Method and system for constant temperature control in paste resin polymerization process

Abstract

The invention relates to the technical field of temperature control, in particular to a method and a system for constant temperature control in a paste resin polymerization process. A database; the temperature prediction module is used for predicting the temperature of a future target time point in the polymerization kettle according to the temperatures of a plurality of preset point positions in the polymerization kettle; the data processing module is used for determining the temperature adjustment amount in the circulating pump according to the predicted temperature and the current temperature of the outlet of the circulating pump and determining a valve adjustment mode according to the temperature adjustment amount; the valve adjusting module is used for adjusting the valve opening degrees of the cold water valve, the hot water valve and the circulating water valve according to the valve adjusting mode determined by the data processing module; and the correction module is used for correcting the opening degree of each valve. According to the invention, the opening degree of the valve can be timely adjusted and corrected according to the reaction change in the polymerization kettle, so that the constant temperature control in the polymerization kettle is realized, the stability of the polymerization process is improved, and the energy waste caused by excessive adjustment can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of temperature control, and in particular to a method and system for constant temperature control in a paste resin polymerization process. Background Art

[0002] The paste resin polymerization process refers to adding initiators, vinyl chloride and other raw materials into a polymerization kettle in a certain ratio, so that the raw materials react in the polymerization kettle to produce paste resin products. After the reaction starts, it is necessary to control the heat exchange medium of different temperatures in the heat exchange coil of the polymerization kettle to provide heat and take away excess heat to ensure the stability of the polymerization reaction temperature.

[0003] During the production process of paste resin, due to the long polymerization cycle of paste resin and the uneven heat release during the reaction, the existing control system is difficult to achieve accurate utilization of heat exchange media in the constant temperature reaction control stage of the polymerization kettle. The jacket heat exchange medium is over-adjusted, and frequent switching between the cold source, heat source and circulating water is required to meet the material temperature balance. There is a large energy difference between the above three heat exchange media, and different corrosion inhibitors are used to slow down equipment corrosion. Frequent switching leads to mixing of cold and hot sources, resulting in energy waste. Temperature fluctuations will also affect the quality of products in production.

[0004] Chinese patent publication number CN108268070A discloses a thermostatic control system for thermostatic equipment, including a temperature sensor, a refrigeration device, a heating device, a control terminal, a processing module, a judgment module and a communication module. The thermostatic control system provided by the present invention uses a temperature sensor to monitor the temperature of the thermostatic equipment in real time and compare it with the upper and lower limits of the preset temperature range. When the monitored temperature is higher than the upper limit of the preset temperature range, the refrigeration device is started to cool the thermostatic equipment; when the monitored temperature is lower than the lower limit of the preset temperature range, the heating device is started to heat the thermostatic equipment. The control terminal can remotely modify various working parameters and control cooling or heating. If the monitored temperature exceeds the preset temperature range, the monitored temperature information will be transmitted to the control terminal, which is convenient for the staff to grasp the real-time situation.

[0005] It can be seen that the above invention has the following problems: the control process is single, and the temperature is lowered or raised only based on the comparison between the temperature and the upper and lower limits of the preset temperature range, and the system stability is not high. Summary of the invention

[0006] To this end, the present invention provides a method and system for constant temperature control of a paste resin polymerization process, so as to overcome the problem of relatively low system stability caused by a single control process in the prior art.

[0007] To achieve the above object, on the one hand, the present invention provides a system for constant temperature control of a paste resin polymerization process, comprising:

[0008] A data monitoring module, which is used to monitor in real time the temperature of several preset points in the polymerization kettle, the temperature of the outlet of the circulation pump, and the gas pressure in the polymerization kettle;

[0009] A database, which is connected to the data monitoring module and is used to store the temperature and air pressure data monitored by the data monitoring module and the corresponding monitoring time points;

[0010] A temperature prediction module, which is connected to the database and is used to determine whether the pressure change in the polymerization kettle meets the preset standard, and based on the result of the determination that the pressure changes in the polymerization kettle meet the preset standard, predict the temperature of the polymerization kettle at a future target time point according to the temperatures of several preset points in the polymerization kettle to obtain a predicted temperature;

[0011] a data processing module, which is connected to the temperature prediction module and the database respectively, and is used to determine the temperature adjustment amount in the circulation pump according to the predicted temperature and the current temperature of the circulation pump outlet, and determine the valve adjustment method according to the temperature adjustment amount, including the adjustment method of the cold water valve, the hot water valve and the circulating water valve;

[0012] A valve adjustment module, which is connected to the data processing module and is used to adjust the valve openings of the cold water valve, the hot water valve and the circulating water valve respectively according to the valve adjustment mode determined by the data processing module;

[0013] A correction module is connected to the database and is used to correct the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time in the future.

