Molding energy saving molding method and system based on waste heat recovery management

Abstract

The present application relates to the field of molding forming, and discloses a molding energy-saving forming method and system based on waste heat recovery management, comprising the following steps: collecting global waste heat correlation data of equipment, dividing independent heat units to construct a heat transfer matrix and a global heat loss digital atlas, and completing waste heat grade classification; then, realizing waste heat cascade shunting and graded closed energy storage regulation according to the atlas; realizing raw material waste heat drying self-adaptive temperature control relying on a fuzzy PID double closed loop algorithm, using high temperature waste heat to complete mold partition preheating, and carrying out dynamic heat balance compensation during the melting injection stage; finally, collecting the residual temperature of the opened mold workpiece, and completing low-grade waste heat bottom-up reuse. The present application realizes global waste heat intelligent management and control relying on a central data analysis unit, matches different grade waste heat for on-demand reuse, eliminates cold and hot energy consumption offset, and improves waste heat utilization rate and mold temperature uniformity.

Description

Technical Field

[0001] This invention relates to the field of molding, and in particular to an energy-saving molding method and system based on waste heat recovery management. Background Technology

[0002] In conventional mass production of plastic molding, equipment often experiences significant unorganized heat loss: radiant heat from the outer wall of the melting barrel, heat released from hot water during mold cooling, heat generated by the hydraulic system, residual heat from the molded parts after mold opening, and waste heat from exhaust from the mold temperature controller. Current methods mostly involve directly venting these various types of waste heat on-site, with only a few simple devices using a single water tank for mixed storage and reuse, without distinguishing between heat, temperature, and grade. Traditional molding processes rely on electric heating to complete the entire heat supply for particle drying, mold heating, and barrel melting and insulation. This results in a severe energy imbalance between hot and cold processes, with high-flow-rate cold water cooling of the mold and high-power electric heating of the barrel operating simultaneously, leading to consistently high overall electrical and thermal energy consumption. Furthermore, manual, fixed-level control of the heat exchange flow rate cannot match changes in mold opening and closing cycles, raw material grades, and ambient temperature, resulting in large fluctuations in heat exchange utilization and the potential for uneven mold temperature leading to quality defects such as shrinkage and warping of the plastic parts.

[0003] Existing waste heat recovery devices generally lack a comprehensive sensing and intelligent scheduling system, and there is no standardized heat loss calculation model. The mixed storage of high and low temperature waste heat causes degradation and loss of high-grade heat energy. The utilization scenarios of waste heat are limited and single, mostly only providing simple auxiliary raw material waste heat, which is difficult to cover multiple stages such as mold preheating, hydraulic insulation, and workshop heating. Moreover, the control logic is mostly a fixed value switch mode, without adaptive adjustment and fault compensation mechanisms. Once the heat exchanger scales or the sensor malfunctions, the waste heat supply drops sharply, and the auxiliary electric heating must be turned on immediately, resulting in poor energy-saving stability. The industry lacks an integrated management method for molding that runs through the entire molding process, allocates waste heat in stages according to grade, and combines intelligent algorithms to dynamically balance the molding heat demand and recovered heat.

[0004] This paper proposes a molding energy-saving method based on waste heat recovery management, which addresses the pain points of existing technologies such as high energy consumption, large waste heat, rigid control, and poor energy-saving sustainability from all dimensions, including heat source recovery, energy storage and allocation, intelligent temperature control, and iterative optimization. Summary of the Invention

[0005] This invention overcomes the shortcomings of the prior art and provides a molding energy-saving molding method and system based on waste heat recovery management.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first aspect of this invention provides a molding energy-saving method based on waste heat recovery management, comprising the following steps: Full-domain layered waste heat correlation data is collected for the molding equipment, and independent heat transfer units are divided to construct a heat transfer matrix. At the same time, a full-domain digital heat loss map is constructed based on the independent heat transfer units and the heat transfer matrix. Based on the digital map of heat loss across the entire area, the target equipment is subjected to waste heat cascade diversion and closed-loop energy storage regulation. Based on the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced to perform adaptive energy-saving reuse of raw material waste heat drying. Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop by zone, and dynamic thermal balance compensation is performed during the melting and injection stage of the target equipment's mold. After the melt injection stage of the target mold, the residual heat collection and low-grade residual heat utilization are carried out during mold opening and unloading.

[0007] Furthermore, in a preferred embodiment of the present invention, the step of collecting comprehensive layered waste heat correlation data of the molding equipment and dividing it into independent heat transfer units to construct a heat transfer matrix, and simultaneously constructing a comprehensive digital heat loss map based on the independent heat transfer units and the heat transfer matrix, specifically involves: Identify the molding equipment and calibrate it as the target equipment. Deploy waste heat correlation data sensors in all waste heat generation areas within the target equipment to collect waste heat correlation data of the target equipment. Deploy a central data analysis unit to connect different waste heat correlation data sensors. Among them, the data types of waste heat related data of the target equipment include real-time temperature of each waste heat generation area, flow rate of heat exchange medium, pipeline pressure, equipment servo load, mold opening and closing time, and melt injection cycle time. The physical structure and heat transfer path of the target equipment are determined and used as the boundary of the independent thermal unit. Based on the boundary of the independent thermal unit, the target equipment is disassembled into different independent thermal units, including the barrel heating unit, the mold gate heating unit, the mold thick-walled cavity heating unit, the mold thin-walled cavity heating unit, the hydraulic oil heat dissipation unit, the exhaust waste heat unit, and the workpiece surface heat dissipation unit. By introducing the basic heat transfer principles of heat conduction, heat radiation, and heat convection, and combining different independent heat units, a heat transfer matrix is ​​constructed and fitted and corrected. Each set of heat transfer characteristic parameters in the heat transfer matrix corresponds to a single independent heat unit, and the heat transfer characteristic parameters include the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time. The central data analysis unit calculates the heat loss of each heat unit by analyzing the heat transfer characteristic parameters, and divides the heat loss of each waste heat generation area in the form of a visual digital map, outputting a full-domain heat loss digital map. The raw material grade, molding process parameters and ambient temperature and humidity of the target equipment are synchronously bound in the full-domain heat loss digital map as dynamic boundary conditions of the map. Based on the global heat loss digital map, the waste heat grade of different independent heat units is classified to obtain high temperature waste heat range, medium temperature waste heat range and low temperature waste heat range, and the waste heat grade of different independent heat units is zoned and marked.

