The centrifugal granulation technique has the potential for high value-added resource utilization and simultaneous waste heat recovery from blast furnace (BF) slag. Particle size characteristics which provide guide for the determination of operation conditions, are main criterion for assessing the system performance. However, limited by the harsh experimental conditions, no correlation formula of real BF slag particle size has been proposed. In this paper, a three-dimensional model was constructed to describe granulation behavior of liquid slag via rotary disk, with discussion given to the ligament fragmentation detail, characteristic time, particle size distribution and number distribution. Notably, an expression combined with dimensionless parameters was developed to predict the mean diameter of real BE slag granules. The flat disk and arc-edge disk were found to be appropriate for practical application due to their ability to obtain small slag particle size and to suppress slag wool formation. (C) 2020 Elsevier B.V. All rights reserved.