Potassium tert-butoxide production safety regulation and control method and system based on dynamic parameter feedback

Abstract

The invention provides a potassium tert-butoxide production safety regulation and control method and system based on dynamic parameter feedback, and relates to the technical field of potassium tert-butoxide production.The method comprises the following steps that axial temperature field distribution of an evaporation and concentration workshop section and the first concentration gradient of decomposition products are monitored in real time, and according to the axial temperature field distribution, the first concentration gradient of the decomposition products is calculated; obtaining a temperature distribution variable coefficient; if the temperature distribution variable coefficient is larger than a first preset threshold value or the first concentration gradient is larger than a second preset threshold value, inert gas is compensated for the evaporation and concentration workshop section, and / or the tail end evaporation temperature of the evaporation and concentration workshop section is reduced; obtaining a target concentration duration, and judging whether the actual intermediate product concentration reaches the target product concentration or not after the target concentration duration of compensating inert gas and / or reducing the tail end evaporation temperature is executed; if yes, preset drying parameters of the vacuum drying section are kept unchanged, and the intermediate product is subjected to vacuum drying to obtain potassium tert-butoxide. According to the scheme, continuous and safe production can be achieved, and product consistency is high.

Description

Technical Field

[0001] The present application relates to the technical field of potassium tert-butoxide production, and in particular to a method and system for safe regulation of potassium tert-butoxide production based on dynamic parameter feedback. Background Art

[0002] As an important organic base, potassium tert-butoxide is usually produced industrially by reacting metallic potassium with tert-butanol and then preparing it through evaporation concentration, vacuum drying and other processes. The key to the evaporation concentration process is to control the reaction temperature and the accumulation of by-products. Traditional processes often use cyclohexane as a water-carrying agent to achieve continuous removal of water through reactive distillation, but this process has extremely high requirements for the uniformity of the temperature field. Since the axial temperature distribution during the evaporation concentration process is easily affected by local overheating, potassium tert-butoxide may decompose to produce decomposition by-products such as potassium hydroxide or tert-butanol, thereby reducing the purity of the product. In addition, the accumulation of decomposition products will further aggravate the stability problem of the reaction system, forming a vicious circle.

[0003] In the prior art, temperature control mostly relies on experience to set fixed parameters, and lacks a real-time response mechanism to the dynamic changes of the axial temperature field. For example, the invention patent with patent number CN118084615A mentions the removal of moisture through reactive distillation technology, but the real-time monitoring of temperature distribution is insufficient, which may cause the terminal evaporation temperature to be too high, causing local supersaturated crystallization or decomposition reaction. At the same time, fixed parameters are usually used in the vacuum drying stage. If the concentration of the intermediate product does not meet the standard and enters the drying stage, the quality of the final product may be affected by residual solvents or decomposition products. These problems lead to limitations in the existing process such as poor product batch stability and high safety risks. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide a method and system for safe regulation of potassium tert-butoxide production based on dynamic parameter feedback to improve the stability of potassium tert-butoxide production and product consistency.

[0005] In the first aspect, the present application proposes a method for safe production control of potassium tert-butoxide based on dynamic parameter feedback, comprising the following steps: Real-time monitoring of the axial temperature field distribution and the first concentration gradient of the decomposition product in the evaporation and concentration section, and obtaining a temperature distribution variation coefficient according to the axial temperature field distribution; If the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold, inert gas is added to the evaporation and concentration section, and / or the terminal evaporation temperature of the evaporation and concentration section is reduced; Obtaining a target concentration time, and after executing the target concentration time of compensating for inert gas and / or reducing the terminal evaporation temperature, determining whether the actual intermediate product concentration reaches the target product concentration; If so, the preset drying parameters of the vacuum drying section are kept unchanged, and the intermediate product is vacuum dried to obtain potassium tert-butoxide.

[0006] According to the technical solution provided in this application, the method of compensating the evaporation and concentration section with inert gas comprises the following steps: Compensating the evaporation and concentration section with a first compensation amount of inert gas at multiple points, and monitoring the distribution uniformity of the inert gas in real time; If the distribution uniformity is less than a third preset threshold, a non-uniform distribution area is determined, and then a target point corresponding to the non-uniform distribution area is obtained; Based on the distribution uniformity, the first compensation amount is corrected to obtain a second compensation amount; The compensation amount of the inert gas provided by the target point to the evaporation and concentration section is adjusted to the second compensation amount.

[0007] According to the technical solution provided in the present application, the step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: The terminal evaporation temperature of the evaporation concentration section is lowered in a linear cooling mode, and the real-time terminal temperature is compared with a dynamic lower limit value in real time; the dynamic lower limit value is dynamically calculated by the supersaturation curve of the current concentrated liquid; If the absolute value of the difference between the real-time terminal temperature and the dynamic lower limit value is less than a fourth preset threshold, the linear cooling mode is switched to the step cooling mode.

[0008] According to the technical solution provided in the present application, the step cooling mode is a cooling mode in which the temperature drop between every two adjacent cooling steps is lower than a fifth preset threshold and a constant temperature holding period of a first preset time length is set between adjacent cooling steps.

[0009] According to the technical solution provided by the present application, when executing the step cooling mode, the following steps are included: During the constant temperature maintenance period, the intensity of the characteristic peak of the crystal phase transition of the concentrated solution is detected in real time; If the intensity of the characteristic peak of the crystallization phase change exceeds the first safety threshold, the cooling process is terminated.

