the absorbing liquid, the aerosol volume generation rate caused by microscopic cavitation induced by the injection of ultrasonic high-frequency mechanical energy is deduced and calculated. This processing logic takes into account the phase transition evolution law that accompanies the intervention of acoustic radiation pressure. It can objectively and quantitatively assess the level of secondary chlorine-containing aerosol particles physically atomized and stripped from the liquid film surface. It transforms the small-scale secondary pollutant load generated during the operation of ultrasonic equipment into measurable spatial volume parameters, providing clear source term data support for the subsequent implementation of electrostatic field interception in the system, and avoiding the deterioration of system exhaust emission indicators due to neglecting secondary aerosols.

[0019] 6. By employing the physical mechanism of balancing Stokes fluid viscous resistance and Coulomb force, the aerosol volume generation rate obtained from previous calculations is used as the load input. Integrating gas dynamic viscosity, the mathematical constant of pi, the cross-sectional area of ​​the gas-liquid absorption tower, and the pre-charge coefficient calibrated by the corona release array, the baseline electrostatic field strength required to drive the lateral drift and condensation of secondary micro-droplets is calculated. This feature combines the mechanical resistance of aerosols in the flow field with the electromagnetic driving force generated by the electrostatic field, constructing a baseline threshold model for capturing ultrafine particles. This allows the system to set the initial electrostatic demisting intensity, effectively compensating for the insufficient interception capability of conventional physical baffle demisters for microscale secondary aerosols generated by ultrasonic cavitation, ensuring that aerosol mists containing harmful substances are effectively condensed and intercepted by the high-voltage electrostatic field.

[0020] 7. By correlating the gas volumetric flow rate with the dynamically generated aerosol volumetric generation rate to define the volumetric perturbation ratio of micro-droplets in the mixing space, and introducing the Maxwell-Garnett equivalent mixing medium model, the effective dielectric constant of the mixed gas-liquid mixture, including liquid-phase micro-mist and continuous gas phase, is solved using the relative permittivity of the absorbent liquid and the gas dielectric constant collected by the dielectric constant sensor. This allows for the calculation of the dielectric constant perturbation relative to the pure gas phase environment. This process considers the distortion effect of transient changes in the volume ratio of micro-mist in the mixed gas flow on the overall spatial electromagnetic properties, transforming the complex spatial multiphase fluid medium abrupt change phenomenon into quantifiable electrical characteristic parameters. This enables the control system to detect fluctuations in the dielectric properties of the gas-liquid mixture in advance, providing a sensitive perturbation measurement index for subsequent adjustment of the high-voltage static electrode plate's operating parameters.

[0021] 8. By comparing the obtained dielectric constant perturbation with the gas dielectric constant to construct a perturbation ratio, a negative exponential decay adjustment term based on this perturbation ratio is constructed. This adaptive breakdown safety modulation parameter is then multiplied by the previously calculated reference electrostatic field strength and the inherent electrode spacing of the equipment to calculate the breakdown modulation pulse voltage. This adjustment mechanism actively weakens the output voltage level when the dielectric constant of the dielectric deteriorates due to perturbation, thus addressing the risk of decreased insulation characteristics caused by the transient generation of secondary aerosol mist. It improves the limitations faced by traditional electrostatic demisting equipment using fixed high-voltage output, reduces the probability of arc breakdown and discharge failure between plates, ensures that the electrostatic field can maintain continuous and stable demisting interception function even when the gas phase conditions change abruptly, and extends the safe operation cycle of electrical equipment.

