A glass and a method of making the same

Abstract

This invention provides a type of glass and its preparation method, belonging to the field of glass technology. The glass batch comprises the following raw materials in parts by weight: 679-713 parts silica sand, 4-40 parts feldspar, 39-59 parts wollastonite, 129-154 parts dolomite, 42-55 parts limestone, 224-231 parts soda ash, 8-10 parts sodium sulfate, and 0.3-0.4 parts carbon powder. This invention can reduce CO2 emissions from float glass production, decrease bubble defects, and improve the quality of the finished glass.

Description

Technical Field

[0001] This invention belongs to the field of glass technology, and in particular relates to a type of glass and its preparation method. Background Technology

[0002] In the current wave of promoting a low-carbon economy, the green and low-carbon development of the float glass industry is imperative. One of the carbon emission sources in the float glass production process is the decomposition of raw material carbonates. This decomposition refers to the CO2 emissions generated when carbonates such as limestone, dolomite, and soda ash contained in the raw materials used in float glass production decompose at high temperatures.

[0003] Wollastonite is a calcareous metasilicate mineral that can be used in float glass batches. The introduction of wollastonite can effectively reduce the amount of carbonate raw materials used, thereby helping to reduce CO2 emissions during glass production. However, in actual industrial applications, it has been found that the introduction of wollastonite into the glass batch easily leads to an increase in bubble defects in the final glass product, thus affecting glass quality. Summary of the Invention

[0004] This invention provides a glass and its preparation method, aiming to reduce CO2 emissions from float glass, reduce bubble defects, and improve the quality of finished glass.

[0005] In a first aspect, the present invention provides a glass, wherein the glass compound comprises the following raw materials in parts by weight: 679 to 713 parts silica sand, 4 to 40 parts feldspar, 39 to 59 parts wollastonite, 129 to 154 parts dolomite, 42 to 55 parts limestone, 224 to 231 parts soda ash, 8 to 10 parts mirabilite, and 0.3 to 0.4 parts carbon powder.

[0006] In some embodiments, the weight parts of wollastonite are defined as x, and the weight parts of limestone are defined as y, wherein x and y satisfy: 0.46≤x / (x+y)≤0.56.

[0007] In some embodiments, the sodium sulfate content of the glass batch is 2.75% to 2.95%; and / or, the carbon powder content of the glass batch is 2.85% to 3.10%.

[0008] In some embodiments, the wollastonite comprises the following mass fractions: SiO2 49.70%~50.70%, Al2O3 0.73%~0.77%, CaO 42.80%~43.40%, MgO 0.79%~0.83%, and Na2O 0.41%~0.43%.

[0009] In some embodiments, the silica sand comprises the following mass fractions: SiO2 97.04%~98.08%, Al2O3 0.91%~0.98%, CaO 0.01%~0.05%, Na2O 0.46%~0.55%, K2O 0.02%~0.08%, Fe2O3 0.04%~0.08%; and / or, the feldspar comprises the following mass fractions: SiO2 72.10%~73.50%, Al2O3 14.50%~15.50%, CaO 0.20%~0.90%, MgO 0.10%~0.20%, Fe2O3 0.30%~0.37%; and / or, the dolomite comprises the following mass fractions: SiO2 0.01%~0.07%, Al2O3 0.01%~0.15%, CaO 30.34%~32.50%, MgO 21.00%~22.25%, Na2O 0.01%~0.05%, Fe2O3 0.01%~0.06%; and / or, the limestone comprises the following mass fractions: SiO2 0.10%~0.30%, Al2O3 9.10%~11.05%, CaO 52.41%~56.88%, MgO 0.22%~0.54%, Fe2O3 0.01%~0.05%.

[0010] In some embodiments, the number of residual bubbles in the glass after being kept at 1450°C for 2 hours is 2 to 3.

[0011] In some embodiments, the glass is defined as melting to a viscosity of 10 during the cooling process. 4 The temperature at dpa·s is the operating temperature T of the glass. w The T w Satisfies: 1020℃≤T w ≤1022℃.

