WO2020004138A1 - Procédé de fabrication d'un article en verre - Google Patents

Procédé de fabrication d'un article en verre Download PDF

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Publication number
WO2020004138A1
WO2020004138A1 PCT/JP2019/024065 JP2019024065W WO2020004138A1 WO 2020004138 A1 WO2020004138 A1 WO 2020004138A1 JP 2019024065 W JP2019024065 W JP 2019024065W WO 2020004138 A1 WO2020004138 A1 WO 2020004138A1
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WO
WIPO (PCT)
Prior art keywords
glass
furnace
temperature
raw material
molten glass
Prior art date
Application number
PCT/JP2019/024065
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English (en)
Japanese (ja)
Inventor
長谷川　徹
陸朗 愛
Original Assignee
日本電気硝子株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日本電気硝子株式会社 filed Critical 日本電気硝子株式会社
Priority to JP2020527424A priority Critical patent/JP7196917B2/ja
Publication of WO2020004138A1 publication Critical patent/WO2020004138A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
    • C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
    • C03B5/235—Heating the glass
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
    • C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
    • C03B5/42—Details of construction of furnace walls, e.g. to prevent corrosion; Use of materials for furnace walls
    • C03B5/43—Use of materials for furnace walls, e.g. fire-bricks

Definitions

  • the present invention relates to a method for producing a glass article, comprising: a step of continuously producing a molten glass as a base of a glass article using a glass melting furnace; and a step of starting up the glass melting furnace to a state where the step can be performed. .
  • Patent Literature 1 discloses an example of a method of continuously producing molten glass using a glass melting furnace.
  • the temperature inside the glass melting furnace is raised from room temperature by the thermal power of the air combustion burner.
  • the temperature in the furnace rises to a temperature at which the glass raw material can be melted (hereinafter, referred to as a melting temperature)
  • the supply of the glass raw material into the furnace is started.
  • the glass raw material is melted and the molten glass is stored in the furnace.
  • the heating of the molten glass stored in the furnace by the electrodes is started.
  • the molten glass to be formed in the furnace is a glass having a high melting temperature, for example, when the glass is non-alkali glass, the following problems occur. there were.
  • alkali-free glass material a glass material for alkali-free glass
  • this alkali-free glass raw material has the property that the melting temperature is higher than other glass raw materials. Due to this, with the thermal power of the air combustion burner, the temperature in the furnace cannot be stably raised to the melting temperature of the alkali-free glass raw material, and the alkali-free glass raw material cannot be sufficiently melted. There was a defect.
  • an oxyfuel combustion burner with a higher thermal power a burner that mixes gaseous fuel and oxygen and burns
  • the temperature in the furnace can be stably increased to the melting temperature of the alkali-free glass raw material.
  • the furnace wall is locally heated, and the refractory (brick) constituting the furnace wall may be damaged due to thermal stress. there were.
  • the present invention for solving the above-described problems is to provide a new method by melting a glass raw material continuously supplied onto the molten glass while electrically heating the molten glass stored in a glass melting furnace whose furnace wall is made of a refractory.
  • a method for manufacturing a glass article, wherein a start-up step includes a first temperature raising step of raising the temperature in a glass melting furnace from room temperature by an air combustion burner, and glass melting by an oxygen combustion burner after the start of the first temperature raising step.
  • a second temperature raising step of raising the temperature in the furnace by the oxyfuel burner is performed.
  • the refractory can be protected from damage because heating the furnace preheated by the air combustion burner with the oxyfuel burner avoids local heating of the furnace wall.
  • the glass raw material is preferably a non-alkali glass raw material.
  • the start-up step is a raw material supply start step of starting supply of the glass raw material into the glass melting furnace, and an electric heating start of starting the electric heating of the molten glass stored by melting the supplied glass raw material.
  • the method further includes the steps of:
  • the energization heating start step can be reliably performed, and the energization heating of the stored molten glass can be reliably started. This makes it possible to start up the furnace more suitably.
  • the refractory preferably includes a refractory having an electrical resistivity of 800 ⁇ ⁇ cm or more at 1400 ° C.
  • the current flows more easily through the molten glass than the refractory material (furnace wall) after the energization heating start step. This is advantageous in eliminating the risk of occurrence.
  • the electrical resistivity of the molten glass at 1400 ° C. is preferably less than 800 ⁇ ⁇ cm.
