A Study of Respirable Silica in Underground Coal Mines: Particle Characteristics
Abstract
:1. Introduction
2. Materials and Methods
2.1. Available RCMD Samples
2.2. Silica Particle Surface Analysis
2.2.1. Particle Identification and Dual-Voltage Analysis
2.2.2. Reference Material Selection
2.2.3. Classification Criteria for Free Silica
2.3. Silica Particle Size Analysis
2.3.1. Data from Silica Particle Surface Analysis
2.3.2. Pre-Existing Data
3. Results and Discussion
3.1. Silica Particle Size
3.2. Silica Particle Surface Condition
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Mine | Mine | MSHA | State 2 | Mining | Coal | Mining | Roof | Sampling Location 5 | |||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
reg. 1 | District | Method 3 | Ht. (m) | Ht. (m) | Strata 4 | B | P | R | F | I | Total | ||
10 | CA | 5 | KY | CM | 1–1.2 | 1.8–1.9 | Sh/Sn | 2 | 0 | 1 | 2 | 1 | 6 |
11 | CA | 5 | VA | CM | 0.8 | 1.2–1.3 | Sh | 1 | 1 | 1 | 1 | 0 | 4 |
12 | CA | 5 | VA | CM | 0.8–1.5 | 1.9–2.0 | Sh/Sn | 1 | 1 | 1 | 0 | 1 | 4 |
13 | CA | 5 | VA | LW | 1.5–1.8 | 1.8–2.0 | Sn/Sh | 0 | 0 | 1 | 1 | 2 | 4 |
14 | CA | 5 | VA | CM | 0.6–0.9 | 1.5–1.9 | Sh | 1 | 0 | 0 | 1 | 1 | 3 |
15 | CA | 4 | WV | CM | 0.9–1.2 | 2 | Sh | 1 | 1 | 1 | 0 | 0 | 3 |
16 | NA | 3 | WV | CM | 2.7 | 2.1 | Sh | 1 | 1 | 1 | 1 | 0 | 4 |
17 | NA | 3 | WV | LW | 1.5–1.8 | 2.0–2.3 | Sh | 1 | 1 | 2 | 0 | 2 | 6 |
18 | NA | 3 | WV | CM | 0.7–0.8 | 1.5–1.8 | Sh | 1 | 1 | 1 | 1 | 1 | 5 |
19 | MW | 8 | IL | CM | 1.8–2.0 | 1.9–2.3 | Sh/Lm | 1 | 1 | 2 | 1 | 1 | 6 |
20 | MW | 8 | IL | CM | 1.8–1.9 | 1.8–2.0 | Sh/Lm | 1 | 0 | 0 | 2 | 1 | 4 |
21 | CA | 12 | WV | CM | 0.8–1.0 | 2 | Sh/Sn | 1 | 0 | 1 | 1 | 1 | 4 |
22 | CA | 12 | WV | CM | 0.8 | 1.4 | Sh | 0 | 1 | 0 | 1 | 0 | 2 |
23 | W | 9 | CO | LW | 6.1 | 4.3 | Sh | 0 | 0 | 0 | 0 | 0 | 0 |
24 | W | 9 | CO | LW | 1.8 | 2.1–2.4 | Sh/Sn | 0 | 0 | 1 | 1 | 1 | 3 |
B | P | R | F | I | Total | ||||||||
Total | 12 | 8 | 13 | 13 | 12 | 58 |
Mine Region 1 | Sampling Location 2 | Total | PLD 3 < 0.035 | PLD > 0.035 | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
n 4 | RCS 5 | n | RCS | Mean PLD (#/µm2) | Mean Length (µm) | Mean Change in Si/(Si + Al) 6 | n | RCS | Mean PLD (#/µm 2) | Mean Length (µm) | Mean Change in Si/(Si + Al) | ||
CA | B | 7 | 216 | 6 | 202 | 0.017 | 1.6 | 0.056 | 1 | 14 | 0.051 | 1.5 | 0.013 * |
