Sectional type cooling system and method for cooling tank wall of melting furnace
By using a segmented cooling system and control strategy, the problem of balancing cooling effect and energy consumption in traditional cooling methods has been solved, achieving precise matching and high-efficiency energy saving, and improving the safety of the furnace wall and the flexibility of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-07
- Publication Date
- 2026-03-24
AI Technical Summary
Traditional furnace wall cooling methods are difficult to match with the actual heat load of each section, resulting in a trade-off between cooling effect and energy consumption. They also suffer from "overcooling" and "undercooling" problems, and are cumbersome to operate, making it difficult to achieve efficient and precise targeted cooling.
A segmented cooling system is adopted, which accurately measures the pool wall temperature through temperature measuring devices and control units. Combined with the first and second air supply devices, the cooling air volume of the A and B class pool walls is controlled separately. The system adopts dual closed-loop control, feedforward control and adaptive regulation strategies to achieve dynamic response and self-optimization.
It achieves precise matching between cooling air volume and pool wall heat load, reduces energy consumption, improves system flexibility and reliability, has strong dynamic response capability, extends kiln life and reduces maintenance costs.
Smart Images
Figure CN121717540A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of energy saving and process control technology for melting furnaces, specifically to a segmented cooling system and method for cooling the walls of melting furnace pools. Background Technology
[0002] The float glass melting furnace is the core thermal equipment in a float glass production line, and its service life directly affects the company's economic benefits and production efficiency. The tank wall is the area where the batch material is melted into qualified molten glass and comes into direct contact with the molten glass. The operating temperature range is generally 1200-1600℃, and it is a critical part that determines the furnace's lifespan, especially near the liquid level line where corrosion is faster.
[0003] The pool wall bricks near the liquid level are at the interface of solid-liquid-gas phases, and are subjected to long-term erosion by high-temperature molten glass and radiation from flames / fumes, making them a critical weak point affecting kiln life and safety. Their erosion mechanism is closely related to the temperature field and alkaline vapors. Experiments show that temperature is the main factor accelerating the erosion chemical reaction and dissolution; increased temperature increases the diffusion rate between the molten glass and the refractory material. Forced cooling of the pool wall bricks at the liquid level (blowing cooling air) is a common method to extend the service life of the pool wall bricks. Cooling air can effectively reduce the internal temperature of the pool wall bricks and delay erosion, especially in the later stages of kiln operation when increased airflow is required. However, blowing cooling also increases electricity consumption and furnace energy consumption.
[0004] Currently, the common cooling method is to provide cooling air to the outside of the furnace by supplying cooling air to the pool walls. Generally, a bottom fan delivers cold air to each rising branch pipe via a reflux distribution mechanism, and then blows it onto the pool walls at the liquid surface through nozzles. The airflow in each branch pipe is mostly adjusted by manual butterfly valves on the rising branch pipes, and all blowing points draw air from the same reflux distribution mechanism. When the fan is frequency-controlled, the airflow in the entire main air supply line increases or decreases synchronously. This "uniform" air supply pipeline structure simplifies equipment layout, but it is difficult to match the actual heat load distribution inside the furnace.
[0005] For large-tonnage horizontal flame air melting furnaces, there are typically about 10 pairs of smaller furnaces. Each pair has different heat load conditions, resulting in significant differences in the temperature of the inner walls of the furnace sections in contact with the molten glass. If the entire melting zone relies on only one unified air supply: on the one hand, increasing the overall air volume to cover "hot spots" would cause "overcooling" in the front and rear sections, increasing furnace heat dissipation and thus energy consumption; on the other hand, to extend the furnace's lifespan and prevent excessively rapid wall erosion, it is generally necessary to maintain a necessary cooling intensity (cooling air volume) during production operations, ensuring that local areas are not eroded too quickly, without risking a reduction in the overall air supply. Theoretically, this can be compensated for by individually fine-tuning a large number of manual valves, but these valves are mostly located on the operating platform below the high-temperature smaller furnaces (where the ambient temperature is consistently high). Adjusting hundreds of valves at once on-site is cumbersome, and in actual operation, valve positions often remain unchanged for extended periods, making it difficult to dynamically respond to changes in operating conditions.
