Indonesia aims to achieve Net Zero Emissions (NZE) by 2060 through the decarbonization of its energy sector. As a transitional solution, Carbon Capture, Utilization, and Storage (CCUS) technology, specifically oxy-fuel combustion, offers a viable pathway to balance emission reductions with energy security. This study evaluates the implementation of oxy-fuel combustion (O2/RFG) in a 60 MWe CFB boiler at the Pulang Pisau Thermal Power Plant using Ansys Fluent 2025 R1 by replacing N₂ with dry CO₂. By maintaining constant coal feeding and oxygen supply rates, the results demonstrate increases in bed temperature (7.45%) and cyclone outlet temperature (8.37%). These enhanced thermal characteristics drive a sharp surge in CO₂ concentration by 325.12%, while simultaneously reducing SO₂ and NO_x emissions by 43.0% and 13.88%, respectively. This research confirms the technical feasibility of retrofitting existing CFB units with oxy-fuel technology, providing valuable insights into how oxygen enrichment influences thermal performance and emission profiles during the transition toward cleaner energy production.

Carbon capture; CFB boiler; Emission reduction; Numerical simulation; Oxy-fuel combustion

Bryden, K. M., Ragland, K. W., & Kong, S.-C. (2022). Combustion engineering (3rd ed.). CRC Press. DOI : 10.1201/b22232

Chang, J., Ma, X., Wang, X., Li, X. (2023). CPFD modeling of hydrodynamics, combustion and NOx emissions in an industrial CFB boiler. Particuology 81. pp 174-188. https://doi.org/10.1016/j.partic.2022.12.019

Chen, G., Li, S., & Wang, L. (2023). Current investigation status of oxy-fuel circulating fluidized bed combustion. Fuel 342. https://doi.org/10.1016/j.fuel.2023.127699

Cheng, L., Li, K., Yu, Q., & Zhang, Q. (2025). The application of numerical methods in the design of large-size CFB boilers. Applied Thermal Engineering 280, Article 128243. https://doi.org/10.1016/j.applthermaleng.2025.128243

Dong, L., Wang, L., Wen, H., Lin, Z., Yao, Z., Zou, C., Xu, H., Hu, H., Yao, H. (2024) Numerical investigation of the oxy-fuel combustion in the fluidized bed using macroscopic model supported by CFD-DDPM. Journal of Environmental Chemical Engineering 12. https://doi.org/10.1016/j.jece.2024.113959

Indrawan, M, D. (2022). Studi Numerik Karakteristik Aliran dan Pembakaran Furnace PLTU Muara Karang dengan Variasi Kadar O2 pada Udara Pembakaran. Thesis. Institut Teknologi Sepuluh Nopember.

Kiga, T., Takano, S., Kimura, N., Omata, K., Okawa, M., Mori, T., & Kato, M. (1997). Characteristics of pulverized-coal combustion in the system of oxygen/recycled flue gas combustion. Energy Conversion and Management, 38(Suppl.), S129–S134. https://doi.org/10.1016/S0196-8904(96)00258-0

Krzywanski, J., Sztekler, K., Szubel, M., Siwek, T., Nowak, W., Mika, L. (2020). A Comprehensive, Three-Dimensional Analysis of a Large-Scale, Multi-Fuel, CFB Boiler Burning Coal and Syngas. Part 1. Numerical Simulations of Coal and Syngas Co-Combustion. https://doi.org/10.3390/e22090964

Krzywanski, J., Sztekler, K., Szubel, M., Siwek, T., Nowak, W., Mika, L. (2020). A Comprehensive, Three-Dimensional Analysis of a Large-Scale, Multi-Fuel, CFB Boiler Burning Coal and Syngas. Part 2. Numerical Simulations of Coal and Syngas Co-Combustion. https://doi.org/10.3390/e22080856