POREX® Radial Cartridge

Porex Radial Cartridge Filter

Application: Oral Dosage Filtration

Target Market: Pharmaceutical

Application Description
A variety of oral dosage products (mouthwashes, cough medicine, intestinal medicines, etc.) manufactured by pharmaceutical companies are either terminally sterilized by heat or use preservatives to maintain their biological stability. Although regulated by the FDA, these products still must be filtered to provide a visually acceptable product. There are no requirements for submicron filtration since the stomach and intestinal wall act as an effective barrier to non-viable particulate and the product is provided free of bacteria via non-filtration methods. Therefore, particulate filtration in the 1 to 10 micron range is usually sufficient.

Porous Polyethylene

Types of Filters Used
The most common filters used in oral dosage filtration applications are depth or pleated polypropylene cartridges with ratings from 1 to 40 microns.


Purpose of Filtration
The purpose of filtration is to remove visible or smaller particulate that could make the product unacceptable to the consumer.

Common Filtration-Related Problems

  • Current System Design – Not originally designed for backflushing, but most can be adapted
  • Ineffective Cleaning – Differential pressure too high prior to backflush, multiple layer filter, inaccessible pleats, poor reverse flow, insufficient duration
  • Backflush Solids – Volume, wetness, transportation, hazardous materials
  • On Restart, Filters Plug Quickly – Ineffective backflush did not get contaminant out of the system
  • Operator Intensity or Dependence – Automate the system
  • Economics Visualization – Field trial with pilot (side stream or existing system)
  • Cartridges Dislodge from Seal Plate – Install a hold down device or locking mechanism to keep cartridges in place


Sintered High-Density or Ultra-High Molecular Weight Polyethylene
Rigid, Omni-Directional Pore Structure
  • Absolute Ratings
  • Consistent pore structure minimizes performance changes caused by differential pressure
  • Reproducible performance
  • Narrow Pore Size Distribution
  • Highly-effective surface filtration for particles larger than the filter pore size rating
  • Allows for effective cleaning, backwash and reuse
  • Thermally-Bonded
  • Sintered omni-directional pore structure
  • No media migration, bypass or unloading from 5 to 100 microns
  • Excellent Chemical and Thermal Compatibility
  • High chemical resistance of HDPE and UHMWPE
  • Completely incineratable with a high BTU output
  • No chemical degradation resulting in bypass or contamination of the process fluid
  • No incineration residue
Unique, Molded Radial Design
  • High Surface Area
  • Low pressure drop and higher flow rate
  • Increased life or fewer filters results in lower filtration costs
  • Open Channels
  • Easy access to filtration area
  • Effective filtration and cleaning
  • Single-Layer Structural Media
  • Eliminates unnecessary support materials
  • Improves backwash and cleanability
  • Rigid, One-Piece Construction
  • Multiple diameters, lengths and end configurations
  • Easily adapts to existing filtration systems

Performance Comparison

Rigid, Omni-Directional Pore Structure

POREX Radial
Cartridge Filter vs
Micron Rating =/- =/-
Absolute Filtration =/+ =/+
Surface Retention =/+ +
Classification Filtration =/+ +
Sintered Process + +
Polyolefin Material = =
Chemical Compatibility = =
Thermal Compatibility = =

Unique, Molded Radial Design

POREX Radial
Cartridge Filter vs
Backflushable + +
Surface Area + -
Molded Construction + +
Rigid Structure =/+ +
Open Pleats + +
Disposal Cost + +
Performance Priced + +
Single Material = =/+
Vessel Seal = =
Housing Fit = =
Symbol Key: = Porex equivalent | + Porex advantage | - Porex potential limitation