[0006] The aforementioned structural contradictions make it difficult for traditional pool wall cooling to balance "protecting refractory materials" and "reducing energy consumption." Currently, this traditional, generalized or extensive air-blowing cooling method is unable to achieve efficient and precise targeted cooling in critical erosion areas, and it is also energy-intensive. Summary of the Invention
[0007] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a segmented cooling system and method for cooling the wall of a melting furnace, which can solve the structural contradiction that the traditional "uniform" air supply method is difficult to match with the actual heat load of each section of the melting furnace, resulting in a difficulty in balancing cooling effect and energy consumption.
[0008] To achieve the above objectives, the present invention provides a segmented cooling system for cooling the walls of a melting furnace. The furnace wall comprises multiple wall segments, divided into M Class A segments and N Class B segments. The segmented cooling system includes a temperature measuring device and a control unit. The temperature measuring device is capable of measuring the temperature of each wall segment and is communicatively connected to the control unit. The system also includes a first air supply device and a second air supply device. The first air supply device includes M parallel main air supply mechanisms, each main air supply mechanism comprising a first main fan and a second main fan connected to the first main fan. A first air duct is used to deliver cooling air to the A-class pool wall sections. M main air supply mechanisms are used to supply cooling air to the M A-class pool wall sections respectively. The second air supply device includes a second main fan, a return distribution mechanism connected to the second main fan, and N second air ducts, each connected to the return distribution mechanism. The N second air ducts are used to deliver cooling air to the N B-class pool wall sections respectively. Each second air duct is equipped with an airflow control component for controlling the airflow volume of the second air duct. The control unit is connected to both the first and second air supply devices.
[0009] Furthermore, the first air supply device also includes a first standby fan and a first standby pipe connected to the first standby fan. The first standby pipe has N standby branch pipes, and the N standby branch pipes are respectively connected to the first air ducts of the N main air supply mechanisms. The standby branch pipes are equipped with isolation check valves. The control unit is connected to both the first standby fan and control valve A.
[0010] Furthermore, the second air supply device includes a second standby fan and a second standby pipe, the second standby pipe being connected to the second standby fan and the return flow distribution mechanism; the control unit is connected to the control of the first standby fan.
[0011] Furthermore, the air volume control component includes a regulating control valve and a flow meter, the control unit is connected to the regulating control valve, and the flow meter is communicatively connected to the control unit.
[0012] Furthermore, the temperature measuring device includes multiple wall-mounted temperature measuring components, and each wall-mounted temperature measuring component includes a temperature sensor that is in close contact with the outer surface of the pool wall. Each pool wall segment has at least one wall-mounted temperature measuring component.
[0013] Furthermore, the melting furnace used is a float glass melting furnace with a capacity of 1200–3000 t / d.
[0014] The present invention also provides a segmented cooling method for cooling the walls of a melting furnace, employing the aforementioned segmented cooling system, comprising:
[0015] Class A pool wall segmented cooling method: The control unit adjusts the first main fan of the main air supply mechanism corresponding to each Class A pool wall segment to work according to the temperature of each Class A pool wall segment measured by the temperature measuring device, so that the first air duct outputs cooling air of the corresponding flow rate.
[0016] Segmented cooling method for Class B pool walls: The second main fan of the second air supply device remains operational. The control unit controls the corresponding airflow control component to operate based on the temperature of each Class B pool wall segment measured by the temperature measuring device, so that the second air duct outputs cooling air of the corresponding flow rate.
[0017] Furthermore, both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method employ a dual closed-loop control strategy: for each pool wall segment, a dual closed-loop control is used. The outer loop is a temperature loop based on the pool wall segment temperature, which determines the required target cooling air volume according to the target temperature of the cooling pool wall segment, and outputs the target cooling air volume as the target set value of the inner loop. The inner loop is a flow loop based on the actual cooling air volume output to the pool wall segment and the target set value, which is used to accurately execute changes in the cooling air volume.
[0018] Furthermore, both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method include a feedforward control strategy: the control unit also includes a feedforward module, which is used to receive measurable disturbance variables that affect the temperature change of the pool wall. Based on the measurable disturbance variables, the feedforward module predicts the heat load impact that each pool wall segment will face, and determines the feedforward compensation flow value accordingly, controlling the cooling air volume of the pool wall segment to change, and the change amount is the feedforward compensation flow value.
[0019] Furthermore, both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method include an adaptive control strategy: the control unit is equipped with an adaptive module to establish a dynamic thermal model for each pool wall segment. The adaptive module matches the air volume control parameters based on the relationship between the pool wall segment temperature change and the corresponding cooling air volume in the historical operating data, and controls the change of the cooling air volume corresponding to the pool wall segment according to the air volume control parameters.
