Dehydration of air

Gas Dehydration Water is extremely permeable in polymer membranes. Dehydration of air and other gases is a growing membrane application. 

Thermal decomposition (dehydration) of air-dried X-ray amorphous CPH proceeds in different ways. Similar to the decomposition of X-ray amorphous hydroxides, it occurs gradually at a wide temperature range, while the total mass loss at isothermal dehydration gradually increases at elevated temperatures. 

Dehydration of Air. Asaeda et al. [19S4] evaluated gamma-alumina membranes on kaolin supports with a reported pore diameter of about 1 nm for air dehydration under a temperature of 31 to 7VC and a low TMP of 0.04 to 0.39 bar. A separation factor of 7 to 460 was obtained. The corresponding permeance is about 9.9x10 cm (STP)/s-cm -cmHg. 

Other membrane-based gas-separation applications that developed in the late 1980s and the 1990s include the separation of carbon dioxide from natural gas, separation of organic vapors from air and nitrogen, and dehydration of air. Table 7.3 lists the major companies involved in the industry and their principal markets. Currently, total industry sales are estimated to be about US 200 million. Of all the industrial membrane-separation processes, gas separation is... 

Silica gel. This is a hard, granular, very porous product made from the gel precipitated by acid treatment of sodium silicate solution. Its moisture content before use varies from roughly 4 to 7 percent, and it is used principally for dehydration of air and other gases, in gas masks, and for fractionation of hydrocarbons. It is revivified for reuse by evapoiatitm of the adsorbed matt. ... 

In the dehydration of air at atmospheric pressure for air conditioning, the pressure drop through the desiccant must be kept to an absolute minimum, and very shallow beds are... 

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