The New Drying Method : Spray Dryer
The device is a set that can finish drying and prilling at one time, which is different from common dryer device, such as rotary dryer . According to process requirements, plant can get a proportion of ball particles by adjusting the size of pressure, flow and orifice.
The working process: Feed liquid is sent into device through diaphragm pump high pressure, and spray fog droplets, then fall down with hot wind, most particles are collected at the discharge gate of tower. Waste gas and tuny powder is separated by cyclone separator, and waste gas is discharged by exhaust fan, powder is collected by Pollination barrel set at the bottom of cyclone separator.
Performance and Features
High drying speed, feed liquid’s surface increased largely through pulverizing, in hot airflow, 95%－98% water will evaporate instantly, the time of finishing drying is about ten seconds or less, especially adapt to the drying of heat saisitive mataials. All products are ball particles with equable granularity, good liquidity, good Solubility, high purity and high quality. According to the characteristics of raw material, it can use hot air to dry and can also use cool air to granulate. In addition, it is easy operation, convenient control and easy to realize automated operation.
The requirements of spray dryer for equipment
1.The parts that touch with product should be convenient to clean;
2.Plants should have measures to prevent coke powder, and avoid hot air generate whirlpool and countercurrent;
3. preventing air from bringing impurity into products;
4. Configuring the device of temperature and pressure indicator recorder;
5. Owning dust recovery unit with high efficiency;
6. Cooling powder quickly to improve solubility and instant ability;
7. The indoor temperature and air exhaust temperature should be less than 100 degrees for the safty and quality;
8. Thick liquid cream drip evenly touch with hot air for high hot efficiency;
9. For the viscous materials, reducing wall sticking phenomenon.
The advantages of spray dryer
1. The drying process is very rapid;
2. Materials can be directly dried into powder;
3. It is easy to change drying conditions and adjust product quality standard;
4 .Because of sudden evaporation, the selection of device materials is not strict
5. The negative pressure in dryer room guarantees the sanitary condition in production and avoid the dust rise in workshop, and further improve the product purity;
6.High production efficiency and fewer operators.
The disadvantages of spray drying
1. The device is more complicated and occupying large lands, big one-time investment;
2. Atomizer and Powder recovery unit with high price;
3. It needs much air, and increasing power consumption of air blower and capacity of recycle device is necessary;
4. Low hot efficiency and more hot consumption.