[0008] Furthermore, in a preferred embodiment of the present invention, the step of performing waste heat cascade diversion and closed-loop energy storage regulation on the target equipment based on the global heat loss digital spectrum specifically includes: In the target equipment, based on the waste heat grade classification results, waste heat diversion pipelines are configured in different independent thermal units and connected to the central data analysis unit. The central data analysis unit outputs waste heat grade classification scheduling signals to control the waste heat diversion pipelines to perform waste heat diversion operations. Acquire heat transfer oil storage tanks, greywater storage tanks, and low-temperature energy storage water tanks, and connect them to different independent thermal units of the target equipment; The connection method is as follows: the independent heat unit marked as the high temperature waste heat zone is connected to the heat transfer oil energy storage tank; the independent heat unit marked as the medium temperature waste heat zone is connected to the greywater energy storage tank; and the independent heat unit marked as the low temperature waste heat zone is connected to the low temperature energy storage water tank. Among them, the waste heat diversion operation is to introduce high-temperature waste heat into the heat transfer oil storage tank, medium-temperature waste heat into the greywater storage tank, and low-temperature waste heat into the low-temperature energy storage water tank. The central data analysis unit collects temperature and pressure data of the heat transfer oil storage tank, the greywater storage tank and the low temperature energy storage tank in real time. This data is used to calculate the waste heat storage capacity inside the storage tank and to compare and analyze the heat demand threshold of the target equipment forming process. If the residual heat storage capacity inside the energy storage tank is greater than the heat demand threshold of the molding process of the target equipment, the excess will be converted into electrical energy and fed back to the target equipment. If the residual heat storage capacity inside the energy storage tank is less than the heat demand threshold of the molding process of the target equipment, the heat loss of each independent heat unit will be continuously collected for sealed heat storage.

[0009] Furthermore, in a preferred embodiment of the present invention, the introduction of a fuzzy PID dual-closed-loop algorithm based on the central data analysis unit for implementing adaptive energy-saving reuse of raw material waste heat drying specifically involves: Obtain the molding material for the target equipment and designate it as the target material; Through the central data analysis unit, the waste heat storage capacity inside the greywater energy storage tank is retrieved, and combined with the raw material grade, molding process parameters and dynamic boundary conditions of ambient temperature and humidity bound by the full-domain heat loss digital map, the waste heat process reference temperature of the target raw material is matched and generated. By introducing a plate heat exchanger, the waste heat stored inside the greywater storage tank is converted into constant temperature hot air, which is then transported to the hopper drying chamber in the target equipment for waste heat drying of the target raw materials. In the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced. During the waste heat drying process of the target raw material, the hot air outlet temperature of the hopper drying chamber, the real-time moisture content of the raw material, and the ambient humidity are used as the outer loop acquisition parameters, and the water outlet temperature of the greywater storage tank and the heat exchange temperature difference are used as the inner loop acquisition parameters. By using the control logic of the fuzzy PID dual closed-loop algorithm, and combining the outer loop and inner loop acquisition parameters, the internal parameters of the plate heat exchanger are corrected and controlled in real time. This adaptively matches the waste heat demand of the target raw material, and completes the adaptive energy-saving reuse treatment of raw material waste heat drying.

[0010] Furthermore, in a preferred embodiment of the present invention, the residual heat storage capacity inside the heat transfer oil storage tank is used to perform zoned residual heat closed-loop control on the molding die of the target equipment, and dynamic thermal balance compensation is performed during the melt injection stage of the molding die of the target equipment, specifically as follows: The molding mold of the target equipment is calibrated as the target mold, and three temperature control zones are obtained: the mold gate thermal unit, the mold thick-walled cavity thermal unit, and the mold thin-walled cavity thermal unit. Each temperature control zone is equipped with temperature sensors and flow control valves, and is connected to the central data analysis unit. Based on the target mold, the molding process is carried out. Before the molding process, the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time are determined for different temperature control zones. The heat transfer oil delivery flow rate and the duration of the residual heat are matched in real time through the central data analysis unit, combined with the residual heat storage capacity of the heat transfer oil storage tank. The central data analysis unit receives real-time temperature feedback from temperature sensors in different temperature control zones and compares the difference with the preset mold temperature in the molding process parameters bound in the digital graph of heat loss in the whole domain. If the difference exceeds the preset range, the opening of the flow regulating valve will be controlled in real time through the central data analysis unit until the difference does not exceed the preset range. Simultaneously, dynamic thermal balance compensation is performed during the melt injection stage of the target mold.

