has been found to leave a certain amount of im- purities from precipitants and dyestuffs, and in some cases surplus precipitants, in the water phase. This would increase the need for fresh water renewal in case of recirculation or require a secondary treatment, e.g., using activated car bon. Flotation, filtration, and centrifugation have been tested for separation of precipitates[8], and a water quality of 2-3 mg/l of suspended solids can be achieved in first step separation by all techniques. An extra polish may be necessary for the reuse of the water.