Filtered by category: Technical Clear Filter

Virtual Fall Conference Includes Session on “Laboratory Testing for Performance Against Bioaerosols”

The American Filtration & Separations Society will devote its entire fall conference on December 2 and 3 to the air filtration industry’s response to COVID-19: What we have witnessed, what we have learned, and what is on the horizon.

To drill down into specific filtration areas that are responding to the pandemic, the conference is offering six sessions:

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Virtual Fall Conference Includes Session on “Face Masks - Industry Updates”

The American Filtration & Separations Society will devote its entire fall conference on December 2 and 3 to the air filtration industry’s response to COVID-19: What we have witnessed, what we have learned, and what is on the horizon.

To drill down into specific filtration areas that are responding to the pandemic, the conference is offering six sessions:

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“Challenges Faced by the Filtration Industry During COVID-19 Pandemic” is Theme for AFS Virtual Fall Conference

The filtration industry has been thrust onto center stage during the COVID-19 pandemic. Never before have we had to confront so immediately and intensely the power of an airborne pathogen to endanger the lives of millions, rock public health and lay waste to the world economy.

The American Filtration & Separations Society will devote its entire fall conference on December 2 and 3 to the filtration industry’s response to COVID-19: What we have witnessed, what we have learned, and what is on the horizon.

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Start with the AFS Buyer’s Guide When Seeking Suppliers

Need a new supplier for a filtration product or service? Let the AFS Buyer's Guide be the first place you look. We have cross-refenced the goods and services of our corporate sponsors into an easy-to-explore catalog.

Our Buyer’s Guide is organized first by primary categories:

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AFS Learning Center Presents Two-Hour Courses on Reverse Osmosis Membrane Technology, Membrane Separation Technologies for Biological and Non-Biological Wastewater Treatment, and Metal Additive Manufacturing (3D Printing) in Filtration

The new AFS Learning Center recently announced four two-hour live virtual courses now available for registration. All courses are $195/members and $295/nonmembers, and all employees of AFS Corporate Sponsors (see list here) can register at the member rate.

The upcoming courses include:

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Fighting Viral Outbreaks with Nanofiber Technologies

Wallace LeungBy Wallace Leung, Chair of World Filtration Congress 13; and past Chair Professor of Innovative Products & Technologies in Mechanical Engineering and past Director, Research Institute of Innovative Products & Technologies at the Hong Kong Polytechnic University, Hung Hom, Hong Kong

The recent outbreak of novel coronavirus, also known as 2019-nCoV, has caused a worldwide concern about a potential pandemic. On January 30, the World Health Organization (WHO) declared the new coronavirus outbreak as a global health emergency. As of the writing of this article, the nCoV has infected more than 20,000 people in 24 countries and killed 426, according to official WHO reports.

The virus can spread from human to human. According to the Chinese Center for Disease Control and Prevention, the size of this virus is about 100nm. When airborne or aerosolized, the virus can be attached to nuclei particles, which can be fine particles in the respiratory tracts or saliva and nasal droplets of an infected person, as well as fine particles suspended in air. Regardless, the minimum size of airborne nCoV is about 100nm when attached to a nano-size particle. The 100nm size airborne particle is referred to as nanoaerosol (also known as nanoparticle or ultrafine particle). While the National Institute for Occupational Safety and Health has standardized N95 and N98 at 300nm, there is no standard filtration test for nanoaerosols at 100nm.

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WFC13 Attracts Professionals on the Global Filtration and Separations Frontier

As the rate of technological advance continues to increase exponentially, there are few disciplines that are expected to keep up with as great an amount and variety of needs. Filtration and separations represent one of those disciplines. Our innovations are critical to countless applications in hundreds of industries, from biopharmaceuticals to emission control, from space travel to freshwater scarcity, and from power generation to virus filtration. There is hardly an area on the frontier of technological change that doesn’t depend on filtration and separations.

The International Delegation on Filtration (INDEFI) was founded by filtration professionals in France, UK and the United States and created the first World Filtration Congress in 1974. Its prime mission is to share information and keep up with the increasing problem-solving demands of filtration and separations technology. INDEFI now includes 13 member countries – Austria, Australia, China, Chinese Taipei, France, Germany, Hungary, India, Japan, Korea, Nordics (Denmark, Finland, Norway, Sweden), UK and the Unites States. Held every four years, this gathering is like no other filtration event due to the extraordinary array of technical and educational offerings and based on the number of countries and industries represented among the thousands of attendees.