[0012] Secondly, the present invention provides a method for preparing the glass as described above, comprising the following steps: The following raw materials are provided in parts by weight: 679-713 parts silica sand, 4-40 parts feldspar, 39-59 parts wollastonite, 129-154 parts dolomite, 42-55 parts limestone, 224-231 parts soda ash, 8-10 parts mirabilite, and 0.3-0.4 parts carbon powder; the raw materials are mixed evenly to obtain a glass batch; the batch is melted to obtain molten glass; the molten glass is transported to a tin bath for float glass forming to obtain a solid glass strip; the solid glass strip is annealed to obtain glass.

[0013] In some embodiments, the step of melting the glass batch to obtain molten glass includes: melting the glass batch at 1400℃~1600℃ for 5h~10h; and / or, the step of annealing the solid glass strip to obtain glass includes: annealing the solid glass strip at 500℃~700℃ for 1h~5h.

[0014] In some embodiments, the wollastonite has a particle size of 200 mesh to 400 mesh.

[0015] The beneficial effects of the embodiments of the present invention are as follows: The glass batching material of the present invention includes wollastonite, which can reduce CO2 emissions from float glass.

[0016] This invention, by controlling the weight proportions of each raw material within the aforementioned range, provides an effective amount of initial CO2 bubble nuclei during the heating process of the glass batch. This provides nucleation and attachment sites for the gas (O2) released by the subsequent clarifying agent. O2 diffuses into the existing CO2 bubble nuclei, causing them to expand in volume and increase buoyancy, thereby accelerating their upward movement and discharge. Furthermore, the fluxing advantage of wollastonite is effectively utilized, contributing to the formation of a stable, low-viscosity system and promoting the homogenization of the molten glass, thus improving the clarification effect. Therefore, this invention can reduce bubble defects in finished glass products, thereby improving the quality of the finished glass products. Attached Figure Description

[0017] Figure 1 The images show the results of high-temperature visual observation experiments on glass melt at 1450°C for different times in some embodiments of the present invention. Figure 2 The image shows the results of the high-temperature visual observation experiment of the glass melt in Comparative Example 3, which was kept at 1450℃ for different times. Figure 3 The image shows the results of the high-temperature visual observation experiment of the glass melt in Comparative Example 4, which was kept at 1450℃ for different times. Figure 4 The image shows the results of a high-temperature visual observation experiment of the glass melt in Comparative Example 6, which was kept at 1450℃ for different times. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of the present invention and are not intended to limit the present invention. In the present invention, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0019] Carbon emissions during float glass production include the decomposition of carbonates in raw materials. Common carbonate-containing raw materials include limestone, dolomite, and soda ash, which decompose at high temperatures, generating CO2 emissions. Wollastonite, a calcareous metasilicate mineral, can be used in float glass batches. The introduction of wollastonite can effectively reduce the amount of carbonate raw materials used, thus helping to reduce CO2 emissions during glass production. However, the inventors discovered that the introduction of wollastonite increases the number of air bubbles in the finished glass, thereby affecting the quality of the finished glass.

[0020] Therefore, the present invention provides a glass, the glass compound comprising the following raw materials in parts by weight: 679-713 parts silica sand, 4-40 parts feldspar, 39-59 parts wollastonite, 129-154 parts dolomite, 42-55 parts limestone, 224-231 parts soda ash, 8-10 parts mirabilite, and 0.3-0.4 parts carbon powder.

[0021] Silica sand is a type of quartz sand with silicon dioxide (SiO2) as its main component. It is mainly used to introduce SiO2 and K2O. Its weight parts can be any value between 679 parts and 713 parts. For example, the weight parts of silica sand can be 679 parts, 683 parts, 685 parts, 690 parts, 695 parts, 700 parts, 705 parts, 710 parts or 713 parts. If the weight parts of silica sand are too low, the chemical stability and mechanical strength of the glass will decrease. If the weight parts of silica sand are too high, the melting temperature will be too high.

[0022] Feldspar is mainly used to introduce Al2O3, and its weight can be any value between 4 and 40 parts. For example, the weight of feldspar can be 4, 6, 8, 10, 12, 15, 18, 20, 23, 25, 28, 30, 33, 35, 38, or 40 parts. If the weight of feldspar is too low, it will lead to a decrease in the chemical stability and mechanical strength of the glass; if the weight of feldspar is too high, it will increase the melting temperature of the glass.

