A method for improving the homogenization quality of glass melt

Abstract

The present invention provides a method for improving the homogenization quality of molten glass, belonging to the technical field of glass production. The method includes the following steps: selecting a measurement position in a glass melting furnace; obtaining the flow direction and flow velocity of the molten glass at different depths at the measurement position in the glass melting furnace under the condition of stable production conditions, stable glass output and quality as standard reference data; in actual production, measuring the actual flow direction and actual flow velocity of the molten glass at different depths at the measurement position in the glass melting furnace, and comparing with the standard reference data to determine whether the change trend of the flow direction, flow velocity or both of the molten glass at the measurement position is consistent with the standard reference data. The present invention selects the key parts of the melting furnace to obtain the flow parameters of the molten glass among the flow parameters of the molten glass, and adjusts the relevant process parameters according to the real-time detection results to realize the standardized and precise control of the molten glass flow at the key parts.

Description

Technical Field

[0001] The present invention belongs to the technical field of glass production, and particularly relates to a method for improving the homogenization quality of glass liquid. Background Art

[0002] In the production process of flat glass, glass raw materials are made into a batch that meets the requirements according to the designed composition, and then put into a glass tank furnace for melting, clarification, and homogenization to form glass liquid that meets the quality requirements. After forming and annealing, commercial flat glass is produced. Among them, forming pure, uniform, and suitable glass liquid from the batch is a key link in glass manufacturing. Most glass defects such as bubbles and impurities that cause a reduction in the yield rate are generated in this stage.

[0003] The occurrence of glass quality defects is mainly due to poor homogenization quality during the melting process of glass. The melting process of glass is very complex and affected by many factors. However, it has been found that all these influencing factors can be reflected through the flow state of the glass liquid, thereby affecting the homogenization quality of the glass liquid. However, due to the characteristics of high temperature and airtightness of the glass melting furnace, the high temperature of about 1700 °C in the space and the airtight space structure, coupled with continuous physical and chemical reactions, it is very difficult for people to directly observe the flow law of the glass liquid inside the melting furnace. For a long time, through the use of mathematical simulation and physical simulation methods, it has been found that the flow state of the glass liquid in the glass melting furnace forms two major circulation flows along the length direction of the furnace from the front charging tank to the discharge port in a continuously operating tank furnace, namely the production flow flowing towards the end and the return flow flowing back towards the furnace head direction. However, in actual production, people have not directly detected the flow state of the two major return flows, so there is still a lack of timely and effective methods for detecting and precisely controlling the flow pattern of the glass liquid in the glass melting furnace.

[0004] After studying the flow law of the glass liquid in the melting furnace, relevant technical personnel in this field believe that the product glass implicitly contains the flow state of the glass liquid during the melting of the front-end glass. That is, when observing the end face of a transverse glass section parallel to the drawing direction using relevant optical instruments, stripes of the flat glass can be seen, and the stripe characteristics reflect the operating characteristics of the glass during melting. Therefore, an end-face stripe image analyzer has been developed to collect glass samples, conduct measurements, analyze the obtained stripe images, and then analyze the possible causes according to the liquid flow law. The obtained results are then reversed to the relevant parts related to the liquid flow characteristics in the melting furnace, so as to find out the parts and process-related reasons for the generation of non-uniform glass liquid, and make fine adjustments to the corresponding parts to achieve the goal of stable production.

[0005] This solution indirectly proposes a method to improve the homogenization quality of molten glass by analyzing the stripes on the end face of glass products. However, there is an obvious lag in this method. Therefore, there is still a lack of effective methods for timely detection and precise control of the flow pattern of molten glass in the glass furnace. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for improving the homogenization quality of molten glass in view of the deficiencies of the prior art.

