Research of Coal Pores and Integrity Evaluation Method Based on Fractal Theory

Abstract:

Coal is a natural porous media, its porosity and structural integrity influenced the gas adsorption and desorption characteristics greatly, as well as physical and mechanical properties of coal. Scanning electron microscopy (SEM) is applied to acquire SEM image of four kinds of coal samples at different zoom levels, and the box dimension can be worked out based on the pore preprocessing of SEM images. Then, the numerical value of box dimension is used to describe the development degree of the four kinds of coal sample and four development degrees’ sequence. At last, the intrinsic relevance between fractal dimension and other parameters is analyzed through mathematic method. The results show as follows: coal sample has self-similarity characteristic; the fractal dimension is related to both the total number of pores and porosity degree; the data of the coal pore, analyzed through fractal dimension, are consistent with that through traditional method; what’s more, fractal dimension has more advantages in describing accuracy and simplicity.

• Periodical: Applied Mechanics and Materials (Volumes 670-671)
• Pages: 258-262
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.670-671.258
• Online since: October 2014
• Authors: Ji Li*, Xin Wu
• Keywords: CoAl, Evaluation, Fractal Dimension, Pore, SEM

References

[1] ZHANG Zhangcun, Experimental Research on Moisture Effects on the Gas Absorption Speciality of Coal. Beijing: China Coal Research Institute, (2004).

[2] SU Xianbo, CHEN Jiangfeng, SUN Junming. Coalbed methane geology and exploration. Beijing: Science Press, (2001).

[3] SHANG Shuxun, ZHU Yanming, ZHANG Shiying. Solid-gas Interaction Mechanism of Coal-adsorbed Gas (Ⅰ) - Coal Pore Structure and Solid-gas Interaction. Tural Gas Industry, 2005, vol. 25, p.13–16.

[4] ZHANG Hui, LI Xiaoyan, HAO Qi, Scanning electron microscopy research of China's coal. Beijing: Geological Press, (2003).

[5] SUN Weiji. A Study of the Transport Mechanism and Model of Coalbed Methane on Different Pore Scale. Fuxin: LiaoNing Technical University, (2007).

[6] ZHANG Guangyang, HU Yaohua, TAN Xueshu. Analysis of Micrdstructure of Coal from Nantong Colliery". Xi'an: Journal of Xi, an Mining Institute, 1995, vol. 15, p.320–330.

[7] ZHANG Hongri, WANG Chuanyun, Microscopic Characteristics of Burst Coal seams". Xi, an: Coal Geology & Exploration, 2000, vol. 28: pp.31-33.

[8] ZHAO Fenghua, REN Deyi, The Application of High-resolution Transmission Electron Microscopy to Study the Structures of Coal Macerals,. Beijing: Geology Review, 1995, vol. 41, pp.564-570.

[9] CHENG Mingjun, Research on the Permeability of Coal and the Simulation of Coal and Gas Outburst Process. Chongqing: Chongqing University, (2008).

[10] ZHANG Yutao, TU Deming, HONG Xiaoxing, Features of fissure sharp in coal borehole and variation law with temperature,. Beijing: Coal Science and Technology, 2007, vol. 35, pp.73-76.

[11] WEN Zhiying, The mathematical basis of fractal geometry. Shanghai: Shanghai Science and Technology Education Press, (2000).

[12] LIU Shida, LIU Shishi, Fractal theory and fractal dimension Citation. Beijing: Meteorological Press, (1993).

[13] LIU Shunzhong, RONG Limin, JING Lifang, Non-parametric statistics and SPSS software applications Wuhang: Wuhan university Press, (2008).

[14] YANG Hu, Liu Qiongshun, ZHONG Bo, Mathematical Statistics. Beijing: Higher Education Press, (2004).