[0014] Furthermore, the temperature prediction module comprises:

[0015] An air pressure determination submodule, which is connected to the database and is used to determine whether the air pressure change in the polymerization kettle meets a preset standard; the preset standard is that the air pressure change in the polymerization kettle per unit time is greater than a preset change threshold;

[0016] An early warning temperature determination submodule, which is connected to the air pressure determination submodule and the database, respectively, and is used to determine the early warning temperature according to the temperature of each preset point in the polymerization kettle when the air pressure determination submodule determines that the air pressure change in the polymerization kettle meets the preset standard;

[0017] The predicted temperature determination submodule is connected to the early warning temperature determination submodule and is used to predict the temperature at a future target time point in the polymerization kettle according to the historical temperature of the preset point corresponding to the early warning temperature to obtain the predicted temperature.

[0018] Furthermore, the data processing module includes:

[0019] A heat exchange temperature determination submodule, which is connected to the temperature prediction module and is used to determine the heat exchange temperature according to the predicted temperature and the standard reaction temperature;

[0020] a temperature adjustment amount determination submodule, which is connected to the heat exchange temperature determination submodule and the database respectively, and is used to determine the temperature adjustment amount in the circulation pump according to the heat exchange temperature and the current temperature of the circulation pump outlet;

[0021] The valve adjustment mode determination submodule is connected to the temperature adjustment amount determination submodule, and is used to compare the temperature adjustment amount with a preset adjustment amount threshold, and determine the valve adjustment mode according to the comparison result, including the adjustment mode of the cold water valve, hot water valve and circulating water valve.

[0022] Furthermore, the correction module includes:

[0023] A temperature analysis submodule, which is connected to the database and is used to analyze the temperature changes of several preset points in the polymerization kettle within a preset time period in the future to determine the temperature change characteristic value of each preset point;

[0024] A data comparison submodule, which is connected to the temperature analysis submodule, and is used to compare each of the temperature change characteristic values ​​with a preset temperature characteristic value, and determine a target temperature change characteristic value according to the comparison result;

[0025] The correction submodule is connected to the data comparison submodule, and is used to determine the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point, and compare the target temperature with the predicted temperature, and correct the opening of each valve according to the comparison result.

[0026] Furthermore, the correction submodule includes:

[0027] A correction analysis unit connected to the data comparison submodule, for comparing the preset point corresponding to the target temperature change characteristic value with the preset point corresponding to the predicted temperature, and determining the target temperature according to the comparison result;

[0028] The correction unit is connected to the correction analysis unit and is used to compare the target temperature with the predicted temperature and correct the opening of each valve according to the comparison result.

[0029] Furthermore, the correction analysis unit determines the target temperature according to the comparison result, including:

[0030] The correction analysis unit determines the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point as the target temperature based on the comparison result that the preset point corresponding to the target temperature change characteristic value is consistent with the preset point corresponding to the predicted temperature;

[0031] The correction analysis unit determines the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point and the preset temperature coefficient based on the comparison result that the preset point corresponding to the target temperature change characteristic value is inconsistent with the preset point corresponding to the predicted temperature.

[0032] Furthermore, the warning temperature determination submodule determines the temperature of the preset point corresponding to the maximum difference between the temperature of each preset point in the polymerization kettle and the preset temperature threshold as the warning temperature based on the result that the air pressure judgment submodule determines that the air pressure change in the polymerization kettle meets the preset standard.

[0033] Further, the valve adjustment mode determination submodule determines the valve adjustment mode as the first adjustment mode or the second adjustment mode based on the comparison result that the temperature adjustment amount is less than 0 and the comparison result between the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference;

[0034] The valve adjustment mode determination submodule determines that the valve adjustment mode is the third adjustment mode or the fourth adjustment mode based on the comparison result that the temperature adjustment amount is greater than 0 and the comparison result of the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference;

[0035] Among them, the first adjustment method is to adjust the valve opening of the cold water valve and the circulating water valve, and keep the hot water valve closed; the second adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed; the third adjustment method is to adjust the valve opening of the hot water valve and the circulating water valve, and keep the cold water valve closed; the fourth adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed.

[0036] Furthermore, the temperature analysis submodule determines the temperature change characteristic value of each preset point according to the ratio of the temperature difference of the next adjacent time point to the temperature difference of the previous adjacent time point of each preset point in the polymerization kettle within the future preset time period.

[0037] On the other hand, the present invention also provides a constant temperature control method, comprising:

[0038] Step S1, obtaining the temperatures of several preset points in the polymerization kettle, the temperature of the outlet of the circulation pump, and the gas pressure in the polymerization kettle;

[0039] Step S2, predicting the temperature at a future target time point in the polymerization kettle according to the temperature and air pressure data of several preset points in the polymerization kettle to obtain a predicted temperature;

[0040] Step S3, determining a temperature adjustment amount in the circulation pump according to the predicted temperature and the current temperature at the outlet of the circulation pump, and determining a valve adjustment method according to the temperature adjustment amount, including an adjustment method of a cold water valve, a hot water valve, and a circulating water valve;

[0041] Step S4, adjusting the valve openings of the cold water valve, the hot water valve and the circulating water valve respectively according to the valve adjustment method;

[0042] Step S5, correcting the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time period in the future.