[0010] According to the technical solution provided by the present application, after terminating the cooling process, the following steps are also included: Ultrasonic stirring is started, and the terminal evaporation temperature is raised at a first temperature recovery rate until the intensity of the characteristic peak of crystallization drops below the first safety threshold.

[0011] According to the technical solution provided in the present application, after the inert gas is compensated to the evaporation and concentration section and before the terminal evaporation temperature of the evaporation and concentration section is lowered, the following steps are included: monitoring the axial pressure difference of each pipe section in real time, and if there is a pipe section with the axial pressure difference greater than a sixth preset threshold, determining the pipe section as a target pipe section; Acquiring circumferential multi-point ultrasonic signal data of the target pipe segment, and judging whether there is microcrystalline potassium tert-butoxide deposition in the target pipe segment according to the multi-point ultrasonic signal data; The step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: If not, lower the terminal evaporation temperature of the evaporation concentration section.

[0012] According to the technical solution provided in the present application, the step of lowering the terminal evaporation temperature of the evaporation concentration section includes the following steps, and further includes the following steps: If so, reducing the current flow rate of the concentrate to a first flow rate, wherein the first flow rate is less than half of the current flow rate; The flow rate of the concentrated liquid is increased in multiple steps, with the increase in the flow rate between two adjacent steps not exceeding 25%, and the temperature of the outer wall of the target pipe section is regulated when the flow rate remains unchanged; If the deposition amount of microcrystalline potassium tert-butoxide in the target pipe section is less than the second safety threshold within the second preset time period, the terminal evaporation temperature of the evaporation concentration section is reduced.

[0013] According to the technical solution provided in the present application, the step of regulating the temperature of the outer wall of the target pipe section comprises the following steps: The heat radiation power distribution of the outer wall of the target pipe segment is adjusted so that the target pipe segment forms alternating supercooling zones and dissolving zones axially, so as to eliminate the microcrystalline potassium tert-butoxide deposited in the target pipe segment; the supercooling zone is a region where the temperature is lower than the dynamic lower limit value, and the dissolving zone is a region where the temperature is higher than the dynamic lower limit value.

[0014] In the second aspect, the present application proposes a potassium tert-butoxide production safety control system based on dynamic parameter feedback, which is used to implement the potassium tert-butoxide production safety control method based on dynamic parameter feedback as described above; comprising: A monitoring module, wherein the monitoring module is configured to monitor the axial temperature field distribution and the first concentration gradient of the decomposition product of the evaporation and concentration section in real time, and obtain a temperature distribution variation coefficient according to the axial temperature field distribution; A control module, wherein the control module is configured to compensate the evaporation and concentration section with inert gas and / or reduce the terminal evaporation temperature of the evaporation and concentration section if the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold; A judgment module, the judgment module is configured to obtain a target concentration time, and after executing the target concentration time of compensating for the inert gas and / or reducing the terminal evaporation temperature, judge whether the actual intermediate product concentration reaches the target product concentration; The judgment module is also configured to maintain the preset drying parameters of the vacuum drying section unchanged when the actual intermediate product concentration reaches the target product concentration, and vacuum dry the intermediate product to obtain potassium tert-butoxide.

[0015] Compared with the prior art, the beneficial effects of the present application are as follows: the present application monitors the axial temperature field distribution and the concentration gradient of the decomposition products in the evaporation and concentration section in real time, calculates the coefficient of variation of the temperature distribution, and dynamically determines the risk of local overheating. When the coefficient of variation or the concentration gradient exceeds the standard, the inert gas compensation can inhibit the chain propagation of the decomposition reaction (and also reduce the risk of explosion by reducing the oxygen content, improving safety), while reducing the terminal evaporation temperature to avoid supersaturated crystallization, thereby controlling the concentration of by-products within the safety threshold. Compared with traditional fixed parameter control, this technology uses the coefficient of variation of the temperature field as a quantitative indicator, which significantly improves the control accuracy. In addition, after the inert gas compensation and temperature reduction control, the concentration of the intermediate product is verified to ensure that the material entering the vacuum drying stage meets the purity requirements. This mechanism avoids the problem of premature or late drying in the traditional process. Combined with the maintenance of the parameters of the vacuum drying section, the product consistency can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flow chart of the steps of the potassium tert-butoxide production safety control system based on dynamic parameter feedback provided in this application. DETAILED DESCRIPTION

[0017] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0018] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] Example 1 The production process of potassium tert-butoxide is as follows: first, a chemical reaction between metallic potassium and tert-butanol is carried out in a reactor to generate a reaction liquid, and the reaction liquid is transported to an evaporation and concentration section and heated by a heating device to gradually evaporate low-boiling-point substances such as tert-butanol, thereby increasing the concentration of potassium tert-butoxide and forming a concentrated solution. The concentrated solution after evaporation and concentration is then subjected to subsequent separation, purification and other process steps to further remove impurities and improve the purity of potassium tert-butoxide. Finally, after drying treatment in a vacuum drying section, a high-purity finished product of potassium tert-butoxide is obtained, which can be used in downstream industries such as organic synthesis and drug preparation. As mentioned in the background technology, in response to the problems in the prior art, the present application proposes a method for safe regulation and control of potassium tert-butoxide production based on dynamic parameter feedback, such as Figure 1 As shown, the following steps are included: S1. Real-time monitoring of the axial temperature field distribution and the first concentration gradient of the decomposition product in the evaporation and concentration section, and obtaining a temperature distribution variation coefficient according to the axial temperature field distribution; Specifically, the axial temperature field distribution in this step refers to the temperature distribution in the axial direction of the equipment (such as pipelines, etc.) in the evaporation and concentration section; the first concentration gradient refers to the concentration change rate of the decomposition product in the space of the evaporation and concentration section. The coefficient of variation of the temperature distribution is a statistic that measures the degree of dispersion of the axial temperature field distribution. It is obtained by calculating the ratio of the standard deviation of the temperature data to the average value, and is used to quantify the degree of unevenness of the temperature distribution.

