Project Overview
WSHT Mining Group was awarded a significant expansion project at an existing copper mining operation in the Karaganda region of Kazakhstan. The expansion added a new 25,000 tpd grinding and flotation circuit, increasing the concentrator's overall capacity by 60% to 40,000 tpd.
Background
The client operates one of Kazakhstan's largest copper mines, producing copper concentrate for export to smelters in Russia and China. With copper prices rising and existing reserves requiring more intensive processing, the client sought to expand capacity to exploit the remaining ore body economically.
Project Scope
New Grinding Circuit:
- SAG mill 10.97m × 5.4m (28 MW) — one of the largest installed in Central Asia
- Ball mill 7.3m × 11.0m (15 MW) — operating in closed circuit with hydrocyclones
- Recycle crusher for pebble recycle duty
- Complete mill feed and product handling systems
New Flotation Circuit:
- Rougher, scavenger and cleaner flotation cells (total 24 cells)
- Column flotation cells for final cleaning
- Reagent dosing and mixing systems
- Concentrate handling and thickening
Supporting Systems:
- Tailings thickening and pumping to existing tailings storage facility
- Process water system upgrades
- Power supply and distribution
- Control system integration with existing plant
Copper Concentrator Expansion — Kazakhstan
Technical Challenges
Pebble Crushing Integration: The existing SAG mill discharge screen was modified to allow pebble recycle to a dedicated cone crusher, with crushed pebbles returned to the SAG mill feed.
Existing Operations Continuity: The expansion was designed to allow construction and commissioning without disrupting existing plant operations — achieved through careful sequencing and temporary facilities.
Cold Climate Design: The plant is located in a region with extreme temperature variations (-40°C winter to +40°C summer). All equipment and systems were specified for this operating environment.
Equipment Supply
- SAG Mill 10.97m × 5.4m with dual-pinion 28 MW drive
- Ball Mill 7.3m × 11.0m with 15 MW gearless drive
- HP4 Recycle Cone Crusher
- SF-28 Mechanical Flotation Cells (24 units)
- Column Flotation Cells (4 units)
- 35m Diameter High-Rate Thickeners (2 units)
- Complete process automation system
Performance Results
- Design Throughput: 25,000 tpd (new circuit)
- Actual Throughput: 26,500 tpd achieved during ramp-up
- Copper Recovery: 88% overall (design 86%)
- Concentrate Grade: 28% Cu (design 25%)
- Expansion Completion: 24 months from contract to commercial operation
The successful execution of this project established WSHT as a trusted EPC partner for major mining companies operating in Central Asia.
