Membrane filtration, as an important filtration technology, has shown its unique function and potential in various fields. The most mainstream membrane filters in the filtration market contain membrane pleated cartridges, capsule filters, nanofiltration membrane filters and so on.

In recent years, the emergence of Lenticular Filters has brought new changes and options to the filtration market. Read this guide as we take you through an in-depth look at Lenticular technology, including how it works, the wide range of applications, the benefits, and key information on selection.

What is a Lenticular Filter?

A Lenticular Filter is a cartridge that utilizes a large surface area and depth filtration to maximize the retention of solid contaminants. Its main feature is its organoid construction, which is designed to maximize surface area.

In filtration, “surface area” or “effective filtration area” refers to the total area of fluid that a filter can handle. The surface area can determine the flow rate or the velocity of the fluid through the filter.

The greater the surface area of the filter, the faster it can handle the fluid. For this reason, Lenticular filters are ideally suited for applications where large quantities of fluids with high solids content need to be processed. The number of units in a Lenticular filter element and the space between each unit directly affects the total surface area of the filter.

How do Lenticular Filter work?

First, unfiltered liquid is pushed into the filter housing through the housing’s inlet tube. This is accomplished by applying positive pressure to the inlet vessel using a pump or compressed air.

As the liquid flows into the housing, it surrounds the filter and wraps around each cell. The pressure forces the liquid into the filter media of the filter cell.

As the liquid moves through the depth media, it follows what is called a “zigzag path,” a non-linear route. The liquid must go through numerous zigzags, which depletes the energy of the particles in the liquid, causing them to become “trapped” in the media.

Unlike standard membrane filters, which only trap contaminants on the surface, depth media traps contaminants throughout the entire volume of the media.

Finally, the filtered fluid reaches the center of the cell, where it is introduced into the cartridge and flows down through the outlet pipe of the filter housing.

What are the advantages of Lenticular filtration?

Lenticular filtration is not the only way to remove large areas of heavy solids. For example, a filter press can accomplish the same thing. However, Lenticular filtration has several advantages that make it an ideal alternative to a filter press.

High flow rates

One of the main advantages of Lenticular filters is their increased surface area, which allows for significantly higher flow rates. This feature allows Lenticular filters to process large volumes of product in a short period of time, increasing productivity and filtration efficiency.

Easy to replace and maintain

Lenticular cartridges have a modular design for quick and easy replacement. This reduces downtime for filter replacement. In addition, this design makes the Lenticular cartridge fully CIP (clean-in-place) capable.

Greater Expandability

Another advantage of the modular design of the Lenticular cartridge is the ease of expansion. Lenticular housings are designed to be vertically expandable, so you can increase capacity by adding filter elements to existing housings. Lenticular housings can hold up to 4 filter elements and can be installed vertically or horizontally as needed.

Small footprint

Vertical scaling also means that the footprint of a Lenticular cartridge is very small, regardless of the number of filters it holds. 4-tier housings have the same footprint as a 1-tier light box. In addition, most housings are equipped with mountable feet that can be fitted with casters or skids for easy mobility.

Totally Closed Circuit

Lenticular filters are completely closed-loop. The product can be processed from start to finish, which is especially useful for applications handling hazardous or volatile liquids.

Applications of Lenticular Filtration

Lenticular Filtration is best suited for processing fluids with high solids saturation.

Applications best suited for Lenticular Filtration include:

• Plant extracts
• Food and beverage
• Pharmaceuticals
• Cosmetics
• Industrial

Can Lenticular Filters be reused?

Grating filters can be reused with limited success if stored properly between runs. Proper storage of a raster filter varies depending on the application and the chemistry of the fluid being filtered.

Due to the nature of depth media, cleaning scale filters for reuse can be a challenge. Since depth media retains particles throughout its volume, cleaning the surface of the filter element only slightly extends the life of the filter.

Cleaning the filter with a cleaning solvent, such as ethanol, can also extend the life of the filter, but even if this is done, the benefits are diminishing with each use. Eventually, the filter will need to be replaced.

When do I need to change the Lenticular Filters?

The correct time to change the Lenticular filter depends on the type and purpose of the Lenticular. The process of determining when to change the filter varies depending on whether the filter is being used to remove solids or color.

When removing solids

For Lenticulars used for solids or wax removal, it is usually best to change the filter when the differential pressure reaches approximately 25 psi.

When Removing Color

When using carbon fiber Lenticulars for color removal, the only way to determine when to change the filter is to observe the color of the final product. This can be accomplished by installing a sight glass fitting on the outlet tube of the Lenticular housing.

When the color of the fluid exiting the housing returns to the original green color it was when it entered the housing, it is an indication that the filter needs to be changed.

Understanding Lenticular Filter Element Types

To find the right filter for your needs, you first need to understand the options available.

DIA Lenticular Filter

Sanitek’ DIA Lenticular Filters are composed of cellulose pulp, diatomaceous earth and/or Perlite, and wet strength resin, which charge modifies the media to exhibit a net positive charge referred to as Zeta Potential. This allows for the highly efficient removal of particles smaller than the filter’s nominal rating.

All components are listed in the CFR as generally recognized as safe for contact with food as dictated by 21CFR 176.170. All Sanitek DIA Lenticular Filters formulations can be manufactured in formats to fit your application.

Features and Quality

• High solids loading
• Diatomaceous Earth filter aid
• Zeta-Potential – Positively charged site within the matrix of fibers which attracts negatively charged particles

ACC Lenticular Filter

Sanitek manufactures activated carbon impregnated media in a range of removal ratings and configurations to fit most filter presses and cartridge formats.

This provides standardization of activated carbon treatment in addition to simplicity and ease of handling and operation. Different grades of carbon can be used in the manufacture of Pharmer™ activated carbon filter cartridges to provide specific adsorptive qualities.

Features and Quality

• High solids loading
• Zeta-Potential – Positively charged site within the matrix of fibers which attracts negatively charged particles

Conclusion

You should now have a good understanding of Lenticular Filters and their filtration principles. Perhaps you are considering whether a Lenticular Filters meets your needs.

If you are filtering liquids with large amounts of solids or waxes, large quantities of product to be processed, and limited operating space, be sure to choose a Lenticular Filters that prevents oxidization of the filtered product, meets strict regulatory standards, and is especially suited for volatile solvents.

Sanitek offers a wide range of Lenticular Filters in a variety of materials and types, with filtration ratings to suit your needs, so contact our filtration specialists today for your customized solution.