Ironing out the problems with iron ore tailings

The iron we use today comes from oceans that existed nearly two billion years ago that were teaming with dissolved iron. When the first organisms capable of photosynthesis began releasing oxygen into these iron-rich bodies of water, iron started forming as deposits on the Earth’s crust, which means it is primarily found in sedimentary rocks.

Ores containing high quantities of magnetite (which contains about 72% iron) and hematite (which contains about 70% iron) are known as “natural” or “direct shipping” ores. These materials can go directly to iron making furnaces for the production of steel. However, since the ore deposits that were sinking to the ocean floor billions of years ago mixed in with other elements and minerals, iron is often found in what’s known as banded iron formations. These generally contain a much lower concentration of iron mixed in with silicates, oxides, and in some cases carbonates. Doing the math, pulling one ton of iron ore from banded formations creates up to three tons of tailings.

While it’s true that iron is the fourth most common element found on our planet’s surface (after oxygen, silicon, and aluminum), tons of it is basically being “thrown away” because it’s not being properly extracted. At the moment, there doesn’t seem to be a shortage of iron in the world. However, mining it does have an environmental impact. And tailings that are generated by wet magnetic and flotation techniques need fresh water sources, require the introduction of expensive and potentially toxic chemicals that must be stored until decontaminated.

ST Equipment & Technology has a better solution. Our triboelectrostatic dry separation process can maximize the removal of iron ore from waste streams, eliminating the need for a fresh-water source, the expense of flotation chemicals, and the construction of wet process tailing ponds. No decontamination is necessary. Our separator is environmentally friendly because it doesn’t use a lot of energy, but it can process a high volume of material quickly to increase your output—not only of iron ore, but any other valuable elements that may be in your tailings including copper, nickel, and cobalt. In addition, the separator can be used at your mining site so there’s not need or expense for shipping materials to a facility for sorting.