Characteristics Analysis of Post-Explosion Coal Dust Samples by X-ray Diffraction

ABSTRACT

Coal dust explosion tests were performed in a 20-L spherical vessel and the post-explosion dust samples were collected for analysis. Various characteristic parameters of each explosion trial were recorded, including maximum pressure, maximum rate of pressure rise, ignition time, and deflagration index. In addition, as a new analytical technique, X-ray diffraction (XRD) was used to analyze the coal dust samples before and after each explosion, and assessments of microcrystalline structures and mineral phases were also performed. The diffraction peaks of post-explosion dust samples were shifted to larger angles and were also sharper and narrower compared to the peaks generated by the original coal dusts. Variations in microcrystalline structural parameters (d₀₀₂ and L₀₀₂) indicated that the post-explosion specimens had a higher degree of crystallinity and a more ordered crystal structure. Differences in mineral components between the pre-explosion and post-explosion samples were also evident, suggesting phase transformations during the explosions. The above results indicate that XRD analysis can be regarded as a reliable tool to study post-explosion coal dust and provide a new insight on further understanding of coal dust explosion characteristics.

KEYWORDS:

• Coal dust explosion
• Microcrystalline structure
• Mineral phase
• X-ray diffraction

Acknowledgments

The authors are grateful to all of the coal mines mentioned in the article for providing experimental coal samples.

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities (2017CXNL02), the program for Innovative Research Team in University of Ministry of Education of China (IRT13098), and a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).