Electric heating device and method for high-generation large-tonnage substrate glass kiln

Abstract

An electric heating device and method for a high-generation large-tonnage substrate glass kiln, relating to the field of arrangement of electric heating structures of high-generation large-tonnage substrate glass kilns. In order to solve the problem of insufficient melting in front zones of high-generation large-tonnage substrate glass kilns, the present application designs an electric heating structure combining tin oxide electrodes stacked on sides with bottom-insertion type molybdenum electrodes, then feeds a proper amount of gas, and calculates the energy consumption of glass melting and the energy in gas and electricity under the current extraction amount, so as to further calculate the overall thermal efficiency of the kiln, thereby developing the novel electric heating device and method satisfying high-generation substrate glass kilns having large material feeding amounts. Said device and method can solve the problems such as insufficient melting and instable convection in front zones of high-generation large-tonnage substrate glass kilns.

Description

Electric heating device and method for high-generation large-tonnage substrate glass furnace Technical Field

[0001] The present invention relates to the field of electric heating structure arrangement of high-generation and large-tonnage substrate glass furnaces, and in particular to an electric heating device and method for high-generation and large-tonnage substrate glass furnaces. Background Art

[0002] From the traditional color cathode ray tube industry to the current flat-panel display industry, glass has always played a key role as a key component in display devices. Glass not only serves as the frame and carrier of the entire display device, but also as an optical element. As the upper and lower substrates of flat-panel displays, glass requires sophisticated microscopic semiconductor processing techniques to meet the melting capacity and convection stability of the front zone of the furnace for high-generation, large-tonnage substrate glass. During the manufacturing process of substrate glass, the glass batch is first fed smoothly and stably into the furnace feed port through a feeding system. Within the furnace, it is melted, clarified, and homogenized to provide qualified, homogenous glass liquid for the next process. The glass liquid melted in the melting furnace is alkali-free high-aluminum borosilicate glass, and this glass product is primarily used as substrate glass for flat-panel displays.

[0003] As the feed volume of high-generation substrate glass increases, the insufficient melting capacity of the front zone of the kiln and the stability of the kiln convection circulation have become key problems that need to be solved urgently. Insufficient melting in the front zone of the kiln will lead to a large number of defects such as bubbles and stones in the substrate glass products, seriously affecting production efficiency. Technical issues

[0004] The present invention provides a high-generation large-tonnage substrate glass furnace electric heating device and method to solve the problem of insufficient melting capacity in the pre-melting front zone of the substrate glass furnace caused by large material input, and provides a strong guarantee for the efficient melting and convection stability of large-tonnage substrate glass batch materials. Technical Solutions

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An electric heating device for a high-generation, large-tonnage substrate glass furnace, comprising: a bottom tank wall, a front tank wall, a rear tank wall, a left tank wall, a right tank wall, a feeding port, a liquid flow hole, tin oxide electrode bricks, a bottom-inserted molybdenum electrode, and a lifting adjustment mechanism; the bottom-inserted molybdenum electrode is a molybdenum electrode treated by a multi-element co-infiltration process;

[0007] The front pool wall, rear pool wall, right pool wall and left pool wall are arranged on the bottom pool wall, the two ends of the front pool wall are connected to the two ends of the rear pool wall through the left pool wall and the right pool wall respectively, the feeding port is arranged on the front pool wall, the flow hole is arranged on the rear pool wall, a number of tin oxide electrode bricks are arranged on the left pool wall and the right pool wall, the intervals between the several tin oxide electrode bricks are equal, a number of bottom-plugged molybdenum electrodes are arranged on the bottom pool wall, a part of the tin oxide electrode bricks on the left pool wall protrudes to the outside of the left pool wall, a part of the tin oxide electrode bricks on the right pool wall protrudes to the outside of the right pool wall, and a lifting adjustment mechanism is installed at the bottom of the protruding part of the tin oxide electrode brick.

[0008] Furthermore, two feeding ports are provided on the front pool wall.

[0009] Furthermore, eight tin oxide electrode bricks with the same spacing are set on the left side of the pool wall, and eight tin oxide electrode bricks with the same spacing are set on the right side of the pool wall.

