As an emerging multi-functional material, fly ash float beads are used as the preferred material for the production of lightweight insulation materials because of its light weight, heat insulation, acid and alkali resistance, non-toxicity, no burning and no odor. And explore a reasonable production process will open up a new way for the comprehensive utilization of fly ash, and will have a positive effect on the development of the kiln industry. Refractoriness of Lightweight floating bead insulation brick is 1100~1300℃. Thermal conductivity is 0.105~0.127W(m·K).
The pulverized coal is in a suspended combustion state in the furnace, and most of the combustibles in the granules are burned out in the furnace, and the high temperature causes the pulverized coal particles to become molten, and under the strong disturbance,the initial temperature of the near super fluid material and the cooling rate are the key factors in the formation of the drift beads. The melt of the substance with large particle size is blown into a bubble under the impact of the fluctuating hot air current. As the carrier medium of the bubble, when the temperature of the flue gas is reduced to a certain value, the bubble cools and contracts to form a floating bead.
The floating bead is a glass material. Under normal temperature, its reflection coefficient to temperature is about 20%. As the temperature increases, the reflection coefficient increases. The gas enclosed in the beads is cooled and contracted during the formation of the floating beads, and a certain degree of vacuum is generated inside the beads. Therefore, the floating beads have excellent thermal insulation properties, and the thermal conductivity at normal temperature is 0.025-0.033 W/(m·k).
This issue mainly introduces the floating beads in lightweight insulation bricks, hope this can bring help to the kiln builders. In the next issue, we will continue to introduce the formation of foam in lightweight floating beads insulation bricks. Please stay tuned!
