Research on the corresponding relationship between the seepage range and inhibition range of composite long acting blocking liquid in coal body

To address the technical challenge of difficulty in visually monitoring the seepage range and quantitatively determining the inhibition range during the application of in-situ inhibition processes, a fluorescence tracing technique was employed to conduct a visualization monitoring experiment of the seepage range for in-situ inhibition at the Dongtan Coal Mine 6303 working face, and to establish the corresponding relationship between the seepage range and the inhibition range. This study conducted on-site application of in-situ inhibition processes at the Dongtan Coal Mine 63下03 working face. Coal samples were collected from monitoring points 1#, 2#, and 3#, which were drilled perpendicular to the coal wall, based on the actual fluid injection conditions on-site. These samples were then taken to the laboratory for programmed temperature rise experiments and fluorescence spectrophotometry experiments. The corresponding relationship between the seepage range and the inhibition range was constructed using the inhibition rates and fluorescence intensities obtained from the experiments. The results indicate that the inhibition rates at monitoring points 1#, 2#, and 3# exhibit similar trends, showing an initial increase followed by a decrease with increasing drilling depth. The maximum inhibition effect is achieved at a depth of 8 m for all three points. Monitoring point 1# has an inhibitory effect at depths of 8–16 m, while point 2# shows effectiveness at 8–14 m. No inhibitory effect was observed in the samples taken from monitoring point 3#. By fitting the relationship between the inhibition rate and fluorescence intensity, a relationship equation based on full-scale fluorescence intensity and inhibition rate was obtained, determining the seepage range and inhibition range of the inhibitory fluid within the coal body and their corresponding relationship, which plays an important guiding role in the efficient implementation of coal seam fluid injection.