[0020] As described above, the segmented cooling system and method of the present invention have the following beneficial effects:
[0021] 1. Precise matching and high efficiency: Through segmented control, the supply of cooling air is precisely matched with the actual heat load of each section of the pool wall, effectively avoiding the problems of "overcooling" and "undercooling" caused by the traditional "uniform" air supply. Under the premise of ensuring the safety of the pool wall, the ineffective heat dissipation and fan power consumption caused by cooling air are significantly reduced.
[0022] 2. Flexible deployment and strong adaptability: It provides two technical routes, namely the first air supply device 1 and the second air supply device 2. It can be deployed independently or in combination according to the heat load characteristics of different areas of the melting furnace, investment budget and other factors. The scheme is highly flexible and suitable for new or technically upgraded melting furnaces of different tonnages and designs.
[0023] 3. High reliability and convenient maintenance: Both the first and second air supply devices are designed with reliable backup fan switching schemes to ensure the continuous and stable operation of the cooling system. When a single section of equipment fails, it will not affect the normal operation of other sections, thus improving the overall reliability and maintainability of the system.
[0024] 4. Automatic control and optimized operation: By using dual closed-loop automatic control based on temperature feedback and flow rate, the cumbersome and slow manual valve adjustment is replaced. It can dynamically respond to changes in operating conditions and always keep the pool wall temperature in the optimal range, thus achieving the dual goals of extending kiln life and saving energy and reducing consumption.
[0025] 5. By using a feedforward control strategy, a compensatory airflow adjustment value is calculated based on the disturbance variable. This "prediction-compensation" mechanism enables the cooling airflow adjustment to be initiated much earlier, suppressing fluctuations in the controlled temperature at the outset and greatly improving the system's dynamic response speed and control stability.
[0026] 6. Through adaptive control strategies, the system achieves self-learning and self-optimization capabilities, ensuring that the cooling system remains in the most efficient and safest working state throughout the entire life cycle of the furnace, whether in the early stages of a new furnace or at the end of its operation. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of the structure of the first air supply device in the segmented cooling system of the present invention.
[0028] Figure 2 This is a schematic diagram of the structure of the second air supply device in the segmented cooling system of the present invention.
[0029] Figure 3 This is a schematic diagram of the wall-mounted temperature measuring component in this invention.
[0030] Explanation of icon numbers:
[0031] 1-First air supply device, 11-First main fan, 12-First air duct, 13-First standby fan, 14-First standby pipe, 141-Standby branch pipe, 15-Isolation check valve, 2-Second air supply device, 21-Second main fan, 22-Manifold, 23-Distribution box, 24-Second air duct, 25-Regulating control valve, 26-Flow meter, 27-Second standby fan, 28-Second standby pipe, 3-Wall-mounted temperature measuring component, 31-Temperature sensor, 32-Gateway box. Detailed Implementation
[0032] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.
[0033] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.
[0034] See Figures 1 to 3 This invention provides a segmented cooling system for cooling the walls of a melting furnace. The melting furnace can be a glass furnace or a furnace producing other products. The furnace wall can be divided into multiple segments from one end to the other, depending on the operating conditions. Specifically, the segmentation can be flexibly determined based on the furnace's tonnage, length, number of furnaces, and thermal characteristics. Each segment covers the wall area corresponding to one or more pairs of furnaces. Based on the actual operating conditions of the melting furnace, the wall segments are divided into M Class A segments and N Class B segments. For example, in a glass furnace, the wall area at the front of the melting zone (corresponding to furnaces #1 to #5) is divided into three Class A segments, and the wall area at the rear of the melting zone (corresponding to furnaces #6 to #9) is divided into multiple Class B segments. Of course, different segmentation methods can be used in other furnaces.
[0035] The segmented cooling system of the present invention includes a temperature measuring device and a control unit. The temperature measuring device is capable of measuring the temperature of each A-class pool wall segment and is communicatively connected to the control unit. It also includes a first air supply device 1 and a second air supply device 2. The first air supply device 1 includes M parallel main air supply mechanisms, each including a first main fan 11 and a first air duct 12 connected to the first main fan 11. The first air duct 12 is used to deliver cooling air for cooling the A-class pool wall segments. The M main air supply mechanisms are respectively used to provide cooling air to the M A-class pool wall segments. The second air supply device 2 includes a second main fan 21, a return distribution mechanism connected to the second main fan 21, and N second air ducts 24, each connected to a second air duct 24. The N second air ducts 24 are used to deliver cooling air to N sections of Class B pool walls for cooling. Each second air duct 24 is equipped with an air volume control component for controlling the air volume delivered by the second air duct 24. The control unit is connected to both the first air supply device 1 and the second air supply device 2 and can control the operation of the first main fan 11, the second main fan 21, and the air volume control component.
