1. Home
  2. Dense Media Separati ...

Engineered DMS circuits for efficient pre-concentration

BROCHURE

Contact YPT for a detailed information about Dense Media Separation.
Brochure Request

YPT Quality Management System

For detailed information about YPT Quality Management System
YPT Quality

YPT Process Equipment Factory

For detailed information about YPT Process Equipment Factory
YPT Factory

Density differences used as a powerful design tool

Dense Media Separation

Dense Media Separation (DMS) is a gravity-based separation method that uses a slurry of finely ground dense material, typically magnetite or ferrosilicon, to separate particles according to their specific gravity. Crushed ore screened into a suitable size range is mixed with the dense medium and exposed to gravitational or centrifugal forces in DMS cyclones or baths. Particles denser than the medium report to the “heavy” product, while lighter gangue forms the “light” product or waste stream. By rejecting low-value material at relatively coarse sizes, DMS reduces the mass load on grinding, flotation and leaching circuits, saving energy, water and installed capacity. It also improves downstream stability by delivering a more consistent, higher-grade feed to the rest of the plant, especially where ore variability is significant.

Typical ores and applications

  • Base metal ores

    Pre-concentration of Cu, Pb, Zn, Ni ores where dense sulphide minerals can be separated from lighter silicate gangue.

  • Diamonds and gemstones

    Recovery of dense, diamond-bearing material from kimberlite or alluvial deposits ahead of final recovery circuits.

  • Iron ore and manganese

    Upgrading of Fe and Mn ores by rejecting low-density, silica- and clay-rich gangue.

  • Chromite and other high-SG minerals

    Concentration of chromite and certain tungsten or heavy mineral assemblages where specific gravity contrast is strong.

  • Coal and selected industrial minerals

    Beneficiation of coal by rejecting high-density, ash-forming material, and some industrial minerals where density differences are exploitable.

Typical position in the flowsheet

  • Downstream of primary and secondary crushing and screening

    once suitable size fractions for DMS treatment and by-pass are prepared.

  • After washing and desliming stages in clay- or fines-rich ores

    where slime removal is needed to stabilise dense medium behaviour.

  • Upstream of grinding, flotation and leaching

    as a pre-concentration step that removes barren or waste fractions.

  • In combination with post-DMS screening, washing, thickening and dewatering

    to deliver clean products and controlled waste streams.

  • Integrated with stockpiling and plant feed management

    , allowing blending and routing strategies that maximise the value of limited downstream capacity.

Complex Design

Material Integrity

Heavy performance

Speed, flexibility

DMS circuits tailored around ore response and cut densities.

Dense Media Separation is treated as a strategic pre-concentration stage that must be matched carefully to ore characteristics and overall plant objectives. In system engineering, testwork, density distributions and liberation data are used to determine whether DMS adds value, which size ranges it should treat, what cut densities are realistic and how products will be routed. Basic engineering then defines the DMS flowsheet: type and location of cyclones or baths, feed preparation steps, by-pass routes, media type, density control strategy and interfaces with crushing, washing, grinding and downstream separation processes. Detail engineering converts this concept into layouts, civil and structural designs, sumps, pump circuits, screen stations, media storage and recovery systems, access platforms and safety provisions. Throughout this progression, cut-density stability, media loss, water balance and ease of operation are treated as primary performance drivers rather than secondary details.

Key engineering tasks and deliverables

Flowsheet development:

  • Selection of size ranges treated by DMS and by-pass fractions
  • Routing of heavy, light and middlings products, including any recombination strategies.
  • Interfaces with crushing, washing, grinding, flotation, magnetic, gravity and tailings handling areas.

Mass and water balance

  • Mass balance across DMS feed, products and recycle streams.
  • Water balance including washing, desliming, media dilution and clarification circuits.
  • Identification of design cases for minimum, normal and maximum throughput.

Duty definition and sizing

  • Feed preparation screens, washing drums and desliming units.
  • Drain and rinse screens for heavy and light product streams.
  • Thickeners, clarifiers and dewatering units associated with DMS and washing
  • Slurry pumps and pipelines in the dense medium, dilution and water circuits.

Layouts and P&IDs

  • DMS modules with screen stations, sumps, pump bays and media tanks.
  • Access platforms, walkways, stairs and safety systems around DMS equipment.
  • Integration of DMS piping and utilities with plant-wide networks.

Commissioning and start-up focus

  • Establishing media density set points and control logic for stable cut density.
  • Verifying media recovery efficiency and wash water performance on all streams.
  • Tuning of flow splits, spray systems and pump duties to achieve design separation.

Key process units in a typical DMS area

  • Crushing and sizing;

    Primary and secondary crushers with screening stages that generate the size fractions suitable for DMS treatment and by-pass streams.

  • Washing and desliming;

    Washing drums, spray screens or other desliming units that remove sticking clays and excessive fines before material enters the dense medium.

  • DMS vessels or cyclones;

    Dense medium baths or cyclones where particles are separated into heavy, light and sometimes middlings streams according to specific gravity.

  • Drain and rinse sections;

    Drain and rinse screens on both heavy and light product streams that recover dense medium and minimise media losses.

  • Media storage, circulation and density control ;

    Tanks, sumps, pumps, densimeters and bleed/trim circuits that maintain stable medium density and cleanliness.

  • Product and waste handling;

    Conveyors, chutes and, where required, dewatering equipment that route heavy products to downstream processing and remove light wastes.

  • Water and fines management ;

    Thickeners, clarifiers and associated pumps that handle process water and fine solids from washing and media recovery circuits.

Complex Design

Material Integrity

Heavy performance

Speed, flexibility

DMS performance maintained as ore and operating conditions evolve.

Services and optimization

Focused audits keep the DMS circuit delivering the expected pre-concentration benefit. Once the plant is in operation, support continues with services that monitor cut density, media stability, product yields and media losses against design values. Process engineers can perform structured surveys of media density control, screen performance and pump operation to identify deviations and improvement options. Mechanical inspections cover screens, pumps, structures and launders for wear, vibration and drainage issues that may compromise separation efficiency. As ore characteristics and operating conditions change, set points, media density targets and flow splits can be adjusted in a controlled way so the economic advantage of DMS is preserved over the life of mine.

Training and long-term partnership

Training programs turn operators into informed pre-concentration specialists. Through dedicated courses and on-the-job coaching, operators, maintenance teams and plant engineers develop a solid understanding of dense media separation principles and the specific behaviour of their own circuit. Training can cover media preparation and density control, screen inspection, pump operation, troubleshooting of instability and coordination between DMS, crushing, grinding and downstream separation. Written operating procedures, checklists and troubleshooting guides then anchor these skills in everyday work. With this combination of engineering, in-house manufactured equipment, slurry pumps and ongoing training, the DMS area becomes a reliable, value-adding part of the concentrator rather than a variable black box.

Complex Design

Material Integrity

Heavy performance

Speed, flexibility