Method and system for measuring and analyzing material mixing and dispersing heat effect

Abstract

The invention discloses a method for measuring and analyzing a material mixing and dispersing heat effect. The method comprises the following steps: adding a backing material and a charging material into a reactor, and mixing; measuring heat flow data of the wall surface of the reactor in the mixing process and calculating first mixing dispersion heat; fitting the calculated first mixed dispersion heat, the mole fraction of the base material in the mixed material and the mole fraction of the added material in the mixed material by adopting a plurality of thermodynamic models, selecting the normalized mean square deviation root deviation of a fitting result, and determining the thermodynamic model of which the coefficient and the absolute average error both meet threshold requirements; calculating a second mixing dispersion heat based on the selected thermodynamic model; and correcting the heat in the reaction process after the materials are mixed by adopting the second mixing dispersion heat. The invention further discloses a measurement and analysis system for implementing the method. The thermal effect in the reaction process is corrected, and the real reliability of monitoring parameters in the chemical reaction process is effectively improved.

Description

Technical Field

[0001] The invention relates to a thermal effect measurement and analysis method and system, belonging to the technical field of heat measurement. Background Art

[0002] Solvent-free chemical reaction is a chemical reaction in which the reaction materials are directly mixed in the absence of traditional liquid solvents. It can achieve faster reaction rates and higher selectivity, while avoiding the use and treatment of solvents, reducing environmental pollution in the chemical manufacturing process, and improving the atomic economy of the reaction process.

[0003] When there is no solvent in the reaction system, the thermal effect of the reaction materials during the mixing and dispersion process becomes particularly prominent. The heat absorbed or released during the mixing and dispersion of the reaction materials will directly affect the reaction progress. Since the thermal effect brought about by the mixing and dispersion occurs synchronously with the energy change of the reaction process, this part of energy is difficult to obtain through direct measurement, resulting in the neglect of the thermal effect of material mixing and dispersion, which in turn leads to misjudgment and misoperation of the reaction progress. Summary of the invention

[0004] In view of the above-mentioned defects in the prior art, the task of the present invention is to provide a method for measuring and analyzing the thermal effects of material mixing and dispersion. Another task of the present invention is to provide a system for measuring and analyzing the thermal effects of material mixing and dispersion, so as to measure the thermal effects brought about by the mixing and dispersion of initial materials and subsequent feeds during a chemical reaction.

[0005] The technical solution of the present invention is as follows: A method for measuring and analyzing the thermal effect of material mixing and dispersion, comprising the steps of: Adding the base material and the feed material into the reactor for mixing; During the mixing process, the heat flow data of the reactor wall is measured and the first mixing dispersion heat is calculated; Using several thermodynamic models to fit the calculated first mixed dispersion heat, the mole fraction of the base material in the mixed material, and the mole fraction of the added material in the mixed material, and selecting a thermodynamic model whose normalized root mean square deviation, coefficient of determination, and absolute mean error of the fitting results all meet the threshold requirements; calculating a second mixed dispersion heat based on a selected thermodynamic model; The second mixing and dispersing heat is used to correct the heat of the reaction process after the materials are mixed.

[0006] Furthermore, the thermodynamic model includes the Van Laar equation, the Margules equation and the Wilson equation.

[0007] Furthermore, the threshold requirement of the normalized root mean square deviation is <5%, the threshold requirement of the determination coefficient is >0.99, and the threshold requirement of the absolute mean error is <5%.

[0008] Furthermore, the following formula is used to calculate the first mixed dispersion heat: , in, Disperse heat for the first mix, is the real-time heat flux on the reactor wall, S is the heat exchange inner wall area of ​​the reactor, t is the mixing dispersion heat flow measurement time, t 0 is the starting time of heat flow measurement, t 1 is the end time of heat flow measurement.

[0009] Furthermore, the use of the second mixed dispersion heat to correct the heat of the reaction process is based on the following formula: , in, is the measured value of heat during the reaction after material mixing. Dissipate heat for the second mix.

[0010] Another technical solution of the present invention is as follows: A measurement and analysis system for material mixing and dispersion thermal effects, comprising a feeding module, a first calculation module, a fitting module, a second calculation module and a correction module; The feeding module is used to add the base material and the feed material into the reactor for mixing; The first calculation module is used to measure the heat flow data of the reactor wall during the mixing process and calculate the first mixing dispersion heat; The fitting module uses several thermodynamic models to fit the calculated first mixed dispersion heat, the molar fraction of the base material in the mixed material, and the molar fraction of the added material in the mixed material, and selects a thermodynamic model whose normalized root mean square deviation, coefficient of determination, and absolute mean error of the fitting results all meet the threshold requirements; The second calculation module is used to calculate the second mixed dispersion heat based on the selected thermodynamic model; The correction module uses the second mixed dispersion heat to correct the heat of the reaction process after the materials are mixed.

[0011] Furthermore, the thermodynamic model includes the Van Laar equation, the Margules equation and the Wilson equation.

