Enhanced removal of high-temperature industrial particles via optimized spray droplet collision: Mechanisms and...

Industrial particles readily accumulate toxic pollutants, posing severe threats to both the environment and human health. The significant temperature variations (ranging from 20 to 500°C) in particles emitted from different industrial processes challenge the applicability of existing spray dust suppression guidelines. However, the interaction mechanisms remain poorly understood due to the difficulty in capturing micron-scale spray droplet collisions with high-temperature particles. This study elucidates the collision mechanisms between industrial particles at varying temperatures and spray droplets, establishing a comprehensive parameter spectrum and spray strategies for high-temperature particle capture. Results demonstrate that a novel dynamic contact angle model incorporating spherical temperature effects achieves a mean error of 7.43 %, thereby enabling precise investigation of micron-scale collision dynamics. Unlike ambient-temperature particles, high-temperature particles exhibit significantly suppressed wettability. Furthermore, two efficient dust suppression pathways were identified: high-speed sprays capable of achieving adhesion, immersion, or detachment sedimentation, and low-speed micro-droplet sprays that promote deposition. Notably, the optimal droplet Weber number for 293.15 K particles is nearly 26 times higher than that for 448.15 K particles, highlighting the need for temperature-specific spray designs. This study provides a robust theoretical foundation for the efficient spray-based control of hazardous substances in high-temperature industrial particles.