  • the electrical resistivity of the molten glass is reliably reduced as compared with the electrical resistivity of the refractory (furnace wall), so that the refractory (furnace wall) is damaged. This is more advantageous in eliminating the fear.
  • the raw material supply start step is performed after the temperature in the glass melting furnace has risen to a temperature at which the glass raw material can be melted (meltable temperature).
  • the glass raw material supplied after the raw material supply start step starts melting immediately after the supply, the components contained in the glass raw material are volatilized and disappear before the raw material is melted. Can be accurately avoided.
  • the air-fired burner which has a significantly lower thermal power than the oxy-fuel burner and has a low contribution in raising the temperature in the furnace, should be stopped after the start of the second heating step. Accordingly, it is possible to prevent the manufacturing cost of the glass article from unduly increasing.
  • the molten glass is heated only by electric heating.
  • the atmosphere in the glass melting furnace is dried as compared with the case where the combustion of the burner is also used. For this reason, it is possible to prevent moisture in the atmosphere from melting into the molten glass, and it is possible to reduce the ⁇ -OH value in the obtained glass article. Thereby, compaction at the time of heating the obtained glass article can be reduced, and a glass article suitable for a glass substrate for a display can be obtained.
  • the present invention when producing glass articles, it is possible to suitably start up a furnace when continuously producing molten glass made of glass having a high melting temperature using a glass melting furnace.
  • FIG. 3 is a cross-sectional plan view illustrating a continuous generation step in the method for manufacturing a glass article according to the embodiment of the present invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view which shows the start-up process in the manufacturing method of the glass article which concerns on embodiment of this invention. It is a vertical side view
  • FIGS. 1 and 2 show an embodiment in which a continuous production step is performed in a glass melting furnace 1 (hereinafter simply referred to as furnace 1).
  • the molten glass 2 stored in the furnace 1 is electrically heated by the electrode 3 while the temperature in the furnace 1 (molten glass) is maintained at an operating temperature (for example, 1450 ° C. to 1550 ° C.). Meanwhile, the alkali-free glass raw material 4 continuously supplied on the surface 2a of the molten glass 2 is sequentially melted to continuously produce new molten glass 2, and the molten glass 2 is caused to flow out of the furnace 1 from the outlet 5. In this continuous generation step, the molten glass 2 is heated only by the electric heating by the electrode 3.
  • the molten glass 2 made of non-alkali glass generated in the continuous generation step is sent to a downstream step including a forming step and the like, and is formed through a process of forming the molten glass 2 in the downstream step and the like.
  • a downstream step including a forming step and the like
  • Glass tubes, glass fibers, etc. Glass tubes, glass fibers, etc.
  • the “alkali-free glass” is a glass that does not substantially contain an alkali component (alkali metal oxide), and specifically means a glass having a weight ratio of the alkali component of 3000 ppm or less.
  • the weight ratio of the alkali component is preferably 1000 ppm or less, more preferably 500 ppm or less, and most preferably 300 ppm or less.
  • the electrical resistivity of the molten glass 2 made of non-alkali glass is less than 800 ⁇ ⁇ cm at 1400 ° C.
  • the furnace 1 used in the present embodiment has a rectangular cross section in plan view.
  • the furnace 1 includes a front wall 1a located at an upstream end in a flow direction T of the alkali-free glass raw material 4 in the furnace 1, a rear wall 1b located at a downstream end, a pair of side walls 1c and 1d, and a ceiling wall. 1e and a bottom wall 1f.
  • the bottom wall 1f on which the electrode 3 is arranged is made of a high electric resistance refractory (for example, high zirconia electroformed refractory brick or dense zircon fired) whose electric resistivity at 1400 ° C. is 800 ⁇ ⁇ cm or more. Bricks).
  • the bottom wall 1f of the present embodiment further includes a highly corrosion-resistant refractory having excellent corrosion resistance (for example, a zirconia-based electroformed refractory brick).
  • the high corrosion resistant refractory is arranged so as to surround the electrode 3, and the high electric resistance refractory is arranged between the high corrosion resistant refractories. More preferably, the high electrical resistance refractory has an electrical resistivity at 1400 ° C. of 1000 ⁇ ⁇ cm or more.
  • the electrical resistivity at 1400 ° C. of the high electrical resistance refractory is 50,000 ⁇ ⁇ cm or less.
  • the high electric resistance refractory may be arranged so as to prevent a current from flowing through the entire bottom wall 1f, and is not limited to the arrangement of the present embodiment.
  • a plurality of (three in the present embodiment) screw feeders 6 for supplying the non-alkali glass raw material 4 into the furnace 1 are arranged in parallel on the front wall 1a. Each screw feeder 6 is inserted into an opening 1aa formed in the front wall 1a without a gap.
