Abstract:

Biomass resources are abundant and cheap, which has attracted the attention of researchers due to its advantages such as clean, renewable and carbon neutral. However, its shortcomings such as low energy density, high moisture and oxygen content also limit its large-scale application; in addition, when biomass is directly gasified, the synthesis gas has a low calorific value and a large amount of tar is produced. This article describes the effect of torrefaction on the improvement of biomass fuel quality and the positive regulation of the gasification process. After the biomass is torrefied, the oxygen content, H/C and O/C decrease while the fixed carbon content and high heating value increase. The grindability and hydrophobicity are also improved to a certain extent, which makes up for the torrefaction to a certain extent in terms of energy consumption. The improvement of biomass fuel quality is explained microscopically, and the characteristics and advantages of microwave torrefaction are briefly described. Using torrefied biomass for gasification, the synthesis gas has high combustible components, and the tar output decreases. The follow-up work can be considered from the following three aspects: the whole life cycle assessment of the "torrefaction-utilization" process, the use of microwave technology to more accurately explore the influence mechanism of temperature on the torrefaction effect, and the combination of torrefying and tar catalytic reforming technology to further reduce tar production.

Key words: biomass, torrefaction, gasification, hydrogen, tar

摘要：

生物质资源丰富廉价，因清洁可再生、碳中和等优点备受研究者的关注，但是其能量密度低、水分和氧含量高等缺点也限制了其规模化应用；另外，生物质直接气化产生的合成气热值较低，且会产生大量焦油。本文阐述了烘焙预处理对生物质燃料品质的提升以及对气化过程积极的调控作用。文章指出，生物质烘焙后，氧元素含量、H/C和O/C下降，固定碳含量和高位热值增加；可磨性和疏水性得以提高，在一定程度上弥补了烘焙过程的耗能。文中从微观角度对生物质燃料品质的提升进行了解释，并简述了微波烘焙的特点与优势。使用烘焙生物质气化，产生的合成气可燃成分高，且焦油产量有所下降。文章总结后续工作可以考虑从以下三个方面展开，即对“烘焙-利用”过程进行全生命周期评价、利用微波技术更准确地探索温度对烘焙效果的的影响机制、结合烘焙与焦油催化重整技术进一步降低焦油产量。

关键词: 生物质, 烘焙, 气化, 氢, 焦油