Delta Nutsche Filter Dryer

Delta Nutsche Filter Dryer

Nutsche Filter Dryer

The Delta Nutsche Filter Dryer offers filtration and drying in one batch machine.

It can perform filtration, washing, vacuum drying, and automatic discharge of the dried product. Consolidating the process steps alleviates the need for multiple machines. This filter dryer can handle even the most difficult liquid separation. The shape of the impeller provides gentle cake squeezing, and the filtering sheet is designed for backpressure. The agitator reverses direction, and with its special shape pushes the product through the discharge nozzle and automatic valve for automatic discharge of dried product.

Typical Applications:

      • API production
      • Fine chemicals
      • Plastics
      • Dietary supplements/fragrances
      • Chemical Intermediates
      • Precious metals/Metals recycling
      • Catalysts

Production Cycle

Filtration

With Delta’s Agitated Nutsche Filter Dryer, the filtration process reaches a higher dryness than with other standard filters. Thus, the final squeezed cake is comparable to those obtained by centrifuges.

Washing

Through several cycles of slurries and filtrations, the machine allows you to wash the product effectively with a suitable solvent. This process is led by a clockwise agitator movement.

Vacuum drying

The product can be dried by means of both bottom and side vessel heating while the chamber is under vacuum. In some cases, it is also possible to blow the product with a suitable inert, dry, hot gas.

Automatic discharge of dried product

Once the product has reached the required dryness level, it is automatically discharged through the side discharge valve.

Typical Applications

  • API production
  • Fine chemicals
  • Plastics
  • Dietary supplements/fragrances
  • Chemical Intermediates
  • Precious metals/Metals recycling
  • Catalysts

Highlights

  • Filtration: Pressure-driven filtration is enhanced by the agitator. The shape of the impeller provides gentle cake squeezing, and the filtering sheet is designed for backpressure
  • Washing: To remove product impurities and increase quality, advanced devices can treat and reslurry the same crystal multiple times
  • Vacuum drying: By reducing the internal pressure and controlling all internal surface temperatures, the drying is highly efficient, and process time is reduced  
  • Automatic discharge of dried or even wet product: The agitator reverses direction and, with its particular shape, pushes the product through the discharge nozzle and automatic valve

Consolidating the process steps alleviates the need for multiple machines with safety, quality, and economic benefits.

  • Safety is improved by minimizing the contact between the product and the environment, and between the product and personnel
  • Improves product purity and reduces losses related to the transportation of chemical ingredients 
  • Installation and operating costs are lower than other process solutions
  • Filtration and drying processes can be optimized together, leading to better results in terms of product quality
  • High-potency products are more easily managed when using a single machine for several operations

The agitator can rotate in both directions and can be lifted or lowered, according to process needs.

  • During filtration, the agitator squeezes the cake
  • During product washing, the agitator mixes and reslurries the product
  • During drying, the agitator maximizes surface contact areas 
  • During discharge, the agitator pushes the crystals to the discharge nozzle. The speed and direction of the agitator control the rate of discharge 
  • Designs can be totally customized 
  • The filtering sheet can be equipped with a multi-layer metal filtering media or a textile filtering sheet
  • NEW OPTION: Delta side withdrawal system (EU patent EP 3 322 498 B1) improves filtration performance by incorporating the sedimentation behavior of some products (decanting)

Discharge

  • The discharge nozzle is located on the side of the machine just above the filtering sheet
  • Solids products can be discharged wet or dry
  • The agitator pushes the crystals to the discharge nozzle. The speed and direction of the agitator control the rate of discharge
  • Side discharge valve
    • Circular plug type and contoured to the vessel to minimize dead space
    • Manually or automatically driven by drive screw
    • Shaft protected by metal or PTFE bellow
    • Adapted to both main packaging or high-containment devices

Special Options:

  • 95% of the residual heel is recovered by Delta Ultra Dry with a fixed machine
  • 100% of the residual heel is recovered by Delta Ultra Dry with the tilting option
  • Tilting system (15-30°) improves machine discharge performance, helping the product move to the discharge nozzle, and in the case of total rotation, the machine also becomes a reactor, combining reaction, crystallization, filtration, and drying
  • Delta Ultra Dry for DNFD – a custom filtering sheet design that allows the blowing of nitrogen from the lower side
    • During drying, operation time and heat transfer are improved by generating a fluid bed drying effect, and nitrogen, as a sparging gas, favorably shifts the partial pressure of the vapor or moisture
    • In the filtration phase, the nitrogen can help to unclog the filtering sheet
    • During discharge, the nitrogen helps to remove the heel cake for complete discharge from the main vessel

Control Options

  • Hydraulic power pack
  • Electrical and hydraulic panel
  • Sample port Instrumentation
  • Control system with PLC
  • Local operator interface

Machine Characteristics

  • The DNFD core equipment is a vertical, cylindrical vessel with a dished cover and a flat lowering bottom that supports the filtering system—typically jacketed for temperature control and suitable for both pressure and vacuum operation 
  • cGMP, cGMP sterile, and EHEDG designs
  • Contact material: AISI316L, AISI904L, C-22, C-276, coated with elastomers
  • Filtering sheet: Metal grid as well as fabric filter
  • Surface finishing: From pickled and passivated to mirror polished
  • Sealing system: From stuffing box to lift off double mechanical seal
  • Certification: PED, ASME, HP0, Selo, ATEX
  • Construction Materials: Austenitic stainless steel, nickel-based alloys, 904L, duplex stainless steel, and other materials on request

Custom Options

  1. CIP system: For washing between batches, which uses rotating spray balls and sprayers on critical areas of the discharge valve
  2. SIP system: Blows steam inside the machine body and checks cold area temperatures for sterilizing grade control
  3. Sanitary insulation: Which is mandatory for applications where cleanliness is important, like in white chambers (clean rooms)
  4. Sampling device: For retrieving a product sample and checking the production status
  5. Additional delumper: For products that tend to form lumps
  6. Dust filter on the top head: For product containment while avoiding vacuum pump contamination
  7. Flat bottom lowering and bayonet closure system for easy maintenance management
  8. External vacuum system coupled with an integrated heating system: For global production line management
  9. Options for high-containment devices: For high-potency products, with a glove box at the discharge nozzle or at the sampling port

Standard Sizes and Technical Data

Keep in mind that we can customize our machines for all of your drying needs.

Model Nominal Surface
(m2)
Nominal Capacity
(l)
Agitator Stroke
(mm)
Cake Volume
(l)
Internal Diameter
(mm)
Cylindrical Height
(mm)
DNFD 25 0.3 160 150 40 600 500
DNFD 50 0.5 400 200 100 800 800
DNFD 100 1.0 1,200 300 300 1,200 1,000
DNFD 150 1.5 1,400 350 525 1,400 1,000
DNFD 200 2.0 3,000 350 700 1,700 1,200
DNFD 300 3.0 3,650 450 1,350 2,000 1,200
DNFD 400 4.0 5,000 500 2,000 2,300 1,200
DNFD 500 5.0 6,400 500 2,500 2,600 1,200
DNFD 600 6.0 7,400 600 3,600 2,800 1,200
DNFD 700 7.0 8,500 600 4,200 3,000 1,200
DNFD 800 8.0 9,500 600 4,800 3,200 1,200

Pilot Units are available with the following standard measurements

 

Model Nominal Surface
(m2)
Nominal Capacity
(l)
Cake Volume
(l)
DNFD 08 0.08 20 3
DNFD 10 0.1 40 12
DNFD 20 0.2 100 30
DNFD 30 0.3 170 40

Check out our other filter/vacuum drying solutions.