[0020] Specifically, the axial temperature data collected by the temperature sensor is sorted and statistically analyzed, the average value and standard deviation of the temperature data are calculated, and then the quotient of the standard deviation and the average value is used as the coefficient of variation of the temperature distribution. For example, the axial temperature data collected at a certain moment is [50, 52, 48, 55, 49]. The average value is 50.8 and the standard deviation is 2.77. The coefficient of variation of the temperature distribution is about 0.055.

[0021] S2. If the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold, inert gas is added to the evaporation and concentration section, and / or the terminal evaporation temperature of the evaporation and concentration section is lowered; Exemplarily, the first preset threshold is 0.15, and the second preset threshold is 1.2 times the hourly change rate of the decomposition product concentration during normal production.

[0022] Specifically, the coefficient of variation of the temperature distribution reflects the degree of discreteness of the axial temperature field distribution in the evaporation and concentration section. If it is greater than the first preset threshold, it means that the axial temperature field is unevenly distributed, and there may be local overheating or overcooling areas. Local overheating may lead to an intensification of the decomposition reaction, an increase in the number of decomposition products, and may also trigger side reactions, affecting the purity and quality of potassium tert-butoxide; local overcooling may cause inconsistent reaction rates, reduce production efficiency, and even cause abnormal crystallization of the concentrated liquid and block the pipeline. When the first concentration gradient is greater than the second preset threshold, it indicates that the concentration of the decomposition product changes too drastically. This suggests that the decomposition reaction proceeds rapidly in a short period of time, which may be due to out-of-control reaction conditions, such as abnormal temperature and pressure, or the presence of certain unstable factors in the reaction system, which will not only increase the content of the decomposition product, but also may cause corrosion or damage to the production equipment, seriously threatening production safety. Therefore, once the above situation occurs, it is necessary to take timely measures to compensate the inert gas to the evaporation and concentration section and / or reduce the terminal evaporation temperature to stabilize the production process and ensure product quality and production safety.

[0023] Furthermore, the said compensating the said evaporation and concentration section with inert gas comprises the following steps: Compensating the evaporation and concentration section with a first compensation amount of inert gas at multiple points, and monitoring the distribution uniformity of the inert gas in real time; If the distribution uniformity is less than a third preset threshold, a non-uniform distribution area is determined, and then a target point corresponding to the non-uniform distribution area is obtained; Based on the distribution uniformity, the first compensation amount is corrected to obtain a second compensation amount; The compensation amount of the inert gas provided by the target point to the evaporation and concentration section is adjusted to the second compensation amount.

[0024] Specifically, gas injection ports are set at multiple locations such as the top, middle and bottom of the evaporation and concentration section, and an inert gas (such as nitrogen) is compensated therein with a first compensation amount (such as 5 liters per cubic meter, for example, set according to the equipment volume and safety requirements). By arranging multiple gas concentration sensors in the section, the distribution uniformity of the inert gas is monitored in real time. If the distribution uniformity is less than the third preset threshold (such as 0.8), the non-uniform distribution area is determined by analyzing the data of each sensor, and then the corresponding target point is located. Based on the distribution uniformity, the proportional correction method is used to correct the first compensation amount. For example, when the distribution uniformity is 0.6, the second compensation amount is adjusted to 1.5 times the first compensation amount (for example), and the compensation amount of the target point is adjusted to the second compensation amount.

[0025] This embodiment provides an optimization method for inert gas compensation during abnormality, and multi-point compensation of inert gas can quickly dilute decomposition products, reduce their concentration, and reduce the possibility of dangerous decomposition product concentration being too high. At the same time, monitor the uniformity of distribution and correct the compensation amount to ensure that the inert gas is evenly distributed in the evaporation and concentration section, avoid the safety hazards in local areas due to lack of inert gas protection, and ensure production safety in an all-round way. At the same time, a stable reaction environment is the key to ensuring product quality. When temperature distribution or concentration abnormality occurs, timely compensate inert gas and optimize its distribution, stabilize reaction conditions, prevent side reactions from occurring due to local overheating, supercooling or excessive concentration of decomposition products, and then avoid the increase of impurities in the product, ensure the purity and quality stability of potassium tert-butoxide, and improve the consistency between product batches. Therefore, the inert gas compensation strategy can make the reaction return to normal state quickly, reduce production interruptions or adjustment time caused by abnormal conditions. Avoid repeatedly adjusting process parameters due to production abnormalities, so that the evaporation and concentration section can be operated more efficiently, shorten the production cycle, and improve the production efficiency of potassium tert-butoxide.

