(385d) Effect of Filtration On the Concentration of Aqueous Ions in Process Water and Filter Cake Moisture During Iron Ore Beneficiation

The filtration processes within selective flocculation and dispersion iron ore beneficiation plants cause aqueous ions from the process water to concentrate within the filter cake moisture. These high concentrations of ions can lead to significant operational issues during downstream pelletization and reduction processes. This paper examines the ionic content of concentrated iron ore slurry that is filtered at an operating selective flocculation and dispersion hematite beneficiation plant and relates it to the ionic content of the moisture in the resultant filter cake. Water analyses were conducted to determine the sodium, potassium, calcium, magnesium, fluoride, chloride, nitrate, nitrite, carbonate, sulfate, and phosphate concentrations within the filter feed slurry and filter cake moisture of an operating hematite beneficiation plant. Results have shown that all tested ions within the process are more concentrated within the filter cake moisture than in the filter feed slurry. This has been attributed to the physical and chemical surface interactions of these ions with the iron ore particle surfaces. Of these ions, phosphorus concentrates the most with the filter cake moisture content having a phosphorus content that is 24.67 times that of the filter feed slurry.