Electrodes glass melting

Chlorination in shaft electric furnaces. A shaft furnace is a steel apparatus lined on the inside with a layer of diabase on liquid glass and a layer of special low porosity chamotte brick. The lower part of the furnace has two rows of coal electrodes (three in each row). The lower part of the furnace is filled with coal packing to 400-700 mm above the top electrodes. The melted metal chlorides flow down the heated packing. They are collected in the lower zone of the furnace and periodically unloaded. 

Fig. 4.4 Heating a glass melt the power (I2R) is introduced directly into the melt via tin oxide electrodes.

Refs. [i] Baucke FGK (2000) Electrochemistry cf solid glasses. In Bach H, Baucke FGK, Krause D (eds) Electrochemistry cf glasses and glass melts, including glass electrodes. Springer, Berlin, pp 35-268 [ii] Baucke FGK (1998) / Phys Chem B 102 4835... 

Electric melting furnaces with molybdenum electrodes are unsuitable wherever glass melt interacts with molybdenum electrodes bringing about contamination of... 

A suitable method for measuring the conductivity of glass melts up to 1450 °C has been described by Stanck et al. (1965). An AC source of 800 Hz frequency was used in order to eliminate polarization, and platinum electrodes were employed. The results obtained with several types of industrial glasses are shown in Fig. 58. Their compositions are listed in Table IJ. 

Use of molybdenum electrodes for melting lead glasses may be considered in combination with anodic protection (passivation) which prevents separation of lead at the electrodes and suppresses corrosion (Susser et al., 1977). 

Experimental arrangement for measuring thermoelectric emfs of glass-forming melts by means of zirconia microelectrodes. (1) Zirconia electrodes (2) melt (3) temperature gradient furnace (4) leads from PtiOj reference electrodes (5) leads from thermocouples (6) reference gas inlet (7) outlet. 

The final example is concerned with standard Seebeck coefficients of glass melts, which were accessible after zirconia electrodes had been developed [12]. Continuously working glass melting units are characterized by nonisothermal operation, and metals, eg, platinum-type metals, contacting the melt and often short-circuited are subject to electrode reactions, eg, generation and consumption of oxygen, which can indirectly impair the production of the melters. Thermoelectric emfs of such nonisothermal cells. 

Sn02 Electrodes for electric glass melting furnaces... 

Sn02 is frequently used as electrodes in glass melting furnaces, particularly those used for making glasses for optical components and lead crystal tableware. The requirements for the electrode material are very specific ... 

Reduction of temperatures of glass melting and pouring on the account of boron additives specially included into an initial solution. This will allow a decrease in the melting temperature up to 850°C and thereby lessen corrosion of refractory, electrodes, water-cooled elements, and sensors of control and measuring instruments. 

Bach H, Baucke FGK, Krause D (2001) Electrochemistry of glasses and glass melts, including glass electrodes. Springer, Berlin Heidelberg New York... 

Tin oxide electrodes have been used to melt glass for more than 50 years. In October 1965, Plumat et al. (Plumat, Jaupain, Toussaint, 1965) presented a paper on the use of tin oxide bricks as glass melting electrodes at a glass conference. 

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