How to correctly select the ideal membrane filter cartridge?

Filtration is the process of separating liquids or gases, where the feed stream is partitioned into permeate and retentate by passing through a specific medium. Various filtration types exist, with one classification based on the filtration medium, such as membrane filtration.

With a plethora of filter options available, it’s essential to understand the key factors that influence the choice of a suitable membrane filter cartridge. In this guide, we will explore the considerations that should guide your decision-making process.

What is Membrane Filter Cartridge?

Membrane cartridge filters with an asymmetric pore structure are primarily designed for applications requiring high flow rates and high particle suspension. Membrane filters are available in various sizes and shapes, including cartridges, capsules, and disks. Brother Filtration provides a broad range of pleated membrane cartridges to meet different filtration needs.

Membrane filter cartridges work by utilizing a porous membrane material that acts as a physical barrier, capturing particles of a specific size or larger. These membranes are available in different pore sizes, typically ranging from 0.1 to 10 microns, allowing for customization based on the specific filtration requirements.

Membrane filter cartridges are highly efficient filtration devices that are widely used in various industries for diverse applications. These cartridges feature a membrane as the primary filtration medium, which allows for the precise removal of contaminants from fluids.

Comparing Absolute and Nominal Filtration Types

Filters are categorized based on their structure and filtration method, namely “absolute” and “nominal”. The nominal type, also referred to as depth filters, consists of randomly tangled microfibers. When the liquid passes through these filters, particles are retained by adhering to the fibers. In contrast, absolute filters are generally made of synthetic resin films or membranes with micro-sized pores that trap particles larger than a specific size.

Depth filters are influenced by process conditions like operating pressure or contaminant concentration, so it is mainly used as pre-filters. In contrast, membrane filters serves as absolute filtration retaining particles above a defined rating. Take bottled water, for example. Its production process requires multiple filtration steps. The nominal filter is used to remove larger particles beforehand to reduce clogging of the final filter. The absolute filter is used before packaging to ensure the removal of harmful substances and contaminants in bottled water.

Material Selection for Membrane Filters

Membrane filtration serves as a sterilization method in situations where heat sterilization is impractical. Given the bacterial size range of 0.3um to 0.5um, sterile membrane filters typically have a pore size of 0.2um, effectively removing contaminating microorganisms.

The material properties of the membrane and the distribution of pores will affect the performance of the membrane filter, which is why the choice of membrane type is particularly important. Our commonly used membrane materials include polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and nylon.

When selecting a filter membrane, the primary consideration is its chemical compatibility. This involves assessing its resistance to substances such as acid, alkali, and organic solvents. The filter membrane, available in various materials, is utilized for filtering different liquids, with selection based on chemical compatibility.

• PTFE filter membranes are preferred in the presence of strong acids or alkalis.
• PES membranes have acid and alkaline resistance, low extractables, thermal stability, and low protein binding.
• Microporous Glass Fiber Membrane Filters serve as coarse filtration, acting as pre-filter materials unsuitable for filtering hydrofluoric acid.
• In the presence of organic solvents, options include nylon or PTFE hydrophilicfilter membranes.
• For applications without acid or alkali, choices encompass mixed cellulose ester, polycarbonate, or PVDF filter membranes.
• PVDF membranes are even suitable for weak acids or bases.
• PTFE membranes boast compatibility with a wide range of solvents, acids, and alkalis.
• PP membranes exhibit stable chemical performance and resistance to acid and alkali.
• Nylon 66 membranes are compatible with most organic and water-based solvents but are not recommended for use with strong acids.

Uses of Membrane Filters

Pleated cartridge membrane filters are employed in a variety of filtration processes, encompassing food and beverage applications (such as wine and bottled water), purification of water and chemicals in semiconductor and electronics manufacturing, as well as the filtration of industrial and process water in pharmaceuticals and other industries.

Food and Beverage Processing: Membrane filter cartridges are utilized to filter and clarify liquids in the production of beverages like beer, wine, and bottled water, as well as dairy products.

Biotechnology: In biotechnology applications, membrane filters are employed for the filtration of biological products, including amino acids and enzymes.

Pharmaceutical Manufacturing: Membrane filter cartridges play a crucial role in pharmaceutical processes, particularly in filtering process water and obtaining pure water for pharmaceutical formulations.

Electronics and Semiconductor Manufacturing: These filters are essential in the electronics and semiconductor industry for purifying industrial water and producing high-purity water used in manufacturing processes.

Chemical Processing: Membrane filter cartridges are used to filter and separate chemicals in various industrial processes, ensuring product quality and consistency.

Conclusion

Using membrane filtration can reduce operating costs and improve product quality. Membrane filtration systems are relatively simple and more economical. Membrane filters leave no residue during installation, reducing disposal costs. High-quality membrane filters significantly improve product quality, allowing manufacturers to produce safer and more stable products.

If you have any concerns about the selection of membrane pleated filtration filters, please feel free to contact us. Brother Filtration will provide you with the most suitable membrane filtration solutions for your site.