  • the alkali-free glass raw material 4 supplied from the screw feeder 6 contains tin oxide as a fining agent.
  • the screw feeder 6 is used to supply the alkali-free glass raw material 4, but a batch charger other than the screw feeder 6 may be used.
  • a vibration feeder As an example of the batch charger, a vibration feeder, a pusher, a blanket charger, or the like may be used. From the viewpoint of improving the hermeticity in the furnace 1, it is preferable to use the screw feeder 6 or the vibration feeder.
  • a plurality of screw feeders 6 are used, but the number of screw feeders 6 may be only one.
  • An outlet 5 for letting out the molten glass 2 is disposed on the rear wall 1b.
  • a burner pair 9 composed of a pair of one air combustion burner 7 and one oxygen combustion burner 8 is arranged.
  • three pairs of the burners are provided on the side wall 1c.
  • Burner pairs 9 are arranged, and two pairs of burner pairs 9 are arranged on the side wall 1d.
  • the air combustion burners 7 and the oxyfuel burners 8 are arranged in pairs, but the numbers of the air combustion burners 7 and the oxyfuel burners 8 may be different. Further, the air combustion burner 7 and the oxyfuel burner 8 may be arranged on the ceiling wall 1e.
  • both the air combustion burner 7 and the oxyfuel burner 8 are in a state where the operation is stopped.
  • the air combustion burner 7 and / or the oxyfuel burner 8 may be operated.
  • the air combustion burner 7 is a burner that mixes and burns gaseous fuel such as natural gas and air.
  • the oxyfuel burner 8 is a burner that mixes and burns gaseous fuel and oxygen.
  • Each of the two burners 7, 8 can inject the flames 7a, 8a from the side wall 1c (side wall 1d) side to the opposing side wall 1d (side wall 1c) side, as shown by a two-dot chain line in FIG. It is.
  • the thermal power of the oxyfuel burner 8 is larger than the thermal power of the air combustion burner 7.
  • the flame 7a injected by the air combustion burner 7 is wider in plan view than the flame 8a injected by the oxyfuel burner 8.
  • the air combustion burner 7 can be removed from the side wall 1c (side wall 1d) in a state where the operation is stopped.
  • the oxyfuel burner 8 may also be removable from the side wall 1c (side wall 1d) in a state where the operation is stopped.
  • the electrode 3 arranged on the bottom wall 1f is formed in a rod shape.
  • the electrode 3 has an advanced position where the electrode 3 has advanced into the furnace 1 from the bottom wall 1f (the position where the electrode 3 is located in FIG. 1) and a retracted position where the electrode 3 has been retracted from the furnace 1 (the electrode 3 has been located in FIG. Position).
  • the electrode 3 is made of, for example, molybdenum.
  • the molten glass 2 is heated by the electrode 3 located at the advanced position and immersed in the molten glass 2 in the furnace 1.
  • the voltage applied to the electrode 3 it is possible to adjust the energy generated by the electrode 3 (thermal energy applied to the molten glass 2).
  • the electrode 3 heats the molten glass 2
  • the alkali-free glass raw material 4 on the surface 2 a of the molten glass 2 is indirectly heated and melted. Thereby, new molten glass 2 is generated sequentially.
  • the molten glass 2 is heated by the rod-shaped electrode 3.
  • the molten glass 2 is applied to each of the pair of side walls 1 c and 1 d.
  • the molten glass 2 may be heated by the arranged plate-shaped electrodes or block-shaped electrodes.
  • start-up process is executed to start up the furnace 1 to a state where the above-described continuous generation process can be executed.
  • a first temperature raising step in which the temperature in the furnace 1 is raised from room temperature (particularly a temperature at which cooling and heating is not performed, for example, 20 ° C. ⁇ 15 ° C.) by the air combustion burner 7; 8 a second temperature raising step (FIG. 4) for raising the temperature in the furnace 1, a raw material supply start step for starting the supply of the alkali-free glass raw material 4 into the furnace 1 (FIG. 5), And an energization heating start step (FIG. 7) for starting the energization heating of the molten glass 2 stored by melting.
  • the electrode 3 is located at the retracted position, and the furnace 1 is placed above the electrode 3. Cover with the first glass plate 10 placed on the bottom wall 1f. Thus, the electrode 3 is protected by the first glass plate 10. The state in which the electrode 3 is covered with the first glass plate 10 continues until the first glass plate 10 is melted with the rise in the temperature in the furnace 1. Thereby, contact between the gas in the furnace 1 and the electrode 3 is prevented, and oxidation of the electrode 3 is avoided as much as possible.
  • the space formed between the first glass plate 10 and the electrode 3 is filled with a large number of glass blocks (not shown) formed in a block shape.
  • the upper part of the electrode 3 is covered with the first glass plate 10, but this is not a limitation.
  • the upper part of the electrode 3 may be covered with cullet.
  • the first glass plate 10 and the cullet it is preferable to use a glass plate and a cullet made of non-alkali glass.
