Inerting of coal dust explosions in laboratory- and intermediate-scale chambers

Experiments were performed to compare intermediate-scale (1 m(3)) and laboratory-scale (201) coal dust inerting results. Intermediate-scale inerting levels appear to be lower than laboratory-scale values. This can possibly be attributed to the use of a strong ignition source to initiate the test, which may have overdriven the explosions in the smaller test vessel. Previously reported agreement between the smaller test vessel and full-scale experiments may be due to overdriving in the 201 chamber, leading to high inerting levels similar to those encountered in full-scale tests due to flame acceleration. Additionally, a reduction in the particle size of the rock dust used for inerting has been found to influence the quantity required to prevent an explosion in the 1 m(3) chamber. This agrees with previous work conducted in smaller chambers. (C) 2001 Elsevier Science Ltd. All rights reserved.