A method for controlling oxygen content in different regions of a glass melting furnace, a control system using the method, and a method for melting glass
By obtaining the Redox value and melting kiln oxygen content of the glass compound and calculating and adjusting the oxygen content, the instability problem of redox state control during the glass melting process is solved, and the melting quality and clarification efficiency of glass are improved.
Patent Information
- Application Number
- CN202311269925.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-28
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2043-09-28
AI Technical Summary
During the glass melting process, the prior art is difficult to achieve real redox state control, resulting in unstable quality of the glass melting and failure to fully utilize the effect of the sulfate clarifier.
By obtaining the Redox value of the glass compound and the actual oxygen content in each area of the melting kiln, the uncompensated and compensated oxygen content adjustment value is calculated, and the oxygen content in the combustible oxygen system is used to adjust the oxygen content and accurately control the oxygen content in each area to achieve the goal The oxygen content is achieved.
The precise adjustment of oxygen content in each area has been achieved, the glass melting efficiency and clarification effect have been improved, and the glass melting quality has been improved.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of glass melting furnaces, in particular to a method for controlling oxygen content in different regions of a glass melting furnace, a control system using the method and a glass melting method. Background Art
[0002] In the glass manufacturing process, the clarification process is the key link to obtain uniform, bubble-free, high-quality glass products. This is a complex physical and chemical process. The perfection of the clarification process is related to factors such as the composition of the batch, the melting process system, the composition and pressure of the atmosphere in the kiln, the properties of the gas in the bubbles, and the clarifier used. In the actual glass production process, companies have made great efforts in all aspects above to improve the melting quality, including the design of the melting furnace, COD monitoring of raw materials, melting process, and refined control of atmosphere and pressure.
[0003] Reductive sulfur clarification is to introduce sulfate clarifier (glauber's salt) into the glass raw materials to improve the melting and clarification of the glass. At the same time, some reducing substances (such as carbon powder, graphite, etc.) are introduced to prevent the formation of nitrate water. The clarification principle mainly includes three aspects. At the low temperature stage, the molten sulfate and silicate are immiscible, playing the role of "surfactant" and accelerating the dissolution of solid particles; as the temperature rises, sodium sulfate begins to decompose, and its decomposition product sodium oxide is transmitted to the glass through the interface between the glass melt, playing a unique role of interface turbulence, accelerating the mixing and homogenization of the glass; continue to heat up to the melting temperature of the glass, after the partial pressure of the product SO2 of sodium sulfate reaches a certain level, it carries the existing bubbles in the melt to rise, and at the same time brings the area with more Na2O to the surface of the melt, realizing the homogenization and clarification of the glass. Corresponding to the above principles, we can monitor and control the oxygen content at different stages of the melting process, form a gradient distribution of the atmosphere in the melting furnace, thereby forming a gradient dissolution of sulfate in the melting furnace, giving full play to the role of sulfate at different stages, and achieving the purpose of improving the quality of glass melting.
[0004] The redox state control in the glass melting process, in addition to the redox property of the furnace combustion atmosphere, the redox potential of the batch added to the furnace also affects the uniformity of glass melting. However, the monitoring of batches, melting processes and performance is often fragmented, and production control is more dependent on empirical data. For example, the Redox value of the batch in production is only used as a monitoring indicator, but it has not been truly used in real time. Atmosphere control is also relatively independent, and the impact of the raw materials on the atmosphere is not taken into account to achieve automatic control, resulting in poor control effects. Even the reasons for the large fluctuations in the atmosphere of the melting furnace are unclear, resulting in unstable glass melting quality. Summary of the invention
[0005] In view of this, the technical problem to be solved by the present invention is to provide a method for controlling the oxygen content in different areas of a glass melting furnace, a control system using the method and a glass melting method. The control method provided by the present invention can achieve precise control of the oxygen content in different areas of the melting furnace through the Redox value, thereby giving full play to the role of the sulfate clarifier and improving the melting quality in the glass melting process.
