JPH07300318A - Glass melting furnace - Google Patents

Glass melting furnace

Info

Publication number
JPH07300318A
JPH07300318A JP11596694A JP11596694A JPH07300318A JP H07300318 A JPH07300318 A JP H07300318A JP 11596694 A JP11596694 A JP 11596694A JP 11596694 A JP11596694 A JP 11596694A JP H07300318 A JPH07300318 A JP H07300318A
Authority
JP
Japan
Prior art keywords
glass
electrodes
current
electrode
melting furnace
Prior art date
Legal status (The legal status 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 status listed.)
Pending
Application number
JP11596694A
Other languages
Japanese (ja)
Inventor
Shinji Kawachi
伸治 川地
Katsumi Inada
勝美 稲田
Toshio Nakamura
利夫 中村
Hirokazu Takeuchi
宏和 竹内
Kazuya Noguchi
和也 野口
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Electric Glass Co Ltd
Original Assignee
Nippon Electric Glass Co Ltd
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 Nippon Electric Glass Co Ltd filed Critical Nippon Electric Glass Co Ltd
Priority to JP11596694A priority Critical patent/JPH07300318A/en
Publication of JPH07300318A publication Critical patent/JPH07300318A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B5/00Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
    • C03B5/16Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
    • C03B5/163Electrochemical treatments, e.g. to prevent bubbling or to create bubbles
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B5/00Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
    • C03B5/02Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating
    • C03B5/027Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating by passing an electric current between electrodes immersed in the glass bath, i.e. by direct resistance heating

Landscapes

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

Abstract

PURPOSE:To prevent reduction and precipitation of a metallic oxide to be readily reduced, to suppress foaming of a component to be easily expanded and to obtain high-quality glass, by connecting each of a pair of electrodes in a glass melting furnace to an earth in such a way that the direction of an electric current flowing from the earths to the electrodes is fixed. CONSTITUTION:A glass melting furnace 1 has a glass raw material feed opening 3, an outlet 4 and an overflow part 5, 12 pairs of current-carrying heating electrodes 6 from a transformer 7 are installed on the bottom of the furnace. A connecting line 8 between the electrodes 6 and the transformer 7 is connected through current rectifiers 9, variable resistances 10 and variable reactors 11 to earths E. In the case where the reduction of a plus ion of a metal oxide becomes a problem in glass in the melting furnace 1, the earths are connected through the current rectifiers 9 to the electrodes so that only a positive electric current flows from the earths E to the electrodes 6 to prevent reduction and precipitation. In the case where the oxidation of a minus ion as an oxygen ion becomes a problem, the earths are connected through the current rectifiers 9 to the electrodes so that only a negative current flows from the earths E to the electrodes 6 to prevent oxidation.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、還元され易い金属酸化
物を含むガラス或は発泡し易い成分を含有するガラス
を、電極により直接通電加熱するガラス溶融炉に関す
る。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass melting furnace in which a glass containing a metal oxide which is easily reduced or a glass containing a component which easily foams is directly heated by an electrode.

【0002】[0002]

【従来の技術】ガラス溶融炉において、電極による直接
通電加熱は、熱効率が良い、ガラス原料の飛散が少ない
等の理由から、年々その利用が増加してきている。
2. Description of the Related Art In a glass melting furnace, direct current heating by an electrode has been increasingly used year by year because of its high thermal efficiency and small scattering of glass raw materials.

【0003】[0003]