[0011] Furthermore, in a preferred embodiment of the present invention, the dynamic thermal balance compensation process performed during the melt injection stage of the target mold specifically includes: During the melt injection stage of the molding process, the central data analysis unit retrieves the melt injection cycle duration and the real-time temperature of the three temperature control zones of the target mold. Combined with the molding process parameters and the real-time heat loss data of each independent heat unit in the global heat loss digital spectrum, the instantaneous heat generation of the barrel heating unit and the real-time heat dissipation of each temperature control zone of the target mold are calculated. Meanwhile, during the melt injection stage of the molding process, the power of the barrel heating unit is regulated by the central data analysis unit to maintain the output of the barrel heating unit to the melt heat preservation power required for the molding process, and the waste heat medium output by the water storage tank is controlled to cool the target mold at a constant temperature. During the constant temperature cooling process, the real-time temperature of the three temperature control zones of the target mold is monitored in real time through the central data analysis unit. If the temperature exceeds the preset value, the flow rate of the waste heat medium output from the water storage tank is adjusted to complete the dynamic thermal balance compensation process of the target mold during the melting injection stage.

[0012] Furthermore, in a preferred embodiment of the present invention, the step of collecting residual heat and utilizing low-grade residual heat after the mold opening and unloading process following the melt injection stage of the target mold specifically involves: After the melting and injection stage of the target mold, the pressure holding and shaping of the target equipment is performed, and the target mold is opened for unloading. During the unloading process, the central data analysis unit collects the surface residual temperature data of the demolded molded workpiece and obtains the heat loss of the heat dissipation unit on the workpiece surface, which is used to calculate the low-temperature residual heat of the heat dissipation unit on the workpiece surface. The low-temperature waste heat from the heat dissipation unit on the workpiece surface is transferred to a low-temperature energy storage tank for low-grade waste heat recovery.

[0013] A second aspect of the present invention also provides a molding energy-saving molding system based on waste heat recovery management. The molding energy-saving molding system integrates a high-performance computing architecture and a data storage module, including a non-volatile memory consisting of a DDR4 RDIMM memory module with ECC verification and an NVMe solid-state storage array using 3D NAND flash memory, and a multi-core processor based on the Zen4 microarchitecture. The memory contains a molding energy-saving molding method program with a molding energy-saving molding engine. When the program is executed in parallel through a superscalar pipeline execution unit within the processor, the following steps are implemented: Full-domain layered waste heat correlation data is collected for the molding equipment, and independent heat transfer units are divided to construct a heat transfer matrix. At the same time, a full-domain digital heat loss map is constructed based on the independent heat transfer units and the heat transfer matrix. Based on the digital map of heat loss across the entire area, the target equipment is subjected to waste heat cascade diversion and closed-loop energy storage regulation. Based on the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced to perform adaptive energy-saving reuse of raw material waste heat drying. Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop by zone, and dynamic thermal balance compensation is performed during the melting and injection stage of the target equipment's mold. After the melt injection stage of the target mold, the residual heat collection and low-grade residual heat utilization are carried out during mold opening and unloading.

[0014] This invention addresses the technical deficiencies in the prior art and offers the following advantages: It collects waste heat data across the entire equipment area, divides the data into independent heat units to construct a heat transfer matrix and a digital spectrum of heat loss across the entire area, and completes the classification of waste heat grades. Based on the spectrum, it achieves tiered diversion and graded closed-loop energy storage control of waste heat. It utilizes a fuzzy PID dual-loop algorithm to achieve adaptive temperature control for raw material waste heat drying, uses high-temperature waste heat to preheat mold zones, and performs dynamic thermal balance compensation during the melt injection stage. Finally, it collects the residual temperature of the molded workpiece, completing the reuse of low-grade waste heat. This invention relies on a central data analysis unit to achieve intelligent management and control of waste heat throughout the entire process, matching different grades of waste heat for on-demand reuse, eliminating the offsetting of hot and cold energy consumption, and improving waste heat utilization and mold temperature uniformity. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0016] Figure 1 A flowchart of a molding energy-saving molding method based on waste heat recovery management is shown; Figure 2 A flowchart of the method for zoned waste heat closed-loop control and dynamic thermal balance compensation of the target equipment mold is shown. Figure 3 A program view of a molding energy-saving molding system based on waste heat recovery management is shown. Detailed Implementation

[0017] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0018] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0019] Figure 1 A flowchart of a molding energy-saving method based on waste heat recovery management is shown, including the following steps: S102: Collect all-domain layered waste heat correlation data for the molding equipment, divide it into independent heat transfer units to construct a heat transfer matrix, and construct a digital map of all-domain heat loss based on the independent heat transfer units and the heat transfer matrix. S104: Based on the digital map of heat loss across the entire region, perform waste heat cascade diversion and closed-loop energy storage regulation on the target equipment; S106: Based on the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced to perform adaptive energy-saving reuse of raw material waste heat drying; S108: Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop within a zone, and dynamic thermal balance compensation is performed during the melt injection stage of the target equipment's mold. S110: After the melt injection stage of the target mold, perform mold opening and unloading residual heat collection and low-grade residual heat utilization treatment.

