Manufacturing method for glass articles

Abstract

To provide a method for manufacturing glass articles that can reduce the energy required for the production of glass articles. [Solution] A method for manufacturing glass articles, comprising: heating and melting the glass raw material in a melting furnace to produce molten glass; using at least one of the waste heat generated in the melting furnace and the waste heat generated in a molding section connected to the melting furnace for molding the molten glass, dewatering a water-containing raw material under at least one of the following conditions 1 and 2 to obtain a dewatered raw material; and adding the dewatered raw material to the glass raw material. Condition 1: The above-mentioned water-containing raw material is boric acid, and the temperature of the water-containing raw material during dehydration is 170°C or lower. Condition 2: The above-mentioned water-containing raw material is one or more chloride raw materials selected from the group consisting of strontium chloride, calcium chloride, and magnesium chloride, and the temperature of the water-containing raw material during dehydration is 250°C or lower.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing glass articles.

Background Art

[0002] Due to its properties, various uses of glass have been studied for a long time. Although various types of glass are known, for example, glass containing boron has been widely studied.

[0003] Patent Document 1 discloses a glass containing a predetermined amount of B2O3 and SiO2 and having a total content of La2O3, Y2O3, Gd2O3, and Yb2O3 within a predetermined range. In the above patent document, it is described that oxides and boric acid are used as raw materials and melted to produce glass.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a result of the study by the present inventors, it has been found that there is room for reducing the energy required for manufacturing glass articles by using boric acid as a raw material and melting the glass as described above. In addition, chloride raw materials may be used as glass raw materials, and it has also been found that there is room for reducing the energy required for manufacturing glass articles even when chloride raw materials are used.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a method for manufacturing a glass article capable of reducing the energy required for manufacturing the glass article.

Means for Solving the Problems

[0007] As a result of diligent research into the above-mentioned problems, the inventors of the present invention discovered that the energy required for manufacturing glass articles can be reduced by using waste heat to dehydrate the raw materials under predetermined temperature conditions, leading to the present invention.

[0008] In other words, the inventors found that the above problem could be solved by the following configuration. [1] A method for manufacturing glass articles, which involves using glass raw materials to produce molten glass and then manufacturing glass articles, The above glass raw materials are heated and melted in a melting furnace to produce the above molten glass. Using at least one of the waste heat generated in the melting furnace and the waste heat generated in the molding section connected to the melting furnace for molding the molten glass, the water-containing raw material is dehydrated under at least one of the following conditions 1 and 2 to obtain the dehydrated raw material. A method for manufacturing glass articles, comprising adding the above-mentioned dehydrated raw material to the above-mentioned glass raw material. Condition 1: The above-mentioned water-containing raw material is boric acid, and the temperature of the above-mentioned water-containing raw material during dehydration is 170°C or lower. Condition 2: The above-mentioned water-containing raw material is one or more chloride raw materials selected from the group consisting of strontium chloride, calcium chloride, and magnesium chloride, and the temperature of the above-mentioned water-containing raw material during dehydration is 250°C or lower. [2] The method for producing a glass article according to [1], wherein the water-containing raw material is heated and stirred during the dehydration of the water-containing raw material. [3] A method for manufacturing a glass article according to [1] or [2], wherein a reduced pressure is applied during the dehydration of the water-containing raw material. [4] A method for producing a glass article according to [1] or [2], wherein the above-mentioned water-containing raw material is boric acid. [5] A method for producing a glass article according to [1] or [2], wherein the above-mentioned water-containing raw material is the above-mentioned chloride raw material. [6] A method for producing a glass article according to [1] or [2], wherein the above-mentioned water-containing raw material is strontium chloride. [7] A method for manufacturing a glass article according to [1] or [2], wherein the dehydrated raw material is stored in a dry state before being added to the glass raw material. [8] The method for manufacturing a glass article according to [7], wherein the glass raw material is stored in a drying facility, and at least one selected from the group consisting of dry air, dry nitrogen gas, dry oxygen gas, and dry argon gas is introduced into the drying facility. [9] A method for manufacturing glass articles according to [8] or [9], wherein the pressure inside the drying equipment is maintained at a positive pressure.

