2024-02-28 08:42:39
The anti-seepage casting material has the characteristics of low thermal conductivity and strong resistance to penetration, which can prevent the infiltration and erosion of aluminum liquid and liquid, thereby extending the service life of the electrolytic cell. At the same time, the anti-seepage casting material increases its thermal conductivity due to the electrolyte entering the refractory insulation layer, resulting in an increase in the power consumption of the electrolytic cell. Moreover, the construction of anti-seepage materials is fast and convenient, and they can quickly heat up without the need for baking. They are mainly used in electrolytic cells to replace refractory bricks and Al2O3 layers as impermeable layers. They are a commonly used refractory material for aluminum melting furnaces.
According to the design and material selection of the electrolytic cell, the anti-seepage casting material should ensure that the temperature inside the carbon cathode material is greater than 850 ℃ and has good thermal shock resistance. The anti-seepage material should be used as a barrier layer between the carbon brick and the insulation layer to prevent the infiltration of harmful substances.
The selection principle of anti-seepage pouring material is that if m (AL2O3)/m (SiO2) is greater than 0.9, it can inhibit the penetration of Na and NaF. Because the infiltrated Na and NaF can react with AL2O3-SiO2 refractory materials to form nepheline, which blocks the pores and prevents the continued infiltration of Na and NaF.
The anti-seepage casting material is used between the carbon brick on the side wall of the aluminum electrolysis cell and the insulation layer, which can prevent the penetration of substances such as Na and NaF, and also protect the insulation layer. The critical particle size of the anti-seepage casting material is 3mm, and the mass ratio of bone powder is about 6:4. It is directly laid on the insulation layer at the bottom of the groove.
The main performance of anti-seepage castable is to be heated to 950 ℃ in an electric furnace and maintained for 96 hours. The sealed crucible naturally cools down to room temperature with the furnace, takes out the crucible, cuts open the section for observation and analysis, and measures the remaining height H2 of the anti-seepage material after reacting with cryolite. The penetration depth (H1-H2) is calculated, which is essentially the height of the reaction layer, that is, the material's impermeability.
But anti-seepage castables are also useful in the lead or copper smelting industry. The materials used for anti-seepage in different furnaces are also different. However, regardless of the type of furnace used, thermal expansion and contraction, stable volume, and good thermal shock are the key to anti-seepage.
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