Gold CIP Process: Principles, Flowsheet, Plant Design, and Best Practices

1.Gold CIP Introduction

Carbon‑in‑Pulp (CIP) is an established, efficient method for recovering gold from cyanide-leached slurry. It works best on low-grade and oxidized ores, flotation tailings, and gravity-tailings due to its simplicity and low capital cost

2. Gold CIP Advantages and Constraints

Gold CIP Advantages:

 High gold recovery (>90%) for fine and low-grade ores

 Lower investment than flotation or heap-leach plants

 Modular and scalable for expansion

Gold CIP Constraints:

 Uses cyanide — must maintain pH \~10.5–11.5 and manage effluents;

 Not ideal for high-copper ores; CIL or flotation may be better

3. Gold CIP Process Flow and Unit Stages

4. Gold CIP Plant Design & Equipment

 Leach & adsorption circuits: 5–8 tanks with agitators

 Screens & cyclones: Remove gangue and regulate pulp density

 Desorption units: Pressure- or heat-enhanced tanks

 Electrowinning cells: For gold recovery

 Smelter furnace: Converts cathode mud to bullion

 Automation & controls: Modern systems enhance recovery and safety (e.g., Xinhai Mining’s smart modules) 

5. Gold CIP Operational Parameters & Optimization

 Cyanide concentration: 0.01–0.1%, adjusted per ore type

 pH control: Maintain 10.5–11.5 to prevent HCN formation

 Oxygen levels & agitation: Crucial for cyanide efficiency

 Residence time: Balanced for cost vs recovery

 Carbon selection & screening: Size/grade critical for adsorption rate

6. Gold CIP Environmental, Safety & Economic Considerations

 Cyanide detoxification: On-site treatment to meet safety standards

 Tailings handling: Includes filtration, solidification, and freeing heavy metals

 Wastewater treatment: Includes filtration, chemical neutralization, possible heavy-metal removal

 Cost evaluation: CIP offers low CAPEX; smart designs (e.g., steel structure plants) reduce build time/money

7. CIP vs CIL – Which One?

 CIP leaches first, then adsorbs — simpler, flexible, but slightly slower

 CIL combines adsorption during leach — faster, often higher recovery; better for low-resistance ores 

Conclusion

CIP is a proven, flexible method for gold recovery from low-grade, oxidized, or tailing ores. When correctly designed and controlled, it delivers high recovery with modest capital cost. For best outcomes:

1. Optimize comminution and reagents

2. Implement robust pH, cyanide, oxygen controls

3. Ensure effective carbon handling and regeneration

4. Prioritize cyanide detox and tailings safety

5. Evaluate whether CIP or CIL suits your ore and throughput needs