November/December | Volume 32, No. 6

Growing with the Industry.
The Filtech conference and show goes from strength to strength, with a larger venue planned for the next edition.
By Adrian Wilson, European Correspondent

The busy stand of Hollingsworth & Vose at the show.

Exhibitors at Filtech 2013 were unanimous in endorsing the show as the leading event on the calendar for meeting those vital decision makers within the ever-growing filtration industry. However, in the immediate future, picturesque Wiesbaden will no longer serve as the event’s backdrop – the city’s exhibition center is to be demolished, to make way for a replacement three times its size.

The next Filtech will now be held at the much bigger Messe in Cologne from February 24-26, 2015 — illustrating the event’s growing stature.

Over 200 papers were presented during the conference between October 22-24 of this year, while some 450 exhibitors from 37 countries took part — up 20% from the last event in 2011.

Nanowave expansion
Taking center stage in Hall 1 at Filtech 2013 was Hollingsworth and Vose, one of the key players in nonwoven-based filter media, with manufacturing sites in the Americas, Europe and Asia.

The company announced that it now plans to add NanoWave filtration media production capability at its plant in Hatzfeld, Germany, to support the rapid growth in demand for high performance filter media.

NanoWave is an extended surface area, multi-layer filtration media for HVAC applications. Using nano and coarse fiber layers, it is said to deliver 2.4 times the surface area of normal flat sheet media. The waved nanofiber layer allows for maximum mechanical efficiency with very low resistance, while more than doubling dust-holding capacity compared to standard synthetic media.

The Hatzfeld production line is expected to start operations by mid 2015. H&V currently manufactures NanoWave media in the U.S. at its plant in Floyd, Virginia.

“In addition to the European capacity expansion, further performance improvements and next generation product developments will result in increased service levels for our European customers,” said Jochem Hofstetter, vice-president and managing director, Europe, Middle East and Africa Region (EMEA).

Bindu Muralidharan and Anubhav Verma of India’s a2z demonstrate their technology.

The new Palas MFP Nano Plus

Another leader in filter media is Helsinki-headquartered Ahlstrom, which introduced its new Flow2Save product for high efficiency air (HEA) filtration applications.

The patent-pending media is based on a gradient structure combining different advanced technologies and provides high filtration efficiency to improve indoor air quality, which is especially important in public buildings such as hospitals and schools, and to help alleviate Sick Building Syndrome (SBS).

SBS causes skin irritations, headache, and respiratory problems, and thought to be caused by indoor pollutants, microorganisms or inadequate ventilation.

“Flow2Save has significantly better pressure drop characteristics than other commercial HEA filtration media, meaning it is much easier for the ventilation system to push air through the filter,” explained Fulvio Capussotti, EVP for Ahlstrom Advanced Filtration. “ This allows significant energy savings throughout the life time of the filter. As such, its sustainability credentials are compelling — cleaner indoor air quality, lower energy consumption and lower costs.”

Pigment recovery
Lydall announced that it has teamed up with Limburg Filter, based in Maastricht, Netherlands, to co-develop a best-in-class filtration solution for the recovery of fine pigment powder.

This combines Lydall’s Solupor membrane with Limburg’s Leaktite filtration technology.

Solupor is a porous, durable and chemical resistant, ultra-high molecular polyethylene membrane that produces very high-filtration efficiencies with low-pressure loss. Its current applications include liquid filtration in medical, biopharmaceutical and water purification environments.

Leaktite is a newly developed filtration technology suitable for removal of liquids from slurries using a chamber filter press. It was first proven in the filtration of aqueous graphite dispersions followed by many other applications in the chemical industry.

One of the major filtration issues in the recovery of pigments is that traditional filtration technologies require filtrate recycling — or so-called reflux — until a filter cake has been built up, resulting in a relatively inefficient process. By using the Solupor membrane, the Leaktite filter is now able to provide a single-pass filtration option and increase the efficiency for the recovery of expensive pigments, eliminating the need for reflux.

Porex acquisition
It was also announced during Filtech that the Chicago-headquartered Filtration Group is to acquire Porex Corporation, based in Fairburn, Georgia, from Los Angeles investment firm Aurora Capital.

