Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Evaluating the Properties and Commercializing Potential Of Rape Stalk-based Pellets Produced with a Pilot-scaled Flat-die Pellet Mill

파일럿 규모의 평다이 성형기로 제조한 유채대 펠릿의 연료적 특성 및 상용화 가능성 평가

  • Sei Chang Oh (Department of Forest Resources Science, Daegu University) ;
  • In Yang (Institutes of Green Bio Science & Technology, Seoul National University)
  • 오세창 (대구대학교 산림자원학과) ;
  • 양인 (서울대학교 그린바이오과학기술연구원)
  • Received : 2023.09.29
  • Accepted : 2024.01.17
  • Published : 2024.02.01
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Abstract

This study was conducted to evaluate the potential of rape stalk (RAS) as a raw material for the production of solid bio-fuels. RAS was immersed in an aqueous solution with acetic acid concentration of 1 percent, The content of reducing sugars separated from the RAS was analyzed. Glucose showed the highest content followed by xylose, galactose, arabinose and mannose. The immersed and non-immersed RAS were used for producing pellets with a pilot-scaled flat-die pellet mill. Bulk density and calorific values of the pellets improved with the use of the immersed RAS and the addition of wood particles. The values exceeded the minimum requirements for the A-grade of non-woody pellets (≧600 kg/m3 & ≧ 14.5 MJ/kg) designated by the ISO. Ash content of the pellets reduced with the immersion of RAS and the value satisfied the A-grade level (≦6.0%) of the ISO standard. The durability of the immersed RAS-based pellets was much higher than that of non-immersed IRS-based pellets, and the values were increased with the addition of wood particles. However, the durability did not meet the acceptance level for the B-grade of non-woody pellets (≧96.0%) designated by the ISO. These results suggested that the addition of binders in the production of non-woody pellets using an RAS immersed in acetic acid-based aqueous solution is required for the commercialization of the pellets.

본 연구는 고체 바이오연료 생산용 원료로서 유채대의 상용화 가능성을 평가하기 위하여 수행하였다. 대형 플라스틱통에 넣은 유채대를 1% 농도의 초산 수용액에 침지하여 단리된 환원당의 함량을 분석한 결과, glucose의 함량이 가장 높았으며, 다음으로 xylose, galactose, arabinose, mannose 순으로 조사되었다. 파일럿 규모의 평다이 펠릿성형기를 이용하여 무침지 및 침지 유채대로 연료용 펠릿으로 제조하였다. 펠릿의 겉보기밀도와 발열량은 침지처리 및 목분의 혼합과 함께 증가하였으며, 이 측정치는 International Organization for Standardization(ISO)의 비목재펠릿 A 등급 기준을 크게 상회하였다. 회분 함량도 침지처리와 함께 감소하여 ISO의 A등급 기준을 만족하였다. 펠릿 내구성의 경우, 유채대의 침지처리로 증가하였으며, 펠릿 제조에 목분의 첨가와 함께 향상되었다. 그러나 그 측정치는 ISO의 B등급 기준(≧96.0%)에 미치지 못하였다. 따라서 초산 수용액 침지 유채대로 생산할 비목재 펠릿의 상용화를 위하여 내구성 향상을 위한 바인더의 사용이 필요하다는 결론을 얻었다.

Keywords

Acknowledgement

본 논문은 2019년도 대구대학교 학술연구비 지원에 의하여 수행하였다. 한편 유리당 분석에 도움을 준 서울대학교 산림과학부 환경재료과학전공 대학원생들과 유채대 수거를 위하여 긴 시간 수고한 대구대학교 산림자원학과 학생들에게도 감사드립니다.

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