[0022] 9. By converting the gas volumetric flow rate obtained by the system into the apparent gas velocity, and comprehensively considering the spatial height distance parameters from the gas-liquid absorption tower inlet to the packing area, from the packing area to the ultrasonic action area, and from the ultrasonic action area to the electrostatic precipitator, the actuation delay time of the absorbent liquid issued to the liquid spraying actuator and the actuation delay time of the electrostatic pulse issued to the electrostatic pulse control mechanism are calculated according to the kinematic laws, and the delay is synchronously output by the system's bottom controller. This strategy establishes a timing compensation and collaborative control mechanism based on the phase of fluid spatial motion, eliminating the potential for action disconnection when the actuators at each level operate independently. This allows the three physical control actions—spray liquid volume adjustment, sound field radiation cancellation, and electric field pulse modulation—to be triggered when the same fluctuating chlorine-containing mixed gas flows to the corresponding physical height, realizing spatial linkage control of the entire process. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the basic process of the present invention.

[0024] Figure 2 This is a schematic diagram of the sensor arrangement and spatial relationship of the working area in this invention.

[0025] Figure 3 This is a schematic diagram showing the relationship between liquid film tearing stress, ultrasonic dispersion power, and aerosol formation in this invention.

[0026] Figure 4 This is a schematic diagram illustrating the relationship between dielectric constant perturbation, breakdown prevention modulation, and actuation delay synchronization in this invention. Detailed Implementation

[0027] 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.

[0028] Example 1, refer to Figure 1 A method for dechlorination and purification in the preparation of glycidyl esters, comprising: Calculate the target absorbent flow rate based on the gas volume flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature. The liquid film tearing stress is calculated by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness. The ultrasonic dispersion power is calculated from the tear stress of the liquid film and the speed of sound propagation in the liquid; The aerosol volume formation rate was calculated based on the ultrasonic dispersion power and the surface tension of the absorbing liquid. The reference electrostatic field strength is calculated using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient. The dielectric constant perturbation is calculated by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant. The breakdown modulation pulse voltage is calculated based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant. Based on the gas volume flow rate and the spatial height distance between each action zone, the actuation delay time of the absorbent liquid and the actuation delay time of the electrostatic pulse are calculated respectively, and the execution command is output synchronously by the system's bottom-level controller after a delay.

[0029] Reference Figure 2 , Figure 2 The spatial layout of the exhaust gas inlet, packing area, ultrasonic action area, and electrostatic precipitator pre-positioning area is shown, and the corresponding sensor acquisition positions are marked.

[0030] The calculation of the target absorbent flow rate based on the gas volumetric flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature includes: The following hardware sensors are installed in the gas-liquid absorption tower system: a gas flow meter, a chlorine concentration sensor, and a gas temperature sensor are installed at the exhaust gas inlet; an optical liquid film thickness sensor is installed in the packing area of ​​the gas-liquid absorption tower; and a microwave resonant dielectric constant sensor is installed in the pre-electrostatic precipitator area at the top of the tower. To address the initial problem of uneven absorption caused by transient gas fluctuations, at the beginning of the steps, the gas volumetric flow rate collected by the gas flow meter, the inlet chlorine concentration collected by the chlorine concentration sensor, and the gas temperature collected by the gas temperature sensor are obtained; the standard absorption density constant is obtained, and the reference temperature is set. Based on the sensor data for the current period, the absolute mass flow rate of chlorine gas flowing into the absorption tower is first calculated. The calculation steps are as follows: Multiply the gas volume flow rate by the concentration of chlorine-containing substances in the inlet chlorine gas to obtain the absolute mass flow rate of chlorine gas; After obtaining the absolute mass flow rate, the target absorbent flow rate required under the current fluctuation state is calculated by combining the chemical absorption capacity constant of the selected absorbent and the real-time thermodynamic temperature deviation compensation. The calculation steps are as follows: Calculate the difference between the gas temperature and the reference temperature; calculate the ratio of the difference to the reference temperature; calculate the exponential function value with the natural constant as the base and the ratio as the exponent; calculate the ratio of the absolute mass flow rate of chlorine gas to the standard absorption density constant; multiply the ratio of the absolute mass flow rate of chlorine gas to the standard absorption density constant and the exponential function value to obtain the target absorbent flow rate.

