THE STUDY OF REDUCTION PROCESS OF MANGANESE ORE AND COPPER SLAG MIXTURE WITH COAL TO PRODUCE FERROSILICOMANGANESE ALLOY

• Main Author: Muhammad Fauzian, Irfan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/39189
• Institution: Institut Teknologi Bandung

The production of crude steel in the world is increasing with total global production around 1,689 billion ton in 2017 and it is predicted to further increase based on the statistic data from World Steel Association. Indonesia is the 23rd rank producer of crude steel with estimated national production around 5,5 million ton. Unfortunately, that amount of production has not been achieved at the required amount needed to fulfill the national demand. Therefore, Indonesia needs to increase the production of raw material needed to maximize the production of crude steel economically. One of the efforts to fulfill that duty is by maximizing the production of manganese ferroalloys that is commonly used as one of the alloying material to produce crude steel. The manganese ferroalloy production will need iron ore and quartz with large quantities. Therefore, there is an alternative idea to make the production more economically, which is to use by product of other metal production that contains large amount of iron and silicon. One of the by product that fits the criteria is copper slag that contains a large amount of FeO and SiO2. Because of that reason, this research focuses on the possibility of the use of manganese ore and copper slag as an alternative raw material to produce FeSiMn. Series of experiments have been conducted to investigate the effects of temperature variation and the addition of copper slag in the reduction of manganese ore to the composition of Fe, Si, and Mn in the metal. Manganese ore, variation of copper slag of 20%, 40%, 60%, 80% and 100% addition with the basis of manganese ore, and coal were mixed and agglomerated to make briquettes and then were reduced inside a muffle furnace for 205 minutes using an isothermal-gradien temperatur with the initial isothermal temperature of 1000°C and the final isothermal temperature varies at 1450°C, 1500°C, and 1550°C. The sample of metal and slag was prepared and observed using an optical microscope and SEM-EDS to see the composition of Fe, Si, and Mn in the metal. The results of the research shows that in the range of 1450°C-1550°C, increasing final isothermal temperature will increase the metal recovery and the content of Mn and Si, meanwhile the content of Fe is decreased. The content of Fe in 1450°C, 1500°C, 1550°C consecutively are 80.27%, 65.73%, and 66.01%. The content of Si consecutively are 1.77%, 12.66%, and 13.12%. The content of Mn consecutively are 12.89%, 19.32%, and 20.54%. The effect of the addition of copper slag is also observed, the result shows the addition of copper slag will increase the metal produced and the content of Fe in the metal and decrease the content of Mn and Si. The content of Fe in the variation addition of copper slag 20%, 60%, and 100% consecutively are 53.36%, 65.73%, and 75.24%. The content of Si consecutively are 12.53%, 11.02%, and 8.13%. The content of Mn consecutively are 34.39%, 19.32%, and 14.54%.