[0026] Furthermore, the step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: The terminal evaporation temperature of the evaporation concentration section is lowered in a linear cooling mode, and the real-time terminal temperature is compared with a dynamic lower limit value in real time; the dynamic lower limit value is dynamically calculated by the supersaturation curve of the current concentrated liquid; Specifically, the terminal evaporation temperature refers to the temperature of the position about to leave the evaporation and concentration section. The temperature here directly determines the state of the final concentrated liquid. Lowering the temperature at this position can directly affect the evaporation degree of the concentrated liquid and the final concentration of the product, effectively control the concentration process, avoid excessive evaporation or insufficient concentration, ensure that the product quality meets the requirements, and also meet the continuity of the production process. First, it is necessary to experimentally determine the supersaturation data of the concentrated liquid at different temperatures and concentrations. During the experiment, the temperature is precisely controlled, the concentration of the concentrated liquid is gradually changed, and the temperature-concentration correspondence when the concentrated liquid begins to be supersaturated is recorded. Based on these experimental data, mathematical fitting methods, such as the least squares method, are used to construct a mathematical model of the supersaturation curve of the current concentrated liquid. In actual production, the current concentration of the concentrated liquid is obtained in real time, and it is substituted into the mathematical model of the supersaturation curve to calculate the corresponding dynamic lower limit. Use a temperature controller to set a linear cooling mode, such as reducing 1°C per minute.

[0027] If the absolute value of the difference between the real-time terminal temperature and the dynamic lower limit value is less than a fourth preset threshold, the linear cooling mode is switched to the step cooling mode.

[0028] Specifically, if the absolute value of the difference between the real-time terminal temperature and the dynamic lower limit value is smaller than a fourth preset threshold value (such as 0.5° C.), the controller switches to the step cooling mode.

[0029] Furthermore, the step cooling mode is a cooling mode in which the temperature drop amplitude between every two adjacent cooling steps is lower than a fifth preset threshold value and a constant temperature holding period of a first preset time length is set between adjacent cooling steps.

[0030] Specifically, the temperature drop between every two adjacent cooling steps is set to be lower than a fifth preset threshold (such as 0.3°C), and a constant temperature holding period of a first preset time (such as 10 minutes) is set between adjacent cooling steps. The temperature controller performs step-by-step cooling according to the set program.

[0031] The cooling mode proposed in this embodiment can improve production safety. By comparing the real-time terminal temperature with the dynamic lower limit value dynamically calculated by the supersaturation curve of the concentrated solution in real time, the temperature can be effectively avoided to be too low. When the temperature is lower than the dynamic lower limit value, the concentrated solution may be over-crystallized, resulting in pipeline blockage, affecting the continuity of production and even causing safety accidents. Through this precise temperature control, the cooling strategy can be adjusted in time to prevent the occurrence of such dangerous situations. The step cooling mode avoids the rapid change of temperature, prevents the violent boiling or decomposition reaction of the concentrated solution caused by the sudden change of temperature, thereby ensuring the safety and stability of the production process. The combination of linear cooling and step cooling can make the concentrated solution slowly crystallize under suitable temperature conditions. During the constant temperature maintenance period of step cooling, the concentrated solution has enough time to crystallize in an orderly manner, avoiding insufficient crystallization or irregular crystal morphology caused by too fast temperature change, thereby improving the crystal quality of potassium tert-butoxide and ensuring the purity and consistency of the product. A reasonable cooling strategy helps to maintain a stable reaction environment and reduce side reactions caused by abnormal temperature. During the evaporation and concentration process, excessively high or large temperature fluctuations may cause potassium tert-butoxide to decompose or react with other impurities, affecting product quality. By strictly controlling the cooling process, the probability of side reactions can be effectively reduced, and the quality and yield of the product can be improved. Through precise temperature control and reasonable switching of cooling modes, the evaporation and concentration section can reach the target concentration state in the shortest time. It avoids the extension of the production cycle caused by improper temperature control, improves the utilization rate of equipment, and thus improves the overall production efficiency.

[0032] S3, obtaining a target concentration time, and after executing the target concentration time of compensating for the inert gas and / or lowering the terminal evaporation temperature, determining whether the actual intermediate product concentration reaches the target product concentration; Specifically, the target concentration time refers to the difference between the preset concentration time and the historical concentration period before the start of inert gas compensation and / or lowering of the terminal evaporation temperature, that is, the normal remaining concentration time. The preset concentration time is determined before production based on product demand. For the continuity of production, the reaction time, evaporation time, drying time, etc. are all determined in advance. The preset concentration time can be calculated based on past experience, production process standards or theoretical models, and is an estimated time from the input of raw materials to the intermediate product reaching the target concentration.

[0033] S4. If yes, keep the preset drying parameters of the vacuum drying section unchanged and vacuum dry the intermediate product to obtain potassium tert-butoxide.