[0036] The basic working principle of the segmented cooling system involved in this invention is as follows: The segmented cooling system can cool each segment of the furnace wall separately. The first air supply device 1 is used to cool the A-type wall segment. The control unit adjusts the power of the first main fan 11 of the main air supply mechanism corresponding to each A-type wall segment based on the temperature measured by the temperature measuring device, outputting cooling air at the corresponding flow rate. The A-type wall segment is preferably a region with a non-linear temperature gradient at the front end of the furnace, where the temperature change is large, requiring a large change in air volume. By supplying air through independent first main fans 11, the precise control objective of "energy saving in the low-temperature zone, adaptability in the medium-temperature zone, and strong cooling in the high-temperature zone" is achieved. The second air supply device 2 is used to cool the B-type wall segment. The second main fan 21 of the second air supply device 2 remains operational, continuously supplying air. The control unit adjusts the airflow control component based on the temperature of each B-type wall segment measured by the temperature measuring device and the signal from the flow meter 26 in the corresponding second air duct 24, causing the second air duct 24 to output cooling air at the corresponding flow rate. The cooling air is supplied by a first main fan 11 and distributed to each second air duct 24 through a return flow distribution mechanism. The cooling air volume is precisely controlled. This method can allocate only a small amount of cooling air to non-critical parts as needed, while providing the majority of the cooling air to the most critical parts, thereby providing the most critical parts with the strongest cooling protection and avoiding the waste of a large amount of wind and heat energy in non-critical parts.
[0037] The segmented cooling system of the present invention, through segmented control, sets up two modes: one where the first air supply device 1 supplies air with an independent fan and the other where the first air supply device 1 supplies air with a unified fan. This allows the supply of cooling air to be precisely matched with the actual heat load of each section of the pool wall, effectively avoiding the problems of "overcooling" and "undercooling" caused by the traditional "unified" air supply. Under the premise of ensuring the safety of the pool wall, it significantly reduces the ineffective heat dissipation and fan power consumption caused by the cooling air.
[0038] See Figures 1 to 3 The present invention will be further described below with reference to specific embodiments:
[0039] In this embodiment, see Figure 1 and Figure 3 In the first air supply device 1, each first air duct 12 can be connected to multiple air outlet branches. The air outlet of each air outlet branch can be directed toward different positions of the corresponding Class A pool wall segment, thereby achieving the cooling effect on the Class A pool wall segment.
[0040] In this embodiment, see Figure 1 As a preferred design, the first air supply device 1 further includes a first standby fan 13 and a first standby pipe 14 connected to the first standby fan 13. The first standby pipe 14 has N standby branch pipes 141, which are respectively connected to the first air ducts 12 of the N main air supply mechanisms. Each standby branch pipe 141 is equipped with an isolation check valve 15. Preferably, the control unit is also connected to both the first standby fan 13 and the isolation check valve 15 to control their automatic operation. One or more first standby fans 13 and first standby pipes 14 can be provided. When one or more main air supply mechanisms malfunction, the first standby fan 13 is activated, and the isolation check valve 15 on the standby branch pipe 141 connected to the first air duct 12 of that main air supply mechanism is opened, thereby supplying cooling air to the first air duct 12. Meanwhile, the isolation check valves 15 on the standby branch pipes 141 connected to other normally functioning main air supply mechanisms remain closed.
[0041] In this embodiment, see Figure 2 Each of the second air ducts 24 in the second air supply device 2 can be connected to multiple air outlet branches. The air outlet of each air outlet branch can be directed toward different positions of the corresponding Class B pool wall segment, thereby achieving the cooling effect on the Class B pool wall segment.
[0042] In this embodiment, see Figure 2 The airflow control component includes a regulating control valve 25 and a flow meter 26. The control unit is connected to the regulating control valve 25, and the flow meter 26 is connected to the control unit. Based on the detection signal from the flow meter 26, the control unit adjusts the opening and closing degree of the regulating control valve 25 to output the corresponding cooling airflow. The regulating control valve 25 can be an electro-pneumatic valve.
[0043] In this embodiment, see Figure 2 As a preferred design, the return flow distribution mechanism includes a manifold 22 and a distribution box 23. One end of the manifold 22 is connected to the second main fan 21, and the other end is connected to the distribution box 23. The distribution box 23 has multiple outlets, each of which is connected to a second duct 24.
