A device and method for controlling environmental parameters of the tin bath in float glass production.

Abstract

This invention relates to a control device and method for environmental parameters of the tin bath in float glass production, belonging to the field of float glass production quality control technology. The device includes: pressure sensors and oxygen content analyzers installed in different temperature zones of the tin bath; a main protective gas pipeline connected to the tin bath via branches; the main protective gas pipeline having at least six branches; the main protective gas pipeline being equipped with flow meters, temperature sensors, and constant temperature control equipment; each branch being equipped with flow meters, temperature sensors, and constant temperature control equipment; and the tin bath being equipped with dew point monitoring equipment and electrically controlled flow control valves. The control device provided by this invention can achieve closed-loop control of six core parameters: tin bath pressure, protective gas flow rate, molten tin oxygen content, internal dew point, protective gas temperature, and the opening degree of the electrically controlled flow control valves, thereby improving control accuracy and product quality. Simultaneously, the system has high reliability and economic benefits.

Description

Technical Field

[0001] This invention relates to the field of float glass production quality control technology, specifically to a control device and method for controlling environmental parameters of the tin bath in float glass production, and more particularly to an intelligent control device and method for purifying the tin bath environment in float glass production. Background Technology

[0002] In float glass production, the stability of the internal environmental parameters of the tin bath directly affects the glass surface quality and yield.

[0003] For example, CN121735535A discloses an intelligent control system and method for the protective gas flow direction of a float glass tin bath. The system includes a sensing system, a central control system, and an execution system. The central control system is connected to the sensing system and the execution system respectively. The sensing system includes multiple sets of laser sheet light sources, a high-definition industrial camera, and a data acquisition module. The data acquisition module can generate airflow direction and velocity cloud maps through the PIV principle. The sensing system can communicate with the DCS system to obtain process parameters. The central control system includes an industrial computer and an AI intelligent control model. The AI ​​intelligent control model has a deep reinforcement learning algorithm. The execution system includes at least two sets of adjustable air curtain generators. This system realizes an intelligent control system and modulation method for the protective gas flow direction of a float glass tin bath based on a simple multi-level adjustable air curtain. It is adaptable to abnormal working conditions of the tin bath and can effectively stabilize the protective gas flow direction.

[0004] CN109081558A discloses an optimization control method for the float glass forming process, relating to the glass production field; the method includes pre-setting three standard parameter optimization libraries based on general operating condition data: forming temperature curve optimization library, protective gas optimization library, and edge-pulling machine optimization library; when a new operating condition occurs during the production process, the new operating condition data is searched in the corresponding standard parameter optimization library, and the data most similar to it is matched for the current float glass forming process.

[0005] However, the following technical challenges still exist in the current technology for controlling the solder bath environment:

[0006] ① The pressure inside the tin bath is prone to fluctuation due to external interference, and traditional single-loop control is difficult to achieve stable control within ±0.5Pa;

[0007] ② Uneven distribution of protective gas flow leads to excessive oxygen content in local areas, and the existing control method lacks precise coordinated regulation of the flow of each branch;

[0008] ③ There is a strong coupling relationship between the oxygen content of molten tin and the dew point temperature in the bath, and traditional control methods are difficult to achieve synergistic optimization between the two; the coverage of key parameter monitoring points is insufficient, and it is impossible to establish a complete environmental status perception system for the tin bath.

[0009] In summary, the float glass manufacturing process still suffers from problems such as insufficient precision in controlling the environmental parameters of the tin bath and poor control performance due to strong coupling of multiple parameters. Summary of the Invention

[0010] In view of the problems existing in the prior art, the purpose of the present invention is to provide a control device and control method for the environmental parameters of the tin bath in float glass, so as to solve the problems of insufficient control accuracy of the tin bath environmental parameters and poor control effect caused by strong coupling of multiple parameters.

[0011] To achieve this objective, the present invention adopts the following technical solution:

[0012] In a first aspect, the present invention provides a control device for environmental parameters of a tin bath in float glass production, the control device comprising:

[0013] Pressure sensors and oxygen content analyzers are installed in different temperature zones of the tin bath;

[0014] The main protective gas pipeline is configured in the tin bath;

[0015] The main protective gas pipeline is equipped with at least 6 branches;

[0016] The main protective gas pipeline is connected to the tin bath via a branch line;

[0017] The main protective gas pipeline is equipped with a first flow meter, a first temperature sensor, a first control valve, and a first constant temperature control device.

