Recent research published in ‘Meitan xuebao’, or the Journal of Coal Science and Engineering, sheds light on a critical aspect of coal mining safety: the control of gas expansion energy during coal and gas outbursts. This study, led by Jingyu Jiang from the State Key Laboratory of Coal Mine Disaster Prevention and Control in Xuzhou, China, reveals how the speed at which pressure is unloaded from tectonic coal seams can significantly influence the dynamics of these potentially hazardous events.
Gas outbursts, which can pose severe risks to miners and operations, are particularly prevalent in tectonic coal seams. The research team conducted a series of triaxial loading tests, sieving experiments, and gas desorption measurements on samples from the No. 13 Mine of the Pingdingshan coalfield. This region is notorious for its complex geological structures and the challenges they present in managing outburst hazards.
One of the key findings of the study is the relationship between pressure-unloaded speed and gas expansion energy. As Jiang explains, “The unloading of confining pressure not only weakens the coal’s strength but also increases its susceptibility to fragmentation. This fragmentation enhances gas flow pathways, which in turn escalates gas desorption and expansion energy.” The research indicates that increasing the pressure-unloaded speed from 0.01 MPa/s to 0.1 MPa/s can lead to a staggering increase in gas expansion energy by as much as 40%.
This positive feedback cycle is vital for understanding the continuous development of outbursts. The study suggests that as the pressure-unloaded speed increases, the degree of pulverization in coal samples also rises, leading to a higher initial gas desorption volume. This phenomenon creates a self-reinforcing loop that increases the likelihood of outbursts, highlighting the need for careful management of pressure conditions in mining operations.
The implications of this research are significant for the mining sector. By understanding the mechanics behind gas expansion energy and its relationship with pressure-unloaded speed, mining companies can develop more effective strategies to mitigate the risks associated with coal and gas outbursts. Enhanced monitoring and control systems could be implemented to manage pressure unloading rates, ultimately leading to safer working environments and reduced operational disruptions.
As the mining industry continues to evolve, the insights from Jiang’s research could pave the way for innovative safety protocols and technologies. The ability to predict and control outbursts not only protects miners but also ensures the stability and efficiency of coal extraction processes.
This groundbreaking work by Jiang and his team at the State Key Laboratory of Coal Mine Disaster Prevention and Control is a testament to the ongoing efforts to enhance safety in the mining industry. For further information about their research, you can visit lead_author_affiliation.
