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Critical to the absolute purity of the finished product is filtration at every stage, including prefiltration of raw water as it enters the process. Pall has addressed the need for an economical and reliable particulate filter systems designed for the following applications.

• Removal of resin fines
• Protection of a reverse osmosis (RO) filter
• Removal of carbon fines
• Protection of a final filter
• Particulate removal in bottle washing operations

The filter locations and recommendations are provided below (bottle washing not depicted)

Application	Filter medium	Absolute Rating (micron)
Supply water coarse prefiltration and final filter protection	Profile® with Ultipleat® configuration	10 20 40
Supply water fine prefiltration and final filter protection	Ultipor® GF Plus Ultipor® (resin bonded glass fiber) with Ultipleat High Flow configuration	1 2 2
Carbon fines removal	Profile with Ultipleat configuration Profile	10 20 1 5
Resin fines removal	Profile with Ultipleat configuration Profile	4.5 1 5
Protection of RO membrane	Profile with Ultipleat configuration Profile	4.5 1 5

Product Information

• Profile filters
• Ultipor GF Plus Filters
• Filters with Ultipleat configuration
• High Flow filters with Ultipleat Construction

Profile filters

Profile filters are all polypropylene depth filters. The membrane has an absolute-rated downstream section and a continuously graded pore size upstream section, which increases the service life many-fold, resulting in an economical operation. The fibers in the Profile membrane are continuous and no binder resin or glues are used. The fibers are "bonded" by an intertwining technology and as a result of this manufacturing technique, Pall Profile membrane material and trapped contaminants do not migrate to the downstream (filtered) water.

Profile filters are available in a variety of styles to meet the requirements of the application. Filters with absolute micron ratings from 0.5 to 120 micron are available.

Benefits of Pall Profile Products

• Pall Profile depth filters have a constant pore size resulting in reliable filtration with no unloading and no media migration
• Pall Profile depth filters have been designed with a constant density filter medium with a high voids volume, resulting in high dirt loading capacity, maximum throughputs, and long service life
• Pall Profile depth filters contain no resins, binders, surfactants or potting compounds to ensure a continuously clean effluent
• Economic filtration is achieved using Profile filters because they have a longer service life than conventional depth filters and require less frequent change-out
• Absolute removal of fine particles ensures visual clarity
• In carbonated fluids, absolute removal of fine particles maximizes carbonation
• Turbidity specifications can be consistently met by using Pall Profile filters

Ultipor GF Plus filters

Ultipor GF Plus prefilters have a pleated high area construction for long service life. The glass fiber medium has a binder resin, which imparts a positive zeta potential for enhanced particulate removal. The resin also binds the fibers to an inert polyester substrate to produce a rugged composite medium. The Ultipor GF Plus cartridges can efficiently remove submicroscopic haze. Ultipor GF Plus filters with absolute micron ratings from 1 to 40 micron are available.

Benefits of Pall Ultipor GF Plus filters

• Pall Ultipor GF Plus filters have positively charged media that can provide removal efficiency enhanced by retention of particles smaller than the removal rating of the medium
• The Ultipor GF Plus filter can remove negatively charged particles (pyrogens) from water
• A wide range of absolute micron ratings are available to meet specific application requirements
• The Ultipor GF Plus filter often used in this application has a graded pore structure for up to 3X the dirt holding capacity over a uniform pore structure design. In a graded pore structure design the contaminant is captured in the outer 60% of the filter, whereas in a uniform pore structure design the contaminant is captured in the outer 15% of the filter

Filters with Ultipleat configuration

Pall Filters with Ultipleat configuration

Profile filters with Ultipleat configuration use continuous Profile membrane in a proprietary cresent-shaped pleat structure. This design is also available for Pall Ultipor GF Plus filters. A patented spiral wrap is attached to each pleat to allow for uniform flow through each pleat. The benefit of the Ultipleat configuration is a reduced pressure drop (as low as one-fifteenth that of conventional depth filters) and higher flow rate which results in unsurpassed filter service life.

