In practice, the advantages of high-quality hydrocyclone separation are often restricted due to varying feed suspension properties, solids concentrations and particle size distributions. Control systems of large hydrocyclones are usually fitted with controllable underflow nozzles, which is not practical for small hydrocyclone batteries. Therefore, a new control system for a battery of hydrocyclones with a nominal diameter of 150 mm seas invented at the LUR in co-operation with AKW Apparate and Verfahren [Computergesteuerte Hydrozyklonbatterie erfolgreich eingesetzt, Aufbereirungstechnik 42 (2001) Nr. 12, Th. Neesse, F. Donhauser, Advances in the theory and practice of hydrocyclone technique. Proceedings of the XXI International Mineral Processing Congress. Rome, Italy Juli 2000. V.A., p A4 - 74., Th. Neesse, F. Donhauser, M. Schneider, Computer-controlled hydrocyclone battery, Advances in Filtration and Separation Technology, Science and Technology of Filtration and Separations for the 21st Century. Editors Shiao-Hung Chiang and Samuel E. Lee. American Filtration and Separation Society, Vol. 15, Pittsburgh, 2001., M. Schneider, Th. Neesse, F. Donhauser, Mechatronik fur eine Hydrozyklon-batterie, Aufbereitungstechnik 40 (1999) Nr. 2, S. 79 - 83 AT., M. Schneider, T. Neesse, B. Schricker, F. Donhauser, Overflow-control system for a hydrocyclone battery. Proceedings of the International Congress for Particle Technology PARTEC 2001. Nurnberg, March 2001] This process was developed for bentonite slurry regeneration associated with tunnel excavation using bentonite slurry as a transport aid and lubricant. (C) 2004 Published by Elsevier B.V.