[10] A method for manufacturing glass articles according to any one of [8] to

[10] , wherein the relative humidity inside the drying equipment is kept below 30%. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a method for manufacturing glass articles that can reduce the energy required for the manufacture of glass articles. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic plan view of an example of a glass manufacturing apparatus capable of carrying out the manufacturing method for glass articles of the present invention. [Modes for carrying out the invention]

[0011] The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, glass composition is expressed in mole percentages based on oxides, and mole% may be simply written as %. Furthermore, the "~" symbol indicating a numerical range is used to mean that the values ​​before and after it are included as the lower and upper limits, respectively. In the drawings of this specification, some parts of the structure may be exaggerated or simplified for illustrative purposes. Furthermore, the dimensional ratios of each part may differ from those of the actual components.

[0012] <Method of manufacturing glass articles> The method for manufacturing a glass article of the present invention manufactures molten glass using glass raw materials and manufactures a glass article. Here, in the method for manufacturing a glass article of the present invention, glass raw materials are heated and melted in a melting furnace to generate the above molten glass, and at least one of the exhaust heat generated in the melting furnace and the exhaust heat generated in a forming part connected to the melting furnace for forming the molten glass is used to dehydrate a hydrous raw material under at least one of the following Condition 1 and the following Condition 2 to obtain a dehydrated raw material, and the dehydrated raw material is added to the glass raw material. Condition 1: The hydrous raw material is boric acid, and the temperature of the hydrous raw material during dehydration is 170°C or lower. Condition 2: The hydrous raw material is one or more chloride raw materials selected from the group consisting of strontium chloride, calcium chloride, and magnesium chloride, and the temperature of the hydrous raw material during dehydration is 250°C or lower. That is, the method for manufacturing a glass article of the present invention has a melting step of manufacturing molten glass in a melting furnace using glass raw materials, and a dehydrated raw material is added to the glass raw materials in the melting step. Further, the method for manufacturing a glass article of the present invention has a dehydration step of dehydrating a hydrous raw material under at least one of the above Condition 1 and the above Condition 2 using at least one of the exhaust heat generated in the melting furnace and the exhaust heat generated in a forming part connected to the melting furnace for forming the molten glass to obtain a dehydrated raw material. In addition, hereinafter, the temperature of the hydrous raw material during dehydration in the above Condition 1 and the above Condition 2 is also referred to as the "dehydration temperature" hereinafter.

[0013] According to the method for manufacturing a glass article of the present invention, the energy required for manufacturing the glass article can be reduced. This is because, first, if a hydrous raw material (the above boric acid and chloride raw materials) is directly supplied to a melting furnace to obtain molten glass, it can be said that energy is required to evaporate the moisture contained in the hydrous raw material. On the other hand, exhaust heat is generated in the melting furnace and the forming part, and by effectively using this exhaust heat and evaporating the moisture contained in the hydrous raw material in advance, the energy required for melting the glass can be reduced. In the method for manufacturing a glass article of the present invention, dehydration of the water-containing raw material is performed within a predetermined temperature range. When dehydration of the water-containing raw material is performed within the above-mentioned predetermined temperature range, the obtained dehydrated raw material is likely to be obtained in a property suitable for melting (for example, powdery or granular), additional crushing treatment or grinding treatment is unnecessary, and the energy required for manufacturing the glass article can be reduced.

[0014] Hereinafter, the method for manufacturing a glass article of the present invention will be described with reference to the drawings.

[0015] The method for manufacturing a glass article of the present invention can be implemented, for example, by a glass manufacturing apparatus 10 shown in FIG. 1. FIG. 1 shows a schematic plan view of a glass manufacturing apparatus 10 capable of implementing the method for manufacturing a glass article of the present invention. The glass manufacturing apparatus 10 shown in FIG. 1 includes a melting furnace 12, a forming section 14, an annealer 16, a heat exchanger 22, a heat medium heating device 24, and a dryer 26. In the melting furnace 12, the above-mentioned melting step is performed. In the dryer 26, the above-mentioned dehydration step is performed. The melting furnace 12 has a raw material inlet 12a and a glass outlet 12b, and is a device that heats the glass raw material introduced from the raw material inlet 12a to melt the glass raw material and generate molten glass. A feeder 12c is connected to the glass outlet 12b of the melting furnace, and the molten glass melted in the melting furnace 12 is supplied to the forming section 14 through the feeder 12c. The forming section 14 is a device that forms the molten glass supplied from the feeder 12c into a desired shape. The annealer 16 is supplied with the glass formed in the forming section 14 and removes the strain of the glass formed in the forming section 14. In the glass manufacturing apparatus 10, a glass article is obtained by the above procedure.

