Geochemical Assessment and Mobility of Undesired Elements in the Sludge of the Phosphate Industry of Gafsa-Metlaoui Basin, (Southern Tunisia)

The raw phosphates in the Gafsa-Metlaoui phosphate basin are valorized by wet processes that performed laundries of Gafsa Phosphates Company (CPG, Gafsa, Tunisia) to reach market grades (>28% P2O5). This enrichment process allows increase P2O5 content elimination coarse (>2 mm) and fine (<71 µm) fractions. Mineralogical analysis has shown all investigated materials (raw phosphate, marketable waste, waste) from M’Dhilla-Zone L Redeyef both composed carbonate fluorapatite, carbonates, quartz, gypsum, clays, clinoptilolite. Chemical shows Cr, Cd, Zn, Pb, U concentrated wastes associated with clay–phosphate fraction. rare earth elements more phosphates. Drilling sludge-water analysis, along leaching tests conducted on wastes, showed that, due industry, cadmium, fluorine, sulfate contributing pollution water resources region, is conspicuous at M’Dhilla.