Upgrading of carbonaceous phosphate rocks by direct carbonation with CO2-water solutions

Department of Chemical Engineering, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
Chemical Engineering and Processing (Impact Factor: 2.07). 08/2004; 43(8):1085-1094. DOI: 10.1016/j.cep.2003.11.001


This work is an investigation of a relatively new process to upgrade carbonaceous phosphate rocks via direct carbonation with CO2–water solution. The process is mainly based on the reaction of the CaCO3 present in the phosphate ore with CO2–water solutions to convert the former to a water-soluble compound (i.e. calcium bicarbonate). The carbonation experiments were carried out in a 0.054 m inner diameter column and 1.7 m high. The parameters that may affect the dissolution of CaCO3 in the CO2–water solution such as column pressure and temperature, CO2-bubbler perforation diameter, CO2 flow rate, phosphate particles size, solid/liquid ratio in the slurry mixture, and the slurry height in the column were investigated. The effects of before-carbonation phosphate ore preheating as well as multiple carbonations were also examined.

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