Agustin M. Fudolig*1, Juancho Pablo S. Calvez2, Bernardo V. Bitanga2
Rey V. Perucho2and Carla Joyce C. Nocheseda1
1Metals Industry Research and Development Center, Bicutan, Taguig City, Philippines 1631
2Mines and Geosciences Bureau, Diliman, Quezon City, Philippines 1100
Magnetite sand mined off-shore in the Philippines are sold abroad wherein the value adding involved only beneficiation to achieve marketable grades. This study examines the behavior of beneficiated off-shore magnetite sand during pelletization, induration and reduction tests simulating the Midrex and Corex processes as a means of further value adding. Magnetite sand concentrate at 58.70%Fe and d80 = 54 µm was pelletized into two (2) mixes;20 kg magnetite sand concentrate: 200g bentonite (MIX 1) and the other at 20 kg magnetite sand concentrate: 600 g hydrated lime (MIX 2).
Results obtained for drop numbers and dry compressive strengths of the green pellets for both mixes are low caused by the relatively coarse magnetite sand concentrate. Pot Grate testing were conducted to both MIX 1 and MIX 2 pellets resulting to compressive strengths of 67 and 58 kg/pellet, respectively, which are very low as compared to current industry standards of 250 kg/pellet. MIX 1pellets underwent reduction tests conforming to ISO 11258 while MIX 2 was reduced in accordance with ISO 7215. Reduction degree of 93.7% after 90 minute was achieved simulating the Midrex process which indicates response to this process is slower than industry practice while a reduction degree of 90.61% after 180 minutes simulating the blast furnace or Corex process is about the same as industry standards. However, the reduction-disintegration indices for both mixes did not achieve blast furnace or Corex operation requirements.
Any further information on the results of this study can be inquired from the Mineral Processing Research and Development Section-Metallurgical Technology Division, MGB through telephone number 02-86676700 local 161.