Journal of Energy Engineering (에너지공학)

The Korean Society for Energy (한국에너지학회)
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The Formation Characteristics of Tar, Ash and Clinker due to Combustion of Wood Pellet and Performance Analysis of Wood Pellet Boiler in terms of the Moisture Contents Change of the Wood Pellet

목재펠릿 연소 시 발생하는 타르, 재, 클링커 생성 특성 분석 및 함수율 변화에 따른 목재펠릿보일러의 성능 연구

  • Euh, Seung Hee (Department of Biosystems Engineering, Kangwon National University) ;
  • Oh, Kwang Cheol (Department of Biosystems Engineering, Kangwon National University) ;
  • Oh, Jae Heun (Forest Practice Research Center, Korea Forest Research Institute) ;
  • Kim, Dae Hyun (Department of Biosystems Engineering, Kangwon National University)
  • 어승희 (강원대학교 바이오시스템공학과) ;
  • 오광철 (강원대학교 바이오시스템공학과) ;
  • 오재헌 (국립산림과학원 산림생산기술연구소) ;
  • 김대현 (강원대학교 바이오시스템공학과)
  • Received : 2014.03.11
  • Accepted : 2014.09.05
  • Published : 2014.09.30
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Abstract

This study reports the formation characteristics of tar, ash and clinker due to a wood pellet grade and the performance analysis of wood pellet boiler in terms of the moisture contents change of the wood pellet. Tar was accumulated on the heating surface according to combustion of wood pellet, the ash was yielded on the floor of combustion chamber in a wood pellet boiler and the clinker was solidified at the burner due to combustion of the 3rd grade wood pellet. Especially, the moisture contents is important factor to define the grade. Wood of logging residues has a non-uniform moisture contents after the field process, yields of tar, ash and clinker are increased in case of combustion due to the high ash contents. For these reasons, emission of harmful compounds in the exhaust gas, decrease of boiler efficiency and the system operating errors are observed. In the performance analysis of wood pellet boiler in terms of the moisture contents change of the 1st grade wood pellet, the boiler efficiency was reduced by 27.08% with 6.6% moisture contents increase. The optimum moisture contents of wood pellet is needed to improve the boiler performance and efficiency.

본 연구에서는 목재펠릿의 연소 시 발생되는 타르, 재, 클링커의 생성 특성 분석과 더불어, 1등급 목재펠릿의 함수율에 따른 목재펠릿보일러의 성능 분석이 수행되었다. 타르는 목재펠릿이 연소됨에 따라 생성되어 연소실 전열면에 부착되었고, 전열면에 부착되거나 배기가스와 함께 배출되지 못한 재의 경우, 바닥면에 축적되었으며, 클링커는 3등급 목재펠릿의 연소 중에 버너부에서 생성, 고형화되는 것으로 나타났다. 목재펠릿의 등급이 결정되는 요인으로써 함수율은 중요한 요인으로 작용된다. 벌채부산물을 이용한 목재펠릿은 불균일한 함수율로 인해, 연소 생성물의 발생량이 증가되는 경향을 나타내었으며, 이에 따른 연소시스템에서의 효율 저하, 시스템 작동 오류 등의 문제점이 발생되었다. 특히, 목재펠릿의 함수율에 따른 목재펠릿보일러의 성능 분석에서, 1등급 목재펠릿의 함수율이 6.6%p 증가하였을 때, 보일러효율이 약 27.08%p 감소되는 것으로 나타났다.

Keywords

Acknowledgement

Supported by : 국립산림과학원, 강원대학교

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