[0044] In this embodiment, see Figure 2 As a preferred design, the second air supply device 2 includes a second backup fan 27 and a second backup pipe 28. The second backup fan 27 is generally one, but multiple backup fans can also be used. The second backup pipe 28 connects the second backup fan 27 to the manifold 22 of the return distribution mechanism. Preferably, the control unit is also connected to the first backup fan 13 for controlling its automatic operation. When the second main fan 21 fails, the second backup fan 27 is activated, thereby supplying cooling air to the return distribution mechanism and ensuring that each second air duct 24 can normally supply cooling air.
[0045] In this embodiment, see Figure 2 As a preferred design, the first main fan 11, the first standby fan 13, the second main fan 21 and the second standby fan 27 all adopt variable frequency motors and are equipped with frequency converters. The control unit accurately controls the frequency and power of each fan through the frequency converters.
[0046] In this embodiment, see Figure 1 and Figure 3 The temperature measuring device includes multiple wall-mounted temperature measuring components 3. Each wall-mounted temperature measuring component 3 includes a temperature sensor 31, a junction box 32, and a metal protective cover (not shown in the attached drawings). The temperature sensor 31 is attached to the outer surface of the pool wall. The junction box 32 is used for connecting the signal cable of the temperature sensor 31, that is, the temperature sensor 31 transmits signals to the control unit through the junction box 32. The metal protective cover is used to protect the temperature sensor 31. Each pool wall segment has at least one wall-mounted temperature measuring component 3. The temperature of the corresponding pool wall segment can be accurately obtained through the wall-mounted temperature measuring components 3, and the temperature signal can be transmitted to the control unit.
[0047] In this embodiment, see Figure 1 and Figure 3 The control unit can be a programmable logic controller (PLC) with a built-in control algorithm. It can take the set temperature of each pool wall segment as the target value. When the actual temperature fed back by the wall-mounted temperature measuring component 3 is detected to deviate from the target value, it can automatically adjust the first main fan 11 or the regulating control valve 25 to output the corresponding cooling air volume.
[0048] See Figure 1 and Figure 2In this embodiment, the melting furnace is a float glass melting furnace with a capacity of 1200–3000 t / d. Its melting zone has a total of 9 pairs of small furnaces (1#~9#). Under a uniform cooling intensity, the temperature distribution of the furnace wall is uneven along the length direction. The pool wall area at the front end of the melting zone corresponding to small furnaces 1#~5# is divided into three independent Class A pool wall segments. Class A pool wall segment one corresponds to the front of 1# and small furnace 1#, Class A pool wall segment two corresponds to small furnaces 2#~3#, and Class A pool wall segment three corresponds to small furnaces 4#~5#. Correspondingly, the first air supply device 1 is equipped with three main air supply mechanisms to cool the three Class A pool wall segments respectively, so as to realize the refined management of the area with rapid heat load changes. The pool wall area at the rear end of the melting zone, corresponding to furnaces #6 to #9, is divided into two independent Class B pool wall sections. Class B pool wall section one corresponds to furnaces #6 to #7 (continuing the peak high-temperature zone), and Class B pool wall section two corresponds to furnaces #8 to #9 (temperature drop zone). Correspondingly, the second air supply device 2 is equipped with two second air ducts 24 to cool the two Class B pool wall sections respectively. The specific operation of the segmented cooling system is illustrated below:
[0049] Section 1 of Class A pool wall (before No. 1 to No. 1 small furnace): This is the area with the lowest heat load in the melting zone, with a measured temperature of 185℃. To avoid energy waste, the control unit maintains the frequency of the inverter of the corresponding first main fan 11 at a low of 45%, providing only the basic cooling air volume, thus saving a lot of electricity.
[0050] Section 2 of Class A pool wall (small furnaces #2~#3): The heat load increases significantly here, with a measured temperature of 210℃. The control unit increases the frequency of the inverter corresponding to the first main fan 11 to 68% to increase the air volume and suppress further temperature rise.
[0051] Class A pool wall section three (4#~5# small furnaces): This area has entered the peak hot spot zone of the entire kiln, with the measured temperature continuously approaching 220℃. The control unit locks the frequency of the inverter corresponding to the first main blower 11 at 85% to provide the maximum intensity of cooling air, making every effort to ensure the safety of the pool wall at this most dangerous point and prevent it from being rapidly eroded due to overheating.
