Air separation cryogenic

Cryogen-free electromagnets, 23 856 Cryogenic adsorption processes, 73 461 Cryogenic air separation, 77 275-278, 752-753... 

ATR is used widely, although costs are relatively high due to the high capital and energy costs related to the cryogenic air separation plant (approx. 40% of the total capital costs). For large-scale plants, however, such as gas-to-liquid plants, but also possibly natural gas based power stations with pre-combustion C02 capture, ATR becomes more economic than SMR [7]. 

Figure 9.2 Sensitivity of investment cost to membrane price and 02 flux in autothermal reforming, after [14]. Cost employing conventional cryogenic air separation technology shown by broken line.

Argon, neon, krypton, and xenon are all produced commercially as byproducts from large cryogenic air separation plants. The distillation of liquid air is normally performed in the double-column arrangement (Fig. 1). The rare gases are produced in side columns operated in conjunction with the standard double-column plant. 

Depending on volume and purity requirements, nitrogen can be supplied by several different production systems or delivery systems. Figure 1.1 illustrates some of these systems159. Liquid refers to delivery by trucks or in cylinders Permeation refers to a membrane system Adsorption refers to a PSA system and Distillation refers to a cryogenic air separation plant. 

A flowsheet for a plant that produces nitrogen in a cryogenic air separation plant is shown in Figure 1.2150. 

The cryogenic air separation process starts with air entering the plant through air filters, where it is compressed and cooled. The air is passed through heat exchangers for further cooling and for removal of water vapor and carbon dioxide by freezing. Solid adsorbents, such as molecular sieves, silicas, and aluminas can also be used to remove the water and carbon dioxide by adsorption before separation of... 

Nitrogen usually is produced by cryogenic air separation, liquefaction of atmospheric air, and removal of the nitrogen by distillation, as described earlier. Noncryogenic adsorption technology, including PSA and VSA systems, economically provides nitrogen for requirements between 4,000 and 30,000 standard cubic feet per hour (SCFH).9... 

CGA P-8 Safe Practices Guide for Cryogenic Air Separation Plants... 

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