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The Korean Hydrogen and New Energy Society (한국수소및신에너지학회)
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Pyrolysis Behavior of Pulverized Coal Particles at High Heating Rate

미분탄 입자의 고속가열 열분해거동 해석

  • Received : 2019.05.23
  • Accepted : 2019.06.30
  • Published : 2019.06.30
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Abstract

The pyrolysis characteristics of pulverized coal particle was numerically analyzed with the drop tube furnace. Based on the simulated gas flow field in the drop tube furnace, the particle velocity, temperature and volatile evolution were calculated with the fourth order Runge-Kutta method. The effects of changes in reactor wall temperature and particle diameter on the pyrolysis behavior of coal particle were investigated. The particle heating rate was very sensitive to the reactor wall temperature and particle size, that is, the higher wall temperature and the smaller particle size resulted in the higher heating rate and the consequent quicker volatile evolution.

Keywords

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Fig. 1. Schematic diagram of the present DTF system

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Fig. 2. Axial gas velocity in the DTF reaction tube depending on the inlet condition

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Fig. 3. Axial gas temperature in the DTF reaction tube depend-ing on the wall temperature

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Fig. 4. Axial particle velocity in the DTF reaction tube at Tw=1,273 K depending on the particle diameter

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Fig. 6. Particle residence time in the DTF reaction tube at Tw=1,273 K depending on the particle diameter

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Fig. 7. Particle residence time in the DTF reaction tube at Tw=1,473 K depending on the particle diameter

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Fig. 10. Volatile release of 70 μm coal particle in the DTF re-action tube at different wall temperatures

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Fig. 11. Volatile release of 100 μm coal particle in the DTF re-action tube at different wall temperatures

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Fig. 5. Axial particle velocity in the DTF reaction tube at Tw=1,473 K depending on the particle diameter

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Fig. 8. Particle and gas temperature in the DTF reaction tube at Tw=1,273 K depending on the particle diameter

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Fig. 9. Particle and gas temperature in the DTF reaction tube at Tw=1,473 K depending on the particle diameter

Table 1. Coal properties for experiment

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