摘要
用氮气等温吸附/脱附法对石油焦燃烧过程中表面形态的变化进行了分析.通过BET法和t-plot法对不同燃尽率的石油焦进行了比表面积和孔容积的测定.结果表明,石油焦燃烧过程中孔隙结构变得发达,比表面积和孔容积较原样明显增大且变化趋势基本一致.验证了石油焦燃烧具有分形动力学的行为特征,用FHH模型求得燃烧中表面分形维数值接近3,表明燃烧反应是在空间网格结构的内、外部同时发生的;同时发现,石油焦表面分形维数与比表面积和孔容积在变化趋势上存在明显差异.
The changes of the surface morphology of petroleum coke during combustion were analyzed by nitrogen adsorption/desorption isotherms. Specific surface areas,pore volumes at different burn-out ratios were determined through BET method and t-plot method respectively. Test results show that during combustion the specific surface area and pore volume increase greatly and have the same change trend. Behavior characteristics of fractal mechanics of the combustion are validated. And the surface fractal dimensions,which are found out to be near 3, are also determined through FHH model, indicating that the combustion reaction occure simultaneously in both inner and outer part of a spatial mesh. The surface fractal dimensions have distinct different change trend from specific surface area and pore volume.
出处
《煤炭转化》
CAS
CSCD
北大核心
2005年第4期30-34,共5页
Coal Conversion
关键词
石油焦
燃尽率
表面形态
分形
petroleum coke, burn-out ratio,surface morphology, fractal
