Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Thermal Behavior and Kinetics of Coal Blends during Devolatilization

탈휘발화 과정에서 혼탄의 반응률과 열적 거동에 관한 연구

  • Ryu, Kwang-Il (Energy Conversion System Lab / Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University) ;
  • Kim, Ryang-Gyoon (Energy Conversion System Lab / Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University) ;
  • Li, Dong-Fang (Energy Conversion System Lab / Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University) ;
  • Wu, Ze-Lin (Energy Conversion System Lab / Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University) ;
  • Jeon, Chung-Hwan (Energy Conversion System Lab / Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University)
  • 류광일 (부산대학교 기계공학부 에너지변환시스템연구실/화력발전에너지 분석기술센터) ;
  • 김량균 (부산대학교 기계공학부 에너지변환시스템연구실/화력발전에너지 분석기술센터) ;
  • 이동방 (부산대학교 기계공학부 에너지변환시스템연구실/화력발전에너지 분석기술센터) ;
  • 오택림 (부산대학교 기계공학부 에너지변환시스템연구실/화력발전에너지 분석기술센터) ;
  • 전충환 (부산대학교 기계공학부 에너지변환시스템연구실/화력발전에너지 분석기술센터)
  • Received : 2012.09.20
  • Accepted : 2012.12.03
  • Published : 2013.02.01
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Abstract

The objective of this research is to predict the TG curve of blends of bituminous coal and sub-bituminous coal during devolatilization. TSL (Thermal Shock Large) TGA was used for Experiments, and Coats-redfern method was used for reaction order calculation. Based on reaction order, sum method was verified to be suitable for a single coal, then, prediction and comparison of TG curve of coal blends was conducted using both of WSM (Weight Sum Method) and MWSM (Modified Weight Sum Method), where the latter was developed in this research. The presented experiment results and WSM & MWSM were showed to be reasonable using linear least square method. MWSM performed more accurately than WSM for the case that TG curve had different slopes and the case that sharp weight loss happened due to release of volatile matter. The results showed that it's possible to predict the thermal behavior of coal blends during devolatilization based on the thermal behavior of single coals.

본 연구 목적은 탈휘발화 과정에서의 역청탄과 아역청탄의 혼탄 열중량 곡선을 예측 하는 것이다. TSL (Thermal Shock Large) TGA를 통하여 실험을 수행 하였으며, 반응속도상수 분석은 Coats-redfern 방법을 이용하였다. 도출된 반응속도상수를 기반으로 단일탄의 Sum Method에 대한 일차적 검증을 하였으며, 혼탄시의 TG curve를 WSM(Weight Sum Method)와 저자가 제시한 MWSM (Modified Weight Sum Method)를 사용하여 예측 및 비교하였다. WSM 및 MWSM를 통한 예측결과와 TG curve 실험결과의 정량적인 비교를 위해 Linear least square method를 사용하였다. TG curve 상에서 서로 다른 기울기를 가지는 경우와 많은 휘발분의 방출로 인한 급격한 질량감소가 나타나는 구간의 경우 MWSM이 WSM 보다 실험결과에 더 정확한 결과를 예측함을 확인하였다. 탈휘발 과정에서의 혼탄의 열적 거동은 단일탄의 특성에서부터 예측할 수 있음을 확인할 수 있었다.

Keywords

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