P | 4 | 162 | 2 | 78 | 0.021 | 1.8 | 0.053 | 2 | 84 | 0.039 | 1.6 | 0.008 * | |
R | 6 | 228 | 4 | 175 | 0.022 | 1.6 | 0.065 | 2 | 53 | 0.039 | 1.8 | 0.044 | |
F | 7 | 191 | 7 | 191 | 0.018 | 1.7 | 0.071 | 0 | 0 | - | - | - | |
I | 6 | 142 | 6 | 142 | 0.014 | 1.8 | 0.045 | 0 | 0 | - | - | - | |
NA | B | 3 | 132 | 3 | 132 | 0.011 | 1.5 | 0.070 | 0 | 0 | - | - | - |
P | 3 | 70 | 0 | 0 | - | - | - | 3 | 70 | 0.043 | 1.1 | 0.016 * | |
R | 4 | 111 | 3 | 88 | 0.021 | 1.5 | 0.054 | 1 | 23 | 0.056 | 1.4 | 0.014 * | |
F | 2 | 7 | 2 | 7 | 0.006 | 1.9 | 0.005 * | 0 | 0 | - | - | - | |
I | 3 | 24 | 3 | 24 | 0.004 | 1.8 | 0.081 | 0 | 0 | - | - | - | |
MW | B | 2 | 55 | 0 | 0 | - | - | - | 2 | 55 | 0.047 | 1.3 | 0.071 |
P | 1 | 43 | 0 | 0 | - | - | - | 1 | 43 | 0.038 | 1.1 | 0.048 | |
R | 2 | 72 | 0 | 0 | - | - | - | 2 | 72 | 0.044 | 1.3 | 0.052 | |
F | 3 | 79 | 2 | 49 | 0.021 | 1.9 | 0.079 | 1 | 30 | 0.049 | 1.4 | 0.066 | |
I | 2 | 24 | 2 | 24 | 0.005 | 2.3 | 0.098 | 0 | 0 | - | - | - | |
W | B | 0 | 0 | 0 | 0 | - | - | - | 0 | 0 | - | - | - |
P | 0 | 0 | 0 | 0 | - | - | - | 0 | 0 | - | - | - | |
R | 1 | 53 | 1 | 53 | 0.032 | 1.2 | 0.014 * | 0 | 0 | - | - | - | |
F | 1 | 27 | 1 | 27 | 0.015 | 1.2 | 0.056 | 0 | 0 | - | - | - | |
I | 1 | 49 | 0 | 0 | - | - | - | 1 | 49 | 0.051 | 1.3 | 0.009 * | |
all Samples | B | 12 | 403 | 9 | 334 | 0.015 | 1.6 | 0.062 | 3 | 69 | 0.048 | 1.3 | 0.059 |
P | 8 | 275 | 2 | 78 | 0.021 | 1.8 | 0.053 | 6 | 197 | 0.040 | 1.3 | 0.020 * | |
R | 13 | 464 | 8 | 316 | 0.023 | 1.5 | 0.053 | 5 | 148 | 0.044 | 1.5 | 0.044 | |
F | 13 | 304 | 12 | 274 | 0.018 | 1.7 | 0.069 | 1 | 30 | 0.049 | 1.4 | 0.066 | |
I | 12 | 239 | 11 | 190 | 0.012 | 1.9 | 0.057 | 1 | 49 | 0.051 | 1.3 | 0.009 |
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Keles, C.; Sarver, E. A Study of Respirable Silica in Underground Coal Mines: Particle Characteristics. Minerals 2022, 12, 1555. https://doi.org/10.3390/min12121555
Keles C, Sarver E. A Study of Respirable Silica in Underground Coal Mines: Particle Characteristics. Minerals. 2022; 12(12):1555. https://doi.org/10.3390/min12121555
Chicago/Turabian StyleKeles, Cigdem, and Emily Sarver. 2022. "A Study of Respirable Silica in Underground Coal Mines: Particle Characteristics" Minerals 12, no. 12: 1555. https://doi.org/10.3390/min12121555