Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Study of Drying Characteristics of Low Rank Coal in a Pressurized Micro-riser

가압 마이크로 수송관을 이용한 저급탄의 건조 특성 연구

  • Gwak, In Seop (Department of Resources and Energy Engineering, Chonbuk National University) ;
  • Gwak, You Ra (Department of Resources and Energy Engineering, Chonbuk National University) ;
  • Kim, Ye Bin (Department of Resources and Energy Engineering, Chonbuk National University) ;
  • Lee, See Hoon (Department of Resources and Energy Engineering, Chonbuk National University)
  • 곽인섭 (전북대학교 자원.에너지공학과) ;
  • 곽유라 (전북대학교 자원.에너지공학과) ;
  • 김예빈 (전북대학교 자원.에너지공학과) ;
  • 이시훈 (전북대학교 자원.에너지공학과)
  • Received : 2017.03.02
  • Accepted : 2017.04.05
  • Published : 2017.06.10
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Abstract

With the continuous increase of energy demand, low-grade coal is regarded as one of new energy sources. However, due to the high water content, the utilization efficiency of low-grade coal is not good to be used in recent conversion plants. Therefore, it requires a drying process to lower the water content in low-grade coals. Although a variety of drying experiments were conducted, drying characteristics in accordance with the pressure change has not been progressed. In this study, the flash drying characteristics of low grade coal with high moisture content (21.5 wt%) were determined in a pressurized micro-riser. The effect of operation conditions such as pressure (1-40 bar), dryer temperature ($200-600^{\circ}C$), and tube length (2-6 m) on drying ratios were investigated.

지속적인 에너지 수요의 증가로 인하여 저등급 석탄이 새로운 에너지 자원으로서 인정받고 있다. 그러나 저등급 석탄의 높은 수분 함량으로 인하여 저등급 석탄의 이용 효율은 기존의 석탄 이용 플랜트들에서 이용하기에 부족하다. 따라서 저등급 석탄의 수분 함량을 낮추는 건조 공정이 요구되고 있다. 비록 다양한 건조 실험들이 진행되었으나, 고압조건에서의 건조 특성은 크게 연구되지 않았다. 이에 본 연구에서는 높은 수분 함량을 지닌 저등급 석탄(수분 함량: 21.5 wt%)의 급속 건조 특성을 가압 마이크로 상승관을 이용하여 고찰하였다. 압력(1-40 bar), 건조 온도($200-600^{\circ}C$), 마이크로 상승관 길이(2-6 m) 등의 운전 조건 변화에 따른 저등급 석탄의 건조 특성을 분석하였다.

Keywords

References

  1. J. W. Kook, J. H. Shin, I. S. Gwak, and S. H. Lee, A reaction kinetic study of $CO_2$ gasification of petroleum coke, biomass, and mixture, Appl. Chem. Eng., 26, 184-192 (2015). https://doi.org/10.14478/ace.2015.1006
  2. S. D. Kim, K. S. Lim, and S. H. Lee, Hybrid flash dryer of low rank coal, J. Korean Soc. Combust., 6, 383-387 (2010).
  3. S. H. Lee, S. J. Yoon, H. W. Ra, Y. I. Son, J. C. Hong, and J. G. Lee, Gasification characteristics of coke and mixture with coal in an entrained-flow gasifier, Energy, 35, 3239-3244 (2010). https://doi.org/10.1016/j.energy.2010.04.007
  4. S. H. Lee, S. T. Park, R. S. Lee, J. H. Hwang, and J. M. Sohn, Water gas shift reaction in a catalytic bubbling fluidized bed reactor. Korean J. Chem. Eng., 33(12), 3523-3528 (2016). https://doi.org/10.1007/s11814-016-0208-1
  5. S. V. Jangam, M. Karthikeyan, and A. S. Mujumdar, A critical assessment of industrial coal drying technologies: Role of energy, emissions, risk and sustainability, Drying Technol., 29, 395-407 (2011). https://doi.org/10.1080/07373937.2010.498070
  6. M. Karthikeyan, W. Zhonghua, and A. S. Mujumdar, Low-rank coal drying technologies current status and new developments, Drying Technol., 27, 403-415 (2009). https://doi.org/10.1080/07373930802683005
  7. D. J. Allardice, A. L. Chaffee, W. R. Jackson, and M. Marshall, Water in brown coal and dewatering. In: C.-Z. Li (ed.), Advances in the Science of Victorian Brown Coal, 85-133, Elsevier (2004).
  8. H. Osman, S. V. Jangam, J. D. Lease, and A. S. Mujumdar, Drying of low-rank coal (LRC)-A review of recent patents and innovations, Drying Technol., 29(15), 1763-1783 (2011). https://doi.org/10.1080/07373937.2011.616443
  9. J. R. Gao, X. X. Tao, T. Hou, and Y. Z. Wan, Progress of lignite drying and dehydration technology, Clean Coal Technol., 14(6), 73-76 (2008).
  10. B. Jiang, S. Li, J. R. Gao, G. L. Liang, H. Meng, and Z. G. Yang, Development and application situation of lignite drying technology, Clean Coal Technol., 6, 23-28 (2011).
  11. R. Zhonghao, Z. Yuemin, H. Congliang, D. Chenlong, and H. Jingfeng, Recent developments in drying and dewatering for low rank coals, Prog. Energy Combust. Sci., 46, 1-11 (2015). https://doi.org/10.1016/j.pecs.2014.09.001
  12. C. Bergins, Kinetics and mechanism during mechanical/thermal dewatering of lignite, Fuel, 82(4), 355-364 (2003). https://doi.org/10.1016/S0016-2361(02)00310-1
  13. J. Wu, J. Liu, X. Zhang, Z. Wang, J. Zhou, and K. Cen, Chemical and structural changes in XiMeng lignite and its carbon migration during hydrothermal dewatering, Fuel, 148, 139-144 (2015). https://doi.org/10.1016/j.fuel.2015.01.102
  14. T. G. Eom and S. M. Choi, Performance evaluation of a flash dryer and a rotary kiln dryer for upgrading low rank coal, J. Korean Soc. Combust, 20(2), 1-13 (2015). https://doi.org/10.15231/JKSC.2015.20.2.001
  15. N. Nikolopoulos, I. Violidakis, E. Karampinis, M. Agraniotis, C. Bergins, P. Grammelis, and E. Kakaras, Report on comparison among current industrial scale lignite drying technologies (A critical review of current technologies), Fuel, 155, 86-114 (2015). https://doi.org/10.1016/j.fuel.2015.03.065