ErtelAlsop Pak® Lenticular Filters

Advanced Depth Filtration Modules for Critical Applications

Efficient filtration is the backbone of high-purity liquid processing in industries ranging from pharmaceuticals to food and beverage. ErtelAlsop Pak® Lenticular Filters represent a significant evolution in depth filtration technology. Originally innovated by Alsop Engineering in the 1940s, the lenticular format combines the superior filtration performance of depth media with the convenience and sealed hygiene of a cartridge system.

At Purecowater, we provide these robust filtration solutions to tackle complex solid/liquid separation challenges. This guide details the specifications, media options, and operational benefits of the ErtelAlsop Pak® series.

What is a Lenticular Pak® Filter?

A Pak® cartridge (or module) is an assembly of stacked depth filter cells. Each cell consists of two sheets of filter media (such as MicroMedia® or AlphaMedia®) sealed at the edges using a patented polypropylene process. The resulting unit resembles a stack of double convex lenses—hence the term “lenticular.”

Unlike traditional plate and frame filters, which can be labor-intensive and prone to leakage, the lenticular design is totally enclosed within a housing. This ensures minimal product loss, zero external leakage, and a streamlined “Lock and Load” change-out process.

Key Features and Benefits

• Leak-Free Design: The enclosed housing and edge-sealed modules eliminate the drips and leakage often associated with open plate and frame presses.
• Scalability: Available in 12-inch and 16-inch diameters with varying cell counts (5 to 18 cells) to match flow rate and dirt-holding requirements [ertelalsop.com](https://ertelalsop.com/lenticular-pak-cartridges/).
• High Solids Loading: The depth media matrix captures particles throughout the thickness of the pad, not just on the surface, allowing for high retention efficiency and longer service life.
• Versatile Media Options: Modules can be fitted with cellulose, diatomaceous earth (DE), perlite, or activated carbon media to suit specific chemical compatibility and filtration goals.

Media Configurations and Applications

ErtelAlsop offers distinct media formulations to target specific contaminants. Choosing the right “Pak” depends on your process fluid and retention goals.

Series Model	Media Composition	Primary Applications
Zeta-Pak®	Micro-Media® (Cellulose, DE/Perlite, Resin)	The “workhorse” of the line. High zeta potential for catching ultra-fine particles and haze. Ideal for botanical extracts, spirits, and biotech [store.clearsolutionscorp.com](https://store.clearsolutionscorp.com/products/pak-lenticular-filter).
Disc-Pak®	AlphaMedia™ (100% Cellulose)	Contains no inorganic aids (DE/Perlite). Perfect for dielectric oils, syrups, perfumes, and applications where active ingredients must be preserved [clearsolutionscorp.com](https://www.clearsolutionscorp.com/product/disc-pak-lenticular-filter).
Bio-Pak®	Pharmaceutical Grade Media	Designed for critical biological and pharmaceutical applications requiring low extractables.
MicroClear® Pak	Activated Carbon impregnated	Color correction, odor removal, and decolorization without the mess of loose carbon powder.

Technical Specifications

When integrating ErtelAlsop Paks into your system, consider the following technical parameters to ensure compatibility with your existing housings or new installations.

Micron Ratings	Nominal ratings from 0.25 µm to 15 µm [ertelalsop.com](https://ertelalsop.com/lenticular-pak-cartridges/)
Diameters	12-inch (30.5 cm) and 16-inch (40.6 cm)
Cell Count	Standard stacks range from 5 to 18 cells per module
End Cap Configurations	Double O-Ring or Flat Gasket
Gasket Materials	EPDM, Buna-N, Silicone, Viton (Application dependent)
Core Material	Polypropylene rigid core for structural stability

Why Choose Lenticular Over Plate & Frame?

While plate and frame filters are traditional, upgrading to a Lenticular Pak system offers modernization benefits:

1. Reduced Downtime: Changeouts take minutes rather than hours.
2. Operator Safety: The closed system prevents exposure to hazardous fluids or fumes.
3. Sanitary Operation: Easier to clean-in-place (CIP) and steam-in-place (SIP) compared to open presses.