Glass melting furnace, glass product manufacturing equipment, and glass product manufacturing method

Abstract

To provide a glass melting furnace capable of enhancing thermal efficiency and obtaining molten glass having suppressed compositional variation.SOLUTION: A glass melting furnace includes upstream and downstream walls facing each other and first and second side walls facing each other. The first side wall has a first burner group; the second side wall has a second burner group; an oxygen combustion burner forms 70% or more of a total combustion heat quantity per hour supplied by the first and second burner groups; when setting a distance from the upstream wall to the downstream wall to L, calling a direction of the L as an extension direction and calling a burner on the most upstream side in the first burner group as a first most upstream burner, the first most upstream burner is arranged at a position to a distance of 0.15 L in the extension direction from the upstream wall; and the first most upstream burner is an air combustion burner.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a glass melting furnace, a glass product manufacturing facility, and a glass product manufacturing method. [Background technology]

[0002] A glass manufacturing facility for producing glass products includes a glass melting furnace, in which glass raw materials are melted to form molten glass.

[0003] Generally, a glass melting furnace has an upstream wall and a downstream wall facing each other, two side walls facing each other, and a top and bottom surface, which define a lower melting section and an upper ceiling section.

[0004] The upstream wall is provided with an inlet for glass raw materials, and the downstream wall is provided with an outlet for molten glass or a passage for transporting the molten glass to another room. In addition, a number of burners are installed on the ceiling side of the side wall to heat and melt the glass in the melting section.

[0005] Burners can be broadly classified into air-fired burners and oxyfuel burners. Air-fired burners use air as the gas mixed with fuel such as natural gas and / or heavy oil, while oxyfuel burners use oxygen as the gas mixed with fuel. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2011 / 136086 Summary of the Invention [Problem to be solved by the invention]

[0007] Oxygen combustion burners have better thermal efficiency than air combustion burners and can reduce the amount of gas used, which helps to reduce CO2 emissions. x It can also reduce emissions of nitrogen oxides.

[0008] However, when all burners in a glass melting furnace are oxygen combustion burners, the concentration of moisture contained in the combustion exhaust gas tends to increase, resulting in a problem in that the amount of moisture contained in the molten glass also increases.

[0009] In particular, some glass manufacturing facilities use platinum components that provide excellent protection against molten glass. When such platinum components come into contact with moisture in molten glass, the moisture decomposes, generating hydrogen and oxygen. Of these, hydrogen can permeate the platinum components and quickly escape from the system. However, oxygen remains in the molten glass, resulting in bubbles remaining in the manufactured glass product.

[0010] In order to address the quality problems of glass products caused by such bubbles, Patent Document 1 proposes arranging oxygen combustion burners and air combustion burners at predetermined positions to reduce the amount of water contained in the molten glass.

[0011] However, the configuration of the glass melting furnace described in Patent Document 1 has a problem in that the efficiency of heat supplied into the glass melting furnace is low, and the amount of fuel used in the burner increases significantly.

[0012] Furthermore, according to the findings of the present inventors, when the burner arrangement as described in Patent Document 1 is adopted, a problem often arises in that a glass product having a desired composition cannot be obtained.

[0013] The present invention has been made in view of the above background, and has an object to provide a glass melting furnace that can significantly improve thermal efficiency and produce molten glass with significantly reduced composition deviation. Another object of the present invention is to provide a glass product manufacturing facility including such a glass melting furnace. Another object of the present invention is to provide a glass product manufacturing method using such a glass melting furnace. [Means for solving the problem]

[0014] The present invention provides a glass melting furnace, a first side wall and a second side wall facing each other; a first group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the first side wall, and a second group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the second side wall; 70% or more of the total combustion heat amount supplied per hour by the first burner group and the second burner group is supplied by the oxygen combustion burners; the first side wall and / or the second side wall are provided with an exhaust port for exhausting combustion exhaust gas to the outside of the system, and the exhaust port closest to the upstream wall is referred to as a specific exhaust port; When the distance from the upstream wall to the downstream wall is L, the direction of L is referred to as the extension direction, and the burner located most upstream in the first burner group is referred to as the first most upstream burner, the first most upstream burner is disposed at a position that is a distance of up to 0.15L from the upstream wall along the extension direction, A glass melting furnace is provided, wherein the first most upstream burner is an air-fired burner.

[0015] The present invention also provides a glass product manufacturing facility, comprising: a glass melting furnace; a molding device; a conveying device connecting the glass melting furnace and the forming device; Equipped with The glass melting furnace is a glass melting furnace having the above-described characteristics, and a manufacturing apparatus is provided.

[0016] Furthermore, the present invention provides a method for producing a glass product, comprising the steps of: A dissolution process; A conveying process; A molding process; and The manufacturing method is provided in which the melting step uses a glass melting furnace having the above-described characteristics. [Effects of the Invention]

[0017] The present invention provides a glass melting furnace that can significantly increase thermal efficiency and produce molten glass with significantly reduced compositional deviation. The present invention also provides a glass product manufacturing facility that includes such a glass melting furnace. Furthermore, the present invention also provides a glass product manufacturing method that uses such a glass melting furnace. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic top view of a glass melting furnace according to one embodiment of the present invention; [Figure 2] 2 is a schematic cross-sectional side view of the glass melting furnace shown in FIG. 1. [Figure 3] FIG. 2 is a schematic top view of another glass melting furnace according to an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional side view of the glass melting furnace shown in FIG. 3. [Figure 5] FIG. 2 is a schematic top view of yet another glass melting furnace according to an embodiment of the present invention. [Figure 6] FIG. 6 is a schematic cross-sectional side view of the glass melting furnace shown in FIG. 5. [Figure 7] 1 is a diagram illustrating a flow of a method for manufacturing a glass product according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment of the present invention will be described below.

