Stratum® Series

F i l t r a t i o n | S e p a r a t i o n | P u r i f i c a t i o n

ADVANCED MELT BLOWN FILTER CARTRIDGES

Stratum Series Filter Cartridges

The most advanced meltblowing equipment available isused to create Stratum SeriesFilter Cartridges. By tightlycontrolling the manufacturingenvironment and through use oftop-of-the-line microprocessors,we are able to precisely controlthe process conditions toproduce the most reliable,consistently performing meltblown filter on the market today.

Absolute and Nominal Rated

Stratum Series advanced meltblown filter cartridges areavailable in high performancegrades from 0.5 to 75 microns.Whether your process requiresthe highest efficiency 99.9%rated Stratum A Series, or the90% nominal efficiencyStratum C series, you cancount on the most advancedperformance available from amelt blown filter.

Consistent Performance

The state-of-the-art equipmentused to manufacture all StratumSeries filters produces a highlyconsistent product. You cancount on the same performancefrom lot to lot and from batch tobatch in your process. Themicroprocessor controls thetemperature and humidity in theroom and assures that allprocess conditions remain thesame. The result is a consistentfilter and repeatableperformance in your process.

Longer On-stream Life

The key to long on-stream lifein a depth filter is optimizedporosity and pore gradient.In addition the filter must becomprised of micro thin fibers toproduce the finest pores neededto meet the efficiency require-ments. Stratum advanced meltblowing process features a 4-zone construction to provide truedepth filtration characteristicsand long on-stream life. Byachieving just the right amount ofthermal bonding from fiber tofiber, the filter pore structure ismaintained even under variableprocess conditions and asdifferential pressure increases.

Molded Center Core

Rather than compact fibers toform a support structure, likesome common melt blown filters,the Stratum Series filters areconstructed using a proprietarymolded polypropylene centercore called the “Cactus Core”.Not only does this core provideenhanced collapse resistancebut it also eliminates the flowrestriction inherent with acompacted fiber zone. Thesmall stipples on the coresurface, that give the CactusCore its name, also ensuremedia immobilization toprevent fiber shifting andcontaminant unloading.

High Purity Construction

Stratum filters are made with100% virgin polypropylene andare free of surfactants, bindersand adhesives. They aremanufactured in a controlledenvironment to preventcontamination. The chemicallyinert polypropylene assures thatthe Stratum filters can be utilizedin a wide range of applications,including the most critical ofprocesses. Stratum filters areconstructed of FDA listedmaterials and tests prove theymeet the requirements of USPClass VI. Spent filters can beincinerated to trace ash.

Stratum Series

Applications

Chemical/IndustrialBulk and fine chemical filtration, process water, acidfiltration, make-up water, sodium hypochlorite, ink jetinks, coatings, machine coolants, plating solutions,glycol recovery

MicroelectronicsPre-RO filtration, bulk chemical filtration, CMP slurries

WaterProcess, pre-RO, ultrapure water prefilters, wastewater

Food and BeverageBottled water, wine prefiltration, DE trap, resin trap,carbon trap, bottle wash water, flavorings, pre-RO

CosmeticsMouthwash, lotions, fragrances

Pharmaceutical/BiotechUtility water, pre RO, ultrapure water systems

Oil & GasWater flood, natural gas filtration, water disposal,amine regeneration

Stratum Series Filters meet the requirements of the most demanding applications.

Chemical Compatibility

Chemical Class Excellent Good Suggest Testing

Water (ambient)

Organic acids

Inorganic acids

Alkalies

Solvents

Steaming

Oils

This data is provided for informational purposes only and is not intended as a warranty or guarantee. Graver Technologies assumes noresponsibility in connection with use of this data. Consult with Graver for specific chemical resistance information and filter selection.

Smooth surface finish - no loose fibers torelease into process.

Scanning Electron Microscope view of 4 filtration zones (magnification 300x):

Continuous fiberextrusion meltblowing processproduces no shortfibers that canbreak loose.

Most popular cut endstyle. Many commonend caps stylesavailable.

Cactus Core for high collapsestrength and mediaimmobilization.

4 distinct filtration zones for optimum dirtholding capacity and true clarifying filtration.

Outer prefilter zone withcoarsest filtration fibers

Inner prefilter zone Final prefilter zone Final filtration zone withfinest filtration fibers

Features and BenefitsPerformance Benefit

Fine micro porous structurefor high removal efficiencies

Humidity and temperaturecontrolled environment

Consistentconstruction/performancefrom lot to lot

Highly engineeredconstruction

Higher collapse strength

Excellent flow characteristics

Stipples aid in mediaimmobilization

Prefiltration and final filtrationin one

True graded depth filtrationcharacteristics

Excellent chemicalcompatibility

Biologically inert

Filters are safe for use infood, beverage andpharmaceutical applications

Neglible extractables

No foaming

No joiners to reduce mediaarea

Customer Benefit

Precise and highly consistentfiltration efficiency

High yields in yourprocess/reduced defects

Very precise performance

Ability to operate at higherdifferential pressures

Uniform filtration results

No unloading of capturedcontaminant

Lower filtration costs

Long on-stream filter life

Negligible extractables

Use in a wide range ofapplications

Non-toxic filtration for themost critical applications

Rinses up to 18MV-cm

Clean process

Long on-stream life

Stratum Filter Feature

Ultra fine melt blown fibers

Microprocessor controlledprocess

Molded “cactus” center core

4-zone construction

100% pure polypropylenematerials of construction

FDA listed and USP class VIcompliant

Binder, surfactant, andadhesive free

Continuous lengths up to 40”

w w w. g r a v e r t e c h . c o m

String Wound filters

String winding is one of theoldest filter technologies and hasa number of shortcomings. First,the string itself is coated with alubricant or surfactant to makewinding easier. These lubricantsthen rinse off the filter on acontinuous basis when installedin your process. In fact, it is verydifficult to remove it entirely, somost users that value high puritywill avoid this technology.