[0020] Furthermore, in a preferred embodiment of the present invention, the step of collecting comprehensive layered waste heat correlation data of the molding equipment and dividing it into independent heat transfer units to construct a heat transfer matrix, and simultaneously constructing a comprehensive digital heat loss map based on the independent heat transfer units and the heat transfer matrix, specifically involves: Identify the molding equipment and calibrate it as the target equipment. Deploy waste heat correlation data sensors in all waste heat generation areas within the target equipment to collect waste heat correlation data of the target equipment. Deploy a central data analysis unit to connect different waste heat correlation data sensors. Among them, the data types of waste heat related data of the target equipment include real-time temperature of each waste heat generation area, flow rate of heat exchange medium, pipeline pressure, equipment servo load, mold opening and closing time, and melt injection cycle time. The physical structure and heat transfer path of the target equipment are determined and used as the boundary of the independent thermal unit. Based on the boundary of the independent thermal unit, the target equipment is disassembled into different independent thermal units, including the barrel heating unit, the mold gate heating unit, the mold thick-walled cavity heating unit, the mold thin-walled cavity heating unit, the hydraulic oil heat dissipation unit, the exhaust waste heat unit, and the workpiece surface heat dissipation unit. By introducing the basic heat transfer principles of heat conduction, heat radiation, and heat convection, and combining different independent heat units, a heat transfer matrix is ​​constructed and fitted and corrected. Each set of heat transfer characteristic parameters in the heat transfer matrix corresponds to a single independent heat unit, and the heat transfer characteristic parameters include the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time. The central data analysis unit calculates the heat loss of each heat unit by analyzing the heat transfer characteristic parameters, and divides the heat loss of each waste heat generation area in the form of a visual digital map, outputting a full-domain heat loss digital map. The raw material grade, molding process parameters and ambient temperature and humidity of the target equipment are synchronously bound in the full-domain heat loss digital map as dynamic boundary conditions of the map. Based on the global heat loss digital map, the waste heat grade of different independent heat units is classified to obtain high temperature waste heat range, medium temperature waste heat range and low temperature waste heat range, and the waste heat grade of different independent heat units is zoned and marked.

[0021] It's important to note that the first step is to comprehensively sense the waste heat of the equipment, simultaneously linking molding process timing data and thermal data to achieve co-source acquisition of process and waste heat data. The complex overall heat transfer system is then broken down into multiple independent and controllable units, enabling zoned heat calculation and avoiding errors caused by overall heat measurement. The advantage is precise heat loss location, accurately pinpointing high-loss heat sources within the equipment, facilitating targeted waste heat recovery. Combining the three fundamental heat transfer principles of heat conduction, radiation, and convection, each independent thermal unit is matched with unique heat transfer characteristic parameters, constructing a dedicated heat transfer matrix. Matrix fitting and correction are then performed to quantify the heat dissipation, heat transfer coefficient, and heat loss rate of each thermal unit. A central data analysis unit calculates the heat loss of each unit, outputting a visualized, full-domain heat loss digital map, simultaneously binding raw material grade, molding process parameters, and ambient temperature and humidity as dynamic boundary conditions. The aim is to intuitively display the heat loss distribution in different areas of the equipment, while adapting to changes in operating conditions such as material changes, process adjustments, and seasonal temperature and humidity variations, ensuring real-time synchronous updates of heat data. Finally, based on the digital map of heat loss across the entire area, the waste heat is divided into three levels: high, medium, and low, and the waste heat grade is marked for each independent heat unit.

[0022] The method for classifying waste heat into high, medium, and low grades involves pre-setting three temperature thresholds: 120℃, 50℃, and 30℃. Based on real-time temperature data of each thermal unit within the heat loss digital spectrum, waste heat is graded and labeled. Waste heat in the 120℃–260℃ range is classified as high-temperature waste heat, 50℃–120℃ as medium-temperature waste heat, and 30℃–50℃ as low-temperature waste heat. The heat transfer matrix fitting algorithm operates as follows: Multiple batches of synchronously collected temperature, flow, and pressure time-series sensor data are used as input samples. These are substituted into a set of heat transfer equations (heat conduction, heat radiation, and heat convection) for iterative calculation. The difference between the theoretical heat dissipation of each independent thermal unit and the measured heat dissipation is continuously compared. The heat transfer coefficient and the heat loss rate per unit time are automatically corrected until the difference between the theoretical and measured heat values ​​converges to a preset allowable error range.

[0023] Furthermore, in a preferred embodiment of the present invention, the step of performing waste heat cascade diversion and closed-loop energy storage regulation on the target equipment based on the global heat loss digital spectrum specifically includes: In the target equipment, based on the waste heat grade classification results, waste heat diversion pipelines are configured in different independent thermal units and connected to the central data analysis unit. The central data analysis unit outputs waste heat grade classification scheduling signals to control the waste heat diversion pipelines to perform waste heat diversion operations. Acquire heat transfer oil storage tanks, greywater storage tanks, and low-temperature energy storage water tanks, and connect them to different independent thermal units of the target equipment; The connection method is as follows: the independent heat unit marked as the high temperature waste heat zone is connected to the heat transfer oil energy storage tank; the independent heat unit marked as the medium temperature waste heat zone is connected to the greywater energy storage tank; and the independent heat unit marked as the low temperature waste heat zone is connected to the low temperature energy storage water tank. Among them, the waste heat diversion operation is to introduce high-temperature waste heat into the heat transfer oil storage tank, medium-temperature waste heat into the greywater storage tank, and low-temperature waste heat into the low-temperature energy storage water tank. The central data analysis unit collects temperature and pressure data of the heat transfer oil storage tank, the greywater storage tank and the low temperature energy storage tank in real time. This data is used to calculate the waste heat storage capacity inside the storage tank and to compare and analyze the heat demand threshold of the target equipment forming process. If the residual heat storage capacity inside the energy storage tank is greater than the heat demand threshold of the molding process of the target equipment, the excess will be converted into electrical energy and fed back to the target equipment. If the residual heat storage capacity inside the energy storage tank is less than the heat demand threshold of the molding process of the target equipment, the heat loss of each independent heat unit will be continuously collected for sealed heat storage.

