50-1000 Microns Powder Laboratory Vacuum Dryer Spray Atomizer

RZL Series Spray cooler / cooling granulation device

Integrate spraying, drying fluid granulating in one body to realize granulating from liquid in one step. Using the process of spraying, it is particularly suitable for micro auxiliary raw materials and heat sensitive raw materials. Its efficiency is 1-2 times than FL boiling granulating machine. The final moisture of some products can reach to 0.1%. It is equipped with powder returning device. The rate of granule forming is more than 85% with 0.2-2mm of diameter. The improved inner roller multi-flow atomizer can treat the liquid extract with 1.3g/cm3 of gravity. At present, this series of machine we can make the type of PGL-150B which can process 500kg/batch.

The importance of melting characteristics

The melting formation of the product can be represented by a solidification curve. When the molten droplets are in contact with the cold air ambient atmosphere, the melt is cooled to solidification temperature. During the release of the curing heat of the product, condensation occurs subsequently at a sustained temperature (condition). Once it is no longer a stream In the bulk state, the droplets will be further cooled to a stable solid particle shape.

Fine particle products

The best treatment method is to atomize the molten liquid with a high-speed rotating atomizer in a co-current cone (relatively small diameter) cooling tower. Most of the products are collected directly at the bottom of the cooling tower, and the fine powder is recovered through the cyclone separator.

Particle size range: 50-150 microns

Coarse particle products 　　

The single-fluid pressure nozzle installed in the cone of the spray tower sprays the uniform cold air flow (the cold air is evened by the air distributor installed on the top). This method is the best method for producing coarse-grained products. The method of product trajectory and fountain type can solidify the molten droplets into a coarse grade in a relatively small volume cooling tower.

Particle size range: 150～300 microns

Oversized particle products

The super-large granular product is atomized and processed by a low-speed rotating atomizer in a cooling spray tower with a large diameter. Although the conical tower meets the requirements, in order to reduce the height of the building and simplify the support requirements of the tower, a flat bottom design is usually recommended. A set of rotating sweeping device sweeps the cooling product at the bottom of the tower to the side discharge port or recovers it with a cyclone separator through the central exhaust pipe.

Particle size range: 300～1000 microns

Technical characteristics:

● The specially designed vortex air distributor, based on the basic principles of aerodynamics and fluid mechanics, strengthens the mass and heat exchange between the cold air and the hot melt droplets. At the same time, the system adopts a counter-parallel flow method to ensure hot melt fog. The droplets are fully and effectively cooled by cold air to complete the cooling granulation process.

● The prilling tower adopts a jacketed air-cooling device to ensure that the inner wall of the prilling tower does not cause "hot melt wall hanging" phenomenon.

● The patented "low-hat" exhaust structure device ensures that more than 90% of the finished products are collected at the bottom of the prilling tower, and only a small amount of fine powder enters the cyclone separator, reducing the gas-solid separation pressure of the cyclone separator.

● The air entering the prilling tower system is filtered through three stages of primary, middle and sub-high efficiency, and the purification level reaches 300,000 or more.

● The inner wall of the granulation tower, the powder pipe, and the cyclone separator are made of SUS304/BA mirror-finished stainless steel. The welding seam is all treated by argon gas shielded welding. "Powder accumulation" phenomenon. The powder outlet pipeline and cyclone separator are equipped with a quick-opening cleaning port, which is convenient for disassembly, cleaning, disinfection and sterilization, and fully meets the food hygiene requirements.

● The product recovery system is equipped with a special secondary fluidized bed cooling and drying device to re-cool and dry the fine powder after spray granulation. The finished product after filling and cooling and drying has good fluidity and low temperature, and can be directly packaged.

5. Plant characteristics

It can produce spherical particles with beautiful appearance.

The appearance of the particles is neat and beautiful

Narrow particle size distribution

The particles are not powdery and have low dusting

It can produce particles with great fluidity, good mechanical strength and not easily damaged.

It is easier to achieve continuity, automation and labor reduction in feeding, feeding, batching, mixing, metering and packaging.

Improve solubility

Improve the working environment

This device is easy to operate, can be automated, and is easy to maintain.

Use the combination of equipment to achieve continuous unmanned operation.

This device is most suitable for large-capacity continuous granulation.