[0010] Furthermore, the position of the tin oxide electrode brick on the left side of the pool wall corresponds to the position of the tin oxide electrode brick on the right side of the pool wall.

[0011] Furthermore, the distance between the two tin oxide electrode bricks at corresponding positions on the left pool wall and the right pool wall is greater than twice the width of the tin oxide electrode brick.

[0012] Furthermore, four bottom-inserted molybdenum electrodes are provided, and the four bottom-inserted molybdenum electrodes are parallel to each other.

[0013] Furthermore, two bottom-inserted molybdenum electrodes are arranged near the left side of the pool wall, and another two bottom-inserted molybdenum electrodes are arranged near the right side of the pool wall.

[0014] Furthermore, the distance between the top of the tin oxide electrode brick and the top of the left pool wall is greater than 70 mm, and the distance between the top of the tin oxide electrode brick and the top of the right pool wall is greater than 70 mm.

[0015] Furthermore, the bottom-inserted molybdenum electrode remains flush with the inner surface of the bottom pool wall.

[0016] A method for an electric heating device for a high-generation, large-tonnage substrate glass furnace, based on the electric heating device, comprises the following steps:

[0017] Two feeding ports are opened on the front wall of the pool, and a liquid flow hole is opened on the rear wall of the pool;

[0018] Install 8 tin oxide electrode bricks at equal intervals on the left side of the pool wall, and install 8 tin oxide electrode bricks at equal intervals at corresponding positions on the right side of the pool wall, with the distance between two tin oxide electrode bricks at corresponding positions being 2300mm~2320mm; install a lifting adjustment mechanism at the bottom of each of the above tin oxide electrode bricks;

[0019] A bottom-inserted molybdenum electrode is installed on the bottom pool wall. Before installation, the bottom-inserted molybdenum electrode is treated by a multi-element co-penetration process to form a high-temperature anti-oxidation coating on the surface of the bottom-inserted molybdenum electrode.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects:

[0021] The present invention provides an electric heating device for a high-generation, large-tonnage substrate glass furnace. The bottom pool wall, front pool wall, rear pool wall and side pool wall form a semi-closed structure. A feeding port is arranged on the front pool wall, a liquid flow port is arranged on the rear pool wall, tin oxide electrode bricks with equal intervals are arranged on the side pool walls, a bottom-inserted molybdenum electrode is arranged on the bottom pool wall, and a jacking adjustment mechanism is installed at the bottom of the tin oxide electrode brick. The present invention aims to solve the problems of insufficient melting capacity and unstable convection in the front zone of the pre-melting furnace for high-tonnage substrate glass with large feeding amount by calculating the comprehensive thermal efficiency of the furnace, rationally arranging the side-stacked tin oxide electrode structure and rationally designing the bottom-inserted molybdenum electrode at the bottom of the furnace, thereby solving the problem of insufficient melting capacity in the front zone of the pre-melting furnace for substrate glass caused by large feeding amount, and providing a strong guarantee for the efficient melting and stable convection of large-tonnage substrate glass batch materials.

[0022] Furthermore, the present invention has four molybdenum electrodes arranged in the structure, the melting point of the molybdenum electrodes is greater than 2420°C, the density is greater than 10.2g / cm3, and the surface current density is between 0.7A / cm2 and 1.0A / cm2, so that the device can maintain a longer operating life.

[0023] Furthermore, the present invention provides corresponding 8 tin oxide electrode bricks with the same spacing on the left and right side pool walls, which can ensure that the device maintains a long operating life.

[0024] Furthermore, the distance between the top of the tin oxide electrode brick of the present invention and the top of the left and right side pool walls is greater than 70 mm, which can ensure that the tin oxide electrode brick is covered by the normal glass liquid surface and inhibit high-temperature oxidation and volatilization of the electrode. Beneficial effects

[0025] The present invention provides a method for an electric heating device for a high-generation, large-tonnage substrate glass furnace. After a bottom-inserted molybdenum electrode is treated by a multi-element co-infiltration process, the bottom-inserted molybdenum electrode is installed on the bottom pool wall. This method can form a high-temperature anti-oxidation coating on the surface of the molybdenum electrode, solving the problem that the molybdenum electrode cannot be used in an oxidizing atmosphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a front view of an electric heating device for a high-generation, large-tonnage substrate glass furnace;

[0027] FIG2 is a top view of an electric heating device for a high-generation, large-tonnage substrate glass furnace;

[0028] Figure 3 is a side view of the electric heating device of a high-generation, large-tonnage substrate glass furnace.

