Ore from the Pine Point Project (PPP) R190 deposit will produce significantly upgraded concentrates through crushing and the Dense Media Separation (DMS) process.
The zinc, lead and iron sulphides at the PPP are present as veins, mass sulphides occurrences and remnants in a limestone host rock association. The dilution in the run of mine (ROM) ore will be a mixture of dolomites and limestone which has a significantly lower specific gravity (s.g.) than the sulphides. The Dense Media Separation (DMS) process is able to take advantage of the significant difference in the specific gravity (s.g.) of the liberated host rock by removing it from the crushed ROM ore with minimal loss of sulphides.
Coarse material will be concentrated through small material DMS to a concentrate containing zinc and lead sulphide minerals. The fine-sized feed will be concentrated through gravity separation and combined with DMS product. The DMS waste (floats) and gravity separation gangue discharge will be chemical and sulphide free. Water and dense media will be reclaimed for re-use in the process plant.
The washed DMS “float” product will be conveyed to a storage pile and subsequently used to backfill mined-out openings and stopes underground. The washed DMS “sink” product will be processed further, stockpiled and hauled by truck to the railhead at Hay River. The washed fines will be dewatered and then stockpiled for subsequent mixing with the DMS “sink.”
The DMS process will save capital, operating costs and energy consumption for the project, as well as give the project a longer operating life.
Dense Media Separation Advantages
- Proven at the Nanisivik Mine
- Currently used by several mining operations in Tennessee
- Doubles the grade by scalping off 50% of the gangue
- Reduces concentrate shipping and transportation costs
- Reduces size of milling circuit