SU1025670A1 - Method for melting glass - Google Patents

Description

The invention relates to the building materials industry and can be used for cooking varieties, packaging and technical glassware. The glass melting process includes four main stages: silicate crazing, glass formation, clarification and homogenization (averaging) of glass melt. In traditional glass melting furnaces, both regenerative and direct heating furnaces, all stages take place in the same chamber (basin) and, therefore, are combined to one degree or another. The specificity of the progress of these stages of glass melting requires different thermal conditions in the furnace zones and constructive implementation. For this purpose, glass melting is carried out in separate chambers, in common with channels, each of which organizes an optimal autonomous thermal and hydrodynamic regime, which significantly increases the efficiency of the process compared to with the traditional cooking method in a single-chamber bath. Even more effective is the melting of glass using electricity. However, the efficiency of the known systems of electric heating of the glass mass does not exceed 60-70, since reverse flow of glass mass usually takes place in the furnace bath. In addition, the known electric heating systems provide a current density in the glass mass of 0.06 A / m, which does not allow the glass to be cooked with high efficiency. There is a known method of glass melting, which includes the process of silicate formation, the glass image of the erosion, clarification, and homogenization. The clarification of glass melts in a thin film flowing down a special rotating rod from the silicate-glass formation zone to the production pool. At the same time, a sufficiently high rate of clarification of the glass mass is ensured. The disadvantage of this method is the limited possibilities for intensifying the glass formation process, since the heat exchange in the cooking zone is organized in the traditional way. The glass melting process is known, which includes the process of silicate formation, glass formation, homogenization and clarification in two baths arranged one under the other and connected by a vertical channel. Glass mass fine. the film flows along the walls of the channel from the zone of silicate and glass formation to the zone of clarification, mixing and partially lightening 2j. The disadvantage of this method of glass melting is the low intensity of the glass formation process. The closest to the proposed technical essence and the achieved result is the method of glass melting, which includes supplying the charge, melting and dropping the glass in the jet from one basin of the furnace to another when heating the jet f3. However, when using a flame directed to a perpendicular to the falling glass mass, it is almost impossible to heat the glass mass to a temperature above 1650-1700 0 due to the low effective temperature of the torch (1700-1750 C under normal conditions and 1850-1900 C using oxygen ); low heat transfer coefficient from the torch to the glass melt and a small area of contact between the products of combustion of fuel and glass mass; low thermal conductivity of glass mass. The purpose of the invention is to reduce specific fuel consumption and increase the specific consumption of glass melt. This goal is achieved by the fact that in the method of glass melting, which includes supplying the charge, melting and dropping the glass mass in the jet from one basin to another when the jet is heated, the jet is heated by passing an electric current of 0-YO A / cm through it, and the fall time jets 1-lfc. Example. and) ichthi served in the upper bath of the furnace through the boot pocket. At a temperature of 1200-100 ° C, which is ensured due to the burning of the fuel, their charge forms the primary glass mass: from silicates and undissolved grains of dioxide or silica. Through a special tray of glass melt it falls into the lower chamber of the furnace. Through a stream of glass melt current is passed. Since the jet cross section at an average height does not exceed 3-6 cm /, the current density can reach values of up to 150 A / cm, which is 2500 times greater than in furnaces with known methods of electric heating of glass melt. The high current density in the jet of glass melts provides its heating to high temperatures (1600-2100 С),

which greatly intensifies the glass formation processes.

The processes of clarification and homogenization of glass melt proceed in the basin of the lower chamber of the furnace. Next, the glass melt through the duct enters the production.

The residence time of the primary molten glass melt and current density are determined by the composition of the glass and the productivity of the furnace. When cooking refractory glasses, the current density and residence time in the jet must be, respectively, A / cm and 3 s, the discolored glass 50100 A / cm and 2-3 s, dark green glass - kO-60 A / cm and 1.5 -2.5 s.

The lower limit of the indicated parameters: the current density of 40 times 1 s is determined by the fact that with smaller values of these parameters the proposed method of glass melting has special advantages as compared with the known ones. When the density of tokb is more BUT A / cm, intensive foaming of the glass mass is possible, which ultimately significantly reduces the efficiency of the prog. glass cooking process in general. With an increase in the residence time of the glass melt in the jet more than C, the dimensions of the furnace do not rationally increase.

Depending on the performance of the furnace and its design features, the stream of glass melt in the cross section can be round or rectangular. The latter is achieved if the tape is drained from the tray.

The advantage of the proposed glass melting method is that more electric power is used, and the capacity of the furnace is increased by a factor of 1.53.

Claims (1)

METHOD OF GLASS BREWING, including feeding the mixture, melting and dropping the molten glass in the stream from one furnace basin to another when the stream is heated, characterized in that, in order to reduce specific fuel consumption and increase specific glass mass removal, the stream is heated by passing an electric current of density through it 40-. 140 A / cm ⁴ , with a jet fall time of 1-4 s.