[0020] As mentioned above, the configuration of the glass melting furnace described in Patent Document 1 has the problem that the efficiency of heat supplied to the glass melting furnace is low, resulting in a significant increase in fuel consumption. Furthermore, when the burner arrangement described in Patent Document 1 is adopted, a problem often arises in that a glass product having a desired composition cannot be obtained.

[0021] In contrast, in one embodiment of the present invention, a glass melting furnace is provided, a first side wall and a second side wall facing each other; a first group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the first side wall, and a second group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the second side wall; 70% or more of the total combustion heat amount supplied per hour by the first burner group and the second burner group is supplied by the oxygen combustion burners; the first side wall and / or the second side wall are provided with an exhaust port for exhausting combustion exhaust gas to the outside of the system, and the exhaust port closest to the upstream wall is referred to as a specific exhaust port; When the distance from the upstream wall to the downstream wall is L, the direction of L is referred to as the extension direction, and the burner located most upstream in the first burner group is referred to as the first most upstream burner, the first most upstream burner is disposed at a position that is a distance of up to 0.15L from the upstream wall along the extension direction, A glass melting furnace is provided, wherein the first most upstream burner is an air-fired burner.

[0022] A glass melting furnace according to one embodiment of the present invention has exhaust ports in the first side wall and / or the second side wall for exhausting combustion exhaust gas to the outside of the system. The number of exhaust ports provided in the first side wall and the second side wall is not particularly limited, and there may be multiple exhaust ports.

[0023] Here, in the present application, of the exhaust ports provided in the first side wall and the second side wall, the exhaust port located closest to the upstream wall is particularly referred to as a "specific exhaust port."

[0024] For example, if only the first sidewall has exhaust ports, the exhaust port closest to the upstream wall is referred to as the "specific exhaust port." Similarly, if only the second sidewall has exhaust ports, the exhaust port closest to the upstream wall is referred to as the "specific exhaust port."

[0025] Furthermore, when one or more exhaust ports are present in each of the first and second side walls, the exhaust port closest to the upstream wall is referred to as the “specific exhaust port.” In this case, there may be two “specific exhaust ports.”

[0026] In one embodiment of the present invention, 70% or more of the total combustion heat per hour supplied by the first group of burners and the second group of burners is provided by the oxy-fuel burners.

[0027] Generally, oxygen-fuel combustion burners have higher combustion efficiency than air-fuel combustion burners. Therefore, in a glass melting furnace according to one embodiment of the present invention, by providing 70% or more of the total combustion heat per hour from oxygen-fuel combustion burners, the thermal efficiency within the furnace can be significantly improved.

[0028] According to the findings of the present inventors, when an oxygen combustion burner is installed near the inlet for the glass frit, the volatile components in the glass frit are more likely to volatilize due to the high amount of heat supplied by the oxygen combustion burner.

[0029] However, in one embodiment of the present invention, an air-fired burner is used as the most upstream burner (first most upstream burner) in the first burner group, which is located at a distance of up to 0.15 L from the upstream wall along the extension direction.

[0030] The air combustion burner has a lower combustion efficiency than the oxygen combustion burner. Therefore, in one embodiment of the present invention, the heat input to the glass frit can be significantly suppressed. As a result, the volatile components contained in the glass frit are less likely to volatilize.

[0031] Due to these effects, when the glass melting furnace according to one embodiment of the present invention is used, the composition of the molten glass can be made closer to the desired composition, and thus glass products having the desired composition can be produced.

[0032] Due to the above effects, one embodiment of the present invention can provide a glass melting furnace that can significantly increase thermal efficiency and can produce molten glass with significantly reduced deviation in composition.

[0033] Here, in the present application, the distance L from the upstream wall to the downstream wall is defined as the distance from the most downstream position of the upstream wall to the most upstream position of the downstream wall.

[0034] Furthermore, the distance L between the upstream wall and the first most upstream burner is defined as the distance from the most downstream position of the upstream wall to the first most upstream burner along the "extension direction."

[0035] (Glass melting furnace according to one embodiment of the present invention) Hereinafter, a glass melting furnace according to an embodiment of the present invention will be described in more detail with reference to the drawings.

[0036] Fig. 1 shows a schematic top view of a glass melting furnace according to one embodiment of the present invention, and Fig. 2 shows a schematic side cross-sectional view of the glass melting furnace according to one embodiment of the present invention.

[0037] As shown in Figures 1 and 2, a glass melting furnace according to one embodiment of the present invention (hereinafter referred to as the "first melting furnace" 100) has an upstream wall 110 and a downstream wall 120 facing each other, and a first side wall 130A and a second side wall 130B facing each other.

[0038] The upstream wall 110 is provided with an inlet 112 for glass raw material MA, and the downstream wall 120 is provided with an outlet 122 for molten glass MG.

[0039] As mentioned above, the distance between the upstream wall 110 and the downstream wall 120 is represented by L, and the direction of the distance L is the "drawing direction."

[0040] The first melting furnace 100 further has a top surface 192 and a bottom surface 194. Therefore, the upstream wall 110, the downstream wall 120, the first side wall 130A, the second side wall 130B, the top surface 192, and the bottom surface 194 define a lower melting section BC and an upper ceiling section UC.

[0041] Melting section BC contains molten glass MG. Ceiling section UC is provided with a plurality of combustion burners (described in detail below), a first exhaust port 150A and a second exhaust port 150B.

[0042] A first burner group 140A including a plurality of burners 1A to 8A is arranged on the ceiling portion UC side of the first side wall 130A. Similarly, a second burner group 140B including a plurality of burners 1B to 8B is arranged on the ceiling portion UC side of the second side wall 130B.

