Spontaneous combustion liability

Spontaneous Combustion Liability of Subbituminous Coals Development of a Simplified Test Method for Field Lab/Mine Applications... 

The spontaneous combustion liability S-index was determined for the eighteen coal samples using the following equation ... 

The modified nonadiabatic method described for the determination of the spontaneous combustion liability of subbituminous coals can yield satisfactory results. However, a more realistic measurement of a coal s self-heating tendency might be obtained through the use of an adiabatic system. In this case, heat derived from the coal oxidation would not be transferred to the surroundings. A spontaneous combustion instrument intended for field or lab/mine applications should be less complex, yet it should be capable of producing data that is reasonably accurate for predicting the self-heating characteristics of coals. 

V, Testing Firework Mixtures for Liability to Spontaneous Combustion... 

A different consequence of coal oxidation is the development of spontaneous combustion (Chapters 9 and 14), when the heat generated by in situ oxidation canses the coal to smolder and nltimately bnrn without any external heat source. The liability to oxidation is mainly determined by the coal s rank, in conjunction perhaps with the maceral content (Chapter 4) and the content of mineral matter (Chapter 7). Low-rank coal is particularly prone to spontaneous combustion and factors, snch as access of air to coal stockpiles, may need to be controlled to reduce the ever-present risk of spontaneous ignition and combustion. 

Almost all types of coal may ignite spontaneously in snitable environmental conditions. This leads to serions safety problems as well as economic losses for coal mines and storage areas. The determination of the liability of a coal type to spontaneous combustion is qnite important in dealing with the problem before, during, and after mining. 

Spontaneous combustion is usually the culmination of several separate chemical events and although precise knowledge of the phenomenon is still somewhat incomplete but is gradually becoming known, there are means by which the liability of a coal to spontaneously ignite can be tested and evaluated (Brooks et al., 1988). 

Films, Nitrocellulose Base. A type of film which consists mainly of nitrocellulose. As such the material has a low ignition temperature and bums rapidly when ignited, evolving gases which are toxic. When new and in good condition the film is reasonably stable and free from liability to spontaneous heating and combustion. Film that has deteriorated badly becomes very unstable and may be liable to spontaneous heating unless kept under water. ICAO A2... 

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