The History of Membrane Technology
Before talking about the new Pulsar Charged Membrane Filtration, it would b he helpful if we were to look at the history of membrane filtration.
Membrane technology is not a new technology in itself. Membrane technology includes reverse osmosis (RO), Nano filtration (NF), Ultrafiltration (UF), and Microfiltration (MF). Absolute rated particulate filters also have one thing in common in that they all rely to some degree on media pore size. In cases, where the pores within the media structure develop an integrity breach or if a breach of the vessel seal takes place, the results can be high levels of microbial contaminants bypassing and the filter material as well as releasing contaminants to enter the clean water system! These high levels of microbes can be catastrophic.
There are many RO, NF, UF & MF filtration manufacturers making microbial claims for bacteria, virus and cyst reduction. Such reduction is normally expressed as a percentage or log reduction value (LRV) for the membrane (spiral, hollow fiber or pleated designs). Pleated particulate filters with an absolute rating of 0.1 – 1 micron may also make claims for microbial reduction.
However, the filter choices and performance often depends upon on the seal integrity within the filter vessel. Double Open End (DOE) or Single Open End (SOE) gasket cartridges on some brands of cartridges may have very high efficiency capability but their reliance on a “knife” or pressure seal may not maintain appositive seal sufficient to stop the migration of microbial contaminants due to pressure shifting or pulsations changes from varying flow rates, which can break the seal! Without a proper seal, microbial contamination is likely to occur right from the start. Cartridges using a knife or pressure seal do not have the tolerances sufficient to act as a microbial barrier.
Filter cartridges with a double O-ring seal such as a 222 or 226 (or similar design) that fit into a receiver, within the element vessel, and that provides an O-ring compression necessary to prevent by-pass are the type of filters that should be used.
Integrity of the Cartridge Itself
Now we come to another piece of the puzzle, the integrity of the membrane or particulate filter elements /cartridges. Virus size can be <0.02 um and if the membrane or filter element is not integral all is for naught as microorganism by-pass will surely result. NSF/ANSI Standards 42/61 are for material safety/structural integrity and they do not verify the membrane /element/cartridge are integral. NSF/ANSI Standards 42/61 will assure you that the product material is not imparting anything into the water, and is approved for drinking water treatment units. These Standards are for filtration efficiency issues. Even NSF P231 and P248 protocols, which test for microbial efficiency, are not testing integrity of the elements. NSF is now promoting their latest standard for municipal treatment technology for drinking water NSF/ANSI 419 Public Drinking Water Equipment Performance – Filtration.
Once again it is an efficiency driven standard for microbial LRV but not integrity verification of the elements/cartridges. Why should we be concerned about the integrity of the filter? The same reason that Public water supplies will not give virus LRV credits to membranes without requiring a continuous integrity verification of the membrane/cartridges for every module typically every 15 minutes. Since this technology is not killing the organisms but merely filtering them, Regulatory Agencies are well aware that if any breach of integrity occurs
Public Water Systems are risking their customer’s health and well being. Death could even result for those having low immune deficiencies who receive a high dose of microbes from a possible breach in the element/cartridge or vessel designs.
Disinfection Technology Preferences
Chorine, Chloramine, Chloride Dioxide and high Dose UV (186mJ) are the preferred methods of disinfection preference in municipal markets. UV and Ozone are routinely used for bottled water and the food and beverage industries. Disinfection per EPA and State Regulations is defined as one or multiple treatment processes combined to provide a validated >= 4 LRV reduction of Bacteria, Virus and Protozoan cyst.
Therefore, anywhere that water is used for drinking, misting, cooling, washing vegetables or other potable water applications, one must be aware that if the water is not properly filtered, microbial contamination can cause food spoilage, cause illness, and liability for those selling, installing and using these devices. Therefore one must be certain that any filtration devices has technology capable of providing the Log Reduction Values appropriate for the application.
Advancements in Electro-Adsorptive Technology
Electro-adsorptive technology is now commercially available that does not rely on pore size exclusion for high levels of microbial reduction and does not release the retained contaminants in an event of an integrity breach. The electro-positive charge captures/retains contaminants throughout the depth of the pore structure. This method reduces microbes via adsorption + mechanical filtration not simply pore size exclusion.
