采用两种不同的升温制度对生物质进行碳化，碳化温度选为300、400、500、600和700℃，保温时间分别为30、60和90min．利用扫描电镜及热重分析仪对所得生物质焦的成分、微观结构及燃烧性能等进行分析，并研究了制备条件对生物质焦的产率及与CO2反应性的影响．结果表明，生物质焦具有与煤不同的典型管状或片状结构，其N、S、灰分、碱金属含量及燃烧性能优于煤炭，适合用作炼铁过程的还原剂和发热剂，以替代部分煤粉和焦炭．综合考虑，炼铁用生物质焦的最佳制备条件是，采用恒温加热模式将生物质加热至500℃进行碳化，并保温30min．%Raw biomass was carbonized by two different heating patterns to produce biomass char at 400, 500, 600 and 700 ℃ for 30, 60 and 90 min. The composition, microstructure, and combustibility of the derived biomass char were investigated by scanning electron microscopy （SEM） and thermogravimetric analysis （TG-DTG）. The effects of preparing conditions on the biomass cbar＇s yield and reactivity for reacting with CO2 were studied. It is shown that the biomass char has typical duct structure or sheet structure, which is different from coal. The contents of N, S, ash and alkali metals in the biomass char are much lower, but its combustibility is better than coal samples, suitable for using as a reducing agent and a heating agent in ironmaking to partially replace coal and coke. The opti- mum preparing condition of biomass char for ironmaking is to carbonize raw biomass by a constant temperature heating pattern at 500 ℃ for 30 min.
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