The Effect of Fuel Oil on the Aggregation of Glass Batch
Abstract Generated abstract
This study examines the role of fuel oil, used as a reducing agent in sheet glass production, as a binder affecting aggregation of glass batch materials. The authors measured wetting contact angles for quartz, soda sulfate briquettes, and dry and moist batch briquettes, determined fuel oil surface tension by the ring detachment method, and calculated work of adhesion over 24 to 70°C. The results indicate that wetting changes most strongly between 24 and 50°C, moist batch is wetted better than air dry batch, and adhesion is higher at lower temperatures. From the standpoint of fuel oil binding action, the study suggests that more favorable aggregation of the batch occurs at about 24 to 30°C.
Full Text
PROCEEDINGS
of the Tomsk Polytechnic Institute
of the Order of the October Revolution and the Order of the Red Banner of Labor named after S. M. Kirov
Volume 257 1973
THE EFFECT OF FUEL OIL ON THE AGGREGATION OF GLASS BATCH
V. M. Vityugin, L. G. Logova
(Presented by the scientific seminar of the Department of General Chemical Technology, CTF)
In the production of sheet glass at the Anzhero-Sudzhensk Glass Plant, fuel oil is used as a reducing agent instead of coal dust (a mixture of fuel oil grades “40” and “100” is used).
In addition to its reducing properties, fuel oil possesses certain binding properties which, during aggregation of the batch, may play a significant role. The main factors affecting the process of binding batch materials are:
a) the magnitude of the contact angles of wetting \((\theta)\) of the batch components by the binder;
b) the magnitude of the surface tension \((\sigma)\) of the binder;
c) the magnitude of the work of adhesion \((A_{ag})\) between the batch components and the binder;
d) temperature.
The magnitude of the contact angle of wetting was determined by the method described in the work of A. I. Belyaev and E. A. Zhemchuzhina [1].
Taking into account that glass batch consists approximately of 70% silicon dioxide and 21% soda and sulfate, the contact angles of wetting were determined for a quartz plate, soda–sulfate briquettes, and batch briquettes. Briquettes 15 mm in diameter made from a soda–sulfate mixture and from batch materials (air-dry and moist) were prepared under a pressure of 1500 kg/cm². The moisture content of the finished batch tablets was 3.8–4%. The temperature was varied from 24 to 70°, and the change in the moisture content of the briquettes was neglected.
From the results of the experiment (Figs. I, 2) it is evident that the principal change in the magnitude of the contact angle of wetting of the components and of the batch occurs in the temperature interval from 24 to 50°C. With a further increase in temperature to 70°C, the value of $\theta$ changes only slightly. The difference in the wetting of quartz and the soda–sulfate mixture disappears at a temperature of 60°C. It was found that the contact angles of wetting for quartz decrease with time; the drop spreads. When determining the contact angles of wetting of soda–sulfate briquettes, the drop did not spread, but the angles decreased because of absorption of the fuel oil by particles of soda and sulfate.
Fig. I
Change in the magnitude of the contact angle of wetting ($\theta$) of a quartz plate by fuel oil as a function of spreading time at temperatures: 1—24°C, 2—30°C, 3—40°C, 4—50°C, 5—60°C, 6—70°C.
Wet batch is wetted by fuel oil better than dry batch, especially at temperatures above 50°C. The nature of the change in the value of $\theta$ for wet materials is the same as for air-dry materials.
The surface tension of the fuel oil was determined by the ring detachment method. It was established that the value of $G$ decreases, especially markedly in the temperature interval 24–40° (Table I).
Table I
Surface tension of the fuel oil studied at various temperatures
| $t$, °C | 24 | 30 | 40 | 50 | 60 | 70 |
|---|---|---|---|---|---|---|
| $G$, dyn/cm | 82.5 | 65.5 | 55.3 | 53.3 | 51.8 | 50.4 |
Fig. 2. Change in the work of adhesion between fuel oil and materials as a function of temperature:
1 — work of adhesion between fuel oil and a quartz plate;
2–3 — work of adhesion between fuel oil and an air-dry batch; between fuel oil and a soda–sulfate mixture;
4 — work of adhesion between fuel oil and a wet batch.
From the value of the surface tension of fuel oil \(C\) and the contact angle of wetting \(\theta\) between fuel oil and the batch components, the work of adhesion \((A_{ad})\) was determined [2]. The work of adhesion decreases with increasing temperature; at temperatures above \(40^\circ\mathrm{C}\), the work of adhesion changes only slightly. The smaller value of the contact angle of wetting for the wet batch results in the adhesion of fuel oil to the wet batch being higher than to the batch in the air-dry state.
The investigations carried out showed that the components and the batch as a whole are wetted by fuel oil approximately equally. Moistening of the batch promotes better wetting by fuel oil, especially at elevated temperatures. The work of adhesion between fuel oil and the batch increases as the temperature decreases. Consequently, from the standpoint of the effect of fuel oil, better aggregation will correspond to a temperature of...
interval of 24–30°C.
References
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A. I. Belyaev, E. A. Zhemchuzhina. Surface Phenomena in Metallurgical Processes. Metallurgizdat, Moscow, 1952, pp. 9–18.
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O. N. Grigorov, I. F. Karpova, et al. Manual for Practical Work in Colloid Chemistry. Khimiya Publishing House, Moscow–Leningrad, 1964, p. 136.