For low-grade, complex copper oxide deposits, Metalcess provides an integrated EPC turnkey solution for wet copper processing, comprising heap leaching – leachate recycling and concentration – solvent extraction (SX) – electrowinning (EW), focusing on the efficient, low-cost development of small- to medium-scale copper deposits.

Particularly suitable for:

·Copper oxide ores with a copper grade below 1%

·Easily leachable minerals such as malachite and azurite

·Complex ore bodies with high alkaline gangue content where conventional beneficiation and smelting are economically unviable

1. Heap Leaching System: The Threshold for Economic Viability of Low-Grade Ore

For low-grade copper oxide resources, the heap leaching process is the key route to achieving economical recovery on a large scale. Metalcess provides comprehensive engineering design and supply for heap leaching systems, including:

·Crushing—granulation—heap construction system design

·Engineering of impermeable heap storage areas and leachate collection systems

·Optimised design for acid spray distribution and leaching uniformity

·Optimisation of heap leachate flow and reaction kinetics

·Adaptation to ore systems with high clay content and highly alkaline gangue

By optimising the distribution of heap leach solution and leaching pathways, efficient primary copper leaching is achieved, providing a stable source of concentrate for subsequent SX-EW processing.

2. Leachate Circulation and Enrichment System: Increasing the Economic Concentration of Copper Ions

To address the issues of ‘low copper concentration and significant fluctuations in impurity levels’ in leachate from low-grade ore, Metalcess has established a closed-loop enrichment system:

·Design of the leachate recovery and recycling system

·Control of lean solution re-acidification and re-spraying circulation

·Buffering and homogenisation tank system for rich solution

·Control of impurities such as iron, aluminium and silicon, and optimisation of sedimentation

·Modelling of leachate equilibrium and system stability

Through systematic liquid-phase management, the concentration and stability of copper ions entering the extraction stage are enhanced, significantly reducing the energy consumption per unit of SX-EW.

3. Solvent Extraction (SX) System: The Core of High-Efficiency Copper-Selective Enrichment

Metalcess possesses independent and comprehensive engineering design capabilities for copper solvent extraction, covering small- to medium-scale SX production lines.

Core technical capabilities include:

✔ Design of mixing and clarification systems

·Design of primary pump-mix tanks

·Design of secondary mechanically stirred mixing tanks

·Multi-stage counter-current extraction/strip process configuration

·Optimisation of O/A ratio and phase separation kinetics

✔ Key engineering design capabilities

·Calculation and simulation of agitation power and impeller parameters

·Emulsification control and phase separation interface design

·Organic phase loss control and recovery system design

·Optimised flow field design for settler tanks

·Optimisation of anti-carryover structures and flow patterns 

Through refined fluid engineering design, the following are achieved:

· High extraction efficiency

· Rapid phase separation

· Stable organic phase circulation

· Operation with low organic loss

4. Electrolytic Deposition (EW) System: Stable Production of High-Purity Cathode Copper

Metalcess offers comprehensive EPC design capabilities for complete electrolytic copper production facilities, including:

·Electrolytic cell (EW cell) system design

·Current density and electrical efficiency design

·Electrolyte circulation and temperature control systems

·Additive control and hydrogen evolution suppression design

·Cathode stripping and automated handling systems

The system is capable of consistently producing:

·99.99% LME Grade A electrolytic copper

·Cathode plates with a stable grain structure and low impurity content

5. Metalcess’s EPC Turnkey Contracting Capabilities

As an EPC service provider specialising in hydrometallurgical copper projects, Metalcess offers one-stop engineering solutions from ore to cathode copper

✔ Process package design capabilities

·Full-process integration of heap leaching + solvent extraction (SX) + electrowinning (EW)

·Customised process design for copper oxide ores

✔ Core Equipment Engineering Capabilities

·Design and manufacture of mixer-settler systems

·Integrated design of electrowinning systems

·Engineering of leachate recirculation systems

✔ Project Delivery Capabilities

·EPC turnkey contracting for small- to medium-scale hydrometallurgical copper projects 

·Modular plant design

·Process commissioning and support for achieving full production capacity

6. Project Application

This solution is particularly suitable for:

·Low-grade copper oxide ore development projects (<1% Cu)

·Development of dispersed mineral resources

·Small- to medium-scale copper hydrometallurgical projects (SX-EW)

·Marginal ore bodies where conventional pyrometallurgical processing is uneconomical

·Tailings re-processing and secondary resource recovery projects