The energy consumption of iron and steel production accounts for about 10 % of the total energy consumption in China. energy conservation in iron and steel industry will bring fundamental benefits to the cause of energy conservation and environmental protection in the whole society. Heat insulation material is an important component of steel production equipment, which has a great impact on equipment energy consumption. Nano thermal insulation board is considered as the best known thermal insulation effect of high temperature materials, has been gradually accepted and applied in steel-making equipment, greatly reduce the surface temperature of equipment, significantly reduce the heat loss of equipment, improve product quality, improve production efficiency, reduce the production cost of steel.
Introduction of nano heat shield
The thermal insulation effect of the nano thermal insulation board is 2 - 10 times of that of the traditional thermal insulation material, and the nano thermal insulation board is a novel material which is developed based on the microporous thermal insulation principle and mainly comprises superfine silicon dioxide powder with the diameter of 7 - 20 nm, a mixed thermal radiation shielding material, high-strength superfine fiber, high-temperature shrinkage resistant material and the like, and is pressed by a special process.
The surface of the product is covered with glass fiber cloth, aluminum foil, plastic film, etc., and the common forms are flat plate type, felt type, roller shutter type, block type, etc. Flat type for flat wall or arc is not too big furnace wall, felt type can be used for steel ladle and other space has strict restrictions on equipment, roller shutter type is mainly used for piping system.
The nano heat insulation board has good machinability and increases the strength of the material, is convenient to install and use, and is easy to cut and form. The nano heat insulation board can maintain very low thermal conductivity in a wide temperature range, can be used under the working condition that the instantaneous temperature is 1100 deg c, and can maintain the long-term service temperature at 1000 deg c,
The use temperature and thermal conductivity are the two most important technical indicators of nano heat insulation board. the maximum use temperature of nano heat insulation board is the indicator to measure the high temperature performance of the product. at this temperature, the material can be used for a short time, and the linear shrinkage rate is less than 2 %. when designing the thickness of heat insulation layer, it should be avoided to be too thick, so as to ensure that the hot surface temperature of heat insulation material is not higher than the maximum use temperature, and the general design redundancy is 100 ℃.
Thermal conductivity is an important index to measure the thermal insulation performance of materials at high temperature. Due to the fact that the diameter of the micropores formed in the material is smaller than the average free stroke of air molecules, the collision heat transfer between the molecules is inhibited, and due to the action of the heat radiation shielding component, the material can achieve lower heat conductivity than static air at high temperature.