... -stage pusher centrifuge has been sucessfully usen for folowing materials:Sodium Chloride, Sodium Sulphate, Sodium bichromate, Ammonium Sulphate, Boric Acid, Cellulose Acetate, Nitrocellulose, ... Urea, PVC, Potassium Chloride, Potas- sium Sulphate, Potassium Carbonate, ...