[0031] By distributing gas flow meters, chlorine concentration sensors, and gas temperature sensors within the gas-liquid absorption tower system to obtain multidimensional gas phase parameters, and combining the inlet chlorine concentration and gas volume flow rate, the absolute mass flow rate of chlorine entering the system is calculated in advance. Then, an exponential function based on the deviation of gas temperature from a reference temperature is introduced as a thermodynamic temperature deviation compensation mechanism. The absolute mass flow rate of chlorine is correlated with the standard absorption density constant to determine the target absorbent flow rate. This method can sensitively detect the material load fluctuations generated by the exhaust gas under transient exhaust conditions, avoiding the uneven local gas-liquid contact reaction caused by conventional fixed flow rate spraying. With the help of dynamic compensation and adjustment of thermodynamic state, the amount of absorbent added is always matched with the gas phase load under varying inlet conditions, maintaining the dynamic equilibrium state of the gas-liquid reaction process and reducing the escape of chlorine-containing gas.

[0032] The calculation of liquid film tear stress by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness includes: To quantify the risk of "channeling" tearing caused by sudden changes in flow rate, at the beginning of the step, the absorbent flow rate of the previous sampling period stored in the system history register is obtained, the absorbent density constant is obtained, the liquid film thickness collected by the optical liquid film thickness sensor is obtained, the cross-sectional area of ​​the gas-liquid absorption tower is obtained, and the sampling time interval is set. The system extracts the target absorbent flow rate calculated in the current cycle and the target absorbent flow rate in the previous cycle, calculates the difference between the two to determine the change in absorbent flow rate, and the calculation steps are as follows: The change in absorbent flow rate is obtained by subtracting the target absorbent flow rate from the absorbent flow rate of the previous sampling period. Subsequently, taking into account the macroscopic physical inertial force generated during fluid acceleration, the liquid film tearing stress acting on the packing surface is calculated. The calculation steps are as follows: Multiply the cross-sectional area of ​​the gas-liquid absorption tower by the sampling time interval to obtain a first product; multiply the absorbent density constant, the liquid film thickness, and the absorbent flow rate change in sequence to obtain a second product; divide the second product by the first product to obtain the liquid film tear stress.

[0033] By extracting the target absorbent flow rate calculated within the current system cycle and the absorbent flow rate stored in the system's historical register from the previous sampling cycle, the change in absorbent flow rate is obtained. Combined with the absorbent density constant, the cross-sectional area of ​​the gas-liquid absorption tower, the sampling time interval, and the liquid film thickness parameters collected by the optical liquid film thickness sensor, the macroscopic physical inertial force generated during fluid acceleration is mapped onto the packing surface, thereby quantitatively calculating the dynamic liquid film tearing stress. This step establishes a direct physical link between the dynamic adjustment of the absorbent spray flow rate and the stress state of the liquid film on the packing surface. It can objectively quantify the shear force generated by the fluid under the condition of rapid flow change, providing an accurate stress assessment benchmark for subsequently suppressing the shear force from damaging the liquid distribution state on the packing surface. This is beneficial for predicting and responding to the channeling risk of local liquid film tearing leading to gas phase penetration, and ensuring the effective contact area between the gas and liquid phases in the packing area.

[0034] The calculation of ultrasonic dispersion power from the liquid film tearing stress and the speed of sound propagation in the liquid includes: To accurately counteract the tearing stress of the liquid film and prevent channeling, the speed of sound propagation in the liquid is obtained at the beginning of the step.

[0035] Based on the principle of acoustic impedance matching, the ultrasonic intensity required to just offset the mechanical stress is first calculated. The calculation steps are as follows: Multiply the liquid film tearing stress by the sound propagation speed in the liquid to obtain a third product; divide the third product by the value 2 to obtain the ultrasonic intensity. After obtaining the ultrasonic intensity of the areal density, it is converted into the total output power required to drive the ultrasonic transducer. The calculation steps are as follows: The ultrasonic dispersion power is obtained by multiplying the ultrasonic intensity by the cross-sectional area of ​​the gas-liquid absorption tower.

