Soft measurement method for activity of bisphenol A cocatalyst

Abstract

The invention relates to a soft measurement method for activity of a bisphenol A cocatalyst. The soft measurement method comprises the following steps: a, recording inlet temperature, outlet temperature and flow parameters when the catalyst is initially filled; b, reference parameters are set, and initial parameters are fitted; c, on-site actual operation process parameters are collected, and the ratio of the parameters to the reference parameters is obtained; d, according to the theoretical temperature rise relation function, calculating to obtain theoretical temperature rise under 100% catalyst activity; e, performing back calculation on the catalyst amount according to the actual temperature rise and the theoretical temperature rise to obtain an activity percentage; f, setting an acetone load upper limit according to the activity percentage. The method has the advantages that the self condition of the catalyst is taken as a benchmark, the influence of temperature, flow and composition on the conversion rate is eliminated through reaction kinetics, only the effective mass of the catalyst is calculated, the activity percentage is obtained, the method has the advantages of data stability and trend controllability, and the method is not affected by the full-life-cycle use environment of the catalyst; and real-time calculation and monitoring of the activity of the bisphenol A cocatalyst are realized.

Description

Technical Field

[0001] The invention relates to a soft measurement method for the activity of a bisphenol A co-catalyst, and belongs to the field of online measurement. Background Art

[0002] Bisphenol A is widely used in materials, medicine, additives and other fields. Currently, bisphenol A is obtained by reacting phenol and acetone on an ion exchange resin catalyst. The reaction conditions are generally an excess of phenol, a phenol-acetone ratio generally controlled between 8-10, a reaction temperature of 50-70°C, and the reaction consumes as much acetone as possible to reduce material loss and purification energy consumption in the process.

[0003] The bed life of bisphenol A resin catalyst is relatively short. As the catalyst activity decreases over time, the acetone feed rate needs to be reduced accordingly. This process generally lasts for more than one year. In addition, the activity of the catalyst is also affected by factors such as the reaction feed temperature, phenol-acetone ratio, and acetone load. There is no suitable way to evaluate the specific activity of the currently operating catalyst. Blind replacement may result in waste of catalyst or the device may operate under high energy and material consumption conditions for a long time.

[0004] The current soft measurement technology is based on data modeling. Patent CN2009101387623A discloses a soft measurement model based on historical data and operating parameters. The existing catalyst activity is calculated according to the operating time, acetone flow, temperature, and phenol-to-ketone ratio, and the prediction achieves good results. However, changes in the load and operating conditions of the actual factory may cause the model's prediction accuracy to decrease in the middle and late stages of the catalyst, resulting in a waste of catalyst. Summary of the invention

[0005] In order to overcome the defects of the prior art, the present invention provides a soft measurement method for the activity of bisphenol A co-catalyst, which can accurately calculate the evaluation method of the reaction activity of bisphenol A co-catalyst and apply it to real-time calculation, so as to adjust the production load according to the catalyst activity and extend the catalyst service life, reduce the increase in recovery energy consumption caused by insufficient catalyst activity and the waste caused by premature replacement due to insufficient catalyst utilization.

[0006] The technical solution of the present invention is: a soft measurement method for the activity of bisphenol A co-catalyst, comprising the following steps:

[0007] a. Record the inlet temperature, outlet temperature and flow parameters of the catalyst when initially loaded;

[0008] b. Setting the benchmark parameters Duty0, ratio0, Tin0, and fitting the initial parameters to obtain the theoretical temperature rise relationship function corresponding to 100% catalyst activity;

[0009] c. Collect the actual process parameters on site and compare them with the benchmark parameters;

[0010] d. According to the theoretical temperature rise relationship function, the theoretical temperature rise under 100% catalyst activity is calculated;

[0011] e. Back-calculate the amount of catalyst based on the actual temperature rise and the theoretical temperature rise to obtain the activity percentage;

[0012] f. Set the upper limit of acetone load according to the activity percentage.

[0013] In the step a, the accuracy of the thermometers installed at the inlet and outlet is not less than 0.1°C, and the composition of acetone, phenol and bisphenol A at the inlet of the reactor is read by an online spectrometer.

[0014] The specific step b is as follows: the theoretical temperature rise relationship function is a function of feed load, phenol-ketone ratio, and inlet temperature, ΔT = p0 + f (Duty, ratio, T in ), where p0 is the correction coefficient, Duty is the acetone feed flow rate, ratio is the flow ratio of phenol to acetone, Tin refers to the reactor inlet temperature, ΔT is the reactor inlet and outlet temperature difference. During the initial parameter fitting, only p0 in the temperature rise equation is fitted.

