What Is Spray Drying Process?
What is spray drying process? For people who have bought a spray dryer machine, it is of great importance to know the operation process of spray dryer. Hawachdryer decomposes the process into three steps for you to better understand. Come and see them now!
Operation process of spray dryer — preheating
Turn on the centrifugal fan firstly, and then turn on the electric heating. Check if there is any air leakage inside the spray dryer preheating barrel. If normal, the barrel can be preheated. Since the hot air preheating determines the evaporation capacity of the drying equipment, the inlet air temperature should be increased as much as possible under the premise that the quality of the dried materials is ensured. During preheating, the valve at the bottom of the drying chamber and the discharge port of the cyclone must be closed to prevent cold air from entering the drying chamber and reducing the preheating efficiency.
Operation process of spray dryer — feeding and drying
When the inlet temperature of the drying chamber reaches 180℃~220℃, turn on the centrifugal nozzle. When the nozzle reaches the maximum speed, turn on the feed pump on the spray dryer and add the material liquid. During the spray drying process, the feed volume should be from small to large, otherwise, it will cause a wall sticking phenomenon. The concentration of the material liquid should be prepared according to the temperature and nature of the material to ensure that the finished product has good fluidity.
During the operation process of spray dryer, it is extremely important to ensure that the exhaust air temperature(outlet temperature) is constant. This depends on the size of the feed volume. Ensure regulated and stable feed volume, and the exhaust air temperature will not change. If the solid content and flow rate of the material liquid change, the temperature will also change. If the product temperature is too low, reduce the amount of feed to increase the outlet temperature. If the temperature of the product is too high, do the opposite. For heat-sensitive materials with lower product temperature, the amount of material can be increased to reduce the exhaust temperature, but the humidity of the product will increase accordingly;
Operation process of spray dryer — product collecting
The finished product after drying is collected in the pollinator at the lower part of the tower and the cyclone separator. The pollinator should be replaced before it is full. When replacing the pollinator, the butterfly valve above must be closed. If the dried product is hygroscopic, the cyclone separator and its pipes, and the pollinator should be wrapped with insulation material to avoid moisture absorption of the dried product.
What is spray drying process? After reading this article, you shall know what to do with your spray dryer. Remember the things that require your attention during the spray drying process, and you will avoid a lot of trouble. Except for the comparably bigger centrifugal spray dryer we mentioned in the operation steps, we also have small spray dryer to meet your needs. Enquire now!