PLG multi-stage fluidized granulation dryer

PLG series multi-stage spray fluidized granulationDrying equipment(Upper exhaust) YesSpray drying equipmentOne of the successful designs to date. It can be applied to various types of products, which are materials that are difficult to form into powder using traditional drying techniques.

PLG series multi-stage spray fluidized granulation drying equipment (upper exhaust) drying technology combines fluidized bed drying technology and spray drying technology to make the shape and size of particles easy to control. In addition, PLG series is often used as spray drying agglomeration or spray drying granulation. It can complete the drying process while maintaining a low powder temperature, and another important function is that it can be perfectly applied to the drying and forming of thermosensitive products.

Advantage:

1. Free flowing powder generated during agglomeration or granulation

2. The generated powder contains a very small amount of dust (referred to as dust-free particles)

3. It can dry many thermoplastic and moisture absorbing products that cannot be processed by other equipment.

4. As the temperature of the particles remains low throughout the entire drying process, it is an ideal drying equipment for thermosensitive products

5. Drying is carried out at lower exhaust temperatures, which is beneficial for efficient energy utilization.

Operation method:

The liquid feed can be a solvent, suspension, or emulsion, and the feed is pumped to the air distributor located at the top of the towernebulizer(Spray gun) in.

The atomizer atomizes the liquid into a high-speed dry air flow, and the atomized droplets generated are driven downward by the airflow towards the built-in fluidized bed, while being dried into particles.

At the same time as the particles enter the fluidized bed, the airflow runs in the opposite direction upwardsdrying towerThe top is expelled.

The finer particles separated from the exhaust air are recycled back into the drying tower.

The fluidization of particles in a fluidized bed, fine powder circulation, and particle movement in a dry airflow occur in an air environment with higher dust density than traditional drying systems. Overcoming the adhesion problem on the surface of particles, particles with high moisture content can be processed.

The moisture content of particles entering the fluidized bed can be controlled within a certain required level, thereby achieving significant particle and structural changes (agglomeration or granulation)

When necessary, the drying and cooling of the product can be carried out in another external fluidized bed connected to the outlet of the built-in fluidized bed.

Control the size, shape, and powder characteristics of particles

Because spray drying and fluidized bed drying processes are combined in a drying tower, the dryer can be operated within a large range of changes in particle size, moisture content and drying air temperature. So as to better control the degree and effect of particle agglomeration or granulation.

In the drying tower of PLG, there are three areas where atomized droplets and dried particles interact and influence each other until the agglomeration or granulation structure is completed.

The first area is around the atomizer: atomized droplets are in contact with each other.

The second area is inside the drying tower: atomized droplets and dried particles come into contact with each other.

3. The third area is located inside and above the fluidized bed: wet particles and dry particles are in contact with each other.

The more thorough the contact between droplets and particles, the larger and more compact the resulting agglomerated or granulated particles will be.

Finer agglomerated powders are obtained at higher outlet temperatures, where the moisture content of particles in the drying tower is lower, resulting in less agglomeration effect. Use cooling air inside the built-in fluidized bed.

Larger agglomerated powders are obtained at lower outlet temperatures, increasing the moisture content of particles in the drying tower and thus enhancing the agglomeration and granulation effects. Heating air is used in the built-in fluidized bed.

PLG can transform the feed liquid into larger agglomerating and granulating particles, and at the same time, it can also obtain finer particles that are usually obtained by other spray drying equipment.

PLG can also operate wet agglomerated particles as powder feed.

Product Application

Chemicals: cleaning agents, dyes, fertilizers, inorganic and organic salts, insecticides, tannic acid, etc

Medicine: painkillers, antibiotics, plasma, enzymes, vitamins, etc

Polymers: e-PVC, styrene, UF, PF resin, etc

Food: coffee, dairy products, egg products, seasonings, maltodextrin, soup ingredients, plant protein, yeast, etc

Development history of our company's PLG series multi-stage spray fluidized granulation drying equipment (upper exhaust)

This PLG multi-stage spray fluidized granulation drying (upper exhaust) technology (called MSD or FSD by German GEA NIRO company) was invented by German GEA NIRO company very early. In 2008, our company sent special engineers abroad to study and map the MSD (FSD) series of spray drying equipment. After more than four years of digestion and innovation, our company developed a set of MSD (FSD) pilot equipment in August 2012 to do experiments and explore technical parameters for customers in the company. At present, the technology for this model is blank in the domestic market. After its launch, the product has received high praise in the Chinese market and has received multiple orders. At present, our company is also promoting this seriesSpray drying towerThis new technology tower has significant advantages over traditional towers in terms of energy consumption, product quality, equipment footprint, cleaning, and environmental protection. We hope that customers can bring materials to our company for experimentation. Some successful cases of multistage spray fluidized dryer by the end of 2012 are attached below for reference:

