Partial metallisation of manganese before smelting is challenging but other forms of thermal treatment offer a viable opportunity to reduce the electrical power consumption and increase the productivity of manganese smelters. Manganese ore pre-treatment include the following: pre-heating in a shaft furnace or rotary kiln with
furnace off-gas; calcinations in a shaft furnace or rotary kiln; nodulizing; sintering ore fines or pellets in a shaft furnace, travelling grate (linear or carousel configurations), grate-kiln or steel belt sinter plant. These technologies are well-known, but with the exception of travelling grate sintering not commonly used. All these pre-treatment technologies reduce operating cost by a varying degree. At the same time, single unit capacities and capital costs for the options are significantly different. The proposed article addresses the application of the different technologies to different ore types (oxide ore, carbonate ore and pyrolusite ore), technical advantages of each manganese ore pre-treatment technology and the impact of each technology on operating- and capital cost. Operating availability, number of operating units and risks associated with each technology are also discussed in the article.
Keywords: manganese ore, sintering, pelletizing, calcination