Verification of the oxygen consumption rate of the remaining coal in the gob by research and experiment

ABSTRACT

Oxygen consumption rate is an important index to evaluate the oxidation performance of coal, and it usually has an exponential relationship with temperature. However, during the temperature-rising oxidation experiment, it was found that as the temperature increased, the oxygen concentration at the outlet of the reaction tank would gradually decrease to a certain value, which caused the oxygen consumption rate to gradually approach a certain constant and thus be unable to accurately express the oxygen consumption characteristics of coal. To solve this problem, we introduce a new parameter and propose a new calculation model. We conducted low-temperature oxidation experiments on coal samples from Yang Chang Wan Mine (YCW) and An Ze (AZ) Mines under different oxygen concentrations and different gas flow conditions. Experimental results show that the new model has an exponential relationship with temperature for the same coal sample. This relationship depends on the inherent properties of the coal and is independent of the oxygen concentration and flow rate. Through exponential fitting, the determination coefficients of the new models for the two coal samples under different oxygen concentrations are increased by 7.55% and 3.55%, respectively, compared with the old model; under different flow conditions, the coefficients of determination are increased by 2.93% and 6.08%, respectively. These results indicate that the new model can more accurately express the oxidation characteristics of coal compared to the old model, providing a more accurate theoretical basis for future studies on the spontaneous combustion of coal.

KEYWORDS:

• Oxygen concentrations
• flowrates
• oxygen consumption rate
• self-ignition characteristics

Acknowledgements

We thank the efforts of the editor and the anonymous reviewers who offered insightful criticism and recommendations to advance our research. The authors are extremely appreciative of the help from the China Scholarship Council (File: 202206430069).

Disclosure statement

The authors reaffirm that they are not aware of any personal or financial conflicts that might have appeared to affect the research described in this paper.

Credit authorship contribution statement

Yueping Qin: Funding acquisition, Project administration. Changqing Chu: Writing original draft preparation, Conceptualization, Methodology. Linxiao Yan: Data curation, Formal analysis. Yi Xu: Resources, Investigation. Wenjie Guo: Formal analysis. Qifan Fan Conceptualization Ju He: Visualization, Supervision. Fei Li: Investigation.

Additional information

Funding

These tasks were completed with the help of the National Natural Science Foundation of China [grant numbers 52074303 and 51874315].

Notes on contributors

Yueping Qin

Yueping Qin is a professor at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine ventilation, mine fire, mine gas and cooling technology in mine.

Changqing Chu

Changqing Chu is a Master candidate at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine fire.

Linxiao Yan

Linxiao Yan is a PhD candidate at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine fire.

Yi Xu

Yi Xu is a Master candidate at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine fire.

Wenjie Guo

Wenjie Guo is a PhD candidate at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine fire.

Qifan Fan

Qifan Fan is a Master candidate at the School of Emergency Management and Safety Engineering, China University of Mining & Technology, Beijing. His research focuses on mine fire.

Ju He

Ju He is a Master candidate at the School of Law, Guangxi University, Nanning. Her research focuses on Law and Visualization.

Fei Li

Fei Li is a Master candidate at the School of Electromechanical and Information Engineering, China University of Mining & Technology, Beijing. His research focuses on computer and Investigation.