LPG type high-speed centrifugal spray dryer

Spray drying is a drying process in which the raw liquid is dispersed into droplets by an atomizer and powder products are obtained through direct contact between hot air (or other gases) and the droplets. The raw material liquid can be a solution, emulsion or suspension, or it can be a molten liquid or paste. The dried products can be made into powder, granules, hollow spheres or agglomerates as required.

The centrifugal spray dryer is a type of hot air circulation, co-current, and centrifugal atomization dryer. The drying medium air is filtered through primary and medium-efficiency air filters, heated by the heater, and then enters the air distributor at the top of the dryer. The hot air spirals evenly into the drying chamber. The liquid material is conveyed by the material liquid pump to the high-speed centrifugal atomizer at the top of the tower. Under the action of centrifugal force, it is sprayed into extremely fine mist droplets and comes into contact with the hot air in the same direction. It can be dried into finished products in a very short time. The finished products are continuously collected at the bottom of the drying tower and the cyclone separator. The exhaust gas, after dust removal, is discharged by the induced draft fan.

The working principle of high-speed centrifugal spray dryer

The centrifugal spray dryer mainly works by distributing the material into droplets through the centrifugal force of the high-speed rotating atomizer, and then drying it instantly upon contact with the hot air passing through the volute hot air distributor. Due to the fact that the material liquid is atomized by being flung out from the edge of the high-speed rotating disc (with a linear speed above 110m/s) under the action of centrifugal force, the diameter of the atomized material liquid is relatively large. Therefore, a larger diameter is required for the drying tower. At the same time, as the material is thrown out by centrifugal force, the relative size of the droplets is relatively uniform. The moment the droplets come into contact with the hot air, they are dried. The droplets are dried into basically hollow powder, and the particle size of the material is relatively uniform, but the particle size of the material is relatively small.

Centrifugal spray dryers are widely used in industry, such as in the chemical, food, and pharmaceutical sectors. When it comes to the materials for spray drying, the various raw materials processed have significant differences in properties, and the various products obtained also have their own special requirements. Therefore, not only do they each have their own particularities in the technological process, but also in the process arrangement, equipment structure, operating conditions, and even in the auxiliary devices.

Features of high-speed centrifugal spray dryer equipment

(1) Spray drying is fast. After the material liquid is atomized, its surface area increases significantly. During the contact with hot air, 95% to 98% of the moisture can be evaporated instantly, and the drying time only takes a few seconds. It is particularly suitable for the drying of heat-sensitive materials.

(2) The product features excellent uniformity, fluidity and solubility. The higher the purity of the product, the better its quality.

(3) The production process of the spray dryer is simplified and the operation control is convenient. For liquids with a moisture content of 40% to 60% (up to 90% for special materials), they can be dried into powder or granular products in one step. After drying, there is no need for crushing or screening, reducing production processes and improving product purity. The particle size, bulk density and moisture content of the product can be adjusted within a certain range by changing the operating conditions, and the control and management are very convenient.

The application scope of high-speed centrifugal spray dryers

(1) Chemical products: polyaluminium chloride, disperse dyes, reactive dyes, organic catalysts, silica, laundry powder, zinc sulfate, silica, sodium metasilicate, potassium fluoride, calcium carbonate, potassium sulfate, inorganic catalysts, various waste liquids, etc.

(2) Food: amino acids, vitamins, egg powder, bone meal, condiments, protein, milk powder, pig's blood powder, soy sauce powder, coffee, tea, glucose, potassium sorbate, pectin, flavors and fragrances, vegetable juice, yeast, starches, etc

(3) Ceramics: alumina, zirconia, magnesium oxide, titanium oxide, magnesium titanate, kaolin, various ferrites and metal oxides, etc

Technical specifications of high-speed centrifugal spray dryer

Photos of high-speed centrifugal spray dryer equipment