[0034] Specifically, the operator can clearly grasp the production progress. By clarifying the normal remaining concentration time, the production can be carried out in an orderly manner according to the established plan, avoiding blind waiting or over-concentration. For example, after monitoring the abnormal parameters that need to be regulated, the operation can be quickly adjusted according to the target concentration time, and the subsequent processes can be reasonably arranged, which greatly improves the controllability and planning of the production process. After the target concentration time, it is judged whether the actual intermediate product concentration meets the standard to ensure the stability of the intermediate product quality entering the vacuum drying stage. Only when the intermediate product reaches the appropriate concentration, the subsequent drying process is carried out to avoid product quality fluctuations due to concentration deviations. If the concentration is too high or too low, it may affect the purity and crystal form of the final potassium tert-butoxide, and the judgment link of S3 effectively avoids such problems. Then, the concentration of the intermediate product before entering the vacuum drying section meets the standard, and the preset drying parameters of the vacuum drying section are kept unchanged in S4, which ensures that the conditions of each batch of potassium tert-butoxide are the same during the drying process, and jointly achieve the effect of improving product quality consistency, avoiding differences in indicators such as product water content and crystallinity due to fluctuations in drying parameters.

[0035] In a preferred embodiment, when executing the step cooling mode, the following steps are included: During the constant temperature maintenance period, the intensity of the characteristic peak of the crystal phase transition of the concentrated solution is detected in real time; If the intensity of the characteristic peak of the crystallization phase change exceeds the first safety threshold, the cooling process is terminated.

[0036] Furthermore, after the cooling process is terminated, the following steps are also included: Ultrasonic stirring is started, and the terminal evaporation temperature is raised at a first temperature recovery rate until the intensity of the characteristic peak of crystallization drops below the first safety threshold.

[0037] Specifically, during the crystallization process of the concentrated solution, the crystal structure of the substance changes. Different crystal structures will produce characteristic diffraction peaks under specific detection methods (such as X-ray diffraction analysis). The intensity of these diffraction peaks is the intensity of the characteristic peaks of the crystallization phase transition. It reflects the growth of crystals and the degree of crystallization in the concentrated solution. The acquisition method is: during the constant temperature holding period, aim the probe of the X-ray diffractometer at the concentrated solution sample, set the appropriate scanning range and time, and the corresponding characteristic peak intensity value can be obtained. The first safety threshold is a pre-set critical value for judging whether the intensity of the characteristic peak of the crystallization phase transition is within the safety range. It is determined based on a large amount of experimental data and production experience. When the intensity of the characteristic peak of the crystallization phase transition exceeds this threshold, it may have an adverse effect on the product quality or the production process. The acquisition method is: through a large number of experiments in the early stage, record the product quality and production conditions under different crystallization phase transition characteristic peak intensities, and comprehensively analyze and determine a suitable value as the first safety threshold. For example, after many experiments, it was found that when the intensity of the characteristic peak of the crystallization phase transition exceeded 80 (the unit was determined according to the actual detection method), the purity and crystal morphology of the product showed obvious abnormalities, so 80 can be used as the first safety threshold. The first temperature recovery rate refers to the speed at which the terminal evaporation temperature recovers after the cooling process is terminated. It determines how fast the temperature recovers and has an important impact on the adjustment of the crystallization state of the concentrate. The method of obtaining it is determined according to the characteristics of the concentrate, the heating capacity of the equipment, and the production process requirements. For example, for a specific concentrate, after testing and process evaluation, it is determined that the terminal evaporation temperature can be raised by 0.2°C per minute while ensuring product quality and efficiently adjusting the crystallization state. Then 0.2°C / minute is the first temperature recovery rate.

[0038] The step cooling mode proposed in this embodiment avoids the crystal structure defects and impurities caused by excessive crystallization, and ensures the quality and purity of potassium tert-butoxide crystals. After terminating cooling, further optimize the crystal structure, improve the stability and consistency of product quality, and solve the problem of product quality fluctuation caused by improper temperature control in the prior art. In the crystallization process, excessive crystallization may cause the potential safety hazards such as pressure change inside the equipment and pipeline blockage. By monitoring the intensity of the characteristic peak of the crystallization phase transition, timely stop cooling and take temperature recovery measures, effectively avoid these potential safety problems, improve the safety of the production process, and make up for the defects of the insufficient control means of the prior art in the face of abnormal crystallization. Timely termination of cooling, ultrasonic stirring and temperature recovery operation allows the crystallization process to be carried out in the best state, reduces the production interruption caused by crystallization problems and the situation that the product is unqualified and needs to be reprocessed, improves production efficiency, improves product yield, and realizes the efficient operation of the production process.

[0039] In a preferred embodiment, after the inert gas is supplemented to the evaporation and concentration section and before the terminal evaporation temperature of the evaporation and concentration section is lowered, the following steps are included: monitoring the axial pressure difference of each pipe section in real time, and if there is a pipe section with the axial pressure difference greater than a sixth preset threshold, determining the pipe section as a target pipe section; Specifically, in the evaporation and concentration section of potassium tert-butoxide production, there are various pipelines for conveying concentrated liquids, steam and other fluids. These pipelines are divided into different parts according to function, location or process requirements, and each part is a pipe section. For example, the feed pipeline connected from the reactor to the evaporator can be regarded as a pipe section, and the pipelines at different levels or different directions inside the evaporator also constitute independent pipe sections. The discharge pipeline from the evaporator to the subsequent separation equipment is also one of the pipe sections. The axial pressure difference refers to the pressure difference between two different positions on the axial direction of the same pipe section. The sixth preset threshold is obtained by collecting the axial pressure difference data of each pipe section in past production, calculating its average value and standard deviation, and adding a certain multiple of the standard deviation (such as 2 times the standard deviation) to the average value, such as 0.05MPa. If the axial pressure difference of a pipe section is greater than the sixth preset threshold, it is a target pipe section that may have a deposition problem, and it is necessary to further determine whether there is a deposition situation.

