Experimental investigation and mechanistic analysis of PMMA dust explosion suppression by a novel three-phase-gel foam

Dust explosions represent a highly hazardous incident in industrial production. Polymethyl Methacrylate (PMMA), as a widely utilized synthetic material, poses significant explosion risks in its dust form. Addressing the limitations of current dust explosion suppressants, such as their simple composition and limited effectiveness, this study investigates the suppression performance and mechanism of a novel three-phase-gel foam on PMMA dust explosions. Explosion characteristics were analyzed across PMMA particle sizes (200 to 2000 mesh) and concentrations (128–641 g/m³). Suppression experiments comparing water mist and the new foam were conducted for 500 and 2000 mesh powders. Results show that finer particles and higher concentrations increase explosion intensity and risk of secondary explosions. The three-phase-gel foam exhibited superior suppression to water mist, especially at 500 mesh and 128 g/m³, achieving a 32.09 % reduction in flame length and 59.73 % in peak velocity, with appearance times extended by 332 ms and 248 ms. Mechanism analysis via TG-DSC, SEM, and XRD revealed that the foam’s thermal stability, adhesion, and multi-phase structure form an effective barrier, enhance cooling, and inhibit radical chain reactions. These findings demonstrate the foam’s strong potential as a multi-mechanism dust explosion suppressant, offering practical value for industrial safety.