ISSN 0862-5468 (Print), ISSN 1804-5847 (online) 

Ceramics-Silikáty 35, (3) 211 - 223 (1991)


THE CHEMICAL, PHASE AND ENTHALPY BALANCE OF CHANGES IN THE PRE-HEATED BATCH FOR THE EUTAL GLASS

PART I. DETERMINATION OF THE MASS BALANCE OF THE ESCAPE OF GAS REACTION PRODUCTS


 
Eliášová Mária 1, Košecký Milan 2, Rekeňová Mária 1, Proks Ivo 1, Pechová Eva 1
 
1 Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská 5, 842 36 Bratislava, Czechoslovakia
2 Institute of Glass Research and Development, SNP street 20, 912 50 Trenčín, Czechoslovakia

The mass balance of gaseous reaction products (CO₂, H₂O and gaseous forms of boric acid) escaped during the process of heating of the pressed Eutal glass batch in the range of 25 - 800 °C a) in the stream of N₂ and b) in the stream of natural gas combustion products of the approximate composition as 70 vol. % N₂, 20 vol. % H₂O, 10 vol. % CO₂ was determined. The termogravimetry, atomic emission spectrometry, DTA and X-ray diffraction techniques were used in this investigation. This paper is focused on determination of the boric oxide mass decrease in the pre-heated batch as a temperature function that is due to reactive vaporization in the presence of water vapour. The total relative loss of boric oxide from the pressed batch with an initial content of B₂O₃ equal to 6.8 % is about 14.5 % when the batch is pre-heated in the stream of combustion products whereas reheating the batch in the nitrogen stream results in a loss of 6.8 % . The value of the B2O3 loss depends consequently upon the content of structural water in the batch components, as well as upon the water in the natural gas.


PDF (1.1 MB)
 
Licence Creative Commons © 2015 - 2022
Institute of Rock Structure and Mechanics of the CAS & University of Chemistry and Technology, Prague
Webmaster | Journal Contact