  • the outlet 5 is covered with the second glass plate 11.
  • the outlet 5 and the inside of the furnace 1 are partitioned by the second glass plate 11.
  • the state in which the outlet 5 and the inside of the furnace 1 are partitioned is continued until the second glass plate 11 is melted with the rise in the temperature inside the furnace 1. This prevents gas such as oxygen from flowing between the inside of the furnace 1 and the outlet 5, and oxidizes platinum contained in the outlet 5 as much as possible.
  • the second glass plate 11 a glass plate made of non-alkali glass is preferably used.
  • the upper part of the electrode 3 is covered with the first glass plate 10 and the outlet 5 is covered with the second glass plate 11. Instead, these may be performed at the start of the first temperature raising step.
  • the first temperature raising step is started by operating the air combustion burner 7 and injecting the flame 7a as shown in FIG. .
  • the supply of the alkali-free glass raw material 4 into the furnace 1 has not been started, and the first glass plate 10 and the second glass plate 11 have been removed.
  • the molten glass 2 and the non-alkali glass raw material 4 do not exist in the furnace 1.
  • the second temperature raising step starts from the first temperature raising step.
  • the operation of the air combustion burner 7 is sequentially stopped, and the operation of the oxyfuel burner 8 is sequentially started.
  • the start of the operation of the first oxyfuel burner 8 is the start of the second heating step.
  • the screw feeder 6 is operated to start the supply of the alkali-free glass raw material 4 into the furnace 1, thereby performing a raw material supply start step.
  • the alkali-free glass raw material 4 may be partially or entirely cullet.
  • the raw material supply start step may be performed at the same time as the completion of the switching from the first temperature raising step to the second temperature raising step, as long as the temperature in the furnace 1 has risen to the melting temperature.
  • the raw material supply start step may be performed at any time before the temperature in the furnace 1 rises to the melting temperature.
  • the raw material supply is performed after the temperature in the furnace 1 is raised to the melting temperature.
  • a start step is performed.
  • the alkali-free glass raw material 4 supplied into the furnace 1 is sequentially melted, and the molten glass 2 is stored in the furnace 1. Thereby, the height position of the surface 2 a of the molten glass 2 gradually rises in the furnace 1.
  • a first glass plate 10 partitioning the inside of the furnace 1 from the electrode 3 and a second glass plate 11 partitioning the inside of the furnace 1 from the outlet 5 Melts sequentially as the temperature in the furnace 1 increases.
  • the electric resistance of the refractory constituting each of the furnace walls 1a to 1f is increased.
  • the electrode 3 is moved from the retracted position to the advanced position as shown in FIG. Then, an energization heating start step is performed by applying a voltage to the electrode 3.
  • the temperature inside the furnace 1 is, for example, in the range of 1300 ° C. to 1600 ° C.
  • the electric resistivity of the molten glass becomes lower than the electric resistivity of the refractory means that the electric resistivity of the molten glass at the temperature in the furnace is higher than the electric resistivity of the refractory at the temperature in the furnace. Means low.
  • the furnace 1 In order to maintain the inside temperature, the operation of the oxyfuel burner 8 is sequentially stopped. When the operation of all the oxyfuel burners 8 is stopped, the start-up process is completed. Then, the continuous production process is started in the furnace 1.
  • the temperature in the furnace 1 is raised by the oxyfuel burner 8 after the start of the first temperature raising step in which the temperature in the furnace 1 is raised from room temperature by the air combustion burner 7 in the start-up process.
  • a second heating step is performed.
  • the alkali-free glass raw material 4 supplied after the raw material supply start step can be reliably melted and stored in the furnace 1, so that the energization heating start step can also be performed reliably.
  • the furnace 1 can be suitably started when the molten glass 2 made of non-alkali glass is continuously produced using the furnace 1.
  • the present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects.
  • the present invention can be variously modified without departing from the gist of the present invention.
  • the glass raw material is a non-alkali glass raw material, but other glass raw materials having a high melting temperature may be used.
  • the melting temperature of the glass raw material can be 900 ° C. or higher, preferably 1000 ° C. or higher, more preferably 1100 ° C. or higher.
  • a glass material of aluminosilicate glass or a glass material of soda lime glass can be used.
  • the electrical resistivity of the molten glass at 1400 ° C. is less than 800 ⁇ ⁇ cm, but is not limited thereto.
  • the electrical resistivity of the molten glass at 1400 ° C. can be, for example, 2000 ⁇ ⁇ cm or less, and is preferably less than 800 ⁇ ⁇ cm.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Glass Melting And Manufacturing (AREA)