[0015] The activity percentage in step e is calculated by the following function:

[0016] Where α is the catalyst activity, ΔT real is the actual inlet and outlet temperature difference of the reactor on site, and ΔT is the theoretical inlet and outlet temperature difference of the reactor.

[0017] The upper limit of acetone loading and the relative activity of the catalyst satisfy the function:

[0018] Among them, Duty is the upper limit of acetone load, and Duty0 is the reference value of acetone load.

[0019] The advantages of the present invention are:

[0020] Taking the catalyst itself as a benchmark, the effects of temperature, flow rate, and composition on the conversion rate are eliminated through reaction kinetics, and only the effective mass of the catalyst is calculated to obtain the activity percentage. This method has the advantages of stable data and controllable trends, and is not restricted by factors such as production load and raw material impurity content during the catalyst's entire life cycle. It can realize real-time calculation and monitoring of the activity of bisphenol A co-catalyst. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, these embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of protection of the present invention.

[0022] The present invention relates to a soft measurement method for the activity of a bisphenol A promoter, comprising the following steps:

[0023] a. Record the inlet temperature, outlet temperature and flow parameters of the catalyst when initially loaded;

[0024] b. Setting the benchmark parameters Duty0, ratio0, Tin0, and fitting the initial parameters to obtain the theoretical temperature rise relationship function corresponding to 100% catalyst activity;

[0025] c. Collect the actual process parameters on site and compare them with the benchmark parameters;

[0026] d. According to the theoretical temperature rise relationship function, the theoretical temperature rise under 100% catalyst activity is calculated;

[0027] e. Back-calculate the amount of catalyst according to the actual temperature rise to obtain the activity percentage;

[0028] f. Set the upper limit of acetone load according to the activity percentage.

[0029] In the step a, the accuracy of the thermometers installed at the inlet and outlet is not less than 0.1°C, and the composition of acetone, phenol and bisphenol A at the inlet of the reactor is read by an online spectrometer.

[0030] The specific step b is as follows: the theoretical temperature rise relationship function is a function of feed load, phenol-ketone ratio, and inlet temperature, ΔT = p0 + f (Duty, ratio, T in ), where p0 is the correction coefficient, Duty is the acetone feed flow rate, ratio is the flow ratio of phenol to acetone, Tin refers to the reactor inlet temperature, ΔT is the reactor inlet and outlet temperature difference. During the initial parameter fitting, only p0 in the temperature rise equation is fitted.

[0031] The activity percentage in step e is calculated by the following function: Where α is the catalyst activity, ΔT real is the actual inlet and outlet temperature difference of the reactor on site, and ΔT is the theoretical inlet and outlet temperature difference of the reactor.

[0032] The upper limit of acetone loading and the relative activity of the catalyst satisfy the function:

[0033] Among them, Duty is the upper limit of acetone load, and Duty0 is the reference value of acetone load.

[0034] The present invention relates to a soft measurement method for the activity of a bisphenol A promoter, and the working principle thereof is as follows: initial parameter recording (step a):

[0035] Record the inlet temperature, outlet temperature and flow rate parameters when the catalyst is initially loaded. These parameters are the basis for subsequent calculations and comparisons.

[0036] Thermometers with an accuracy of not less than 0.1°C are set at the inlet and outlet to ensure the accuracy of temperature measurement.

[0037] An online spectrometer was used to read the composition of acetone, phenol, and bisphenol A at the reactor inlet to ensure the accuracy of the feed composition.

[0038] Benchmark parameter setting and theoretical temperature rise relationship function fitting (step b):

[0039] Set the benchmark parameters Duty0 (base value of acetone feed flow), ratio0 (base value of phenol to acetone flow ratio), and Tin0 (base value of reactor inlet temperature).

[0040] The initial parameters are fitted to obtain the theoretical temperature rise relationship function corresponding to 100% catalyst activity. This function is a function of feed load, phenol-ketone ratio, and inlet temperature. The correction coefficient p0 is determined by parameter fitting.

[0041] On-site actual operation process parameter collection and ratio calculation (step c):

[0042] The actual operating process parameters on site are collected and compared with the benchmark parameters to evaluate the difference between the actual operating status and the benchmark status.

[0043] Theoretical temperature rise calculation (step d):

[0044] According to the theoretical temperature rise relationship function, the theoretical temperature rise under 100% catalyst activity is calculated. The activity percentage is calculated by back-calculating the catalyst amount (step e):

[0045] The catalyst amount is back-calculated based on the actual temperature rise to obtain the activity percentage. The activity percentage is calculated using a specific function that involves the ratio of the actual inlet and outlet temperature difference of the reactor to the theoretical inlet and outlet temperature difference of the reactor.