[0007] To solve the above technical problem, the technical solution adopted by the present invention is as follows:

[0008] A method for improving the homogenization quality of molten glass, comprising the following steps:

[0009] Select measurement positions in the glass melting furnace;

[0010] Under the condition of stable production conditions, stable glass output and quality, obtain the flow direction and flow velocity of molten glass at different depths at the measurement positions in the glass melting furnace as standard reference data;

[0011] In actual production, measure the actual flow direction and actual flow velocity of molten glass at different depths at the measurement positions in the glass melting furnace, and compare them with the standard reference data to determine whether the change trend of the flow direction, flow velocity or both of the molten glass at the measurement positions is consistent with the standard reference data; if they are consistent, maintain the current flow direction and flow velocity of the molten glass; if they are not consistent, adjust the corresponding process parameters to make the actual flow direction and actual flow velocity of the molten glass consistent with the standard reference data.

[0012] Preferably, there are multiple measurement positions, which are located on the production line from the throat water pocket to the end of the cooling section and are distributed along the length direction of the glass melting furnace and the longitudinal center line of the molten glass.

[0013] Preferably, the measurement positions are respectively: near the throat water pocket, at the midpoint of the longitudinal center line length of the cooling section, and near the flow port at the end of the cooling section.

[0014] Preferably, at the position near the throat water pocket, the different depths of the forward flow layer are selected as 400 - 595 mm, and the different depths of the backflow layer are selected as 605 - 800 mm;

[0015] At the midpoint of the longitudinal center line length of the cooling section, the different depths of the forward flow layer are selected as 50 - 395 mm, and the different depths of the backflow layer are selected as 405 - 800 mm;

[0016] At the tail end of the cooling section near the flow port, different depths of the forward flow layer are selected to be 10 - 300 mm, and different depths of the backflow layer are selected to be 355 - 740 mm.

[0017] Preferably, a high-temperature flow velocity detection device is installed at the measurement position to measure the flow velocity of the glass liquid at different depths at the measurement position.

[0018] Preferably, the high-temperature flow velocity detection device includes: a high-temperature flow velocity measurement module, a data analysis and processing module, a display module, a cooling protection module, a lifting module, and a power supply module. The high-temperature flow velocity measurement module is connected to the data analysis and processing module, the data analysis and processing module is connected to the display module, the cooling protection module is arranged outside the data analysis and processing module, the lifting module is connected to the outside of the cooling protection module, and the power supply module is connected to the power supply ends of the high-temperature flow velocity measurement module, the data analysis and processing module, the display module, and the lifting module; based on the above solution, the flow state of the glass liquid flowing into the throat can be monitored in a timely manner and precisely controlled.

[0019] Among them, the high-temperature flow velocity measurement module includes a flow velocity detection probe, and the flow velocity detection probe adopts a high-temperature-resistant flow velocity detection probe;

[0020] The data analysis and processing module includes an AD module, a single-chip microcomputer, and a data sending port, and is used for processing the data obtained by the high-temperature flow velocity measurement module;

[0021] The display module includes a display terminal and a data receiving port, and is used for displaying the data obtained by the data analysis and processing module;

[0022] The cooling protection module includes a cooling cover and a cooling medium arranged in the cooling cover. The cooling medium is communicated with a cooling source and is used to protect the data analysis and processing module from being damaged by high temperature.

[0023] Combined with the on-site operation environment, the high-temperature flow velocity detection device is fixed above the melting furnace. The cooling protection module protects the data analysis and processing module except the flow velocity detection probe from being damaged by high temperature. The lifting module ensures that the flow velocity detection probe of the high-temperature flow velocity measurement module can be lifted and lowered in the glass liquid as needed to measure the flow velocity of the glass liquid in different depth directions at a preset position. The data analysis and processing module transmits the glass liquid flow velocity data collected by the high-temperature flow velocity measurement module to the display module in the control room.

[0024] Preferably, the inconsistent situations include at least one of the following ways: inconsistent flow directions, inconsistent flow velocities, and inconsistent change trends of flow velocities.

[0025] Preferably, the adjustment of the corresponding process parameters includes at least one of the following ways: adjusting the pressing depth of the throat water pocket and adjusting the dilution air intensity of the cooling section.