[0052] Class B pool wall section one (6#~7# small furnaces): This area is the "hot crown zone" with the highest temperature in the entire kiln, and the pool wall temperature is extremely prone to exceeding the limit. The control unit maintains the opening of the regulating control valve 25 in the corresponding second air duct 24 at a large opening of 90%~95%, concentrating most of the air volume here to ensure that the most critical parts receive the strongest cooling protection. Feedback from the flow meter 26 shows that the flow rate in this section is much higher than in other sections.
[0053] Section 2 of Class B pool wall (small furnaces #8~#9): The heat load in this area has decreased significantly, making it a secondary cooling zone. Based on the measured temperature of 195℃, the control unit significantly reduced the opening of the regulating control valve 25 in the corresponding second air duct 24 to 40%, allocating only a small amount of necessary cooling air, thus avoiding the waste of a large amount of air and heat energy in non-critical areas.
[0054] See Figure 1 and Figure 2 The present invention also provides a segmented cooling method for cooling the walls of a melting furnace, employing the aforementioned segmented cooling system, comprising:
[0055] The Class A pool wall segmented cooling method: The control unit adjusts the power of the first main fan 11 of the main air supply mechanism corresponding to each Class A pool wall segment based on the temperature measured by the temperature measuring device, so that the first air duct 12 outputs cooling air at the corresponding flow rate. During the adjustment process, a flow detector can also be installed on the first air duct 12, or the flow feedback module built into the first main fan 11 can be used to determine the output air volume of the first air duct 12 at this time, and the adjustment can be made based on this feedback.
[0056] Segmented cooling method for Class B pool walls: The second main fan 21 of the second air supply device 2 remains operational, continuously supplying air to the return flow distribution mechanism. The control unit, based on the temperature of each Class B pool wall segment measured by the temperature measuring device, controls the airflow control component in the corresponding second air duct 24 to operate, causing the second air duct 24 to output cooling air at the corresponding flow rate. Specifically, the control unit determines the required airflow based on the temperature of each Class B pool wall segment, and controls the opening and closing degree of the regulating control valve 25 based on the feedback signal from the flow meter 26 in the airflow control component, thereby causing the second air duct 24 to output cooling air at the corresponding flow rate.
[0057] As a preferred design, both Type A and Type B segmented cooling methods employ dual closed-loop control for the cooling of each segment. The outer loop is a temperature loop based on the segment's temperature, determining the required target cooling airflow based on the target temperature to be achieved and using its output as the target setpoint for the inner loop. The inner loop is a flow loop based on the actual cooling airflow output to the segment and the target setpoint, used to precisely control changes in cooling airflow. Specifically, for the first air supply device 1, the inner loop is a flow loop based on the signal from the first main fan 11 or an additionally installed flow detector and the target setpoint, controlling the airflow and rate of change of the first main fan 11 accordingly. For the second air supply device 2, the inner loop is a flow loop based on the signal from the flow meter 26 and the target setpoint, controlling the opening and closing degree and rate of change of the regulating control valve 25 accordingly.
[0058] As a preferred design, a feedforward control strategy is also adopted on the basis of dual closed-loop control: the control unit also includes a feedforward module, which is used to receive measurable disturbance variables that affect the temperature change of the furnace wall. Specifically, it can be connected to sensor signals used to monitor the operating status of the melting furnace. Measurable disturbance variables can be various types of variables, including but not limited to the fuel flow rate or combustion air flow rate of the corresponding furnace in the furnace wall segment. Taking the fuel flow rate of the corresponding furnace as an example, when the fuel flow rate changes, it means that the combustion intensity in the furnace is about to change, which will lead to a change in the furnace wall temperature. The feedforward module predicts the heat load impact that each furnace wall segment will face based on the measurable disturbance variables, and determines the feedforward compensation flow rate value accordingly, controlling the change in the cooling air volume of the furnace wall segment. The change is the feedforward compensation flow rate value. The process of predicting the heat load impact that each furnace wall segment will face based on the measurable disturbance variables and determining the feedforward compensation flow rate value accordingly can be automatically calculated by pre-setting a mathematical model in the feedforward module. The obtained feedforward compensation flow rate value can be superimposed on the output of the temperature loop, that is, the value input to the inner loop is the target cooling airflow plus the feedforward compensation flow rate value. This "prediction-compensation" mechanism enables the adjustment of cooling airflow to be initiated much earlier, suppressing fluctuations in the controlled temperature at their inception, and greatly improving the dynamic response speed and control stability of the system.