[0036] By introducing the principle of acoustic impedance matching, a mapping relationship is established between the liquid film tearing stress obtained from previous quantification and the speed of sound propagation in the liquid. The ultrasonic intensity used to counteract the mechanical stress of the surface fluid is calculated, and combined with the cross-sectional area of ​​the gas-liquid absorption tower, it is converted into the ultrasonic dispersion power required for the output of the ultrasonic transducer in the drive system. This treatment method uses the acoustic radiation pressure in nonlinear acoustics to counteract the physical shearing damage caused by the transient flow regulation of the absorbent liquid, enabling the control system to output sound field energy that matches the magnitude of the destructive force. Without changing the macroscopic spray ratio of the fluid, it adaptively alleviates the tearing effect of the fluid inertial shear force on the liquid film, maintains the integrity and stability of the liquid film morphology on the packing surface, and ensures the uniformity of the absorbent liquid distribution in the packing area, thereby blocking the path of the exhaust gas to directly penetrate without reaction.

[0037] The calculation of aerosol volume formation rate based on the ultrasonic dispersion power and the surface tension of the absorbing liquid includes: Because the injection of high-frequency mechanical energy from ultrasound induces microscopic cavitation to generate aerosols, at the beginning of the step, the cavitation efficiency constant, the typical diameter of the cavitation droplets, and the surface tension of the absorbent liquid are obtained. Based on the law of conservation of energy conversion to liquid surface free energy, the volume fraction of this secondary micro-pollutant is calculated. The calculation steps are as follows: The ultrasonic dispersion power, the cavitation efficiency constant, and the typical diameter of the cavitation droplet are multiplied sequentially to obtain a fourth product; the value 6 is multiplied by the surface tension of the absorbent liquid to obtain a fifth product; the fourth product is divided by the fifth product to obtain the aerosol volume formation rate.

[0038] Reference Figure 3 , Figure 3 The correspondence between absorbent flow rate parameters, liquid film state parameters, and acoustic field and aerosol parameters is shown to understand the calculation chain from liquid film tearing stress to aerosol volume formation rate.

[0039] By adhering to the conservation law of energy conversion to liquid surface free energy, the calculated ultrasonic dispersion power is integrated with the cavitation efficiency constant and typical diameter of cavitation droplets obtained within the system. Under the physical constraint of the surface tension of the absorbing liquid, the aerosol volume generation rate caused by microscopic cavitation induced by the injection of ultrasonic high-frequency mechanical energy is deduced and calculated. This processing logic takes into account the phase transition evolution law that accompanies the intervention of acoustic radiation pressure, and can objectively and quantitatively assess the level of secondary chlorine-containing aerosol particles physically atomized and stripped from the liquid film surface. It transforms the small-scale secondary pollutant load generated during the operation of ultrasonic equipment into measurable spatial volume parameters, providing clear source term data support for the subsequent implementation of electrostatic field interception in the system, and avoiding the deterioration of system exhaust emission indicators due to neglecting secondary aerosols.

[0040] The calculation of the reference electrostatic field strength using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient includes: To intercept aerosol mist, the gas dynamic viscosity and pre-charge coefficient are obtained at the beginning of the step. A high-voltage electrostatic field is used to drive the droplets to drift laterally and coalesce. Based on the balance equation of Stokes fluid viscous drag and Coulomb force, the required reference electrostatic field strength is calculated. The calculation steps are as follows: The aerosol volumetric generation rate, the numerical value 3, the pi constant, and the gas dynamic viscosity are multiplied sequentially to obtain the sixth product; the cross-sectional area of ​​the gas-liquid absorption tower is multiplied by the pre-charge coefficient to obtain the seventh product; the sixth product is divided by the seventh product to obtain the reference electrostatic field strength.