[0026] Glass melting furnaces are characterized by high temperature and airtightness. Coupled with the continuous physical and chemical reactions occurring, it is very difficult for people to directly observe the flow law of the molten glass inside the furnace. Although the flow state of the molten glass in the glass melting furnace is crucial for the homogenization quality of the glass, people still have not directly detected the flow state of the molten glass and precisely controlled the flow state of the molten glass flow.

[0027] Based on comprehensive literature reports and actual production situations in various aspects, it can be known that the motion state of the molten glass in the glass melting furnace is very complex, and the motion characteristics of the molten glass in each part of the furnace vary widely and are difficult to grasp. The main problems encountered in the research and development of the present invention are precisely the determination of the flow state of the molten glass in the furnace and the establishment of the motion characteristics and detection methods of the key parts.

[0028] Through countless production line simulation tests and combined with decades of production experience, the present invention discovers that along the length direction of the glass melting furnace, the molten glass forms two stable forward flow layers and reverse flow layers with opposite motion directions along the depth direction on the longitudinal center line from the neck water pocket to the flow port at the end of the cooling section. The thickness and flow velocity of the forward flow layer and the reverse flow layer at each position along the length direction of the furnace show regular changes with the variation of production process conditions, thus affecting the homogenization quality of the molten glass. The present invention selects the flow velocity of the molten glass at the key parts of the furnace among the flow parameters of the molten glass for timely monitoring, and adjusts relevant process parameters according to the detection results to achieve standardized and precise control of the molten glass flow at the key parts.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] Through in-depth research on the flow pattern of the molten glass in the glass melting furnace, the present invention proposes that in order to improve the homogenization quality of the molten glass, it is necessary to have an excellent and stable flow state of the molten glass in the furnace as a production technical feature, and further proposes and implements an implementation plan for timely monitoring and standardized precise control of the flow state of the molten glass flowing into the neck.

[0031] Through timely detection and rapid and timely adjustment of the molten glass flow, the present invention ensures that two stable forward flow layers and reverse flow layers with opposite motion directions are formed along the depth direction from the neck cooling water pocket to the flow port at the end of the cooling section, and the thickness and flow velocity of the forward flow layer and the reverse flow layer at the characteristic positions can be kept unchanged, enabling the molten glass flow to enter the working section in a stable laminar flow state and enabling the molten glass to maintain good uniformity and enter the next process. The use of this technology avoids the lag that occurs when the molten glass flow in the melting furnace has already fluctuated greatly and only then, due to the inability to detect and take corresponding measures in a timely manner, leads to serious defects in the glass, and then reasoning and analysis are carried out to find the cause of the problem and the molten glass flow is adjusted. The entire process is long and lagging, causing greater losses to production.

[0032] In the present invention, along the length direction of the glass melting furnace and on the longitudinal center line, several positions are selected from the throat towards the launder direction in the glass melting furnace, and a set of high-temperature flow velocity detection devices are respectively arranged at each position. The present invention preferably selects three positions. The first position is installed close to the throat water pocket, and it can be either in front of or behind the throat water pocket, preferably within 100 m. If conditions permit, the closer to the throat water pocket, the better, so as to accurately obtain the forward flow and reflux information of the glass liquid under the throat water pocket, and provide a scientific basis for the process operation of the throat water pocket and the adjustment of the corresponding heat load. The second position is located at half of the longitudinal center line of the cooling section to obtain the flow information of the glass liquid flow in the cooling section, and can provide a scientific basis for the process adjustment of the cooling water pocket and dilution air in the cooling section. The third position is located at the end of the cooling section near the launder part, which can provide a basis for the change of the glass drawing rate.

[0033] The high-temperature flow velocity detection device adopted by the present invention includes a high-temperature flow velocity measurement module, a data analysis and processing module, a display module, a cooling protection module, a lifting module and a power supply module to realize the timely monitoring and standardized precise control of the flow state of the glass liquid flowing into the throat. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0035] Figure 1 : Flow velocity distribution diagram of the glass liquid;

[0036] Figure 2 : Schematic diagram of the control method of the glass liquid before and after the throat water pocket;

[0037] Figure 3 : Schematic diagram of the structure of the high-temperature flow velocity detection device;

[0038] Among them, 1 - throat water pocket, 2 - glass liquid, 3 - forward flow layer, 4 - reflux layer, 5 - launder opening, 6 - high-temperature flow velocity detection device, 7 - flow velocity detection probe, 8 - data analysis and processing module, 9 - display module, 10 - cooling cover, 11 - lifting module. Detailed Embodiments

[0039] To better understand the present invention, the content of the present invention will be further clearly elaborated below in conjunction with embodiments. However, the protected content of the present invention is not limited to the following embodiments. In the following description, a large number of specific details are given to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of steps, operations, devices, components, and / or combinations thereof.

