树皮体的化学结构和煤岩学特征特性研究

Barkinite has not been recognized by international committee for coal and organic petrology (ICCP), which results from no thorough studies on coal petrologic and chemical structural characteristics of barkinite. Barkinite in this works from some typical areas, e.g. Leping in Jiangxi province, were selected. Both the chemical structural and coal petrologic characteristics of barkinite were discussed by using some macro- and micro- analytical techniques as well as in-situ and offline testing methods based on some theoretic, e.g. coal petrology, coal chemistry, and coal geochemistry. The chemical structural characteristics of barkinite, cutinite, and suberinite were studied from various aspects, different coal ranks and heating treatment, etc. and, corresponding, the morphologic and coal petrologic features were also detailed observed. Furthermore, the differences of chemical structural and optical features between barkinite, cutinite, and suberinite were discussed, which can demonstrate the specialities of barkinite. This works can provide a foundation for explaining the position of barkinite in international classification of coal petrology.

树皮体仍未得到国际煤和有机岩学委员会的认可，受制于树皮体的煤岩学和化学结构特征研究不透彻。课题将以江西乐平等典型地区的树皮体为研究对象，综合运用煤岩学、煤化学、煤地球化学等理论，采用宏观与微区分析技术相结合、原位与离线测试方法相匹配等方法，系统分析树皮体的化学结构和煤岩学特征。从不同煤级、受热变化等多角度，通过测试分析结构参数与构建模型，深入探讨树皮体、角质体和木栓质体的化学结构特征；精细剖析树皮体、角质体和木栓质体的形貌特征和煤岩学特征。并进而寻找树皮体与角质体、木栓质体的化学结构特征和光学特征异同，论证树皮体的特性。此研究能为树皮体的国际煤岩学定位奠定基础。

树皮体是我国煤中特有显微组分，但至今未得到国际煤和有机岩石学委员会认可，关键在于树皮体的化学结构和煤岩学特征特性不清。课题以典型地区树皮体为研究对象，应用在线加热高分辨率透射电镜、原子力显微镜等分析技术手段，系统研究了树皮体的化学结构特征、形貌特征、形态特征和孢粉特征，并与镜质体、孢子体和树脂体等显微组分进行了比较。首次成功分离得到乐平鸣山煤矿B3煤层中的孢粉，初步观察主要是蕨类植物孢子，孢子类型相当丰富。树皮体不规则状态开始变为规则状态的温度为250℃，其芳香层片结构在375℃时完全规则排列。镜质组化学结构改变的温度比树皮体的推迟50℃。在450℃时，树皮体的萘含量高于镜质体，而2 × 2 芳香层片和 3 × 3 芳香层片比镜质体低。化学组成和化学结构特征证明树皮体具有类脂组特征。AFM结果表明随着树皮煤演化程度的加深，树皮体的表面形貌变化从纤维状形貌特征到不规则形貌特征，方向性逐渐增强。当镜质组反射率达到1.12%时，树皮体的形貌特征与镜质体的类似。基于树皮体在光学显微镜下的形态，把树皮体的形态分成了五种类型，为研究树皮体的形成条件提供了支持。依托此项目的研究成果，为树皮体的国际煤岩学定位提供数据支持，其成果已经被国际煤岩学委员会引用。同时，也可以揭示不同显微组分之间热行为特征差异机理，进而为煤的高效合理利用提供可靠的理论根据。