Delta - Model DNFD - Nutsche Filter Dryer
DNFD Nutsche Filter Dryers are versatile, multipurpose machines wherein the following operations can be performed: Filtration. It’s due to a process driven by pressure difference ∆P between the two sides of the filtering sheet. Special agitator smoothing movement allows to maintain ∆P also when the cake has already a low liquid percentage. In this way the filtration process reaches a dryness higher than other standard filters, indeed the final squeezed cake is comparable to that obtained by centrifuges.
Washing. Through several cycles of re-slurry and filtration, the machine allows you to wash the product with a suitable solvent and in a more effective way. This process is led by a clockwise agitator movement.
Vacuum drying. After the end of the last filtration the product can be vacuum-dried by means of both bottom and side vessel heating while the chamber is under vacuum. During this step the agitator rotates in counter-clockwise direction.
In some cases it's also possible to blow the product with an inert suitable dry hot gas that can be fed through the bottom of the machine.
Automatic discharge of dried product. Once the product has reached the required dryness level, it is automatically discharged through the side discharge valve.
Because multipurpose machines, Nutsche Filter Dryers greatly improve the product purity and minimize safety and environment problem of manual transport of chemical ingredients.
Application Fields. DNFD is suitable for multi-product or mono-product application accomplished in batch process, such as:
- Pharmaceutical intermediates
- Fine chemicals
- Dye stuff
- Chemical Intermediates
- Food industry
- Inorganic salt
- All fields where the crystals of suspension are the product to be recovered.
- Pharmaceutical, for final oral dosage form pharmaceuticals
- Sterile, for final injectable dosage form pharmaceuticals
- High purity of product
- Optimization of filtration and drying process
- Easy operation
- Low investment & maintenance cost
- Research S development
The DNFD is made up of a cylindrical vertical vessel with convex dished cover and flat bottom head (fixed or lowering). Both the bottom head and shell are jacketed.All the surfaces of the machine feature a heating system, thus improving DNFD drying efficiency.
Cartridge Filter. On the top cover there’s Delta Cartridge Filter for powder captation, a special device essential to keep the vacuum pump free of fly powder particles. It’s easily cleanable by Nitrogen back purge operation.
Delta Heated Agitator Shape. It’s equipped with two or three special blades to perform cake smoothing, pressing, slurry agitation and reslurry, cake mixing and drying, automatic product discharge.
Inner-agitatorMovement. The twofold inner agitator movement, axial and rotating, allows to smooth the cake during the filtration so as to close the cracks that could sensitively reduce the pressure filtration effectiveness. Moreover the product movement during the drying step increases the heat exchange.
The internal agitator is built to allow:
- CW and CCW rotation
- Raising and lowering movement
Both of them with variable speed. Provided with a double dry mechanical seal or gas lift off seal coupled with metal bellows.
Lowering Bottom and Filter Sheet
Delta provides its machine with a special design equipment for highly efficient drying and shorter filtration time.The lowering bottom allows easy cleaning, inspection and maintenance activities. It’s provided with a perfectly aligned hydraulic drive. Clamps or bayonet closure are available.The filtering sheet is placed on the bottom head, it can be supplied in different types according to the process requirements.
Delta sterile side Discharge Valve
DNFD is equipped with a plug type valve positioned on the shell that can be manual or automatic. Its special sealing design allows sealing also in worst condition thus guaranteeing product high purity.It’s easy to open for access, cleaning and maintenance operations. It’s equipped with hydraulic drive screw, metal or Teflon bellows.
Nutsche Filter Dryer
Vessel rotation ( about 30°) for complete heel removal
Delta Ultra Dry: The new filter sheet design is particularly suitable for high pressure from the bottom. This reduces deformation of filter sheet and allows better drying performances due to a FLUID BED EFFECT. Furthermore the system allows a better product discharge.
- 90% of residual heel recovered by Delta Ultra Dry, with fixed machine
- 100% of residual heel recovered by Delta Ultra Dry & inclination
- CIP with spray rotating washing balls that can be extractable
- Sintered stainless steel wire mesh cartridge sterilizable on vacuum line and easy extractable
- Hydraulic power pack
- Electrical and hydraulic panel
- Sample port Instrumentation
- Condensation unit
- Vacuum unit
- Control system with PLC
- Local operator interface
- Hot water production unit
Available with the following construction materials:
- Austenitic stainless
- Nickel based Alloy
- 904L, duplex stainless steel
- Other materials on request
Design and construction according to the highest quality standards:
- FDA and GMP
- ASME BPE
- ASME U-Stamp
- ATEX All main international codes