[0029] Among them, 1. Tin oxide electrode bricks; 2. Left side pool wall; 3. Rear pool wall; 4. Burner bricks of lance; 5. Side breast wall; 6. Front pool wall; 7. Liquid level line; 8. Feeding port; 9. Liquid flow hole; 10. Bottom-inserted molybdenum electrode; 11. Lifting adjustment mechanism; 12. Right side pool wall. Modes for Carrying Out the Invention

[0030] Hereinafter, only certain exemplary embodiments are briefly described, and the described embodiments may be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0033] In the present invention, unless otherwise expressly specified or limited, terms such as "install," "connect," "connected," and "fixed" should be understood in a broad sense. For example, the terms "install," "connect," "connect," and "fixed" may refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections, or communication; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0034] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0035] Example 1

[0036] As shown in Figures 1 and 2, a new type of electric heating device for a high-generation, large-tonnage substrate glass furnace has a front pool wall 6, a rear pool wall 3, a left pool wall 2, and a right pool wall 12 arranged on the bottom pool wall, which together form a semi-enclosed rectangular structure. Two feeding ports 8 are provided on the front pool wall 6, a liquid flow hole 9 is provided on the rear pool wall 3, and side-stacked tin oxide electrode bricks 1 are provided on the left pool wall 2 and the right pool wall 12. The bottom of the tin oxide electrode brick 1 is designed with a lifting adjustment mechanism 11, and a bottom-inserted molybdenum electrode 10 is designed on the bottom pool wall.

[0037] Specifically, the position of the tin oxide electrode brick 1 on the left side of the pool wall 2 corresponds to the position of the tin oxide electrode brick 1 on the right side of the pool wall 12;

[0038] Specifically, the distance between the bottom-inserted molybdenum electrode 10 and the inner side of the front pool wall 6 is 620mm~630mm, and the spacing between the bottom-inserted molybdenum electrodes 10 on both sides is 960mm~980mm, which can solve the problem of insufficient melting capacity in the front zone of the glass furnace for pre-melting of the feeding substrate;

[0039] Specifically, four bottom-inserted molybdenum electrodes 10 are provided on the bottom pool wall, and the bottom-inserted molybdenum electrodes 10 are parallel to each other;

[0040] Specifically, the selected bottom-inserted molybdenum electrode 10 has a melting point greater than 2420°C, a density greater than 10.2g / cm3, and a surface current density between 0.7 and 1.0A / cm2, and can maintain a long operating life;

[0041] Specifically, the bottom-inserted molybdenum electrode 10 selected needs to be prepared with a high-temperature anti-oxidation coating on the surface of the pure molybdenum electrode using a multi-element co-penetration process before use, and the outermost surface of the coating is a SiO2 coating; specifically, the melting point of the tin oxide electrode brick 1 is greater than 1630°C, the density is greater than 6.5g / cm3, and the current density is required to be less than 0.1 A / cm2, which can maintain a long operating life;

[0042] Specifically, a total of 8 pairs of corresponding tin oxide electrode bricks 1 are designed on the left pool wall 2 and the right pool wall 12. The spacing between each pair of tin oxide electrode bricks 1 is between 2300mm and 2320mm, which can ensure that the voltage between each pair of electrodes is less than 1100V. The spacing between each pair of tin oxide electrode bricks 1 is required to be greater than 2 times the width of the tin oxide electrode brick 1.

[0043] Specifically, the tin oxide electrode brick 1 is required to be covered by a normal glass liquid surface to inhibit the high-temperature oxidation and volatilization of the electrode. Therefore, the liquid surface height is required to be greater than the height of the top of the tin oxide electrode brick 1 by more than 70mm.