[0018] Each branch is equipped with a second flow meter, a second temperature sensor, a second control valve, and a second constant temperature control device;

[0019] The tin bath is equipped with at least four dew point monitoring devices;

[0020] The tin bath is equipped with at least one electrically controlled flow guide valve;

[0021] The pressure sensor, first flow meter, first temperature sensor, second flow meter, second temperature sensor, first constant temperature control device, second constant temperature control device, oxygen content analyzer, dew point monitoring device, and electrically controlled flow guide valve are all connected to the control unit.

[0022] The control device provided by this invention can achieve closed-loop regulation of six core parameters: solder bath pressure, protective gas flow rate, molten solder oxygen content, internal dew point, protective gas temperature, and the opening degree of the electrically controlled flow guide valve, thereby improving control accuracy and product quality. At the same time, the system has high reliability and economic benefits.

[0023] As a preferred embodiment of the present invention, the different temperature zones include: a high temperature zone, a medium temperature zone, and a low temperature zone, wherein the temperature of the high temperature zone is greater than the temperature of the medium temperature zone and the temperature of the low temperature zone.

[0024] Preferably, the temperature of the high-temperature zone is 900-1100℃.

[0025] Preferably, the temperature in the intermediate temperature zone is 750-850℃.

[0026] Preferably, the temperature of the low-temperature zone is 620-680℃.

[0027] As a preferred technical solution of the present invention, the pressure sensor is set at 1 / 4, 1 / 2 and 3 / 4 of the length of the tank, with the tank length as the reference.

[0028] As a preferred technical solution of the present invention, the main protective gas pipeline and the branch pipeline are connected by a multi-channel gas distribution valve.

[0029] Preferably, the multi-channel gas distribution valve is connected to the control unit.

[0030] As a preferred embodiment of the present invention, the dew point monitoring device is installed at the pressure measurement location in the medium-temperature zone and low-temperature zone of the tin bath.

[0031] Secondly, the present invention provides a method for controlling environmental parameters of the tin bath in float glass production, the control method comprising:

[0032] The current density of the protective gas is collected. If the current density does not match the preset density, the protective gas flow rate is controlled to the standard flow rate based on the gas temperature-flow compensation model; otherwise, it is maintained.

[0033] The current pressure of the solder bath is collected. If the deviation of the current pressure from the preset pressure is greater than the preset deviation, then based on the pressure deviation e... p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model controls the solder bath pressure, and vice versa;

[0034] The current oxygen content of the tin bath is collected. If the current oxygen content does not match the preset oxygen content, the oxygen content and dew point are controlled synchronously based on the oxygen content-dew point decoupled control model.

[0035] As a preferred technical solution of the present invention, the preset density includes: the density of the gas currently in use at a set operating temperature.

[0036] Preferably, the preset deviation is -10Pa to +5Pa.

[0037] Preferably, the preset oxygen content is ≤5ppm.

[0038] As a preferred technical solution of the present invention, the gas temperature-flow compensation model includes:

[0039] Q n =Q w ×(P w / P n )×(T n / T w );

[0040] In the formula, Q n For standard flow rate, Nm 3 / h;Q w For actual flow rate, Nm 3 / h;P w The absolute pressure under operating conditions is expressed in Pa; P n For standard pressure, 101325 Pa, T w T represents the absolute temperature under operating conditions. w =t + 273.15K, where t is in degrees Celsius; T n The standard temperature is 273.15K.

[0041] As a preferred technical solution of the present invention, the pressure deviation e p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model includes:

[0042] ;

[0043] In the formula, K p K i K d These are parameters that are adjusted in real time based on pressure deviation and rate of change.

[0044] As a preferred technical solution of the present invention, the oxygen content-dew point decoupling control model includes:

[0045] ;

[0046] In the formula, ΔO2 is the oxygen content, ppm; ΔDP is the dew point, °C; Q i For branch gas flow rate, i≥6, Nm 3 / h; Tg is the temperature of the protective gas, K; RH is the relative humidity, %RH.

