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Niederpleis clay pit/St Augustin
In the Rhein-Sieg District near Bonn is the Niederpleis clay pit, situated directly next to the A 3/A 560 motorway junction. Clays have been won here since 1893, originally for making bricks, but later for the production of tiles. Now the pit belongs to the Rhein-Sieg-Abfallwirtschaftsgesellschaft mbh RSAG, which has been winning clays here for sealing its landfills for 35 years. But the deposit is so big that only a small part of it is needed for sealing. The RSAG wants to supply the larger part of the clays to the ceramics industry and has enlisted as a partner the Arno Witgert clay mining company based in Herschbach, Upper Westerwald. Arno Witgert will not only be responsible for sales of the clay, but also contribute its know-how in the clay winning, storage and quality control. The RSAG’s nearby composting plant was made available for the covered storage and loading of the clays. Thanks to the short transport distances and available extraction, storage and loading equipment, extremely cost-efficient operation is possible.
The pit area covering over ten hectares, mostly untouched, still holds approx. 1.5 mill. tonnes highly plastic clay. It is an illitic-kaolinitic clay with a predominantly kaolinite content of high plasticity and buff firing colour.
Advantages
› high and long-term availability
› low raw material costs
› high plasticity
› very fine-grained
› high dry MoR
› good sintering behaviour
› unusual buff fired colour
Possible applications
› Body clay for buff-coloured clinkers and facing bricks as well as for stoneware pipes
› Fine-grained, plastic component for backing bricks and roofing tiles
› Additive for increasing the MoR of clay bodies for floor tiles
Arno Witgert’s blending plant in the nearby Westerwald enables blending of the clay from Niederpleis with the typical Westerwald clays and the production of standardized blends with defined properties, to combine the advantages of the two raw material deposits. So, for example, light-firing tile blends with high dry MoR were developed.
Dipl.-Ing. (FH) Michael Liebig (Fa. Witgert)
