SU1189818A1 - Method of glass melting and bath glassmaking furnace - Google Patents

Description

The invention relates to the construction materials industry, in particular to the technology and design for melting glass,

The aim of the invention is to increase productivity, reduce fuel consumption and improve the quality of the glass.

The drawing shows a diagram of the glass-cure bathtub, plan.

A glass melting furnace 1 with a duct 2 is equipped with a burner system 3. In the cooking zone of the glass furnace furnace! mounted on the axis of the furnace, the bottom vertical electrode 4 at a distance from the end of the loading wall 5. The ratio of the distance £, to the width of the furnace is 1.2—!, 6. On the side loading wall 5 at the side, walls b of the furnace 1, at least two horizontal electrodes 7, located below the furnace circumference, are mounted,

In the zone of clarification of the furnace! mounted at the vertices of an equilateral triangle directed toward the channel 2, vertical electrodes 8, the minimum distance from the electrode 8 to the channel 2 is equal to the side of the equilateral triangle i and is 0.4-0.6 the width of the furnace.,

The furnace works as follows.

Thoroughly mixed components of the charge together with a battle of glass loaders are placed in the bathroom of a glass-melting furnace 1 on the molten glass mass. δ cooking zone under the action of flame heating with burners 3 and electrodes 4 and 7, located in the glass below the mixture, carry out the heating and melting of the mixture. Electrode 4 creates a thermal barrier in the path of movement of the charge and stabilizes the position of its boundary. Under the action of electrodes 4 and 7, in the cooking zone, a local convective flow of glass mass is created. The second convective glass mass flow is created in the clarification zone due to electric heating of the glass mass using electrodes 8. Due to the fact that electrodes 8 are located at the vertices of an equilateral triangle and are separated from one another at a distance of 0.4-0.6 the width of the furnace, uniform heating of the glass melts is provided , and the velocities of the endpoints of the objective flows at the walls of the furnace 1 and along its axis differ by no more than 20 £. This provides improved furnace performance with high quality glass melt.

Table 1 shows the results of the load distribution over the electrodes at a different distance of the bottom vertical electrode from the end wall of the furnace with a power ratio / Р ^ -1.25 1.75 (in - the width of the furnace

From table 1 it can be seen that the optimal ratio of the distance from the end loading wall to the bottom vertical electrode in the cooking zone to the furnace width is 1.2-1.6 (the deviation from the uniform distribution of the load over the phases does not exceed 1% '.

The choice of the optimal location of the data: vertical electrodes in the zone of clarification of the glass-melting furnace bath is carried out by determining the speeds of convective flows along the axis of the furnace and near its side stack on the physical model.

According to the method of conducting research on a physical model, the stove oven stack first reproduces the thermal stationary mode for the case without electric heating. Then, the required power is introduced into the model using graphite electrodes.

The creation in the clarification zone of a transverse row of two to three electrodes is impractical, since with a small furnace width (2.4 m) and low electrical conductivity of glass mass (1.4 ohm cm at 1400 ° С1 there is a large current density and uneven loading of the phases, which leads to a greater irregularity of the velocities of the convective sources of the glass melt across the width of the furnace in the pre-flow region.

The most appropriate location of the electrodes in the zone of clarification at the vertices of an equilateral triangle, directed in the direction of the duct,

The maximum distance to the duct is determined both by the erosion of the refractory of the flow wall and the need to create an ascending convective flow near the flow wall to prevent the ingress of polluted glass mass to the output.

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Tests have shown that the minimum distance from the duct to the outermost electrode in the clarification zone, determined from the indicated conditions, is 0.4-0.6 of the furnace width.

Normal operation of the furnace occurs when the ratio of the speeds of convective glass mass flows along the axis of the furnace (V?) To the same at the side walls of the furnace and ν ^), equal to 10

V, - ν ₂ = (0.8-1.2) ν ₂ .

Table 2 presents the results of test options with the location of vertical electrodes in the clarification zone at the vertices of an equilateral triangle with sides of 600–1800 mm and the speed of convective glass melt flow.