[0047] Preferably, the control method further includes: collecting the current dew point of the tin bath; if the current dew point does not match the preset dew point, adjusting the protective gas flow rate and the opening of the electrically controlled flow guide valve.

[0048] Preferably, the preset dew point is selected from -45℃ to -40℃.

[0049] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0050] (1) Significantly improved control precision: the pressure fluctuation range of the tin bath is controlled within ±0.5Pa, the stability of the protective gas flow rate reaches more than 98%, and the oxygen content of the tin liquid is stable at ≤5ppm;

[0051] (2) Significant improvement in product quality: reduced the probability of tin defects, improved the smoothness of glass surface, and improved haze index.

[0052] (3) Outstanding economic benefits: Saves 8-12% of protective gas costs and reduces molten tin pollution and waste loss by about RMB 1.2 million per year.

[0053] (4) High system reliability: It can achieve dual-mode redundancy of traditional control and intelligent control, with an average fault-free operating time of ≥8000h. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of a control device for environmental parameters of the tin bath in float glass provided in an embodiment of the present invention;

[0055] Figure 2 This is a diagram showing the calculation of the total protective gas standard flow rate in the oxygen content-dew point decoupling control model logic control of the control method for tin bath environmental parameters in float glass provided by this invention.

[0056] Figure 3 This is an abnormality determination diagram of the protective gas branch in the oxygen content-dew point decoupling control model logic control of the control method for tin bath environmental parameters in float glass provided by the embodiments of the present invention;

[0057] Figure 4 This is a diagram showing the calculation of the protective gas branch flow deviation in the oxygen content-dew point decoupling control model logic control of the control method for tin bath environmental parameters in float glass provided by this invention embodiment;

[0058] Figure 5 This is a calculation diagram of the protective gas flow rate setting in the oxygen content-dew point decoupling control model logic control of the control method for tin bath environmental parameters in float glass provided by the embodiments of the present invention;

[0059] Figure 6 This is a diagram showing the oxygen content-protective gas flow rate control in the oxygen content-dew point decoupling control model logic control method for controlling environmental parameters of the tin bath in float glass provided in this embodiment of the invention.

[0060] In the diagram: 100-tin bath, 110-pressure sensor, 120-oxygen content analyzer, 130-dew point monitoring device, 140-electrically controlled flow guide valve, 200-main protective gas pipeline, 210-branch line, 211-second flow meter, 212-second constant temperature control device, 220-first flow meter, 230-first constant temperature control device, 240-multi-channel gas distribution valve.

[0061] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0062] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0063] In float glass production, the stability of the internal environmental parameters of the tin bath directly affects the glass surface quality and yield. However, existing technologies still face the following technical challenges in tin bath environmental control: ① The internal pressure of the tin bath is prone to fluctuations due to external interference, making it difficult for traditional single-loop control to achieve stable control within ±0.5Pa; ② Uneven distribution of protective gas flow leads to excessive oxygen content in local areas, and existing control methods lack precise coordinated regulation of the flow of each branch; ③ There is a strong coupling relationship between the oxygen content of the molten tin and the dew point temperature inside the bath, making it difficult for traditional control methods to achieve coordinated optimization of the two; Insufficient coverage of key parameter monitoring points prevents the establishment of a complete tin bath environmental status perception system. Based on this, this invention optimizes the relevant control and monitoring system, enabling the control device to achieve closed-loop regulation of six core parameters: tin bath pressure, protective gas flow, molten tin oxygen content, internal dew point, protective gas temperature, and the opening degree of the electrically controlled flow guide valve. This improves control accuracy and product quality, while also offering high reliability and economic benefits, as detailed below:

[0064] I. This embodiment provides a device for controlling environmental parameters of the tin bath in float glass production. An exemplary structure is as follows: Figure 1 As shown, the control device includes:

[0065] Pressure sensors 110 and oxygen content analyzers 120 are installed in different temperature zones of the tin bath 100;

[0066] The protective gas main pipeline 200 is configured in the tin bath 100;

[0067] The main protective gas pipeline 200 is equipped with at least 6 branches 210;

[0068] The main protective gas pipeline 200 is connected to the tin bath 100 via a branch 210;

[0069] The main protective gas pipeline 200 is equipped with a first flowmeter 220, a first temperature sensor, a first control valve, and a first constant temperature control device 230;