[0023] The main component of limestone is CaCO3, primarily used to introduce CaO. Furthermore, when heated, limestone decomposes at around 900℃, releasing a large amount of CO2 gas. This CO2 gas, combined with other carbonate raw materials, can form numerous small initial microbubbles in the molten glass. These microbubbles provide nucleation and attachment sites for the gas released by subsequent clarifying agents, acting as "bubble nuclei." The weight percentage of limestone can be any value between 42 and 55 parts; for example, the weight percentages of limestone can be 42, 45, 47, 50, 53, or 55 parts.

[0024] Wollastonite's main component is CaSiO3, primarily used to introduce SiO2 and CaO. Wollastonite can reduce the endothermic process of limestone decomposition, helping to lower the high-temperature melting temperature and viscosity of glass. Furthermore, wollastonite directly introduces SiO2 and CaO through decomposition without releasing additional gases. The weight parts of wollastonite can be any value between 39 and 59 parts; for example, the weight parts of wollastonite can be 39, 43, 45, 48, 50, 52, 55, or 59 parts.

[0025] Dolomite, with the chemical formula CaMg(CO3)2, is mainly used to introduce MgO and CaO. Its weight percentage can be any value between 129 and 154 parts. For example, the weight percentage of dolomite can be 129, 130, 133, 135, 138, 140, 145, 150, or 154 parts. Too low a weight percentage of dolomite will lead to an increase in the high-temperature viscosity of the glass, while too high a weight percentage will reduce the thermal and chemical stability of the glass and increase its brittleness.

[0026] The main component of soda ash is Na₂CO₃, and its main function is to flux and introduce Na₂O. Its weight percentage can be any value between 224 and 241 parts. For example, the weight percentage of soda ash can be 224, 226, 228, 230, 233, 235, 238, or 241 parts. If the weight percentage of soda ash is too low, the melting temperature of the glass will increase; if the weight percentage of soda ash is too high, the chemical stability of the glass will decrease.

[0027] Glauber's salt refers to anhydrous Glauber's salt (Na2SO4). Both Glauber's salt and carbon powder are glass clarifying agents. Too high or too low a weight of Glauber's salt and carbon powder will affect the clarification effect of the glass melt. Among them, carbon powder acts as a reducing agent, reducing Glauber's salt to easily decomposed Na2S, lowering the decomposition temperature of Glauber's salt, and promoting the clarification reaction.

[0028] This invention, by controlling the weight proportions of each raw material within the aforementioned range, provides an effective amount of initial CO2 bubble nuclei during the heating process of the glass batch. This provides nucleation and attachment sites for the gas (O2) released by the subsequent clarifying agent. O2 diffuses into the existing CO2 bubble nuclei, causing them to expand in volume and increase buoyancy, thereby accelerating their upward movement and discharge. Furthermore, the fluxing advantage of wollastonite is effectively utilized, contributing to the formation of a stable, low-viscosity system and promoting the homogenization of the molten glass, thus improving the clarification effect. Therefore, this invention can reduce bubble defects in finished glass products, thereby improving the quality of the finished glass products.

[0029] According to some embodiments of the present invention, the weight parts of wollastonite are defined as x and the weight parts of limestone are defined as y, where x and y satisfy: 0.46≤x / (x+y)≤0.56.

[0030] When the weight parts x of wollastonite and the weight parts y of limestone satisfy 0.46 ≤ x / (x+y) ≤ 0.56, x / (x+y) can be any value between 0.46 and 0.56. For example, x / (x+y) can be 0.46, 0.47, 0.48, 0.49, 0.50, 0.51, 0.52, 0.53, 0.54, 0.55, or 0.56. When 0.46 ≤ x / (x+y) ≤ 0.56, on the one hand, an effective amount of initial CO2 bubble nuclei can be provided during the heating process of the glass batch, thereby providing nucleation and attachment sites for the gas (O2) released by the subsequent clarifying agent. O2 will diffuse into the existing CO2 bubble nuclei, causing them to expand in volume and increase buoyancy, thereby accelerating their upward discharge. On the other hand, the fluxing advantage of wollastonite can be effectively utilized, which helps to form a stable low-viscosity system, helps to promote the homogenization of the glass melt, and thus improves the clarification effect. When 0.57 < x / (x+y) ≤ 1, the glass batch contains a relatively large amount of wollastonite and a relatively small amount of limestone, resulting in insufficient CO2 bubble nuclei. Although the viscosity of the glass melt is significantly reduced due to the high proportion of wollastonite, the large amount of O2 produced by the decomposition of sodium sulfate cannot find enough "carriers" in the melt, leading to high supersaturation. These supersaturated O2 particles can only nucleate explosively and randomly at certain low-energy interfaces, forming a small number of large, uncontrollable bubbles, thus increasing bubble defects in the finished glass. When 0 < x / (x+y) < 0.46, a small amount of wollastonite is introduced into the glass batch. Due to the fluxing heat of wollastonite, the introduction of a small amount of wollastonite causes the viscosity of the melt to decrease faster in the low-temperature region. The CO2 microbubbles generated by the decomposition of limestone become less stable in this early melt with lower viscosity, and are more likely to merge into irregular large bubbles or float to the surface and be discharged too quickly. O2 cannot be effectively collected in time, resulting in an insufficient number of effective bubble nuclei in the high-temperature refining region where a large number of stable microbubbles are required. At the same time, the irregular large bubbles generated by merging are difficult to discharge, thus increasing the bubble defects in the finished glass.