[0024] It should be noted that, firstly, waste heat diversion pipelines are laid out, and all pipelines are connected to the central data analysis unit. The central data analysis unit issues dispatch signals to automatically control the pipelines to complete the waste heat diversion, realizing intelligent centralized control of the waste heat transfer process. Additionally, three types of independent, sealed energy storage devices are configured: a heat transfer oil storage tank, a greywater storage tank, and a low-temperature energy storage tank, each corresponding to different temperature ranges of waste heat, maximizing the usability of the retained waste heat. Specifically, the waste heat medium corresponding to the high-temperature waste heat in the range of 120℃ to 260℃, namely the barrel heating unit and the exhaust waste heat unit, is introduced into the first-stage vacuum insulated sealed heat transfer oil energy storage tank. The cooling waste heat medium corresponding to the medium-temperature waste heat in the range of 50℃ to 120℃, namely the mold gate heat unit, the mold thick-wall cavity heat unit, and the mold thin-wall cavity heat unit, is introduced into the second-stage medium-water sealed energy storage tank. The low-temperature waste heat corresponding to the low-temperature waste heat in the range of 30℃ to 50℃, namely the hydraulic oil heat dissipation unit and the workpiece surface heat dissipation unit, is collected and transported to the low-temperature sealed energy storage water tank on the side of the heat pump evaporator. The three types of energy storage tanks are independently isolated from each other to prevent the mixing of waste heat media of different grades from causing heat energy degradation and loss.

[0025] The system collects temperature and pressure parameters from each energy storage tank in real time, accurately calculates the real-time waste heat storage capacity within the tanks, and compares this data with the preset heat demand thresholds for subsequent molding processes. This allows for real-time monitoring of the energy storage system's heat surplus / deficit status, providing data for subsequent heat allocation and waste heat reuse, thus achieving closed-loop monitoring of energy storage. Finally, if the waste heat storage capacity exceeds the process heat demand threshold, the excess heat is converted into electrical energy feedback equipment; if the waste heat storage capacity is insufficient, the external discharge branch is shut down, and heat loss from each independent heat unit is continuously collected for heat storage.

[0026] Furthermore, in a preferred embodiment of the present invention, the introduction of a fuzzy PID dual-closed-loop algorithm based on the central data analysis unit for implementing adaptive energy-saving reuse of raw material waste heat drying specifically involves: Obtain the molding material for the target equipment and designate it as the target material; Through the central data analysis unit, the waste heat storage capacity inside the greywater energy storage tank is retrieved, and combined with the raw material grade, molding process parameters and dynamic boundary conditions of ambient temperature and humidity bound by the full-domain heat loss digital map, the waste heat process reference temperature of the target raw material is matched and generated. By introducing a plate heat exchanger, the waste heat stored inside the greywater storage tank is converted into constant temperature hot air, which is then transported to the hopper drying chamber in the target equipment for waste heat drying of the target raw materials. In the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced. During the waste heat drying process of the target raw material, the hot air outlet temperature of the hopper drying chamber, the real-time moisture content of the raw material, and the ambient humidity are used as the outer loop acquisition parameters, and the water outlet temperature of the greywater storage tank and the heat exchange temperature difference are used as the inner loop acquisition parameters. By using the control logic of the fuzzy PID dual closed-loop algorithm, and combining the outer loop and inner loop acquisition parameters, the internal parameters of the plate heat exchanger are corrected and controlled in real time. This adaptively matches the waste heat demand of the target raw material, and completes the adaptive energy-saving reuse treatment of raw material waste heat drying.

[0027] It should be noted that, firstly, the target raw material is determined, and the real-time waste heat storage capacity of the greywater storage tank is retrieved through the central data analysis unit. Combined with the raw material grade, molding process parameters, and dynamic boundary conditions of ambient temperature and humidity linked to the digital map of the entire heat loss domain, a waste heat process reference temperature suitable for the target raw material is automatically generated. In other words, the required drying temperature is automatically matched, avoiding the setting temperature from deviating from the actual heat storage capacity or raw material process requirements. Subsequently, the waste heat of the greywater stored in the storage tank is converted into a heat energy form, transforming the liquid waste heat into a hot air heat source required for raw material drying, realizing the direct reuse of medium-temperature waste heat and replacing the traditional electric heating drying module.

[0028] A fuzzy PID dual-loop algorithm is introduced. The outer loop collects the hot air outlet temperature of the hopper, the moisture content of the raw material, and the ambient humidity; the inner loop collects the water outlet temperature of the water storage tank and the heat exchange temperature difference, forming a dual-layer monitoring parameter system. The outer loop monitors the actual drying effect of the raw material, while the inner loop monitors the stability of the waste heat source supply, simultaneously considering both the quality of the dried product and fluctuations in the waste heat source, achieving bidirectional monitoring. Unlike traditional single-loop PID control methods that only monitor the hot air temperature, this approach adds monitoring dimensions for raw material moisture content and heat exchange temperature difference, taking into account both drying quality and heat source stability. Subsequently, the heat exchange flow rate and hot air temperature are automatically adjusted based on heat source fluctuations, environmental changes, and changes in the moisture content of the raw material, ensuring a constant temperature throughout the drying process.

[0029] Furthermore, in a preferred embodiment of the present invention, the step of collecting residual heat and utilizing low-grade residual heat after the mold opening and unloading process following the melt injection stage of the target mold specifically involves: After the melting and injection stage of the target mold, the pressure holding and shaping of the target equipment is performed, and the target mold is opened for unloading. During the unloading process, the central data analysis unit collects the surface residual temperature data of the demolded molded workpiece and obtains the heat loss of the heat dissipation unit on the workpiece surface, which is used to calculate the low-temperature residual heat of the heat dissipation unit on the workpiece surface. The low-temperature waste heat from the heat dissipation unit on the workpiece surface is transferred to a low-temperature energy storage tank for low-grade waste heat recovery.