[0016] Here, a flue 18a is connected to the melting furnace 12, and the flue 18a is a flow path for discharging high-temperature gas to the outside as waste heat. A heat exchanger 22a is located inside the flue 18a, and the medium introduced into the heat exchanger 22a is heated by the high-temperature gas passing through the flue 18a. The medium supplied to the heat exchanger 22a is circulated between the heat medium heating device 24 and the heat exchanger 22a by the pump 20a, and the waste heat obtained from the high-temperature gas passing through the flue 18a is transferred from the heat exchanger 22a to the heat medium heating device 24. Furthermore, a flue 18b is connected to the molding section 14, and the flue 18b is a passage for releasing high-temperature gas to the outside as waste heat. A heat exchanger 22b is located inside the flue 18b, and the medium introduced into the heat exchanger 22b is heated by the high-temperature gas passing through the flue 18b. The medium supplied to the heat exchanger 22b is circulated between the heat transfer medium heating device 24 and the heat exchanger 22b by the pump 20b, and the waste heat obtained from the high-temperature gas passing through the flue 18b is transferred from the heat exchanger 22b to the heat transfer medium heating device 24. The heat transfer medium heating device 24 is connected to the dryer 26 and supplies heated gas to the dryer 26 to dry the water-containing raw material contained inside the dryer 26, thereby dewatering the water-containing raw material. The heated gas is generated using the heat from the medium supplied to the heat transfer medium heating device 24. In other words, the glass manufacturing apparatus 10 utilizes waste heat from the melting furnace 12 and the molding section 14 to generate heated gas, which is then used to dehydrate the water-containing raw material in the dryer 26.

[0017] The water-containing raw materials dehydrated in the dryer 26 include boric acid and at least one chloride raw material selected from the group consisting of strontium chloride, calcium chloride, and magnesium chloride. In this specification, boric acid refers to orthoboric acid, which has the chemical formula H3BO3. In this specification, strontium chloride refers to the hydrate of SrCl2. In this specification, calcium chloride refers to the hydrate of CaCl2. In this specification, magnesium chloride refers to the hydrate of MgCl2. As described above, when the water-containing raw material is boric acid, the dehydration temperature is 170°C or lower (condition 1 above), preferably 160°C or lower, more preferably 150°C or lower, and even more preferably 145°C or lower. Furthermore, when the water-containing raw material is boric acid, the dehydration temperature is preferably 100°C or higher, more preferably 110°C or higher, even more preferably 120°C or higher, and particularly preferably 130°C or higher. Furthermore, as mentioned above, when the water-containing raw material is the chloride raw material, the dehydration temperature is 250°C or lower (condition 2 above), preferably 220°C or lower, and more preferably 200°C or lower. Also, when the water-containing raw material is the chloride raw material, the dehydration temperature is preferably 100°C or higher, and more preferably 120°C or higher.

[0018] The dewatering time in the dewatering process can be adjusted as appropriate, but for example, 0.5 hours or more is preferred, 1 hour or more is more preferred, and 2 hours or more is even more preferred. In addition, the above dewatering time is often 24 hours or less, 12 hours or less is preferred, and 6 hours or less is more preferred.

[0019] The dewatering method in the dryer 26 is not particularly limited as long as dewatering can be performed at the above dewatering temperature, and various dewatering methods can be applied. Among these, heating and stirring the water-containing raw material is preferred as a dewatering method. By heating and stirring the water-containing raw material to dewater it, it is easier to obtain a dewatered raw material with properties suitable for the melting process (e.g., powder or granules). Furthermore, reducing the pressure is also preferred as a dewatering method. Examples of the types of dryers 26 include fluidized bed dryers, jet bed dryers, airflow dryers, vacuum dryers, rotary dryers, groove-type agitated dryers, cylinder dryers, and conical rotary dryers. Among these, fluidized bed dryers or rotary dryers are preferred. A rotary dryer, also called a rotary dryer, is a device in which agitator blades are installed inside a cylindrical drying container, and hot air is supplied into the drying container while stirring the powder inside to dry the powder. In a rotary dryer, it is preferable that the bottom surface of the cylindrical drying container is inclined in the vertical direction from a plane perpendicular to the direction of gravity. The dryer 26 may be a device that performs drying in multiple stages using two or more different types of equipment. Alternatively, the dryer 26 may be a device that combines the features of two or more different types of equipment. For example, the vacuum dryer may be a vacuum dryer that can perform at least one of stirring and heating.