[0040] Acquiring circumferential multi-point ultrasonic signal data of the target pipe segment, and judging whether there is microcrystalline potassium tert-butoxide deposition in the target pipe segment according to the multi-point ultrasonic signal data; Optionally, an ultrasonic signal method is selected to further determine whether there is deposition. Specifically, by analyzing the intensity, phase, propagation time and other parameters of the reflected ultrasonic signal, it is possible to determine whether there is deposition and the location and approximate thickness of the deposition. Therefore, this step also includes obtaining the location and thickness of the deposition based on the multi-point ultrasonic signal data; The step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: If not, lower the terminal evaporation temperature of the evaporation concentration section.

[0041] Specifically, if there is microcrystalline potassium tert-butoxide deposition, as the temperature decreases, the deposition may intensify, leading to pipeline blockage, abnormal local pressure, increased risk of equipment damage, and shortened equipment service life. However, judging that there is no deposition first and then cooling down can avoid equipment problems caused by deposition, ensure stable operation of equipment, reduce maintenance costs and downtime, and ensure production continuity; cooling down when there is deposition will interfere with the flow and heat transfer uniformity of the concentrate, causing local concentration and temperature abnormalities, affecting the crystallization process of potassium tert-butoxide, resulting in decreased product purity and irregular crystal morphology. Judging that there is no deposition first and then cooling down can provide a stable environment for crystallization, ensuring stable product quality, high purity, and good crystal morphology. For example, a stable crystallization environment is crucial for the production of high-purity potassium tert-butoxide for drug synthesis.

[0042] Furthermore, the step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps, and further comprises the following steps: If so, reducing the current flow rate of the concentrate to a first flow rate, wherein the first flow rate is less than half of the current flow rate; Specifically, the first flow rate refers to a specific flow rate to which the current flow rate of the concentrate needs to be reduced when microcrystalline potassium tert-butoxide is detected in the target pipe segment. It is to change the flow state of the concentrate in the pipe segment to reduce the further deposition of microcrystalline potassium tert-butoxide and create conditions for the subsequent treatment of the deposition problem. The acquisition method is: according to the pipe diameter, internal structure and properties of the concentrated liquid of the target pipe segment, it is determined by fluid mechanics calculation or experimental test. For example, for a target pipe segment with a pipe diameter of 50mm, when the current flow rate is 10L / min, it is more appropriate to reduce the flow rate to 4L / min (less than 5L / min, i.e. half of the current flow rate) through calculation or experiment, then 4L / min is the first flow rate. Usually, 30%-40% of the current flow rate is used as the first flow rate.

[0043] The flow rate of the concentrated liquid is increased in multiple steps, with the increase in the flow rate between two adjacent steps not exceeding 25%, and the temperature of the outer wall of the target pipe section is regulated when the flow rate remains unchanged; If the deposition amount of microcrystalline potassium tert-butoxide in the target pipe section is less than the second safety threshold within the second preset time period, the terminal evaporation temperature of the evaporation concentration section is reduced.

[0044] Specifically, the second preset duration is a time limit set when dealing with the problem of microcrystalline potassium tert-butoxide deposition in the target pipe section. During this time, by adjusting the flow rate and the temperature of the outer wall of the pipe section and other measures, the change in the deposition amount of microcrystalline potassium tert-butoxide is observed. The acquisition method is: based on production experience and research on the dissolution or removal rate of deposited materials in the pipe section. For example, after many experiments and actual production verification, it is found that it usually takes about 30 minutes to observe obvious effects when dealing with the problem of microcrystalline potassium tert-butoxide deposition, so the second preset duration is set to 30 minutes. The second safety threshold is a critical value for judging whether the amount of microcrystalline potassium tert-butoxide deposition in the target pipe section is within a safe range. When the deposition amount is less than the threshold, it is believed that the deposition in the pipe section will not have a serious impact on subsequent production, and the operation of reducing the terminal evaporation temperature can continue. The acquisition method is: by simulating the operation of the pipe section under different deposition amounts and the impact on product quality, combined with production safety standards. For example, simulations and experiments have shown that when the amount of microcrystalline potassium tert-butoxide deposited in the target pipe section is less than 0.5 kg per cubic meter, it will not affect the normal flow of the fluid in the pipe section and the product quality. Therefore, 0.5 kg / m³ is the second safety threshold.

[0045] This embodiment takes into account the problem of microcrystalline potassium tert-butoxide deposition that often occurs in production scenarios on the basis of the original embodiment. By real-time monitoring of the axial pressure difference of each pipe section, potential pipeline blockage or abnormal conditions can be discovered in time to avoid production interruptions or even safety accidents caused by pipe section problems. When microcrystalline potassium tert-butoxide deposition is found, measures such as reducing the flow rate, increasing the flow rate in a step-by-step manner, and regulating the temperature of the outer wall of the pipe section are taken to effectively reduce the impact of deposition on production, ensure the safe and stable operation of the production process, and further solve the safety hazards caused by pipeline problems in the prior art. By monitoring and processing the deposition of microcrystalline potassium tert-butoxide in the target pipe section, the normal flow and uniform distribution of the concentrate in the pipe section are ensured, and the uneven concentration of the concentrate caused by deposition is avoided, thereby ensuring the quality stability of the potassium tert-butoxide product, improving the consistency of the product, and making up for the shortcomings of the prior art in product quality control.

