Glass melting furnaces

The actual name dry scrubbing was first publicized by Teller [U.S. Patent no. 3,721,066 (1973)]. He worked both with classical Army-type soda-lime and with his patented water-activated form of the alkaline feldspar nepheline syenite as a flow agent and feedstock sorbent for HF and SO9 in hot, sticky fumes from glass melting furnaces. He claimed capture of more than 99 percent of 180 ppm HF and SO9 for more than 20 hours in a packed bed of 200 X 325 mesh hydrated nephehne syenite at 42,000/hr. 

E. D. Spinosa, P. M. Stephan, and J. R. Schorr, Review of Literature on ControlTechnology which Abates Air Pollution and Conserves Energy in Glass Melting Furnaces, to Coming Incorporated, EPA-600/2-77-005,/2-76-269,/2-76-032b, Battelle, Columbus, Ohio, Nov. 11,1977. 

Glass-melting furnaces are built nf refractory materials of various types, which will withstand the severe conditions to which they are exposed. The lower portion ill the inciter section, liir instance, must be of the highest quality to withstand the corrosive action of the glass as well as the high temperutures used. Some sections may use lower-quality refractories because the temperature or corrosion conditions are not as severe. 

FIG. 27-52 Side-port continuous regenerative glass melting furnace. 

The thermal efficiency of glass melting furnaces is relatively low, in particular that of pot furnaces. Values of 20—35% are reported for tank furnaces with classical heating (see below). Efforts to raise thermal efficiency led to experiments with shaft and rotary furnaces, with fluidized bed melting furnaces, etc. Only electric boosting and all electric glass furnaces have so far found wider practical application. 

Ginzburg D. B., Glass-Melting Furnaces (in Russian), Stroyizdat, Moscow, 1967 (rnH36ypr A- CTCK.70BapeHHfcie ne jM, CTpOHMSflar, Mocxsa 1967). 

A similar effect can be observed in the corrosion of top horizontal surfaces situated over the melt (e.g. in the throats of glass melting furnaces). A bubble of gas adhering to the interface will develop intensive flow in its neighbourhood as a result of a surface tension gradient and will quite rapidly bore a cylindrical hole in the upward direction ( bubble drilling ). Drops of molten metal act similarly but in the opposite direction (e.g. metallic lead at the glass furnace bottom). 

Glass-melting furnaces can be divided into the following four groups... 

The control of glass melting furnaces is based in particular on correct setting and maintenance of the temperature conditions. The temperature maximum usually occurs at one half or two thirds of the melting zone and the melting itself should be completed before this point is reached. Convection can be promoted and stabilized by eletric boosting or bubbling. 

Exposure to Soda Vapor in Glass Melting Furnaces... 

Fellows, W. D., Application of the thermal deNOx process to glass melting furnaces, 1989 Fall International Symposium, American Flame Research Committee, International Flame Research Foundation, 1989. 

Many researchers have used fine wire thermocouples (T/Cs), with and without coatings. Costa et al. [77] used a bare 300 pm diameter wire uncoated Pt/Ptl3%Rh thermocouple to measure gas temperatures inside an industrial glass-melting furnace. Mital et al. [78] used three different diameter (76,125, and 200 pm) fine wire Type R thermocouples to measure the gas temperature inside porous ceramic radiant burners by extrapolating the measurements to zero diameter. 

G. "Combustion Measurements in an Industrial Glass-Melting Furnace." Journal of the Institute of Energy 69, no. 479 (1996) 80-86. 

Cassiano, J., Heitor, M. V., and Silva, T. F. "Combustion Tests on an Industrial Glass-Melting Furnace." Fuel 73, no. 10 (1994) 1638M2. 

Glass melting furnace operated with regenerative combustion. 

Typical end-port-fired regenerative glass melting furnace. (From Eleazer, P. B., and Hoke, B. C., Oxygen-Enhanced Combustion, Boca Raton, FL CRC Press, 1998.)... 

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