【発明が解決しようとする課題】しかしながら、鉛、ヒ
素、アンチモニー等の還元され易いプラスの金属イオン
(Pb2+、As3+、Sb3+)を含むガラスを電極を用い
て直接通電により加熱溶融する場合には、これらの金属
酸化物が電極の配設部所において還元されて、金属とな
って析出する。本来、これらの金属イオンは、ガラス成
分の一部を構成し、清澄剤の作用を有するが、これが金
属となって析出することは、原料費の上昇、清澄作用の
阻害を招くだけでなく、析出した金属異物が電極を侵食
したり、ガラス溶融炉の底面耐火物を侵食して炉の寿命
を短くし、更に製品中にも流出して重大なガラス欠陥と
なる。同様に例えば、酸素がマイナスイオン(O2-)と
して存在するガラスを電極を用いて直接通電により加熱
溶融する場合には、電極で電子を放出し酸素分子となり
泡を発生させる。発生した酸素泡が電極や他の金属部品
を侵食したり、ガラス溶融炉を形成している接液耐火物
を侵食して炉の寿命を短くし、更に製品中にも流出して
重大なガラス欠陥となる。かかる金属異物の析出を防ぐ
方法としては、電極に直流の正極を接続して金属イオン
が還元されるのを防ぐ方法や加熱用電流として超低周波
交流を用いる方法などが提案されており、また、酸素泡
の発生を防ぐ方法としては、電極に直流の負極を接続し
て酸素イオンの電極での電子の放出を防ぐ方法や、加熱
用電極として高周波交流を用いる方法等が提案されてい
るが、電極に直流を印加するには直流安定化電源が、ま
た、加熱用電流として超低周波交流や高周波交流を用い
るには特殊なトランスが必要となり、特に多数の電極を
配設するような大型のガラス溶融炉においては、これら
の特別な付帯設備も大型化するため極めて高価なものと
なる。
However, glass containing positive metal ions (Pb 2+ , As 3+ , Sb 3+ ) that are easily reduced, such as lead, arsenic, and antimony, is heated by direct current application using an electrode. In the case of melting, these metal oxides are reduced at the place where the electrode is provided and are deposited as metal. Originally, these metal ions constitute a part of the glass component, and have the action of a fining agent, but the precipitation of this as a metal not only leads to an increase in raw material costs and inhibition of the fining action, Precipitated metal foreign matter erodes the electrodes and erodes the bottom refractory of the glass melting furnace to shorten the life of the furnace, and also flows into the product to cause a serious glass defect. Similarly, for example, in the case where glass in which oxygen exists as negative ions (O 2− ) is heated and melted by directly energizing using an electrode, electrons are emitted at the electrode to become oxygen molecules and generate bubbles. The generated oxygen bubbles erode the electrodes and other metal parts, and erode the wetted refractories forming the glass melting furnace, shortening the life of the furnace and further spilling into the product, causing serious glass. It becomes a defect. As a method of preventing the precipitation of such metal foreign matter, a method of connecting a DC positive electrode to the electrode to prevent metal ions from being reduced, a method of using an ultra-low frequency AC as a heating current, and the like have been proposed. As a method of preventing the generation of oxygen bubbles, a method of connecting a negative electrode of direct current to the electrode to prevent the emission of electrons at the electrode of oxygen ions, a method of using high-frequency alternating current as a heating electrode, etc. have been proposed. , A DC stabilized power supply is required to apply DC to the electrodes, and a special transformer is required to use ultra-low frequency AC or high frequency AC as the heating current. In such a glass melting furnace, these special incidental facilities also become large in size, which makes them extremely expensive.

【0004】そこで、本考案の目的は、PbO、As2
3 、Sb23 等の還元され易い金属酸化物を含むガ
ラス、或は酸素がイオン(O2-)として存在する発泡し
易い成分を含有するガラスを、電極によって溶融するに
あたり、高価な付帯設備を用いなくてもガラス中の金属
酸化物を還元析出させることなく、また酸素泡等を発泡
させることなく直接通電加熱することができるガラス溶
融炉を提供することである。
Therefore, the purpose of the present invention is to provide PbO, As 2
O 3, Sb 2 O 3 or the like reduced glass containing prone metal oxide, or oxygen glass containing blowing susceptible component is present as an ion (O 2-), Upon melting by the electrode, expensive It is an object of the present invention to provide a glass melting furnace which can be directly energized and heated without reducing and precipitating a metal oxide in glass and without foaming oxygen bubbles and the like without using auxiliary equipment.

【0005】[0005]

【課題を解決するための手段】本発明は、上記の課題お
よび目的に鑑みてなされたもので、溶融炉内に配設され
た電極対の各々とそれに接続されたアースとが、アース
から電極に流れる電流の方向を一定とするように電流整
流器を介して接続されてなることを特徴とするガラス溶
融炉である。
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems and objects, and each of the electrode pairs disposed in the melting furnace and the ground connected thereto are connected from the ground to the electrodes. The glass melting furnace is characterized in that it is connected via a current rectifier so that the direction of the current flowing through the glass is constant.

