Activated alumina desiccant is a spherical activated alumina made by special process. Its own properties are non-toxic, odorless, non-pulverizing, insoluble in water, white spherical in appearance and strong in water adsorption. Under certain operating conditions and regeneration conditions, its drying depth is as high as the dew point temperature below -70℃, which is manly used for drying of liquids and gases.