Abstract

L'invention concerne un procédé de fabrication qui comprend : un processus de formation continue pour, tout en chauffant électriquement un verre fondu (2) placé dans un four (1), faire fondre un matériau de départ en verre exempt d'alcali (4) fourni en continu à celui-ci pour former ainsi en continu du verre fondu frais (2) et, dans le même temps, permettre l'écoulement du verre fondu (2) depuis le four (1) à travers un orifice de sortie (5) ; et un processus de réglage pour régler le four (1) jusqu'à ce que le processus mentionné ci-dessus devienne exécutable, le processus de réglage comprenant une première étape d'augmentation de température pour élever la température dans le four (1) à partir de la température ambiante à l'aide d'un brûleur à combustion d'air (7) et une seconde étape d'augmentation de température pour, après avoir démarré la première étape d'augmentation de température, élever la température dans le four (1) à l'aide d'un brûleur à combustion d'oxygène (8).
PCT/JP2019/024065 2018-06-27 2019-06-18 Procédé de fabrication d'un article en verre WO2020004138A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2020527424A JP7196917B2 (ja) 2018-06-27 2019-06-18 ガラス物品の製造方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018-122157 2018-06-27
JP2018122157 2018-06-27

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WO2020004138A1 true WO2020004138A1 (fr) 2020-01-02

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JP (1) JP7196917B2 (fr)
TW (1) TW202016031A (fr)
WO (1) WO2020004138A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11240727A (ja) * 1998-02-27 1999-09-07 Asahi Glass Co Ltd 溶融ガラスの減圧脱泡装置
JP2010112652A (ja) * 2008-11-07 2010-05-20 Nippon Electric Glass Co Ltd ガスバーナ及び溶融炉の加熱方法
WO2013011837A1 (fr) * 2011-07-15 2013-01-24 日東紡績株式会社 Dispositif de fusion de verre, dispositif de production d'une fibre de verre et procédé de production d'une fibre de verre
JP2013095639A (ja) * 2011-11-01 2013-05-20 Asahi Glass Co Ltd ガラス溶融炉の予備加熱方法とガラス溶融装置およびガラス物品の製造方法
WO2016185976A1 (fr) * 2015-05-18 2016-11-24 日本電気硝子株式会社 Substrat de verre non alcalin

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11240727A (ja) * 1998-02-27 1999-09-07 Asahi Glass Co Ltd 溶融ガラスの減圧脱泡装置
JP2010112652A (ja) * 2008-11-07 2010-05-20 Nippon Electric Glass Co Ltd ガスバーナ及び溶融炉の加熱方法
WO2013011837A1 (fr) * 2011-07-15 2013-01-24 日東紡績株式会社 Dispositif de fusion de verre, dispositif de production d'une fibre de verre et procédé de production d'une fibre de verre
JP2013095639A (ja) * 2011-11-01 2013-05-20 Asahi Glass Co Ltd ガラス溶融炉の予備加熱方法とガラス溶融装置およびガラス物品の製造方法
WO2016185976A1 (fr) * 2015-05-18 2016-11-24 日本電気硝子株式会社 Substrat de verre non alcalin

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JP7196917B2 (ja) 2022-12-27
TW202016031A (zh) 2020-05-01
JPWO2020004138A1 (ja) 2021-07-08

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