Pressurized gases

In the spht- or dual-pressure process, low to medium pressure gases (ca 0.3—0.6 MPa) containing nitrogen oxides are compressed to ca 1.1—1.5 MPa for efficient absorption in water to make nitric acid. Stainless steel is used for constmction in this corrosive environment and, because of the potential for... 

Low-temperatiire liquefied gases are shipped in special ships with insulation between the niiU ana an inner tank. Poisonous materials are shipped in separate tanks built into the ship. This prevents tank leakage from contaminating harbors. Separate tanks are also used to transport pressurized gases. 

General ventilation provisions, particularly if volatile toxic or highly flammable liquids, or toxic or flammable pressurized gases are stored. 

In many cases, pressurized gases in vessels do not behave as ideal gases. At very high pressures, van der Waals forces become important, that is, intermolecular forces and finite molecule size influence the gas behavior. Another nonideal situation is that in which, following the rupture of a vessel containing both gas and liquid, the liquid flashes. 

Wiederman, A. H. 1986a. Air-blast and fragment environments produced by the bursting of vessels filled with very high pressure gases. In Advances in Impact, Blast Ballistics, and Dynamic Analysis of Structures. ASME PVP. 106. New York ASME. 

Low-temperature, high-pressure gases at moderate to low temperatures can be expanded by the use of an expansion turbine (very similar to a steam turbine or even by reciprocating or screw-type compressors) or by the use of a throt-... 

Following tests made with this equipment, publications show values for Q and related coefficients for many high-pressure gases and polymers indicating (cf. Section 23.5.1.4) how... 

Following this, elastomers can be swollen by some high-pressure gases (especially CO2) as the densities of these gases approach liquid-like levels, at appropriate temperatures they become supercritical fluids which possess a solubility parameter magnitudes that, however, are highly dependent on temperature and pressure... 

Heat exchangers for liquids normally have a pressure drop in the range 0.35 to 0.7 bar (see Chapter 15). For gases, heat exchangers have a pressure drop typically between 1 bar for high-pressure gases (10 bar and above), down to 0.01 bar for gases under vacuum conditions (see Chapter 15). 

Heat and Mass Transfer in Low Pressure Gases Applications to Freeze Drying... 

At very high pressure, where the mean free path is short compared to the separation distance between surfaces, (a A jX)dP 1, and Eq. (101) reduces to the heat flow equation for moderate pressure gases given by Eq. (88). Although the derivation given here is not self-consistent when the mean free path is roughly the same as the separation distance, it is interesting to note that as the pressure becomes very small, (a A0/X)dP 1, and Eq. (101) reduces to the free molecular... 

A mass spectrometer is often indispensable for a complete analysis of low-pressure gases, but a description of the various types of spectrometers is beyond the purpose of this book, but see, for example, ref. [18]. We simply remind that a mass spectrometer consists of three parts an ion source where the neutral gas is ionized (usually by electron bombardment) an analyser where ions are selected according to their mass to charge ratio and a collector with an amplifier to measure the weak ion current. 

VCEs have increased in number because of an increase in inventories of flammable materials in process plants and because of operations at more severe conditions. Any process containing quantities of liquefied gases, volatile superheated liquid, or high-pressure gases is considered a good candidate for a VCE. 

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