[0059] Furthermore, considering that a glass melting furnace is a slow-time-varying system with an operating cycle of several years or even more than ten years, its pool walls gradually thin due to the long-term erosion of molten glass, leading to fundamental changes in its thermal properties such as heat transfer coefficient and heat capacity. This results in a change in the required cooling airflow for the same target temperature. To address this issue, as a preferred design, this method also employs an adaptive control strategy: the control unit is equipped with an adaptive module. This module establishes a dynamic thermal model for each pool wall segment based on the dynamic response relationship between temperature changes in different pool wall segments and the corresponding cooling airflow from historical operating data. This dynamic thermal model is updated in real time during operation, thus obtaining the response sensitivity of each pool wall segment to changes in cooling airflow. Based on this, airflow control parameters are matched, and the changes in cooling airflow corresponding to each pool wall segment are controlled according to these parameters. Specifically, the adaptive module possesses online system identification capabilities. It can periodically, or under triggered conditions, analyze the response data relationship between the pool wall temperature and the corresponding cooling airflow based on operational data from a previous period at the current time point. This allows it to "learn," establish, and update a dynamic thermal model that accurately describes the current pool wall state. Subsequently, based on this latest model, the adaptive module automatically retunes and optimizes the PID parameters of the temperature control loop, thereby adjusting the cooling airflow accordingly. For example, in areas with severe erosion (e.g., furnaces #4-#5), where heat transfer is faster (process gain is greater), the adaptive module automatically adjusts to a more gradual set of control parameters to prevent overshoot and oscillation. Conversely, for pool wall segments with less erosion and slower response (e.g., furnaces #6-#7), more rapid-response parameters are matched, achieving differentiated and precise control for different areas. This self-learning and self-optimization capability enables the segmented cooling system of this invention to proactively adapt to time-varying thermal characteristics caused by factors such as kiln age and pool wall erosion throughout the entire lifecycle of the furnace, maintaining optimal control performance and safety whether in the initial stages of a new kiln or at the end of its operation.
[0060] As can be seen from the above, the segmented cooling system and method of the present invention have the following beneficial effects:
[0061] 1. Precise matching and high efficiency: Through segmented control, the supply of cooling air is precisely matched with the actual heat load of each section of the pool wall, effectively avoiding the problems of "overcooling" and "undercooling" caused by the traditional "uniform" air supply. Under the premise of ensuring the safety of the pool wall, the ineffective heat dissipation and fan power consumption caused by cooling air are significantly reduced.
[0062] 2. Flexible deployment and strong adaptability: It provides two technical routes, namely the first air supply device 1 and the second air supply device 2. It can be deployed independently or in combination according to the heat load characteristics of different areas of the melting furnace, investment budget and other factors. The scheme is highly flexible and suitable for new or technically upgraded melting furnaces of different tonnages and designs.
[0063] 3. High reliability and convenient maintenance: Both the first air supply device 1 and the second air supply device 2 are designed with reliable backup fan switching schemes to ensure the continuous and stable operation of the cooling system. When a single section of equipment fails, it will not affect the normal operation of other sections, thus improving the overall reliability and maintainability of the system.
[0064] 4. Automatic control and optimized operation: By using dual closed-loop automatic control based on temperature feedback and flow rate, the cumbersome and slow manual valve adjustment is replaced. It can dynamically respond to changes in operating conditions and always keep the pool wall temperature in the optimal range, thus achieving the dual goals of extending kiln life and saving energy and reducing consumption.
[0065] 5. By using a feedforward control strategy, a compensatory airflow adjustment value is calculated based on the disturbance variable. This "prediction-compensation" mechanism enables the cooling airflow adjustment to be initiated much earlier, suppressing fluctuations in the controlled temperature at the outset and greatly improving the system's dynamic response speed and control stability.
[0066] 6. Through adaptive control strategies, the system achieves self-learning and self-optimization capabilities, ensuring that the cooling system remains in the most efficient and safest working state throughout the entire life cycle of the furnace, whether in the early stages of a new furnace or at the end of its operation.
[0067] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.
[0068] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.