【0006】具体的には、溶融炉内のガラスにおいて、
金属酸化物等のプラスイオンの還元が問題になり易い場
合には、電極対の各々とアースとが、アースから電極に
正電流のみが流れるように電流整流器を介して接続さ
れ、また、酸素イオンのようにマイナスイオンの酸化が
問題になり易いガラスの場合には、電極対の各々とアー
スとが、アースから電極に負電流のみが流れるように電
流整流器を介して接続されてなることを特徴とする。
[0006] Specifically, in the glass in the melting furnace,
When the reduction of positive ions such as metal oxides is likely to be a problem, each electrode pair and the ground are connected via a current rectifier so that only a positive current flows from the ground to the electrodes, and oxygen ions are also used. In the case of glass in which the oxidation of negative ions is likely to be a problem, as described above, each pair of electrodes and the ground are connected through a current rectifier so that only a negative current flows from the ground to the electrodes. And

【0007】[0007]

【作用】電極対間に交流が印加されると、各々の電極は
正極になる場合と負極になる場合とを交互に繰り返す。
本発明のガラス溶融炉によれば、アースから電極に正電
流のみが流れるように電流整流器を介在させている場合
にはこの電流整流器により、電極が正極になっている場
合、大部分の正電流は電極の表面から溶融ガラスを通り
他方の電極に直接流れ、一部の正電流が溶融ガラスを通
りアースを経由し電流整流器を通って他方の電極に接続
されたトランスへ流れる二通りの流れ方をし、逆に電極
が負極になっている場合には、負電流は電極の表面から
溶融ガラスを通り他方の電極に直接流れるのみで、アー
スを経由し電流整流器を通って他方の電極のトランスへ
は流れない。従って、電極の表面には、正電流が負電流
よりも多く供給されることになり、その結果、電極の表
面では、正電流、即ち+電荷の作用により、Pb2+、A
3+、Sb3+等の金属イオンが還元されず、金属化する
のを防ぐ。さらに、溶融ガラスや耐火物が関係する電気
化学的な現象で電極の表面に−電荷が発生したときに
も、電流整流器を通じて速やかにアースに−電荷が放出
されるため、金属イオンを還元する−電荷が電極表面に
蓄積することがない。また、電流整流器の方向を逆にし
てアースから電極に負電流のみが流れるように電流整流
器を介在させる場合にも正負が逆になるだけで同様の作
用となり、電極の表面では負電流が正電流よりも多く供
給されることになり、その結果、電極の表面では、負電
流、即ち、−電荷の作用により、O2-等のマイナスイオ
ンが酸化されず発泡を防ぐ。本発明においては、溶融ガ
ラスとアースが完全に絶縁された状態ではなく、電流整
流器を介在させることにより、電極表面で正電流と負電
流のバランスが崩れる程度の漏洩電流が、溶融ガラスと
アースの間に流れなければならない。通常、運転中の溶
融炉においては、溶融ガラスとアースの間の抵抗値は数
百Ω程度以下であるため、本発明の作用に関して全く支
障はなく、また、漏洩電流の電流値も非常に小さいもの
であるので安全上の問題も全くない。電流整流器を流れ
る電流値は、電流整流器と直列に接続された可変抵抗器
及び可変リアクトルにより適切な値を設定できるように
してある。可変リアクトルは、電極対間の直接通電交流
に対しては可変抵抗器と同様の抵抗要素となり、電流整
流器を流れる電流値を制御するが、直流に対しては抵抗
値がほぼ0となるので、先に述べた電極表面に発生した
電荷をアースへ放出する過程においては抵抗要素となら
ない。尚、アースに漏洩電流を流すことになる溶融炉の
接液耐火物においては、前記金属イオンが還元され金属
となって析出したり、マイナスイオンが酸化されて発泡
したりするが、これらは非常に大きな面積を持つ接液耐
火物の表面全体に分散されて起こるため局所的には殆ど
無視できる程度であり、また、この部分の溶融ガラスは
流動性が乏しいためガラス製品への金属異物や泡の混入
を避けることができる。
When an alternating current is applied between the pair of electrodes, each of the electrodes alternately becomes positive and negative.
According to the glass melting furnace of the present invention, when the current rectifier is interposed so that only the positive current flows from the ground to the electrode, the current rectifier allows most of the positive current to flow when the electrode is positive. Flows directly from the surface of the electrode through the molten glass to the other electrode, and some positive current flows through the molten glass, through the ground, through the current rectifier, and into the transformer connected to the other electrode. On the contrary, when the electrode is the negative electrode, the negative current only flows directly from the surface of the electrode to the other electrode through the molten glass, and passes through the ground through the current rectifier to the transformer of the other electrode. Does not flow to. Therefore, the positive current is supplied to the surface of the electrode more than the negative current, and as a result, Pb 2+ , A