1. Jilin Jinyi Eggs 3 sets of PLG multi-stage spray fluidized dryers with evaporation capacity of 2.5 tons/hour

2. Yantai Fukang Biological (invested by Taiwan Weidan Group) 1 PLG multi-stage spray fluidized dryer with evaporation capacity of 1.2 tons/hour

3. One PLG multistage spray fluidized dryer with an evaporation capacity of 150 kg/h in Xinjiang Suntory Camel Industry

4. Philippines SUPERSTAR COCONUT PRODUCTS INC. (Philippines New Coconut Line) 1 PLG multi-stage spray fluidized dryer with an evaporation capacity of 150kg

Description of process characteristics of multistage spray fluidized drying equipment (upper air outlet)

Characteristics of high-pressure liquid transportation

A three plunger high-pressure pump that meets food hygiene requirements.

The motor variable frequency adjusts the flow rate, and the fluid output is stable without pulses.

The high output pressure can reach 300 bar.

High pressure pipeline insulation to maintain fluid emulsification and viscosity characteristics.

Spray nozzle atomization characteristics:

High pressure spiral nozzle atomization, atomization angle and atomization pressure can be selected according to material viscosity and atomized droplet diameter. Low temperature air flow protection around the atomizing nozzle, preventing nozzle seals from failing due to high temperature effects.

Characteristics of drying tower:

The air flow model of the drying tower is a mixed flow mode:

The high-speed hot air flow at the top of the drying tower is vertically directed downwards without any deviation, and is fully mixed with the atomized droplets at the center of the hot air outlet to enhance the heat transfer effect;

The hot air jet diffuses to the bottom of the cone of the drying tower and returns upward, separating the dried material from the air. The air forms a circular air curtain on the tower wall during upward movement, isolating the moist powder from the tower wall and preventing powder sticking to the tower wall. At the same time, it increases the drying time of the material and efficiently utilizes the thermal energy of the hot air;

The material is subjected to air separation, and the fine powder is separated and enters the cyclone separator from the circumferential outlet at the top of the tower; Coarse particles fall directly into the fluidized bed at the bottom of the tower;

Internal fluidized bed characteristics

The material undergoes stable and uniform fluidized drying/cooling in a low-temperature and low humidity state within the internal fluidized bed. Minimizing the deposition of materials at the bottom of the tower to the greatest extent possible; It is easier to produce dust-free granular products;

Especially suitable for materials with high fat content, poor thermal stability, thermoplasticity, easy moisture absorption and high moisture content and viscosity, such as dairy products, microencapsulated essence, coffee partner, egg yolk powder, fruit and vegetable powder, etc;

Characteristics of vibrating fluidized bed

Perform final fluidized drying and cooling of the product to obtain dust-free products that meet the specified moisture content and temperature conditions.

The fluidized form adopts piston flow to achieve uniform drying and cooling treatment of the product, maintaining the consistency of product properties.

The frequency and excitation force of the vibration motor can be adjusted to control the time of fluidized drying/cooling.

Characteristics of fine powder return agglomeration process

The fine powder captured from the cyclone separator is sent to the atomization zone of the drying tower through positive pressure air, where it collides and adheres with droplets and wet particles to form agglomerated particles.

Advantages of Upper Exhaust Drying Tower

In general, according to the exhaust form of the drying tower, it can be divided into an upper exhaust drying tower on the tower body, an expanded exhaust drying tower at the lower part of the tower body, and a large curved pipe exhaust drying tower at the bottom of the tower cone. According to the form of dust collection, the tower can be divided into eccentric bag type dust collector, circumferential bag type dust collector, single-stage (two-stage) cyclone dust collector, single-stage bag type dust collector, cyclone bag type two-stage dust collector, and cyclone bag wet two-stage dust collector spray drying tower. The eccentric bag filter and circular bag filter drying tower are connected to the tower body. At the same time, the drying tower can also be equipped with systems or equipment such as fine powder agglomeration, multi spray gun agglomeration granulation, finished product wind conveying, and vibrating fluidized bed. In order to improve the safety of equipment operation, explosion-proof doors and high-temperature alarm devices for the tower and exhaust temperature are installed inside the tower. For users with higher requirements, an automatic control system can be provided. Design a process flow that is suitable for product drying based on the drying characteristics, evaporation capacity, heat source, and other factors of different materials.

