Water Treatment Solutions

Electro-adsorptive technology

Nano-Pak is an electro-adsorptive technology. It uses an electrical charge to remove very small pathogens, like E.coli and Legionella, from the water, while ensuring the healthy minerals that are good for us remain.” This single-source approach to purification is also the most sustainable.

Our water filtration systems purify your water by removing harmful contaminants and impurities, ensuring your water is safe and healthy to drink.

Independent testing has shown filter media to reduce MS2 virus at more than 99.99%. It can reduce a wide range of bacteria at more than 99.9999%, including E. coli, Pseudomonas and Legionella. Removal of three-micron spheres (as a surrogate for cryptosporidium) is more than 99.95% efficient. Media has been proven to reduce certain by species of colloidal metals, hazardous compounds such as PCBs and trace pharmaceuticals including BPA, a known hormone inhibitor.

University testing has shown a combination of electroadsorption and depth filtration to effectively reduce low molecular weight organic acids and polysaccharides from fresh, brackish and salt water. These organic materials are now considered the main cause of fouling for hollow fibre and reverse osmosis membranes.

This technology is indeed unique in its approach to water filtration. The active "ingredient"  is nanoalumina fibers made of the mineral boehmite AlOOH. These fibers have a diameter of 2nm and a length of 200-300nm, with dense electropositive charges that extend up to 1μm from the fiber. With surface areas of up to 500 square meters per gram, a typical pleated cartridge can have more than 10,000 square meters of active surface area.

One of the unique features is its ability to alter the electrical potential by controlling the packing density of the nanoalumina fibers. This potential can range from -32 mV to +32 mV, which affects the filtration and adsorption capabilities of the media. Combining both electrical and mechanical filtration, allowing it to effectively remove or reduce particulates ranging from submicron to nanoscale. The media efficiently removes contaminants below 0.5 μm, including low mass and low-density particulates.

The filter also has the potential for adding functionality through chemical modification or the addition of particulates. This allows for the creation of affinity for specific compounds and the removal of metals such as lead and arsenic. Different nanopowders, such as powdered activated carbon, can be added to enhance the filtration capabilities.

The potential applications in water filtration are vast, with opportunities in both Point of Use (POU) and Point of Entry (POE) filters. It is suitable for potable water, food and beverage, pharmaceutical manufacturing, and commercial water and wastewater treatment.

In terms of health and safety, the materials used  except for the nanoalumina, have been extensively used in the manufacturing of air and water filter media. The nanoalumina itself is composed of boehmite AlOOH, which is abundant in nature and sources are readily available.

In conclusion, this technology offers a unique hybrid filter media that combines electroadhesive nanofibers with mechanical filtration. It provides high loading capacity, fine particle retention, and low pressure drop compared to traditional filter media. Disruptor™ has been proven to effectively remove nano-sized contaminants and has the potential to enhance its capabilities through functionalization and the addition of specific compounds.

It also offers High Flow, a variant of the filter media with a larger pore volume. While the efficiency of High Flow is reduced compared to standard grades, it has a higher capacity for loading colloid, particulate, and organic acids. High Flow can be used as a pre-filter in conjunction with standard  grades for improved performance in turbid waters. It can also be used as a standalone filter when there are high levels of organic contaminants that need to be reduced, such as in the protection of reverse osmosis membranes from biofouling.

The filter also contains powdered activated carbon (PAC) with an average particle size of only eight microns. Activated carbon at this particle size has a very high pore size-to-weight ratio, which produces remarkably high dynamic adsorption. It uses no adhesives or binders to retain the carbon, which means significantly more active sites remain available for adsorption of chlorine, iodine, volatile organic compounds (VOCs), disinfection by-products (DPBs) and organic acids from water.

High Flow is an exciting addition to our Disruptor® family of filter media. High Flow was commercialised in 2013 and is designed with a large pore volume that is not totally covered by the boehmite charge field. This feature reduces the efficiency of the media but increases its capacity for colloid, particulate and organic acid loading.

When High Flow is used as a prefilter to our standard Disruptor® grades in more turbid waters, the life and efficiency of the two layers significantly outperforms a single layer of Disruptor®. High Flow can also be used as a standalone filter when high levels of organic contaminants must be reduced, such as to protect reverse osmosis membranes from biofouling.

Historically, there have been relatively few significant changes in filter media. With its natural electrokinetic potential and the ability to function through both electroadhesion and mechanical entrapment to effectively remove viruses, bacteria and particulates at high flow rates, nanoalumina fibre based technology represents one such change. It is a multifunctional depth filter medium, effective for many water polishing applications. The nanoalumina media can also be used as a support scaffold for a wide range of very fine or nanopowders to impart compound specific adsorbance.

 Electroadhesion utilizes the difference in charge that may exist between a surface (or fiber) and a particle in an aqueous solution, where a charge is built up by the double layer effect.  Most bacteria and most other particles are electronegative in water.  Smaller particles also tend to become more electronegative.  So an electropositive fixed surface would be far more effective at attracting and retaining particles than one that is electronegative.