[0041] By employing a physical mechanism that balances Stokes fluid viscous resistance and Coulomb force, the aerosol volume generation rate obtained from previous calculations is used as the load input. Integrating gas dynamic viscosity, the mathematical constant of pi, the cross-sectional area of ​​the gas-liquid absorption tower, and the pre-charge coefficient calibrated by the corona release array, a baseline electrostatic field strength necessary to drive the lateral drift and condensation of secondary micro-droplets is calculated. This feature combines the mechanical resistance of aerosols in the flow field with the electromagnetic driving force generated by the electrostatic field, constructing a baseline threshold model for capturing ultrafine particles. This allows the system to set the initial electrostatic demisting intensity, effectively compensating for the insufficient interception capability of conventional physical baffle demisters for microscale secondary aerosols generated by ultrasonic cavitation, ensuring that aerosol mists containing harmful substances are effectively condensed and intercepted by the high-voltage electrostatic field.

[0042] The calculation of the dielectric constant perturbation by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant includes: As transient aerosols are introduced, the spatial medium undergoes abrupt changes. At the beginning of the step, the gas dielectric constant is acquired by a dielectric constant sensor, and the relative dielectric constant of the absorbent liquid is acquired. First, calculate the volume ratio of aerosols in the mixing space based on the gas-liquid flow rate relationship. The calculation steps are as follows: The gas volume flow rate is added to the aerosol volume formation rate to obtain a first sum; the aerosol volume formation rate is divided by the first sum to obtain the aerosol volume perturbation rate. Subsequently, the overall macroscopic effective dielectric constant was calculated using the Maxwell-Garnett equivalent hybrid dielectric model. The calculation steps are as follows: Subtracting the relative permittivity of the absorbent liquid from the permittivity of the gas yields a first difference; multiplying the gas permittivity by the value 2 and adding the product to the relative permittivity of the absorbent liquid yields a second sum; dividing the first difference by the second sum yields a first quotient; multiplying the value 3, the aerosol volume perturbation rate, and the first quotient sequentially yields an eighth product; adding the value 1 to the eighth product yields a third sum; multiplying the gas permittivity by the third sum yields the effective permittivity of the gas-liquid mixture. Therefore, the dielectric property distortion displacement caused by a relatively pure gas phase environment is obtained, and the calculation steps are as follows: The dielectric constant perturbation is obtained by subtracting the effective dielectric constant of the mixed gas and liquid from the dielectric constant of the gas.

[0043] By correlating gas volumetric flow rate with the dynamically generated aerosol volumetric generation rate to define the proportion of volumetric perturbations of microdroplets in the mixing space, and introducing the Maxwell-Garnett equivalent mixing medium model, the effective dielectric constant of the mixed gas-liquid mixture, including liquid-phase micro-mist and continuous gas phase, is solved using the relative permittivity of the absorbent liquid and the gas dielectric constant collected by the dielectric constant sensor. This allows for the calculation of the dielectric constant perturbation relative to the pure gas phase environment. This process considers the distortion effect of transient changes in the volume ratio of micro-mist in the mixed gas flow on the overall spatial electromagnetic properties, transforming the complex abrupt changes in the multiphase fluid medium into quantifiable electrical characteristic parameters. This enables the control system to detect fluctuations in the dielectric properties of the gas-liquid mixture in advance, providing a sensitive perturbation metric for subsequent adjustments to the operating parameters of the high-voltage electrostatic electrode plate.

[0044] The calculation of the breakdown-resistant modulation pulse voltage based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant includes: To prevent electrostatic arcing breakdown when the dielectric constant is slightly perturbed, the electrode spacing is obtained at the beginning of the step; A negative exponential decay term based on the perturbation ratio is introduced to adaptively modulate the output voltage corresponding to the theoretical reference field strength to prevent breakdown. The calculation steps are as follows: Divide the dielectric constant perturbation by the gas dielectric constant to obtain a second quotient; take the opposite of the second quotient as the exponent; calculate the second exponential function value with the natural constant as the base; multiply the reference electrostatic field strength, the electrode spacing and the second exponential function value in sequence to obtain the breakdown modulation pulse voltage.