[0012] Furthermore, the threshold requirement of the normalized root mean square deviation is <5%, the threshold requirement of the determination coefficient is >0.99, and the threshold requirement of the absolute mean error is <5%.

[0013] Furthermore, the following formula is used to calculate the first mixed dispersion heat: , in, Disperse heat for the first mix, is the real-time heat flux on the reactor wall, S is the heat exchange inner wall area of ​​the reactor, t is the mixing dispersion heat flow measurement time, t 0 is the starting time of heat flow measurement, t 1 is the end time of heat flow measurement.

[0014] Further, the correction of the heat of the reaction process by using the second mixed dispersion heat is based on the following formula: , in, is the measured value of heat during the reaction after material mixing. Dissipate heat for the second mix.

[0015] The advantages of the present invention compared with the prior art are: The present invention measures the thermal effect brought about by the mixing and dispersion of initial materials and subsequent feeds in a chemical reaction process, and determines a thermodynamic model that can be used for correction by fitting different thermodynamic models according to the mixing and dispersion of the reaction materials. Finally, the thermal effect of the reaction process after the material mixing is corrected by the selected thermodynamic model, thereby effectively improving the authenticity and reliability of the monitoring parameters of the chemical reaction process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the process for measuring and analyzing the thermal effect of material mixing and dispersion. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the embodiments, but are not intended to limit the present invention.

[0018] The measurement and analysis system for the thermal effect of material mixing and dispersion involved in this embodiment includes a feeding module, a first calculation module, a fitting module, a second calculation module and a correction module.

[0019] Among them, the feeding module is used to add the base material and the feed material into the reactor for mixing; The first calculation module is used to measure the heat flow data of the reactor wall during the mixing process and calculate the first mixing dispersion heat; The fitting module uses several thermodynamic models to fit the calculated first mixed dispersion heat, the mole fraction of the base material in the mixed material, and the mole fraction of the added material in the mixed material, and selects a thermodynamic model whose normalized root mean square deviation, coefficient of determination, and absolute mean error of the fitting results all meet the threshold requirements; The second calculation module is used to calculate the second mixed dispersion heat based on the selected thermodynamic model; The correction module uses the second mixed dispersion heat to correct the heat of the reaction process after the materials are mixed.

[0020] Please combine Figure 1 As shown, the specific measurement and analysis method implemented based on the measurement and analysis system is as follows: By exchanging the order of feeding and bottom feeding, two mixing heat test experiments were carried out respectively. In each mixing heat test experiment, the feeding was completed in 3 to 7 times, and the feeding rate could be determined according to the number of feedings. At the same time, the heat flux data of the reactor wall was recorded in real time by the heat flux sensor, and the first mixing dispersion heat was calculated according to the heat exchange inner wall area of ​​the reactor, and the formula was: First mix to disperse the heat: (1) in, is the real-time power of heat transfer on the reactor wall, in W, t is the mixing dispersion heat flow measurement time, t 0 is the starting time of heat flow measurement, t 1 is the end time of heat flow measurement.

[0021] (2) in, is the real-time heat flux of the reactor wall, in W / m 2 , S is the heat exchange inner wall area of ​​the reactor, in m 2 .

[0022] The above mixed dispersion heat is introduced into three different thermodynamic models for fitting. Model 1 is the Van Laar equation (Formula 3), model 2 is the Margules equation (Formula 4), and model 3 is the Wilson equation (Formula 5).

[0023] (3) (4) (5) The normalized root-mean-square deviation (NRMSD), squared correlation coefficient (R-square), and absolute average deviation (AAD) of the fitting results are used to analyze the applicability of different models. When the three conditions of NRMSD < 5%, R-square > 0.99, and AAD < 5% are met at the same time, it is believed that the thermodynamic model can better correlate the heat of material mixing and dispersion in the system.

[0024] The second mixed dispersion heat is calculated using a thermodynamic model that meets the above three conditions , and then the heat of the reaction process after the materials are mixed is modified by the following formula: (6) in is the measured value of heat during the reaction after material mixing. The second mixed heat dissipation, where Measured by heat flow method or heat flux sensor.

[0025] A chemical reaction process involves two materials, namely material A and material B. The first group of experiments: material A is the base material, material B is the subsequent feed, and material A and material B with a molar ratio of 1:1 are weighed respectively. At a jacket temperature of 25°C and a stirring rate of 300 rpm, material A is first added to the reactor at one time, and then an equal number of moles of material B is added to the reactor by a feed pump in 5 times, with an interval of 20 min between each addition, so that it is mixed with material A. The second group of experiments: material B is the base material, material A is the subsequent feed, and material A and material B with a molar ratio of 1:1 are weighed respectively. At a jacket temperature of 25°C and a stirring rate of 300 rpm, material B is first added to the reactor at one time, and then an equal number of moles of material A is added to the reactor by a feed pump in 5 times, with an interval of 20 min between each addition, so that it is mixed with material B. The heat flow during the two groups of experiments was recorded. Table 1 shows the first mixed dispersion heat calculated based on the experimental results.

