Study On The Fractal Analysis Of Embedded Structure Of The Coals

The embedded structure model of coal is a new systemic theory of the coal structure, but for now, there is no research from image perspective to prove, analysis and study the morphology of particles and the existing of the embedded structure of the so-called heavy component, dense medium component, and loose medium component in this theory directly. This paper attempts to solve this question, and provids the most direct and effective evidence of the embedded structure model. This paper based on the separation experiment, has a test and analysis on nine different coals and components by AFM and TEM, and also has a contrastive study on the microscopic morphology, roughness and fractal dimension etc to observe the corresponding rule with the degree of coal metamorphism. And the results suggested:The coals from the lignite coal to anthracite coal are all made up of two types of particles, the diameter of most particles is between 50 and 80 nm, and the particles consists the basement in dense accumulation way; in the basement, there embedded fewer and larger particles with the diameter between 80 and 120 nm. In the components, the particles of coal heavy component has the smallest diameter and the diameter is about 50 nm, the dense medium component has the largest particles and the diameter is about 120 nm, the diameter of loose medium component particles is between 80 and 100 nm.The raw coal formed by various types of molecules disseminated through original structural rule, it’s Ds increased with the rising of coal rank, and the Ds can be divided into three intervals, lignite’s is the minimum Ds(1.48), lean coal and anthracite have the maximum Ds(1.75-1.80), while other bituminous coals are in the middle position(1.57-1.65), when using Vdaf to reflect the coal rank, the two linear ranges between Ds and Vdaf can be got, the Ds of low rank coal which metamorphic grade is lower than gas coal is less than 1.61, and the linear relationship is Ds=2.13-0.012Vdaf(R2=0.90), while the Ds of high rank coal that metamorphic grade is higher than fat coal is bigger than 1.61, the linear relationship is Ds=1.97-0.013Vdaf(R2=0.99). The Ds of all components are largely independent of coal rank, and the two ranges between Ds and Vdaf divided by Ds=1.61 are still exist. The Ds of all rank coals is between 1.55 and 1.65, and has the fundamental law that heavy component > loose medium component> dense medium component.The particles(size =120 nm) formed dense medium component are stacked by accumulations whose size is about 30-50 nm, and the accumulations were formed by the single nanoparticle(size ≈3-5 nm). Aliphatic part accounts for a high proportion in accumulations, and the most are in straight chain to accumulate the ordered molecules and produce stable lamellar and grain structures, the lamellar spacing is 3-3.5 ?.At last, this paper does something to improve the embedded structure model of coal.There are forty figures, eight tables and one hundred and seventeen references in this paper.