[0030] It should be noted that after the melt injection stage, the plastic part is first held under pressure and shaped before the target mold is opened to complete the unloading operation. During the unloading process, the central data analysis unit collects the residual temperature data of the demolded workpiece surface in real time, and simultaneously obtains the heat loss parameters corresponding to the heat dissipation unit on the workpiece surface, accurately calculating the total amount of low-temperature waste heat generated by the unit. The purpose is to achieve comprehensive monitoring of all heat sources of the entire machine. Finally, the calculated and collected low-temperature waste heat from the workpiece surface is uniformly transported to the pre-installed low-temperature energy storage tank for storage, completing the bottom-line recovery and subsequent reuse preparation of low-grade waste heat throughout the entire process. The advantage is that it can further improve the overall waste heat recovery rate of the entire machine, make full use of low-grade waste heat, and, in conjunction with the pre-installed graded energy storage system, achieve full resource utilization of high, medium, and low-grade waste heat, maximizing the overall energy-saving effect.

[0031] Figure 2 A flowchart illustrating the method for zoned waste heat closed-loop control and dynamic thermal balance compensation of the target equipment mold is shown, including the following steps: S202: Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop by zone, and dynamic heat balance compensation is performed during the melt injection stage of the target equipment's mold. S204: Dynamic thermal balance compensation is performed during the melt injection stage of the target mold.

[0032] Furthermore, in a preferred embodiment of the present invention, the residual heat storage capacity inside the heat transfer oil storage tank is used to perform zoned residual heat closed-loop control on the molding die of the target equipment, and dynamic thermal balance compensation is performed during the melt injection stage of the molding die of the target equipment, specifically as follows: The molding mold of the target equipment is calibrated as the target mold, and three temperature control zones are obtained: the mold gate thermal unit, the mold thick-walled cavity thermal unit, and the mold thin-walled cavity thermal unit. Each temperature control zone is equipped with temperature sensors and flow control valves, and is connected to the central data analysis unit. Based on the target mold, the molding process is carried out. Before the molding process, the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time are determined for different temperature control zones. The heat transfer oil delivery flow rate and the duration of the residual heat are matched in real time through the central data analysis unit, combined with the residual heat storage capacity of the heat transfer oil storage tank. The central data analysis unit receives real-time temperature feedback from temperature sensors in different temperature control zones and compares the difference with the preset mold temperature in the molding process parameters bound in the digital graph of heat loss in the whole domain. If the difference exceeds the preset range, the opening of the flow regulating valve will be controlled in real time through the central data analysis unit until the difference does not exceed the preset range. Simultaneously, dynamic thermal balance compensation is performed during the melt injection stage of the target mold.

[0033] It should be noted that the mold is divided into three temperature control zones: the mold gate heat unit, the mold thick-walled cavity heat unit, and the mold thin-walled cavity heat unit. Heat supply is matched specifically to these zones to prevent localized overheating or underheating. Temperature sensors and flow control valves are installed in each temperature control zone, and all components are connected to a central data analysis unit. The central data analysis unit retrieves three types of heat transfer characteristic parameters for each temperature control zone: basic heat dissipation, heat transfer coefficient between the unit and the external environment, and heat loss rate per unit time. These parameters are combined with the real-time waste heat storage in the heat transfer oil storage tank. The central data analysis unit automatically matches the heat transfer oil flow rate and waste heat supply duration for each zone and then compares the temperature difference to determine whether the actual temperature in each zone of the mold meets the standard in real time, forming a temperature feedback closed loop and promptly identifying temperature deviations. When the difference between the measured temperature and the preset mold temperature exceeds the allowable range, the central data analysis unit automatically adjusts the opening of the corresponding zone's flow control valve until the temperature difference returns to the acceptable range.

[0034] Furthermore, in a preferred embodiment of the present invention, the dynamic thermal balance compensation process performed during the melt injection stage of the target mold specifically includes: During the melt injection stage of the molding process, the central data analysis unit retrieves the melt injection cycle duration and the real-time temperature of the three temperature control zones of the target mold. Combined with the molding process parameters and the real-time heat loss data of each independent heat unit in the global heat loss digital spectrum, the instantaneous heat generation of the barrel heating unit and the real-time heat dissipation of each temperature control zone of the target mold are calculated. Meanwhile, during the melt injection stage of the molding process, the power of the barrel heating unit is regulated by the central data analysis unit to maintain the output of the barrel heating unit to the melt heat preservation power required for the molding process, and the waste heat medium output by the water storage tank is controlled to cool the target mold at a constant temperature. During the constant temperature cooling process, the real-time temperature of the three temperature control zones of the target mold is monitored in real time through the central data analysis unit. If the temperature exceeds the preset value, the flow rate of the waste heat medium output from the water storage tank is adjusted to complete the dynamic thermal balance compensation process of the target mold during the melting injection stage.

[0035] It should be noted that during the melt injection stage, the molten raw material is introduced into the mold for molding. Accurate calculation of the instantaneous heat generation of the barrel heating unit and the real-time heat dissipation of each temperature-controlled zone in the mold is crucial for providing precise data for subsequent thermal balance control and avoiding blind temperature adjustments. The central data analysis unit reduces the operating power of the barrel heating unit, retaining only the basic insulation power required for the melt and eliminating redundant heating power. Simultaneously, a medium-temperature waste heat medium stored in a greywater storage tank replaces traditional ambient temperature cold water for constant-temperature cooling of the target mold. This significantly reduces the power consumption of continuous barrel heating while avoiding stress changes in the mold caused by drastic temperature differences with cold water, resulting in energy savings and extended mold lifespan. Finally, the real-time temperature of the three temperature-controlled zones in the mold is continuously monitored. When the zone temperature exceeds the preset process temperature threshold, the central data analysis unit automatically adjusts the flow rate of the waste heat medium output from the greywater storage tank, altering the mold's cooling heat exchange efficiency and ultimately achieving dynamic thermal balance compensation during the injection stage.

