HANNOVER MESSE 2019,
01 - 05 April
The compression of humid ambient air, for example in an industrial application, produces liquid water by condensation. If the application does not allow moisture for chemical-physical reasons or danger arises due to the precipitation of the moisture, the air must be dried before compression.
The maximum water vapor content of a compressed air volume unit is caused by the temperature of the compressed
air and is almost completely independent of ist pressure. The water vapor content is therefore theoretically represented by the dew point, which indicates the temperature at which the actual water vapor quantity corresponds to a relative humidity of 100 % and below which condensation begins.
Drying in this context means a reduction of the dew point below the actual operating temperature. For drying to lowest dew points, essentially only the process of adsorption, in which water is bound to a solid phase, is suitable.
Adsorption is thereby defined as the attraction of a substance (the adsorbate) to the surface of a solid body (the adsorbent) via physical binding forces. Desorption, on the other hand, refers to the release of the adsorbate from the adsorbent. Since the adsorption capacity of adsorbents decreases with increasing temperature and decreasing pressure, moisture can be desorbed again by heat supply or pressure reduction.
The adsorbents used in such a drying process are hightech desiccants and have an inner surface area of up to 1000 m2/g, due to their pore structure of macro-, meso- and micropores, where condensed water vapor can accumulate. For the drying of compressed air, silica gels, aluminum oxides (activated alumina) and zeolitic molec-ular sieves are most commonly used. These desiccants reach dynamic adsorption capacities above 20 % by weight and dew points down to -100 °C.
BASF Sorbead®Air R is a high performance adsorbent for dehydration of air, technical gases and liquids. The patented BASF Sorbead® Air line of highly efficient adsorbents ...
BASF Sorbead® Air WS water-resistant silica gel adsorbents have high capacity and protect other adsorbents and catalysts from water and moisture in a broad range ...
BASF F-200 is a smooth sphere of activated alumina produced by BASF’s unique manufacturing process. F-200 is an excellent adsorbent for drying a wide variety of ...
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