[0020] When dewatering the water-containing raw material in the dryer 26, the amount of water-containing raw material to be processed is not particularly limited, for example, 10 kg or more, preferably 20 kg or more, and more preferably 50 kg or more. Also, although the amount of water-containing raw material to be processed is not particularly limited, for example, 5000 kg or less.

[0021] It is also preferable that the container for holding the water-containing raw material in the dryer 26 does not allow the water-containing raw material to adhere to it, or at least does not allow it to adhere easily. One way to prevent the water-containing raw material from adhering to the container for holding the water-containing raw material in the dryer 26 is to appropriately control the heating temperature and heating time. Specifically, when dehydrating boric acid as a water-containing raw material, one method involves maintaining the dehydration temperature at 120°C to generate steam, maintaining the dehydration temperature at 120°C until the amount of steam generated decreases, and then raising the dehydration temperature to 140°C after the amount of steam generated decreases.

[0022] In the dryer 26 shown in Figure 1, as described above, the waste heat generated in the melting furnace 12 is transferred to the heat transfer medium heating device 24 via the heat exchanger 22, where heated gas is generated and supplied to the dryer 26. The heating gas supplied to the dryer 26 is not particularly limited and may include inert gases such as nitrogen gas or argon gas, and active gases such as oxygen gas and air. The heating gas may be supplied directly to the water-containing raw material contained inside the dryer 26 to heat the water-containing raw material, or it may be heated by heat transfer to heat the containment container of the dryer 26 and at least one of the components placed inside the containment container. Furthermore, when heating is performed by directly supplying heated gas to the water-containing raw material in the dryer 26, the temperature of the heated gas supplied to and discharged from the dryer 26 is often approximately the same as, or lower than, the temperature of the water-containing raw material.

[0023] The dewatering temperature in the dryer 26 can be adjusted, for example, by the amount of heated gas supplied from the heat transfer medium heating device 24 to the dryer 26, and the temperature of the heated gas supplied from the heat transfer medium heating device 24 to the dryer 26.

[0024] The configuration of the heat exchanger 22 is not particularly limited, and any configuration of a known heat exchanger can be adopted as appropriate. Furthermore, the configurations of the pump 20 and the heat transfer medium heating device 24 are not particularly limited, and known devices can be used. Furthermore, in the above embodiment, a heated gas was supplied from the heat transfer medium heating device 24, but it may also be an embodiment in which a heated liquid is supplied.

[0025] When the water-containing raw material is dehydrated in the dryer 26, dehydrated raw material is obtained (dehydration process). In dehydrated raw materials, the moisture content is reduced compared to hydrated raw materials. When boric acid (orthoboric acid) is used as the hydrated raw material, dehydrated raw materials containing metaboric acid (chemical formula: HBO2) are often obtained. Furthermore, when chloride raw materials are used as the hydrated raw materials, the chloride raw materials are often hydrates containing water molecules, but in dehydrated raw materials, the water molecule content of the above chloride raw materials decreases. In the method for manufacturing glass articles of the present invention, the dehydrated raw material obtained is added to the melting furnace 12 as a glass raw material to be heated and melted. The waste heat generated in the melting process is used in the drying process. In the method for manufacturing glass articles of the present invention, since molten glass is produced using dehydrated raw materials, the amount of water incorporated into the glass is easily reduced, and glass articles with a low β-OH value are easily obtained.

[0026] The dehydrated raw material obtained in the dehydration process may be stored before being subjected to the melting process, that is, before being added to the glass raw material. Alternatively, it is preferable to store the dehydrated raw material in a dry state before adding it to the glass raw material. One method for storing dehydrated raw materials in a dry state is to store them in a raw material storage container maintained at a predetermined humidity. The predetermined humidity is a relative humidity of 30% or less, preferably 15% or less, and more preferably 10% or less. It is also preferable that the raw material storage container be maintained at positive pressure. One method for maintaining a predetermined humidity and positive pressure inside a raw material storage container is to supply a dry gas into the container. Examples of dry gases include at least one selected from the group consisting of dry air, dry nitrogen gas, dry oxygen gas, and dry argon gas.