[0043] The burners 1A to 8A of the first burner group 140A and the burners 1B to 8B of the second burner group 140B each have the role of injecting flames generated when the mixed gas is burned into the first melting furnace 100 to melt the glass raw material MA and heat the molten glass MG.

[0044] Of the first burner group 140A, burner 1A is the burner located on the most upstream side, and the reference numerals of the subsequent burners increase sequentially toward the downstream side. Therefore, when the first burner group 140A is composed of n burners (n is an integer of 2 or more), the most downstream burner is represented by the reference numeral nA. The same applies to each burner in the second burner group 140B.

[0045] The first exhaust port 150A is provided on the ceiling portion UC side of the first side wall 130A, and the second exhaust port 150B is provided on the ceiling portion UC side of the second side wall 130B. Two or more first exhaust ports 150A and two or more second exhaust ports 150B may be provided. Alternatively, one of the first exhaust port 150A and the second exhaust port 150B may be omitted.

[0046] Of the first exhaust port 150A and the second exhaust port 150B, the one closest to the upstream wall 110 is referred to as the "specific exhaust port." In the example shown in FIGS. 1 and 2, one each of the first exhaust port 150A and the second exhaust port 150B is installed. Furthermore, the first exhaust port 150A and the second exhaust port 150B are positioned so as to face each other in a top view. Therefore, in this case, both the first exhaust port 150A and the second exhaust port 150B are "specific exhaust ports."

[0047] Hereinafter, in the first melting furnace 100, the upstream side of the specific exhaust port will be referred to as the "first section (PA)" and the downstream side of the specific exhaust port will be referred to as the "second section (PB)."

[0048] The burners 1A-8A included in the first burner group 140A are divided into burners 1A-3A arranged in the "first section PA" and burners 4A-8A arranged in the "second section PB." Similarly, the burners 1B-8B included in the second burner group 140B are divided into burners 1B-3B arranged in the "first section PA" and burners 4B-8B arranged in the "second section PB."

[0049] 1 and 2, the first melting furnace 100 has a partition wall 160 in the melting section BC. The partition wall 160 is arranged to extend parallel to the upstream wall 110 and the downstream wall 120. However, the bottom of the partition wall 160 is open, so that the molten glass MG can flow from the upstream side (the upstream wall 110 side) through the partition wall 160 to the downstream side (the downstream wall 120 side) along the extension direction of the first melting furnace 100 (the X direction in FIGS. 1 and 2).

[0050] The molten glass MG in the melting part BC can be homogenized by providing such a partition wall 160. However, the partition wall 160 may be omitted.

[0051] The first melting furnace 100 having such a configuration is used as follows.

[0052] First, glass raw material MA is supplied from the inlet 112 of the upstream wall 110 to the melting section BC.

[0053] The glass frit MA is heated by the flames of the burners 1A to 8A and 1B to 8B included in the first burner group 140A and the second burner group 140B, respectively, to form a molten glass MG.

[0054] The molten glass MG is contained in the melting section BC and flows downstream along the drawing direction. A partition wall 160 is provided in the melting section BC. Therefore, the molten glass MG passes through the bottom of the partition wall 160 and flows downstream. During this process, the movement of "foreign matter," such as unmelted components, which may affect the uniformity of the glass product being manufactured, is prevented. Therefore, the molten glass MG is homogenized by passing through the partition wall 160.

[0055] Thereafter, the molten glass MG that has reached the downstream wall 120 is discharged from the outlet 122 and transported to the next device in the glass manufacturing facility.

[0056] The combustion exhaust gases generated by the combustion in each of the burners 1A to 8A and 1B to 8B are discharged through a first exhaust port 150A and a second exhaust port 150B.

[0057] Here, in the first melting furnace 100, 70% or more of the total combustion heat amount supplied per hour by the first burner group 140A and the second burner group 140B is supplied by the oxygen-fuel combustion burners. In other words, the contribution of the air-fuel combustion burners is limited to a maximum of 30% of the total combustion heat amount.

[0058] By selecting the total amount of combustion heat supplied by the oxygen combustion burners in this manner, the thermal efficiency within the first melting furnace 100 can be significantly improved compared to the conventional case.

[0059] In the first melting furnace 100, the first burner 1A (hereinafter also referred to as the "first most upstream burner 1A") located most upstream in the first burner group 140A is an air-fired burner. The first most upstream burner 1A is disposed at a distance of 0.15L or less from the upstream wall 110 along the extension direction of the first melting furnace 100.

[0060] When the first most upstream burner 1A is selected and arranged in this manner, as described above, the heat input to the glass frit MA can be significantly suppressed, and as a result, the volatile components contained in the glass frit MA are less likely to volatilize.

[0061] Therefore, in the first melting furnace 100, the composition of the molten glass can be made closer to the desired composition, and as a result, glass products with the desired composition can be produced.

[0062] Furthermore, in the first melting furnace 100, the first burner 1B (hereinafter also referred to as the "second most upstream burner 1B") located most upstream in the second burner group 140B is also an air-fired burner. The second most upstream burner 1B is disposed at a distance of 0.15L or less from the upstream wall 110 along the extension direction of the first melting furnace 100.

[0063] In this case, it becomes possible to further suppress the volatilization of the volatile components contained in the glass raw material MA.

[0064] (Explanation of each part) Next, each part constituting the glass melting furnace according to one embodiment of the present invention will be described in more detail.

[0065] For clarity, the following description will be given taking the first melting furnace 100 as an example, and the reference numerals shown in Figures 1 and 2 will be used to represent the various parts.

[0066] (First melting furnace 100) The first melting furnace 100 is applied as one device included in a glass manufacturing facility. Typically, the glass manufacturing facility has a glass melting furnace, a forming device, and a conveying device connecting the two.

