Cryogenic fluids, spills

Commercial monitors and alarms are now available to detect the vapors of each of the cryogenic fluids considered here (Chapter 5). Unfortunately, many of these respond too slowly for effective use under gross spill conditions in practice, operating personnel can often detect a hazardous condition before the alarm sounds. There have been... 

Supercritical Fluid Extraction. The properties of cryogenic fluids under supercritical conditions give them considerable potential for regenerating spent adsorbents. The solution characteristics of the fluid should be compatible with the adsorbed components and, when the fluid is pumped through the adsorbent bed, it will dissolve the adsorbed spiU components. The supercritical fluid can be evaporated easily due to its volatility, and in some cases both the solvent and the contaminant from the spill can be recovered. The high solvation character of the supercritical fluids is due to low intermolecular distances between the solvent molecules. This novel process is expensive at present and therefore the spilled material should be high value added and recoverable, such as pharmaceutical products. 

Thermal burns result from the radiant heat emitted by a hydrogen fire and absorbed by a person, which is directly proportional to many factors including exposure time, burning rate, heat of combustion, size of the burning surface, and atmospheric conditions (mainly wind and humidity). For instance, thermal radiation flux exposure level of 0.95 W/cm2 may cause skin burns in 30 s. Cryogenic burns may result from contact with cold fluids or cold vessel surfaces. Exposure to large liquefied hydrogen spills could result in hypothermia, if proper precautions are not taken [17]. 

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