Abstract：The converter steel slag was crushed and screened for the magnetic separation experimental material. The experiment was carried out with the self-developed magnetic separator at different magnetic roller frequencies ( MRF) and magnetic separation distances ( MSD) . And a double- logarithmic fractal equation was established to study the fractal characteristics of the concentrate grade. The concentrate grade was calculated according to yield concept. The results show that: the mean value of fractal dimensions are 2. 25 and 2. 31 corresponding to MRF and MSD. The fractal characteristics are significant and magnetic separator has a stable sorting process. The influence to a sorting process is more obvious form MSD than MRF. Fractal dimension has a negatively quadratic function relationship with MRF, opposite to MSD. Through fractal characteristics analyses, the MRF and MSD are optimized as 44. 56 Hz, 11. 52 mm, and the concentrate recovery and concentrate rate are 66. 75%, 58. 46%, respectively.

Keyword：fine grain steel slag;dry magnetic separation;concentrate grade;fractal feature;fractal dimension;