One of the most abundant mineral resources in the Philippines are Nickel Laterite Deposits. In fact, the country is one of the top exporters of raw nickel laterite ores in the world. Yet, despite its abundance nickel laterites are understudied. This study aimed to evaluate the processing of low nickel-high iron laterite deposits in the country through laboratory scale production of nickel pig iron / pig iron using an electric arc furnace. The technology employed pyrometallurgical processing to reduce the iron oxides to metallic iron. However, the study encountered several challenges during its implementation. Such challenges include low strength of prepared pellets and low degree of metallization of the pellets.
Based on the results of the drop test, only 70% of the pellets retained on the plus 4 mesh (4.46 mm). The value was considerably lower compared to the standard of 95% weight retained for the shatter index which can be attributed to several factors such as non-optimized mixture of pellets, and effects of induration time and temperature limitation of the furnace from its maximum temperature of 1,100oC against the ideal induration temperature of 1,300oC. During the reduction stage, the pellets were not able to attain at least 80% degree of metallization due to the rotary kiln’s condition near obsolesce. Consequently, the low percent metallization of the products resulted in the failure of smelting process to produce the pig iron product.
Bernardo V. Bitanga and Maria Luisa A. Sajonas
Engineer III, Mineral Processing Research and Development Section
Metallurgical Technology Division, Mines and Geosciences Bureau