[0031] According to some embodiments of the present invention, the sodium sulfate content of the glass batch is 2.75% to 2.95%; and / or, the carbon powder content of the glass batch is 2.85% to 3.10%.

[0032] The sodium sulfate content refers to the percentage of Na₂O introduced by sodium sulfate out of the total Na₂O introduced by both sodium sulfate and soda ash. The mass of Na₂O introduced by sodium sulfate can be expressed by formula G. 硝 ×P 硝 Calculate using ×(62 / 142), where 62 is the molar mass of Na2O and 142 is the molar mass of anhydrous Na2SO4; G 硝 P represents the amount of sodium sulfate used in glass batches. 硝The purity of Glauber's salt; the mass of Na₂O introduced by soda ash can be determined by formula G. 碱 ×P 碱 Calculate G by multiplying by (62 / 106). 碱 P represents the amount of soda ash used in the glass batch. 碱 106 represents the purity of soda ash, and 106 represents the molar mass of Na2CO3.

[0033] Carbon powder content refers to the percentage of fixed carbon introduced by carbon powder to the mass of Na2SO4 introduced by sodium sulfate, i.e., carbon powder content = [(carbon powder amount × fixed carbon content in carbon powder) / (sodium sulfate amount × Na2SO4 content in sodium sulfate)] × 100%.

[0034] The sodium sulfate content in the glass batch can be any value between 2.75% and 2.95%. For example, the sodium sulfate content in the glass batch can be 2.75%, 2.77%, 2.80%, 2.82%, 2.85%, 2.90%, 2.92%, or 2.95%. The carbon powder content in the glass batch can be any value between 2.85% and 3.10%. For example, the carbon powder content in the glass batch can be 2.85%, 2.88%, 2.90%, 2.92%, or 2.95%. When the sodium sulfate and carbon powder content are within the above ranges, it helps to improve the clarification effect of the molten glass, thereby helping to reduce bubble defects in the finished glass.

[0035] According to some embodiments of the present invention, wollastonite comprises the following components in mass fractions: SiO2 49.70%~50.70%, Al2O3 0.73%~0.77%, CaO 42.80%~43.40%, MgO 0.79%~0.83%, and Na2O 0.41%~0.43%.

[0036] According to some embodiments of the present invention, silica sand comprises the following mass fractions: SiO2 97.04%~98.08%, Al2O3 0.91%~0.98%, CaO 0.01%~0.05%, Na2O 0.46%~0.55%, K2O 0.02%~0.08%, Fe2O3 0.04%~0.08%; and / or, feldspar comprises the following mass fractions: SiO2 72.10%~73.50%, Al2O3 14.50%~15.50%, CaO 0.20%~0.90%, MgO 0.10%~0.20%, Fe2O3 0.30%~0.37%; and / or, dolomite comprises the following mass fractions: SiO2 0.01%~0.07%, Al2O3 0.01%~0.15%, CaO 30.34%~32.50%, MgO 21.00%~22.25%, Na2O 0.01%~0.05%, Fe2O3 0.01%~0.06%; and / or, limestone comprises the following mass fractions: SiO2 0.10%~0.30%, Al2O3 9.10%~11.05%, CaO 52.41%~56.88%, MgO 0.22%~0.54%, Fe2O3 0.01%~0.05%.