Benefits of Pall Filters with Ultipleat Construction

• Uniform flow distribution with Ultipleat construction, which can provide a longer service life
• Patented spiral wrap bonded to each pleat, maintains a uniform flow through pleats and prevents pleat collapse and bunching.
• Longer life than many pleated polypropylene membrane filters, resulting in lower costs and reduced change-outs
• Higher flow rate and lower differential pressure than pleated and depth media capacity

High Flow filters with Ultipleat Construction

Pall has addressed the need for an economic and reliable particulate filter system designed for high flow applications—a solution that eliminates having to settle for the traditional systems, bag filters or cartridge filter which truly do not meet all process requirements. Pall Profile and Ultipor (resin bonded glass fiber) filters are available in an Ultipleat High Flow filter configuration. These products combine the benefits of the membrane (resin bonded glass fiber or Profile) and the Ultipleat crescent shaped pleat geometry into a design that allows for flows up to 500 GPM per membrane cartridge.

Ultipleat High Flow filters utilize a 6-inch diameter and a 40 - 60 inch length to maximize the ratio between surface area and cross sectional area and to minimize core pressure drop. The flow direction is in to out so that contaminants can be collected inside the filter for easy disposal. The filters are coreless, with an all plastic construction, to minimize waste disposal costs. Micron ratings from 2 to 20 microns are available.

The Ultipleat High Flow filter design allows for a smaller footprint with fewer filters to change-out.

Benefits of Pall Filters with High Flow Ultipleat Construction

• Reduced capital costs
• Reduced element replacement costs
• Reduced maintenance time
• Reduced waste volume
• Lower clean pressure drop
• Ease of service
• Smaller footprint
• Higher fill rates
• Lower product hold-up volume

The regulations regarding microbial issues for bottled water are different throughout the world. Pall Corporation has developed filtration technology that meets the requirements for each geography. This section contains information for water bottlers that follow the US regulations.

Pall offers a wide range of final filters to ensure microbial stabilization prior to bottling. Pall provides 0.45 micron and 0.2 micron filters for removal of bacteria, molds, or other fine contaminants in water for those bottlers that desire a higher level of protection.

Sub-micron filters

A final sub-micron filtration step for microbial stabilization provides an additional level of contaminant removal security. Final filtration is performed before packaging to microbially stabilize the water by removing bacteria and molds and by providing a final polishing filtration.

Pall Ultipor filters with N₆₆ membrane are used routinely to provide biologically stable beverage products. Pall Ultipor filter cartridges with N₆₆ membrane are specifically engineered for microbial stabilization (0.45 or 0.65 micron rating) or sterilization (0.2 micron rating). They incorporate versatile Nylon 6,6 membranes that are high area pleated into single open ended cartridges for use in sanitary filter housings and have been designed to provide reliable economical and efficient microbial stabilization or sterilization. Integrity testable Ultipor filter cartridges with N₆₆ membrane are available with 0.2, 0.45 and 0.65 micron microbial ratings. Fully manufactured 0.2 micron filter assemblies are validated by liquid challenge with Brevundimonas diminuta at 10⁷/cm² filter area and are 100% integrity tested. Typical titre reductions for 0.45 and 0.65 micron filters are provided in the table below.

Micron rating	Test organism	Typical titre reduction
0.45	Serratia marcescens	108
0.65	Pediococcus damnosus	106

Pall also offers integrity testable Supor^® filters with a new polyethersulfone (PES) membrane and Fluorodyne^® filters with a polyvinylidiene fluoride (PVDF) membrane for microbial stabilization or sterilization. The variety of membrane types ensures that we can provide a product that will work with the required cleaning regimen.

Additionally for a more economical filtration process, prefilters are often used to remove particulate materials and protect the final filters to ensure a long service life. Pall offers several prefilter options so that the requirements for a specific bottled water operation can be met. Bottled Water prefilters include the Profile family of filters and Ultipor GF Plus and Ultipor filter cartridges.

