A liquid nitrogen spray freeze granulation vacuum drying device and working method

Abstract

The invention discloses a liquid nitrogen spray frozen granulation vacuum drying device and a working method. The device solves the problem that in the biotechnology field, when liquid materials are frozen and dried directly, due to the fact that the water sublimation surface is small and air current channels among particles are not smooth, the speed is low, and the efficiency is low. The device sprays the liquid materials into continuously sprayed ultralow-temperature liquid nitrogen mist through nitrogen pressure, material liquid drops are rapidly frozen to be amorphous spherical particles, the amorphous particles are in a non-balanced high-energy state, and drying is easy. Particle materials made through co-spray are stacked on screens which can be folded in a spray chamber and have a heating function, and the larger sublimation surface of the particle materials and through moisture migration and overflowing channels formed by particle voids and the porous screens are beneficial for rapid drying of the materials. In addition, when co-spray granulation is conducted, low-temperature nitrogen flow flows through made material particles and condenser pipes from top to bottom, and the material particles can keep low temperature and fully utilize residual cool.

Description

technical field [0001] The invention relates to a spray vacuum freeze-drying device. After the solution is sprayed and liquid nitrogen quick-frozen and granulated, dry powder is obtained by vacuum freeze-drying, which belongs to the field of bioengineering. [0002] technical background [0003] Particle size reflects the size of solid particles, and there is an inverse correlation between particle size and specific surface area, and the finer the particle size, the larger the specific surface area. In a chemical reaction, the particle size affects the reactivity and speed of the reactant through the specific surface area, so the solid reactant usually needs to reduce the particle size before the chemical reaction. Reducing the particle size is also used in other aspects, such as vacuum freeze-drying. Ice particles with a certain particle size can balance heat transfer, air permeability and sublimation area during the vacuum freeze-drying process, thereby increasing the dryin...

AI Technical Summary

Problems solved by technology

However, the above methods have common shortcomings, that is, the uniformity of the formed ice particles is limited. Whether it is sprayed in a countercurrent or sprayed into the refrigerant, the ice particles are deformed to varying degrees, and the size distribution is uneven, and the speed of forming solid particles is slow.

As a result, the low-temperature spray granulation technology has not been applied industrially

Images