Mining Program Area: Ventilation
Mine worker safety and health is dependent on the ventilation system operating properly. Ventilation mitigates issues such as poisonous gasses, harmful dust, and temperature, and maintains a life-supporting atmosphere for workers. Maintaining adequate ventilation also reduces the risk of an explosive atmosphere occurring.
The Ventilation Program seeks to answer the following research questions:
- Can we quantify the movement of methane gas between existing gas reservoirs (gas-bearing strata, sealed areas) and active mine workings, and what are the effects of such movements on the mine ventilation system? In what ways does the presence of a low barometric pressure event affect this movement?
- What are the limitations of current longwall bleeder designs for controlling explosive methane levels? Can we develop improved bleeder designs to more effectively handle the increased methane quantities anticipated from larger longwall gobs and gob districts?
- Can continuous air velocity measurements be used to recognize potential instability of a mine ventilation system, and how can this information help locate the cause and impact of abnormal airflow conditions?
- In continuous mining operations, can a secondary methanometer located on the mining machine provide improved warning of hazardous gas conditions at the face, and where should this monitor be placed?
- How can we best use booster fans and controlled district recirculation in metal/nonmetal (M/NM) operations to improve control of gases, such as methane, and airborne contaminants, such as dust and diesel particulate matter (DPM)?
- Can integrated fan/filter arrangements be used to control harmful levels of dust and DPM at active faces in large-opening operations?
Increasing awareness of underground mine ventilation issues empowers mine workers to proactively address changing ventilation conditions caused by both mining and geological issues.
The National Institute for Occupational Safety and Health’s (NIOSH) Office of Mine Safety and Health Research (OMSHR) has incorporated computer modeling using computational fluid dynamics (CFD), which helps researchers understand air flow in different mining situations: for example, in a continuous miner face or around a longwall tailgate corner.
OMSHR currently has projects in coal and M/NM ventilation and is also funding a project to develop a laser-based methanometer for remote detection of methane gas. These research activities are a necessary addition for effective OMSHR research, because they provide resources in specific program areas outside of our expertise. OMSHR is also funding seven universities to build competency in the ventilation sciences: University of Nevada-Reno, University of Alaska Fairbanks, Colorado School of Mines, University of Utah, Missouri University of Science and Technology, University of Kentucky, and Virginia Tech.
The program’s significant milestones include designs to improve the performance of longwall bleeders, the integration of data from continuous airflow monitoring into an assessment of ventilation performance, and development of guidelines for using booster fans and controlled district recirculation to improve ventilation in M/NM operations.