Sensitivity Analysis of Dust Explosion Consequences in a Roller Mill using FLACS-DustEx

Abstract

The current study is a continuation of the work reported by Wingerden et al. (2011). Dust explosion experiments were performed in a roller mill (capacity 36 metric tonnes coal/hour; internal volume 23.2 m3) connected to a coal feeder located on top of the mill. Coal and wood dust clouds were generated in the mill/coal feeder combination by pneumatic injection. The concentrations investigated were however not chosen to be optimal: instead lean dust-air mixtures were investigated. The presented results are those of a sensitivity analysis using optimal dust-air mixtures. The investigation was performed with the FLACS-DustEx CFD tool: a dedicated tool for simulating the course of dust explosions in complex geometries. The following parameters were varied: type of dust, ignition source location, ignition delay time (assuming pneumatic injection) and vent opening size. The sensitivity study indicates the maximum explosion pressure that can arise in a roller mill when conditions are chosen to be optimal/worst case.