Perpustakaan Digital ITB

The ferronickel industry in Indonesia, primarily utilizing the Rotary Kiln Electric Furnace (RKEF) process, heavily relies on coal, resulting in significant greenhouse gas emissions. This study evaluates the feasibility of decarbonizing the RKEF process by substituting coal with biomass gasification. Using Aspen Plus process simulation, this research analyzes the effects of biomass moisture content (6.6% to 40%) and gasifying agents (steam-oxygen and air) on syngas composition, overall thermal efficiency, carbon emissions, and techno-economic viability. The results indicate that increasing biomass moisture content degrades syngas quality and reduces the thermal efficiency of the RKEF process from a 43% coal baseline to 31.8%- 35% for steam-oxygen and 28.2%-32.5% for air gasification. Despite this efficiency penalty, biomass substitution yields substantial environmental benefits, reducing CO2 emission intensity by 40.4% to 54.5% compared to the coal baseline (0.1984 tons CO2/ton calcine). From a techno-economic perspective, replacing coal with biomass gasification imposes an additional financial burden. The steam-oxygen configuration incurs a higher incremental cost of $19.19–$22.24/ton calcine due to the capital-intensive Air Separation Unit (ASU), translating to a Levelized Cost of CO2 Avoidance (LCOA) between $177.63 and $269.22 per ton of CO2 avoided. Conversely, air gasification offers a lower incremental cost of $9.70–$10.89/ton calcine and a highly competitive LCOA between $91.33 and $136.03 per ton of CO2 avoided. Therefore, while both methods significantly decarbonize the process, air gasification emerges as the more economically viable pathway