the flame propagation through a coal dust-air mixture in a spherical vessel was studied by means of a one-dimensional, arrhenius-type kinetics and quasi-steady model. the model includes the evaporation of the volatile matter of dust particles into a known gaseous fuel (methane) and the single-stage reaction of the gas-phase combustion. effect of venting devices as safety idea and the radiation ...

Rock dusting to prevent coal dust explosions has been in widespread use in U.S. underground coal mines since the early 1900s. Underground coal mining technology has changed significantly over this same time period, becoming highly mechanized and produces finer coal dust particles which are more explosive. Despite the advances in mining technology, mine-wide dust sampling practices have remained...

Dust explosions always claim lives and cause huge financial losses. Dust explosion risk can be prevented by inherently safer design or mitigated by engineering protective system. Design of explosion prevention and protection needs comprehensive knowledge and data on the process, workshop, equipment, and combustible materials. The knowledge includes standards, expertise of experts, and practical...

Explosibility and ignitability studies of air/cork dust mixtures were conducted in a near-spherical 22.7 L explosibility test chamber using pyrotechnic ignitors and in a furnace of 1.23 L. The suspension dust burned as air-dispersed dust clouds and the uniformity of the dispersion inside the chamber was evaluated through optical dust probes. The range of tested particle sizes went from a mass m...

Coal dust explosions in underground coal mines are pre­ vented by a generous application of rock dust (usually lime­ stone). If an explosion should occur, the rock dust disperses, mixes with the coal dust and prevents fl ame propagation by acting as a thermal inhibitor or heat sink. To investigate this process in more detail, a number of ex­ plosion experiments using various coal dust and limes...

In situ measurements of the sizes and concentrations of dust particles generated by the detonation of high explosives in clay soil near Leesville, La., sandy clay soil near Huntsville, Ala., and sandy soils near Orogrande, N.M. are reported. Measurements were generally made within 1 m of the surface (in one case 10 m) at distances ranging from 10 to approximately 50 m from the detonation point ...

Investigation of the ignition behavior (minimum ignition temperature (MIT)) of hybrid mixtures of dusts and gases has been undertaken. This was achieved by performing series of test in the modified Godbert-Greenwald furnace. The materials used are, gases (methane, propane and hydrogen) and dust (starch, lycopodium, toner, wood and CN4 (mixture of bituminous and brown coal)). The test protocol f...