Prevents metal ions such as s 3+ and Sb 3+ from being reduced and metallized. Furthermore, when an electric charge is generated on the surface of the electrode due to an electrochemical phenomenon involving molten glass or refractory, the electric charge is promptly released to the ground through the current rectifier, and thus the metal ion is reduced. No charge accumulates on the electrode surface. Also, when the direction of the current rectifier is reversed and the current rectifier is interposed so that only the negative current flows from the ground to the electrode, the same effect will be obtained only by reversing the positive and negative. As a result, negative ions such as O 2 − are not oxidized on the surface of the electrode due to the action of a negative current, that is, −charge, to prevent foaming. In the present invention, the molten glass and the ground are not completely insulated, but by interposing a current rectifier, a leakage current of such a degree that the balance between the positive current and the negative current on the surface of the electrode is broken is generated between the molten glass and the ground. Must flow in between. Usually, in the melting furnace during operation, the resistance value between the molten glass and the ground is several hundreds Ω or less, so there is no problem with the operation of the present invention, and the current value of the leakage current is also very small. Since it is a thing, there is no safety problem at all. The current value flowing through the current rectifier can be set to an appropriate value by a variable resistor and a variable reactor connected in series with the current rectifier. The variable reactor serves as a resistance element similar to a variable resistor for direct energization alternating current between the electrode pair and controls the current value flowing through the current rectifier, but since the resistance value is almost 0 for direct current, It does not serve as a resistance element in the process of discharging the electric charge generated on the electrode surface to the ground as described above. In the wetted refractory of the melting furnace that causes a leakage current to flow to the earth, the metal ions are reduced and deposited as metal, or the negative ions are oxidized and foam, but these are extremely Since it occurs because it is dispersed over the entire surface of the wetted refractory having a large area, it is almost negligible locally, and since the molten glass in this part has poor fluidity, metallic foreign matter and bubbles to glass products Can be avoided.

