Hydrogen explosions from

In order to be 100% safe from a hydrogen explosion (sources passivation air, CO2), a hydrogen removal system is installed before the CO2 passivation air enters the stripper. 

Fig. 20-4 Safety precautions for water tanks (a) and filter tanks (b) to prevent danger of explosion from hydrogen.

Cathodic protection of water power turbines is characterized by wide variations in protection current requirements. This is due to the operating conditions (flow velocity, water level) and in the case of the Werra River, the salt content. For this reason potential-controlled rectifiers must be used. This is also necessary to avoid overprotection and thereby damage to the coating (see Sections 5.2.1.4 and 5.2.1.5 as well as Refs. 4 and 5). Safety measures must be addressed for the reasons stated in Section 20.1.5. Notices were fixed to the turbine and the external access to the box headers which warned of the danger of explosion from hydrogen and included the regulations for the avoidance of accidents (see Ref. 4). 

Other factors that determine the catastrophic effects of an explosion are the initial density of the explosive (which is more than three orders of magnitude higher for TNT than for hydrogen-air mixture) and detonation velocity (which is three to five times higher in TNT). Therefore, the resulting pressure wave from a hydrogen explosion is considerably flatter (longer duration and lower maximum overpressure) than TNT, and destruction effects are mainly caused by impulse rather than overpressure. 

White phosphorus ignites in contact with boiling sulfuric acid or its vapour [1]. An explosion hazard exists at industrial scale under milder conditions [2], Even red phosphorus reacts vigorously with sulfuric acid in the presence of iodine or iodides, to produce hydrogen sulfide, from about 80°C [3],... 

The third reaction takes place in a reactive distillation tower where the iodhiric acid is concentrated and decomposed simultaneously, to produce hydrogen at a temperature range from 200 to 310°C and pressure up to 22 bar (Brown, 2003). This section requires analysis of iodhidric acid leak and hydrogen explosions, though these sections are not covered in this paper as they will be the subject of future developments. 

It can be seen in these figures that the fragment ions tend to be ejected more isotropically as the hydrogen migration from the terminal carbon to the nitrile group proceeds. The extent of the anisotropy in the explosion pathways can be evaluated quantitatively from the expectation value of the squared cosine, (cos2 9) = f 1(9) cos2 9 sin 9d9/ f 1(9) sin 9d9. For the n = 0 pathway... 

The sharp maxima observed on some extraction curves (e.g. the peaks 1 and 2 in Fig. 12.) correspond to explosive character of hydrogen emission from the traps-defects. 

The risk to the public during consumer end use of hydrogen derives from the possibility of accidental fire and explosion, a direct consequence of the physical and chemical properties of hydrogen. These properties help to define the kinds of safety issues that must be addressed, the fundamental design goals for hydrogen systems, and the operational limitations of these systems. Table 9-1 summarizes the properties of hydrogen in contrast with those of other commonly used fuels. 

MacDiarinid, J. A. and G. J. T. North, Lessons Learned from a Hydrogen Explosion in a Process Unit," Plant/Operations Progress, April 1989 pp. 96-99. 

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