[0067] In the first melting furnace 100, the width between the first side wall 130A and the second side wall 130B is represented by W (see FIG. 1). Here, the width W is defined as the distance L from the innermost position of the first side wall 130A to the innermost position of the second side wall 130B.

[0068] In the first melting furnace 100, L / W is in the range of 2 to 5, for example.

[0069] (First exhaust port 150A, second exhaust port 150B) As described above, the exhaust port located most upstream of the first exhaust port 150A and the second exhaust port 150B is referred to as the specific exhaust port. However, in the example shown in Figures 1 and 2, the first exhaust port 150A and the second exhaust port 150B are located opposite each other, and either one may be referred to as the specific exhaust port.

[0070] The specific exhaust port may be located at a position 0.3 L to 0.7 L from the upstream wall 110 along the extension direction of the first melting furnace 100.

[0071] In addition, when there is one first exhaust outlet 150A and one second exhaust outlet 150B, the position of the second exhaust outlet 150B may be shifted by 0 to 0.2L from the first exhaust outlet 150A in the extension direction of the first melting furnace 100 when viewed from above.

[0072] (First burner group 140A, second burner group 140B) As described above, in the first melting furnace 100, 70% or more of the total combustion heat amount per hour supplied by the first burner group 140A and the second burner group 140B is supplied by the oxygen combustion burners.

[0073] By selecting the total amount of combustion heat supplied by the oxygen combustion burners in this manner, the thermal efficiency within the first melting furnace 100 can be significantly improved compared to the conventional case.

[0074] Furthermore, 30% to 80% of the combustion heat per hour in the first section PA may be supplied by the oxygen combustion burner.

[0075] Additionally or alternatively, 90% to 100% of the combustion heat per hour in the second section PB may be supplied by the oxygen combustion burner.

[0076] 1 and 2, in the first burner group 140A, the first most upstream burner 1A is disposed upstream of the specific exhaust port. Similarly, in the second burner group 140B, the second most upstream burner 1B is disposed upstream of the specific exhaust port.

[0077] In this configuration, the frit MA introduced into the first melting furnace 100 passes through the designated exhaust port after being melted to a certain extent. This significantly reduces the possibility that the frit MA will be discharged through the designated exhaust port before being melted. In particular, if the frit MA is discharged through the exhaust port before being melted, the exhaust port may be clogged or the composition of the glass product may be deviated. However, the configurations shown in Figures 1 and 2 can reduce such problems.

[0078] 1, the burners 1A-8A included in the first burner group 140A and the burners 1B-8B included in the second burner group 140B are arranged to face each other in a top view of the first melting furnace 100. However, this is merely an example, and the relative positions of the burners 1A-8A included in the first burner group 140A and the burners 1B-8B included in the second burner group 140B are not particularly limited. For example, the burners 1A-8A and the burners 1B-8B may be arranged to be offset from each other in the extension direction of the first melting furnace 100.

[0079] Furthermore, the burners 1A to 8A included in the first burner group 140A do not necessarily need to be arranged at equal intervals. For example, the burners 1A to 8A may be arranged at unequal intervals along the extension direction of the first melting furnace 100. The same applies to the second burner group 140B.

[0080] Furthermore, the number of burners included in the first burner group 140A and the second burner group 140B is not particularly limited. For example, the first burner group 140A and the second burner group 140B may each include less than eight burners or nine or more burners.

[0081] Furthermore, in the first burner group 140A, the number of burners included in the first section PA and the second section PB is not particularly limited. The same is true for the second burner group 140B.

[0082] As described above, the first most upstream burner 1A in the first burner group 140A is disposed at a distance of 0.15 L or less from the upstream wall 110 along the extension direction of the first melting furnace 100. This distance is preferably 0.1 L or less.

[0083] The second most upstream burner 1B in the second burner group 140B is preferably located at a distance of 0.15 L or less from the upstream wall 110 along the extension direction of the first melting furnace 100. More preferably, this distance is 0.1 L or less.

[0084] (Another glass melting furnace according to one embodiment of the present invention) Next, with reference to FIGS. 3 and 4, another glass melting furnace according to an embodiment of the present invention will be described.

[0085] Fig. 3 shows a schematic top view of another glass melting furnace (hereinafter referred to as "second melting furnace") according to an embodiment of the present invention, and Fig. 4 shows a schematic side view of the second melting furnace shown in Fig. 3.

[0086] 3 and 4, the second melting furnace 200 has a configuration similar to that of the first melting furnace 100. For example, the second melting furnace 200 has an upstream wall 210, a downstream wall 220, a first side wall 230A, a second side wall 230B, a first group of burners 240A, and a second group of burners 240B.

[0087] However, the second melting furnace 200 generally differs from the first melting furnace 100 in the arrangement of the first exhaust port 250A and the second exhaust port 250B.

[0088] That is, in the second melting furnace 200, the first exhaust port 250A and the second exhaust port 250B are both located upstream of the first burner group 240A and the second burner group 240B. The first exhaust port 250A and the second exhaust port 250B are located so as to face each other in a top view of the second melting furnace 200. Therefore, the first exhaust port 250A and the second exhaust port 250B are both "specified exhaust ports."

[0089] As a result of the above arrangement, in the second melting furnace 200, no burners are arranged upstream of a specific exhaust port (e.g., the first exhaust port 250A), i.e., in the first section PA, and all burners are arranged downstream of the specific exhaust port, i.e., in the second section PB.

[0090] Here, in the second melting furnace 200 as well, 70% or more of the total combustion heat amount per hour supplied by the first burner group 240A and the second burner group 240B is supplied by the oxygen combustion burners.

