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...

Related articles:

Issue 2018-6

New concept for improving heat transfer in tunnel kilns

Ceramic products have to be fired before they can be used, and tunnel kilns are well-suited for the job. To help optimize a kiln‘s energy efficiency, fans can be installed in the preheating and...

Issue 2016-8

Carry-over of raw material reactions in the preheating zone for energy utilization of carbon-containing body constituents

For firing high-thermal-insulation clay blocks, the raw materials must meet certain preconditions and the firing process fulfil certain requirements. These are necessary to make more efficient use of...

Issue 2015-8

Use of heat pumps in brick drying

For a brickworks with a production rate of 400 tonnes per day fired ware, the mixing water content of around 20 mass% necessary for pressing means that every day around 80 t water must be expelled...

Technical Paper

Causes and avoidance of damage on account of diffusion-dependent reactions in the preheating zone of tunnel kilns

1 Introduction The firing of heavy clay products is subject to a number of such limiting factors as expansion and contraction processes, endothermic and exothermic reactions and the conversion and...

Issue 2012-6

Ceric Technologies designs a supersized tunnel kiln for a Polish roofing tile plant

For its new Koscian facility, which will produce 30 mill. large-size clay roofing tiles (10 tiles/m2) and related accessories, the Belgian Etex Group has decided to entrust Ceric Technologies with the...