[0070] Each branch 210 is equipped with a second flowmeter 211, a second temperature sensor, a second control valve, and a second constant temperature control device 212;

[0071] The tin bath 100 is equipped with at least 4 dew point monitoring devices 130;

[0072] The tin bath 100 is equipped with at least 1 electrically controlled diversion valve 140;

[0073] The pressure sensor 110, the first flowmeter 220, the first temperature sensor, the second flowmeter 211, the second temperature sensor, the first constant temperature control device 230, the second constant temperature control device 212, the oxygen content analyzer 120, the dew point monitoring device 130, and the electrically controlled diversion valve 140 are all connected to the control unit.

[0074] In the present invention, the pressure sensor 110 and the oxygen content analyzer 120 are generally in the high temperature zone (3 bays), the medium temperature zone (11 bays), the low temperature zone (19 bays), etc. The specific positions are determined according to the length of different tin baths 100. Specifically, one or at least two pressure sensors 110 and oxygen content analyzers 120 can be independently set in each temperature zone. Setting multiple ones is more conducive to the accuracy of pressure and oxygen content monitoring, thereby improving the control accuracy. Among them, when multiple oxygen content analyzers 120 are set, they can be set in the depth direction of different temperature zones to more accurately monitor the temperature.

[0075] In the present invention, the pressure sensor 110 and the oxygen content analyzer 120 are specifically set in different temperature zones according to the temperature points of the temperature zones. The specific design positions are based on the corresponding temperature points in the actually selected temperature zones, as long as it can ensure the monitoring of relevant parameters in the corresponding temperature zones.

[0076] In the present invention, the high temperature zone, the medium temperature zone, and the low temperature zone refer to the temperature zones formed along the glass flow direction in the tin bath 100.

[0077] In the present invention, "bay" is a professional term in this field, indicating a section or span.

[0078] In the present invention, the flowmeter can specifically be selected as a volume flowmeter, a mass flowmeter, etc., which are commonly used flowmeters in this field, and are specifically selected reasonably according to actual needs.

[0079] In the present invention, the dew point monitoring device 130 can select devices such as a dew point meter to monitor the dew point of the tin bath 100, and the specific device is reasonably selected according to actual needs.

[0080] The different temperature zones include: a high temperature zone, a medium temperature zone, and a low temperature zone, wherein the temperature of the high temperature zone is greater than the temperature of the medium temperature zone, and the temperature of the low temperature zone is greater than the temperature of the low temperature zone.

[0081] The high-temperature zone refers to the molten tin zone with a temperature of 900-1100℃.

[0082] The medium-temperature zone refers to the area of ​​molten tin with a temperature of 750-850℃.

[0083] The low-temperature zone refers to the molten tin zone with a temperature of 620-680℃.

[0084] The pressure sensor 110 is positioned at 1 / 4, 1 / 2, and 3 / 4 of the tank length, with the tank length as the reference. It can be configured along the direction of glass flow.

[0085] In this invention, when multiple electrically controlled flow guide valves 140 are configured, the electrically controlled flow guide valves 140 are configured at different positions of the solder bath 100, thereby enabling individual control of the pressure at different positions of the solder bath 100, and further improving the control accuracy of the pressure of the solder bath 100.

[0086] In this invention, the configuration position of the electrically controlled flow guide valve 140 can be reasonably configured according to the conventional requirements in the art to ensure that the pressure of the solder bath 100 can be controlled.

[0087] The main protective gas pipeline 200 and the branch pipeline 210 are connected by a multi-channel gas distribution valve 240.

[0088] In this invention, the multi-channel gas distribution valve 240 can be designed by the user using multiple valves and pipelines according to actual needs, or commercially available products that meet the requirements can be purchased.

[0089] The multi-channel gas distribution valve 240 is connected to the control unit.

[0090] The dew point monitoring device 130 is located at the pressure measurement position in the medium temperature zone and low temperature zone of the tin bath 100.

[0091] In this invention, the control unit can be selected as a PID controller or an industrial computer or other commonly used logic controllers in the field.

