Spray drying equipment drying technology is to use a spray method to disperse the material in a hot air stream in a mist state. The material is in full contact with the hot gas to complete the heat transfer and mass transfer process in an instant, so that the solvent is quickly evaporated into a gas to achieve drying. the goal of. Spray drying technology is widely used in the pharmaceutical industry. In the field of solid preparations, it is often used for the drying of easily decomposable drugs in high heat sensitive medicines and liquid concentrates. The obtained product has fine particle size, uniformity, good fluidity and fast solubility.
The spray drying device is a drying device for directly drying a solution or a suspension into solid particles, which can save unit operations such as evaporation, crystallization, separation and pulverization, and can be continuously and automatically produced, and the operation is stable. By adopting the drying method, the gas-solid two-phase contact surface area in the spray drying device is large, and the drying time is short, generally 5 to 30 s, which is suitable for drying the heat sensitive material. The product obtained by drying has good performance, and particles of 30 to 50 mm can be obtained, and the product has good fluidity and fast solubility. The disadvantage is that the dryer has a large volume and a low heat transfer coefficient, resulting in low thermal efficiency and high power consumption.
There are many classification methods for spray drying equipment. According to the flow direction of gas and liquid, it can be divided into parallel flow, counter flow and mixed flow; according to the installation method of atomizer, it can be divided into upper spray type and lower spray type; The structure can be divided into centrifugal type, pressure type and air flow type; according to whether the heating gas is circulated, it can be divided into open type, partial circulation type and closed type.