Pressure leaching and oxidation

Author(s) T. Krumins, K.S. Fraser, R. Frischmuth, M. Pearson
SME Mineral Processing & Extractive Metallurgy Handbook, Chapter 10.6 February 1 2019


Pressure leaching and pressure oxidation are hydrometallurgical processes applied to the extraction of many metals.The processes occur above atmospheric boiling temperature, require a sealed reactor vessel, and often operate in highly corrosive and oxidizing environments. Pressure leaching and pressure oxidation have been applied to a broad range of processes over a wide range of conditions and include similar features such as

  • Slurry feed: Chemical conditioning, preheat, and highpressure pumps; 
  • Reactor vessel: Digester and leach or oxidation autoclave;
  • Pressure letdown: Flash vessel;
  • Off-gas handling: Atmospheric condenser and scrubber;
  • Ancillary systems: Acid, oxygen, air, steam, and water injection systems, and an agitator seal system.