[0091] Also in second melting furnace 200, first most upstream burner 1A in first burner group 240A is an air-fired burner, and second most upstream burner 1B in second burner group 240B is an air-fired burner. Furthermore, first most upstream burner 1A in first burner group 240A is disposed at a distance of 0.15L or less from upstream wall 210 along the extension direction of second melting furnace 200, where L is the distance from upstream wall 210 to downstream wall 220.

[0092] 3, the second most upstream burner 1B in the second burner group 240B may be disposed at a distance of 0.15 L or less from the upstream wall 210 along the extension direction of the second melting furnace 200.

[0093] It will be apparent to those skilled in the art that the second melting furnace 200 having such a configuration can also provide the same effects as the first melting furnace 100.

[0094] That is, in the second melting furnace 200 as well, the thermal efficiency within the second melting furnace 200 can be significantly improved compared to the conventional case.

[0095] Furthermore, in the second melting furnace 200, the heat input to the glass frit MA is significantly suppressed, and the volatile components contained in the glass frit MA are less likely to volatilize, which makes it possible to produce glass products with the desired composition.

[0096] (Yet another glass melting furnace according to one embodiment of the present invention) Next, with reference to FIGS. 5 and 6, a further glass melting furnace according to an embodiment of the present invention will be described.

[0097] Fig. 5 shows a schematic top view of yet another glass melting furnace (hereinafter referred to as "third melting furnace") according to an embodiment of the present invention, and Fig. 6 shows a schematic side view of the third melting furnace shown in Fig. 5.

[0098] 5 and 6, the third melting furnace 300 has a configuration similar to that of the first melting furnace 100. For example, the third melting furnace 300 has an upstream wall 310, a downstream wall 320, a first side wall 330A, a second side wall 330B, a first group of burners 340A, and a second group of burners 340B.

[0099] However, the third melting furnace 300 generally differs from the first melting furnace 100 described above in that it further includes a chamber 380 downstream of the downstream wall 320 .

[0100] A narrowed passage 382 is disposed between the downstream wall 320 and the chamber 380. Note that no burner is provided on the side wall of the chamber 380.

[0101] By providing such a chamber 380, the temperature of the molten glass MG can be made uniform.

[0102] In the third melting furnace 300, the first burner group 340A has a total of five burners (first burner 1A to fifth burner 4A). Similarly, the second burner group 340B has a total of five burners (first burner 1B to fifth burner 4B).

[0103] Furthermore, in the third melting furnace 300, the first exhaust port 350A is arranged between the first burner 1A and the second burner 2A included in the first burner group 340A, and the second exhaust port 350B is arranged between the first burner 1B and the second burner 2B included in the second burner group 340B.

[0104] The first exhaust port 350A and the second exhaust port 350B are arranged to face each other when viewed from above the third melting furnace 300. Therefore, both the first exhaust port 350A and the second exhaust port 350B are "specified exhaust ports."

[0105] As a result of the above arrangement, in the third melting furnace 300, only the first burner 1A (i.e., the first most upstream burner 1A) of the first burner group 340A is arranged upstream of a specific exhaust port (e.g., the first exhaust port 350A), i.e., in the first section PA, and the second burner 2A to the fourth burner 4A are arranged downstream of the specific exhaust port, i.e., in the second section PB. Similarly, in the second burner group 340B, only the first burner 1B (i.e., the second most upstream burner 1B) is arranged in the first section PA, and the second burner 2B to the fourth burner 4B are arranged in the second section PB.

[0106] Here, also in the third melting furnace 300, 70% or more of the total combustion heat amount per hour supplied by the first burner group 340A and the second burner group 340B is supplied by the oxygen combustion burners.

[0107] In the first section PA, 30% to 80% of the combustion amount per hour may be produced by the oxygen combustion burner, and in the second section PB, 90% to 100% of the combustion amount per hour may be produced by the oxygen combustion burner.

[0108] In the third melting furnace 300, the first most upstream burner 1A in the first burner group 340A is an air-fired burner, and the second most upstream burner 1B in the second burner group 340B is also an air-fired burner. Furthermore, when the distance from the upstream wall 310 to the downstream wall 320 is L, the first most upstream burner 1A in the first burner group 340A is positioned at a distance of 0.15L or less from the upstream wall 310 along the extension direction of the third melting furnace 300.

[0109] 5, the second most upstream burner 1B in the second burner group 340B may be disposed at a distance of 0.15 L or less from the upstream wall 310 along the extension direction of the third melting furnace 300.

[0110] It will be apparent to those skilled in the art that the third melting furnace 300 having such a configuration can also provide the same effects as the first melting furnace 100 and the second melting furnace 200.

[0111] That is, in the third melting furnace 300 as well, the thermal efficiency within the third melting furnace 300 can be significantly improved compared to the conventional case.

[0112] Furthermore, in the third melting furnace 300, the heat input to the glass frit MA is significantly suppressed, and the volatile components contained in the glass frit MA are less likely to volatilize, which makes it possible to produce glass products with the desired composition.

[0113] The glass melting furnace according to one embodiment of the present invention has been described above using the first melting furnace 100 to the third melting furnace 300 as examples. However, the glass melting furnace according to one embodiment of the present invention is not limited to the above-described embodiment. It will be apparent to those skilled in the art that various other practical embodiments can be envisioned.

[0114] For example, in the above-mentioned first melting furnace 100 to third melting furnace 300, an air-fired burner is selected as the first burner 1A in the first burner group in order to suppress the volatilization of the volatile components contained in the glass frit MA.

[0115] However, in the glass melting furnace according to one embodiment of the present invention, a small auxiliary oxygen combustion burner or the like may be installed upstream of the first burner 1A, as long as the evaporation of the volatile components can be suppressed.

[0116] In other words, in this application, the terms "first burner," "first most upstream burner," and "second most upstream burner" do not exclude the existence of a "sub" burner upstream thereof, as long as the effects of the present invention are achieved.

