Process for producing ceramic bodies from sediments, in particular mud and silt

摘要

The process described for producing ceramic bodies from sediments, in particular mud and silt, comprises the following steps: a) a part of the sediment is predried to as low as possible a residual moisture content and the dry material (t) thus obtained is subsequently fired to give a raw chamotte (a), b) a further part of the sediments is predried to a comparatively high residual moisture content and the dry material (b) thus obtained is mixed with the raw chamotte (a) (advantageously in a ratio of one part by weight of raw chamotte to one to two parts by weight of dry material), with the residual moisture content in the dry material (b) being set so that the mixture (c) has a moisture content of about 6-10% by weight. c) the mixture (c) is shaped by conventional means and is subsequently fired at ceramic firing temperatures. This process makes it possible for the material to be processed on conventional dry presses to give shaped parts which can then be fired in a conventional manner. This virtually eliminates shrinkage on drying and minimizes the shrinkage on firing, so that at a total shrinkage of about 3-4 % it is possible to produce brick products having accurate dimensions and even large size. The process is preferably carried out in a countercurrent furnace, i.e. a tunnel kiln having two countercurrent channels, without supply of primary energy. A countercurrent furnace allows the optimum utilisation of the... in the sediments... Original abstract incomplete.