[0037] According to some embodiments of the present invention, the glass comprises the following components by mass fraction: 71%~75% SiO2, 0.5%~2.0% Al2O3, 8%~10% CaO, 2%~5% MgO, 0.1%~0.5% SO3, and 12%~15% alkali metal oxides, wherein the alkali metal oxides include at least one of Na2O and K2O.

[0038] SiO2 is the core material constituting the glass network, mainly introduced from silica sand. Too low a SiO2 content reduces the glass's chemical stability and mechanical strength; too high a SiO2 content leads to excessively high melting temperatures. Al2O3 effectively inhibits phase separation in glass, contributing to improved chemical stability and mechanical strength. It is mainly introduced from feldspar raw materials. Too low an Al2O3 content affects the glass's chemical stability and mechanical strength; too high an Al2O3 content leads to excessively high melting temperatures and crystallization upper limits. CaO reduces the high-temperature viscosity of glass, mainly introduced from limestone and dolomite. Too low a CaO content affects the high-temperature viscosity; too high a CaO content leads to shorter glass thickness, increased brittleness, and increased crystallization tendency. MgO reduces the high-temperature viscosity of glass, decreasing its crystallization tendency and rate. It is mainly introduced from dolomite. Too low a MgO content affects the high-temperature viscosity; too high a MgO content reduces the glass's thermal, chemical, and mechanical stability.

[0039] Alkali metal oxides can reduce the high-temperature viscosity of glass and increase its linear expansion coefficient. These oxides can be introduced from silica sand, feldspar raw materials, soda ash, etc. Too low an alkali metal oxide content will increase the melting temperature of the glass, while too high a content will reduce its chemical stability, particularly its resistance to hydrolysis. SO3 is mainly introduced through sodium sulfate.

[0040] The macroscopic properties of glass (such as viscosity and clarity) are determined by its microstructure, namely the network of [SiO4] and [AlO4] tetrahedra, which can be modified by CaO, MgO, Al2O3, and alkali metal oxides. The content of Al2O3 and alkali metal oxides represents the approximate total amount of [AlO4] tetrahedra in the glass system that need to be stabilized through charge balance (because alkali metal ions are the main charge providers). The difference (2a-b) can be approximated as the amount of divalent cations remaining after exceeding the requirements for balancing [AlO4], which can be freely used to break the silicon-oxygen network. Therefore, by controlling the weight ratio of each raw material component, this invention can ensure that the content of the glass components is within the aforementioned range, and that the content of CaO, MgO, Al2O3, and alkali metal oxides is between 0.95 < (2a-b) / (c+d) < 1.06. This effectively reduces the high-temperature viscosity of the glass and stabilizes its network structure. On the one hand, the overall reduction in the viscosity of the molten glass helps promote the expulsion of bubbles; on the other hand, the increased chemical stability of the entire glass network structure at high temperatures helps suppress the formation of new bubbles. Therefore, the glass of this invention, by combining the method of promoting bubble expulsion with suppressing the formation of new bubbles, can reduce bubble defects in the finished glass product, thereby improving the quality of the finished glass product.

[0041] In some embodiments, the glass also includes 0.05wt% to 0.09wt% of Fe2O3.

[0042] Fe2O3 can color glass and help reduce its transmittance in the ultraviolet and visible light bands. Its mass fraction is 0.05%~0.09%. If the mass fraction of Fe2O3 is too high, it will reduce the heat absorption capacity of the glass; if the mass fraction of Fe2O3 is too high, it will reduce the transmittance of the glass. In some embodiments, Fe2O3 is mainly introduced from impurities in the raw materials.

[0043] According to some embodiments of the present invention, the number of residual bubbles in the glass is 2 to 3.

[0044] The presence of 2-3 residual bubbles in the glass indicates fewer bubble defects and higher quality finished glass. In some embodiments, the number of residual bubbles in the glass can be represented by the number of residual bubbles after the glass raw material is held at 1450℃ for 2 hours. Specifically, this can be tested using a GWC-ii-1700 high-temperature visual melting test furnace: a transparent quartz crucible is used as the container, the raw material is placed in the quartz crucible, and during the heating process of the quartz crucible in the high-temperature furnace, a high-definition high-temperature camera is used as the visual acquisition device to collect real-time images and temperature data of the raw material in the quartz crucible. At the clarification temperature, relevant parameters of bubble generation in the molten glass are recorded. After image processing software, the reaction, melting, and bubble status of the glass material during the heating process are clearly and intuitively reflected.