From table 2 it is seen that the ratio of 20 speeds of convective glass mass flows, equal to V- = (0.8-1.2) ν ₂ ,,

Experiments 2–4 correspond to the location of the electrodes in the clarification zone at the vertices of an equilateral 25th triangle with a side equal to 0.40.6 kiln widths.

Experiments were carried out on the physical model to vary the ratio of the additional electric power input in the cooking zone P ,, and the clarification zone P ₂ , with Ρ ^ / Ρχ changing from 0.5 to 3.

Table 3 shows the results of the tests carried out, and in

As a base characteristic, the time T was chosen, expressed as a dimensionless quantity, defined as the ratio of the residence time of the glass melt in the electric heating furnace to the residence time of the glass melting in the furnace without electric heating.

From the table. 3 it can be seen that with the power ratio of the additional electric heating in the cooking zone and the clarification zone 0.5-1 (experiments 1-3) and 2-3 (experiments 7-11), the dimensionless residence time of the glass melt in the furnace is 1, 06-1.25, i.e. the absolute residence time of the glass melt in the furnace with additional electric heating increases compared with the absolute residence time of the glass mass in the furnace without additional electric heating by only 5.5-20%, while in the optimal variant (tests 4-6) with respect to the additional power electric heating in the cooking and clarification zone 1.25-1.75 absolute time of glass mass in the furnace increases by 28–33%.

Tests of the method of melting glass and furnaces have shown that the productivity of chechea is increased by 22% compared with the base case with a similar increase in the coefficient of glass melt utilization and a decrease in fuel consumption by 12%.

Table 1

Experience The distance of the bottom vertical electrode from the end loading wall ({.,) mm Ratio ^ / B The load distribution over the electrodes,%. , · I II III one 960 0.4 38 31 31 2 1920 0.8 36 32 32 3 2400 one 35.4 32.2 32 (famous) four 2880 1.2 34 33 33 five 3360 1.4 33.3 33.3 33.3 6 3840 1.6 32 34 34 7 4320 1.8 thirty 35 35

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table 2

Experience

The distance between the electrodes, i,

mm

Convective flow rate, m / h

ι / 3

one 600 0.6 0.1 0.6 6.0 0.25 2 960 0.36 0.3 0.36 1.2 0.4 3 1,200 0.35 0.35 0.35 1.0 0.5 four 5,440> 0.32 0.40 0.32 0.8 ‘ 0.6 five ‘1800 0.15 0.55 0.15 0.275 0.75 G a blitz 3

Experience ^P 1 / ^r g L ί V but 0.50 1.06 2 0, 75 1.10 3 ! , 0 1, 20 four 1.25 1, 40 five I ₂ 50 ! 45 6 1.75 1.50 7 2, 00 1, 25 eight 2.25 1, 20 9 2.50 1.15 ten 2.75 1.12 eleven 3.0 1.10

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Claims (2)

I. Method of melting glass by supplying the charge to the furnace, heating it with gas-electric, homogenizing and clarifying the melt obtained, characterized in that, in order to increase productivity, reduce fuel consumption and improve the quality of the glass melt, the ratio of elec- tric; tric power in the zones of boiling and clarification is set equal to 1.25-1.75. 2. Bathroom glass furnace containing duct-connected production and cooking pools, the latter of which is made with cooking, homogenization and clarification zones, with burners, horizontal electrodes installed in the end wall of the loading wall, and vertical electrodes located along the axis in the cooking zone and symmetrically axes in the clarification zone, characterized in that, in order to improve the performance of the furnace, reduce fuel consumption and improve the quality of glass, the vertical electrode in the cooking zone is mounted at a distance from the front loading wall equal to 1.2–1.6 of the furnace width, and in the lightening zone vertical electrodes are installed at the corners of an equilateral triangle, directed apex towards the duct, with a distance to the latter equal to the side of an equilateral triangle and 0.4 0.6 oven width. 1189818 1 11