Alternativas de processo para concentração do minério fósforo-uranífero de Itataia

• Ano de defesa: 2010
• Autor(a) principal: Rodrigo Oscar de Albuquerque
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: flotação de fosfato; fosfato sílico-carbonatado; flotação aniônica; Engenharia metalúrgica; Tecnologia mineral; Engenharia de minas; Minérios
• Link de acesso: http://hdl.handle.net/1843/BUOS-8DUKH8

The search for selectivity in flotation systems involving slightly soluble minerals has been the motivation for several investigations. Fundamental studies as well as laboratory and pilot scale tests have been performed with different ore types and reagents systems, aiming at subsidizing such separation. The low selectivity is attributed to the similarity in electrokinetic properties, solubility and surface chemistryof the minerals. The Brazilian silicate-carbonate phosphate ores are an example of this problem. This ore type represents a significant percentage of our reserves and responds poorly to the flotation process and, in many instances, any process route was yet developed. In the present investigation different process alternatives were investigated for the flotation of the phosphate uranium bearing ore from Itataia (CE) searching for the selectivity among apatite, calcite, and silicates. The flotation of each mineral class was individually investigated at laboratory scale and the different process routes were evaluated. The last stage consisted of apatite direct flotation in pilot columns. The results showed that either the apatite flotation route or the calcite flotation followed by apatite flotation route are adequate alternatives for the concentration of the ore under investigation, in addition to the previously investigated route consisting of bulk flotation followed by calcite flotation. The achieved results also confirm the efficiency of citric acid as apatite depressant, replacing phosphoric acid. The composition of coconot oil, a collector used in direct flotation, different from that of other collectors used in phosphate plant practice flotation, is probably responsible for the selectivity between apatite and contaminants, especially calcite. On the other hand, the use of carbon dioxide in calcite flotation followed by apatite flotation rendered possible the utilization of a low soy bran oil dosage in the calcite/apatite separation.