[0041] Unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that for the convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the said technologies, methods, and devices should be regarded as part of the authorized specification.

[0042] As Figure 1 shown, through mathematical simulation, physical simulation, and combined with the practical experience of long-term glass production, the present invention discovers that in the glass melting furnace, the glass liquid 2 flowing from the neck water pocket 1 to the flow port 5 at the end of the cooling section forms two forward flow layers 3 and reverse flow layers 4 moving in opposite directions along the depth direction.

[0043] During production, when the working conditions fluctuate, the flow velocity and flow direction of the glass liquid 2 in these two reverse flows will change at fixed positions, resulting in a change in the homogenization effect of the glass liquid 2 and ultimately causing a decrease in the quality of the glass products. However, for a long time, glass producers have only speculated on the change characteristics of the glass liquid flow when the glass quality changes, and then adjusted the relevant process parameters to make the glass liquid flow return to the normal and stable state again.

[0044] In order to effectively solve the above problems, the present invention proposes a method for improving the homogenization quality of glass liquid, adopting the timely detection and precise control technology of the flow pattern of the glass liquid in the glass furnace, so as to timely detect the flow state of the glass liquid 2 in the melting furnace. When the change in the liquid flow velocity at the key position exceeds the reference value, combined with the process parameters and production conditions of the entire melting furnace, the relevant parameters can be quickly adjusted to quickly achieve the uniformity and stability of the glass liquid flow.

[0045] A method for improving the homogenization quality of glass liquid, comprising the following steps:

[0046] Select a measurement position inside the glass melting furnace; under the condition of stable production operation, stable glass output and quality, obtain the flow direction and flow velocity of the glass liquid 2 at different depths at the measurement position inside the glass melting furnace as standard reference data;

[0047] During actual production, measure the actual flow direction and actual flow velocity of the glass liquid 2 at different depths at the measurement position inside the glass melting furnace, and compare with the standard reference data to determine whether the flow direction, flow velocity or the change trend of both of the glass liquid 2 at the measurement position is consistent with the standard reference data; if consistent, maintain the current flow direction and flow velocity of the glass liquid 2; if not consistent, adjust the corresponding process parameters to make the actual flow direction and actual flow velocity of the glass liquid 2 consistent with the standard reference data.

[0048] As Figure 2 shown, it is a schematic diagram of the precise control method of the glass liquid flow after the throttle water pocket 1. In order to improve the homogenization quality of the glass liquid 2, the present invention selects several positions along the length direction of the glass melting furnace on the longitudinal center line starting from the throttle water pocket 1 towards the flow port 5. As Figure 2 at position A, position B and position C in, a set of high-temperature flow velocity detection device 6 is respectively arranged at each position.

[0049] As Figure 3 shown, the high-temperature flow velocity detection device 6 includes: a high-temperature flow velocity measurement module, a data analysis and processing module 8, a display module 9, a cooling and protection module, a lifting module 11 and a power supply module. The high-temperature flow velocity measurement module is connected to the data analysis and processing module 8, the data analysis and processing module 8 is connected to the display module 9, the cooling and protection module is arranged outside the data analysis and processing module 8, the lifting module 11 is connected to the outside of the cooling and protection module, and the power supply module is connected to the power supply ends of the high-temperature flow velocity measurement module, the data analysis and processing module 8, the display module 9 and the lifting module 11; based on the above solution, the flow state of the glass liquid 2 flowing into the throttle is monitored in a timely manner and precisely controlled.