[0043] Compared with the prior art, the beneficial effect of the present invention is that the temperature prediction module of the present invention can determine the reaction changes in the polymerization kettle in real time by judging according to the changes in the air pressure in the polymerization kettle. By predicting the temperature at the future target time point in the polymerization kettle, it can provide a basis for subsequent adjustment of the valve to avoid energy waste caused by multiple adjustments. The data processing module determines the temperature adjustment amount according to the predicted temperature and the current temperature of the circulation pump outlet, and determines the valve adjustment method according to the temperature adjustment amount, which can improve the accuracy of valve adjustment and avoid frequent switching to cause mixing of cold and hot sources, resulting in energy waste. The correction module corrects the opening of each valve according to the temperature changes of several preset points in the polymerization kettle within the future preset time period, which can achieve constant temperature control in the polymerization kettle and improve the stability of the polymerization process.

[0044] Furthermore, the temperature prediction module of the present invention includes an air pressure determination submodule, an early warning temperature determination submodule and a predicted temperature determination submodule. By determining the early warning temperature and predicting the temperature at a future target time point in the polymerization kettle based on the historical temperature of a preset point corresponding to the early warning temperature, the accuracy of temperature prediction can be improved, as well as the prediction efficiency.

[0045] Furthermore, the data processing module of the present invention includes a heat exchange temperature determination submodule, a temperature adjustment amount determination submodule and a valve adjustment mode determination submodule. By determining the heat exchange temperature, the temperature adjustment amount can be accurately determined while avoiding subsequent energy waste caused by multiple adjustments.

[0046] Furthermore, the correction module of the present invention includes a temperature analysis submodule, a data comparison submodule and a correction submodule. By determining the temperature change characteristic value of each preset point, the temperature change situation of each preset point can be accurately reflected. The target temperature change characteristic value determined in this way can reflect the temperature change situation in the polymerization kettle. By correcting the opening of each valve based on the comparison result of the target temperature and the predicted temperature, the accuracy of the adjustment can be improved, and the stability of the constant temperature control in the polymerization kettle can be further ensured.

[0047] Furthermore, the correction submodule of the present invention includes a correction analysis unit and a correction unit. The correction analysis unit determines the target temperature by comparing the preset point corresponding to the target temperature change characteristic value with the preset point corresponding to the predicted temperature, thereby improving the accuracy of the target temperature and thus improving the accuracy of correcting the opening of each valve.

[0048] Furthermore, the valve adjustment mode determination submodule of the present invention determines the valve adjustment mode according to the relationship between the temperature adjustment amount and 0 and a preset adjustment amount threshold, and can achieve constant temperature control in the polymerization kettle according to the energy difference between cold water, hot water and circulating water, thereby avoiding energy waste caused by frequent valve switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a structural block diagram of a system for constant temperature control of a paste resin polymerization process according to an embodiment of the present invention;

[0050] Figure 2 It is a structural block diagram of a temperature prediction module according to an embodiment of the present invention;

[0051] Figure 3 is a structural block diagram of a data processing module according to an embodiment of the present invention;

[0052] Figure 4 It is a structural block diagram of a correction module according to an embodiment of the present invention;

[0053] Figure 5 It is a structural block diagram of the correction submodule according to an embodiment of the present invention;

[0054] Figure 6 This is a flow chart of a method for constant temperature control of a paste resin polymerization process according to an embodiment of the present invention;

[0055] Figure 7 This is a schematic structural diagram of a thermostatic control system for a paste resin polymerization process according to an embodiment of the present invention;

[0056] In the figure: 1. Polymerization kettle; 2. Circulation pump; 3. Circulation pump valve; 4. Hot water valve; 5. Circulation water valve; 6. Cold water valve. DETAILED DESCRIPTION

[0057] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0058] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0059] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0060] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] See also Figure 1 and Figure 7 As shown, Figure 1 This is a structural block diagram of a system for constant temperature control of a paste resin polymerization process according to an embodiment of the present invention; Figure 7 Schematic diagram of the structure of a constant temperature control system for a paste resin polymerization process according to an embodiment of the present invention; in the figure: a polymerization kettle 1; a circulating pump 2; a circulating pump valve 3; a hot water valve 4; a circulating water valve 5; and a cold water valve 6.

[0062] It is understandable that the paste resin polymerization production adopts a micro-suspension production process, and the polymerization kettle reaction process goes through the stages of heating, constant temperature, and tailing. The polymerization process controls the temperature of the heat exchange medium entering the polymerization kettle heat exchange coil by adjusting the usage of the three heat exchange media of hot water, circulating water, and cold water through the hot water valve, circulating water valve, and cold water valve, and then the mixed heat exchange medium is sent to the polymerization kettle coil through the circulating pump. After the heat exchange of the heat exchange medium through the coil in the polymerization kettle, part of it flows back to the circulating pump for reuse, and the rest returns to the water storage tank.