Benefits of Pall final filters:

• Total filtration systems are provided to meet process economics and product quality requirements
• Integrity testable filters to assure performance
• Inherently tough membranes designed to withstand extreme operating conditions
• High voids volume for low clean differential pressure and long on-stream life
• Fixed pore structure ensures that there is no unloading of trapped contaminants
• Complete line of membrane filters (Nylon, PES or PVDF) to meet specific product and process requirements
• Products available for microbial stabilization or sterilization to meet application requirements
• Intrinsically water-wettable
• Resin and surfactant-free
• Flushed with high purity water before shipment to provide consistent product cleanliness
• Broad solvent compatibility
• High area for long life
• Hot water sanitizable
• Repeatedly steamable in situ
• Individually serialized for traceability
• Manufactured by Pall in a controlled environment
• Integrity tested before release

 

The regulations regarding microbial issues for bottled water are currently different in Europe and the USA. Pall Corporation has developed filtration technology that meets the requirements for each area. This section contains information for water bottlers that follow the EU regulations.

EU directive for mineral natural waters

The European regulation concerning the exploitation and commercialization of mineral natural waters is European directive 80/777/EEC, modified by the directive 96/70/EC. The directive prohibits any treatment that may modify the microbiological content of the water.

Pall Corporation has filtration specialists available to help Mineral Water bottlers protect the natural quality of the Mineral Water from external potential contamination in respect of the existing directive.

The CDC and EPA recommendation

On June 15, 1995 the CDC (Center for Disease Control) issued a press advisory for people with weakened immune systems, which was supported by the EPA.

".....Among the most effective point-of-use filters are those labeled reverse osmosis or "Absolute" one micron filters or those certified by the National Sanitation Foundation* International under Standard 53 for "Cyst Removal."

"The nominal one micron filter may not reliably remove Cryptosporidium."

* - The name "National Sanitation Foundation" was changed to NSF International in 1991

Water bottlers can add CO₂ to their water to produce a sparkling product. Water bottlers can add CO₂ to their water to produce a sparkling product. Microorganisms can be present in the CO₂ piping and can lead to contamination of the product. Sterile filtration can be employed in these applications to prevent the introduction of microbial contaminants, such as molds and bacteria, via the CO₂.

Pall Emflon PFR Filters

Microbial contaminants can enter the water storage tanks if the tank is not properly protected from the environment. This can lead to contamination of the batch. Pall Emflon PFR filters can be used as vent filters to protect the water tanks and holding tanks from contamination by molds, bacteria and other microbial contaminants.

Emflon PFR filters, featuring two layers of Pall 0.2 micron polytetrafluoroethylene (PTFE) membrane, are designed to protect a sterile tank from the ingress of bacteria, molds and particles, even in the presence of humidity and moisture. All other filter components are made of oxidation reistant polypropylene. Fully manufactured assemblies are validated by stringent liquid challenge with Brevundimonas diminuta at 10⁷/cm² filter area and are 100% integrity tested. Emflon PFR filters are integrity testable by Water Intrusion and Forward Flow tests.

If required, the Emflon PFR can be protected by a Pall prefilter to ensure long life of the final filter.

To ensure microbiological stability in the bottle or can, it is necessary to guarantee the quality of services such as water, steam and gases that are either in direct or indirect contact with the product to be bottled or canned.

Examples include the pressurized gas used in isobaric filling machines, the water used for cleaning the facility and the bottles, as well as for rinsing and sanitizing the filtration system, and the steam used for sterilization. All of these fluids can contain a variety of contaminants, which, if not removed, can cause costly recontamination. Pall’s solutions include Emflon PFR filters for gas sterilization, Ultipor GF Plus and the Profile family of filters for the filtration of cleaning water, and PSS filters for the removal of solid contaminants from the steam used for sterilization.

Complementing Pall’s wide array of filtration systems is the Pall Life Sciences line of disposable and reusable funnels, membrane media and accessories. Environmental and industrial microbiologists can save time and money as well as ensure accurate results with the Pall Life Sciences line which has been optimized for testing drinking water quality. For example, the Pall Life Sciences Envirochek Sampling Capsule is fully validated for use in US EPA method 1622 and 1623 for analysis of water-borne contaminants such as Cryptosporidium and Giardia.

Click here to visit Pall Life Sciences