[0027] Furthermore, the method of the melting process is not particularly limited, and known methods can be used. For example, the melting process can be carried out by supplying glass raw materials from a raw material inlet 12a to a melting furnace 12 having a heating means, heating the glass raw materials, and melting them. The composition of the manufactured glass articles is described below.

[0028] The glass articles produced by the glass article manufacturing method of the present invention contain components derived from the above-mentioned boric acid and chloride raw materials. The glass articles are not particularly limited as long as they contain the above components, and may be any of soda-lime glass, mixed alkali glass, borosilicate glass, or alkali-free glass.

[0029] If the glass article is soda-lime glass, its composition is preferably expressed as a mass percentage based on oxides: SiO2: 65-75%, Al2O3: 0-3%, CaO: 5-15%, MgO: 0-15%, Na2O: 10-20%, K2O: 0-3%, Li2O: 0-5%, Fe2O3: 0-3%, TiO2: 0-5%, CeO2: 0-3%, BaO: 0-5%, SrO: 0-5%, B2O3: 0-5%, ZnO: 0-5%, ZrO2: 0-5%, SnO2: 0-3%, SO3: 0-0.5%.

[0030] Furthermore, if the glass article is a mixed alkali glass, its composition is preferably expressed as a mass percentage based on oxides, with SiO2: 39-75%, Al2O3: 3-27%, B2O3: 0-20%, MgO: 0-13%, CaO: 0-17%, SrO: 0-20%, and BaO: 0-30%.

[0031] Furthermore, if the glass article is borosilicate glass, its composition is preferably expressed as an oxide-based mass percentage of SiO2: 60-85%, Al2O3: 0-5%, B2O3: 5-20%, and Na2O+K2O: 2-10%.

[0032] Furthermore, if the glass article is alkali-free glass, its composition is preferably SiO2: 50-80%, Al2O3: 5-25%, and B2O3: 1-15%, expressed as mass percentages based on oxides, and Na2O+K2O: 0.1% or less.

[0033] The molten glass obtained in the melting process is molded into the desired shape in the molding section 14. The molding section 14 can employ general equipment, such as a float molding machine and a fusion molding machine. The float molding apparatus continuously supplies molten glass to the surface of the molten tin bath in the bathtub, molding the molten glass into a strip. The fusion molding apparatus continuously supplies molten glass into a trough with a roughly V-shaped cross-section, and the molten glass that overflows from both the left and right sides of the trough is merged at the lower edge of the trough to form a strip-shaped material. The glass formed in the molding section 14 is heated in the annealer 16, slowly cooled, and then cut to predetermined dimensions to become glass articles such as glass plates. The annealer 16 in the glass manufacturing apparatus 10 may be omitted. Furthermore, the shape formed in the molding section 14 is not limited to the glass plate described above, and may be formed into any desired shape. Other shapes besides glass plates may include shapes having a predetermined curved surface, such as cylindrical, cylindrical, disc-shaped, spherical, and lens-shaped plates. More specifically, other shapes besides glass plates include shapes for tableware, container shapes for physicochemical testing, and shapes for optical lenses.

[0034] Furthermore, although the embodiment shown in Figure 1 describes a configuration using a heat transfer medium heating device 24, the gas heated in the heat exchangers 22a and 22b by the waste heat from the melting furnace 12 may be directly supplied to the dryer 26. In other words, the heat transfer medium heating device 24 may be omitted. Furthermore, although the embodiment shown in Figure 1 depicts a configuration in which heat exchangers 22a and 22b are connected to the heat transfer medium heating device 24, heat exchangers 22a and 22b may also be connected to independent heat transfer medium heating devices.

[0035] Furthermore, although the embodiment shown in Figure 1 has a flue 18a connected to the melting furnace 12 and a flue 18b connected to the molding section 14, the flue of either the melting furnace 12 or the molding section 14 (either flue 18a or flue 18b) may be omitted. In other words, the water-containing raw material may be dewatered using only the waste heat from the melting furnace 12, or the water-containing raw material may be dewatered using only the waste heat from the molding section 14. Alternatively, the waste heat generated in the annealer 16 may be used to further dehydrate the water-containing raw material. In addition, the manner in which waste heat is utilized in each of the above embodiments is not limited to those embodiments, and known embodiments may be applied. [Examples]

[0036] The present invention will be described in more detail below based on examples. The materials, quantities, proportions, processing details, and processing procedures shown in the following examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the following examples.