[0117] (Method of manufacturing a glass product according to one embodiment of the present invention) Next, a method for manufacturing a glass product according to one embodiment of the present invention will be described with reference to FIG.

[0118] FIG. 7 shows a schematic flow of a method for manufacturing a glass product according to one embodiment of the present invention.

[0119] As shown in FIG. 7, the method for manufacturing a glass product according to one embodiment of the present invention (hereinafter referred to as the "first method") includes the following steps: A melting step (step S110) of melting glass raw materials to form molten glass; a conveying step (step S120) of conveying the molten glass; A forming step (step S130) of forming the molten glass; It has.

[0120] Each step will be described below.

[0121] (Step S110) First, glass raw materials are melted in a glass melting furnace to form molten glass. The composition of the glass raw materials is not particularly limited.

[0122] The glass melting furnace used is a glass melting furnace according to one embodiment of the present invention. For example, glass melting furnaces such as the first melting furnace 100 to the third melting furnace 300 described above may be used.

[0123] For example, when the first melting furnace 100 is used as the glass melting furnace, glass frit MA supplied through the inlet 112 of the upstream wall 110 is heated by the flames of the burners 1A-8A and 1B-8B included in the first burner group 140A and the second burner group 140B. This forms molten glass MG. The formed molten glass is discharged from the outlet 122.

[0124] When the glass melting furnace according to the embodiment of the present invention is used as the glass melting furnace, 70% or more of the total combustion heat amount supplied per hour by the first burner group and the second burner group is supplied by the oxygen combustion burners, thereby significantly improving the thermal efficiency in the glass melting furnace.

[0125] Furthermore, when the glass melting furnace according to the embodiment of the present invention is used, the heat input at the glass frit MA inlet 112 side can be significantly reduced, thereby significantly reducing the volatilization of volatile components in the glass frit MA. As a result, the composition of the molten glass can be made closer to the desired composition, and glass products with the desired composition can be produced.

[0126] (Process S120) The formed molten glass is then transported to a forming device via a transport device.

[0127] (Step S130) The transported molten glass is then shaped in a shaping device to form a glass ribbon, which is then annealed to produce a glass product, which may then be cut to a desired size, if desired.

[0128] The glass product produced may be alkali-free glass.

[0129] Alkali-free glass is expressed as mass % based on oxides, SiO2: 54-73% Al2O3: 10-23% B2O3: 0.1~12% MgO: 0-12% CaO: 0-15% SrO: 0 to 16% BaO: 0-15% Contains MgO + CaO + SrO + BaO: 8 to 26% may be.

[0130] In the case of alkali-free glass having such a composition, B2O3 corresponds to the volatile component.

[0131] In addition, the glass products manufactured have a β-OH of 0.3 mm. -1 ~0.45mm -1 may be in the range of

[0132] Here, β-OH is an index representing the amount of water in the glass, and the larger this value is, the more water is contained in the glass. [Example]

[0133] Examples of the present invention will be described below, in which Examples 1 to 3 are examples, and Examples 11 to 15 are comparative examples.

[0134] (Example 1) A glass melting furnace such as the first melting furnace 100 described above was used to melt glass raw materials.

[0135] The glass raw materials were alkali-free glasses having the following composition, expressed in mass % on an oxide basis: SiO2: 54-73%, Al2O3: 10-23%, B2O3: 0.1~12%, MgO: 0-12%, CaO: 0-15%, SrO: 0 to 16%, BaO: 0-15%.

[0136] The total content of MgO, CaO, SrO and BaO is 8 to 26%.

[0137] Of these, B2O3 is a component that is relatively easy to volatilize.

[0138] In the glass melting furnace, the first burner group and the second burner group each consist of a total of eight burners.

[0139] Furthermore, one first exhaust port is installed on the first side wall, and one second exhaust port is installed on the second side wall. When viewed from above, the first exhaust port and the second exhaust port are positioned to face each other. Therefore, both the first exhaust port and the second exhaust port are designated exhaust ports.

[0140] The first exhaust port and the second exhaust port were installed at a distance of 0.55 L from the upstream wall along the elongation direction of the glass melting furnace.

[0141] As shown in Figures 1 and 2, the first section PA had six burners, 1A to 3A and 1B to 3B, and the second section PB had ten burners, 4A to 8A and 4B to 8B.

[0142] Of the first burner group, only the most upstream first burner 1A was an air-fuel combustion burner. Also, of the second burner group, only the most upstream second burner 1B was an air-fuel combustion burner. The remaining burners were oxygen-fuel combustion burners.

[0143] The distance between the upstream wall and the most upstream air-fired burner (burner 1A) in the first burner group along the extension direction of the glass melting furnace was 0.1 L. The distance between the upstream wall and the most upstream air-fired burner (burner 1B) in the second burner group along the extension direction of the glass melting furnace was also 0.1 L.

[0144] The contribution rate of the oxygen combustion burners to the total heat supply is 88%. In the first section PA, the contribution rate of the oxygen combustion burners to the heat supply is 71%. Similarly, in the second section PB, the contribution rate of the oxygen combustion burners to the heat supply is 100%.

[0145] (Example 2) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0146] However, in this Example 2, the first burner 1A and the eighth burner 8A of the first burner group were air-fuel combustion burners. Similarly, the first burner 1B and the eighth burner 8B of the second burner group were air-fuel combustion burners. The remaining burners were oxygen-fuel combustion burners.

[0147] The contribution rate of the oxygen combustion burners to the total heat supply was set to 82%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 71%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 90%.

[0148] (Example 3) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0149] However, in this Example 3, among the first burner group, the first burner 1A and the second burner 2A were air-fuel combustion burners. Similarly, among the second burner group, the first burner 1B and the second burner 2B were air-fuel combustion burners. The remaining burners were oxygen-fuel combustion burners.

