Department of Chemical and Biological Work Environment, National Institute of Occupational Health, P.O.Box 5330 Majorstuen, NO-0304 Oslo, Norway.
Environ Sci Process Impacts. 2019 Mar 20;21(3):564-574. doi: 10.1039/c8em00518d.
The global SiC market is projected to grow in the coming years, and research on potential health effects as well as epidemiological studies is therefore of importance. A detailed characterization in terms of the phase composition, morphology and mixing state of airborne PM is still missing, though highly necessary to identify sources and to understand the risk factors in this industry. Particles in the size range of 10 nm to 10 µm were collected with a 13-stage NanoMOUDI impactor in the Acheson Furnace Hall as well as in processing departments during two sampling campaigns. Particle mass concentrations, including the fraction of ultrafine particles (UFPs), were lower in the processing departments in comparison to those in the Acheson Furnace Hall. The particle number size distribution measured with a scanning mobility particle sizer confirmed the low amount of UFPs in the processing departments compared to the furnace hall. Significant differences in the particle mass concentration and distribution were observed in the Acheson Furnace Hall during the two sampling campaigns. The PM size distribution depends upon the sampling location, on the cycle of the nearby furnaces and on special incidents occurring during a furnace run. Scanning and transmission electron microscopy (SEM and TEM) showed that the size range of 0.32-10 µm (aerodynamic diameter) is dominated by carbon (C)-rich particles, which were identified as petroleum coke, graphite, soot and amorphous spherical C-rich particles. Soot was further classified into three types based on the primary particle size, morphology and composition. Diesel-powered vehicles, pyrolysis of petroleum coke and incomplete combustion of volatile components from this pyrolysis are suggested as sources of different soot particle types. Amorphous spherical C-rich particles were also sub-classified based on their morphology and composition as tar balls (TBs) and C-spherical type 2. The amount of SiC fibers and crystalline SiO2 was found to be low. In the size fraction below 0.32 µm (aerodynamic diameter), sulphur (S)-rich particles dominate. This knowledge of the particle size distribution, and chemical and physical properties of the PM occurring in the SiC production is fundamental for an appropriate risk assessment, and these findings should have implications for future epidemiological studies and for the mitigation of worker exposure.
全球碳化硅市场预计在未来几年内增长，因此研究潜在的健康影响以及流行病学研究非常重要。尽管对于识别来源和理解该行业的风险因素至关重要，但空气中 PM 的相组成、形态和混合状态的详细特征仍然缺失。在阿克森炉大厅以及在两个采样活动期间的加工部门中，使用 13 级纳米 MOUDI 撞击器收集了粒径范围为 10nm 至 10µm 的颗粒。与阿克森炉大厅相比，在加工部门中，颗粒质量浓度，包括超细颗粒（UFPs）的分数较低。使用扫描迁移率颗粒尺寸分析仪测量的颗粒数尺寸分布证实了与炉大厅相比，加工部门中 UFPs 的数量较少。在两个采样活动期间，阿克森炉大厅中观察到颗粒质量浓度和分布的显著差异。PM 粒径分布取决于采样位置、附近炉的周期以及炉运行期间发生的特殊事件。扫描和透射电子显微镜（SEM 和 TEM）表明，0.32-10µm（空气动力学直径）范围内的颗粒主要由富碳（C）颗粒组成，这些颗粒被鉴定为石油焦、石墨、烟尘和无定形球形富 C 颗粒。烟尘根据初级颗粒尺寸、形态和组成进一步分为三种类型。建议不同烟尘颗粒类型的来源为柴油动力车辆、石油焦的热解以及该热解过程中挥发性成分的不完全燃烧。还根据其形态和组成将无定形球形富 C 颗粒进一步细分为焦油球（TBs）和 C-球形类型 2。发现 SiC 纤维和结晶二氧化硅的含量较低。在 0.32µm（空气动力学直径）以下的粒径范围内，富硫（S）颗粒占主导地位。对 SiC 生产中出现的 PM 的粒径分布、化学和物理特性的了解是进行适当风险评估的基础，这些发现应该对未来的流行病学研究和减轻工人暴露产生影响。
