Abstract
	The ceramic suspensions containing of 60 - 65 wt. % solids react markedly on concentration of deflocculants. The deflocculant-electrolyte is added into the mass to decrease the viscosity of slurry at an amount of 0,2 - 0,4 wt. %. Any small difference: inaccurate dosing of deflocculants or quality of water often causes troubles at the plant.
	The first step before the test of electrolyte effect is the verification of water quality at the plant used for preparation of ceramic suspensions. The work is focused on mapping of ion concentration changes of Na+, K+, Mg2+, Ca2+, PO43– and SO42– in the waste water and waste slurry. The quality of cleaned recycled water has been observed for more than one year. The fluctuation of pH value of water was not significant. The average value of pH = 6.4 (? 0.2) of recycled water corresponds with well water (average pH = 6.3). The results of water analysis suggest ion exchanges caused by flocculating agent (polyaluminium chloride) during the flocculation process. The Na+ concentration decreased, the Ca2+ concentration increased and the PO43–, SO42– are partly precipitated, deposited. In consequence of flocculation the concentration of Ca2+ increased two times and concentration of Na+ went proportionally down. The concentration of alkaline earth metal ions in the cleaned recycled water was 7 times higher, the concentration of alkaline earth ions was 1.5 times higher and Cl– was 6 times higher than in the well water. How the differences of ion concentration in water influenced the fluid ceramic suspensions, viscosity, thixotropy and sedimentation is the object of the following work.