[0063] In the implementation, three heat exchange medium pipelines are transported from the pipeline network outside the boundary area, namely hot water, cold water and circulating water. The heat exchange medium pipelines are connected to the same pipeline after passing through their respective valves and enter the circulation pump 2. There is temperature monitoring at the outlet of the circulation pump 2. The heat exchange medium passes through the circulation pump valve 3 at the outlet of the circulation pump 2 and enters the polymerizer 1 coil. There is temperature monitoring in the polymerizer 1. The heat exchange between the coil and the polymerizer 1 is used to supplement or take away heat to keep the temperature of the polymerizer stable.

[0064] The embodiment of the present invention provides a system for constant temperature control of a paste resin polymerization process, comprising:

[0065] A data monitoring module, which is used to monitor in real time the temperature of several preset points in the polymerization kettle 1, the temperature at the outlet of the circulation pump 2, and the gas pressure in the polymerization kettle 1;

[0066] During implementation, the actual implementers can set the distribution of preset points according to the actual situation or the size of the space in the polymerization kettle. Preferably, a preset point is set at a fixed interval, and the interval value range is set to 1 / 3 to 1 / 5 of the height of the polymerization kettle.

[0067] It is understandable that those skilled in the art know that any method and device capable of monitoring temperature and air pressure in the prior art falls within the protection scope of the present invention and will not be described in detail herein.

[0068] A database, which is connected to the data monitoring module and is used to store the temperature and air pressure data monitored by the data monitoring module and the corresponding monitoring time points;

[0069] A temperature prediction module, which is connected to the database and is used to determine whether the pressure change in the polymerization kettle 1 meets the preset standard, and based on the result of the determination that the pressure meets the preset standard, predict the temperature of the polymerization kettle 1 at a future target time point according to the temperatures of several preset points in the polymerization kettle 1 to obtain a predicted temperature;

[0070] A data processing module, which is connected to the temperature prediction module and the database, respectively, and is used to determine the temperature adjustment amount in the circulation pump 2 according to the predicted temperature and the current temperature at the outlet of the circulation pump 2, and determine the valve adjustment method according to the temperature adjustment amount, including the adjustment methods of the cold water valve 6, the hot water valve 4 and the circulating water valve 5;

[0071] A valve adjustment module, which is connected to the data processing module and is used to adjust the valve openings of the cold water valve 6, the hot water valve 4 and the circulating water valve 5 respectively according to the valve adjustment mode determined by the data processing module;

[0072] A correction module is connected to the database and is used to correct the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time in the future.

[0073] The temperature prediction module of the present invention can determine the reaction changes in the polymerization kettle in real time by judging according to the changes in the air pressure in the polymerization kettle. By predicting the temperature at the future target time point in the polymerization kettle, a basis can be provided for subsequent adjustment of the valve to avoid energy waste caused by multiple adjustments. The data processing module determines the temperature adjustment amount according to the predicted temperature and the current temperature of the circulation pump outlet, and determines the valve adjustment method according to the temperature adjustment amount, which can improve the accuracy of valve adjustment and avoid frequent switching to cause mixing of cold and hot sources, resulting in energy waste. The correction module corrects the opening of each valve according to the temperature changes of several preset points in the polymerization kettle within the future preset time period, which can achieve constant temperature control in the polymerization kettle and improve the stability of the polymerization process.

[0074] See also Figure 2 As shown, it is a structural block diagram of a temperature prediction module according to an embodiment of the present invention; specifically, the temperature prediction module includes:

[0075] An air pressure determination submodule, which is connected to the database and is used to determine whether the air pressure change in the polymerization kettle meets a preset standard; the preset standard is that the air pressure change in the polymerization kettle per unit time is greater than a preset change threshold;

[0076] In implementation, if the change in air pressure in the polymerization kettle per unit time is greater than a preset change threshold, it meets the preset standard; if the change in air pressure in the polymerization kettle per unit time is less than or equal to the preset change threshold, it does not meet the preset standard.

[0077] It can be understood that the actual implementers can set a preset change threshold based on the changes in the air pressure in the polymerization kettle that have passed the qualification test in the historical data. The larger the value of the preset change threshold, the higher the requirement for the change in the air pressure in the polymerization kettle per unit time. Preferably, the preset change threshold value range can be set to 0.1MPa~1MPa.

[0078] An early warning temperature determination submodule, which is connected to the air pressure determination submodule and the database, respectively, and is used to determine the early warning temperature according to the temperature of each preset point in the polymerization kettle when the air pressure determination submodule determines that the air pressure change in the polymerization kettle meets the preset standard;

[0079] Specifically, the warning temperature determination submodule determines the temperature of the preset point corresponding to the maximum difference between the temperature of each preset point in the polymerization kettle and the preset temperature threshold as the warning temperature based on the result that the air pressure determination submodule determines that the air pressure change in the polymerization kettle meets the preset standard.

[0080] It can be understood that the actual implementer of the preset temperature threshold can set the preset temperature threshold according to the actual situation or based on the temperature average of each preset point in the same reaction stage under the same conditions of the polymerization process that has passed the qualification test in historical data. Preferably, the preset temperature threshold value range is set to 50°C ~ 60°C.

