Summary of wind speed observation data along 1304 working face and intake and return air roadway
Description
This is a data summary that includes two parts: data from the closed oxygen consumption experiments of the 1304 working face coal samples, and data observations of the airflow velocities along the intake and return airways of the 1304 working face. The data from the closed oxygen consumption experiments of the 1304 working face coal samples were obtained by conducting sealed oxygen consumption tests. In order to determine the coal sample’s oxygen consumption rate at different oxygen concentrations, the coal sample was sealed in a container, and the air inside the container was circulated using an air pump to ensure sufficient contact between the coal sample and the air. As the coal sample continuously oxidized, the oxygen inside the container was consumed, and the volume fraction of oxygen inside the container was monitored and recorded in real-time. The oxygen consumption rate eventually reached a steady state. By analyzing the unique pattern of oxygen concentration changes during the coal-oxygen consumption process, the relationship between oxygen volume fraction and time was obtained. It was observed that as time increased, the oxygen volume fraction exhibited a negative exponential function relationship. Therefore, the critical oxygen consumption rate of the coal sample could be determined. The data summary also includes observations of airflow velocities along the intake and return airways of the 1304 working face. The measurement route is as follows: starting from the transport roadway to the intake corner of the working face, there were a total of 89 measurement points. Then, reaching the return corner of the working face, there were 26 measurement points. Finally, reaching the return airway, there were 60 measurement points. The measurement method for airflow velocity involved dense point measurements using an anemometer and a stopwatch. The overall data analysis, after removing outliers caused by underground tunnel structures, enabled the identification of the overall pattern of airflow velocity changes along the entire roadway. Combining the data from the working face and the intake and return airways, it was possible to make accurate inferences about the air leakage conditions in the airways. The overall trend of airflow velocity changes along the route was quite evident. Analyzing the curve trend revealed that in the case of insufficient ventilation in the two headings, the primary air leakage from the working face to the goaf occurred through the intake corner. Additionally, there was some air leakage from the overlying 12# coal mining subsidence area above the 1304 working face, which flowed back into the return airway through the intake airway, leading to a noticeable increase in airflow in the return airway section.