1、 According to the direction of hot air and material movement, the lower exhaust tower adopts a downstream drying method, while the upper exhaust tower adopts a mixed flow drying method, which is the difference between the two. Therefore, the advantages of the pressure type upper exhaust spray drying tower over the lower exhaust tower are:

1) Energy saving: As the return air chamber of the upper exhaust tower is located in the high negative pressure zone of the tower, during the evaporation process, the high negative pressure evaporation reduces the evaporation temperature, which saves steam and energy. The upper exhaust tower only consumes 2.8-3.0kg of steam to evaporate 1kg of water, saving 8-10% of steam;

2) Save construction investment: For equipment of the same specifications, the height of the upper exhaust tower is reduced by 5-7m compared to the lower exhaust tower.

3) Good product quality: The particles of the exhaust tower powder are uniform, with fewer larger and smaller particles. Due to the high negative pressure in the drying zone of the powder, which is low-temperature drying, the various vitamins in the powder are less damaged and the protein is not denatured. In addition, due to the shorter heating time of the powder during the drying process compared to the lower exhaust tower in the high-temperature zone, its color, particle size, and blending properties are all better.

4) Easy to clean: The tower structure is simple and easy to manufacture. Due to the direct connection between the columns and cones of the tower, the connections at all angles are smooth and smooth, and there are no dead corners during cleaning. After opening the tower door, it is easy to clean every part that comes into contact with dust.

5) Reduce emissions and save energy to reduce labor intensity: A circular air curtain cannot be formed inside the lower exhaust tower, and the tower wall is heavily covered with dust, requiring daily cleaning. Brushing the tower increases material loss and wastes a lot of hot water. Not only does it consume energy, but it also increases the amount of pollution. The drying process of the upper exhaust tower is mixed flow drying, and the process of mist droplets is constant speed drying with downstream flow during the drying period, and mixed flow exhaust during the deceleration period. The wind reaches the bottom and forms a 180 degree rotation, separating the materials and air during drying. The wind forms a large circular air curtain on the tower wall during rapid upward movement. During drying, a circular air curtain is formed inside the tower, controlling the phenomenon of wall dust on the tower wall. The tower can be cleaned every ten days, reducing the amount of pollution, saving energy, and reducing the labor intensity of workers.

2、 The advantages and disadvantages of the drying tower equipped with different forms of fine powder capture and recovery systems are as follows:

3、 Our companyPressure spray drying towerCharacteristics of

(1) Adopting a four spray gun structure design, the droplets sprayed by each spray gun collide with each other and aggregate into hollow large particles, improving the solubility of the powder.

(2) With 18-20MPa high-pressure spray, the material is fully atomized and fully contacted with the hot air, which increases the heating area, improves the thermal efficiency and makes the product dry instantly.

(3) The air distribution device adopts multiple adjustable air ducts to ensure that the airflow entering the tower is vertically downward, without deviation or vortex. This greatly reduces the dust hanging on the wall.

(4) The exhaust section adopts a four point exhaust system, where the air reaches the bottom and forms a 180 degree rotation, increasing the drying time of the material and effectively utilizing hot air. The uniform exhaust of the equipment reduces dust hanging on the wall, reduces the amount of dust entering the cyclone separator, and improves product yield.

(5) The fine powder from the cyclone and bag filter is re aggregated from the top of the tower back into larger particles, increasing the solubility of soybean powder. Simultaneously protecting the environment.

(6) The powder inside the tower enters the vibrating fluidized bed from the bottom of the cone and is subjected to secondary drying, granulation, and cooling. Improved product quality and increased solubility.

(7) The cooled powder can be packaged after being screened by the vibrating screen machine. The product only has one powder outlet, reducing powder loss and making operation easier. The device has a compact structure.

(8) The method of preheating cold air with condensed water recovers waste heat and also improves the service life of the heat exchanger.

(9) The tower body is a cylindrical body with conical joints, without other complex structures, making it easy to clean or wash.

(10) The tower is equipped with safety riot doors and explosion channels to prevent equipment dust explosions caused by operational errors.

(11) Air hammers are installed at the lower parts of the cone sections of the drying tower, bag filter, and cyclone separator. Pulse controllers are used to intermittently start them in sequence, effectively shaking off any possible powder accumulation in the cone sections in a timely manner.

(12) In order to facilitate the falling of dust on the cone, the cone angle of the tower should not exceed 45 °.

(13) According to the control requirements of each system, various mechanical and electrical equipment can be directly started and controlled on the instrument box, and there are displays of inlet air temperature, exhaust air temperature, tower temperature, tower negative pressure, fluidized bed inlet air temperature, and fluidized bed negative pressure.