[0044] Specifically, in order to solve the melting problem in the pre-melting front zone of the kiln under large charge, the present invention designs two pairs of bottom-inserted molybdenum electrodes 10 in the pre-melting front zone of the kiln. The upper surface of the molybdenum electrode is flush with the bottom of the pool, which is used to improve the melting problem at the bottom of the material mountain.

[0045] The present invention provides a method for an electric heating device for a high-generation large-tonnage substrate glass furnace, comprising the following steps:

[0046] Two feeding ports (8) are provided on the front pool wall (6), and a liquid flow hole (9) is provided on the rear pool wall;

[0047] Eight tin oxide electrode bricks (1) are evenly spaced on the left side of the pool wall (2), and eight tin oxide electrode bricks (1) are evenly spaced at corresponding positions on the right side of the pool wall (12), with the distance between two tin oxide electrode bricks (1) at corresponding positions being 2300 mm to 2320 mm; a lifting adjustment mechanism (11) is installed at the bottom of each of the above tin oxide electrode bricks (1);

[0048] A bottom-inserted molybdenum electrode (10) is installed on the bottom pool wall. Before installation, the bottom-inserted molybdenum electrode (10) is treated by a multi-element co-infiltration process to form a high-temperature anti-oxidation coating on the surface of the bottom-inserted molybdenum electrode (10).

[0049] The present invention focuses on the arrangement of electrodes. The structure in Figure 3, together with the side breast wall 5 and the lance burner brick 4, highlights that the kiln is a gas-electric hybrid kiln. Since molybdenum electrodes are usually used in reducing atmospheres and are easily oxidized to form MoO3 and volatilize in an oxidizing atmosphere, the present invention uses a multi-element co-penetration process to prepare a high-temperature anti-oxidation coating on the surface of the molybdenum electrode when the molybdenum electrode is put into use, to prevent severe oxidation and volatilization when the glass does not cover the molybdenum electrode during the liquid level rising process. The molybdenum electrode selected in this structure needs to be coated with a high-temperature anti-oxidation coating on the surface of the pure molybdenum electrode using a multi-element co-penetration process before use, and the outermost surface of the coating is a SiO2 coating.

[0050] The present invention can have different combinations of gas-to-electricity ratios when calculating the comprehensive thermal efficiency of the kiln to ensure that the comprehensive thermal efficiency of the kiln is:

[0051] Table 1 Comprehensive thermal efficiency of the kiln at different gas-to-electricity ratios

[0052] Tin oxide electrode power / KWMolybdenum electrode power / KWElectric calorific value (kcal / kj)Burning volume m3 / hGas calorific value (kcal / m3)Total heat kcalOutput kg / hUnit glass melting energy consumption KJKiln thermal efficiency%1000300860100810019280001250228339%1100320860110810021122001250228336%1200360860120810023136001250228333%1250380860130810024548001250228331%

[0053] The present invention is a new type of electric heating structure for a high-generation and large-tonnage substrate glass furnace. First, a simulation analysis is carried out on the problems of insufficient melting in the pre-melting front zone and unstable convection of high-generation substrate glass under large tonnage and large feed rate. Then, by designing different comprehensive amounts of electricity and gas, the comprehensive thermal efficiency of the furnace is calculated to be between 30% and 40%. The side-stacked tin oxide electrode structure is reasonably arranged. At the same time, a bottom-inserted molybdenum electrode is scientifically and rationally designed at the bottom of the pre-melting zone of the furnace, and a layer of high-temperature anti-oxidation coating is prepared on the surface of the molybdenum electrode by a multi-element co-penetration method, which solves the problem that the molybdenum electrode cannot be used in an oxidizing atmosphere. At the same time, the designed safe upper limit of the current density of the tin oxide electrode and the molybdenum electrode ensures the long-term and stable operation of the electrode, solves the problem of insufficient melting capacity in the pre-melting front zone of the substrate glass furnace caused by large feed rate, and provides a strong guarantee for the efficient melting and convection stability of large-tonnage substrate glass batch materials.

[0054] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the embodiments disclosed above are merely illustrative in all respects and are not exclusive. All modifications within the scope of the present invention or equivalent to the scope of the present invention are intended to be encompassed by the present invention.