[0037] <Dehydration Test> A dehydration test was conducted on boric acid (orthoboric acid), a water-containing raw material, under the following conditions. • Equipment name: Vibrating fluidized bed dryer (manufactured by Kurimoto Iron Works Co., Ltd.) • Water-containing raw material: Boric acid (manufactured by Rio Tinto), 13 kg • Inlet air temperature: 200℃ • Outlet air temperature: 130℃ • Drying time: 3 hours During the dehydration test, the temperature inside the apparatus was checked, and the dehydration temperature (temperature of the water-containing raw material during dehydration) was found to be 145°C.

[0038] When a dehydration test of boric acid was conducted under the above conditions, powdery boric acid was obtained even after dehydration. This powdery boric acid can be used directly as a glass raw material. Furthermore, if the dehydration of the above water-containing raw material is carried out using waste heat, the energy required for the manufacture of glass products can be reduced.

[0039] On the other hand, in the above dehydration test, when drying was performed with the inlet air temperature set to 250°C, the dehydration temperature (temperature of the water-containing raw material during dehydration) exceeded 170°C, and when the dehydration temperature exceeded 170°C, lumpy boric acid was generated. Furthermore, when the dehydration temperature reached approximately 240°C, boric acid solidified inside the equipment. In the case of the boric acid described above, it is necessary to crush the boric acid, which is undesirable from the standpoint of reducing the energy required for the manufacture of glass products. Furthermore, if boric acid solidifies inside the equipment, it becomes difficult to remove and recover, which is also undesirable from the standpoint of operational efficiency. [Explanation of Symbols]

[0040] 10 Glass manufacturing equipment 12. Melting furnace 12a Raw material input port 12b Glass outlet 12c Feeder 14 Molding section 16 Annealer 18a,18b flue 20a, 20b pumps 22a,22b Heat exchanger 24 Heat medium heating device 26 Dryer

Claims

1. A method for manufacturing glass articles, which involves producing molten glass using glass raw materials and manufacturing glass articles, The glass raw material is heated and melted in a melting furnace to produce the molten glass. Using at least one of the waste heat generated in the melting furnace and the waste heat generated in the molding section connected to the melting furnace for molding the molten glass, the water-containing raw material is dehydrated under at least one of the following conditions 1 and 2 to obtain the dehydrated raw material. A method for manufacturing a glass article, comprising adding the dehydrated raw material to the glass raw material. Condition 1: The water-containing raw material is boric acid, and the temperature of the water-containing material during dehydration is 170°C or lower. Condition 2: The water-containing raw material is one or more chloride raw materials selected from the group consisting of strontium chloride, calcium chloride, and magnesium chloride, and the temperature of the water-containing material during dehydration is 250°C or lower.

2. A method for manufacturing a glass article according to claim 1, wherein the water-containing raw material is heated and stirred during the dehydration of the water-containing raw material.

3. A method for manufacturing a glass article according to claim 1 or 2, wherein a reduced pressure is applied during the dehydration of the water-containing raw material.

4. A method for producing a glass article according to claim 1 or 2, wherein the water-containing raw material is boric acid.

5. A method for manufacturing a glass article according to claim 1 or 2, wherein the water-containing raw material is the chloride raw material.

6. The method for producing a glass article according to claim 1 or 2, wherein the water-containing raw material is strontium chloride.

7. A method for manufacturing a glass article according to claim 1 or 2, wherein the dehydrated raw material is stored in a dry state before being added to the glass raw material.

8. A method for manufacturing a glass article according to claim 7, wherein the glass raw materials are stored in a raw material storage container, and at least one selected from the group consisting of dry air, dry nitrogen gas, dry oxygen gas, and dry argon gas is introduced into the raw material storage container.

9. The method for manufacturing a glass article according to claim 8, wherein the pressure inside the raw material storage container is maintained at a positive pressure.

10. The method for manufacturing a glass article according to claim 8, wherein the relative humidity inside the raw material storage container is maintained at 30% or less.

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