Chow Judith C, Watson John G, Wang Xiaoliang, Abbasi Behrooz, Reed Wm Randolph, Parks David
Division of Atmospheric Sciences, Desert Research Institute, Reno, NV 89511, USA.
Department of Mining and Metallurgical Engineering, University of Nevada, Reno, NV 89557, USA.
Minerals (Basel). 2022 Oct 18;12(10). doi: 10.3390/min12101314.
This review considers the use of filters to sample air in mining workplace environments for dust concentration measurement and subsequent analysis of hazardous contaminants, especially respirable crystalline silica (RCS) on filters compatible with wearable personal dust monitors (PDM). The review summarizes filter vendors, sizes, costs, chemical and physical properties, and information available on filter modeling, laboratory testing, and field performance. Filter media testing and selection should consider the characteristics required for mass by gravimetry in addition to RCS quantification by Fourier-transform infrared (FTIR) or Raman spectroscopic analysis. For mass determination, the filters need to have high filtration efficiency (≥99% for the most penetrable particle sizes) and a reasonable pressure drop (up to 16.7 kPa) to accommodate high dust loading. Additional requirements include: negligible uptake of water vapor and gaseous volatile compounds; adequate particle adhesion as a function of particle loading; sufficient particle loading capacity to form a stable particle deposit layer during sampling in wet and dusty environments; mechanical strength to withstand vibrations and pressure drops across the filter; and appropriate filter mass compatible with the tapered element oscillating microbalance. FTIR and Raman measurements require filters to be free of spectral interference. Furthermore, because the irradiated area does not completely cover the sample deposit, particles should be uniformly deposited on the filter.
本综述探讨了在采矿工作场所环境中使用过滤器采集空气样本，以测量粉尘浓度并随后分析有害污染物，特别是与可穿戴式个人粉尘监测仪（PDM）兼容的过滤器上的可吸入结晶二氧化硅（RCS）。该综述总结了过滤器供应商、尺寸、成本、化学和物理性质，以及有关过滤器建模、实验室测试和现场性能的可用信息。除了通过傅里叶变换红外（FTIR）或拉曼光谱分析对RCS进行定量外，过滤介质的测试和选择还应考虑重量法测定质量所需的特性。对于质量测定，过滤器需要具有高过滤效率（对于最易穿透粒径≥99%）和合理的压降（高达16.7 kPa），以适应高粉尘负荷。其他要求包括：水蒸气和气态挥发性化合物的吸附可忽略不计；颗粒附着力随颗粒负荷的变化适当；在潮湿和多尘环境中采样期间具有足够的颗粒负荷能力，以形成稳定的颗粒沉积层；具有承受过滤器振动和压降的机械强度；以及与锥形元件振荡微天平兼容的适当过滤器质量。FTIR和拉曼测量要求过滤器无光谱干扰。此外，由于照射区域不能完全覆盖样品沉积物，颗粒应均匀沉积在过滤器上。
