Introduction to ErtelAlsop Pak® Lenticular Filters
For industries requiring high-performance depth filtration without the labor intensity of traditional systems, ErtelAlsop Pak® Lenticular Filters represent a premier solution. As a distributor/OEM for leading filtration brands, Purecowater provides these advanced lenticular cartridges to tackle complex solid and liquid filtration challenges.
Originally invented by Alsop Engineering in the 1940s, the lenticular format has evolved into a standard for efficiency. The Pak® cartridge design positions depth filter media in a sealed, stacked-disk configuration, offering the superior retention of depth sheets with the convenience of a cartridge.

How Lenticular Filtration Works
The ErtelAlsop Pak® is assembled from varying numbers of filter cells stacked vertically. Each cell consists of a pair of depth filter media sheets (such as MicroMedia®, AlphaMedia®, or MicroClear®) with edges sealed via a patented injection-molding process using polypropylene [ertelalsop.com].
This “double convex lens” shape allows liquid to flow from the outside of the cartridge, through the media, and into the central core. The result is a totally enclosed system that eliminates leakage and external contamination—a significant upgrade over traditional plate and frame filter presses.
Key Features and Specifications
The Pak® depth filter cartridges are versatile, designed to fit a wide range of housings and applications. Below are the core technical specifications suitable for industrial and sanitary use.
| Feature | Specification Details |
|---|---|
| Diameters | 12 inch (30.5 cm) and 16 inch (40.6 cm) |
| Configuration | 5 to 18 stacked lenticular filter cells per module [ertelalsop.com] |
| Micron Retention | Nominal ratings from 0.25 to 15 microns |
| Media Types | MicroMedia® (Cellulose/Perlite/DE), AlphaMedia® (All Cellulose), MicroClear® (Activated Carbon) |
| Construction | Flat Gasket or Double O-Ring; Polypropylene Core |
Operational Benefits
1. High Solids Loading & Retention
The complex matrix of fibers and particles in the filter media provides a high solids loading capacity. This depth filtration mechanism is highly efficient for particle retention, haze removal, and product polishing [ertelalsop.com].
2. Operator Friendly & Closed System
Unlike plate and frame filters, which can drip and require laborious cleaning, lenticular housings are totally enclosed. This containment prevents product loss and protects operators from exposure to process fluids. The “Lock and Load” system available on Horizontal housings further simplifies change-outs [ertelalsop.com].
3. Scalability
Since Pak® modules use the same media as laboratory-scale discs and full-scale filter sheets, scaling up from R&D to full production is seamless. Process specifications translate directly across formats [ertelalsop.com].
Housing Configurations
Purecowater offers various housing orientations to suit your facility’s layout and piping requirements.
- Vertical Industrial Housings: Ideal for general chemical applications. Available in Carbon Steel, 304, or 316L Stainless Steel. Capable of flow rates up to 375 liters per minute per housing [ertelalsop.com].
- Horizontal Housings: Designed for easy loading at waist height, eliminating the need for overhead hoists. These reduce downtime and are practically maintenance-free [ertelalsop.com].
- Sanitary Housings: For pharmaceutical and food & beverage applications requiring high polish and sanitary fittings.
Applications
ErtelAlsop Pak® Cartridges are utilized across a diverse spectrum of industries:
- Pharmaceuticals: API solvent filtration, catalyst removal.
- Food & Beverage: Haze removal, intense polishing of spirits and syrups.
- Chemicals: Silicone production, specialty chemical filtration.
- Utilities: Dielectric fluid treatment and transformer oil purification (AquaKv-Pak®) [ertelalsop.com].
Start Your Filtration Project
Purecowater can help you select the correct media grade and housing configuration for your specific stream. Whether upgrading from a press or designing a new line, our team is ready to assist.