[0046] Further, regulating the temperature of the outer wall of the target pipe section comprises the following steps: The heat radiation power distribution of the outer wall of the target pipe segment is adjusted so that the target pipe segment forms alternating supercooling zones and dissolving zones axially, so as to eliminate the microcrystalline potassium tert-butoxide deposited in the target pipe segment; the supercooling zone is a region where the temperature is lower than the dynamic lower limit value, and the dissolving zone is a region where the temperature is higher than the dynamic lower limit value.

[0047] Specifically, the thermal radiation power distribution refers to the distribution of the power of heat radiated outward per unit area on the outer wall of the target pipe segment in the axial direction. For the target pipe segment, the thermal radiation power distribution can be changed by adjusting the power of the outer wall heating element (such as an electric heating wire). A plurality of heat flux sensors are installed on the outer wall of the pipe segment, which can measure the heat passing through the unit area per unit time, thereby obtaining the thermal radiation power data at different positions, and then determining the thermal radiation power distribution. For example, a heat flux sensor is installed at a certain distance (such as 0.5 meters), and data is collected in real time to draw a distribution curve of the thermal radiation power along the axial direction of the pipe segment. The outer wall of the target pipe segment is divided into multiple areas along the axial direction, and each area corresponds to an independent heating element, such as an electric heating wire or a heating plate. By adjusting the power supply of the heating elements in different areas, the differential control of the thermal radiation power is achieved. For example, for the area where the supercooling zone needs to be formed, the power of the heating element is reduced or even turned off; for the dissolving zone, the power of the heating element is increased to form an alternating temperature zone.

[0048] Before adjusting the heat radiation power distribution of the outer wall of the target pipe section so that the target pipe section forms alternating supercooling zones and dissolving zones in the axial direction, it also includes determining a parameter set, where the parameter set is a setting rule for the supercooling zones and the dissolving zones; determining the parameter set includes the following steps: According to the above-mentioned deposition position and thickness obtained through the ultrasonic signal data, the corresponding setting position and setting area size are obtained; According to the setting area size, the setting ratio and alternating number of the supercooling zone and the dissolving zone are obtained; The heat radiation power distribution of the outer wall of the target pipe segment is adjusted so that supercooling zones and dissolving zones with set proportions and alternating numbers are formed at the set positions corresponding to the target pipe segment.

[0049] Specifically, adjust the number of alternations and the size of the area according to the severity of the deposition. For example, in areas with severe deposition, shorten the number of alternations so that the supercooling zone and the dissolving zone alternate closely to enhance the deposition elimination effect; in areas with lighter deposition, appropriately increase the number of alternations and the size of the area; refer to past production experience in dealing with similar deposition problems, as well as experimental data for the conditions of the concentrate and pipe section. Through multiple experiments, record the deposition elimination effects under different arrangements of supercooling zones and dissolving zones, establish a database, and provide a reference for actual production. For example, it was found through experiments that under certain concentrated liquid and pipe section conditions, the deposition elimination effect is best when the length ratio of the supercooling zone and the dissolving zone is 1:2 and the number of alternations is 3. This parameter setting can be used as a reference in actual production.

[0050] The deposition elimination method of alternately forming supercooling zones and dissolving zones proposed in this embodiment continuously changes the dissolution and crystallization state of microcrystalline potassium tert-butoxide. The change of the crystal structure in the supercooling zone makes it easier to be dissolved when entering the dissolving zone, and the repeated alternation strengthens the deposition elimination effect. Compared with the single temperature zone setting, the alternating zone can more comprehensively and efficiently handle deposition at different positions and to different degrees in the pipe section, improve the efficiency and thoroughness of deposition elimination, thereby promptly solving the deposition problem and effectively ensuring production continuity and safety.

[0051] Example 2 On the basis of Example 1, this embodiment proposes a potassium tert-butoxide production safety control system based on dynamic parameter feedback, which is used to implement the potassium tert-butoxide production safety control method based on dynamic parameter feedback as described in Example 1; comprising: A monitoring module, wherein the monitoring module is configured to monitor the axial temperature field distribution and the first concentration gradient of the decomposition product of the evaporation and concentration section in real time, and obtain a temperature distribution variation coefficient according to the axial temperature field distribution; A control module, wherein the control module is configured to compensate the evaporation and concentration section with inert gas and / or reduce the terminal evaporation temperature of the evaporation and concentration section if the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold; A judgment module, the judgment module is configured to obtain a target concentration time, and after executing the target concentration time of compensating for the inert gas and / or reducing the terminal evaporation temperature, judge whether the actual intermediate product concentration reaches the target product concentration; The judgment module is also configured to maintain the preset drying parameters of the vacuum drying section unchanged when the actual intermediate product concentration reaches the target product concentration, and vacuum dry the intermediate product to obtain potassium tert-butoxide.