Founded in 1961, Porex is a global leader in the development and manufacturing of porous polymer products — including plastics, nonwovens and glass-based media. It experienced strong growth during its partnership with Aurora, strengthening its market-leading position through a number of strategic initiatives and streamlining growth through industry-leading innovation.

At Filtech, Porex Vice President and General Manager Jeff Williams demonstrated the Porex 61 tube crossflow filtration module, which consists of 61 half-inch diameter tubes providing some 45.75 square feet of high solids-concentrating surface area per module.

It features unique structural membrane tubes, with the membrane substantially anchored in, or chemically fused to the sintered porous plastic substrate tube.

“The modules are designed for crossflow filtration in the microfiltration and ultrafiltration range,” Mr. Williams explained.

Swiss precision was demonstrated in the form of JCEM’s digital CNC-controlledblade pleating technology.

Vaughan Williams and Debbie Christoff ofDexmet Corporation

“This patented membrane/substrate composite resists damage from scratching and abrasion as well as tolerating high pressure in forward and reverse flow conditions. The resulting composites feature broad chemical, temperature and abrasion resistance.”

Applications include water and wastewater, lime softening, pre-RO, heavy metals removal, fluoride removal and oil water separation.

PEEK strength
Another U.S. company, Dexmet, of Wallingford, Connecticut, promoted the advantages of Victrex PEEK polymer in film form.

“Applications requiring high temperatures to filter caustic gases or fluids, such as in the semiconductor, chemical processing and petrol/gas industries typically employ expanded PTFE, PFA and ECTFE as a support material,” explained Product Manager Debbie Christoff. “All of these materials provide excellent temperature and chemical resistance but none match the mechanical strength provided by PolyGrid Aptiv PEEK films.”

The advantages include dimensional stability on opening size under high flow/high pressure situations, with the increased strength ensuring media integrity and pleat spacing under dynamic flow. The ability to utilize thinner support materials allows the working surface area of the filter to be increased too.

An interesting material with wide potential in filtration is SAF — superabsorbent fiber — promoted by the U.K.’s Technical Absorbents.

SAF is the key component in media designed for the removal of water and particulates from aviation fuel, automotive diesel and a wide range of oils to reduce problems associated with water contamination.

“A significant reason for the majority of oil and fuel system failures is the presence of high water levels in dissolved, dispersed and free water,” said the company’s General Manager Dave Hill. “SAF-based filter media fabrics can remove both dispersed and free water to very low ppm levels at industry leading rates.”

The company has also developed monitor cartridges, which incorporate a multi-layer SAF-containing nonwoven composite.

The cartridges have been designed to reduce particulates to less than 0.3mg/liter of solids in effluent and reduce free and dispersed water to less than 5 ppm in effluent. The system flow is halted when the media is hit with a localized slug of water and a gel block is formed. The presence of water/solids in the incoming fuel gives rise to an increase in pressure differential, or a decrease in the flow rate, as the cartridges reach their maximum capacity for solids, water or a combination of both.

The company supplies cartridges for both automotive diesel and hydraulic oil.

Porex vice-president and general manager
Jeff Williams demonstrates the company’s latest
61 tube crossflow filtration module.

On the testing technology front, Palas introduced the MFP Nano Plus and at the conference, Martin Schmidt explained that because nanoparticles are increasingly becoming the focus of scientific research in respect of the environment and toxicology, the minimization of emissions in the nanometer range and the properties of filter media are gaining in importance.

As a consequence, the recently introduced ISO 29463 standard includes more filter classes compared to the commonly used EN 1822 and the range of a single filter class has been made narrower.

This calls for more sensitive and reproducible test equipment that must also be flexible enough to accommodate DEHS (di-ethyl-hexyl-sebacat ) droplets or salt aerosols in addition to fibers.

The Palas MFP Nano Plus has been developed to quickly and reliably test the MPPS (most penetrating particle size) of flat sheet media. As such, it is equipped with the UGF 2000 aerosol generator to be used for salt dispersion or for the dispersion of DEHS droplets.

Two separate dilution columns for salt or DEHS with dilution factors 10, 100, 1,000 and 10,000 allow a maximum flexibility in the test conditions. The system can also be equipped with various different optical aerosol spectrometers and as such, represents a flexible, reliable and economic filter media testing system.