[0045] According to some embodiments of the present invention, the glass is defined as melting to a viscosity of 10 during the cooling process. 4 The temperature at dpa·s is the operating temperature T of the glass. w T w Satisfies: 1020℃≤T w ≤1022℃.

[0046] In some embodiments, the operating temperature of the glass can be tested using an Orton RSV 1600 rotary high-temperature viscometer, with reference to ASTM C-965.

[0047] According to some embodiments of the present invention, the present invention also provides a method for preparing glass, comprising the following steps: providing the following raw materials in parts by weight: 679-713 parts silica sand, 4-40 parts feldspar, 39-59 parts wollastonite, 129-154 parts dolomite, 42-55 parts limestone, 224-231 parts soda ash, 8-10 parts mirabilite, and 0.3-0.4 parts carbon powder; mixing the raw materials evenly to obtain a glass batch; melting the glass batch to obtain molten glass; conveying the molten glass to a tin bath for float glass forming to obtain a solid glass strip; and annealing the solid glass strip to obtain glass.

[0048] The raw materials can be mixed using a high-powered mixer for 2 to 5 minutes. The process of conveying the molten glass to a tin bath for float glass forming is a conventional technique in this field, and this invention does not impose any specific limitations on it.

[0049] According to some embodiments of the present invention, the step of melting glass batch to obtain glass melt includes: melting glass batch at 1400℃~1600℃ for 5h~10h; and / or, the step of annealing solid glass strip to obtain glass includes: annealing solid glass strip at 500℃~700℃ for 1h~5h.

[0050] The melting of glass batches can be achieved through a melting furnace (horizontal flame regenerative furnace). The melting furnace is generally divided into five functional zones: the pre-melting zone is used for dehydration and decomposition of glass batches; the melting zone is used for silicate reaction to form glass melt; the refining zone is used for decomposition of sodium sulfate to generate SO2 bubbles and remove microbubbles; the homogenizing zone is used to eliminate streaks and make the glass melt composition uniform; and the cooling zone is used to cool the glass melt to the working temperature.

[0051] The melting temperature of the glass batch can be any value between 1400℃ and 1600℃. For example, the melting temperature of the glass batch can be 1400℃, 1425℃, 1450℃, 1475℃, 1500℃, 1525℃, 1550℃, 1575℃, or 1600℃. The melting time of the glass batch can be any value between 5h and 10h. For example, the melting time of the glass batch can be 5h, 6h, 7h, 8h, 9h, or 10h. Melting the glass batch at 1400℃~1600℃ for 5h~10h helps to ensure the complete melting and clarification of the glass batch.

[0052] Annealing of solid glass ribbons can be achieved in an annealing furnace, primarily to eliminate internal stress. The annealing temperature can be any value between 500℃ and 700℃; for example, the annealing temperature can be 500℃, 525℃, 550℃, 575℃, 600℃, 625℃, 650℃, 675℃, or 700℃. The annealing time can be any value between 1 hour and 5 hours; for example, the annealing time can be 1 hour, 2 hours, 3 hours, 4 hours, or 5 hours.

[0053] According to some embodiments of the present invention, the particle size of wollastonite is 200 mesh to 400 mesh.

[0054] A wollastonite particle size of 200-400 mesh means that the particle size of the wollastonite particle group is all between 200 and 400 mesh. There are no larger particles than 200 mesh, and very few ultrafine powders finer than 400 mesh. The particle size of wollastonite can be any value between 200 and 400 mesh; for example, the particle size of wollastonite can be 200 mesh, 250 mesh, 300 mesh, 350 mesh, or 400 mesh. A wollastonite particle size of 200-400 mesh contributes to more complete melting and a more uniform composition of the molten glass.

[0055] The present invention will be further described below through specific embodiments. Unless otherwise specified, the experimental materials used in the embodiments can be purchased from conventional biochemical reagent companies.

[0056] Example The raw materials used in Examples 1-16 and Comparative Examples 1-6 are shown in Tables 1 and 2.