[0092] In this invention, the specific control process of the control device for the environmental parameters of the tin bath in float glass can be rationally designed according to specific control needs and product requirements, or it can be controlled by the control method for the environmental parameters of the tin bath in float glass provided by this invention. The control method for the environmental parameters of the tin bath in float glass is preferred, which also achieves a good match between the device and the control, ensuring that the production of float glass can be carried out efficiently and with high quality.

[0093] II. This embodiment provides a method for controlling environmental parameters of the tin bath in float glass production, the control method comprising:

[0094] The current density of the protective gas is collected. If the current density does not match the preset density, the protective gas flow rate is controlled to the standard flow rate based on the gas temperature-flow compensation model; otherwise, it is maintained.

[0095] The current pressure of the solder bath is collected. If the deviation of the current pressure from the preset pressure is greater than the preset deviation, then based on the pressure deviation e... p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model controls the solder bath pressure, and vice versa;

[0096] The current oxygen content of the tin bath is collected. If the current oxygen content does not match the preset oxygen content, the oxygen content and dew point are controlled synchronously based on the oxygen content-dew point decoupled control model.

[0097] In this invention, the flow rate of the protective gas is controlled by relevant flow regulating valves. The flow rate of the branch is controlled first, and then the standard flow rates of each branch are summed to regulate the flow rate of the main protective gas pipeline.

[0098] In this invention, the oxygen content of the solder bath is controlled by controlling the flow rate of the protective gas. For example, when the oxygen content of the solder bath is abnormal, the flow rate of the main pipeline or branch of the protective gas is obtained according to the oxygen content-dew point decoupling control model, and then controlled and adjusted by valves, etc., while ensuring that the dew point meets the requirements.

[0099] The preset density includes the density of the gas currently in use at a set operating temperature.

[0100] The preset deviation is -10Pa to +5Pa, for example, it can be -10Pa, -8Pa, -6Pa, -4Pa, -2Pa, -1Pa, 0Pa, 1Pa, 2Pa, 3Pa, 4Pa or 5Pa, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0101] The preset oxygen content is ≤5ppm; when the oxygen content is ≥8ppm, an emergency alarm will be triggered.

[0102] The gas temperature-flow rate compensation model includes:

[0103] Q n =Q w ×(P w / P n )×(T n / T w );

[0104] In the formula, Qn For standard flow rate, Nm 3 / h;Q w For actual flow rate, Nm 3 / h;P w The absolute pressure under operating conditions is expressed in Pa; P n For standard pressure, 101325 Pa, T w T represents the absolute temperature under operating conditions. w =t + 273.15K, where t is in degrees Celsius; T n The standard temperature is 273.15K.

[0105] Wherein, the pressure deviation e p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model includes:

[0106] ;

[0107] In the formula, K p K i K d These are parameters that are adjusted in real time based on pressure deviation and rate of change.

[0108] The oxygen content-dew point decoupling control model includes:

[0109] ;

[0110] In the formula, ΔO2 is the oxygen content, ppm; ΔDP is the dew point, °C; Q i For branch gas flow rate, i≥6, Nm 3 / h; Tg is the temperature of the protective gas, K; RH is the relative humidity, %RH.

[0111] The control method further includes: collecting the current dew point of the tin bath; if the current dew point does not match the preset dew point, adjusting the protective gas flow rate and the opening of the electrically controlled flow guide valve.

[0112] The preset dew point is selected from -45℃ to -40℃, for example, it can be -45℃, -44℃, -43℃, -42℃, -41℃ or -40℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0113] In this invention, when using an oxygen content-dew point decoupling control model, if an abnormal oxygen content is detected, the flow rate of the corresponding branch can be preferentially adjusted while compensating other branches to maintain dew point stability. Oxygen content is inversely proportional to the flow rate of each protective gas branch, meaning increasing the flow rate decreases the oxygen content. Dew point is also inversely proportional to the flow rate of each protective gas branch, meaning increasing the flow rate decreases the dew point, and has a nonlinear exponential-logarithmic composite function relationship with temperature and relative humidity. The logical control relationship is as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, when the oxygen content in this area does not exceed the oxygen content limit, the protective gas control value is equal to the preset value. When the oxygen content exceeds the oxygen content limit, the protective gas control value is equal to the preset value plus the preset deviation.

