Firing technology for energy-rich raw materials

Up to now, an increase in the porosity in heat-insulating backing bricks has been limited by the burn-out of the organic matter contained within the raw materials during a small temperature range in the preheating zone, leading to unusable energy release. This can sometimes lead to uncontrollability in the tunnel kiln. Within the framework of a research project Hans Lingl GmbH is developing a firing technology that guarantees safe process management when firing high-energy raw materials. The results achieved to date and the new Lingl PoroControl Technology are presented.

1 Project definition

The sought-after characteristics of porous backing bricks, such as low body density and high heat insulation, are achieved for instance with the addition of porosity-enhancing materials, such as paper-making sludge, sawdust or polystyrene during manufacture. Besides their effects on porosity, these additional materials also advance the exothermic reaction enthalpy, which means energy is released as a result of the burning of the porosity-enhancing materials. Altogether, this brings with it a reduction in the enthalpy of the raw materials or, in other words, the higher the...

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