Drain technology for excavated material reduces water consumption

Paste thickeners are contributing to the retrieval of water in the mines of an Indian steel producer and extending the life expectancy of the dam in the slush pit.

Installing a paste thickener to treat sludge generated from iron ore (iron ore tailings, IOT) in the mines of an Indian steel producer has led to a significant decrease in water consumption, which benefits the environment in a country already poor in water, reports Leipzig-based industrial plant engineer Takraf. The paste thickener with a diameter of 15 m was ordered to improve water retrieval in the process plant and to extend the life span of the existing slush pit dam by decreasing the amount of mud that is pumped towards it.
Before, the mine used a common thickener and was pumping an outflow containing 20 to 25% (w/w) solids directly into the slush pit, which caused a high loss of water. With the installation of the paste thickener, the amount of solids in the outflow rose to 50-55% (w/w), which increased the retrieval rate for process water in the plant to 78-83%.
According to Takraf, this then leads to a significant decrease of the amount of fresh water needed in the plant. The drying time for the paste deposited in the slush pit was also significantly decreased, which in turn extended the lifespan of the slush pit.
Source: Takraf