Methane fires

Rouson, D., S.R. Tieszen, and G. Evans, Modeling convection heat transfer and turbulence with fire applications A high temperature vertical plate and a methane fire, in Proceedings of the Summer Program. 2002, Center for Turbulence Research, Stanford University, pp. 53-70. 

The atmosphere of coal mines frequently contains enough methane (fire damp) to make it explode from the flame of a black powder or dynamite blast. Dust also produces an explosive atmosphere, and it may happen, if dust is not already present,... 

CH4, methane, fire damp 248 Chakatsuyaku = TNT (Japan) 339 chaleur de combustion = heat of combustion 161... 

Hydrogen sulfide release resulted in eight deaths and 29 injuries Methane fire resulted in 52 deaths... 

Yellow hexagonal crystals or powder, mp 2100" decomposes above 2200°, d 2,36. Decomposed by water with evolution of methane (fire hazard). 

If a methane fire should occur, shut off the gas source if this can be done without risk. If the source cannot be shut off, let the fire bum itself out while making sure that gas storage receptacles and piping containing gas in close proximity, as well as combustible materials in the area, are kept cool by spraying with water. The local fire department should be called. 

Heat is also needed to evaporate the feed water. It is useful to use the waste heat of the cell for these purposes. A general model of a methane fired combined SOFC cycle based on the reference cycle of Figure 3.9 is shown in Figure 3.11 to describe the thermodynamic influences on the system s behaviour as simply as possible [2.7.8]. 

There are, however, a variety of other sources of methane that have been considered for fuel supply. Eor example, methane present in coal (qv) deposits and formed during mining operations can form explosive mixtures known as fire damp. In Western Europe, some methane has been recovered by suction from bore holes drilled in coal beds and the U.S. Bureau of Mines has tested the economic practicaUty of such a system. Removal of methane prior to mining the coal would reduce explosion ha2ards associated with coal removal. As much as 11.3 x 10 (400 trillion (10 ) cubic feet or 400 TCE) of... 

Various bromofluoromethanes have been described and proposed for use as fire extinguishing agents (qv). Two that have been recommended highly for this purpose are dibromo difluoromethane [75-61-6] CBr2p2, and bromotrifluoromethane [75-65-8], CBrF, (94). Bromochlorodifluoromethane [353-59-3], CBrClF2, is another fire extinguishing agent. These and similar substituted methanes are potentially useful for the synthesis of other halo—fluoro compounds. 

Combustible gas detection systems are frequently used in areas of poor ventilation. By the early detection of combustible gas releases before ignitible concentration levels occur, corrective procedures such as shutting down equipment, deactivating electrical circuits and activating ventilation fans can be implemented prior to fire or explosion. Combustible gas detectors are also used to substantiate adequate ventilation. Most combustible gas detection systems, although responsive to a wide range of combustible gases and vapors, are normally calibrated specifically to indicate concentrations of methane since most natural gas is comprised primarily of methane. 

When a plant was taken out of use, the cooling water lines were left full of water. Dismantling started nearly 20 years later. When a mechanic cut a cooling water line open with a torch, there was a small fire. Bacteria had degraded impurities in the water, forming hydrogen and methane [20]. 

ESCA has been used to determine the molecular structure of the fluoride lon-induced tnmenzation product of perfluorocyclobutene [74] and the products of the sodium borohydnde reduction of perfluoromdene [75] ESCA is also used to analyze and optimize gas-phase reactions, such as the bromination of trifluoro-methane to produce bromotrifluoromethane, a valuable fire suppression agent [76] The ionization energies for several hundred fluorme-containing compounds are summarized in a recent review [77]... 

The unique combination of properties associated with certain fluonnated methanes and ethanes has led to their widespread use in fire suppression systems The three halogenated fire suppression agents in general use today are bromo-trifluoromethane (CF Br, Halon 1301), bromochlorodifluoromethane (CF2BtCl, Halon 1211) and, in small volumes, primarily in the republics of the former Soviet Union and Eastern European nations, 1,2-dibromotetrafluoroethane (BrCF2Cp2Br, Halon 2402)... 

For methane-air fireballs, Hardee et al. (1978) found an of 469 kW/m. If an extinction coefficient of k = 0.18 m (as measured in LNG fires) is used, the curve shown in Figure 6.8 can be obtained from the equations given by Hardee et al. (1978). Equation (6.2.3) overstates emissivity as determined through experiments. Possible explanations are... 

Phenothiophosphine ring-containing polyamides and polyesters were also prepared by the polycondensation of 2,8-bischloroformyl-lO-phenylphenothiophos-phine 5,5, 10-trioxide with aromatic diamines such as 4,4 -diaminodiphenyl ether and 4,4 -diaminodiphenyl-methane, and bisphenols such as 4,4 -dihydroxybiphe-nyl and 4,4 -dihydroxydiphenylmethane, respectively [159]. These polymers are soluble in polar aprotic solvents and also exhibit good heat and fire resistance. Phosphorus containing high performance polymers are shown in Table 6. 

Figure 7-63A. Venting nomograph for methane. Reprinteed with permission, NFPA 68-1988, Deflagration Venting, (1988) National Fire Protection Association, Quincy, MA 02269. Note This materiai is not the complete and official position of the National Fire Protection Association on the referenced subject, which is represented only by the standard in its entirety. Note from this author this statement applies to all material referenced for use that originates with the National Fire Protection Association [27].

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