FANQUN Vacuum Rake Dryers
FANQUN vacuum rake dryers achieve circulating mixing and vacuum drying, providing drying solutions for various materials.
- High vacuum level provides a low-pressure environment, preventing heat-sensitive materials from drying at high temperatures.
- The compact structure maximises the loading volume while saving space.
- Rake agitators gently mix materials, ensuring even heating and preventing clumping.
- Flexible modular design to adapt to different production requirements.
- Energy-saving mechanisms with low-temperature drying and solvent recovery.
ZB Series Vacuum Rake Dryer
Features of ZB Series Vacuum Rake Dryer
- Large heating area,and high heating efficient by design heating by both jacket and blending shaft.
- Blending shaft can rotate reversed So incide of chamber pulpiness, paste-like mixture or powder raw materials can be uniformly dried.
- Rotating direction of blending shaft is reversible,so during operation,raw material is continuously cycle in drying manner.
Application of ZB Series Vacuum Rake Dryer
- The following raw materials in the field of pharmaceutical industry, foodstuff industry, chemical industry and so on can be dried.
- Suitable for pulpiness,paste and powder raw materials.
- Heat sensitive raw materials which need to be dried at low temperature.
- Raw materials that are easy to oxidize, explode, have strong irritative and toxic.
- Raw materials that need to recover solvent.
Energy efficient and has power saving switch, A wide versatile application for chemical and plastic processing.
Ideal for industrial pesticides and sludge, has great pressure control. Manufactured with touch-screen control and button type.
Easy to operate and has versatile application, Various heating methods available for this machine including coal-fired.
Has great drying and dehumidifier function, Enhanced with energy-saving features. Manufactured with durable stainless steel for versatile chemical and plastic processing.
Multi-function and low temperature, The machine’s voltage is customizable and suitable for chemical processing.
Eco-friendly and automatic feature that is suitable for paste and powder materials, Best advantages of the dryer is product circulation and stirring for finer results.
Low energy and high efficiency rate, Steam heating method. Manufactured with stainless steel that prevents any impact dents.
High productivity and efficiency, Wide application of chemical, food and plastic processing, Customization is available.
- Our Factory
- Technical Parameters
| Item | Model | ||||||||
| Name | unit | ZB-0.5 | ZB-0.75 | ZB-1.0 | ZB-1.5 | ZB-2.0 | ZB-3.0 | ZB-5.0 | ZB-10 |
| Working volume | L | 300 | 450 | 600 | 900 | 1200 | 1800 | 3000 | 6000 |
| Heating area | m² | 6 | 7.6 | 9.3 | 12.3 | 14.6 | 19.3 | 26.5 | 41 |
| Stirring revolution | rpm | 6~30 stepless variable | 6~20 | 6~10 | |||||
| Power | kw | 4 | 5.5 | 5.5 | 7.5 | 11 | 15 | 30 | 45 |
| Design pressure of jacket | MPa | ≤0.3 | 0.5 | 0.5 | |||||
| Pressure in the cylinder | MPa | -0.1~0.15 | -0.1 | -0.1 | |||||
Definition of Vacuum Rake Dryers
A vacuum rake dryer is a dryer with a cylindrical body and a large-area interlayer heating system. It has a special rake agitator to mix and lightly crush materials. The vacuum dryers can be divided into dryers, which only the interlayer has a heating medium, and dryers that both the interlayer and the drive shaft have heating media, based on whether a heating medium is injected into the drive shaft.
Working Principle of Vacuum Rake Dryers
The vaporisation point of water decreases because of the vacuum environment in the tank, so the dryer can dry materials at a low temperature.
The interlayer is heated by a medium, and it transfers heat to the inner wall. The rotation of the stirring rod ensures that the material is heated evenly.
After the materials are heated under a vacuum environment, the inner moisture will transfer to the surface and evaporate.