【0008】[0008]

【実施例】以下実施例に基づいて本発明のガラス溶融炉
について説明する。
EXAMPLES The glass melting furnace of the present invention will be described below based on examples.

【0009】図1は本発明にかかるガラス溶融炉の説明
図であり、アースから電極に正電流のみが流れるように
電流整流器を介在させている場合を示している。
FIG. 1 is an explanatory view of a glass melting furnace according to the present invention, and shows a case where a current rectifier is interposed so that only a positive current flows from an earth to an electrode.

【0010】ガラス溶融炉1は、通常のガラス溶融炉に
使用されるAl23 −ZrO2 −SiO2 系電鋳煉
瓦、ZrO2 系電鋳煉瓦の耐火物2で構築されており、
ガラス原料投入口3と流出口4及びオーバーフロー部5
とを有する。ガラス溶融炉1の炉底には1台のトランス
から12対の電極を配設してある。図1中では、電極対
の各側12本の電極をまとめてそれぞれ電極6として示
してある。電極6に接続されているトランス7の接続導
線8は、アースEから各々の電極6に正電流のみが流れ
るようにした電流整流器9と可変抵抗器10及び可変リ
アクトル11を介してアースEに接続してある。アース
Eの接続先としては、接地母線や建屋のはり、あるいは
溶融炉架台等のアース電位と同一と考えられる場所を自
由に選択できる。
The glass melting furnace 1 is constructed of a refractory 2 of Al 2 O 3 --ZrO 2 --SiO 2 type electroformed brick or ZrO 2 type electroformed brick used in a normal glass melting furnace.
Glass raw material inlet 3, outlet 4 and overflow section 5
Have and. On the bottom of the glass melting furnace 1, 12 pairs of electrodes are arranged from one transformer. In FIG. 1, twelve electrodes on each side of the electrode pair are collectively shown as electrodes 6. The connecting conductor 8 of the transformer 7 connected to the electrode 6 is connected to the earth E via the current rectifier 9 and the variable resistor 10 and the variable reactor 11 in which only a positive current flows from the earth E to each electrode 6. I am doing it. As a connection destination of the earth E, a place which is considered to be the same as the earth potential such as a ground bus bar, a building beam, or a melting furnace base can be freely selected.

【0011】かかるガラス溶融炉1において、As2
3 を重量換算で約1.3%含有するガラス原料12を原
料投入口3から投入し、電極6による通電と、ガス加熱
の併用により約1500℃で溶融した。通常、As2
3 は電極により容易に還元されて金属Asとなり、さら
に金属Asは昇華し易く泡を発生させるため、電極6で
発生した泡が溶融ガラスG中に滞在し、この泡が流出口
4を通ってガラス溶融炉1から取り出されて成型される
ガラス製品に混入するため重大なガラス欠陥の原因とな
る。
In such a glass melting furnace 1, As 2 O
A glass raw material 12 containing about 1.3% by weight of 3 was charged from the raw material charging port 3 and melted at about 1500 ° C. by the combination of energization by the electrode 6 and gas heating. Usually As 2 O
The metal 3 is easily reduced by the electrode to form metal As, and the metal As easily sublimes to generate bubbles. Therefore, the bubbles generated at the electrode 6 stay in the molten glass G, and the bubbles pass through the outlet 4. Since it mixes with the glass product taken out from the glass melting furnace 1 and molded, it causes a serious glass defect.

【0012】本実施例において、溶融に際しては、電極
6間に60Hz交流を、電極6表面の電流密度が0.2
〜1.0A/cm2 の範囲で印加した。電極6対間に交
流が印加されると、各々の電極6は正極になる場合と負
極になる場合とを交互に繰り返す。この時、電極6の表
面には電流整流器9により正電流が負電流よりも多く供
給される。電極6が正極になっている場合、大部分の正
電流は電極6の表面から溶融ガラスGを通り他方の電極
6に直接流れ、一部の正電流が溶融ガラスGから耐火物
2を通ってアースEへ漏れ、電流整流器9を通って他方
の電極6に接続されたトランス7へ流れる。また、電極
6が負極になっている場合には、負電流は電極6の表面
から溶融ガラスGを通り、他方の電極6に直接流れるの
みで、耐火物2を通ってアースEを経由して他方の電極
6のトランス7へは流れない。アースEから電極6へ
は、可変抵抗器10及び可変リアクトル11により、3
0〜80mAの正電流を流すようにした。溶融ガラスG
は、流出口4を通った後ガラス溶融炉1から取り出さ
れ、ガラス製品に成型される。また、溶融ガラスGの表
面層はスカム等が浮遊して汚れているので、オーバーフ
ロー部5からガラス溶融炉1外へ排出される。斯様にし
て、ガラス原料12の溶融を連続して行ったところ、流
出口4から製品として取り出したガラス中には、ガラス
欠陥となる泡は全く含まれていなかった。
In this embodiment, when melting, 60 Hz alternating current was applied between the electrodes 6, and the current density on the surface of the electrodes 6 was 0.2.
The voltage was applied in the range of ˜1.0 A / cm 2 . When an alternating current is applied between the pair of electrodes 6, each electrode 6 alternately turns into a positive electrode and a negative electrode. At this time, more positive current than negative current is supplied to the surface of the electrode 6 by the current rectifier 9. When the electrode 6 is a positive electrode, most of the positive current flows from the surface of the electrode 6 through the molten glass G and directly to the other electrode 6, and some positive current flows from the molten glass G through the refractory 2. It leaks to the earth E and flows through the current rectifier 9 to the transformer 7 connected to the other electrode 6. When the electrode 6 is a negative electrode, the negative current only flows from the surface of the electrode 6 through the molten glass G and directly to the other electrode 6, and passes through the refractory 2 and the earth E. The other electrode 6 does not flow to the transformer 7. 3 from the earth E to the electrode 6 by the variable resistor 10 and the variable reactor 11.
A positive current of 0 to 80 mA was applied. Molten glass G
After passing through the outlet 4, the glass is taken out of the glass melting furnace 1 and molded into a glass product. Further, since the surface layer of the molten glass G is soiled by scum and the like, it is discharged from the overflow section 5 to the outside of the glass melting furnace 1. In this way, when the glass raw material 12 was continuously melted, the glass taken out from the outlet 4 as a product did not contain bubbles that would cause glass defects.

