Defining Particle Control
Different processes have different goals for particle control or clarification. To simplify this discussion, we will define particle control as the removal of larger solids carried in the fluid stream, usually particles larger than 1 to 3 microns. For purposes of this page, clarification will be defined as control of smaller particles that may be suspended in a stream and may cause a haze. Clarification may also be part of a prefiltration process designed to remove both particles and larger microorganisms to protect more expensive and critical membrane filters used downstream.
Premature Filter Fouling
In all cases, particle removal/clarification is critical to the efficient operation of downstream processes and the quality of the final product. One way that particles interfere with efficient operation is by causing downstream filters to foul prematurely. Premature filter fouling may interrupt production and increase costs unnecessarily.
This section focuses on particle removal. Our Bioburden Reduction in Biopharmaceuticals page has a more detailed discussion about reducing the number of microorganisms that may be in the fluid stream.
Sources of Particles
Particles can be brought into the process with ingredients from outside sources. They can be undissolved powder nutrients, crystals formed during a mixing process or particles that enter the system with raw materials. Of course, even the microorganisms used in the production of biopharmaceuticals, or their fragments, are particulates to be controlled.
Particle Removal/Clarification Filters in Biopharmaceutical Production
Custom systems are designed for new applications and to solve challenges in existing processes. Critical Process Filtration will work with you to design, build and install a cost-effective system that delivers the results you need. Contact us or visit our custom filtration systems page for more information.
For more information on specific applications, click on the links below to download an Application Summary.
Choosing the Right Filter Media
Almost all particle removal filtration applications are done using depth filtration media. Cartridge filters use two forms of depth media. The standard depth filter is a self-supporting tube made using a polymer, most often polypropylene, and forming the tube using the melt-blown or nano-spun process. The other form of cartridge depth filter uses pleated flat sheet media, most often made with polypropylene or fiberglass.
Standard depth filters will capture a range of particle sizes through the thickness of the media. Pleated media filters have the advantage of a large surface area that can hold a higher quantity of particles on that surface than the standard depth filters.
In pleated depth filters, polypropylene is the most widely used material for water and chemical filtration, but fiberglass has better filter efficiency and generally allows higher flows and throughput than polypropylene in final product prefiltration applications.
Our filter media are available in multiple filter formats for all flow ranges. Disc filters support small scale flows in test and research laboratories. Small capsule filters are available for low flow applications such as bench scale systems or small product development systems. Our large disposable capsule filters and cartridge filters are used for larger flow applications ranging from pilot production to full scale operations.
The table below shows the filter media in cartridge, capsule and disc filter configurations. We also have sanitary housings for filter cartridges. Click on the in the appropriate location to download a data sheet for the filter media and configuration that fits your needs. For a complete list of all Pharmaceutical and Biopharmaceutical filters from Critical Process Filtration, click here.
|Media Code||Filter Media||Filter Grade||Cartridge Data Sheet||Capsule Data Sheet||Disc Filter Data Sheet||Pore Sizes Available (µm)||Features|
|GDMB||Melt-Blown Polypropylene Media||Service||1, 3, 5, 10, 20, 30, 50, 75, 100||Continuously spun bonded polypropylene media for consistent 85% nominal performance|
|NSPD||Nano-spun Polypropylene Media||Service||1, 3, 5, 7, 10, 20, 30, 40, 50||Very high retention efficiency (99%) and high load capacity to protect downstream processes|
|NMMB||Melt-Blown Nylon Media||Service||1, 3, 5, 10, 20, 30, 50, 75, 100||Spun bonded for consistency with broad chemical compatibility|
|PPD||Pleated Polypropylene Depth Media||Pharmaceutical||0.1, 0.22, 0.45, 0.65, 1.0, 3.0, 5.0, 10, 20, 30, 40, 60, 100||100% polypropylene construction for high purity|
|PGD||Pleated Fiberglass Depth Media||Pharmaceutical||0.22, 0.30, 0.45, 0.65, 1.0, 2.0, 3.0, 5.0, 10, 20, 30||High capacity filters for clarification and prefiltration applications|
To estimate the number of filters you will need for your application, use our unique sizing tools.
The filter media used for each process must, of course, be compatible with the fluids used in it. Contact Critical Process Filtration for assistance in determining the compatibility of filter media and support materials with your process.