Claims

1. A high-generation large-tonnage substrate glass furnace electric heating device, characterized in that: include: A bottom pool wall, a front pool wall (6), a rear pool wall (3), a left pool wall (2), a right pool wall (12), a feeding port (8), a liquid flow hole (9), a tin oxide electrode brick (1), a bottom-inserted molybdenum electrode (10) and a lifting adjustment mechanism (11); the bottom-inserted molybdenum electrode (10) is a molybdenum electrode treated by a multi-element co-penetration process; A front pool wall (6), a rear pool wall (3), a right pool wall (12) and a left pool wall (2) are arranged on the bottom pool wall, two ends of the front pool wall (6) are connected to two ends of the rear pool wall (3) through the left pool wall (2) and the right pool wall (12), respectively, a feeding port (8) is arranged on the front pool wall (6), a liquid flow hole (9) is arranged on the rear pool wall (3), a plurality of tin oxide electrode bricks (1) are arranged on the left pool wall (2) and the right pool wall (12), the intervals between the plurality of tin oxide electrode bricks (1) are equal, a plurality of bottom-inserted molybdenum electrodes (10) are arranged on the bottom pool wall, a portion of the tin oxide electrode bricks (1) on the left pool wall (2) protrudes outwardly of the left pool wall (2), a portion of the tin oxide electrode bricks (1) on the right pool wall (12) protrudes outwardly of the right pool wall (12), and a lifting adjustment mechanism (11) is installed at the bottom of the protruding portion of the tin oxide electrode brick (1).

2. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 1 is characterized in that: Two feeding ports (8) are provided on the front pool wall (6).

3. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 1 is characterized in that: Eight tin oxide electrode bricks (1) are arranged at the same interval on the left side of the pool wall (2), and eight tin oxide electrode bricks (1) are arranged at the same interval on the right side of the pool wall (12).

4. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 1 is characterized in that: The position of the tin oxide electrode brick (1) on the left side of the pool wall (2) corresponds to the position of the tin oxide electrode brick (1) on the right side of the pool wall (12).

5. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 4 is characterized in that: The distance between two tin oxide electrode bricks (1) at corresponding positions on the left pool wall (2) and the right pool wall (12) is greater than twice the width of the tin oxide electrode brick (1).

6. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 1 is characterized in that: Four bottom-inserted molybdenum electrodes (10) are provided, and the four bottom-inserted molybdenum electrodes (10) are parallel to each other.

7. The electric heating device for a high-generation, large-tonnage substrate glass furnace according to claim 6 is characterized in that: Two bottom-inserted molybdenum electrodes (10) are arranged near the left side pool wall (2), and another two bottom-inserted molybdenum electrodes (10) are arranged near the right side pool wall (12).

8. The high-generation large-tonnage substrate glass electric heating device according to claim 1 is characterized in that: The distance between the top of the tin oxide electrode brick (1) and the top of the left pool wall (2) is greater than 70 mm, and the distance between the top of the tin oxide electrode brick (1) and the top of the right pool wall (2) is greater than 70 mm.

9. The high-generation large-tonnage substrate glass electric heating device according to claim 1, characterized in that: The bottom-inserted molybdenum electrode (10) is kept flush with the inner surface of the bottom pool wall.

10. A method for an electric heating device for a high-generation large-tonnage substrate glass furnace, based on the electric heating device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Two feeding ports (8) are provided on the front pool wall (6), and a liquid flow hole (9) is provided on the rear pool wall; Eight tin oxide electrode bricks (1) are evenly spaced on the left side of the pool wall (2), and eight tin oxide electrode bricks (1) are evenly spaced at corresponding positions on the right side of the pool wall (12), wherein the distance between two tin oxide electrode bricks (1) at corresponding positions is 2300 mm to 2320 mm; and a lifting adjustment mechanism (11) is installed at the bottom of each of the above tin oxide electrode bricks (1); A bottom-inserted molybdenum electrode (10) is installed on the bottom pool wall. Before installation, the bottom-inserted molybdenum electrode (10) is treated by a multi-element co-penetration process to form a high-temperature anti-oxidation coating on the surface of the bottom-inserted molybdenum electrode (10).

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