Also, string wound filters arecomprised of a woven string,containing short fibers that canrelease downstream into yourprocess fluid. These fibers alsotend to be large in diameter,compared to what a meltblowing line can make. Thelarger fibers pack to createinherently larger pores, makingit impossible to achieve fineefficiencies.

Inconsistent and impreciseperformance is a particularlyconcerning issue with stringwound filters. Lab testing of 5micron labeled products revealedtrue 90% removal efficiencies of25 micron or worse.

Molded Depth Filters

Molded depth filters contain asingle size fiber throughout thefilter which results in uniformpores through the filter’s depthand no pore gradient. The resultis that all contaminant collects onthe filter surface instead ofpenetrating into the filter depth.

Thus molded depth filters areessentially low area surface filterswith all dirt collecting on theoutside 0.5 square feet of area(per 10” filter). The lack ofgradient, and resulting surfacecapture of dirt, results in muchlower filter dirt holding capacityand shorter on-stream life cycles.

Other types of molded depthfilters have grooves cut into theouter surface, which generateloose fiber that can migrate intoyour process. The grooves alsoreduce the filter’s depth, leadingto lower dirt holding capacityand lower initial efficiency.

Conventional Melt Blown Filters

The process of making meltblown filters originated in the1970’s and several big namefilter companies continue to sellproducts made on these archaicprocesses. These older lines usea single fiber extruder to create agraded density structure. Theycreate a gradient by tightlypacking the fibers together tocreate smaller pores in the insidezones and more loosely packingthe fibers to make bigger poresin the outside zones.

This is in sharp contrast toadvanced melt blowingprocesses that use multipleextruders to make finer fibersfor inside zones and coarserfibers for outside zones and donot rely on packing density tocreate fine pore structures. In theconventional process, the densely

compacted filtration zone causesreduced flow and dirt holdingcapacity. A wise consumer willbuy melt blown filters with agraded pore structure, notgraded density, for optimumperformance.

Adding further to the flowrestriction, many conventionalmelt blown filters do not use ahard molded center core forstructural support. Instead theycreate a support structure bydensely compacting fibers, whichresults in moderate to severeflow restriction, a loss of usablefiltration area, and lowercollapse strength, especially atelevated temperatures.

Older melt blowing lines alsoare not capable of producingthe ultrafine fibers required forthe finest removal ratings andso performance may be lessthan desired.

Finally, even some of the newermelt blowing lines may notproduce a consistent product.The melt blowing process ishighly sensitive to changes inroom temperature and humidityso should not be run in an openfactory environment. In addition,it is essential to precisely controlthe many process inputs and tomaintain process stability byusing advanced controllers.Only then will the same productresult time after time.

Stratum Series OutperformsCompeting Depth Filter Technologies

Your process requires predictable and highly consistent removal of contaminants. While there aremany types of depth filters available in the market, they do not all deliver the highest performance.Compared to competing technologies, Stratum Series provides the most reliable and advancedperformance available in a depth filter.

For more informationGraver Technologies Customer Service: 1-888-353-0303Technical Support: 1-800-510-0932E-mail us at info@gravertech.comGraver Technologies Europe (UK): +44-1424-777791

All information and recommendations appearing in this bulletin concerning the use of products described herein are based on tests believed to be reliable. However, it is the user’sresponsibility to determine the suitability for his own use of such products. Since the actual use by others is beyond our control, no guarantee, expressed or implied, is made by GraverTechnologies as to the effects of such use or the results to be obtained. Graver Technologies assumes no liability arising out of the use by others of such products. Nor is the informationherein to be construed as absolutely complete, since additional information may be necessary or desirable when particular or exceptional conditions or circumstances exist or because ofapplicable laws or government regulations. Stratum is a trademark of Graver Technologies, LLC.

A member of The Marmon Group – A Berkshire Hathaway Company GTX-326 4–09

The Graver AdvantageGraver Technologies, LLC is a US based companyserving the industrial filtration, separation andpurification needs of companies around the globe.Established over three decades ago, Graver develops,manufactures and markets a wide array of products andservices for the power generation, food and beverage,drinking water, pharmaceutical and chemical markets.Our products are used to efficiently remove particulateand soluble contaminants from a range of gases andfluids. At Graver we strive to understand the needs ofour clients and specialize in providing innovativesolutions for critical processing needs.

Graver Technologies is headquartered in Glasgow,Delaware and has manufacturing and marketingfacilities in Newark, New Jersey, and Honeoye Falls,New York.

Graver Technologies is ISO 9001 Registered andoperates under a strict quality management systemfocused on continuous improvement.

Graver Technologies is a Member of the MarmonGroup of companies, an international corporation withover $7 Billion in annual sales.

©2009 Graver Technologies LLC.

Corporate Headquarters200 Lake DriveGlasgow, Delaware 19702 U.S.A.Telephone: 302-731-1700Fax: 302-369-0938E-Mail: info@gravertech.comWebsite: www.gravertech.com