[0114] In this invention, if the current dew point does not meet the requirements, the dehumidification program can be started automatically. However, it is preferable to adjust the dew point by adjusting the protective gas flow rate and the opening of the electronically controlled flow guide valve.

[0115] III. To illustrate the control effect of the tin bath environmental parameters provided by the control device and method for float glass environmental parameters of the present invention, the following example is used for explanation:

[0116] Example 1

[0117] This embodiment provides a control device and specific control process for environmental parameters of the tin bath in float glass production, as detailed below:

[0118] 1. Hardware Deployment

[0119] Three sets of pressure sensors are installed at the beginning, middle, and end of the tin bath, with spacing at 1 / 4, 1 / 2, and 3 / 4 of the bath length, respectively. One volumetric flow meter is installed on the main pipeline of the protective gas system, and one flow meter of the same model is installed on each of the six inlet branches. Three oxygen content analyzers are arranged in different temperature zones of the tin bath. Four-point array dew point sensors are installed in the medium-temperature and low-temperature zones on both sides of the bath. Figure 1 As shown;

[0120] Executive agency

[0121] The electrically controlled flow guide valve is an intelligent electric regulating valve (opening control accuracy 0.1%).

[0122] Multi-channel gas distribution valve assembly (independently controls each intake branch);

[0123] Protective gas temperature control system (constant temperature control equipment) (temperature control accuracy ±0.5℃).

[0124] 2. Control parameter settings

[0125] The solder bath pressure setting is selected as 25Pa: adjustable within a deviation range of -10Pa to +5Pa depending on the production process;

[0126] Protective gas flow rate setting: Each branch is allocated according to process requirements, with a total flow rate deviation of ≤2%;

[0127] Oxygen content control target: ≤5ppm, alarm threshold set at 8ppm;

[0128] Dew point setting range: -45℃ to -40℃.

[0129] The control process is as follows:

[0130] The current density of the protective gas is collected. If the current density does not match the preset density, the protective gas flow rate is controlled to the standard flow rate based on the gas temperature-flow compensation model; otherwise, it is maintained.

[0131] The current pressure of the solder bath is collected. If the deviation of the current pressure from the preset pressure is greater than the preset deviation, then based on the pressure deviation e... p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model controls the solder bath pressure, and vice versa;

[0132] The current oxygen content of the tin bath is collected. If the current oxygen content does not match the preset oxygen content, or the current dew point does not match the preset dew point, the oxygen content and dew point are controlled synchronously based on the oxygen content-dew point decoupling control model. Otherwise, they are maintained.

[0133] The current dew point of the tin bath is collected. If the current dew point does not match the preset dew point, the protective gas flow rate and the opening of the electronically controlled flow guide valve are adjusted. Otherwise, the dehumidification program is maintained. If the limit is exceeded, the dehumidification program can be started automatically.

[0134] Comparative Example 1

[0135] The only difference from Example 1 is that when the current density does not match the preset density, the temperature of the protective gas is directly adjusted to match the current density with the preset density, that is, the gas temperature-flow compensation model is not used to control the flow rate of the protective gas.

[0136] Comparative Example 2

[0137] The only difference from Example 1 is that when the deviation between the current pressure and the preset pressure does not match the preset deviation, the flow rate of the protective gas is directly controlled to match the current pressure with the preset pressure, that is, the pressure deviation e is not used. p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model controls the pressure in the solder bath.

[0138] Comparative Example 3

[0139] The only difference from Example 1 is that when the current oxygen content does not match the preset oxygen content, the flow rate of the protective gas is directly controlled to make the current oxygen content match the preset oxygen content, that is, the oxygen content-dew point decoupling control model is not used to synchronously control the oxygen content and dew point.

[0140] The performance indicators of the resulting glass products are detailed in Table 1 below, obtained by using the control process described above for float glass production.

[0141] Table 1

[0142]

[0143] As shown in Table 1, the solution provided by this invention, through the combined control of protective gas flow rate, solder bath pressure, oxygen content inside the solder bath, dew point inside the solder bath, and electrically controlled flow guide valve, minimizes the uneven distribution and flow fluctuations of the protective gas, maintaining relative stability of the internal pressure of the solder bath, the oxygen content of the molten solder, and the dew point. This improves the glass surface quality, reduces the formation rate of tin defects, and enhances production stability.

