Combustible solids

Table 6.2 Dust explosion characteristics of combustible solids...

Mixing of flammable materials and combustible solids with strong oxidizing agents ... 

Precautions to be taken on completion of the work, e.g. a fire-watch following welding in an area containing combustible solids. 

Fire Hazards - Flash Point Not pertinent (combustible solid) Flammable Limits in Air (%) Not pertinent Fire Extinguishing Agents Water, foam Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Toxic oxides of nitrogen may be formed in a fire Behavior in Fire Not pertinent Ignition Temperature Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. 

The burning of fuels involves a combination of thermal decomposition (dominant when combusting solid fuels) and hydroxylation (dominant when combusting gaseous fuels), as part of the overall process. 

The utilization of combustible solid materials in propulsion devices is by no means a modern development. There is evidence that the first rockets were used in India around 2000 b.c., and the Chinese are known to have experimented with pellatized gun powder in rockets during the Tang dynasty... 

All combustible solids can create a dust explosion hazard if dispersed in air as a line dust within certain concentration limits. Refer to Table 5.2. The hazard increases with decreasing size. 

Increasing the surface area of a combustible solid enhances the ease of ignition. Solid particles less than about 10 pm in diameter settle slowly in air and comprise float dust . Such particles behave, in some ways, similarly to gas and, if the solid is combustible, a flammable dust—air mixture containing a distribution of particle sizes can form within certain limits. 

Combustion/ Solid fuel-fired furnaces Fuel in direct contact Recuperative Manual and Batch, periodic Natural/self, Crucible, shaft Melting roasting Shaft, muffle... 

Finely divided combustible solids, if intimately mixed with air, can explode. Several disastrous explosions have occurred in grain silos. 

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