[0006] The present invention provides a method for controlling oxygen content in different regions of a glass melting furnace, comprising the following steps:
[0007] S1) obtaining the Redox value of the glass batch entering the glass melting furnace and the actual oxygen content of each area of the glass melting furnace;
[0008] S2) obtaining an uncompensated oxygen content adjustment value of each region according to the target oxygen content of each region and the actual oxygen content of each region in step S1); and obtaining an oxygen content adjustment compensation value of each region according to the Redox value of the glass batch material in step S1);
[0009] S3) obtaining a compensated oxygen content adjustment value for each region according to the uncompensated oxygen content adjustment value and the oxygen content adjustment compensation value for each region in step S2);
[0010] S4) According to the compensated oxygen content adjustment value of step S3), the actual oxygen content of each area of step S1) is adjusted to the target oxygen content of each area of step S2).
[0011] The inventors of the present application creatively discovered that by obtaining the oxygen content adjustment compensation value of each region through the Redox value of the glass batch, the problem that different batches of glass batch have different degrees of influence on the Redox value and thus the oxygen content cannot be accurately adjusted can be solved, and the actual oxygen content of each region can be accurately adjusted to the target oxygen content, thereby giving full play to the role of the sulfate clarifier and improving the glass melting efficiency.
[0012] The control method of the present invention first obtains the Redox value of the glass batch entering the glass melting furnace and the actual oxygen content of each area of the glass melting furnace. The glass batch of the present invention is a glass batch for melting glass well known to those skilled in the art; the type of glass obtained after melting the glass batch of the present invention is specifically a glass type that can be clarified using the reducing sulfur clarification principle, including but not limited to soda-lime glass, medium aluminum glass or high aluminum glass produced using a float process or a rolling production process. The Redox value of the present invention is used to measure the redox ability of the oxidizing components and reducing components in the glass batch. The actual oxygen content of each area of the glass melting furnace of the present invention is the residual oxygen content in the flue gas after combustion. In certain embodiments of the present invention, the Redox value of the glass batch entering the glass melting furnace is obtained through the glass batch Redox data platform, and the actual oxygen content of each area of the glass melting furnace is obtained through the oxygen monitoring module.
[0013] After obtaining the Redox value of the glass batch entering the glass melting furnace and the actual oxygen content of each area of the glass melting furnace, the present invention obtains the uncompensated oxygen content adjustment value of each area according to the target oxygen content of each area and the actual oxygen content of each area; and obtains the oxygen content adjustment compensation value of each area according to the Redox value of the glass batch.
[0014] The present invention obtains the oxygen content adjustment compensation value of each region according to the Redox value of the glass batch material. Specifically, when the Redox value is greater than 4.5, the oxygen content adjustment compensation value of each region is ≥0; when the Redox value is less than 4.5, the oxygen content adjustment compensation value of each region is ≤0; when the Redox value is equal to 4.5, the oxygen content adjustment compensation value of each region is 0.
[0015] The present invention obtains the uncompensated oxygen content adjustment value of each area according to the target oxygen content of each area and the actual oxygen content of each area. Specifically, the uncompensated oxygen content adjustment value is the difference between the actual oxygen content and the target oxygen content. More specifically, when the actual oxygen content is lower than the target oxygen content of each area, the uncompensated oxygen content adjustment value is >0; when the actual oxygen content is higher than the target oxygen content of each area, the uncompensated oxygen content adjustment value is <0; when the actual oxygen content is equal to the target oxygen content of each area, the uncompensated oxygen content adjustment value is 0.
[0016] After obtaining the uncompensated oxygen content adjustment value and the oxygen content adjustment compensation value of each region, the present invention obtains the compensated oxygen content adjustment value of each region according to the uncompensated oxygen content adjustment value and the oxygen content adjustment compensation value of each region. Specifically, the sum of the uncompensated oxygen content adjustment value and the oxygen content adjustment compensation value of each region is the compensated oxygen content adjustment value of each region.
[0017] After obtaining the compensated oxygen content adjustment value of each region, the present invention adjusts the actual oxygen content of each region to the target oxygen content of each region according to the compensated oxygen content adjustment value. Specifically, when the Redox value is greater than 4.5, if the actual oxygen content of each region is lower than the target oxygen content of each region, the compensated oxygen content adjustment value is greater than 0; if the actual oxygen content of each region is higher than the target oxygen content of each region, the compensated oxygen content adjustment value is less than or equal to 0; when the Redox value is less than 4.5, if the actual oxygen content of each region is lower than the target oxygen content of each region, the compensated oxygen content adjustment value is greater than or equal to 0; if the actual oxygen content of each region is less than or equal to the target oxygen content of each region, the compensated oxygen content adjustment value is greater than or equal to 0; If the actual oxygen content of each region is higher than the target oxygen content of each region, the compensated oxygen content adjustment value is <0; if the actual oxygen content of each region is equal to the target oxygen content of each region, the compensated oxygen content adjustment value is ≤0; when the Redox value is equal to 4.5, if the actual oxygen content of each region is lower than the target oxygen content of each region, the compensated oxygen content adjustment value is >0; if the actual oxygen content of each region is higher than the target oxygen content of each region, the compensated oxygen content adjustment value is <0; if the actual oxygen content of each region is equal to the target oxygen content of each region, the compensated oxygen content adjustment value is 0.
