Drying Contraction Assessment of Ceramic Products Produced by Extrusion or Pressing Formulated with Sheep Wool Waste

The main aim of this paper was to evaluate ceramic products containing a percentage of ash from sheep wool waste through drying linear shrinkage from a small brickyard in Bagé - RS. The ash percentages used in the formulation were 0, 5, 10, 20 and 30%. Raw materials were analyzed by Energy Dispersive X - ray Fluorescence (XRF/EDX). The methods used to shape the ceramic products were vacuum extrusion and pressing. After shaping, the ceramic products were dried in laboratory conditions with an average temperature of 21°C for 3 weeks and later in an oven at 110°C for 48 h. The drying linear shrinkage test was performed according to the specifications of standard C-021/95, and its average results for all formulations were 8.2% and 0.7%, for the extruded and pressed products, respectively. The results of drying linear shrinkage were higher for the extruded products than for the pressed ones, showing that the addition of the ash from the sheep wool waste in the clay decreased the drying linear shrinkage in the extruded ceramic products.