Alumina hollow spheres (3/5mm)

Alumina hollow spheres are a new type of high-temperature insulation material. They are made by melting and blowing industrial alumina in an electric furnace, and the crystal form is α-Al2O3 microcrystals. Using alumina hollow spheres as the main body, various specifications of refractory lightweight products can be made. The maximum use temperature is 1800℃, with high mechanical strength, low thermal conductivity, and stable performance under various atmospheres. They are widely used in high-temperature and ultra-high-temperature kilns such as gasification furnaces in the petrochemical industry, reaction furnaces in the carbon black industry, and induction furnaces in the metallurgical industry, achieving very satisfactory energy-saving effects.

Alumina hollow spheres and their products are a kind of lightweight refractory material with excellent high-temperature resistance and energy saving. Alumina hollow spheres can be used as high-temperature and ultra-high-temperature insulation fillers, lightweight aggregates for high-temperature refractory concrete, and high-temperature castables. Alumina hollow sphere bricks can be used in high-temperature energy-saving (>30%) inverted flame kilns, shuttle kilns, molybdenum wire furnaces, tungsten rod furnaces, induction furnaces, nitriding furnaces, etc. They can significantly reduce kiln weight, improve structure, save materials, and conserve energy.

I. The role of alumina hollow ball in alumina brick is mainly reflected in the following aspects:

1, Enhance the thermal insulation performance

Alumina hollow ball has a low density, high porosity characteristics, its internal hollow structure can effectively reduce the thermal conductivity, significantly enhance the thermal insulation effect of alumina brick. In a high temperature environment, this structure can reduce heat transfer and improve thermal insulation performance, suitable for industrial kiln linings that require thermal insulation.

2, Reduce the weight of the brick body

Through the introduction of alumina hollow balls, the bulk density of alumina bricks can be reduced from 2.6-3.0g/cm³ of traditional heavy bricks to 1.1-1.5g/cm³. Each cubic meter used can reduce the weight of 1.1-1.9 tons, while maintaining the mechanical strength, to achieve structural lightweight.

3, Reduce material consumption and cost

Brick body prepared with alumina hollow ball can save 1.1-1.9 tons of heavy bricks per cubic meter, and reduce 80% of refractory heat preservation material demand. Its energy-saving effect of more than 30%, significantly reducing production costs and energy consumption.

4, Enhance thermal stability and durability

Alumina hollow ball bricks have excellent thermal stability, small rate of change of re-firing line, and can be used for a long time at a high temperature of 1750℃. Its closed pore structure effectively prevents heat transfer, extends the service life of the brick and reduces the frequency of kiln maintenance.

5, Optimize kiln structure and energy efficiency

Alumina hollow ball bricks can be used in high-temperature energy-saving inverted flame kilns, shuttle kilns and other equipment, by reducing the weight of the furnace, modifying the structure, saving materials and energy, to improve the overall energy efficiency of the kiln. Its high temperature resistance ensures stable operation in high-temperature kilns, which is suitable for petrochemical, metallurgical and other industries.

II. Alumina hollow ball in the filler through its unique physical and chemical properties, in a number of industrial fields play a key role, its core role includes high thermal insulation efficiency, weight reduction, fire anti-corrosion, sound absorption and noise reduction, etc., the specific analysis is as follows:

1. High thermal insulation efficiency, reduce energy consumption

Low thermal conductivity: the interior of alumina hollow ball is a closed pore structure, the air thermal conductivity is very low, making the overall thermal conductivity of the filler material significantly lower than that of the solid particle material.

Temperature gradient control: its thermal insulation performance helps to maintain the temperature uniformity inside the equipment, avoiding local overheating and prolonging the service life of the equipment.

2. Reduce weight and optimize structure

Low density: The bulk density of alumina hollow ball is only 1.1~1.5 g/cm³, which is about 1/3 of solid alumina particles. In automotive manufacturing and other fields, the use of hollow ball filling can significantly reduce the weight of the structure and improve fuel efficiency or load capacity.

Structural stability: Despite the low density, its high strength can still ensure the stability of the filling structure, avoiding the strength loss caused by weight reduction.

3. Fire and corrosion resistance for extended life

High temperature stability: the melting point of alumina is as high as 2050℃, the hollow ball can be used for a long time under 1800℃, which is suitable for metallurgy, ceramics and other high-temperature industrial environments.

Chemical inertia: excellent resistance to acid, alkali and other corrosive media, can protect the equipment from chemical erosion, reduce maintenance costs.

4. Sound absorption and noise reduction, improve the environment

Porous structure sound absorption: the pores inside the hollow ball can effectively absorb sound wave energy and reduce the spread of noise. Filling in building sound insulation materials or industrial noise reduction equipment can improve the working environment.

Frequency adaptability: By adjusting the size of the sphere and the rate of air holes, the design can be optimized for different frequency noise.