[0144] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0145] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0146] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A device for controlling environmental parameters of the tin bath in float glass production, characterized in that, The control device includes: Pressure sensors and oxygen content analyzers are installed in different temperature zones of the tin bath; The main protective gas pipeline is configured in the tin bath; The main protective gas pipeline is equipped with at least 6 branches; The main protective gas pipeline is connected to the tin bath via a branch line; The main protective gas pipeline is equipped with a first flow meter, a first temperature sensor, a first control valve, and a first constant temperature control device. Each branch is equipped with a second flow meter, a second temperature sensor, a second control valve, and a second constant temperature control device; The tin bath is equipped with at least four dew point monitoring devices; The tin bath is equipped with at least one electrically controlled flow guide valve; The pressure sensor, first flow meter, first temperature sensor, second flow meter, second temperature sensor, first constant temperature control device, second constant temperature control device, oxygen content analyzer, dew point monitoring device, and electrically controlled flow guide valve are all connected to the control unit.

2. The control device as described in claim 1, characterized in that, The different temperature zones include: a high temperature zone, a medium temperature zone, and a low temperature zone, wherein the temperature of the high temperature zone is greater than the temperature of the medium temperature zone, which is greater than the temperature of the low temperature zone. Preferably, the temperature of the high-temperature zone is 900-1100℃; Preferably, the temperature in the intermediate temperature zone is 750-850℃; Preferably, the temperature of the low-temperature zone is 620-680℃.

3. The control device as described in claim 1, characterized in that, The pressure sensors are positioned at 1 / 4, 1 / 2, and 3 / 4 of the tank length, based on the tank length.

4. The control device as described in claim 1, characterized in that, The main protective gas pipeline and the branch pipelines are connected by a multi-channel gas distribution valve; Preferably, the multi-channel gas distribution valve is connected to the control unit.

5. The control device as described in claim 3, characterized in that, The dew point monitoring equipment is installed at the pressure measurement locations in the medium and low temperature zones of the tin bath.

6. A method for controlling environmental parameters of the tin bath in float glass production, characterized in that, The control method includes: The current density of the protective gas is collected. If the current density does not match the preset density, the protective gas flow rate is controlled to the standard flow rate based on the gas temperature-flow compensation model; otherwise, it is maintained. The current pressure of the solder bath is collected. If the deviation of the current pressure from the preset pressure is greater than the preset deviation, then based on the pressure deviation e... p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model controls the solder bath pressure, and vice versa; The current oxygen content of the tin bath is collected. If the current oxygen content does not match the preset oxygen content, the oxygen content and dew point are controlled synchronously based on the oxygen content-dew point decoupled control model.

7. The control method as described in claim 6, characterized in that, The preset density includes: the density of the gas currently in use at a set operating temperature; Preferably, the preset deviation is -10Pa to +5Pa; Preferably, the preset oxygen content is ≤5ppm.

8. The control method as described in claim 6, characterized in that, The gas temperature-flow rate compensation model includes: Q n =Q w ×(P w / P n )×(T n / T w ); In the formula, Q n For standard flow rate, Nm 3 / h;Q w For actual flow rate, Nm 3 / h;P w The absolute pressure under operating conditions is expressed in Pa; P n For standard pressure, 101325 Pa, T w T represents the absolute temperature under operating conditions. w =t + 273.15K, where t is in degrees Celsius; T n The standard temperature is 273.15K.

9. The control method as described in claim 6, characterized in that, The pressure deviation e p (t) and the adjustment amount of the opening of the electronically controlled diverter valve The model includes: ； In the formula, K p K i K d These are parameters that are adjusted in real time based on pressure deviation and rate of change.

10. The control method as described in claim 6, characterized in that, The oxygen content-dew point decoupling control model includes: ； In the formula, ΔO2 is the oxygen content, ppm; ΔDP is the dew point, °C; Q i For branch gas flow rate, i≥6, Nm 3 / h; Tg is the temperature of the protective gas, K; RH is the relative humidity, %RH; Preferably, the control method further includes: collecting the current dew point of the tin bath; if the current dew point does not match the preset dew point, adjusting the protective gas flow rate and the opening of the electronically controlled flow guide valve. Preferably, the preset dew point is selected from -45℃ to -40℃.

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