Dense (Heavy) Media Separation (DMS)

Halyard’s team offers proven expertise in the design, engineering and operation of pre-concentration methods such as Dense (Heavy) Media Separation (DMS), which has traditionally been known for the recovery of diamonds and the cleaning of coal streams. In recent years, the DMS process has been employed effectively as a pre-concentration step to improve the recovery economics of various commodities including: platinum group metals, lead-zinc ores, nickel ores, lithium (spodumene) and gold bearing ores.

Benefits of Dense (Heavy) Media Separation:

  • Lowering the cut-off grade: In underground mining, DMS allows for the ability to utilize bulk mining methods such as long hole open stopping as opposed to shrinkage stoping and cut & fill since DMS helps minimize effects of dilution on the run of mine (ROM) ore.
  • Reduction of project capital by designing a process plant for a lower throughput since DMS concentrates the feed to the plant. Waste material is rejected by the DMS Plant and only mineralized ore is sent to the plant.
  • Reduction of operating costs and energy consumption for the project by using a smaller mill to process a large quantity of ROM.
  • The elimination of dilution and accidental waste in the ROM reporting to the flotation mill.
  • The potential provision of a competent backfill material from the DMS floats (waste) stream.

Ore Sorting

Ore sorting is suitable for several minerals and is capable of maximizing recovery or upgrading the ore.  Sorting technology analyzes each rock particle to identify unique physical and chemical properties and separates the particles by utilizing jets of compressed air. Halyard works alongside Tomra Sorting to provide a complete modular solution that allows clients to realize the economic benefits of laser or colour sensor-based sorting in any climate.

Benefits of Optical Sorting:

  • Powerful methods of pre-concentration or waste rejection.
  • Occurs early in the comminution process which reduces capital expenditure.
  • Decreases the use of consumables (water or electricity) per unit of metal produced.
  • Feed grade to the plant remains high.
  • Flotation and leaching recoveries are generally increased due to the higher head grade.
  • Opportunity to unlock value buried in stockpiles.

Bulk Sorting

It is more difficult to extract ore from low-grade deposits. Removing barren material earlier in the process can bring significant savings to operations. It also reduces the mine’s environmental footprint by lowering energy consumption, greenhouse gas emissions and overall water losses.

Benefits of Bulk Sorting:

  • Eliminates barren material early in the process.
  • Increases the grade of the ore in the next stage of processing.
  • Avoids feeding the plant with material that will cost more to process than its contained value.
  • More value with less impact, improving resource efficiency and sustainability.
  • Reduces the generation of tailings product.
  • In existing operations, production rate can be increased due to the increase in feed grade.