Claims
1. A segmented cooling system for cooling the walls of a melting furnace, wherein the furnace wall comprises multiple wall segments, and is divided into M Class A wall segments and N Class B wall segments, the segmented cooling system comprising a temperature measuring device and a control unit, the temperature measuring device being capable of measuring the temperature of each wall segment, and the temperature measuring device being communicatively connected to the control unit, characterized in that: It also includes a first air supply device (1) and a second air supply device (2). The first air supply device (1) includes M main air supply mechanisms arranged in parallel, and the main air supply mechanism includes a first main fan (11) and a first air duct (12) connected to the first main fan (11). The first air duct (12) is used to transport cooling air to cool the Class A pool wall sections. The M main air supply mechanisms are used to supply cooling air to the M Class A pool wall sections respectively. The second air supply device (2) includes a second main fan (21), a return flow distribution mechanism connected to the second main fan (21), and N second air ducts (24) connected to the return flow distribution mechanism respectively. The N second air ducts (24) are used to transport cooling air to cool the N Class B pool wall sections respectively. Each second air duct (24) is provided with an air volume control component for controlling the air volume of the second air duct (24). The control unit is controlled and connected to both the first air supply device (1) and the second air supply device (2).
2. The segmented cooling system according to claim 1, characterized in that: The first air supply device (1) further includes a first standby fan (13) and a first standby pipe (14) connected to the first standby fan (13). The first standby pipe (14) has N standby branch pipes (141), and the N standby branch pipes (141) are respectively connected to the first air pipes (12) of the N main air supply mechanisms. The standby branch pipes (141) are equipped with isolation check valves (15). The control unit is connected to both the first standby fan (13) and the control valve A.
3. The segmented cooling system according to claim 1, characterized in that: The second air supply device (2) includes a second standby fan (27) and a second standby pipe (28), the second standby pipe (28) being connected to the second standby fan (27) and the return flow distribution mechanism; the control unit is connected to the first standby fan (13) for control.
4. The segmented cooling system according to claim 1, characterized in that: The air volume control component includes a regulating control valve (25) and a flow meter (26). The control unit is connected to the regulating control valve (25) and the flow meter (26) is connected to the control unit.
5. The segmented cooling system according to claim 1, characterized in that: The temperature measuring device includes multiple wall-mounted temperature measuring components (3), and the wall-mounted temperature measuring components (3) include a temperature sensor (31) that is in close contact with the outer surface of the pool wall. Each pool wall segment has at least one wall-mounted temperature measuring component (3).
6. The segmented cooling system according to claim 1, characterized in that: The melting furnace used is a float glass melting furnace with a capacity of 1200–3000 t / d.
7. A segmented cooling method for cooling the walls of a melting furnace, characterized in that: The segmented cooling system as described in any one of claims 1 to 4 is used, comprising: A-class pool wall segmented cooling method: The control unit adjusts the first main fan (11) of the main air supply mechanism corresponding to each A-class pool wall segment to work according to the temperature of each A-class pool wall segment measured by the temperature measuring device, so that the first air duct (12) outputs cooling air of the corresponding flow rate. Class B pool wall segmented cooling method: The second main fan (21) of the second air supply device (2) keeps working, and the control unit controls the corresponding air volume control component to work according to the temperature of each Class B pool wall segment measured by the temperature measuring device, so that the second air duct (24) outputs cooling air of the corresponding flow rate.
8. The segmented cooling method according to claim 7, characterized in that: Both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method employ a dual closed-loop control strategy: Each pool wall segment employs dual closed-loop control. The outer loop is a temperature loop based on the pool wall segment temperature, which determines the required target cooling airflow according to the target temperature of the cooling pool wall segment and uses the target cooling airflow output as the target setpoint for the inner loop. The inner loop is a flow loop based on the actual cooling airflow output to the pool wall segment and the target setpoint, used to precisely execute changes in cooling airflow.
9. The segmented cooling method according to claim 7, characterized in that: Both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method further include: Feedforward control strategy: The control unit also includes a feedforward module, which is used to receive measurable disturbance variables that affect the temperature change of the pool wall. Based on the measurable disturbance variables, the feedforward module predicts the heat load impact that each pool wall segment will face, and determines the feedforward compensation flow value accordingly. It controls the cooling air volume of the pool wall segment to change, and the change is the feedforward compensation flow value.
10. The segmented cooling method according to claim 7, characterized in that: Both the Class A pool wall segmented cooling method and the Class A pool wall segmented cooling method further include: Adaptive control strategy: The control unit is equipped with an adaptive module to establish a dynamic thermal model for each pool wall segment. The adaptive module matches the air volume control parameters based on the relationship between the temperature change of the pool wall segment and the corresponding cooling air volume in the historical operating data, and controls the change of the cooling air volume corresponding to the pool wall segment according to the air volume control parameters.