松木颗粒热解与高温蒸汽气化半焦产率及形貌特征分析

以成型松木颗粒为原料，进行低温热解，研究了热解温度和升温速率对生成的松木半焦产率及官能团的影响。以试验得到的松木半焦进行蒸汽气化试验，对比分析了温度对半焦重整气化形貌特征、比表面积和平均孔径的影响。研究表明：随着热解温度升高，松木半焦脂肪族结构峰消失转化为烃等小分子物质及气化气，进而降低半焦产率。升温速率升高，半焦产率呈先下降后升高的趋势，在800℃升温速率为30K/min时半焦产率最低。不同温度热解和蒸汽气化对比试验表明，温度相对较低时（500℃）热解和蒸汽气化半焦孔隙结构相近，随着温度的升高，蒸汽气化半焦结构发生明显变化，900°C时出现了更小的孔道结构且比表面积增加明显。蒸汽引入使松木半焦和水蒸气发生热解反应的同时发生了脱氢反应，气化半焦形貌出现熔融和烧结现象。

Semi-coke yield and morphology of pine wood particles during pyrolysis and high temperature steam gasification

The formed pine wood pellets were used for low temperature pyrolysis, and the obtained pine wood semi-coke was subjected to steam gasification test. The effects of pyrolysis temperature and heating rate on the yield of pine wood semi-coke and functional groups were studied. The effects of temperature on the morphological characteristics, specific surface area and average pore diameter of semi-coke reforming and gasification are analyzed. The results show that with the increase of pyrolysis temperature, the pine semi-coke aliphatic structure peak disappears into small molecules such as hydrocarbons and gasification gas, and the yield of semi-coke decreases. The heating rate increased, and the semi-coke yield decreased first and then increased. The semi-coke yield reached the lowest when the heating rate was 30K/min at 800°C. The experimental results different temperature pyrolysis and steam gasification experiments show that the pyrolysis and steam gasification semi-coke pore structure are similar when the temperature is relatively low (500°C), and the vapor gasification semi-coke structure changes significantly with the increase of temperature. A smaller pore structure is formed and the specific surface area is increased more significantly at 900°C. It is indicated that the introduction of steam causes the pyrolysis reaction of pine semi-coke and water vapor ,while the dehydrogenation reaction occurs, and the vaporized semi-coke morphology appears to be molten and sintered.