CO source at upper corner of coal mine working face based on coal sample heating experiment and field measurement

To address the phenomenon of frequent CO exceeding at the upper corner of the coal mining face in the Ordos mining area without detected spontaneous combustion in the goaf, this study takes the 8115 working face of Selian No. 1 Mine as the research object. It aims to clarify the specific sources, generation mechanisms, and contribution percentages of CO in this area, providing theoretical support for precise CO control and fire prevention design in the mine. Borehole measurements were conducted to verify the presence of originally stored CO in the coal seam. Coal sample heating experiments were carried out to investigate the temperature characteristics of CO generation. Combined with on-site measurements at multiple points in the roadway, working face, and goaf, the sources and contribution percentages of CO were analyzed using the elimination method. It was confirmed that the coal seam contains originally stored CO, which can be desorbed under natural conditions and oxidizes to generate CO when heated to 45–60°C. The CO at the upper corner of the 8115 working face primarily originates from three sources: mining-induced generation (79%), spontaneous desorption from the coal seam (19%), and exhaust emissions from rubber-tyred vehicles (2%). The dominant source of CO at this working face is mining-induced generation, while originally stored CO desorption and equipment exhaust are secondary sources.