Chad V. Mashuga

Carbon nanofiber explosion violence and thermal stability

Due to tremendous efforts in experimental explosion characterizations of combustible dust and better understanding of their influential factors, modern industry can design better safeguards to prevent and mitigate dust explosions. However, when it comes to nanomaterials, research on their explosion characterizations is still coming into focus despite ever-expanding production and applications. Engineered nanomaterials can have a variety of unique properties after various production and processing methods, making it difficult to analyze the reported experimental data and identify explosion factors. In this study, explosibility tests of nine commercially available carbon nanofibers (CNFs) were conducted in a customized 36-L dust explosion vessel. Test results demonstrated that a mechanical milling process commonly used on CNFs could increase the deflagration index, while another common process, annealing process, could decrease the explosion violence with significant influence on the deflagration index and modest influence on maximum overpressure. The effects of three influential factors—dust concentration, graphite perfection, and agglomerate size—were analyzed. In addition, this study proposed an improved method for estimating the maximum overpressure from dust explosion as well as a demonstration of influential factors on [dP/dt]maxV1/3.