In the present thesis, different spent refractory materials were investigated (basic/acidic, fired/unfired) with regard to their processability. The extensive experimental investigations included comminution trials, assessment of the comminution products and sorting. The comminution tests of spent refractory bricks using a laboratory jaw crusher were conducted using Optimized Comminution Sequence method. The test sequence consisted of three comminution steps: the first comminution step had a target product size below 40 mm, the second and the third comminution steps had a product size below 20 and 10 mm, respectively. In addition to comminution tests with conventional method, High Voltage Breakage investigations using the Selfrag laboratory unit were performed. As feed the product of first conventional comminution step was used. The tests of High Voltage Breakage were designed to replace the second and third comminution steps of the conventional comminution. The energy consumption, particle size distributions of the products and energy efficiency were compared. The studies were supported with XRD-analysis, XRF-analysis, mineralogical assessment, and fractional analysis. Sensor-based sorting investigations of the comminution products using visible and ultraviolet spectrums were conducted to evaluate the possibility to sort the corresponding spent refractories.