PSL Agitated Nutsche Filter Dryers (ANFD)

Powder Systems Limited’s (PSL) unique technology enables reliable production scale-up and helps overcome traditional product development issues such as batch reproducibility and product uniformity. PSL’s technology can be used at all levels of production from R&D to pilot-scale and large-scale commercial manufacturing.

Filter Dryers combine the function of filtration with drying. They are not just filters that dry (this occurs when an inert gas is passed over a wet cake sitting on a Nutsche filter and is not repeatable). A filter dryer incorporates both unit operations via the use of low RPM, high torque agitator that turns over the solids in the cake to facilitate faster, more thorough and repeatable drying. In the PSL lab and production scale systems, the agitator can be set via recipe to a specific depth within the cake in order to exactly quantify drying within a batch. With the use of the programmed automation features, these specific multiple height settings and agitation speed can be repeated from batch to batch to provide the exact same drying profile with each experiment or production run.

What sets PSL small scale filter dryers apart is that the automation functions are incorporated into the small dryers we offer. Thus, data that is a function of defined experimentation (agitator height, RPM, inert drying gas flow) can be captured for scale-up.

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  • For both small-scale process development to large-scale manufacturing
  • Ergonomically designed filtration and drying solutions
  • Optional integrated containment systems
  • Simultaneous agitation and inert gas drying

PSL’s Agitated Nutsche Filter Dryers (ANFD) production systems were developed to efficiently wash and isolate solids in the most complex chemical synthesis processes and challenging production environments. This solution is designed to overcome well-known challenges faced by manufacturers when using traditional production methods, such as Büchner filtration and oven tray-drying.

PSL’s ANFD is an All-in-One piece of equipment designed to comply with Good Manufacturing Practices (GMP) for regulated development and production activities. It allows process developers and manufacturers to complete a wide range of processes into one single system such as:

  • Slurry filtration
  • Product washing
  • Re-slurry
  • Vacuum dryer
  • Product sampling
  • Product discharge

Each of the filter-dryers consists of an agitated vessel designed to work under vacuum and under pressure. The vessel can be made of either stainless steel or alloy 22 and can be coated with specific materials such as PFA (perfluoroalkoxy alkane). It is also equipped with a heated jacket and heated agitator for efficient product drying and mixing.

These high containment systems guarantee operator protection and operate under negative pressure HEPA-filtered atmosphere. PSL isolators have been used globally to process highly potent compounds requiring extremely low Occupational Exposure Limit (OEL) such as 20ng/m3. These compounds can include High Potency Active Pharmaceutical Ingredients (HPAPI), cytotoxic and other hazardous substances.

Upon process completion inside a PSL filter-dryer, your valuable product can be recovered very simply by utilizing the PSL agitator to automate the discharge process. Subsequently, the remainder of your batch – also called product heel – can be collected following the ‘’Direct Heel Recovery’’ method originally pioneered by PSL in the industry several decades ago. This method has proven to be the most efficient for high yield productivity and it consists of manually raking the product heel into a PSL high containment off-loading glovebox (ergonomically designed and integrated by PSL). This ensures a full product recovery under safe conditions for your operators, product and environment.  PSL gloveboxes can be manufactured to comply with industry practices (cGMP, GAMP, etc.), directives (ATEX, etc.), regulations (21 CFR Part 11, etc.) and initiatives (PAT, etc.)

Filtration Area 0.05m² 0.125m² 0.3m² 0.6m² 1.0m²
Filter Cake Volume Range 1 to 10L 2.5 to 50L 6 to 120L 12 to 240L 50 to 400L
Filter Cake Height Range 20 to 150 mm 20 to 200 mm 20 to 400 mm 20 to 400 mm 50 to 400 mm
Max Liquid Volume 20L 100L 270L 600L 1000L