[0081] The predicted temperature determination submodule is connected to the early warning temperature determination submodule and is used to predict the temperature at a future target time point in the polymerization kettle according to the historical temperature of the preset point corresponding to the early warning temperature to obtain the predicted temperature.

[0082] It is understandable that when the air pressure change in the polymerization kettle meets the preset standard, the air pressure change in the polymerization kettle is relatively large. At this time, the reaction in the polymerization kettle is violent and the temperature gradually increases. When the warning temperature appears, it indicates that heat exchange is about to or has been required in the polymerization kettle. Therefore, the temperature at the future target time point in the polymerization kettle is predicted based on the historical temperature of the preset point corresponding to the warning temperature, which serves as the basis for subsequent adjustment of each valve.

[0083] Those skilled in the art know that any prediction model in the prior art that can predict temperature falls within the protection scope of the present invention and will not be described in detail here.

[0084] In implementation, the target time point can be set according to the difference between the warning temperature and the preset temperature threshold. If the difference is relatively small, the target time point is set closer. If the difference is relatively large, the target time point can be set farther away. Preferably, the target time point is 5s to 20s after the current time point.

[0085] The temperature prediction module of the present invention includes an air pressure determination submodule, an early warning temperature determination submodule and a predicted temperature determination submodule. By determining the early warning temperature and predicting the temperature at a future target time point in the polymerization kettle based on the historical temperature of a preset point corresponding to the early warning temperature, the accuracy of temperature prediction can be improved, as well as the prediction efficiency.

[0086] See also Figure 3 As shown, it is a structural block diagram of a data processing module according to an embodiment of the present invention; specifically, the data processing module includes:

[0087] A heat exchange temperature determination submodule, which is connected to the temperature prediction module and is used to determine the heat exchange temperature according to the predicted temperature and the standard reaction temperature;

[0088] In implementation, the heat exchange temperature can be determined based on the difference between the predicted temperature and the standard reaction temperature (if the heat exchange temperature is greater than or equal to 0, it means that the predicted temperature is greater than or equal to the standard reaction temperature, and some heat needs to be taken away; if the heat exchange temperature is less than 0, it means that the predicted temperature is less than the standard reaction temperature, and some heat needs to be supplemented).

[0089] It is understandable that the standard reaction temperature is the reaction temperature required for the polymerization process and can be set according to the amount of material and the degree of reaction in the actual reaction process.

[0090] a temperature adjustment amount determination submodule, which is connected to the heat exchange temperature determination submodule and the database respectively, and is used to determine the temperature adjustment amount in the circulation pump according to the heat exchange temperature and the current temperature of the circulation pump outlet;

[0091] In implementation, the temperature adjustment amount in the circulation pump may be determined according to the difference between the current temperature at the circulation pump outlet and the heat exchange temperature.

[0092] The valve adjustment mode determination submodule is connected to the temperature adjustment amount determination submodule, and is used to compare the temperature adjustment amount with a preset adjustment amount threshold, and determine the valve adjustment mode according to the comparison result, including the adjustment mode of the cold water valve, hot water valve and circulating water valve.

[0093] Specifically, the valve adjustment mode determination submodule determines the valve adjustment mode as the first adjustment mode or the second adjustment mode based on the comparison result that the temperature adjustment amount is less than 0 and the comparison result of the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference;

[0094] If the temperature adjustment amount is less than 0, a first adjustment difference is determined according to the difference between the absolute value of the temperature adjustment amount and a preset adjustment amount threshold; if the first adjustment difference is greater than a second preset difference, the valve adjustment mode is determined to be the first adjustment mode; if the first adjustment difference is less than or equal to the second preset difference, the valve adjustment mode is determined to be the second adjustment mode;

[0095] The valve adjustment mode determination submodule determines that the valve adjustment mode is the third adjustment mode or the fourth adjustment mode based on the comparison result that the temperature adjustment amount is greater than 0 and the comparison result of the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference;

[0096] If the temperature adjustment amount is greater than or equal to 0, a second adjustment difference is determined according to the difference between the temperature adjustment amount and a preset adjustment amount threshold; if the second adjustment difference is greater than the second preset difference, the valve adjustment mode is determined to be the third adjustment mode; if the second adjustment difference is less than or equal to the second preset difference, the valve adjustment mode is determined to be the fourth adjustment mode;

[0097] Among them, the first adjustment method is to adjust the valve opening of the cold water valve and the circulating water valve, and keep the hot water valve closed; the second adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed; the third adjustment method is to adjust the valve opening of the hot water valve and the circulating water valve, and keep the cold water valve closed; the fourth adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed.