[0045] By comparing the obtained dielectric constant perturbation with the gas dielectric constant to construct a perturbation ratio, a negative exponential decay adjustment term based on this perturbation ratio is constructed. This adaptive breakdown safety modulation parameter is then multiplied by the previously calculated reference electrostatic field strength and the inherent electrode spacing of the equipment to calculate the breakdown prevention modulation pulse voltage. This adjustment mechanism actively weakens the output voltage level when the dielectric constant of the dielectric deteriorates due to perturbation, addressing the risk of decreased insulation characteristics caused by the transient generation of secondary aerosol mist. It improves upon the limitations of traditional electrostatic demisting equipment using fixed high-voltage output, reduces the probability of arc breakdown and discharge failure between plates, ensures that the electrostatic field can maintain continuous and stable demisting interception function even when the gas phase conditions change abruptly, and extends the safe operation cycle of electrical equipment.

[0046] The gas volume flow rate and the spatial height distance between each action zone are considered together to calculate the absorption liquid actuation delay time and the electrostatic pulse actuation delay time, respectively. The system's underlying controller then outputs execution commands with a time delay, including: To ensure that each actuator accurately triggers its action when the same chlorine-containing gas flows to the corresponding height, at the beginning of the step, the spatial height distance from the gas inlet of the gas-liquid absorption tower to the packing area, the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic demister are obtained. First, calculate the apparent flow velocity of the bulk gas. The calculation steps are as follows: Divide the gas volume flow rate by the cross-sectional area of ​​the gas-liquid absorption tower to obtain the gas apparent flow rate; The physical actuation delay buffer time for issuing commands to the liquid spray actuator is calculated to match the time it takes for the gas to reach the packing zone. The calculation steps are as follows: Divide the spatial height distance from the gas inlet to the packing area of ​​the gas-liquid absorption tower by the apparent gas velocity to obtain the absorption liquid actuation delay time. The calculation steps for the physical actuation delay buffer time of the command issued by the electrostatic demisting pulse control mechanism are as follows: The fourth sum is obtained by adding the spatial height distance from the gas inlet of the gas-liquid absorption tower to the packing area, the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic demister; the fourth sum is obtained by dividing the fourth sum by the apparent gas velocity. After waiting for the corresponding absorption liquid actuation delay time and the electrostatic pulse actuation delay time, the system's underlying controller synchronously outputs and executes commands to regulate the target absorption liquid flow rate, the ultrasonic dispersion power, and the anti-breakdown modulation pulse voltage.

[0047] Reference Figure 4 , Figure 4 The corresponding relationships between the medium input parameters, intermediate electrical quantities, electrostatic pulse quantities, and the distances of each action zone are shown to illustrate the correlation between the breakdown modulation pulse voltage and the synchronous output of the actuation delay.

[0048] By converting the gas volumetric flow rate acquired by the system into the apparent gas velocity, and comprehensively considering various spatial height distance parameters from the gas-liquid absorption tower inlet to the packing area, from the packing area to the ultrasonic action area, and from the ultrasonic action area to the electrostatic precipitator, the actuation delay time of the absorbent liquid issued to the liquid spraying actuator and the actuation delay time of the electrostatic pulse issued to the electrostatic pulse control mechanism are calculated according to kinematic laws, and the delay is synchronously output by the system's bottom-level controller. This strategy establishes a timing compensation and collaborative control mechanism based on the phase of fluid spatial motion, eliminating the potential for action disconnection when each level of actuator operates independently. This allows the three physical control actions—spray liquid volume adjustment, sound field radiation cancellation, and electric field pulse modulation—to be triggered when the same fluctuating chlorine-containing mixed gas flows to the corresponding physical height, achieving spatial linkage control of the entire process.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for dechlorination and purification in the preparation of glycidyl esters, characterized in that, include: Calculate the target absorbent flow rate based on the gas volume flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature. The liquid film tearing stress is calculated by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness. The ultrasonic dispersion power is calculated from the tear stress of the liquid film and the speed of sound propagation in the liquid; The aerosol volume formation rate was calculated based on the ultrasonic dispersion power and the surface tension of the absorbing liquid. The reference electrostatic field strength is calculated using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient. The dielectric constant perturbation is calculated by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant. The breakdown modulation pulse voltage is calculated based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant. Based on the gas volume flow rate and the spatial height distance between each action zone, the actuation delay time of the absorbent liquid and the actuation delay time of the electrostatic pulse are calculated respectively, and the execution command is output synchronously by the system's bottom-level controller after a delay.

