Beneficiation of Saudi phosphate ores part II : the application of column flotation

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.

Phosphoric acid industry is expected to develop in Saudi Arabia in the near future. This is ascribed to the discovery of phosphate ores in the northern part of the kingdom, the availability of sulphur, "required for this industry", as a byproduct from petrochemical industries in the kingdom and the construction of phosphate fertilizers required by the growing agricultural sector in Saudi Arabia. The discovered Saudi phosphate ores are of sedimentary origin with carbonaceous impurities as calcite and dolomite. The beneficiation of this type of ores is a key factor for successful production of phosphoric acid by the wet process. Froth flotation is one of the promising techniques acquiring large potential in the separation of calcite from such phosphate ores. In our previous work "Part I" of this project, an extensive experimental study using a conventional flotation cell for phosphate beneficiation was carried out and the optimum flotation parameters were achieved. During the next phase of our project "Part II", column flotation has been recognized in literature as one of the most significant advances in froth flotation technology in the last decade. These units, in a single separation step, can achieve a product recovery and purity equivalent to or even better than that obtained by multistage flotation in conventional flotation cells. Hence, in the present work, a flotation column of 1.5 m height and 6.5 cm diameter has been designed and applied in the beneficiation of Al-Jalamid Saudi Phosphate ores of the calcareous type. The significant parameters like air flow rate, slurry feed rate, particle size of processed ore, wash water consumption and collector doses of flotation process are investigated in the present work to achieve the best recovery and quality of the beneficiated ores. Moreover, the optimum flotation parameters previously obtained in the single flotation cell were also applied in the present column flotation runs.