Separation of Iron Oxide from Harbor Waste Using Selective Flocculation

Constanta port operations involving the handling of bulk minerals often lead to material losses, resulting in mineral waste, containing a mixture of iron ore, bauxite, and coal, amongst others. In order to recover these minerals, a processing plant was built, which successfully separates most of this waste into its constituents. However, a byproduct obtained from this process is a sludge containing fine particles below 0.5 mm, which are deposited in a reservoir that represents definitive tailings. Since this is a “rich” tailing material, which is difficult to be extracted by using conventional methods due to its small size, the selective flocculation procedure was tested as an alternative method. This paper presents the results obtained for standard methods of selective flocculation tests using polyacrylamide A 100 at a pH value of 10.5. SEM-EDS and XRD analyses were performed, and the chemical composition of the sample components was given. According to preliminary tests, using the selective flocculation procedure, the expected results were obtained in terms of separating the overflow between the content of impurities (with a reduced share of Fe in relation to the input) and sediment with an increased content of Fe (with a reduced share of impurities in relation to the entrance).