SU1198027A1 - Method of fusible lead glass melting and electric glass-making furnace for effecting same - Google Patents

Abstract

1. A method of boiling low-melting lead glass by feeding the charge, melting it, flowing through the duct, conditioning and making, characterized in that. that, in order to increase the quality of the glass, to save raw materials and prolong the furnace campaign, the maximum heat load is created in the duct zone, while the ratio of temperatures in the melting zone and duct is set to 0.8-0.95. 2. An electric glass melting furnace containing duct-connected cooking and production pools in which electrodes are installed, characterized in that, in order to improve the quality of glass, save raw materials, materials, and extend the kg: the furnace, the electrodes: high (About full walls, moreover, the area of the working surface of the electrode, both (L of the cooking and working pools) is equal to or more than one and a half square of the duct section.

Description

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The invention relates to the industrial construction materials, in particular, to methods for melting glass in baths of electric furnaces of continuous action of the deep type and devices for glass melting.

The purpose of the invention is to improve the quality of glass, saving money. materials and the renewal of the kiln campaign

Fig. 1 shows the proposed electric furnace, total airfield; FIG. 2 shows a stove with two working pools; on fig.Z - the furnace with the arrangement of electrodes lateral in relation to the channel; 4 is a furnace with a T-shaped flow path.} FIG. 3 is a graph of temperature distribution at different parts of the furnace.

The electric furnace furnace contains a cooking pool 1, which is equipped with electrodes 2 and is connected by a duct 3, a heated power supply source 4 to a production pool 5, equipped with electrodes 6 and a fireproof screen 7, heated by heaters 8. Adjacent to the working pool is a feeder 9, under which rolling mills are installed. rolls 10. Electrodes 2 and electrodes 6 can be located differently with respect to the duct (Fig. 3), their number can also be different (Fig. 1-4).

The method is carried out as follows.

Blend 11 is fed to the cooking basin 1, melted, and the melted glass melt is heated to the cooking temperature. The molten glass heated to the cooking temperature is fed to the duct, where the maximum temperature is developed, it is necessary; To finish boiling and brightening the given Compound, glass. The design of the furnace for carrying out the method makes it possible to create a temperature in the duct at 50-80 ° Bbmie temperature in the area of the installation of electrodes 2 and 6 (electrode layer). Since the main processes of cooking and clarification of glass melt occur in this furnace in the volume of the duct, where maximum temperatures develop, its dimensions must be not less than two volumes of the furnace's hourly output, otherwise the glass melt does not have time to clarify and homo8027i

genius, i.e. its quality is deteriorating. Successive charges of the charge ensure the supply of clarified glass mass to the external pool 5, where the glass mass is maintained by heaters 8 installed above screen 7. 3 working pool 5 glass mass is fed through tray 9 to shaft 10 kts 10 of the working device.

The cooking method was tested on low-melting lead-containing glasses with a PbO content of 75 and 85%.

PRI me R 1. In an experimental electric furnace of a deep-melting glass-making furnace, tests were carried out and the method of cooking glass SC-90-1 containing 75% of lead oxide was tested. The furnace is made of electroalloyed corundum refractories and is equipped with electrodes — blocks of conductive ceramics, based on tin dioxide.

Maximum area ratio

25 of the cooking pool electrode (as well as the working one) to the flow area of the channel was 4. By disconnecting part of the electrode blocks, tests were carried out at a ratio of 1: 1.5j 2.0, - 3.0; 4.0: Weight volume flow of 20 kg of glass mass. Tests were conducted on performance from 6 to 12 kg of glass / h, i.e. when the ratio of the volume of the duct to the hourly productivity of the furnace is 3.3, 2, 1.63.

Figure 5 shows the graphs of the temperature distribution in the furnace over the height of the furnace capacity of 6 kg / h of the Q Qal SL-90-1 stack and the ratio of the electrode area to the duct section area equal to 2, where 1 is the temperature distribution curve over the depth in the center of the cooking furnace. swimming pool; P - curve

., the temperature distribution in depth in the center of the working basin; III - temperature distribution curve “10 depth at the entrance to the duct.

As can be seen from the graph, the zone of maximum temperatures is located in the duct, and the temperature difference on the same level in the cooking basin and duct is 100-130 C. The maximum temperature at the entrance to the duct from the cooking basin is 920 ° С, and the temperature in the cooking basin is same level deep

Q

not 790 C, i.e. the ratio of temperatures in the cooking basin and the flow (with a ratio of electrode and duct sizes equal to 2 is equal to 0.86. The test results for the example are given in Tables 1 and 2. Example 2. In an experimental furnace similar to that specified in Example 1, low-melting glass with a lead oxide content of 85%. The weight of the duct is 20 kg of glass mass. Tests were carried out at a capacity of 6 to 12 kg of glass / h, as well as at the ratio of the electrode surface area to the duct section equal to 1.0v 1.5; 2, 0; 3.0 and 4.0, Figure 5 shows the graphs p temperature distribution in the furnace according to height with a capacity of 6 kg / h and the ratio of the electrode area to the flat area (ad duct section equal to 2 puncture lines). Table ZIL shows the results of the test in Example 2. The quality of the glass melt is visible and Table 2 and i, satisfactorily up to a productivity of 10, which is ½ of the weight volume of the duct. At higher performance, the stability of the composition is disturbed, the homogeneity of the glass mass deteriorates. Experiments have shown that in order to achieve the required temperature ratio between the cooking basin and the duct, which ensures the safety of the electrodes, it is necessary that the electrode area of each of the basin (cooking and production) be equal to or more than one and a half of the duct section. In addition, the ratio of thermal loads, equal to 0.8-0.95, is optimal (Table 1 and 3). With a ratio of less than 0.8, due to a decrease in temperature in the cooking basin, i.e. below the charge, the quality of the glass melts due to penetration of incomplete particles at work. When the ratio is less than 0.8, due to the increase in temperature in the duct, the quality of the glass mass deteriorates due to the temperature, the refractory is destroyed, and the glass is clogged with refractory inclusions. At a ratio greater than 0.95, the temperature in the area of the electrodes reached critical values at which Intense wear of the electrodes, and at a temperature ratio close to 1, the experiment was terminated because of the danger of electrodes leaving the device (the temperature in the electrode layer reached 920 C). Table 1

920/920 1.01-2

870/920 0,955-6

790/920 0,868-9

740/920 0,810-11

720/920 0.7811-12

55 65 65 65 60

1.15

1.0

0.95

0.95

0.95

The ratio of the volume of the duct to the hourly productivity of the furnace

3.3 2.0 1.63

Table 2

% yield (according to the spreadability of 24.5-26.5 mm)

65 65 60

Table3

FIG. one / //

FIG. 2 /

Fig.Z // x

FIG L Gludin mm 600 100 80B FIG. 5 PbO75% -RDO- 85% 1000 then

Claims (2)

1. The method of cooking fusible lead glass by feeding the mixture, melting it, flowing through the duct, conditioning and production, characterized in. that, in order to improve the quality of glass, save raw materials and extend the campaign of the furnace, a maximum of thermal loads is created in the duct zone, while the temperature ratio in the melting zone and duct is set equal to 0.8-0.95. 2. Electric melting furnace, comprising a duct connected to the brewing forehearth and pools in which the electrodes, characterized in that, to improve glass quality, cost of raw materials and Cont ² Lenia kgmpanii furnace electrodes are wall-mounted, the working electrode surface area , both the cooking and developmental basins is equal to or more than one and a half area of the cross-section of the duct.