Methane hazard

Figure 8.4 Performance assessment criteria of ventilation layer for methane hazard (DETR, 1997)...

When we consider sources of methane we have to add old methane methane that was formed millions of years ago but became trapped beneath the earth s surface to the new methane just de scribed Firedamp an explosion hazard to miners oc curs in layers of coal and is mostly methane Petroleum deposits formed by microbial decomposi tion of plant material under anaerobic conditions are always accompanied by pockets of natural gas which IS mostly methane... 

Grade C, Type II is typical of Hquid oxygen used as a rocket propellant oxidizer. Particulate content is limited because of the critical clearances found in mechanical parts of the rocket engine. In addition to water, acetylene and methane are limited because, on long standing, oxygen evaporation could cause concentration of these combustible contaminants to reach hazardous levels. 

The main hazard is that of flammability. The following precautions supplement those in Table 9.3 for the storage of methane gas cylinders ... 

Landfill disposal of certain categories of solid waste may result in gas generation, mainly methane, and a highly polluted leachate. The methane may be drawn off, to avoid a flammable hazard on- or off-site. The leachate is pumped off for treatment. 

Group D. Atmospheres such as acetone, ammonia, benzene, butane, cyclopropane, ethanol, gasoline, hexane, methanol, methane, natural gas, naphtha, propane, or gases or vapors of equivalent hazard. 

Mesitylene [Benzene, 1,3,5-tnmethyl-], 86 Z Met Gly Gly OEt [Gly cine,V-[Ar-[A-[(phenylmethoxy)carbonyl] -L-methionyl] glycyl] -, ethyl ester], 9 3 Methane, iodo-, hazard note 127 Methyl chlonde polystyrene [Benzene, diethenyl-, polymer with ethenyl-benzene, chloromcthylatcd], 96 Methyl iodide [Methane, iodo-], 79 Methyl mercaptan [Methanethiol], 73 Moffat oxidation, 99... 

Methane, bromo, 55, 63 Methane, (4 tert butylphenyl) phenyl [Methane, 4-(l,l-dimethylethyl)-phenyl-phenyl-], 55, 11 Methane, iodo-, 55, 3 Methane, iodo-, hazard note, 55, 134 Methane, (4-isopropylphenyl)-phenyl- [Methane, (4-(l-methylethyl)phenyl)-phen-yl-1,55, 11... 

Gas may be formed by microbiological degradation of organics, evaporation and volatilization of volatile materials, or chemical reactions. The high combustibility of methane—a major component of landfill-generated gas—is a potential hazard. The emission of gas can be accelerated by elevated temperatures and venting conditions. Air pollution, which may result from gaseous... 

Anaerobic processes that produce methane from waste solve 2 problems at once waste and energy. Anaerobic processes provide some of the simplest and most practical methods for minimizing public health hazards from human and animal wastes. Pathogens such as schistosome eggs, hookworm, flat/tape worm, dysentery Bacillus, poliovirus, Salmonella, and... 

Break Test II uses a gas mixture of 3-60% propane with air and nitrogen, which is more easily ignited than methane/air. Preliminary shots determine the most hazardous charge of explosive not exceeding 227 g. Twenty-six shots are then fired at this weight and not more than thirteen ignitions may occur. 

The method of mining is somewhat like driving two sets of tunnels at right angles through the strata. Most mines of this type do not present any hazard from methane and therefore non-permitted explosives can be used. The selection of powder or gelatine type of explosive depends on the nature of the rock and particularly on the wetness of the mine. 

Suggestions of untoward hazard inherent in the preparation of nitrosotrifluoro-methane by pyrolysis of trifluoroacetyl nitrite [1] are discounted in the later reference, which gives full details of the equipment and procedure that had been used uneventfully during the previous decade [2],... 

CHETAH calculations for energy/hazard of an hypothetical decomposition reaction to carbon, water and methane are reported [14],... 

The explosive properties of liquid methane-oxygen mixtures were determined [8], Dining investigation of an explosion in a portable air liquefaction-separation plant, hydrocarbon oil was found in a silica filtration bed [9], The mechanism of slow heterogeneous accumulation of hydrocarbons dissolved in trace amounts in liquid oxygen on the liquid evaporator surfaces is discussed. It was concluded that months of continuous evaporation would be required to attain explosion-hazardous levels in real evaporators [10],... 

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