Contact with atmospheric fluidized bed adsorption
     1976 , GibeM proposed to freeze the material immersed in a fluidized adsorbent for low temperature drying . Fluidized adsorbent particles in water adsorption heat is emitted , substantially the required heat of sublimation drying rather , eliminating the need for external heating . The research group of starch gel as adsorbent of the adsorption pressure of the bed of potato block freeze- dried, and vacuum freeze drying are compared. Experimental results show that the quality of the product does not substantially change ( in a fluidized bed drying , the potato is the corner wear and adhesion trace on the adsorbent ) , the drying time. In the drying time , the thickness of the material constraints . However , the adsorption pressure and freeze-dried in energy operating costs ( simple ) has advantages , can save 30 % or more . It should be noted that this is a difficult point drying method from the adsorbent bed is completely separate product , so the development of products compliant with the adsorbent is an important future research topic.
    In addition , Lombrana and vmaran cold Chen discusses adsorption pressure changes during the drying process the drying speed. They propose a suitable pressure / temperature alternate drying process , ① the atmospheric pressure , -10 ℃; ② vacuum ,0-15 ℃; ② pressure , <15 ℃). The freeze- drying process can reduce the adsorption drying time up to 50% . From the figure, the temperature / pressure changes in cross- moss drying mode , the drying process , and there is constant deceleration phase, while under -10 ℃ conventional freeze-drying is not constant phase.