[0057] Table 1 Glass batching table for Examples 1-16

[0058] Table 2 Glass Batch List for Comparative Examples 1-6

[0059] The composition of wollastonite includes the following mass fractions: SiO2 50.2%, Al2O3 0.75%, CaO 43.1%, MgO 0.81%, Na2O 0.42%, Fe2O3 0.38%. Feldspar includes the following mass fractions: SiO2 72.50%, Al2O3 15.10%, CaO 0.60%, MgO 0.13%, Fe2O3 0.35%. Silica sand includes the following mass fractions: SiO2 98.04%, Al2O3 0.95%, CaO 0.01%, Na2O 0.51%, K2O 0.06%, Fe2O3 0.07%. Dolomite includes the following mass fractions: SiO2 0.04%, Al2O3 0.09%, CaO 31.34%, MgO 21.09%, Na2O 0.02%, Fe2O3 0.04%. Limestone comprises the following mass fractions: SiO2 0.17%, Al2O3 10.05%, CaO 54.88%, MgO 0.44%, and Fe2O3 0.02%.

[0060] After the raw materials in Examples 1-16 and Comparative Examples 1-7 are mixed evenly, a glass batch is obtained. The glass batch is kept at 1450°C for 6 hours to obtain molten glass. The molten glass is transported to a tin bath for float forming to obtain a solid glass strip. The solid glass strip is annealed at 600°C for 2 hours to obtain glass.

[0061] Test methods Operating temperature: The high-temperature viscosity profile of the glass was tested using an Orton RSV 1600 rotary viscometer according to ASTM C-965, where the viscosity was 10. 4 The temperature corresponding to dpa·s is the operating point temperature T. w .

[0062] Residual bubble count: The glass batch was placed in a quartz crucible, which was then placed in a GWC-ii-1700 high-temperature visual melting test furnace. The equipment was then started to conduct a high-temperature visual melting observation experiment. The heating curves of the high-temperature visual melting test furnace were set as follows: 25℃~200℃, heating rate 5℃ / min; 200℃~1200℃, heating rate 10℃ / min; 1200℃~1450℃, heating rate 5℃ / min; and a holding time of 1450℃ for 120 min. Afterward, the number of residual bubbles in the glass melt was counted.

[0063] CO2 emissions per year from a 900T / D melting furnace: Based on the GB / T 32151.7-2023 standard ("Carbon Emission Accounting and Reporting Requirements Part 7: Flat Glass Manufacturing Enterprises"), and combined with the design composition of the glass formulation, the theoretical annual carbon emissions after application to a 900T / D melting furnace are calculated.

[0064] Test Results The test results of Examples 1-16 and Comparative Examples 1-7 are shown in Table 4.

[0065] Table 4 shows the test results of Examples 1-16 and Comparative Examples 1-7.

[0066] As can be seen from Table 1, the working temperature of the glass in Examples 1 to 16 of the present invention is all below 1022℃. After completing the high-temperature imaging experiment, the number of residual bubbles is 2 to 3. After the glass of the present invention is applied to a 900T / D melting furnace, the annual CO2 emission is 59255t to 61687t, which is 5478t to 7910t less than the classic float glass formula (Comparative Example 1).

[0067] The glass batches of Comparative Examples 1 and 2 did not contain wollastonite, only limestone. The operating temperature of the glass in Comparative Example 1 was 1037°C. This glass formulation, applied in a 900T / D melting furnace, resulted in annual CO2 emissions of 67,165 tons, and 10 residual bubbles were observed after a high-temperature visual experiment. The operating temperature of the glass in Comparative Example 2 was 1025°C. This glass formulation, applied in a 900T / D melting furnace, resulted in annual CO2 emissions of 66,183 tons, and 5 residual bubbles were observed after a high-temperature visual experiment. Therefore, the carbon emissions of Comparative Examples 1 and 2 were both higher than those of the embodiments of this invention.

[0068] In Comparative Examples 3 and 4, x / (x+y) is 0.25, and in Comparative Examples 5 and 6, x / (x+y) is 0.85. The number of residual bubbles after the high-temperature imaging experiment in Comparative Examples 3-6 are 35, 16, 33, and 15, respectively, which are all much higher than those in the embodiments of the present invention. This shows that the present invention can effectively reduce glass bubble defects by controlling x / (x+y) between 0.46 and 0.56. Although x / (x+y) in Comparative Example 7 meets the scope of the present invention, the weight parts of its components such as silica sand, wollastonite, limestone, and dolomite are not within the scope of the present invention, resulting in higher operating temperature and bubble number than those in the embodiments of the present invention.