[0098] During implementation, the temperature adjustment amount is less than 0, indicating that the current temperature at the outlet of the circulating pump is less than the heat exchange temperature, and the heat exchange temperature is greater than or equal to 0. At this time, part of the temperature in the polymerization kettle needs to be taken away, so cold water or circulating water is added for heat exchange; if the first adjustment difference is greater than the second preset difference, it indicates that the temperature adjustment amount is relatively large, that is, the heat exchange temperature is relatively large, and only using circulating water for heat exchange will reduce the heat exchange efficiency and affect the polymerization process, while only using cold water will cause energy waste. Therefore, it is necessary to adjust the valve opening of the cold water valve and the circulating water valve at the same time; if the first adjustment difference is less than or equal to the second preset difference, it indicates that the temperature adjustment amount is relatively small, that is, the heat exchange temperature is relatively small, and only circulating water can be used for heat exchange.

[0099] If the temperature adjustment amount is greater than or equal to 0, it indicates that the current temperature at the outlet of the circulating pump is greater than the heat exchange temperature, or the heat exchange temperature is less than 0. At this time, it is necessary to supplement part of the temperature in the polymerization kettle, and heat exchange is performed by adding hot water or circulating water; if the second adjustment difference is greater than the second preset difference, it indicates that the temperature adjustment amount is relatively large, that is, the heat exchange temperature is relatively large, and only using circulating water for heat exchange will reduce the heat exchange efficiency and affect the polymerization process, while only using hot water will cause energy waste. Therefore, it is necessary to adjust the valve opening of the hot water valve and the circulating water valve at the same time; if the second adjustment difference is less than or equal to the second preset difference, it indicates that the temperature adjustment amount is relatively small, that is, the heat exchange temperature is relatively small, and only circulating water can be used for heat exchange.

[0100] It is understandable that the actual implementer can set the preset adjustment threshold value according to the actual situation or based on the average value of the temperature adjustment amount in the polymerization process that passed the qualification test in the historical data. Preferably, the preset adjustment threshold value is set in the range of 15°C to 25°C. The actual implementer can set the second preset difference value according to the actual situation or based on the average value of the difference between the temperature adjustment amount in the polymerization process that passed the qualification test in the historical data and the preset adjustment threshold value. Preferably, the second preset difference value is set in the range of 10°C to 20°C.

[0101] In implementation, the valve opening can be determined according to the ratio of the temperature adjustment amount to the current temperature of the circulation pump outlet. For example, if the ratio of the temperature adjustment amount to the current temperature of the circulation pump outlet is 1 / 2, then the opening degree of each valve is 1 / 2.

[0102] The valve adjustment mode determination submodule of the present invention determines the valve adjustment mode according to the relationship between the temperature adjustment amount and 0 and the preset adjustment amount threshold, and can achieve constant temperature control in the polymerization kettle according to the energy difference between cold water, hot water and circulating water, thereby avoiding energy waste caused by frequent valve switching.

[0103] The data processing module of the present invention includes a heat exchange temperature determination submodule, a temperature adjustment amount determination submodule and a valve adjustment mode determination submodule. By determining the heat exchange temperature, the temperature adjustment amount can be accurately determined, while avoiding subsequent energy waste caused by multiple adjustments.

[0104] See also Figure 4 As shown, it is a structural block diagram of the correction module of an embodiment of the present invention; specifically, the correction module includes:

[0105] A temperature analysis submodule, which is connected to the database and is used to analyze the temperature changes of several preset points in the polymerization kettle within a preset time period in the future to determine the temperature change characteristic value of each preset point;

[0106] In implementation, a preset duration can be set according to the target time point, and the duration from the current time point to the target time point is greater than the preset duration. Preferably, the preset duration value range can be set to 3s to 5s.

[0107] Specifically, the temperature analysis submodule determines the temperature change characteristic value of each preset point according to the ratio of the temperature difference of the next adjacent time point to the temperature difference of the previous adjacent time point of each preset point in the polymerization kettle within the future preset time period.

[0108] A data comparison submodule, which is connected to the temperature analysis submodule, and is used to compare each of the temperature change characteristic values ​​with a preset temperature characteristic value, and determine a target temperature change characteristic value according to the comparison result;

[0109] In implementation, the maximum difference between each of the temperature change characteristic values ​​and a preset temperature characteristic value is determined as the target temperature change characteristic value.

[0110] In implementation, actual implementers can set preset temperature characteristic values ​​according to actual conditions or based on the average of temperature change characteristic values ​​determined in the polymerization process that has passed qualification inspection in historical data. Preferably, the target temperature change characteristic value range is set to 1 to 3.

[0111] The correction submodule is connected to the data comparison submodule, and is used to determine the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point, and compare the target temperature with the predicted temperature, and correct the opening of each valve according to the comparison result.

[0112] See also Figure 3 As shown, it is a structural block diagram of the correction submodule of an embodiment of the present invention; specifically, the correction submodule includes:

[0113] A correction analysis unit connected to the data comparison submodule, for comparing the preset point corresponding to the target temperature change characteristic value with the preset point corresponding to the predicted temperature, and determining the target temperature according to the comparison result;

[0114] Specifically, the correction analysis unit determines the target temperature according to the comparison result, including:

[0115] The correction analysis unit determines the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point as the target temperature based on the comparison result that the preset point corresponding to the target temperature change characteristic value is consistent with the preset point corresponding to the predicted temperature;

[0116] The correction analysis unit determines the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point and the preset temperature coefficient based on the comparison result that the preset point corresponding to the target temperature change characteristic value is inconsistent with the preset point corresponding to the predicted temperature.