Components of Vacuum Rake Dryers
Tank
The tank body is cylindrical, and there is a fully automatic feeding and unloading port on the top. The sealing device consists of packing seals and mechanical seals. The tank has a large capacity and can adapt to different materials with different moisture content from 15% to 90%, and different properties, like powder, granules, paste, and cream.
The tank body consists of an insulation layer, a heating interlayer, and an inner wall, from the outside in. The insulation layer uses ultra-fine glass wool, providing both insulation and energy savings. The heating interlayer has a large heating area.
Heating System
The heating media can be steam, hot oil, hot water, electricity, fuel, or biomass. For heat-sensitive materials, our precise temperature control system keeps temperature fluctuations within ±1℃. We can set the temperature according to material requirements. The large-area interlayer heating improves the heating speed.
Vacuum System
Usually, the vacuum level is 400-700mmHg. The suitable vacuum level can not only lower the vaporisation point of water, but also prevent reduced heat transfer due to excessively high vacuum. The water evaporated from the material is cooled by a condenser and then removed by a vacuum pump.
Our vacuum rake dryer has a thermal energy utilisation rate of over 85%, higher than the average heat utilisation rate in the drying industry of 70-75%, making it energy-efficient.
Drive System
The drive system is made of a gear reducer, a drive shaft, and stirring rods. The gentle rotation speed and regular operating trajectory resulted in a low material loss rate of less than 0.5%.
Gear reducer: The vacuum rake dryer has a column-shaped gear reducer, which can reduce the rotation speed to a speed suitable for the material.
Drive shaft: It is made of solid 316L stainless steel and is designed with an integral forging process to ensure that it can withstand greater resistance during stirring without breaking.
Agitator: The rake agitator allows the material to circulate and tumble continuously, indirectly heating the material and ensuring it can constantly contact the inner wall for uniform heating. Even paste-like materials can be heated evenly.
The rake teeth at the end of the stirring rod can stir clockwise and counterclockwise. The end of the stirring rod fits tightly against the inner wall while maintaining small gaps. Unlike the ribbon agitator of other dryers, the rake agitator does not simply rotate, but throws the material from one end to the other, which is more precise than the ribbon agitator.
Also, the rotation speed is lower, causing a weaker shear force on the materials. A weak shear force reduces the material damage rate and is suitable for materials that need to preserve crystal structure.
Knocking stick: It is made of stainless steel and is used for crushing materials and accelerating drying speed. You can optionally install.
Control System
It is flexible and can be adjusted and monitored by workers according to material and process requirements. The control system continuously monitors and adjusts temperature, humidity, vacuum level, stirring speed, and feed/discharge control to ensure optimal material drying.
Applications of Vacuum Rake Dryers
Mining Industry
Ores and other minerals: Concentrates, metallurgical raw materials. Vacuum rake dryers can effectively break up wet ore and efficiently dry it. Drying ores can improve their purity, increase their value, and is convenient for subsequent production and processing.
Coke: As a dye, its exposure risk due to moisture in the pores must be avoided during combustion. FANQUN vacuum rake dryer not only thoroughly dries moisture, but its sturdy sealing device also ensures safety during the drying process.
Foods Products
Food ingredients: Dairy products, fruits, vegetables, grains, and meats. nutrients and flavour of dairy products, fruits, vegetables, and meats should be preserved.
Addition agent: Preservatives such as potassium sorbate and sodium benzoate; antioxidants such as Vitamin C; colourants such as tartrazine and amaranth red.
Functional food ingredients: Probiotics, dietary fibre, minerals, and protein powder.
Chemical Industry
Sensitive compounds: potassium permanganate. A vacuum rake dryer can maintain its particle size and chemical stability.
High viscosity polymers: Polyvinyl alcohol (PVA) and polyacrylamide. These high viscosity compounds become more viscous with increasing temperature, making drying more difficult. However, the rake agitator in the FANQUN rake vacuum dryer can bilaterally tumble these materials, preventing them from clumping.
Dye intermediates: Anthraquinone sulfonic acid, diaminoanthraquinone, and salicylic acid intermediates.
Easily oxidizable materials: Organometallic compounds.
