In Tanzania, a country rich in gold resources in Africa, a rock gold mine (oxide ore) project with a daily processing capacity of 200 tons has been put into production efficiently with the advanced CIL (carbon-in-leach) process, with a gold recovery rate exceeding 92%, becoming a model for oxide ore development in East Africa. This article will deeply analyze the process flow, technical highlights and operating results of the project.

1. Project Background
The mining area is located in the gold mineralization belt of Tanzania, where the ore is mainly oxidized and the gold deposit is complex, with high mud content and a small amount of accompanying sulfides. Customer requirements:
- Designed daily processing capacity of 200 tons, adapted to the characteristics of high clay oxide ore
- Environmental compliance, in line with local strict emission standards
- Shorten construction period, control investment costs
2. Process Design
CIL method as the core, customized gold extraction plan for ore characteristics, using "crushing-grinding-leaching-adsorption-desorption-electrolysis" full process CIL process to achieve efficient gold recovery:
Crushing and screening system
- Coarse crushing: jaw crusher (feed size ≤400mm → ≤75mm)
- Fine crushing: cone crusher + vibrating screen closed-circuit circulation, ensuring that the particle size entering the mill is ≤15mm
Grinding and classification system
- Wet grid ball mill + spiral classifier, grinding fineness reaches -200 mesh accounting for 85%
- Add dispersant to solve the mud encapsulation problem and improve the gold leaching rate
CIL leaching and adsorption system
- 7-stage series leaching tank (first 2 stages pre-leaching, last 5 stages CIL), total residence time 36 hours
- Activated carbon countercurrent adsorption, gold-carrying carbon grade reaches 3000g/t
- Cyanide concentration 0.05%, pH value 10.5-11.5, precise reagent control
Desorption electrolysis and smelting
- High temperature and high pressure desorption process, desorption rate >98%
- Electrolytic deposition to obtain gold mud, and smelting to produce gold ingots with a purity of 99.5%

3. Technical Highlights
Efficient pretreatment process
- Add a washing screen to remove clay and avoid No clogging of grinding system
- Cyclone classification + thickener dehydration, optimize the pulp concentration to 40-45%
Energy-saving and consumption-reducing design
- The ball mill adopts variable frequency control, reducing energy consumption by 15%
- The tailings dry discharge system achieves a water resource recycling rate of >85%
Intelligent control system
- Full process DCS automatic control, real-time monitoring of key parameters
- Online adjustment of ORP value in the leaching section to ensure leaching stability
4. Environmental Protection and Sustainability
- Zero emission treatment: tailings are dry piled after filter pressing, and the filtrate is reused in the production process
- Hazardous waste control: cyanide detoxification system ensures that wastewater meets the discharge standards
- Community win-win: more than 60% of local employees are employed, and supporting public welfare facilities are built
With its high process adaptability and fast return on investment, the CIL production line provides a replicable solution for the development of similar oxide ores in Tanzania and Africa. We provide "one-stop service" from mineral processing tests, engineering design to operational support to help global customers dig gold in Africa.