[0036] like Figure 3 As shown, the second aspect of the present invention also provides a molding energy-saving molding system based on waste heat recovery management. The molding energy-saving molding system integrates a high-performance computing architecture and a data storage module, including a non-volatile memory composed of a DDR4 RDIMM memory module with ECC verification and an NVMe solid-state storage array using 3D NAND flash memory, and a multi-core processor based on the Zen4 microarchitecture. The memory contains a molding energy-saving molding method program with a molding energy-saving molding engine. When the program is executed in parallel through a superscalar pipeline execution unit within the processor, the following steps are implemented: Full-domain layered waste heat correlation data is collected for the molding equipment, and independent heat transfer units are divided to construct a heat transfer matrix. At the same time, a full-domain digital heat loss map is constructed based on the independent heat transfer units and the heat transfer matrix. Based on the digital map of heat loss across the entire area, the target equipment is subjected to waste heat cascade diversion and closed-loop energy storage regulation. Based on the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced to perform adaptive energy-saving reuse of raw material waste heat drying. Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop by zone, and dynamic thermal balance compensation is performed during the melting and injection stage of the target equipment's mold. After the melt injection stage of the target mold, the residual heat collection and low-grade residual heat utilization are carried out during mold opening and unloading.

[0037] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A molding energy-saving method based on waste heat recovery management, characterized in that, Includes the following steps: Full-domain layered waste heat correlation data is collected for the molding equipment, and independent heat transfer units are divided to construct a heat transfer matrix. At the same time, a full-domain digital heat loss map is constructed based on the independent heat transfer units and the heat transfer matrix. Based on the digital map of heat loss across the entire area, the target equipment is subjected to waste heat cascade diversion and closed-loop energy storage regulation. Based on the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced to perform adaptive energy-saving reuse of raw material waste heat drying. Based on the residual heat storage capacity inside the heat transfer oil storage tank, the residual heat of the target equipment's mold is controlled in a closed loop by zone, and dynamic thermal balance compensation is performed during the melting and injection stage of the target equipment's mold. After the melt injection stage of the target mold, the residual heat collection and low-grade residual heat utilization are carried out during mold opening and unloading.

2. The energy-saving molding method based on waste heat recovery management according to claim 1, characterized in that, The process involves collecting comprehensive, layered waste heat correlation data from the molding equipment and dividing it into independent heat transfer units to construct a heat transfer matrix. Simultaneously, a comprehensive digital heat loss map is constructed based on the independent heat transfer units and the heat transfer matrix. Specifically: Identify the molding equipment and calibrate it as the target equipment. Deploy waste heat correlation data sensors in all waste heat generation areas within the target equipment to collect waste heat correlation data of the target equipment. Deploy a central data analysis unit to connect different waste heat correlation data sensors. Among them, the data types of waste heat related data of the target equipment include real-time temperature of each waste heat generation area, flow rate of heat exchange medium, pipeline pressure, equipment servo load, mold opening and closing time, and melt injection cycle time. The physical structure and heat transfer path of the target equipment are determined and used as the boundary of the independent thermal unit. Based on the boundary of the independent thermal unit, the target equipment is disassembled into different independent thermal units, including the barrel heating unit, the mold gate heating unit, the mold thick-walled cavity heating unit, the mold thin-walled cavity heating unit, the hydraulic oil heat dissipation unit, the exhaust waste heat unit, and the workpiece surface heat dissipation unit. By introducing the basic heat transfer principles of heat conduction, heat radiation, and heat convection, and combining different independent heat units, a heat transfer matrix is ​​constructed and fitted and corrected. Each set of heat transfer characteristic parameters in the heat transfer matrix corresponds to a single independent heat unit, and the heat transfer characteristic parameters include the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time. The central data analysis unit calculates the heat loss of each heat unit by analyzing the heat transfer characteristic parameters, and divides the heat loss of each waste heat generation area in the form of a visual digital map, outputting a full-domain heat loss digital map. The raw material grade, molding process parameters and ambient temperature and humidity of the target equipment are synchronously bound in the full-domain heat loss digital map as dynamic boundary conditions of the map. Based on the global heat loss digital map, the waste heat grade of different independent heat units is classified to obtain high temperature waste heat range, medium temperature waste heat range and low temperature waste heat range, and the waste heat grade of different independent heat units is zoned and marked.

3. The energy-saving molding method based on waste heat recovery management according to claim 1, characterized in that, Based on the global heat loss digital map, the target equipment is subjected to waste heat cascade diversion and closed-loop energy storage regulation treatment, specifically as follows: In the target equipment, based on the waste heat grade classification results, waste heat diversion pipelines are configured in different independent thermal units and connected to the central data analysis unit. The central data analysis unit outputs waste heat grade classification scheduling signals to control the waste heat diversion pipelines to perform waste heat diversion operations. Acquire heat transfer oil storage tanks, greywater storage tanks, and low-temperature energy storage water tanks, and connect them to different independent thermal units of the target equipment; The connection method is as follows: the independent heat unit marked as the high temperature waste heat zone is connected to the heat transfer oil energy storage tank; the independent heat unit marked as the medium temperature waste heat zone is connected to the greywater energy storage tank; and the independent heat unit marked as the low temperature waste heat zone is connected to the low temperature energy storage water tank. Among them, the waste heat diversion operation is to introduce high-temperature waste heat into the heat transfer oil storage tank, medium-temperature waste heat into the greywater storage tank, and low-temperature waste heat into the low-temperature energy storage water tank. The central data analysis unit collects temperature and pressure data of the heat transfer oil storage tank, the greywater storage tank and the low temperature energy storage tank in real time. This data is used to calculate the waste heat storage capacity inside the storage tank and to compare and analyze the heat demand threshold of the target equipment forming process. If the residual heat storage capacity inside the energy storage tank is greater than the heat demand threshold of the molding process of the target equipment, the excess will be converted into electrical energy and fed back to the target equipment. If the residual heat storage capacity inside the energy storage tank is less than the heat demand threshold of the molding process of the target equipment, the heat loss of each independent heat unit will be continuously collected for sealed heat storage.

