华电技术 ›› 2020, Vol. 42 ›› Issue (7): 74-80.

• 气化残炭利用 • 上一篇    下一篇

气化残炭与低阶煤混燃特性及动力学分析

  

  1. 1.太原工业学院 化学与化工系,太原 030008;2.中国科学院山西煤炭化学研究所,太原 030001
  • 出版日期:2020-07-24 发布日期:2020-07-24

Co-combustion characteristics and kinetics analysis of residual carbon from gasification and low-rank coals

  1. 1.Department of Chemistry and Chemical Engineering,Taiyuan Institute of Technology,Taiyuan 030008,China; 2.Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China
  • Online:2020-07-24 Published:2020-07-24

摘要: 低挥发分气化残炭的高效燃烧对其分级利用十分关键,与煤混燃是解决气化残炭着火点高、难燃尽等问题的一种有效途径。利用热重分析法研究了气化残炭与3种低阶煤(云南褐煤、哈密长焰煤、神华不黏煤)的混合燃烧特性,获得了低阶煤与气化残炭混燃时的特征参数以及相互作用,并利用多重扫描速率法对气化残炭和低阶煤混燃过程的动力学参数进行了分析。结果表明,气化残炭与煤混燃时二者最大燃烧峰温差(Δt)较单独燃烧时的温差有所降低,且与神华不黏煤和云南煤混燃时随着气化残炭掺入比例的增加Δt逐渐降低,说明二者混燃时存在明显的相互作用。煤中挥发分的逸出和燃烧会提高气化残炭的燃烧性能,哈密煤中富含的钙铁等矿物对气化残炭的燃烧具有一定的催化作用。动力学分析结果表明,相对于气化残炭,混燃样品的活化能整体上都有所降低,说明气化残炭与煤混燃可以提高整体的燃烧性能。

关键词: 气化残炭, 低阶煤, 混燃, 燃烧特性, 燃烧动力学, 煤气化, 热重分析法

Abstract: High-efficiency combustion of residual carbon from gasification(RCG)is key to its cascade utilization. Cocombusting it with coal is a promising method to lower the fire point and dent the difficulty in burn-out.Studying the cocombustion characteristics of RCG and three low-rank coals(YN lignite,HM long flame coal and SH non-caking coal)by thermogravimetric analysis,their featured parameters and interactions were obtained. Taking multiple scanning method, the co-combustion kinetics parameters of RCG and low-rank coals were analyzed. The results showed that the peak temperatures difference(DT)of co-combusted RCG and coals was narrowed down,compared with that of an individual fuel. And DT decreased with the mounting of RCG when it was co-combusted with SH coal and YN coal,which indicated apparent interactions between RCG and coals during co-combustion. The release and combustion of volatile matters could promote the combustion of RCG.The rich calcium and iron in Hami coal had a certain catalytic effect on the combustion of RCG. According to kinetics analysis,the apparent activation energy of the blended sample is lower compared to that of RCG,which implied the overall combustion performance could be improved by co-combustion of RCG and coals.

Key words: residual carbon from gasification, low-rank coals, co-combustion, combustion characteristics, combustion kinetics, coal gasification, thermogravimetric analysis