Dense Medium Separation Ep Calculator
Mineral processing & coal beneficiation: Calculate cut point density (ρ₅₀), Ecart Probable Moyen (Ep), imperfection index, and Tromp partition sharpness.
DMS Cyclone Operating Parameters
Separation Efficiency & Tromp Metrics
Frequently Asked Questions
What is Ecart Probable (Ep) in Dense Medium Separation?
Ecart Probable (Ep) is the standard international metric for separation sharpness in gravity concentration. Calculated as (ρ₇₅ - ρ₂₅) / 2 from the Tromp partition curve, an ideal separation has Ep = 0, whereas modern heavy-media cyclones achieve Ep values between 0.020 and 0.045 g/cm³.
Why does a dense medium cyclone cut at a higher density than the feed medium?
Due to centrifugal acceleration inside the cyclone, fine heavy media particles (magnetite or ferrosilicon) concentrate outward toward the underflow cone. This creates a denser internal fluid core than the incoming feed slurry, causing the effective separation cut density (ρ₅₀) to be 0.05 to 0.15 g/cm³ higher than the feed medium density.
What is Near-Gravity Material (NGM) and why is it dangerous?
Near-Gravity Material is the percentage of raw ore with a specific gravity within ±0.10 g/cm³ of the operating separation cut point. If NGM is high (>15–20%), the particles have almost zero buoyant driving force and take longer to separate, leading to misplaced material and extreme sensitivity to media density fluctuations.