4. The energy-saving molding method based on waste heat recovery management according to claim 1, characterized in that, The central data analysis unit introduces a fuzzy PID dual-closed-loop algorithm to perform adaptive energy-saving reuse of raw material waste heat drying, specifically as follows: Obtain the molding material for the target equipment and designate it as the target material; Through the central data analysis unit, the waste heat storage capacity inside the greywater energy storage tank is retrieved, and combined with the raw material grade, molding process parameters and dynamic boundary conditions of ambient temperature and humidity bound by the full-domain heat loss digital map, the waste heat process reference temperature of the target raw material is matched and generated. By introducing a plate heat exchanger, the waste heat stored inside the greywater storage tank is converted into constant temperature hot air, which is then transported to the hopper drying chamber in the target equipment for waste heat drying of the target raw materials. In the central data analysis unit, a fuzzy PID dual closed-loop algorithm is introduced. During the waste heat drying process of the target raw material, the hot air outlet temperature of the hopper drying chamber, the real-time moisture content of the raw material, and the ambient humidity are used as the outer loop acquisition parameters, and the water outlet temperature of the greywater storage tank and the heat exchange temperature difference are used as the inner loop acquisition parameters. By using the control logic of the fuzzy PID dual closed-loop algorithm, and combining the outer loop and inner loop acquisition parameters, the internal parameters of the plate heat exchanger are corrected and controlled in real time. This adaptively matches the waste heat demand of the target raw material, and completes the adaptive energy-saving reuse treatment of raw material waste heat drying.

5. The energy-saving molding method based on waste heat recovery management according to claim 1, characterized in that, The residual heat storage capacity inside the heat transfer oil storage tank is used to perform zoned residual heat closed-loop control on the molding die of the target equipment, and dynamic thermal balance compensation is performed during the melt injection stage of the molding die of the target equipment. Specifically: The molding mold of the target equipment is calibrated as the target mold, and three temperature control zones are obtained: the mold gate thermal unit, the mold thick-walled cavity thermal unit, and the mold thin-walled cavity thermal unit. Each temperature control zone is equipped with temperature sensors and flow control valves, and is connected to the central data analysis unit. Based on the target mold, the molding process is carried out. Before the molding process, the basic heat dissipation of the unit, the heat transfer coefficient between the unit and the outside world, and the heat loss rate of the unit per unit time are determined for different temperature control zones. The heat transfer oil delivery flow rate and the duration of the residual heat are matched in real time through the central data analysis unit, combined with the residual heat storage capacity of the heat transfer oil storage tank. The central data analysis unit receives real-time temperature feedback from temperature sensors in different temperature control zones and compares the difference with the preset mold temperature in the molding process parameters bound in the digital graph of heat loss in the whole domain. If the difference exceeds the preset range, the opening of the flow regulating valve will be controlled in real time through the central data analysis unit until the difference does not exceed the preset range. Simultaneously, dynamic thermal balance compensation is performed during the melt injection stage of the target mold.

6. The energy-saving molding method based on waste heat recovery management according to claim 5, characterized in that, The dynamic thermal balance compensation process during the melt injection stage of the target mold specifically includes: During the melt injection stage of the molding process, the central data analysis unit retrieves the melt injection cycle duration and the real-time temperature of the three temperature control zones of the target mold. Combined with the molding process parameters and the real-time heat loss data of each independent heat unit in the global heat loss digital spectrum, the instantaneous heat generation of the barrel heating unit and the real-time heat dissipation of each temperature control zone of the target mold are calculated. Meanwhile, during the melt injection stage of the molding process, the power of the barrel heating unit is regulated by the central data analysis unit to maintain the output of the barrel heating unit to the melt heat preservation power required for the molding process, and the waste heat medium output by the water storage tank is controlled to cool the target mold at a constant temperature. During the constant temperature cooling process, the real-time temperature of the three temperature control zones of the target mold is monitored in real time through the central data analysis unit. If the temperature exceeds the preset value, the flow rate of the waste heat medium output from the water storage tank is adjusted to complete the dynamic thermal balance compensation process of the target mold during the melting injection stage.

7. The energy-saving molding method based on waste heat recovery management according to claim 1, characterized in that, After the melt injection stage of the target mold, the process of collecting residual heat from mold opening and unloading and utilizing low-grade residual heat is performed, specifically as follows: After the melting and injection stage of the target mold, the pressure holding and shaping of the target equipment is performed, and the target mold is opened for unloading. During the unloading process, the central data analysis unit collects the surface residual temperature data of the demolded molded workpiece and obtains the heat loss of the heat dissipation unit on the workpiece surface, which is used to calculate the low-temperature residual heat of the heat dissipation unit on the workpiece surface. The low-temperature waste heat from the heat dissipation unit on the workpiece surface is transferred to a low-temperature energy storage tank for low-grade waste heat recovery.

8. A molding energy-saving molding system based on waste heat recovery management, characterized in that, The energy-saving molding system integrates a high-performance computing architecture and a data storage module, including a non-volatile memory consisting of a DDR4 RDIMM memory module with ECC verification and an NVMe solid-state storage array using 3D NAND flash memory, and a multi-core processor based on the Zen4 microarchitecture. The memory contains a molding energy-saving molding method program with a molding energy-saving molding engine. When the program is decoded and executed in parallel by the superscalar pipeline execution unit in the processor, it implements the steps of the molding energy-saving molding method based on waste heat recovery management as described in any one of claims 1-7.

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