【0013】これに対して、電流整流器を接続しない従
来型のガラス溶融炉において、同種のガラスを同じ条件
で溶融したところ、流出口から取り出したガラス中に
は、電極でAs23 が還元されることに起因する泡が
多く含まれていた。このことは、本実施例における本発
明のガラス溶融炉1においては、電極6の表面で+電荷
の作用によって金属イオンの還元析出が防止されたこと
を示すものである。また、電流整流器を接続しない従来
型のガラス溶融炉においては、流出口の電位は−120
mVであったが、電流整流器を接続した後は最大で+3
30mVとなった。これは、電流整流器を接続しない場
合には電極より−電荷が供給されており、電流整流器を
接続した後は、逆転して電極より+電荷が供給されてい
ることを示しており、本実施例のガラス溶融炉1におい
て、電極6の表面で+電荷の作用が実現されていたこと
を示すものである。
On the other hand, when the same type of glass was melted under the same conditions in a conventional glass melting furnace without a current rectifier, As 2 O 3 was reduced at the electrode in the glass taken out from the outlet. It contained a lot of bubbles due to being processed. This indicates that in the glass melting furnace 1 of the present invention in this example, the reduction and precipitation of metal ions was prevented on the surface of the electrode 6 by the action of + charge. In a conventional glass melting furnace without a current rectifier, the outlet potential is -120.
It was mV, but +3 at maximum after connecting the current rectifier
It became 30 mV. This indicates that −charge is supplied from the electrode when the current rectifier is not connected, and reversely supplied after the current rectifier is connected and + charge is supplied from the electrode. It shows that the action of + charge was realized on the surface of the electrode 6 in the glass melting furnace 1.

【0014】尚、上記実施例においては、アースから電
極に正電流のみが流れる場合を例にとって説明したが、
マイナスイオンの酸化が問題になるガラスの場合にはア
ースから電極に負電流が流れるように電流整流器を介し
て接続すればよく、この場合には、上記実施例とは正負
が逆になるだけで同様の作用となり、電極の表面に負電
流が正電流よりも多く供給されることとなり、−電荷の
作用により、O2-等のマイナスイオンが酸化されずに発
泡を防ぐことができる。
In the above embodiment, the case where only a positive current flows from the ground to the electrode has been described as an example.
In the case of glass where the oxidation of negative ions is a problem, it suffices to connect it via a current rectifier so that a negative current flows from the ground to the electrode. As a result, the negative current is supplied to the surface of the electrode in a larger amount than the positive current, and the negative charges such as O 2− are prevented from being oxidized by the action of the −charge so that the foaming can be prevented.

