In the heart of Beijing, researchers are delving deep into the microscopic world of coal, uncovering secrets that could reshape the energy sector. ZHAO Dan, a scientist at the State Key Laboratory of Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology-Beijing, has been leading a team exploring the micro-mechanical properties of bituminous coal surfaces using advanced atomic force microscopy (AFM) technology. Their findings, published in the Journal of China University of Mining and Technology, offer intriguing insights that could have significant commercial implications.
The team selected four coal samples from different mining areas, each with unique geological conditions. Using AFM with a built-in PF-QNM mode, they scanned the micro surfaces of these samples, revealing striking differences in micro morphology and mechanical properties. “As the degree of metamorphism increased, we observed a significant increase in the number of peaks on the coal’s micro surface,” ZHAO explains. “These peaks provide more adsorption sites for gas, which could have profound implications for gas storage and extraction processes.”
One of the most compelling discoveries was the linear relationship between the average modulus of coal and its degree of metamorphism. This finding suggests that higher-rank coals, which have undergone more metamorphism, are stiffer and more resistant to deformation. This could influence how coal is handled and processed in industrial settings, potentially leading to more efficient and safer mining practices.
The research also shed light on the adhesion properties of coal surfaces. The team found that the surface adhesion force of coal follows an inverted U-shaped distribution with the degree of metamorphism. Medium-rank coals exhibited the highest average surface adhesion force. “This is a crucial finding,” ZHAO notes. “It indicates that the adhesion force is not solely dependent on the degree of metamorphism but is also influenced by the micro surface roughness and the presence of cracks.”
The implications of this research are far-reaching. Understanding the micro-mechanical properties of coal can lead to more accurate modeling of coal behavior under various conditions, improving the efficiency and safety of coal mining and processing. It could also enhance gas adsorption and desorption processes, which are critical for coalbed methane extraction and carbon capture and storage technologies.
As the energy sector continues to evolve, insights from studies like this one will be invaluable. By unraveling the microscopic mysteries of coal, researchers are paving the way for more sustainable and efficient energy solutions. The work of ZHAO Dan and her team, published in the Journal of China University of Mining and Technology, is a testament to the power of advanced technologies like AFM in driving innovation in the energy sector.