When it comes to depth filtration, few solutions offer the versatility, reliability, and scalability of the ErtelAlsop Pak® Lenticular Filters. Designed to replace messy plate and frame filter presses without sacrificing filtration area or quality, these cartridge modules—commonly known as "Paks"—have become the workhorse for industries ranging from pharmaceuticals to botanical extraction and food and beverage.
At Purecowater, we specialize in solving complex solid and liquid filtration challenges. As a distributor and OEM partner, we provide high-performance solutions like the ErtelAlsop Pak® series to streamline your process.
What is a Lenticular Filter?
Lenticular filters utilize a stacked disc design. A "Pak" is assembled from multiple individual cells stacked vertically. Each cell consists of a pair of depth filter media sheets sealed around the edges. This construction resembles a series of double convex lenses (hence the term "lenticular").
This design allows operators to house a massive amount of filtration surface area inside a compact, sealed stainless steel housing. Unlike traditional plate and frame presses, lenticular Paks prevent leakage and atmospheric exposure, making them ideal for critical applications involving solvents, hazardous fluids, or high-value products.
Key Features and Benefits
- High Solids Loading: The depth media structure traps particles not just on the surface but throughout the thickness of the media, allowing for greater retention capacity.
- Scalability: Available in industry-standard 12-inch (1.8 m² area approx.) and 16-inch (3.4 m² area approx.) diameters.
- Zero Bypass Construction: Options like the Bio-Pak® feature double O-ring seals to ensure total containment, critical for pharmaceutical sterility.
- Simplified Maintenance: Changeouts take minutes rather than hours compared to plate and frame filters.
Product Configurations and Media Types
ErtelAlsop offers distinct formulations tailored to specific process requirements. Choosing the right media is essential for optimizing flow rates and filtrate clarity.
| Series Name | Primary Media Composition | Best Application |
|---|---|---|
| Zeta-Pak® | Cellulose, Diatomaceous Earth (DE), Wet Strength Resin | General Purpose: Botanical extracts, haze removal, chemicals. Offers positive Zeta Potential for ultra-fine particle removal [clearsolutionscorp.com]. |
| Disc-Pak® | 100% Cellulose (AlphaMedia) | Viscous Fluids: Dielectric oils, syrups, fragrances. Ideal where no mineral/DE extractables are desired [ertelalsop.com]. |
| Bio-Pak® | Pharmaceutical Grade Media | Critical/Pharma: Blood fractionation, cell culture media. Features double O-ring seal to prevent bypass. |
| ZetaDri-Pak® | Water Absorbing Cellulose | Moisture Removal: Removes free and emulsified water from transformer oils and silicones. |
Technical Specifications
Understanding the specs is crucial for fitting these modules into your existing housings or planning a new skid design.
| Diameters | 12 inch (305 mm) / 16 inch (406 mm) |
| Micron Ratings | 0.25 µm – 15 µm (Nominal) |
| End Cap Configurations | Flat Gasket or Double O-Ring (222/226 style equivalent) |
| Core Material | Polypropylene (Standard) or Stainless Steel Straps |
| Gasket Materials | EPDM, Viton, Buna-N, Silicone, Teflon Encapsulated |
| Cell Count | Typically 5 to 18 cells per module (16 cells is standard) |
Applications
The versatility of the Pak® filter allows for its use across a myriad of industries.
- Botanical Extraction: Widely used for winterization and dewaxing. The diatomaceous earth in Zeta-Pak media efficiently captures lipids and waxes while maintaining high flow rates for ethanol or hydrocarbon solvents [clearsolutionscorp.com].
- Food & Beverage: Polishing distilled spirits, clarifying syrups, and haze removal in wines and juices.
- Industrial Oils: The Disc-Pak and ZetaDri-Pak are essential for reconditioning insulating oils and transformer fluids by removing particulate carbon and moisture.
- Pharmaceuticals: Pre-filtration for protection of expensive final membrane filters in biotech processes.
Why Choose ErtelAlsop?
ErtelAlsop has been a leader in depth filtration since the 1920s. Their Micro-Media® formulation charges the media with a positive Zeta Potential, which attracts negatively charged contaminants (like bacteria and endotoxins) that are smaller than the filter’s physical pore size. This electro-kinetic adsorption provides clearer filtrate and superior protection for downstream equipment compared to mechanical sieving alone.
Get the Right Pak for Your Process
Whether you need to remove wax from a botanical concentrate or polish a pharmaceutical intermediate, selecting the correct micron rating and media composition is vital. Purecowater can assist in sizing your housing and selecting the optimal ErtelAlsop modules.