The method of dye granulation.

1. Wet granulation.

The dye filter cake, additives and adhesives were added to the mixer for full mixing, and then the extruding granulator was extruded, and the extruded length was 0.5-2mm cylindrical particles through a screen with a diameter of about 1mm. Cylindrical particles obtained from low temperature drying, and then, this method is suitable for the active dyes such as water-soluble dye granulation, joining in the formulation of adhesive are mainly sodium alginate and carboxymethyl cellulose, hydroxypropyl cellulose, sucrose, sodium acrylate and polyvinylpyrrolidone water-soluble polymer compounds. The dosage of the adhesive should not be too much, the general dosage is about 1%~5% of the dye amount.

2. High frequency granulation.

High frequency inside the material into the granulator granulation is, pelleting machine is equipped with the paddle at the bottom of the stirring, the pelleting machine can produce high-frequency oscillation of stirring devices are installed side wall, the bottom spewing adhesive to the powder material. After mixing, the adhesive is combined with the dye, and the stirring device on the side wall will strengthen the granule. The particle size can be changed by changing the shape of the mixing device and the frequency of the vibration.

Three, melt granulation.

To dye with the additive mix, commonly used additives is melting point in 50 ~ 200 ℃ water soluble compounds such as urea, sugar, and polyols, the formation of the melt. When the solution is formed, it is sent to a device that can be dispersed into droplets, such as a porous high-speed rotating centrifugal nozzle, which is cooled and formed. The particles obtained by this method are solid particles with considerable mechanical strength, and the damage rate of the particles is small.

4. Dry granulation.

Dry granulation is adopting fluidization technology, will dry powder spray dye in the fluidized bed, appearing through the nozzle to the fluidized bed spray adhesive, a fluidized state of powder dyes with good contact with the adhesive's droplets are bonded together, after freeze-dried form particles, this method can continuous production, has shaped dry granulation equipment abroad.

5. Spray granulation.

Spray granulation is a lot of dye factory wide application of a kind of granulation methods, spray zha li is dye in dry granules at the same time, especially suitable for heat-sensitive, low viscosity dye dry granulation. According to the equipment, spray granulation can be divided into pressure type, centrifugal type, spray fluidization, spray belt type and so on. Various spray granulation methods are different, and the granules of the products are also different.