[0150] The contribution rate of the oxygen combustion burners to the total heat supply was set to 73%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 36%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 100%.

[0151] (Example 11) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0152] However, in this Example 11, all of the burners included in the first burner group were oxygen-fuel combustion burners, and similarly, all of the burners included in the second burner group were oxygen-fuel combustion burners.

[0153] The contribution rate of the oxygen combustion burners to the total heat supply is 100%. Also, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA is 100%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB is 100%.

[0154] (Example 12) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0155] However, in this example 12, the third burner 3A in the first burner group was an air-fuel combustion burner. Similarly, the third burner 3B in the second burner group was an air-fuel combustion burner. The remaining burners were oxygen-fuel combustion burners.

[0156] The distance between the upstream wall and the most upstream air-fired burner (burner 3A) in the first burner group along the elongation direction of the glass melting furnace was 0.25 L. Similarly, the distance between the upstream wall and the most upstream air-fired burner (burner 3B) in the second burner group along the elongation direction of the glass melting furnace was 0.25 L.

[0157] The contribution rate of the oxygen combustion burners to the total heat supply was set to 85%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 71%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 100%.

[0158] (Example 13) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0159] However, in this example 13, the eighth burner 8A in the first burner group was an air-fuel combustion burner. Similarly, the eighth burner 8B in the second burner group was an air-fuel combustion burner. The remaining burners were oxygen-fuel combustion burners.

[0160] The distance between the upstream wall and the most upstream air-fired burner (burner 8A) in the first burner group along the elongation direction of the glass melting furnace was 0.9 L. Similarly, the distance between the upstream wall and the most upstream air-fired burner (burner 8B) in the second burner group along the elongation direction of the glass melting furnace was 0.9 L.

[0161] The contribution rate of the oxygen combustion burners to the total heat supply was set to 94%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 100%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 90%.

[0162] (Example 14) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0163] However, in this example 14, of the first burner group, the first burner 1A and the fifth burner 5A to the eighth burner 8A were air-fuel combustion burners. Similarly, of the second burner group, the first burner 1B and the fifth burner 5B to the eighth burner 8B were air-fuel combustion burners. The remaining burners were oxygen-fuel combustion burners.

[0164] The distance between the most upstream air-fired burner (burner 1A) in the first burner group and the upstream wall along the elongation direction of the glass melting furnace was 0.1 L. The distance between the most upstream air-fired burner (burner 1B) in the second burner group and the upstream wall along the elongation direction of the glass melting furnace was 0.1 L.

[0165] The contribution rate of the oxygen combustion burners to the total heat supply was set to 44%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 71%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 24%.

[0166] (Example 15) Using the same glass melting furnace as in Example 1, glass raw materials were melted.

[0167] However, in this example 15, of the first burner group, the first burner 1A to the second burner 2A and the fifth burner 5A to the eighth burner 8A were air-fuel combustion burners. Similarly, of the second burner group, the first burner 1B to the second burner 2B and the fifth burner 5B to the eighth burner 8B were air-fuel combustion burners. The remaining burners were oxygen-fuel combustion burners.

[0168] The distance between the most upstream air-fired burner (burner 1A) in the first burner group and the upstream wall along the elongation direction of the glass melting furnace was 0.1 L. The distance between the most upstream air-fired burner (burner 1B) in the second burner group and the upstream wall along the elongation direction of the glass melting furnace was 0.1 L.

[0169] The contribution rate of the oxygen combustion burners to the total heat supply was set to 29%. In addition, the contribution rate of the oxygen combustion burners to the heat supply in the first section PA was set to 36%. Similarly, the contribution rate of the oxygen combustion burners to the heat supply in the second section PB was set to 24%.

[0170] Table 1 below summarizes the burner configurations of the glass melting furnaces used in each example.

[0171] [Table 1] (evaluation) In each example, the amount of fuel used per hour during operation of the glass melting furnace was evaluated. Also, in each example, the volatility of volatile components in the molten glass was evaluated. Furthermore, the β-OH content in the molten glass obtained in each example was evaluated.

[0172] The volatility of the volatile components was evaluated as follows.

[0173] The surface temperature of the molten glass was measured near the tip of the flame of the first burner 1A in the first burner group. If the surface temperature exceeded 1650°C, it was determined that the volatile components were likely to volatilize, and if the surface temperature was 1650°C or less, it was determined that the volatile components were unlikely to volatilize. A two-color radiation thermometer was used to measure the temperature.

[0174] The β-OH was evaluated as follows.

[0175] First, the moisture concentration in the gas after combustion was calculated based on the fuel and gas composition burned by each burner. Next, the moisture concentration distribution in the atmosphere inside the melting chamber was calculated, taking into account that the gas after combustion flows toward the first and second exhaust ports. Next, the amount of moisture ultimately diffused into the molten glass was calculated based on the moisture concentration distribution and the average flow velocity of the molten glass, and this was converted into the β-OH contained in the glass after production.

[0176] Table 2 below summarizes the results obtained in each example.

[0177] [Table 2] In Table 2, the "fuel consumption" column shows the standard value for the fuel consumption in Example 11. That is, the "fuel consumption" in each example is shown as a percentage, with the fuel consumption in Example 11 set at 100.

[0178] In Table 2, in the column "Volatilization suppression effect," ◯ indicates that the volatile component is unlikely to volatilize, and × indicates that the volatile component is likely to volatilize.

[0179] The results show that in Example 11, in which all burners were oxygen combustion burners, the amount of fuel used was kept low. However, it was also found that the β-OH content in the glass was the highest in Example 11. It was also found that the volatile components in the glass raw materials were easily volatilized in Example 11.