[0018] In the present invention, if the compensated oxygen content adjustment value is greater than 0, the oxygen content is increased and the combustion oxygen ratio is reduced through the combustion-supporting oxygen system of each area. If the compensated oxygen content adjustment value is less than 0, the oxygen content is reduced and the combustion oxygen ratio is increased through the combustion-supporting oxygen system of each area. If the compensated oxygen content adjustment value is 0, there is no need to adjust the oxygen content.
[0019] The glass melting furnace described in the present invention includes any one of an all-oxygen combustion furnace and an air furnace. The present invention initially starts from the all-oxygen combustion furnace, but in fact the present invention is applicable to both all-oxygen combustion furnaces and air furnaces; the all-oxygen combustion furnace can adjust the fuel-oxygen ratio by increasing or decreasing the amount of oxygen according to the adjusted value of the oxygen content after compensation, while the air furnace can adjust the fuel-oxygen ratio by increasing or decreasing the air ratio. The present invention is different from the prior art that only focuses on the Redox coefficient of the glass batch but does not incorporate it into production control. Even if the prior art monitors the Redox coefficient of the glass batch, it does not really combine it with production; the advantage of the present invention is that the Redox coefficient of the glass batch is incorporated into production control, thereby improving production accuracy and product quality.
[0020] The present invention provides a method for melting glass, comprising: melting glass batch materials and reducing sulfur clarifiers in a glass melting furnace in sequence through a first region, a second region and a third region to obtain glass. Specifically, during the melting process, the actual oxygen content of the first region, the second region and the third region is controlled to be a target oxygen content by using the above control method; the target oxygen content of the first region is 16% to 17%; the target oxygen content of the second region is 8.5% to 9%; the target oxygen content of the third region is 5% to 5.5%.
[0021] The temperature of the first zone of the present invention is 1000℃~1200℃; the temperature of the second zone is 1350℃~1450℃; the temperature of the third zone is 1500℃~1575℃; specifically, the temperature of each zone refers to the temperature of the glass liquid containing glass batch and reducing sulfur clarifier flowing through each zone. The glass batch of the present invention is the same as above and will not be repeated. The reducing sulfur clarifier of the present invention includes sodium sulfate and carbon powder. The content of sodium sulfate of the present invention is 0.5wt%~2.5wt%; the content of carbon powder is 2.5wt%~3.5wt%. The present invention uses a combination of sodium sulfate and carbon powder as a reducing sulfur clarifier, which has the advantage of incorporating the redox coefficient of the glass batch into production control, thereby improving the clarification efficiency of the clarifier in the process of melting glass in the melting furnace.
[0022] The present invention also provides a glass melting furnace regional atmosphere control system applying the above-mentioned control method, comprising an oxygen monitoring module, a glass batch Redox data platform and an atmosphere calculation and control system; wherein the oxygen monitoring module is used to obtain the actual oxygen content of each area of the glass melting furnace; the glass batch Redox data platform is used to obtain the Redox value of the glass batch entering the glass melting furnace; the atmosphere calculation and control system is used to obtain the oxygen content adjustment compensation value, uncompensated oxygen content adjustment value and compensated oxygen content adjustment value of each area, and is used to adjust the actual oxygen content of each area to the target oxygen content of each area.
[0023] The present invention provides a method for controlling the oxygen content of a glass melting furnace by region, a control system using the method, and a method for melting glass. The control method provided by the present invention is a method for accurately controlling the oxygen content of a melting furnace by region according to the Redox value, that is, by associating the Redox data platform system of the glass batch with the monitoring system of the oxygen content in different regions of the melting furnace, the actual oxygen content of each region is adjusted to the target oxygen content, thereby giving full play to the role of the sulfate clarifier and improving the melting quality in the glass melting process. Experiments show that the control method provided by the present invention successfully adjusts the oxygen content of each region to the target oxygen content, and the substantial reduction in the number of bubbles monitored online confirms that the clarifier plays a more full role, thereby improving the melting quality of the glass. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 This is a schematic diagram of the oxygen monitoring module for each zone of the melting furnace;
[0025] Figure 2 Schematic diagram of the furnace zone atmosphere control system. DETAILED DESCRIPTION
[0026] The present invention discloses a method for controlling the oxygen content of a glass melting furnace by region, a control system using the method, and a method for melting glass. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters for implementation. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all deemed to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.