[0052] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A method for safe production and regulation of potassium tert-butoxide based on dynamic parameter feedback, characterized in that: The following steps are involved: Real-time monitoring of the axial temperature field distribution and the first concentration gradient of the decomposition product in the evaporation and concentration section, and obtaining a temperature distribution variation coefficient according to the axial temperature field distribution; If the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold, inert gas is compensated to the evaporation concentration section, and / or the terminal evaporation temperature of the evaporation concentration section is reduced; Obtaining a target concentration time, and after executing the target concentration time of compensating for inert gas and / or lowering the terminal evaporation temperature, determining whether the actual intermediate product concentration reaches the target product concentration; If so, the preset drying parameters of the vacuum drying section are kept unchanged, and the intermediate product is vacuum dried to obtain potassium tert-butoxide.

2. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 1, characterized in that: The method of compensating the evaporation and concentration section with inert gas comprises the following steps: Compensating the evaporation and concentration section with a first compensation amount of inert gas at multiple points, and monitoring the distribution uniformity of the inert gas in real time; If the distribution uniformity is less than a third preset threshold, a non-uniform distribution area is determined, and then a target point corresponding to the non-uniform distribution area is obtained; Based on the distribution uniformity, the first compensation amount is corrected to obtain a second compensation amount; The compensation amount of the inert gas provided by the target point to the evaporation and concentration section is adjusted to the second compensation amount.

3. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 1, characterized in that: The step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: The terminal evaporation temperature of the evaporation concentration section is lowered in a linear cooling mode, and the real-time terminal temperature is compared with a dynamic lower limit value in real time; the dynamic lower limit value is dynamically calculated by the supersaturation curve of the current concentrated liquid; If the absolute value of the difference between the real-time terminal temperature and the dynamic lower limit value is less than a fourth preset threshold, the linear cooling mode is switched to the step cooling mode.

4. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 3, characterized in that: The step cooling mode is a cooling mode in which the temperature drop amplitude between every two adjacent cooling steps is lower than a fifth preset threshold value and a constant temperature holding period of a first preset time length is set between adjacent cooling steps.

5. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 4, characterized in that: When executing the step cooling mode, the following steps are included: During the constant temperature maintenance period, the intensity of the characteristic peak of the crystal phase transition of the concentrated solution is detected in real time; If the intensity of the characteristic peak of the crystallization phase change exceeds the first safety threshold, the cooling process is terminated.

6. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 5, characterized in that: After the cooling process is terminated, the following steps are also included: Ultrasonic stirring is started, and the terminal evaporation temperature is raised at a first temperature recovery rate until the intensity of the characteristic peak of crystallization drops below the first safety threshold.

7. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 1, characterized in that: After the inert gas is added to the evaporation and concentration section and before the terminal evaporation temperature of the evaporation and concentration section is lowered, the following steps are included: monitoring the axial pressure difference of each pipe section in real time, and if there is a pipe section with the axial pressure difference greater than a sixth preset threshold, determining the pipe section as a target pipe section; Acquiring circumferential multi-point ultrasonic signal data of the target pipe segment, and judging whether there is microcrystalline potassium tert-butoxide deposition in the target pipe segment according to the multi-point ultrasonic signal data; The step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps: If not, lower the terminal evaporation temperature of the evaporation concentration section.

8. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 7, characterized in that: The step of lowering the terminal evaporation temperature of the evaporation concentration section comprises the following steps, and further comprises the following steps: If so, reducing the current flow rate of the concentrate to a first flow rate, wherein the first flow rate is less than half of the current flow rate; The flow rate of the concentrated liquid is increased in multiple steps, with the increase in the flow rate between two adjacent steps not exceeding 25%, and the temperature of the outer wall of the target pipe section is regulated when the flow rate remains unchanged; If the deposition amount of microcrystalline potassium tert-butoxide in the target pipe section is less than the second safety threshold within the second preset time period, the terminal evaporation temperature of the evaporation concentration section is reduced.

9. The method for controlling the production safety of potassium tert-butoxide based on dynamic parameter feedback according to claim 8, characterized in that: The step of regulating the temperature of the outer wall of the target pipe section comprises the following steps: The heat radiation power distribution of the outer wall of the target pipe segment is adjusted so that the target pipe segment forms alternating supercooling zones and dissolving zones axially, so as to eliminate the microcrystalline potassium tert-butoxide deposited in the target pipe segment; the supercooling zone is a region where the temperature is lower than the dynamic lower limit value, and the dissolving zone is a region where the temperature is higher than the dynamic lower limit value.

10. A potassium tert-butoxide production safety control system based on dynamic parameter feedback, used to implement the potassium tert-butoxide production safety control method based on dynamic parameter feedback as described in any one of claims 1 to 9; characterized in that, include: A monitoring module, wherein the monitoring module is configured to monitor the axial temperature field distribution and the first concentration gradient of the decomposition product of the evaporation and concentration section in real time, and obtain a temperature distribution variation coefficient according to the axial temperature field distribution; A control module, wherein the control module is configured to compensate the evaporation and concentration section with inert gas and / or reduce the terminal evaporation temperature of the evaporation and concentration section if the temperature distribution variation coefficient is greater than a first preset threshold or the first concentration gradient is greater than a second preset threshold; A judgment module, the judgment module is configured to obtain a target concentration time, and after executing the target concentration time of compensating for the inert gas and / or reducing the terminal evaporation temperature, judge whether the actual intermediate product concentration reaches the target product concentration; The judgment module is also configured to maintain the preset drying parameters of the vacuum drying section unchanged when the actual intermediate product concentration reaches the target product concentration, and vacuum dry the intermediate product to obtain potassium tert-butoxide.

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