[0180] Also in Examples 12 and 13, it was found that the volatile components in the glass raw materials were easily volatilized.

[0181] In addition, in Examples 14 and 15, although the volatilization of volatile components tended to be suppressed, the amount of fuel used increased and the efficiency decreased.

[0182] In contrast, it was found that volatilization of volatile components was less likely to occur in Examples 1 to 3. Furthermore, there was a tendency for the amount of fuel used to be significantly reduced in Examples 1 to 3. Furthermore, β-OH was also significantly reduced in Examples 1 to 3.

[0183] Thus, it was confirmed that the thermal efficiency can be significantly improved by making the contribution rate of the oxygen combustion burners to the total combustion heat amount 70% or more.Furthermore, it was confirmed that the evaporation of volatile components can be significantly suppressed by using air combustion burners as the first most upstream burner 1A and the second most upstream burner 1B and setting the distance from the upstream wall to these burners 1A and 1B along the extension direction to 0.15 L or less. [Explanation of symbols]

[0184] 1A~8A burner 1B~8B burner 100 Glass melting furnace (first melting furnace) 110 Upstream wall 112 Inlet 120 Downstream Wall 122 Outlet 130A first side wall 130B second side wall 140A First Burner Group 140B Second Burner Group 150A First exhaust port 150B Secondary Exhaust Port 160 Partition Wall 192 Top surface 194 bottom 200 Glass melting furnace (second melting furnace) 210 Upstream wall 212 Inlet 220 Downstream Wall 222 Outlet 230A First Side Wall 230B Second side wall 240A First Burner Group 240B Second Burner Group 250A First Exhaust Port 250B Secondary Exhaust Port 260 Partition Wall 292 Top surface 294 bottom 300 Glass Melting Furnace (Third Melting Furnace) 310 Upstream wall 312 Inlet 320 Downstream Wall 322 Outlet 330A first side wall 330B Second side wall 340A First Burner Group 340B Second Burner Group 350A First Exhaust Port 350B Secondary Exhaust Port 380 rooms 382 Narrow tract 392 Top surface 394 bottom BC melting section MA glass raw materials MG molten glass PA Section 1 PB Section 2 UC ceiling

Claims

1. A glass melting furnace, the nozzle has an upstream wall and a downstream wall opposed to each other, and a first side wall and a second side wall opposed to each other; a first group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the first side wall, and a second group of burners including oxygen-fuel combustion burners and air-fuel combustion burners is disposed on the second side wall; 70% or more of the total combustion heat amount per hour supplied by the first burner group and the second burner group is supplied by the oxygen combustion burners, the first side wall and / or the second side wall are provided with an exhaust port for exhausting combustion exhaust gas to the outside of the system, and the exhaust port closest to the upstream wall is referred to as a specific exhaust port; a distance from the upstream wall to the downstream wall is designated as L, the direction of L is designated as an extension direction, and the burner located most upstream in the first burner group is designated as a first most upstream burner, the first most upstream burner is disposed at a position that is a distance of 0.15L from the upstream wall along the extension direction, A glass melting furnace, wherein the first most upstream burner is an air-fired burner.

2. The glass melting furnace according to claim 1 , wherein the first most upstream burner is disposed upstream of the specific exhaust port.

3. When the burner located most upstream in the second burner group is referred to as a second most upstream burner, the second most upstream burner is disposed at a position that is a distance of up to 0.15L from the upstream wall along the extension direction, 3. The glass melting furnace according to claim 1, wherein the second most upstream burner is an air-fired burner.

4. The glass melting furnace according to claim 3 , wherein the second most upstream burner is disposed upstream of the specific exhaust port.

5. 5. The glass melting furnace according to claim 1, wherein the specific exhaust port is disposed at a position 0.3 L to 0.7 L from the upstream wall along the extension direction.

6. the first sidewall is provided with one or more first exhaust ports; 6. The glass melting furnace according to claim 1, wherein the second side wall is provided with one or more second exhaust ports.

7. the first exhaust port and the second exhaust port are each present in one; 7. The glass melting furnace according to claim 6, wherein the second exhaust port is disposed at a position shifted by 0 to 0.2 L from the first exhaust port in the extension direction.

8. 8. The glass melting furnace according to claim 1, wherein when the distance between the first side wall and the second side wall is a width W, L / W=2 to 5.

9. a partition wall for guiding molten glass between the upstream wall and the downstream wall; 9. The glass melting furnace according to claim 1, wherein the molten glass flows through the bottom of the glass melting furnace when passing through the partition wall.

10. A glass product manufacturing facility, a glass melting furnace; a molding device; a conveying device connecting the glass melting furnace and the forming device; Equipped with The glass melting furnace according to claim 1 , wherein the glass melting furnace is a manufacturing apparatus.

11. A method for manufacturing a glass product, comprising: A dissolution process; A conveying process; A molding process; and A manufacturing method, wherein the melting step uses a glass melting furnace according to any one of claims 1 to 9.

12. The glass product is made of alkali-free glass, The alkali-free glass contains, in mass % on an oxide basis, Yes ２ :54~73% <h2 style=";text-align:left;direction:ltr">Al<h2 style=";text-align:left;direction:ltr"> ２ <h2 style=";text-align:left;direction:ltr"> O<h2 style=";text-align:left;direction:ltr"> ３ <h2 style=";text-align:left;direction:ltr"> :15~233% B ２ O ３ :0.1~12% MgO: 0 to 12% CaO: 0 to 15% SrO: 0 to 16% BaO: 0 to 15% Contains MgO+CaO+SrO+BaO: 8-26% The method according to claim 11, wherein

13. The glass product has a β-OH content of 0.3 mm. －１ ~0.45mm －１ The method according to claim 11 or 12, wherein the range is

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