【0015】[0015]

【発明の効果】以上説明したように、本発明のガラス溶
融炉によれば、電極対の各々とアースの間に、アースか
ら電極に一定方向の電流のみが流れるように電流整流器
を介していることにより、ガラス中の金属酸化物の還元
析出を防止でき、またマイナスイオンの酸化防止ができ
るので、従来に比べて電極の寿命を延ばすことができ、
しかも高品位のガラスを得ることができる。従って、安
価で効率の良い直接通電加熱ができるという優れた効果
を奏する。
As described above, according to the glass melting furnace of the present invention, a current rectifier is provided between each pair of electrodes and the ground so that only a current in a fixed direction flows from the ground to the electrodes. By doing so, it is possible to prevent the reduction and precipitation of the metal oxide in the glass, and also to prevent the oxidation of negative ions, it is possible to extend the life of the electrode compared to the conventional,
Moreover, high-quality glass can be obtained. Therefore, there is an excellent effect that direct current heating can be performed inexpensively and efficiently.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明にかかるガラス溶融炉の説明図である。FIG. 1 is an explanatory view of a glass melting furnace according to the present invention.

【符号の説明】[Explanation of symbols]

1 ガラス溶融炉 2 耐火物 3 原料投入口 4 流出口 5 オーバーフロー部 6 電極 7 トランス 8 接続導線 9 電流整流器 10 可変抵抗器 11 可変リアクトル 12 ガラス原料 G 溶融ガラス E アース 1 Glass Melting Furnace 2 Refractory 3 Raw Material Inlet 4 Outlet 5 Overflow Part 6 Electrode 7 Transformer 8 Connection Lead Wire 9 Current Rectifier 10 Variable Resistor 11 Variable Reactor 12 Glass Raw Material G Molten Glass E Earth

───────────────────────────────────────────────────── フロントページの続き (72)発明者 竹内 宏和 滋賀県大津市晴嵐2丁目7番1号 日本電 気硝子株式会社内 (72)発明者 野口 和也 滋賀県大津市晴嵐2丁目7番1号 日本電 気硝子株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hirokazu Takeuchi, 2-7-1, Harashira, Otsu-shi, Shiga Nihon Denki Glass Co., Ltd. (72) Inventor, Kazuya Noguchi 2-7-1, Hararashi, Otsu, Shiga No. within Nippon Electric Glass Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 溶融炉内に配設された電極対の各々とそ
れに接続されたアースとが、アースから電極に流れる電
流の方向を一定とするように電流整流器を介して接続さ
れてなることを特徴とするガラス溶融炉。
1. A pair of electrodes arranged in the melting furnace and a ground connected thereto are connected via a current rectifier so that the direction of current flowing from the ground to the electrodes is constant. Glass melting furnace characterized by.
JP11596694A 1994-05-02 1994-05-02 Glass melting furnace Pending JPH07300318A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11596694A JPH07300318A (en) 1994-05-02 1994-05-02 Glass melting furnace

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11596694A JPH07300318A (en) 1994-05-02 1994-05-02 Glass melting furnace

Publications (1)

Publication Number Publication Date
JPH07300318A true JPH07300318A (en) 1995-11-14

Family

ID=14675551

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11596694A Pending JPH07300318A (en) 1994-05-02 1994-05-02 Glass melting furnace

Country Status (1)

Country Link
JP (1) JPH07300318A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19802071A1 (en) * 1998-01-21 1999-04-01 Schott Glas Direct electrical heating of a glass melting unit
JP2006028014A (en) * 2004-07-13 2006-02-02 Schott Ag Electric earthing device of float glass manufacturing apparatus
JP2015110518A (en) * 2007-08-08 2015-06-18 コーニング インコーポレイテッド Molten glass delivery apparatus for optical quality glass
KR20210027126A (en) 2019-08-28 2021-03-10 에이지씨 가부시키가이샤 Glass melting furnace and method for producing glass

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19802071A1 (en) * 1998-01-21 1999-04-01 Schott Glas Direct electrical heating of a glass melting unit
JP2006028014A (en) * 2004-07-13 2006-02-02 Schott Ag Electric earthing device of float glass manufacturing apparatus
KR101226033B1 (en) * 2004-07-13 2013-01-24 쇼오트 아게 Device for electrically grounding a float glass production apparatus
JP2015110518A (en) * 2007-08-08 2015-06-18 コーニング インコーポレイテッド Molten glass delivery apparatus for optical quality glass
KR20210027126A (en) 2019-08-28 2021-03-10 에이지씨 가부시키가이샤 Glass melting furnace and method for producing glass

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