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Geotechnical and Geological Engineering

, Volume 37, Issue 6, pp 4815–4823 | Cite as

SEM Image Analysis of Pore and Fracture Characteristics of Lignite Under Temperature Gradient

  • Yue Song
  • Jun XieEmail author
  • Lin Xin
  • Haizheng Fu
Original Paper
  • 64 Downloads

Abstract

In order to study the microstructure characteristics of coal surface after different temperature and thermal effects of lignite, the SEM images of lignite after different temperatures were analyzed by means of theoretical analysis and experimental measurement (SEM microscanning electron microscopy) to studied the characteristics of organic matter and inorganic substance, fracture channel and pore structure. The results show that: At 150 °C, the volume of lignite expands and the pore size becomes larger, and the water loss fracture will be formed; 200 °C is the mutation temperature of the pore structure of lignite; After the temperature reaches 250 °C, the coal skeleton gradually becomes empty, the coal body starts to soften, produces colloidal fragments, and the fissure structure is more irregular; When the temperature reaches 350 °C, the ablation phenomenon is obvious.

Keywords

Coal pyrolysis Lignite Thermal action The SEM test Pores and fissures 

Notes

Acknowledgements

This paper is supported by the National Natural Science Foundation of China (Grant Nos. 51674157, 51504142) and Taishan Scholar Talent Team Support Plan for Advantaged & Unique Discipline Areas and the Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents (No. 2017RCJJ013). National Key R&D Program of China (No. 2018YFC0807900, 2018 YFC0807906); the First-class Discipline Construction Special Fund Project of College of Mining and Safety Engineering, Shandong University of Science and Technology (No. 01AQ02105);  SDUST Research Fund (No. 2018TDJH102).

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.College of Mining and Safety EngineeringShandong University of Science and TechnologyQingdaoChina

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