Carolina Vargas and Peter Simons, TOMRA Mining, Germany, explain how methodical testing can show phosphate producers how much silica can be removed from their feed materials to improve yields and lower production costs.
GRABBING GAINS hen producing phosphates for fertilizers, one of the greatest challenges is to reduce the silica content of the mined materials. Though there are several technical solutions, the most efficient and environmentally friendly is sensor-based sorting. Today’s X-ray transmission (XRT) sorting technology is capable of removing 95% or more of
unwanted high-siliceous particles, such as chert and flintstone, from feed materials. This benefits the downstream process by reducing the need for water and chemicals and decreasing maintenance costs. In addition, phosphate recovery rates with single-step sorting are more than 92%, and with double-step sorting recovery rates as high as 99% are reachable. 15
