Application of steam heating method to freeze drying

The invention relates to application of a convectional heat transfer mode to the material freeze drying process. An application method is mainly characterized in that in the traditional freeze drying process, when solid water (or other solvents) starts to vaporize, a proper amount of steam is led to give steam latent heat to the solid water, so that the solid water is sublimated to vapor in an accelerated mode; and meanwhile, by utilizing kinetic energy which is released when the steam expands instantly, the vapor gets rid of the restraint of surface tension and quickly flees from the surfaces of materials to be discharged out of a freeze drying cavity, and therefore the purposes of achieving complete freeze drying and shortening the drying time are achieved. 本发明涉及种对流传热方式在物料冷冻干燥过程中的应用。该方法的主要特征是在传统的冷冻干燥过程中当固态水(或其他溶媒)开始汽化时，通入适量的水蒸汽，使固态水获得蒸汽潜热而加速升华为水气；同时，水气借助蒸汽瞬间膨胀而释放出的动能，挣脱表面张力的束缚迅速逃离物料表面、排出冻干腔体，从而达到完全冻干以及缩短干燥时间的目的。