The electro-adsorptive charge provides a net adsorption efficiency of ~.002 um and mechanically with a mean pore size of approximately 1.2 microns. The charge field removes the negatively charged, submicron particles while larger particles are captured within the fiber structure of the media. This method reduces virus by > 4 LRV with a mechanical mean pore size of approximately 1.2 microns.
Electro-adsorption provides “retention” of the organisms through these charged structures within the media and small integrity breaches, which may occur, does not produce a catastrophic release of organisms. Mechanical pore dependent membranes and filters do not enjoy this benefit.
This filter media has over 400 layers of pore depth created by a wet laid non-woven manufacturing process. This results in a media having a torturous flow pattern, high flow rates at low pressure drop. The charge field results in a high initial removal efficiency as well as high loading capacity. This results in high energy saving. The CMF technology approaches Nano-filtration that requires very high psi inlet pressures.
This media has been sold commercially for years with great results. When used with appropriate and properly prefiltration for particulates provides sufficient life cycles between cartridge changes to satisfy all involved. With a cost comparable to MF and much less than RO/NF/UF membranes making it very competitive in the market place.
While the media performance is excellent it still requires good manufacturing practices and the integrity of the finished product is just as critical as membranes. This media requires manufacturing knowledge and experience as it can be difficult to pleat due to its 1 mm thickness and composite structure. A quality control procedure with 100% NDPT (Non Destructive Performance Test) or reverse bubble testing in alcohol solution is required at the production facility for every cartridge to insure the integrity.
Disposal Issues![Agion]()
Spent elements and cartridges that remove microbes become a bio hazard and without an antimicrobial additive to control these microbes cannot be disposed of as normal waste. This issue is most often overlooked and the elements and cartridges are typically disposed of in the trash. The Pulsar CMF filter is manufactured from a naturally occurring element called boehmite, which has no known Health Side Effects. The filter is impregnated with Agion® Silver Zeolite Technology which protects filter and reduces tastes and odors from microbes.
Conclusion
Pulsar Charged Membrane Filtration or CMF is a disruptive technology. It is one that displaces an established technology and shakes up the industry or a ground-breaking product that creates a completely new industry. When the PC replaced the typewriter, it forever changed the way we work and communicate. Cell phones were “disruptive technology” because it allowed us to communicate from almost anywhere and the Pulsar Charged Membrane Filter System is “disruptive technology” in that a filter system can now remove the following contaminants:
- Bacteria (99.8%)
- Iron
- Virus (90-92%)
- Copper
- Cysts
- Lead
- Tannin
- Chromium VI
- Endotoxins (96%)
- Selenium
- Legeonella (99.9%)
- Tannic Acid
- Silica
- Humic Acid
- Heavy Metals
- Cryptosporidium
- Fulvic Acids
Charged Membrane Filtration or CMF is manufactured with Nano Alumina Fibers that have a Zeta potential of 51 millivolts. A CMF cartridge retains bacteria, virus, cryptosporidium oocysts and even tannin with its strong Zeta Potential. To removes cysts and bacteria, the flow rate is 10 GPM, but if you are removing tannin, the flow is 15 GPM.
How It Is Made
Unlike mechanical filters which rely on “pore size” the Charged Membrane Technology literally “secures” the contaminant. It is “absorbed” in a very real way. The filters have a long life and are easily replaceable.
Health and Safety
The CMF media is manufactured from a naturally occurring element called boehmite, which has no known Health Side Effects. In fact, boehmite has long been used as an additive to food products and digestive analgesics. Additionally, it has passed testing for NSF/ANSI Standard 42 and 61 for potable water and USP Class VI testing and endotoxin testing.
CMF media is engineered this 51 millivolt charge cover the entire volume and depth of the media. A CMF filter accomplished submicron filtration with a “charge” rather than “pore size” filtration, which allows for virtually zero pressure drop and high flow rates. If you compare the Pulsar CMF to “ultrafiltration” membranes, you will find dramatically higher flow rates with less pressure drop.