2. The dechlorination and purification method for the preparation of glycidyl esters according to claim 1, characterized in that, The calculation of the target absorbent flow rate based on the gas volumetric flow rate, the concentration of chlorine-containing substances in the inlet chlorine gas, and the gas temperature includes: Hardware sensors are arranged in the gas-liquid absorption tower system. A gas flow meter, a chlorine concentration sensor and a gas temperature sensor are installed at the exhaust gas inlet. An optical liquid film thickness sensor is installed in the packing area of ​​the gas-liquid absorption tower. A microwave resonant dielectric constant sensor is installed in the pre-electrostatic precipitator area at the top of the tower. The gas volume flow rate collected by the gas flow meter is obtained, the inlet chlorine concentration collected by the chlorine concentration sensor is obtained, and the gas temperature collected by the gas temperature sensor is obtained. Obtain the standard absorption density constant and set the reference temperature; Multiply the gas volume flow rate by the concentration of chlorine-containing substances in the inlet chlorine gas to obtain the absolute mass flow rate of chlorine gas; Calculate the difference between the gas temperature and the reference temperature; Calculate the ratio of the difference to the reference temperature; Calculate the value of the exponential function with the natural constant as the base and the ratio as the exponent; Calculate the ratio of the absolute mass flow rate of chlorine gas to the standard absorbed density constant; The target absorbent flow rate is obtained by multiplying the ratio of the absolute mass flow rate of chlorine gas to the standard absorption density constant and the value of the exponential function.

3. The dechlorination and purification method for the preparation of glycidyl esters according to claim 2, characterized in that, The calculation of liquid film tear stress by combining the target absorbent flow rate, the absorbent flow rate of the previous sampling period, and the measured liquid film thickness includes: Obtain the absorbent flow rate of the previous sampling period stored in the system history register, obtain the absorbent density constant, obtain the liquid film thickness collected by the optical liquid film thickness sensor, obtain the cross-sectional area of ​​the gas-liquid absorption tower, and set the sampling time interval. The change in absorbent flow rate is obtained by subtracting the target absorbent flow rate from the absorbent flow rate of the previous sampling period. Multiply the cross-sectional area of ​​the gas-liquid absorption tower by the sampling time interval to obtain the first product; The second product is obtained by multiplying the absorbent density constant, the liquid film thickness, and the absorbent flow rate change in sequence. Dividing the second product by the first product yields the liquid film tearing stress.

4. The dechlorination and purification method for the preparation of glycidyl esters according to claim 3, characterized in that, The calculation of ultrasonic dispersion power from the liquid film tearing stress and the speed of sound propagation in the liquid includes: To obtain the speed at which sound travels through a liquid; Multiplying the liquid film tearing stress by the speed of sound propagation in the liquid yields a third product; Divide the third product by the value 2 to obtain the ultrasonic intensity. The ultrasonic dispersion power is obtained by multiplying the ultrasonic intensity by the cross-sectional area of ​​the gas-liquid absorption tower.

5. The dechlorination and purification method for the preparation of glycidyl esters according to claim 4, characterized in that, The calculation of aerosol volume formation rate based on the ultrasonic dispersion power and the surface tension of the absorbing liquid includes: Obtain the cavitation efficiency constant, the typical diameter of the cavitation droplet, and the surface tension of the absorbent liquid; The fourth product is obtained by multiplying the ultrasonic dispersion power, the cavitation efficiency constant, and the typical diameter of the cavitation droplet in sequence. Multiplying the value 6 by the surface tension of the absorbent liquid yields the fifth product; Dividing the fourth product by the fifth product yields the aerosol volume formation rate.