[0026] Table 1 Calculation results of the first mixed dispersion heat

[0027] According to the first mixed dispersion heat, the mixed heat measurement data was fitted using model one, and the results are shown in Table 2.

[0028] Table 2 Thermodynamic model fitting results

[0029] According to the fitting results, the R-square value of model one is 0.9813, which does not meet the discrimination requirements. Model two is used to fit the mixed heat measurement data. According to the fitting results, the NRMSD value of model two is 5.06%, which does not meet the discrimination requirements. Model three is used to fit the mixed heat measurement data. According to the fitting results, the NRMSD, R-square, and AAD values ​​of model three all meet the discrimination conditions. Therefore, the fitting results of model three can be used to make real-time corrections to the heat of the reaction process after material mixing.

Claims

1. A method for measuring and analyzing the thermal effect of material mixing and dispersion, characterized in that: Includes steps: Adding the base material and the feed material into the reactor for mixing; During the mixing process, the heat flow data of the reactor wall is measured and the first mixing dispersion heat is calculated; Using several thermodynamic models to fit the calculated first mixed dispersion heat, the mole fraction of the base material in the mixed material, and the mole fraction of the added material in the mixed material, and selecting a thermodynamic model whose normalized root mean square deviation, coefficient of determination, and absolute mean error of the fitting results all meet the threshold requirements; calculating a second mixed dispersion heat based on a selected thermodynamic model; The second mixing and dispersing heat is used to correct the heat of the reaction process after the materials are mixed.

2. The method for measuring and analyzing the thermal effect of material mixing and dispersion according to claim 1 is characterized in that: The thermodynamic models include the Van Laar equation, the Margules equation and the Wilson equation.

3. The method for measuring and analyzing the thermal effect of material mixing and dispersion according to claim 1 is characterized in that: The threshold requirement of the normalized root mean square deviation is <5%, the threshold requirement of the determination coefficient is >0.99, and the threshold requirement of the absolute mean error is <5%.

4. The method for measuring and analyzing the thermal effect of material mixing and dispersion according to claim 1 is characterized in that: The following formula is used to calculate the first mixed dispersion heat ， in, Disperse heat for the first mix, is the real-time heat flux on the reactor wall, S is the heat exchange inner wall area of ​​the reactor, t is the mixing dispersion heat flow measurement time, t 0 is the starting time of heat flow measurement, t 1 is the end time of heat flow measurement.

5. The method for measuring and analyzing the thermal effect of material mixing and dispersion according to claim 1 is characterized in that: The use of the second mixed dispersion heat to correct the heat of the reaction process after the material mixing is based on the following formula: ， in, is the measured value of heat during the reaction after material mixing. Dissipate heat for the second mix.

6. A measurement and analysis system for the thermal effect of material mixing and dispersion, characterized in that: It includes a feeding module, a first calculation module, a fitting module, a second calculation module and a correction module; The feeding module is used to add the base material and the feed material into the reactor for mixing; The first calculation module is used to measure the heat flow data of the reactor wall during the mixing process and calculate the first mixing dispersion heat; The fitting module uses several thermodynamic models to fit the calculated first mixed dispersion heat, the molar fraction of the base material in the mixed material, and the molar fraction of the added material in the mixed material, and selects a thermodynamic model whose normalized root mean square deviation, coefficient of determination, and absolute mean error of the fitting results all meet the threshold requirements; The second calculation module is used to calculate the second mixed dispersion heat based on the selected thermodynamic model; The correction module uses the second mixed dispersion heat to correct the heat of the reaction process after the materials are mixed.

7. The measuring and analyzing system for the thermal effect of material mixing and dispersion according to claim 6 is characterized in that: The thermodynamic models include the Van Laar equation, the Margules equation and the Wilson equation.

8. The measuring and analyzing system for the thermal effect of material mixing and dispersion according to claim 6 is characterized in that: The threshold requirement of the normalized root mean square deviation is <5%, the threshold requirement of the determination coefficient is >0.99, and the threshold requirement of the absolute mean error is <5%.

9. The measuring and analyzing system for the thermal effect of material mixing and dispersion according to claim 6 is characterized in that: The following formula is used to calculate the first mixed dispersion heat ， in, Disperse heat for the first mix, is the real-time heat flux on the reactor wall, S is the heat exchange inner wall area of ​​the reactor, t is the mixing dispersion heat flow measurement time, t 0 is the starting time of heat flow measurement, t 1 is the end time of heat flow measurement.

10. The measuring and analyzing system for the thermal effect of material mixing and dispersion according to claim 6, characterized in that: The use of the second mixed dispersion heat to correct the heat of the reaction process after the material mixing is based on the following formula: ， in, is the measured value of heat during the reaction after material mixing. Dissipate heat for the second mix.

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