Assessment of Sub-micrometer-Sized Particles with Practical Activities in an Underground Coal Mine
Yi-Hsuan Chen1, Alejandro Munoz1, Connor Krause1
1Department of Environmental Health Sciences, University of California, Los Angeles, Los Angeles, CA USA.
Mining, Metallurgy & Exploration
|December 24, 2024
Summary
Airborne particle concentrations, especially sub-micrometer sizes, were significantly higher in underground coal mine belt entries. Harmful elements like Ca, Cu, Si, Al, Fe, and Co were detected in inhaled dust.
Area of Science:
- Occupational Health and Safety
- Environmental Science
- Mining Engineering
Background:
- Underground coal mines pose risks from airborne particles.
- Understanding particle size distribution and composition is crucial for miner health.
Purpose of the Study:
- To characterize airborne particles, particularly sub-micrometer sizes, in underground coal mines.
- To compare particle concentrations across different mine locations.
- To identify the elemental composition of inhaled particles.
Main Methods:
- Utilized real-time instruments (RTIs) for particle number concentration.
- Employed gravimetric samplers (inhalable, respirable cyclone, Tsai diffusion sampler) for mass concentration and characterization.
- Analyzed particle morphology and composition using electron microscopy (EM).
Main Results:
- Belt entry showed a nine-fold higher particle number concentration than other areas.
- Elevated submicron and nanoparticle levels (0.54–1.55 mg/m³) were found in belt conveyor drifts.
- Detected harmful elements including Ca, Cu, Si, Al, Fe, and Co in inhaled particles.
Conclusions:
- Significant presence of sub-micrometer and nanoparticles (<300 nm) in coal mines linked to mining activities.
- Belt entry areas are hotspots for high particle concentrations.
- Inhaled coal mine dust contains harmful elements posing health risks to miners.
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