[0050] Among them, the high-temperature flow velocity measurement module includes a flow velocity detection probe 7, and the flow velocity detection probe 7 adopts a high-temperature resistant flow velocity detection probe 7;

[0051] The data analysis and processing module 8 includes an AD module, a single-chip microcomputer and a data sending port. The single-chip microcomputer is connected to the flow velocity detection probe 7, the AD module is connected to the single-chip microcomputer, and the single-chip microcomputer is connected to the data sending port, and is used for analyzing and processing the data obtained by the high-temperature flow velocity measurement module;

[0052] The display module 9 includes a display terminal and a data receiving port. The data receiving port is connected to the data sending port, and the display terminal is connected to the data receiving port for displaying the data obtained by the data analysis and processing module 8.

[0053] The cooling protection module includes a cooling cover 10 and a cooling medium arranged inside the cooling cover 10. The cooling medium is communicated with a cooling source and is used to protect the data analysis and processing module 8 from being damaged by high temperature. The cooling cover 10 is made of high-temperature resistant materials.

[0054] The lifting module 11 can select a lifting device, and the lifting column of the lifting device is connected to the outside of the cooling cover 10.

[0055] Combined with the on-site operation environment, the high-temperature flow rate detection device 6 is fixed above the melting furnace. The cooling protection module protects the high-temperature flow rate measurement module except the flow rate detection probe 7 and the data analysis and processing module 8 from being damaged by high temperature. The lifting module 11 ensures that the flow rate detection probe 7 of the high-temperature flow rate measurement module can move up and down in the glass liquid 2 as needed to measure the flow velocity of the glass liquid 2 in different depth directions at the set position. The data analysis and processing module 8 transmits the glass liquid flow rate data collected by the high-temperature flow rate measurement module to the display module 9 in the control room.

[0056] In the process of glass production, the present invention installs a high-temperature flow rate detection device 6 at the measurement position to obtain standard reference data on the flow direction and flow velocity of the glass liquid 2 at different depths at the measurement position. The specific operation steps are as follows: Select a production condition with stable production, where both the glass output and quality are high and stable. Insert the high-temperature flow rate detection device 6 vertically downward below the liquid level of the glass liquid 2, continuously adjust the insertion depth, continuously measure and record the flow direction and flow velocity of the glass liquid 2 at different depths. After taking the average value of the repeatedly measured data, determine the parameters of the flow direction and flow velocity of the glass liquid 2.

[0057] In actual production, measure the flow direction and flow velocity of the glass liquid at the specified frequency, immediately obtain the actual flow characteristic data of the glass liquid, and quickly adjust the relevant processes according to the change characteristics of the glass output and quality to complete the real-time monitoring and precise control of the flow state of the glass liquid 2 flowing into the throat, thereby improving the homogenization quality of the glass liquid 2.

[0058] Embodiment 1

[0059] Select to install a set of high-temperature flow rate detection devices 100 mm in front of the throat water pocket 1 on the longitudinal center line of the glass melting furnace to determine the operation reference standard of the glass liquid at this position. By examining the output and quality of the glass, select multiple dates with high glass output and quality and stable production (i.e., excellent production dates), detect the flow condition of the glass liquid at this position, and take the average value as the operation reference standard of the glass liquid at this position.

[0060] Step 1: Select 10 excellent production dates, collect the flow direction and flow velocity of the molten glass as reference standards. When collecting daily, start from 5 mm below the molten glass surface, gradually adjust the depth of the detection probe inserted into the molten glass surface downward, and record the depth of the probe from the molten glass surface and the corresponding flow velocity and flow direction of the glass at each inserted depth. Record the direction of the molten glass flowing towards the end of the production line (i.e., the production flow) as positive, and record the direction of the molten glass flowing towards the kiln head of the production line (i.e., the backflow) as negative. Take the average of the flow velocities at the same depth over 10 days as the standard reference data at 100 mm in front of the throttle water pocket 1 on the longitudinal center line of the melting furnace.