[0117] In implementation, the target temperature is determined according to the sum of the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point and the preset temperature coefficient.

[0118] It can be understood that the preset temperature coefficient can be set according to the product of the temperature change of each preset point and the ratio of the distance between each preset point to the total height of the polymerization kettle. For example, the temperature change between the first preset point and the second preset point is 10°C, and the distance between the first preset point and the second preset point is 1 / 10 of the total height of the polymerization kettle. Then the temperature coefficient corresponding to the first preset point and the second preset point is 10×1 / 10=1°C.

[0119] The correction unit is connected to the correction analysis unit and is used to compare the target temperature with the predicted temperature and correct the opening of each valve according to the comparison result.

[0120] In implementation, the opening of each valve is determined according to the ratio of the difference between the target temperature and the predicted temperature to the predicted temperature. For example, if the ratio of the difference between the target temperature and the predicted temperature to the predicted temperature is 1 / 2, the opening degree of each valve is 1 / 2.

[0121] The correction module of the present invention includes a temperature analysis submodule, a data comparison submodule and a correction submodule. By determining the temperature change characteristic value of each preset point, the temperature change situation of each preset point can be accurately reflected. The target temperature change characteristic value determined in this way can reflect the temperature change situation in the polymerization kettle. By correcting the opening of each valve through the comparison result of the target temperature and the predicted temperature, the accuracy of adjustment can be improved, and the stability of constant temperature control in the polymerization kettle can be further guaranteed.

[0122] See also Figure 6 As shown, it is a flow chart of a method for constant temperature control of a paste resin polymerization process according to an embodiment of the present invention; the present invention also provides a constant temperature control method, comprising:

[0123] Step S1, obtaining the temperatures of several preset points in the polymerization kettle, the temperature of the outlet of the circulation pump, and the gas pressure in the polymerization kettle;

[0124] Step S2, predicting the temperature at a future target time point in the polymerization kettle according to the temperature and air pressure data of several preset points in the polymerization kettle to obtain a predicted temperature;

[0125] Step S3, determining a temperature adjustment amount in the circulation pump according to the predicted temperature and the current temperature at the outlet of the circulation pump, and determining a valve adjustment method according to the temperature adjustment amount, including an adjustment method of a cold water valve, a hot water valve, and a circulating water valve;

[0126] Step S4, adjusting the valve openings of the cold water valve, the hot water valve and the circulating water valve respectively according to the valve adjustment method;

[0127] Step S5, correcting the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time period in the future.

[0128] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A system for constant temperature control of paste resin polymerization process, characterized in that: include: A data monitoring module, which is used to monitor in real time the temperature of several preset points in the polymerization kettle, the temperature of the outlet of the circulation pump, and the gas pressure in the polymerization kettle; A database, which is connected to the data monitoring module and is used to store the temperature and air pressure data monitored by the data monitoring module and the corresponding monitoring time points; A temperature prediction module, which is connected to the database and is used to determine whether the pressure change in the polymerization kettle meets the preset standard, and based on the result of the determination that the pressure changes in the polymerization kettle meet the preset standard, predict the temperature of the polymerization kettle at a future target time point according to the temperatures of several preset points in the polymerization kettle to obtain a predicted temperature; a data processing module, which is connected to the temperature prediction module and the database respectively, and is used to determine the temperature adjustment amount in the circulation pump according to the predicted temperature and the current temperature of the circulation pump outlet, and determine the valve adjustment method according to the temperature adjustment amount, including the adjustment method of the cold water valve, the hot water valve and the circulating water valve; A valve adjustment module, which is connected to the data processing module and is used to adjust the valve openings of the cold water valve, the hot water valve and the circulating water valve respectively according to the valve adjustment mode determined by the data processing module; A correction module is connected to the database and is used to correct the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time in the future.

2. The system for constant temperature control of paste resin polymerization process according to claim 1, characterized in that: The temperature prediction module comprises: An air pressure determination submodule, which is connected to the database and is used to determine whether the air pressure change in the polymerization kettle meets a preset standard; the preset standard is that the air pressure change in the polymerization kettle per unit time is greater than a preset change threshold; An early warning temperature determination submodule, which is connected to the air pressure determination submodule and the database, respectively, and is used to determine the early warning temperature according to the temperature of each preset point in the polymerization kettle when the air pressure determination submodule determines that the air pressure change in the polymerization kettle meets the preset standard; The predicted temperature determination submodule is connected to the early warning temperature determination submodule and is used to predict the temperature at a future target time point in the polymerization kettle according to the historical temperature of the preset point corresponding to the early warning temperature to obtain the predicted temperature.

