Advances in Energy Research

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Coal pyrolysis behaviors at supercritical CO2 conditions

  • Hakduck Kim (Graduate School of Convergence for Clean Energy Integrated Power Generation, Pusan National University) ;
  • Jeongmin Choi (School of Mechanical Engineering, Pusan National University) ;
  • Heechang Lim (School of Mechanical Engineering, Pusan National University) ;
  • Juhun Song (School of Mechanical Engineering, Pusan National University)
  • Received : 2021.05.15
  • Accepted : 2022.07.27
  • Published : 2022.12.25
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Abstract

In this study, a product gas yield and carbon conversion were measured during the coal pyrolysis. The pyrolysis process occurred under two different atmospheres such as subcritical (45 bar, 10℃) and supercritical CO2 condition (80 bar, 35℃). Under the same pressure (80 bar), the atmosphere temperature increased from 35℃ to 45℃ to further examine temperature effect on the pyrolysis at supercritical CO2 condition. For all three cases, a power input supplied to heating wire placed below coal bed was controlled to make coal bed temperature constant. The phase change of CO2 atmosphere and subsequent pyrolysis behaviors of coal bed were observed using high-resolution camcorder. The pressure and temperature in the reactor were controlled by a CO2 pump and heater. Then, the coal bed was heated by wire heater to proceed the pyrolysis under supercritical CO2 condition.

Keywords

Acknowledgement

This work was supported by Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government (MOTIE) (20214000000140, Graduate School of Convergence for Clean Energy Integrated Power Generation). The authors also thank for the financial support from the National Research Foundation of Korea (NRF) grant (NRF-2020R1F1A1051343) funded by the Korean Government (MEST).

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