F. The device is vertical and can be installed outdoors with a small area.

6. Design case introduction:

Introduction Design Plan 1:

According to material characteristics) Cooling spray granulator (microsphere) This equipment is mainly used for spray cooling and granulation of molten chemical materials such as polyethylene fat, paraffin wax, amino fat, glycerate and rubber plastic additives, and can meet various requirements of customers for product particle size. Spray cooling products In the spray cooling/spray condensation process, the melt spray enters the cooling tower to form spherical particles. Spray cooling The cooling process is completed by introducing sufficient low-temperature air. The melt is atomized or granulated by a rotary atomizer equipped with a specially designed runner, and can also be atomized with a pressure nozzle or a dual-flow nozzle. Spray cooling is used in the chemical, food and pharmaceutical industries. It is a suitable method to process molten materials into free-flowing particles and to control the particle size.

Melt characteristics

When the atomized droplets of the melt come into contact with the cooling air, they can be cooled to a solidified state. The coagulation process of the pure substance occurs under constant temperature conditions formed during the process of releasing the heat of solidification of the product. Not all melts have a definite freezing point, and the phase change may occur within a temperature range, or it may be from the melted phase without releasing all of the solidification heat to an amorphous solid because of the amorphous structure process. The atomized droplets may also be in a subcooled state below the freezing temperature. It is very important to use data to explain the physical properties and solidification properties of the melt. Based on this, we decide the size of the cooling tower, choose the method of atomization, and decide whether to choose the gas co-current or counter-current mode during the cooling process. In some cases, the two-stage cooling method can show advantages.

Design selection

The fluidized bed cooling device cooled with ambient air is most suitable for the two-stage cooling method, and a pneumatic conveying system with cold conveying air can also be used. The design selection is also based on the requirements of the particle size of the finished product, which can range from fine particles, coarse particles to extra coarse particles, and coarse particles to extra coarse products. Optimize cooling energy consumption and product quality Equipment operating in warm climates may need to dehumidify and cool the air before entering the spray cooler. To reduce additional energy consumption, process air is generally recycled to minimize the load on dehumidification and cooling equipment. The design of the recirculation system allows gas to be released from the system and can be introduced into ambient air, with a certain degree of evaporation accompanied by spray cooling. The multi-channel air door installed in this circulation system allows the equipment to operate in an open cycle without the need to start dehumidification and cooling equipment, so that operating costs can be reduced in cold and dry seasons.

Operating equipment

Introduction Design Plan 2:

(The parameters are determined according to the particularity of the material)

Granulation drying is a widely used process for liquid molten materials. Most suitable for melt and plastic paste liquid waxy solid, granular or spherical solid products. Therefore, when the particle size distribution, residual moisture content, bulk density and particle shape of the finished product must meet precise standards. Granulation drying is a very ideal process.　

Principle:

The air is cooled by the surface of the filtered air and enters the air distributor on the top of the dryer. The hot air enters the prilling tower uniformly in a spiral shape. The material liquid passes through the granulating atomizer at the top of the tower body and atomizes into liquid beads. The tower body forms a co-current and counter-current flow to form a mixed flow, which increases the heat transfer efficiency. It can be solidified and dried in a very short time in contact with cold air. For the finished product. The finished product is continuously output from the bottom of the drying tower and the cyclone separator, and the exhaust gas is evacuated by the fan.

Features:

The cooling speed is fast, and the surface area of ​​the molten material is greatly increased after atomization. In the cold air flow, 70% to 80% of the heat can be evaporated instantly, and the drying time is only a few seconds. The product has good uniformity, fluidity and solubility, The product has high purity and good quality. The production process is simplified and the operation and control are convenient. For special materials, the yield of 40-80 mesh can reach 85%, and the yield of 30-80 mesh can reach 95%. It can be dried into microcapsule products at one time. After drying, there is no need to screen, which reduces the production process and improves product purity. The product particle size, bulk density, and moisture can be adjusted by changing the operating conditions within a certain range, and the control and management are very convenient.

Uses: Plastic additives, food additives, chemical additives, stearic acid, monoglyceride, paraffin wax and other solids.

7. Applicable products:

Organic Industry:

Higher fatty acid (stearic acid, amino fatty acid, etc.), palm oil

2. Stability of polyvinyl chloride (lead stearate, cadmium stearate, zinc stearate, etc.)

3. Aliphatics, glycerol (acid) fat, tallow, etc.

4. Petrochemical (paraffin, etc.)

5. Synthetic resin (phenol resin, petroleum resin, bisphenol A, etc.)

6. Aromatics (asphalt tar, anhydrous phthalic acid, terephthalic acid, anhydrous maleic acid)

7. Fertilizers (urea, nitric acid, etc.)

8. Heterocyclic compounds (caprolactam, etc.)

Inorganic industry:

9. Sodium hydroxide (caustic soda), sulfur, calcium chloride

Schematic for product shaping process