6. The dechlorination and purification method for the preparation of glycidyl esters according to claim 5, characterized in that, The calculation of the reference electrostatic field strength using the aerosol volume formation rate, gas dynamic viscosity, and pre-charge coefficient includes: Obtain the gas dynamic viscosity and the pre-charge coefficient; The aerosol volume formation rate, the numerical value 3, the pi constant, and the gas dynamic viscosity are multiplied sequentially to obtain the sixth product; Multiplying the cross-sectional area of ​​the gas-liquid absorption tower by the pre-charge coefficient yields the seventh product; Dividing the sixth product by the seventh product yields the reference electrostatic field strength.

7. The dechlorination and purification method for the preparation of glycidyl esters according to claim 6, characterized in that, The calculation of the dielectric constant perturbation by combining the aerosol volume formation rate, the gas volume flow rate, and the gas dielectric constant includes: Obtain the gas dielectric constant collected by the dielectric constant sensor, and obtain the relative dielectric constant of the absorption liquid; The gas volumetric flow rate is added to the aerosol volumetric generation rate to obtain a first sum. Divide the aerosol volume generation rate by the first sum to obtain the aerosol volume perturbation rate. The first difference is obtained by subtracting the relative permittivity of the absorbent from the permittivity of the gas. Multiply the gas dielectric constant by the value 2, and add the product to the relative dielectric constant of the absorbent liquid to obtain the second sum. Divide the first difference by the second sum to obtain the first quotient; Multiply the value 3, the aerosol volume perturbation rate, and the first quotient in sequence to obtain the eighth product; Add the value 1 to the eighth product to obtain the third sum; Multiplying the gas dielectric constant by the third sum yields the effective dielectric constant of the mixed gas and liquid; The dielectric constant perturbation is obtained by subtracting the effective dielectric constant of the mixed gas and liquid from the dielectric constant of the gas.

8. The dechlorination and purification method for the preparation of glycidyl esters according to claim 7, characterized in that, The calculation of the breakdown-resistant modulation pulse voltage based on the reference electrostatic field strength, the dielectric constant perturbation, and the gas dielectric constant includes: Obtain the electrode spacing; Divide the dielectric constant perturbation by the gas dielectric constant to obtain a second quotient. Take the negative of the second quotient as the exponent; Calculate the value of the second exponential function with the natural constant as the base; The reference electrostatic field strength, the electrode spacing, and the second exponential function value are multiplied sequentially to obtain the breakdown-resistant modulation pulse voltage.

9. The dechlorination and purification method for the preparation of glycidyl esters according to claim 8, characterized in that, The gas volume flow rate and the spatial height distance between each action zone are considered together to calculate the absorption liquid actuation delay time and the electrostatic pulse actuation delay time, respectively. The system's underlying controller then outputs execution commands with a time delay, including: Obtain the spatial height distance from the air inlet of the gas-liquid absorption tower to the packing area, obtain the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and obtain the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic precipitator. Divide the gas volume flow rate by the cross-sectional area of ​​the gas-liquid absorption tower to obtain the gas apparent flow rate; Divide the spatial height distance from the gas inlet to the packing area of ​​the gas-liquid absorption tower by the apparent gas velocity to obtain the absorption liquid actuation delay time. The fourth sum is obtained by adding the spatial height distance from the air inlet of the gas-liquid absorption tower to the packing area, the spatial height distance from the packing area of ​​the gas-liquid absorption tower to the ultrasonic action area, and the spatial height distance from the ultrasonic action area of ​​the gas-liquid absorption tower to the electrostatic demister. Divide the fourth sum by the apparent gas flow rate to obtain the electrostatic pulse actuation delay time. After waiting for the corresponding absorption liquid actuation delay time and the electrostatic pulse actuation delay time, the system's underlying controller synchronously outputs and executes commands to regulate the target absorption liquid flow rate, the ultrasonic dispersion power, and the anti-breakdown modulation pulse voltage.

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