[0027] The glass melting furnace of the present invention is divided into a melting furnace space area No. 1, a melting furnace space area No. 2 and a melting furnace space area No. 3, wherein the glass liquid temperature corresponding to the melting furnace space area No. 1 is 1000-1200°C; the glass liquid temperature corresponding to the melting furnace space area No. 2 is 1350-1450°C; and the glass liquid temperature corresponding to the melting furnace space area No. 3 is 1500-1575°C. The oxygen content in the glass melting furnace of the present invention is detected by the melting furnace regional oxygen detection module, such as Figure 1 As shown, Figure 1 This is a schematic diagram of the oxygen monitoring module for each zone of the melting furnace. Figure 1 1, 2 and 3 respectively represent melting furnace space area No. 1, melting furnace space area No. 2 and melting furnace space area No. 3, and 4, 5 and 6 respectively represent zirconia oxygen sensors corresponding to the three areas No. 1 to 3, which are used to measure the oxygen content of the melting furnace spaces in the three areas No. 1, No. 2 and No. 3 respectively. The oxygen content is measured by detecting the residual oxygen content in the flue gas in the three areas No. 1 to 3.
[0028] In the glass melting process, the oxygen content in different areas of the melting furnace is monitored, and the value changes of the glass batch Redox data platform are used to control the atmosphere of the melting furnace in different areas; Figure 2 As shown, Figure 2 This is a schematic diagram of the furnace zone atmosphere control system. The control method is as follows:
[0029] Set the oxygen content in the flue gas of target area 1 to be between 16% and 17%, the oxygen content in the flue gas of area 2 to be between 8.5% and 9%, and the oxygen content in the flue gas of area 3 to be between 5% and 5.5%. Compare the actual monitoring value of oxygen content in each area with the target value. If the actual oxygen content in the corresponding area is lower than the target value and Redox>4.5, it is necessary to slowly increase the oxygen content and reduce the oxygen ratio through the combustion-supporting oxygen control system of each area until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is higher than the target value and its Redox coefficient is <4.5, it is necessary to slowly reduce the oxygen content and increase the oxygen ratio through the combustion-supporting oxygen control system of each area until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is lower than the target value and Redox<4.5, it is necessary to slowly increase the oxygen content and reduce the oxygen ratio through the combustion-supporting oxygen control system of each area until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is higher than the target value, and Redox>4.5, it is necessary to slowly reduce the oxygen content and increase the oxygen ratio through the combustion-supporting oxygen control system of each area until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is equal to the target value, and Redox>4.5, it is necessary to slowly increase the oxygen content and reduce the oxygen ratio through the combustion-supporting oxygen control system of each area, or do not adjust the oxygen content until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is equal to the target value, and Redox<4.5, it is necessary to reduce the oxygen content and increase the oxygen ratio through the combustion-supporting oxygen control system of each area, or do not adjust the oxygen content until the oxygen content in the flue gas of each area reaches the control target. If the actual oxygen content in the corresponding area is equal to the target value, and Redox=4.5, no adjustment is made. Redox ensures that it is compared with the target value through the atmosphere calculation and control system of different areas, the difference compensation, and then the atmosphere of the melting furnace is controlled by area, giving full play to the role of sulfate clarifier and improving glass melting efficiency.
[0030] The present invention will be further described below in conjunction with embodiments:
[0031] Examples 1 to 10
[0032] A soda-lime glass batch with a sodium sulfate content of 1.5% and a carbon powder content of 3.5% was melted in the above-mentioned glass melting furnace. Under stable production conditions, the Redox value fluctuated and the oxygen content in different areas fluctuated. The oxygen content was adjusted according to the above-mentioned control method and bubbles were monitored online.
