Gravity Separation of Particulate Solids in Turbulent Fluid Flow

The separation characteristics of particles’ settling velocity, size, density, and shape are introduced, and the equivalent settling condition for laminar, transition, and turbulent flow are explained. A similarity model of particle transport in a turbulent flow field is briefly discussed. Typical operation principles in separation devices for counter current and cross-flow separation are presented. The separation function, cut point, sharpness, and separation stage utilization coefficient are determined to assess the efficiency for process sequences for multistage turbulent cross-flow separation. Satisfactory to very good results were achieved in the difficult separation of a partially liberated aggregate consisting of hardened cement paste rubble with sharpness from 0.66 to 0.94 at separation stage utilization coefficients of 7 to 87%. Specific mass flow rates of 3 to 16 t/(m² · h) and mass related energy consumption of 0.2 to 8 kWh/t were obtained.