锯末水热生物炭特征研究  

FEATURE RESEARCH OF HYDROTHERMAL BIOCHAR FROM SAWDUST

作　　者：邢献军 范方宇 施苏薇 张贤文 马培勇 李永玲 

机构地区：[1]合肥工业大学先进能源技术与装备研究院,合肥230009 [2]国家城市能源计量中心(安徽),合肥230051 [3]合肥工业大学化学与化工学院,合肥230009 [4]西南林业大学林学院,昆明650224

出　　处：《太阳能学报》2018年第2期299-306,共8页Acta Energiae Solaris Sinica

基　　金：国家科技支撑计划(2012BAD30B01)

摘　　要：以锯末（sawdust，SD）生物质为原料，采用水热炭化法在温度170、200、230℃，时间15、30min下制备水热生物炭，分析水热生物炭的产率、能量产率、热值、元素组成、表面官能团、表观形貌、平衡含水率等变化等特征。工业分析、元素分析表明，温度是影响水热炭化的重要因素。锯末水热生物炭随温度的升高、时间的延长，C含量增大，O含量降低；生物炭产率、能量产率降低，热值增加。当温度为230℃，时间为30min时，得到生物炭产率为68．78％，能量产率为78．27％，热值为21．57MJ／kg。范式图、红外光谱分析显示，在低温短时炭化时，转化过程以脱水、脱羰基为主。扫描电镜显示水热炭化能破坏生物质微观结构，水热生物炭表面光滑，锯末在170、200℃炭化后有缝隙结构，230℃表面出现孔洞结构。平衡含水率结果表明，水热炭化能提高锯末生物炭的疏水性质，有利于生物炭燃料的保存利用。Using sawdust biomass as raw material, the hydrothermal biochar was prepared by hydrothermal carbonization （HTC） at temperature of 170, 200, 230℃ and time of 15, 30 min. The yield, energy yield, heat value, element contents, surface functional groups, apparent appearance and equilibrium moisture content （EMC） , etc features of hydrothermal biochar were analyzed. Industrial analysis and elemental analysis indicated that the reaction temperature is the most significant factor for hydrothermal carbonization and increasing reaction temperature and time raise C content and heat value, reduce O content, biochar yieht and energy yield. Biochars yield is 68.78%, energy yield is 78.27% and heat value is 21.57 MJ/kg at temperature of 230 ℃ and time of 30 rain. van Krevelen diagram and Fourier transform infrared （FTIR）analyses show that in short-term low-temperature carbonization, the conversion process is based on dehydration, decarbonylation. The scanning electron microscopy （SEM） showed that hydrothermal carbonization can damage the microstructure of biomass, the surface of hydrothermal biochar is smooth. When the sawdust is carbonized at 170, 200℃, the gap structure is appeared on the surface, while the pore structure is appeared on the surface when temperature is set at 230 ℃. The equilibrium moisture content results showed that hydrothermal carbonization can improve the hydrophobic properties of sawdust biochar, is conducive to the preservation and utilization of bioehar fuel.

关 键 词：锯末 生物质 水热 炭化 生物炭 特征 平衡含水率 

分 类 号：TK6[动力工程及工程热物理—生物能]