Evaluation of ventilation network through hybrid analytical-numerical approach in underground working block

Abstract

The mine environment is complex and highly dynamic due to the developments over time and surrounding climatic changes. Heedlessness to supply adequate quantity and quality of air will catalyse short and long-term ailments to the workers. Therefore, this study emerges as the new research frontier in incorporating software-assisted numerical simulation with analytical computations. This investigation assesses the existing ventilation parameters at the Bogala underground graphite mine for the propriety of the working environment. The uttermost bottom block between 240 and 275 fathoms (FM) levels was examined. The parameters were obtained through the in-field ventilation survey. Measured air quantity, psychometry, and air quality values were analysed and fed to the computer-simulated model. Moreover, the reentry time for a development drive at 275 FM level was estimated using the throwback method. Adequacy assessment unveils that all the parameters besides air quality are inadequate at most stations for optimal mine conditions to attain maximum efficiency. Furthermore, the re-entry time after the development blast at the selected drive is meager and necessitates re-calculation for each blast. Moreover, stale air mixing and air recirculation are extant at 240 FM and 275 FM levels, respectively. Thus, mine ventilation at Bogala needs to be optimised, admitting workers' health, safety and comfort, and productivity of the mine.