3. The system for constant temperature control of paste resin polymerization process according to claim 2, characterized in that: The data processing module comprises: A heat exchange temperature determination submodule, which is connected to the temperature prediction module and is used to determine the heat exchange temperature according to the predicted temperature and the standard reaction temperature; a temperature adjustment amount determination submodule, which is connected to the heat exchange temperature determination submodule and the database respectively, and is used to determine the temperature adjustment amount in the circulation pump according to the heat exchange temperature and the current temperature of the circulation pump outlet; The valve adjustment mode determination submodule is connected to the temperature adjustment amount determination submodule, and is used to compare the temperature adjustment amount with a preset adjustment amount threshold, and determine the valve adjustment mode according to the comparison result, including the adjustment mode of the cold water valve, hot water valve and circulating water valve.

4. The system for constant temperature control of paste resin polymerization process according to claim 3, characterized in that: The correction module comprises: A temperature analysis submodule, which is connected to the database and is used to analyze the temperature changes of several preset points in the polymerization kettle within a preset time period in the future to determine the temperature change characteristic value of each preset point; A data comparison submodule, which is connected to the temperature analysis submodule, and is used to compare each of the temperature change characteristic values ​​with a preset temperature characteristic value, and determine a target temperature change characteristic value according to the comparison result; The correction submodule is connected to the data comparison submodule, and is used to determine the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point, and compare the target temperature with the predicted temperature, and correct the opening of each valve according to the comparison result.

5. The system for constant temperature control of paste resin polymerization process according to claim 4, characterized in that: The correction submodule comprises: A correction analysis unit connected to the data comparison submodule, for comparing the preset point corresponding to the target temperature change characteristic value with the preset point corresponding to the predicted temperature, and determining the target temperature according to the comparison result; The correction unit is connected to the correction analysis unit and is used to compare the target temperature with the predicted temperature and correct the opening of each valve according to the comparison result.

6. The system for constant temperature control of paste resin polymerization process according to claim 5, characterized in that: The correction analysis unit determines the target temperature according to the comparison result, including: The correction analysis unit determines the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point as the target temperature based on the comparison result that the preset point corresponding to the target temperature change characteristic value is consistent with the preset point corresponding to the predicted temperature; The correction analysis unit determines the target temperature according to the temperature of the preset point corresponding to the target temperature change characteristic value at the target time point and the preset temperature coefficient based on the comparison result that the preset point corresponding to the target temperature change characteristic value is inconsistent with the preset point corresponding to the predicted temperature.

7. The system for constant temperature control of paste resin polymerization process according to claim 6, characterized in that: The warning temperature determination submodule determines the temperature of the preset point corresponding to the maximum difference between the temperature of each preset point in the polymerization kettle and the preset temperature threshold as the warning temperature based on the result that the air pressure determination submodule determines that the air pressure change in the polymerization kettle meets the preset standard.

8. The system for constant temperature control of paste resin polymerization process according to claim 7, characterized in that: The valve adjustment mode determination submodule determines the valve adjustment mode as the first adjustment mode or the second adjustment mode based on the comparison result that the temperature adjustment amount is less than 0 and the comparison result of the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference; The valve adjustment mode determination submodule determines that the valve adjustment mode is the third adjustment mode or the fourth adjustment mode based on the comparison result that the temperature adjustment amount is greater than 0 and the comparison result of the difference between the absolute value of the temperature adjustment amount and the preset adjustment amount threshold and the second preset difference; Among them, the first adjustment method is to adjust the valve opening of the cold water valve and the circulating water valve, and keep the hot water valve closed; the second adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed; the third adjustment method is to adjust the valve opening of the hot water valve and the circulating water valve, and keep the cold water valve closed; the fourth adjustment method is to adjust the valve opening of the circulating water valve, and keep the cold water valve and the hot water valve closed.

9. The system for constant temperature control of paste resin polymerization process according to claim 8, characterized in that: The temperature analysis submodule determines the temperature change characteristic value of each preset point according to the ratio of the temperature difference of the next adjacent time point to the temperature difference of the previous adjacent time point of each preset point in the polymerization kettle within the future preset time period.

10. A constant temperature control method for a system for constant temperature control of a paste resin polymerization process according to any one of claims 1 to 9, characterized in that: include: Step S1, obtaining the temperatures of several preset points in the polymerization kettle, the temperature of the outlet of the circulation pump, and the gas pressure in the polymerization kettle; Step S2, predicting the temperature at a future target time point in the polymerization kettle according to the temperature and air pressure data of several preset points in the polymerization kettle to obtain a predicted temperature; Step S3, determining a temperature adjustment amount in the circulation pump according to the predicted temperature and the current temperature at the outlet of the circulation pump, and determining a valve adjustment method according to the temperature adjustment amount, including an adjustment method of a cold water valve, a hot water valve, and a circulating water valve; Step S4, adjusting the valve openings of the cold water valve, the hot water valve and the circulating water valve respectively according to the valve adjustment method; Step S5, correcting the opening of each valve according to the temperature change of several preset points in the polymerization kettle within a preset time period in the future.

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