[0061] Step 2: During actual production, detect the flow condition of the molten glass on time every day, obtain the actual flow direction and actual flow velocity of the molten glass, compare the actual measurement data with the standard reference values, and judge whether the flow direction and flow velocity of the molten glass at the measurement position and the change trend of the two are consistent with the standard reference data according to the comparison result; if they are consistent, maintain the current flow direction and flow velocity of the molten glass; if they are not consistent, adjust the corresponding process parameters to make the actual flow direction and actual flow velocity of the molten glass consistent with the standard reference data.

[0062] Table 1 shows the standard reference data at 100 mm in front of the throttle water pocket 1 on the longitudinal center line of a float glass production line. Table 2 shows the measurement results of the actual flow direction and actual flow velocity during a production fluctuation.

[0063] Table 1 Reference Standard for the Flow Velocity of the Deep Molten Glass at 100 mm in Front of the Throttle Water Pocket 1

[0064] Depth (mm) 405 410 440 470 535 555 595 Speed reference value (mm / min) ＋41 ＋79.8 ＋268 ＋382.2 ＋368.6 ＋293 ＋16.6 Depth (mm) 605 610 640 670 735 755 798 Speed reference value (mm / min) -34.1 -66.5 -224 -318.5 -307.1 -244.1 -13.9

[0065] Table 2 Flow Velocity of the Deep Molten Glass at 100 mm in Front of the Throttle Water Pocket 1

[0066] Depth (mm) 405 410 440 470 535 555 595 Speed (mm / min) ＋43 ＋83.8 ＋281 ＋401 ＋387 ＋307.7 ＋17.43 Depth (mm) 605 610 640 670 735 755 798 Speed (mm / min) -34.1 -66.5 -224 -318.5 -307.1 -244.1 -13.9

[0067] Comparing the measured flow velocity of the molten glass with the reference standard, it is found that the forward flow velocity (i.e., the positive flow velocity) of the molten glass at 100 mm in front of the throttle water pocket 1 has increased. If not processed in time, it will cause a change in the flow state of the molten glass entering the cooling section and reduce the homogenization quality of the molten glass. After adjusting the pressing depth of the throttle water pocket 1 and the heat load of the side furnace, the flow velocity of the molten glass is measured again, and the flow velocity gradually returns to the normal state, and the product quality of the glass is maintained at the normal level, thus avoiding the generation of glass defects.

[0068] Example 2

[0069] Select a position at half of the longitudinal centerline length of the cooling section of the melting furnace to install a set of high-temperature flow rate detection devices to determine the operating reference standard of the glass liquid at this location. By examining the output and quality of the glass, select multiple dates with relatively high glass output and quality and stable production (i.e., excellent production dates), detect the flow condition of the glass liquid at this location, and take the average value as the operating reference standard of the glass liquid at this location.

[0070] Step 1: Select 10 excellent production dates, collect the flow direction and flow rate of the glass liquid as the reference standard. When collecting daily, start from 5 mm below the glass liquid surface, gradually adjust the depth of the detection probe inserted into the glass liquid surface downward, and record the depth of the probe from the glass liquid surface and the corresponding flow rate and flow direction of the glass every time a certain depth is inserted. Record the direction of the glass liquid flowing towards the end of the production line (i.e., the production flow) as positive, and record the direction of the glass liquid flowing towards the kiln head of the production line (i.e., the backflow) as negative. Take the average value of the flow rate values at the same depth for 10 days as the standard reference data at the position of half of the longitudinal centerline length of the cooling section.

[0071] Step 2: During actual production, detect the flow condition of the glass liquid on time every day, obtain the actual flow direction and actual flow rate of the glass liquid, compare the actual measurement data with the standard reference values, and judge whether the flow direction and flow rate of the glass liquid at the measurement position and the change trend of the two are consistent with the standard reference data according to the comparison results; if they are consistent, maintain the current flow direction and flow rate of the glass liquid; if they are not consistent, adjust the corresponding process parameters to make the actual flow direction and actual flow rate of the glass liquid consistent with the standard reference data.

[0072] Table 3 shows the standard reference data at the position of half of the longitudinal centerline length of the cooling section of one float glass production line. Table 4 shows the measurement results of the actual flow direction and actual flow rate during a production fluctuation.

