【China Aluminum Network】 Refractory materials are the main materials for aluminum melting at high temperature. The aluminum furnaces mainly include reverberatory furnaces, rotary drum furnaces and induction furnaces. The operating temperature is generally 700-1000°C. The damage of such furnace linings is mainly caused by the penetration and scouring of aluminum liquids. The linings are generally constructed of clay bricks, high-alumina fire bricks, and corundum mullite bricks. High-aluminum refractory castables and refractory can also be used. Plastic production, due to the use of good conditions, the furnace life is longer.
1Refractory material for reverberatory furnace
The furnace is divided into two kinds of fixed and tilting, generally using gas or heavy oil as fuel. Aluminium smelting is usually carried out using non-working refractory refractory mats and clay refractory fire-retardant bricks in fixed reverberatory furnaces. The working layer above the molten pool is usually constructed of clay bricks, and high-alumina refractory castables can also be used as prefabricated blocks. Lifting or irrigating on the site or using high aluminum fire-resistant plastics, the molten bath working layer is different according to the use of different materials, and its material is also different. Under normal circumstances, the use of high alumina refractory bricks with Al2O3 content of more than 75% ,Al2O3 content of 80% can also be used outside the high-alumina refractory castable watered into the overall working layer, when smelting high-purity aluminum, the working layer of the bath should use high purity mullite brick, zircon brick or corundum Brick masonry can also be combined with Zhisheng 233 high-temperature heat reflective coating as a thermal energy layer to effectively protect the refractories and reduce heat radiation. Put aluminum, flow aluminum tank and its lining body, in order to resist the penetration and erosion of aluminum liquid, generally use large-scale silicon carbide brick masonry.
The refractories used in the moisturizing furnace and its flux and alloy material processing chambers are basically the same as those of the reverberatory furnace. When aluminum ingot or scrap aluminum is used as raw material, it can be directly loaded into the furnace from the charging port for smelting. When using electrolytic aluminum as raw material. First, the aluminum liquid is sucked out of the bottom of the aluminum electrolytic cell by a siphon tube or a vacuum bag, and is then transported to the reverberatory furnace. After pouring from the charging port, after loading, chlorine gas is blown into the molten pool while being heated for dehydrogenation. The siphon lining is generally made of fire-resisting fiber reinforced lightweight fire-resistant castable for thermal insulation layer, and clay insulation can also be used. Refractory brick masonry, the working layer commonly used dense clay brick or corundum brick masonry. The vacuum insulation package inside the village is the same as the siphon. Its working layer is constructed with high-quality clay bricks or high-alumina refractory bricks. Under normal operating conditions, the service life of the reverberatory furnace and holding furnace is generally 2-5a.
2 Rotary furnace refractory
The non-working layer of the furnace is made of clay insulation firebrick or floating bead brick. It can also be used for watering or prefabricated blocks made of light weight refractory castables with a bulk density of 1.0g/cm3. For aluminum refractory bricks with aluminum content greater than 55%, the drum furnace life is generally 300-500 times. When adding salt flux smelting aluminum blocks. Due to the increased chemical erosion, the furnace life is reduced. In this case, the ZS-1021 high-temperature sealing coating can be applied as a protective layer, and the anti-corrosion and anti-oxidation effects are obvious.
3 Refractory materials for induction furnaces
The furnace lining is generally masonry with clay bricks or three-level high-alumina refractory bricks. The bottom of the furnace is sometimes flooded with a high-alumina refractory castable and then high alumina refractory bricks. When the capacity of the induction furnace is less than 10t, the lining body can be made of a high-alumina refractory castable having a content of Al2O3 of about 75% or a refractory ramming mix, and a corundum refractory castable or a dry vibrating material can also be used. The lining around the inductor coil of the furnace generally uses the corundum refractory castable as a whole or vibrates with a dry vibrating material. Due to the different types of raw materials and exploration conditions, the service life of the furnace is also different, and the general furnace is 0.5-4.0a. During use, vulnerable areas such as the lining around the coil should be repaired 1-5 times.
4 refractory materials for holding furnace
Aluminum holding furnaces are divided into slot-shaped induction furnaces, resistance-heating pool furnaces and gas-fired furnaces. Due to the lower working temperature, such equipment generally uses clay bricks and other materials as the lining body, and also obtains a high service life.
5 Refractory material for slot induction furnace
The lining structure of the furnace is to lay a 10mm asbestos plate or refractory fiber mat on the furnace shell first, and then build a clay thermal insulation refractory brick or a floating bead brick as a thermal insulation layer; the working layer of the furnace and the coil surrounding lining body generally use clay Quality refractory ramming material ramming, can also use clay refractory castable on-site watering, the working layer of large trough induction furnace, with Al2O3 content of more than 55% of high alumina refractory brick masonry, zui good use of ZS-1 high temperature Thermal insulation coating combined with high alumina bricks as an increase in insulation layer, refractory effect zui good.
6 Refractory Material for Heated Pool Furnace
The non-working layer of the furnace is made of clay insulation firebrick, floating bead brick or heat insulation board. It is also possible to use the lightweight refractory castable with a bulk density of 0.8g/cm3 as a whole; the working layer of the molten pool is made of high-alumina refractory bricks with an Al2O3 content of approximately 80%, and high-aluminum materials with a bulk density of 2.4g/cm3 can also be used. Fire-resistant fire casting material. The working layer above the molten pool is generally constructed of clay bricks or refractory castable prefabricated blocks, but can also be made of high alumina refractory plastics.
7 Refractory materials for gas-fired furnaces
The furnace consists of a furnace bottom, a furnace wall and a furnace top. Can be used alone, in order to save energy, easy to manage, can also be used in conjunction with aluminum reflector furnace. Its lining material is clay brick and high-alumina fire brick.
8 Refractory materials for aluminum water tanks
Aluminum water tanks are thermal equipment used to hold aluminum fluids, transport, and casting. The non-working layer of the tank wall is constructed of a clay refractory fireproof brick, and can also be watered using a lightweight refractory castable having a bulk density of 1.5 g/cm3. The working layer is made of clay bricks or high-alumina refractory bricks. It can also be cast entirely using alumina hollow ball refractory castables. The bottom of the tank is made of high-alumina refractory bricks, or it is cast entirely of corundum refractory castables. Smear as protective layer. Due to the erosion and erosion of the molten aluminum, the casting nozzle is usually constructed of silicon carbide bricks, corundum bricks or fused silica bricks. China's ordinary stopper device controls the pouring of aluminum liquid in aluminum water tanks.
9 Aluminum Refining Refractory
The thermal equipment used for refining is an electrolytic cell. The wall of the trough is masonry brick, and the rest parts are made of clay brick and high-alumina firebrick. During electrolysis, the trough temperature is generally 720-800° C. The trough liner is used under good conditions and the operating temperature is low, so the service life is longer.
