What is Agitated Nutsche Filter Dryer/ ANFD?
Agitated Nutsche Filter Dryer (shortened as ANFD) is a closed vessel working to separate solid and liquid by filtering under either high pressure or with the assistance of vacuum conditions. ANFD is high-quality equipment that can be used for the pharmaceutical, chemical, fine chemical, and food industries.
Nutsche Filter Dryers have been specially designed to guarantee the obtaining of pure substances which are free from polluting elements. Designed in accordance with the GMP standards, for all types of pharmaceutical and fine chemical applications.
Why use a closed vessel design?
An Omni-sealed vessel provides an odorless, contamination-free, non-pollution working environment. Within the filtering applications, there are products that, due to their special hazardous or toxic characteristics, or prevent cross-contamination, are more desirably treated in a hermetic way during their manufacturing process. This can maintain product purity and hygiene. highly preferred by users and buyers.
The washing liquid is better controlled and recycled to reduce the wastage quantity. Meanwhile to save washing liquid consumption.
The filtering process carries out 1-2 times upon filtering result, the filtered wet cake is ok to be recycled. Re-mixed and washed with water or other organic solvents. The wet cake discharge is automatic. If the ANFD has an incorporated drying function, we can use it to dry wet cake directly.
What’re major parts of the Agitated Nutsche Filter Dryer/ANFD
What’s the working steps of the Agitated Nutsche Filter Dryer/ANFD
Smoothing and compression
The mixture or mass is loaded into the filter preferably by gravity flow from the reactor which is installed on top of the filter. Or loading carries out via slurry pump if there is a limitation in the room height, the material reactor cannot be installed on a high level.
While loading mixture or mass into the filter, the filtrate starts passing through the filtering cloth under pressure or gravity. for the initial filtration, better to lower the agitator to the down most position to increase the filtration rate and make sure filter media is clean. Make the best use of the first-time sediment. During this process, the wet cake/filtered cake builds up gradually.
Washing liquid fills into the vessel chamber via a strong spray ball. the washing liquid sprays onto the wet cake repeatedly while the agitator stirs the sediment slowly to squeeze out filtrate.
Smoothing and compression:
At the end of the filtering process mentioned above, the agitator lowers to the wet cake surface to smooth out the cracks that appear in the cake. This function reduces 10-20% moisture when compared to other types of filters. Less moisture, less drying time, and energy in the final drying process. The specially designed hydraulic system contributes to the compression of the cake. This smoothing compression gives a systematic, efficient and productive filtering result.
Filtering Cake Drying
There are two types of drying: vacuum and convection which largely depend on product properties.
Vacuum drying is the most used way to dry the mass, needs a vacuum source, agitation, and dust filter.
Convection drying needs hot pressurized gas. (nitrogen is used due to its clean behavior)
The drying process ensures you get a completely drying material out from the biomass, the final product moisture should be less than 0.1%.
Before discharging, the Agitated Nutsche Filter Dryer may need to be chilled down to an ambient temperature. The agitator rotates and lowers to cut away the upper surface off the filter cake. As the blades descend into the cake mass, the discharge valve is open and a controlled discharge of the cake is achieved.
Movement of agitator
The agitator has an up/down moving function while stirring. The different movement carries out for the different processes.
1. Clockwise stirring: smoothing the cake surface and compressing it during the Filtering process.
2. Anti-clock wise stirring: to rotate near filtering media to keep it away from sedimentation, reslurring while washing, and atomized discharging.
3. Upward lifting: the hydraulic cylinder moves at a constant speed During lifting and mixing.
4. Downward compressing: the hydraulic cylinder moves with variable speeds to help to squeeze and discharge
The Nutsche Filter Dryer (shortened as ANFD) is applicable in pharma and food industries, especially for critical hygienic production conditions. A wide range of filtration can use it.
The hydraulic cylinder works on the detachable bottom and there is zero leakage.
The significant squeezing of filter cake, therefore resulting in considerably low residual moisture in the cake, resulting in a reduction in energy requirement for drying of filter cake by up to 40% depending on cake.
The Nutsche Filter Dryer (shortened as ANFD) is possible for Vacuum or pressure filtration.
The inert gas atmosphere is available when incorporated with a nitrogen filling system.
An enclosed vessel to create minimal contamination of the filtering cake.
A very high solvent recovery, very little wastage.
Manpower saving considerably
No toxic gas or vapor releases into the atmosphere due to closed design.
Staff safety is ensured, the heat transfer surfaces can be provided to maintain filtration temperature