[0073] Table 3 Reference standard for the flow rate of the glass liquid at the position of half of the longitudinal centerline length of the cooling section

[0074] Depth (mm) 50 105 148 185 252 295 350 395 Speed reference value (mm / min) ＋93.5 ＋166.3 ＋200.4 ＋213.8 ＋200.4 ＋166.3 ＋93.5 ＋9.7 Depth (mm) 405 450 505 615 652 695 750 795 Speed reference value (mm / min) -6.5 -57.8 -102.2 -131.3 -123.1 -102.2 -57.8 -6.5

[0075] Appendix 4 Flow rate of the glass liquid at the position of half of the longitudinal centerline length of the cooling section

[0076] Depth (mm) 50 105 148 185 252 295 350 395 Speed (mm / min) ＋93.5 ＋166.3 ＋200.4 ＋213.8 ＋200.4 ＋166.3 ＋93.5 ＋9.7 Depth (mm) 405 450 505 615 652 695 750 795 Speed (mm / min) -7.1 -62 -108 -141 -133 -107 -61 -7.2

[0077] It is found by comparing the measured flow rate of the glass liquid with the reference standard that: at the position half of the longitudinal center line length of the cooling section, the reflux speed of the glass liquid (i.e., the negative flow rate) shows an obvious increasing tendency. If not dealt with in time, it will lead to a change in the state of the glass liquid flow layer in the entire cooling section, easily bringing the glass liquid in the immobile layer at the bottom into the flowing layer, reducing the homogenization quality of the glass liquid, and entering the forming section, affecting the quality of the glass. By increasing the dilution air intensity in the cooling section and reducing the cooling intensity of the water pocket in the cold zone of the cooling section, the flow speed of the glass liquid returns to the reference standard, avoiding the generation of glass defects.

[0078] Example 3

[0079] Select a position on the longitudinal center line 500 mm away from the flow channel at the end of the cooling section of the melting furnace and install a high-temperature flow rate detection device to determine the operation reference standard of the glass liquid at this position. By examining the output and quality of the glass, select multiple dates with relatively high glass output and quality and stable production (i.e., excellent production dates), detect the flow condition of the glass liquid at this position, and take the average value as the operation reference standard of the glass liquid at this position.

[0080] First step: Select 10 excellent production dates, collect the flow direction and flow rate of the glass liquid as the reference standard. When collecting daily, start from 5 mm below the glass liquid surface and gradually adjust the depth of the detection probe inserted into the glass liquid surface downward. Record the depth of the probe from the glass liquid surface and the corresponding flow rate and flow direction of the glass every time a certain depth is inserted. Record the direction of the glass liquid flowing towards the end of the production line (i.e., the production flow) as positive, and record the direction of the glass liquid flowing towards the kiln head of the production line (i.e., the reflux) as negative. Take the average value of the flow rate values at the same depth in 10 days as the standard reference data at the position on the longitudinal center line 500 mm away from the flow channel at the end of the cooling section.

[0081] Second step: During actual production, detect the flow condition of the glass liquid on time every day, obtain the actual flow direction and actual flow rate of the glass liquid, compare the actual measurement data with the standard reference values, and judge whether the flow direction and flow rate of the glass liquid at the measurement position and the change trend of both are consistent with the standard reference data according to the comparison result; if they are consistent, maintain the current flow direction and flow rate of the glass liquid; if they are inconsistent, adjust the corresponding process parameters to make the actual flow direction and actual flow rate of the glass liquid consistent with the standard reference data.

[0082] Table 5 shows the standard reference data at the position on the longitudinal center line 500 mm away from the flow channel at the end of the cooling section of one float glass production line. Table 6 shows the measurement results of the actual flow direction and actual flow rate during a production fluctuation.

