SELECTION OF METHODS FOR SEPARATION OF MINERALS OF MARINE PLACERS

Modern life is unthinkable without the trendy gadgets, clean engines, high-quality sound systems and many other high-tech products.

Development of marine placers are very promising direction.

PLACER DEPOSITS ARE RAW MATERIAL FOR RARE EARTH ELEMENTS, TITANIUM, TANTALUM, NIOBIUM, ZIRCONIUM, TIN AND OTHER METALS

In the world, there are more than 173 fields of REE marine placers. However each placer deposit has its own individual characteristics. Each ore must have its own individual technology

For example, approximately half of the alluvial deposits is located in Eastern A.

Typically, the composition of sand is very simple and consists of five minerals: monazite, ilmenite, rutile, zircon, quarz. Placer deposits contain 0.8-15% of heavy minerals. Monazite content in the ore is low and there is in a range of 0.002-0.2%. In the majority of the alluvial deposits, content of monazite is 0.03-0.06%.

Processing technologies for sands of deposits can be simple of the same type. These may include:

• • Gravity separation

  • Magnetic separation

  • Electrical separation

The resulting concentrates:

• • REE concentrate (monazite)

  • Titanium concentrate (ilmenite, rutile)

  • Zirconium concentrat (zircon)

Approximately half of the alluvial deposits is located in Western A. These deposits have a more complex composition.

Placers are the complex raw materials and they contain:

• • REE mineral (monazite)

  • Titanium minerals (ilmenite, rutile and sometimes leucoxene)

  • Zirconium minerals (zircon)

  • Tin minerals (cassiterite)

  • Corundum

  • Garnet

  • Kyanite

  • Quarz (ganga)

Processing techniques may be more complex. Since the content of monazite in sands is very low, these sands the can be processed profitably only with reception of all possible concentrates: Monazite, Titanium, Zirconium, Tin, Corundum, Garnet, Kyanite.

Processing technologies for sands of deposits may include:

• • Gravity separation

  • Magnetic separation

  • Electrical separation

  • Flotation

The processing of placer deposits has many advantages:

1. Processing of placer deposits is produced by environmentally friendly technology without the use of any chemicals. Virtually no negative impacts on the flora and fauna of the ocean and coastal areas.

2. Processing of placer deposits decreases the radiation background at the shores of seas and oceans. The ecological situation is improving becourse radioactive minerals are removed from the beaches. Beaches become a beautiful light color.

3. Good working conditions without dust and chemical vapours.

4. Perhaps the complex use of raw materials and the obtaining of several concentrates, which increases profit.

5. The use of cheap technology.

6. Low cost of search and exploration of placer deposits. One deposit can be used for long time. Ocean continuously feeds new portions of raw materials without a limit.

7. There are no the costs for the construction of the quarry or mine.

8. Low construction costs for the processing plant. One floating plant – the marine dredge can be used for 50 years and more at the numerous placer deposits.

9. There are no the costs of crushing and grinding.10. There are no the waste rock dumps, tailings containing hazardous and radioactive waste. There are no the costs for it.

11. There are no the costs of restoring the site.

12. Fresh water is not used. There are no the costs of preparation and purification of fresh water. Separation is made directly in seawater. Not any chemicals or minerals pollute the seawater.

© Ph.D. Natalia Petrovskaya, 10.12.2017