[0046] Acetone load upper limit setting (step f):

[0047] The upper limit of acetone loading is set according to the activity percentage to ensure that the reaction is carried out at the optimal activity. The upper limit of acetone loading and the relative activity of the catalyst satisfy a specific functional relationship.

[0048] Example:

[0049] The process parameters recorded during the initial loading were: acetone feed rate of 1600 kg / h, phenol-acetone ratio of 13.7, inlet temperature of 56.54 °C, and outlet temperature of 77.42 °C. Based on the functional relationship: ΔT = p0 + f (Duty, ratio, T in ), and parameter fitting was performed to obtain p0 as 24.19.

[0050] After being put into real-time operation, the acetone feed rate was 1300 kg / h, the phenol-acetone ratio was 18.7, the inlet temperature was 56°C, and the outlet temperature was 76.66°C. According to the fitted function relationship ΔT=p0+f(Duty, ratio, T in )

[0051] The calculated reference temperature difference ΔT for 100% activity is 24.68°C, and the actual temperature difference ΔT real is 20.66℃, according to the functional relationship The catalyst activity was obtained to be 64.5%. The maximum acetone load was further calculated, and the Duty was 901 kg / h. At this time, the acetone content at the reactor outlet was not higher than 0.55%.

[0052] The advantages of the present invention are:

[0053] Precise measurement and control: High-precision thermometers and online spectrometers ensure measurement accuracy, thereby improving the reliability of catalyst activity measurements.

[0054] Real-time monitoring and adjustment: Through real-time collection and ratio calculation of the actual operating process parameters on site, the process parameters can be adjusted in time to adapt to changes in catalyst activity.

[0055] Optimize catalyst usage: By calculating the catalyst activity percentage and setting the upper limit of acetone load, the catalyst usage efficiency can be optimized and the catalyst service life can be extended.

[0056] Improve production efficiency: By precisely controlling the upper limit of acetone loading, the reaction is ensured to proceed at the optimal activity, thereby improving production efficiency and product quality.

[0057] Reduce energy consumption and costs: By optimizing catalyst activity measurement and control, unnecessary energy consumption and raw material waste can be reduced, thereby reducing production costs.

[0058] In summary, the present invention realizes soft measurement of the activity of bisphenol A co-catalyst through a series of precise measurement and calculation steps, which has significant economic and environmental benefits.

[0059] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A soft measurement method for bisphenol A co-catalyst activity, characterized in that: The following steps are involved: a. Record the inlet temperature, outlet temperature and flow parameters of the catalyst when initially loaded; b. Setting the benchmark parameters Duty0, ratio0, Tin0, and fitting the initial parameters to obtain the theoretical temperature rise relationship function corresponding to 100% catalyst activity; c. Collect the actual process parameters on site and compare them with the benchmark parameters; d. According to the theoretical temperature rise relationship function, the theoretical temperature rise under 100% catalyst activity is calculated; e. Back-calculate the amount of catalyst based on the actual temperature rise and the theoretical temperature rise to obtain the activity percentage; f. Set the upper limit of acetone load according to the activity percentage.

2. The soft measurement method for bisphenol A promoter activity according to claim 1, characterized in that: In the step a, the accuracy of the thermometers installed at the inlet and outlet is not less than 0.1°C, and the composition of acetone, phenol and bisphenol A at the inlet of the reactor is read by an online spectrometer.

3. The soft measurement method for bisphenol A promoter activity according to claim 2, characterized in that: The specific step b is as follows: the theoretical temperature rise relationship function is a function of feed load, phenol-ketone ratio, and inlet temperature, ΔT = p0 + f (Duty, ratio, T in ), where p0 is the correction coefficient, Duty is the acetone feed flow rate, ratio is the flow ratio of phenol to acetone, T in Refers to the reactor inlet temperature, ΔT is the reactor inlet and outlet temperature difference. During the initial parameter fitting, only p0 in the temperature rise equation is fitted.

4. The soft measurement method for bisphenol A co-catalyst activity according to claim 3, characterized in that: The activity percentage in step e is calculated by the following function: Where α is the catalyst activity, ΔT real is the actual inlet and outlet temperature difference of the reactor on site, and ΔT is the theoretical inlet and outlet temperature difference of the reactor.

5. The soft measurement method for bisphenol A co-catalyst activity according to claim 4, characterized in that: The upper limit of acetone loading and the relative activity of the catalyst satisfy the function: Among them, Duty is the upper limit of acetone load, and Duty0 is the reference value of acetone load.

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