[0083] Table 5 Reference standard for the flow rate of the glass liquid at the end of the cooling section near the flow channel

[0084] Depth (mm) 10 25 85 150 190 250 290 298 Speed reference value (mm / min) ＋237.3 ＋255.8 ＋296.31 ＋279.3 ＋237.3 ＋129.3 ＋27.3 ＋4 Depth (mm) 355 400 498 550 602 650 700 740 Speed reference value (mm / min) -45.5 -81.3 -126.8 -133 -126.8 -110 -81.3 -15

[0085] Table 6 Glass melt flow velocity near the end of the cooling section close to the runner

[0086] Depth (mm) 10 25 85 150 190 250 290 298 Speed (mm / min) ＋231 ＋248 ＋287 ＋270 ＋232 ＋125 ＋26 ＋3.5 Depth (mm) 355 400 498 550 602 650 700 740 Speed (mm / min) -45.5 -81.3 -126.8 -133 -126.8 -110 -81.3 -15

[0087] It is found by comparing the measured flow velocity of the glass melt with the reference standard that there is an obvious decreasing trend in the velocity near the longitudinal center line of the cooling section close to the runner. If not dealt with in time, it will lead to a change in the state of the glass melt flow layer in the entire cooling section, easily bringing the glass melt in the non-moving layer at the bottom into the flowing layer, reducing the homogenization quality of the glass melt, entering the forming section, and at the same time making it difficult to control the flow rate of the glass melt entering the forming section, affecting the output and quality of the glass. By reducing the intensity of the dilution air in the cooling section, the flow velocity of the glass melt returns to the reference standard.

[0088] In addition, those skilled in the art should understand that although there are many problems in the prior art, each embodiment or technical solution of the present invention can be improved only in one or several aspects, and it is not necessary to solve all the technical problems listed in the prior art or the background art at the same time. Those skilled in the art should understand that the content not mentioned in a claim should not be regarded as a limitation to that claim.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Other modifications or equivalent replacements made by those of ordinary skill in the art to the technical solutions of the present invention should be covered within the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for improving the homogenization quality of molten glass, characterized in that: The method includes the following steps: Select measurement positions in the glass melting furnace, which are respectively: near the throat water pocket, at the position of half of the longitudinal center line length of the cooling section, and near the flow port at the end of the cooling section. At the position near the throat water pocket, different depths of the forward flow layer are selected as 400 - 595 mm, and different depths of the return flow layer are selected as 605 - 800 mm. At the position of half of the longitudinal center line length of the cooling section, different depths of the forward flow layer are selected as 50 - 395 mm, and different depths of the return flow layer are selected as 405 - 800 mm. At the position near the flow port at the end of the cooling section, different depths of the forward flow layer are selected as 10 - 300 mm, and different depths of the return flow layer are selected as 355 - 740 mm; Under the condition that the production working conditions are stable and both the glass output and quality are stable, obtain the flow direction and flow velocity of the glass liquid at different depths at the measurement positions in the glass melting furnace as standard reference data; During actual production, measure the actual flow direction and actual flow velocity of the glass liquid at different depths at the measurement positions in the glass melting furnace, and compare them with the standard reference data to determine whether the change trend of the flow direction, flow velocity or both of the glass liquid at the measurement positions is consistent with the standard reference data; if they are consistent, maintain the current flow direction and flow velocity of the glass liquid; if they are not consistent, adjust the corresponding process parameters to make the actual flow direction and actual flow velocity of the glass liquid consistent with the standard reference data.

2. The method for improving the homogenization quality of molten glass according to claim 1, characterized in that: Install a high-temperature flow velocity detection device at the measurement positions to measure the flow velocity of the glass liquid at different depths at the measurement positions.

3. A method for improving the homogenization quality of glass liquid as described in claim 2, characterized in that: The high-temperature flow velocity detection device includes: a high-temperature flow velocity measurement module, a data analysis and processing module, a display module, a cooling and protection module, a lifting module and a power supply module. The high-temperature flow velocity measurement module is connected to the data analysis and processing module, the data analysis and processing module is connected to the display module, the cooling and protection module is arranged outside the data analysis and processing module, the lifting module is connected to the outside of the cooling and protection module, and the power supply module is connected to the power supply ends of the high-temperature flow velocity measurement module, the data analysis and processing module, the display module and the lifting module.

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