[0069] The high-temperature visual observation results of the glass batch material in Example 10 of this invention at 1450℃ for different holding times are as follows: Figure 1As shown, the high-temperature visual observation results of the glass batch material in Comparative Example 3 at 1450℃ for different holding times are as follows: Figure 2 As shown, the high-temperature visual observation results of the glass batch material in Comparative Example 4 at 1450℃ for different holding times are as follows: Figure 3 As shown, the high-temperature visual observation results of the glass batch material in Comparative Example 6 at 1450℃ for different holding times are as follows: Figure 4 As shown. Comparison Figures 1-4 As can be seen, the number of bubbles in the glass batch material after the high-temperature visual test in the embodiments of the present invention is significantly reduced, thus the quality of the finished glass product of the present invention is higher.

[0070] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A type of glass, characterized in that, The glass batch comprises the following raw materials in parts by weight: 679-713 parts silica sand, 4-40 parts feldspar, 39-59 parts wollastonite, 129-154 parts dolomite, 42-55 parts limestone, 224-231 parts soda ash, 8-10 parts mirabilite, and 0.3-0.4 parts carbon powder.

2. The glass as described in claim 1, characterized in that, Let x be the weight part of wollastonite and y be the weight part of limestone, where x and y satisfy: 0.46 ≤ x / (x+y) ≤ 0.

56.

3. The glass as described in claim 1, characterized in that, The sodium sulfate content in the glass batch is 2.75% to 2.95%; and / or, the carbon powder content in the glass batch is 2.85% to 3.10%.

4. The glass according to any one of claims 1 to 3, characterized in that, The wollastonite comprises the following components by mass fraction: SiO249.70%~50.70%, Al2O30.73%~0.77%, CaO 42.80%~43.40%, MgO 0.79%~0.83%, Na2O0.41%~0.43%.

5. The glass according to any one of claims 1 to 3, characterized in that, The silica sand comprises the following components by mass fraction: SiO2 97.04%~98.08%, Al2O3 0.91%~0.98%, CaO 0.01%~0.05%, Na2O 0.46%~0.55%, K2O 0.02%~0.08%, Fe2O3 0.04%~0.08%; and / or, The feldspar comprises the following mass fractions: SiO2 72.10%~73.50%, Al2O3 14.50%~15.50%, CaO 0.20%~0.90%, MgO 0.10%~0.20%, Fe2O3 0.30%~0.37%; and / or, The dolomite comprises the following mass fractions: SiO2 0.01%~0.07%, Al2O3 0.01%~0.15%, CaO 0.34%~32.50%, MgO 21.00%~22.25%, Na2O 0.01%~0.05%, Fe2O3 0.01%~0.06%; and / or, The limestone comprises the following mass fractions: SiO2 0.10%~0.30%, Al2O3 9.10%~11.05%, CaO 52.41%~56.88%, MgO 0.22%~0.54%, and Fe2O3 0.01%~0.05%.

6. The glass according to any one of claims 1 to 5, characterized in that, The glass has 2 to 3 residual bubbles after being kept at 1450℃ for 2 hours.

7. The glass according to any one of claims 1 to 5, characterized in that, The glass is defined as melting to a viscosity of 10 during the cooling process. 4 The temperature at dpa·s is the operating temperature T of the glass. w The T w Satisfies: 1020℃≤T w ≤1022℃.

8. A method for preparing glass according to any one of claims 1 to 7, characterized in that, Includes the following steps: The following raw materials are provided in parts by weight: silica sand 679-713 parts, feldspar 4-40 parts, wollastonite 39-59 parts, dolomite 129-154 parts, limestone 42-55 parts, soda ash 224-231 parts, mirabilite 8-10 parts, and carbon powder 0.3-0.4 parts. The raw materials are mixed evenly to obtain the glass batch; The batch material is melted to obtain molten glass; The molten glass is transported to a tin bath for float glass forming to obtain a solid glass strip; The solid glass strip is annealed to obtain glass.

9. The method for preparing glass according to claim 8, characterized in that, The step of melting the glass batch to obtain molten glass includes: The glass batch is melted at 1400℃~1600℃ for 5h~10h; and / or, The step of annealing the solid glass strip to obtain glass includes: The solid glass strip is annealed at 500℃~700℃ for 1h~5h.

10. The method for preparing glass according to claim 8 or 9, characterized in that, The wollastonite has a particle size of 200-400 mesh.

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