Electronics Industry
Lithium iron phosphate: It is a novel positive and negative electrode material for lithium-ion batteries. The quality of lithium iron phosphate is closely related to the battery’s lifespan and safety. FANQUN’s vacuum rake dryer utilises low-speed rake stirring to both dry lithium iron phosphate and preserve its crystal structure.
Nano-oxides: Titanium dioxide. The high vacuum environment and high airtightness of our dryers prevent easily oxidised substances from undergoing oxidative degradation during drying.
Pharmaceutical Industry
Traditional Chinese medicine extracts: Astragalus membranaceus, Salvia miltiorrhiza, Angelica sinensis, and Eucommia ulmoides extracts. Vacuum rake dryers can preserve the nutrients in these extracts.
Active ingredient APIs: Antibiotics, protein drugs, and sterile raw materials. For these APIs with high hygiene standards, it is necessary not only to ensure low heating temperatures but also to achieve a sterile environment.
Our cleaning system is equipped with a SIP device, which can thoroughly sterilise, ensuring that the inner wall of the dryer meets cGMP requirements and protects these drugs from cross-infection.
Additional ingredients: tablets, capsules.
Environmental Engineering
Waste generated by various industries: wastewater, sludge, and solid waste. These materials have a certain viscosity. Through the stirring and drying in a vacuum rake dryer, their weight and volume can be significantly reduced, thus lowering landfill costs.
FANQUN is an ISO9001 certified professional vacuum rake dryer supplier with over 40 years of experience in drying equipment research and development and manufacturing. Contact our drying experts now to get a drying solution for your materials.
Material selection: Ribbon agitators are suitable for materials with a certain viscosity due to their strong mixing power. Rake agitators have a lower rotation speed and less shear force, making them suitable for materials with a certain viscosity but still maintaining a granular texture.
Motion characteristics of a stirrer: The motion trajectory of a ribbon agitator is more complex, and the material is rolled up by the ribbon and dispersed around it, creating strong convection. Ribbon agitators also have greater force and speed, resulting in vigorous mixing of the material. While a rake agitator has a simpler motion trajectory, alternating between clockwise and counterclockwise movements to move the material from one side to the other. Its gentler rotation speed loosens the material while preserving its structure.
Energy consumption: Ribbon agitators operate at high speeds with heavy ribbon, resulting in higher energy consumption. Rake agitators operate at low speeds with lighter stirring rods, and they are often detachable, leading to lower energy consumption.
The operation of the thermometer, hygrometer, and vacuum gauge should be checked regularly.
The adsorbed powder of the vacuum suction port needs to be cleaned after each drying cycle to prevent blockage that could affect the drying speed in the next drying.
The grease of the roller needs to be replaced monthly, ensuring its lubrication and protection functions, and reducing the friction of the rolling shaft.
The materials used in dryers must be selected based on the materials.
For most common materials that are not highly corrosive, toxic, or have no risk of exposure, 304 and 316L stainless steel are economical choices. 316L stainless steel, which contains molybdenum, is commonly used in the pharmaceutical industry for drying.
For materials with high hygiene standards, such as materials used in the pharmaceutical and food industries, highly polished materials should be selected to effectively prevent material adhesion.
For highly corrosive materials such as strong acids and alkalis, materials with high corrosion resistance, such as carbon steel or alloy steel, should be chosen.
The key to reducing costs is shortening drying time and recovering high-temperature steam fully.
When designing a drying system, the loading rate, temperature, and vacuum level are determined based on the material characteristics to achieve maximum drying efficiency. Our dryers can recover high-temperature steam, achieving a recovery rate of over 95%.
The delivery time for standard vacuum rake dryers is 60-90 days, and customised or special models may have a longer delivery cycle.
Customised vacuum rake dryers differ from standard vacuum rake dryers in size, materials, processes, and control systems. Therefore, the delivery cycle for customised ones needs to be appropriately extended based on these requirements. For example, the procurement and processing of special materials such as alloys may take 20-35 days.
