Hydrometallurgy Course

Lesson 1 • Aqueous Chemistry Fundamentals

Introduces ionic equilibria, activity coefficients, and speciation in metal-bearing solutions. These concepts underpin leaching and solution chemistry throughout the course.

Lesson 2 • Introduction to Metal Extraction

Covers the historical development and industrial significance of aqueous metal recovery. Provides context for all subsequent processing steps covered in the course.

Lesson 3 • Thermodynamics of Aqueous Systems

Applies Gibbs energy and Pourbaix diagrams to predict metal dissolution behavior. Students use these tools to assess reaction feasibility before process design.

Lesson 4 • Kinetics of Dissolution Reactions

Examines rate-controlling mechanisms including diffusion, surface reaction, and mixed control. Kinetic understanding guides leach circuit design and optimization.

Lesson 1 • Biological Oxidation Methods

Introduces bioleaching and biooxidation using acidophilic bacteria and archaea. Microbial mechanisms are linked to sulfide mineral oxidation kinetics.

Lesson 2 • Agglomeration and Heap Preparation

Covers ore agglomeration with acid or cement binders to improve heap permeability. Proper agglomerate strength and size distribution are critical for heap leach performance.

Lesson 3 • Roasting and Calcination

Examines oxidative, sulfating, and chloridizing roasting to convert refractory minerals. Roast product mineralogy determines subsequent leach reagent selection.

Lesson 4 • Comminution for Leaching

Covers crushing and grinding to achieve target liberation and surface area for leaching. Particle size distribution directly controls leach rate and reagent consumption.

Lesson 1 • Alternative Lixiviant Systems

Introduces thiosulfate, thiourea, halide, and glycine leaching as cyanide alternatives. Students evaluate trade-offs in cost, selectivity, and environmental impact.

Lesson 2 • Acid Leaching Systems

Covers sulfuric, hydrochloric, and nitric acid dissolution of base metal sulfides and oxides. Acid selection criteria are linked to mineralogy and downstream processing requirements.

Lesson 3 • Leach Solution Management

Addresses solution bleed, impurity buildup, and reagent replenishment strategies. Effective solution management sustains leach efficiency and reduces operating costs.

Lesson 4 • Alkaline and Cyanide Leaching

Examines cyanidation for gold and silver and carbonate leaching for uranium and vanadium. Reagent stability, consumption, and selectivity are analyzed in detail.

Lesson 1 • Vat and Percolation Leaching

Covers static vat leaching and percolation systems for coarse, permeable ores. Solution channeling and ore bed management distinguish these from agitated systems.

Lesson 2 • Reactor Modeling and Scale-Up

Applies residence time distribution theory and population balance models to scale laboratory data. Scale-up factors for mixing, mass transfer, and heat transfer are quantified.

Lesson 3 • Pressure Leaching Reactors

Addresses horizontal and vertical autoclave design for elevated temperature and pressure leaching. Materials selection, sealing, and safety systems are integral to autoclave operation.

Lesson 4 • Heap and Dump Leaching Systems

Covers design, irrigation, and solution collection for heap and dump leach operations. Hydrological modeling and solution management are central to heap performance.

Lesson 1 • Residue Handling and Disposal

Covers tailings characterization, dewatering, and safe disposal of leach residues. Residue management practices minimize environmental impact and meet regulatory requirements.

Lesson 2 • Clarification and Polishing

Addresses removal of fine solids and colloidal particles from pregnant leach solutions. Clarified solutions meet purity requirements for downstream solvent extraction or electrowinning.

Lesson 3 • Thickening and Sedimentation

Covers gravity sedimentation theory and thickener design for leach pulp clarification. Flocculant selection and dosage optimization are critical for underflow density and overflow clarity.

Lesson 4 • Countercurrent Decantation Circuits

Covers CCD circuit design for washing dissolved metal from leach residues using minimum wash water. Stage efficiency and wash ratio calculations are applied to circuit optimization.

Lesson 1 • Solvent Extraction Circuit Design

Covers mixer-settler and pulsed column design for extraction, scrubbing, and stripping stages. Organic-to-aqueous ratios, stage efficiency, and crud management are optimized.

Lesson 2 • Solvent Extraction Principles

Examines extractant chemistry, diluent selection, and phase equilibria for metal transfer. Distribution coefficients and separation factors quantify extractant performance.

Lesson 3 • Selective Precipitation Methods

Covers pH adjustment, sulfide, and hydroxide precipitation to remove impurity metals. Precipitation sequence and reagent dosage are optimized for selectivity and downstream processing.

Lesson 4 • Ion Exchange Circuit Design

Covers fixed-bed, moving-bed, and resin-in-pulp circuit configurations for metal recovery. Column sizing, breakthrough curves, and elution profiles guide circuit design.

Lesson 1 • Final Refining and Product Quality

Covers smelting, casting, and chemical refining of electrodeposited or precipitated metals. Product specifications and quality assurance methods are applied to final metal output.

Lesson 2 • Cementation and Reduction

Covers metal displacement by cementation on iron, zinc, or aluminum and chemical reduction. Selectivity, reagent consumption, and product purity are evaluated.

Lesson 3 • Electrowinning Cell Design

Examines electrode materials, cell geometry, electrolyte flow, and current distribution. Cell design parameters are optimized for deposit quality and operating cost.

Lesson 4 • Activated Carbon Adsorption

Addresses carbon-in-leach, carbon-in-pulp, and carbon-in-column circuits for gold recovery. Elution, electrowinning, and carbon regeneration complete the recovery cycle.

Lesson 1 • Plant Commissioning and Ramp-Up

Covers pre-commissioning checks, water commissioning, and ore introduction during plant start-up. Ramp-up planning minimizes time to design throughput and recovery.

Lesson 2 • Reagent and Utility Consumption

Quantifies reagent, water, and energy consumption across the integrated plant. Consumption benchmarks guide operating cost estimation and sustainability targets.

Lesson 3 • Capital and Operating Cost Estimation

Covers factored cost estimation, equipment sizing, and operating cost buildup for hydrometallurgical plants. Economic indicators including NPV and IRR are calculated for project evaluation.

Lesson 4 • Flowsheet Development and Selection

Covers systematic flowsheet synthesis from ore characterization through final metal product. Decision criteria for unit operation selection are applied to case study ores.

Lesson 5 • Process Control and Optimization

Introduces instrumentation, control loops, and advanced process control for hydrometallurgical circuits. Optimization strategies reduce reagent cost and improve metal recovery.