[0033] Comparative Example 1
[0034] A soda-lime glass batch with a sodium sulfate content of 1.5% and a carbon powder content of 3.5% was melted in the above glass melting furnace. Under stable production conditions, the Redox value fluctuated, the oxygen content in different areas fluctuated, no oxygen content compensation was performed, and bubbles were monitored online.
[0035] The adjustment results of Examples 1 to 10 and Comparative Example 1 are shown in Table 1:
[0036] Table 1
[0037]
[0038]
[0039] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.
Claims
1. A method for controlling oxygen content in different regions of a glass melting furnace, characterized in that: The following steps are involved: S1) obtaining the Redox value of the glass batch entering the glass melting furnace and the actual oxygen content of each area of the glass melting furnace; S2) obtaining an uncompensated oxygen content adjustment value for each region according to the target oxygen content of each region and the actual oxygen content of each region in step S1); and obtaining the oxygen content adjustment compensation value of each region according to the Redox value of the glass batch material in step S1); S3) obtaining a compensated oxygen content adjustment value for each region according to the uncompensated oxygen content adjustment value and the oxygen content adjustment compensation value for each region in step S2); S4) According to the compensated oxygen content adjustment value of step S3), the actual oxygen content of each area of step S1) is adjusted to the target oxygen content of each area of step S2).
2. The control method according to claim 1, characterized in that: In step S2), when the Redox value is greater than 4.5, the oxygen content adjustment compensation value is ≥ 0; When the Redox value is less than 4.5, the oxygen content adjustment compensation value is ≤0; When the Redox value is equal to 4.5, the oxygen content adjustment compensation value is 0.
3. The control method according to claim 1, characterized in that: In step S2), when the actual oxygen content is lower than the target oxygen content of each area, the uncompensated oxygen content adjustment value is greater than 0; When the actual oxygen content is higher than the target oxygen content of each zone, the uncompensated oxygen content adjustment value is less than 0; When the actual oxygen content is equal to the target oxygen content of each zone, the uncompensated oxygen content adjustment value is 0.
4. The control method according to any one of claims 1 to 3, characterized in that: In step S3), when the Redox value is greater than 4.5, if the actual oxygen content of each region is lower than the target oxygen content of each region, the compensated oxygen content adjustment value is>0; if the actual oxygen content of each region is higher than the target oxygen content of each region, the compensated oxygen content adjustment value is≤0; if the actual oxygen content of each region is equal to the target oxygen content of each region, the compensated oxygen content adjustment value is≥0; When the Redox value is less than 4.5, if the actual oxygen content of each region is lower than the target oxygen content of each region, the compensated oxygen content adjustment value is ≥0; if the actual oxygen content of each region is higher than the target oxygen content of each region, the compensated oxygen content adjustment value is <0; if the actual oxygen content of each region is equal to the target oxygen content of each region, the compensated oxygen content adjustment value is ≤0; When the Redox value is equal to 4.5, if the actual oxygen content of each area is lower than the target oxygen content of each area, the compensated oxygen content adjustment value is greater than 0; if the actual oxygen content of each area is higher than the target oxygen content of each area, the compensated oxygen content adjustment value is less than 0; if the actual oxygen content of each area is equal to the target oxygen content of each area, the compensated oxygen content adjustment value is 0.
5. A method for melting glass, characterized in that: include: The glass batch material and the reducing sulfur clarifier are sequentially melted in a first zone, a second zone and a third zone in a glass melting furnace to obtain glass; During the melting process, the actual oxygen contents in the first region, the second region and the third region are controlled to be the target oxygen contents by using the control method described in any one of claims 1 to 4.
6. The melting method according to claim 5, characterized in that: The target oxygen content of the first zone is 16% to 17%; The target oxygen content of the second zone is 8.5% to 9%; The target oxygen content of the third zone is 5% to 5.5%.
7. The melting method according to claim 5, characterized in that: The temperature of the first region is 1000-1200°C; The temperature of the second zone is 1350°C to 1450°C; The temperature of the third zone is 1500°C to 1575°C.
8. The melting method according to claim 5, characterized in that: The reducing sulfur clarifier includes sodium sulfate and carbon powder.
9. The melting method according to claim 8, characterized in that: The content of the sodium sulfate is 0.5wt% to 2.5wt%; The content of the carbon powder is 2.5wt% to 3.5wt%.
10. A glass melting furnace regional atmosphere control system using the control method described in any one of claims 1 to 4, comprising an oxygen monitoring module, a glass batch Redox data platform and an atmosphere calculation and control system.