Spray drying is a method in which systematic technology is applied to material drying. After the material in the drying chamber is atomized, it contacts with hot air, and the moisture vaporizes rapidly. This method can directly dry the solution, emulsion and suspension into powder or granular products, which can save the process of evaporation and pulverization.
For spray drying of milk powder, a large ultra-fine spray dryer is required. Fast speed, high efficiency and high quality of finished products. It can bring higher economic benefits to the enterprise.
Types Of Spray Dryer
Spray Dryer Granulation Method
The granulation methods of spray dryer mainly include pressure type, centrifugal type and airflow type.
(1) Pressure spray drying method:
Principle: Using a high-pressure pump, at a pressure of 70 to 200 atmospheres, the material is passed through an atomizer (spray gun) to be aggregated into mist-like particles and directly contacted with hot air for heat exchange, and drying is completed in a short time.
(2) Centrifugal spray drying method:
Principle: The centrifugal force is applied to the solution by a high-speed rotating disc, so that the solution is thrown out at a high speed to form a film, filament or droplet, and then due to the friction, obstruction and tearing of the air, the liquid is thrown from the disc along the spiral line. After coming out, it is dispersed into very tiny droplets, and at the same time, the droplets fall down by gravity.
(3) Air-flow spray drying method:
Principle: The wet material enters the dryer through the conveyor and the heated natural air at the same time, and the two are fully mixed. Due to the large heat and mass exchange area, the purpose of evaporation and drying can be achieved in a very short time. The dried product is discharged from the cyclone separator, and a small part of the fly powder is recycled by the cyclone dust collector or the bag filter.
Introduction of large ultra-fine spray drying unit:
The large-scale ultra-fine spray dryer is mainly suitable for the production of micro-granular powder in food, medicine and chemical enterprises, and has broad-spectrum applicability to all solutions such as emulsions and suspensions.
Applicable industries and materials:
Chemical industry: sodium (potassium) fluoride, basic dyes and pigments, dye intermediates, compound fertilizers, catalysts, etc.
Food industry: fat-rich milk powder, gluten, milk powder, milk replacer powder, blood hunting powder, egg white (yolk), etc.
Food and plants: oats, chicken juice, coffee, instant tea, seasoning meat, protein, soybean, peanut protein, hydrolyzate, etc.
Sugars: corn steep liquor, corn starch, glucose, pectin, maltose, potassium sorbate, etc.
Ceramics: alumina, tile materials, magnesia, talc, etc.
Composition and structure of large ultra-fine spray dryer:
One: feeding system
The material is pressed into the atomizing spray gun by the feeding pump, and the feeding system is interlocked with the outlet air temperature to ensure the stability of the material at the outlet.
Two: heating system
Including filter, blower, heater, inlet air temperature sensor, etc.
After the natural air is passed through the steam heat exchanger and the high-temperature and high-efficiency filter by the blower, the hot air is heated to 100 ℃, and then enters the hot air distributor.
Inlet air temperature sensor, showing the heating temperature.
The heater system uses steam heat exchange and flow proportional control valve to work together.
Three: Atomization system
Including atomizing tower, forced distributor, rapping hammer, outlet air temperature sensor, pressure sensor in tower.
The hot air is sent into the forced distributor and comes out through the air equalization plate of the atomization tower. Make sure to get full contact with hot air and dry quickly.
The pressure in the tower is reflected by the pressure sensor, and the rapping hammer can vibrate the material on the wall of the cone barrel. The outlet temperature sensor reflects the temperature of the dried material and the hot air of the carrier medium.
Pressure sensor: The pressure in the reaction tower, if the pressure is lower than the set value, the system will alarm and display the sealing of the detection pipeline and the see-through door. When the pressure is higher than the set value, please check the clogging of the cloth bag.
Rapping hammer: Vibrate the inner wall of the cone barrel of the atomization tower, and vibrate the material on the inner wall of the cone barrel to the bottom of the tower.
Powder conveyor: send the material at the bottom of the tower into a single cone system.
Four: material collection system
Including bag filter, bag pulse rapper, differential pressure gauge, cyclone pressure isolation powder conveyor.
Differential pressure gauge: clamped at both ends of the bag to detect whether the bag is congested. When the value of the differential pressure gauge is greater than the set value, it will alarm and prompt to replace the bag.
The products produced by the large-scale ultra-fine spray dryer have good uniformity, fluidity and solubility, high purity and good quality. The production process is simplified, and the operation control is very convenient. For liquids with a moisture content of 40-60% (up to 90% for special materials), it can be dried into powder products at one time. After drying, there is no need to pulverize and screen, reducing production processes and improving product purity. The particle size, bulk density and water content of the product can be adjusted by changing the operating conditions within a certain range, and the control and management are very convenient.
Introduction Of Small Spray Dryer:
The small spray dryer disperses the material to be dried into very fine mist-like particles through mechanical action, (increases the area of water evaporation, accelerates the drying process) and contacts with hot air to remove most of the water in an instant, so that the The solid matter in the material is dried to powder.
Small spray dryer and its main application in universities, research institutes and laboratories of food, medicine and chemical enterprises to produce micro-particle powders, it has broad-spectrum applicability to all solutions such as emulsions and suspensions, and is regulated into liquid gas by peristaltic pumps. When it comes into contact with hot air, it is heated at a high temperature in an instant to obtain the desired substance. It is suitable for drying of heat-sensitive substances such as biological products, biological pesticides, enzyme preparations, etc.
Small Spray Dryer Model
The small fog dryer realizes the instantaneous drying of the material at low temperature at the inlet air temperature, avoiding the destruction of the activity or structure of the material during the drying process, such as biological products such as enzymes, live bacteria, and heat-labile polymer materials. It provides a very convenient and safe drying method for heat-sensitive materials, etc.
The whole machine of the small spray dryer is made of stainless steel and has a two-fluid spray atomization structure. The spraying, drying and collecting system is made of transparent high borosilicate heat-resistant glass material. Good thermal conductivity, non-breakable and anti-static. Suitable for sugar-free, non-sticky materials.
When the organic solvent concentration in the material is too high, flammable or the material should be oxidized, the machine can use nitrogen to replace the air in the drying atomization system. Oxidized.
Features of small spray dryer:
1. It adopts a large LCD screen for operation, which combines automatic control and manual control. The parameters are displayed in LCD, which is easy to operate.
2. In the design of drying temperature control, the real-time constant temperature control technology is adopted to make the temperature control more accurate, and the heating temperature control accuracy is ±1℃.
3. The drying speed is fast, the surface area of the material liquid is greatly increased after atomization, and it can be evaporated instantly in the hot air flow.
The spray dryer produced by ZZKD has stable performance and easy operation. In addition, we have household food freeze dryers and other laboratory equipment. 13 years of production and export experience and a series of ISO9001 and CE certificates, with warehouses in the United States, Spain and Thailand.
If you want to know about our products, or want to buy our equipment, please feel free to contact us, ZZKD will provide you with the best prices for spray dryers.