The spray dryer is a kind of equipment that can complete its drying and granulation together during operation. The whole equipment belongs to the hot air direct connected drying equipment. During operation, the materials will be effectively atomized into droplets through its atomizer, which will be directly sprayed into the tower during operation. It is loose and mysterious in the hot air flow, and the drying of wet materials will be completed during the acceleration and transportation in the air flow. It is applicable to solutions and suspensions, A paste or colloidal material.

At present, there are three types of atomizers for spray dryer to complete material atomization:

1. pressure spray (pressure nozzle)

The high-pressure pump (70-200 atmospheric pressure) is used to force the liquid to pass through the small hole (the hole diameter is 0.5-1.5um) to loosen it into droplets;

2. use high-speed activities of compressed air or superheated steam (generally 2.5-6 barometer pressure) to loosen the solution into droplets;

3. centrifugal chamber spray

The high-speed rotating disc (75-150m/s circumferential speed) is used to loosen the liquid into droplets under the action of centrifugal force.

Operating principle of spray dryer

During the operation of the spray dryer, its air will be effectively heated through it, so it will directly enter the top air distributor of the dryer, and its hot air will enter the monotonic chamber in a spiral shape to a certain extent. The feed liquid passes through the high-speed centrifugal atomizer at the top of the tower, spray into very fine mist liquid beads, which can be dried into products in a very short time in parallel contact with hot air. The products are successively output from the bottom of the drying tower and the cyclone separator, and the waste gas is discharged by the induced draft fan.

In the process of using the centrifugal spray dryer, the unloading time of the tower body is long, so the strength of the materials used in the tower body planning is high. Because the machine needs to continuously input high hardness materials during operation, the tower body will be greatly worn, and then the tower body will be cracked. When the closed centrifugal spray dryer is used, the impact of the fabric is very large. Therefore, in the planning process, the material is required to have high wear resistance and strength.

The spray dryer should be used together to reduce its wear rate, reduce and eliminate abnormal wear. It is necessary to use the equipment reasonably and do a good job of protection and maintenance in time.