Now approaching its 13th Congress (September 20-24, 2021 in San Diego), this exceptional technical forum attracts a wide variety of professionals, including scientists, researchers, academic professors, engineers, practitioners, entrepreneurs, end-users, university students of different disciplines and legislators.

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From Farm to (Operating) Table: Air Quality and Health

Paul MaroldGuest blog by Paul Marold, President of Lydall Performance Materials

Clean air is the most essential resource for life. One could live without food for a few weeks, and without water for a few days; but without air, one would only survive a few minutes, if that.

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Effects of Edge Functional Groups on Desalination Performance in Graphene Oxide Membranes

Only 0.78% of the total water on our blue planet can be used in our daily life. Through water treatment, oceans and other saline water, which account for 97.4% of total global water, have the potential to cover this shortage. Membrane-based technology is the currently favored process for desalination, as it consumes low energy, has low operation cost and has great efficiency.

Commercial membranes are currently made of polymers. These membrane channels are hard to control and therefore have low monovalent ion rejection. Furthermore, some of them have a low tolerance for the chlorine used for sterilization and anti-biofouling. Compared with traditional polymer cross-linked membranes, two-dimensional graphene oxide (GO) based membranes have higher chemical and physical stability. GO nanosheets, which act as an important part, can naturally form a well-packed layer-by-layer membrane structure. This kind of unique membrane structure promotes water permeance via low surface friction while maintaining high salt rejection via edge functional groups of GO nanosheets. Hence, the GO membrane has great potential for industrial water treatment applications. GO nanosheet functionalization can greatly improve membrane performance through channel modification. These characteristics are hard to accurately study via experimental methods because of the nanoscale. Therefore, numerical molecular dynamics (MD) simulations are used to zoom into the nanoscale membranes.

Using MD simulation, surface friction of layer-by-layer membrane with various surface oxidation has been widely investigated. Higher surface oxidation has been proved to improve water slip length inside membrane channels. Furthermore, this higher surface attraction can also increase ion adsorption on the surface of channels that additionally increases the ion rejection rate. The edge functionalization on the layer-by-layer GO-based membrane, whose sieving effect has been proposed from experimental works, is rarely studied. It has been reported that edge functional groups have a significant influence on water permeance. Both interaction and geometric effects of edge functional groups were identified with different GO membrane structures. The study of edge functionalization effects is only limited to water transport performance at present. No work about their desalination performance has been reported, although similar researches have been widely studied on single-layer porous GO membranes. In real experiments, however, it’s very hard to prepare membranes with uniform pore size and keep membranes to a single layer structure in atomic thickness. Layer-by-layer membrane structure assembled by functionalized GO nanosheets is much easier. In addition, filtration efficiency can be largely decreased if the pore size is not well-controlled. Therefore, a study of desalination effects of edge functional groups on layer-by-layer GO membrane is still left untouched but necessary to be processed.

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Face Mask Efficacy in the Age of Coronavirus

Face masks and their availability continues to dominate the news as we cope with the expanding spread of coronavirus in most countries around the world. As filtration leaders, we want to provide a short tutorial on the various kinds of face masks that people are using with the intent to protect themselves and/or others.

A basic rule of air filters is that the more effective they are at removing air contaminants, the more resistant to air flow they are. The air filtration industry has long battled the opposing goals of efficacy and air flow, because as a filter becomes more effective, the greater the energy required to move air through it. In a face mask situation, the more effective (resistant) a filter is, the harder it is to breathe – so you can understand the quandary that we have in developing masks that let in breathing air but not viruses.

The primary danger of wearing a mask that doesn’t do what the wearer thinks it is doing is that it provides a false sense of security, and the wearer might take risks he or she wouldn’t otherwise take, putting themselves or others at risk.

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AFS Presents Three Filtration Fundamentals Webinars in April: Intro to Solid/Liquid Separation I and II, and Meltblown/Nanofiber Technologies

The American Filtration and Separations Society is committed to professional education as one of our primary missions. Even when gathering physically is on hold for the foreseeable future, we are forging ahead with online learning for several of our hallmark courses. For filtration professionals among the millions of people working from home, we present these valuable opportunities to expand your knowledge.

During the week of April 20, AFS will present the following courses:

Tuesday, April 21, 8:00 a.m. – 12:00 p.m. central time: Intro to Solids/Liquids I – Principles
Tuesday, April 21, 1:00 – 5:00 p.m. central time: Meltblown and Nanofiber Technologies
Friday, April 24, 8:00 a.m. – 12:00 p.m. central time: Intro to Solids/Liquids II – Equipment, Operation and Testing

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WFC13 Announces New Dates: September 2021

It is with great pleasure that WFC 13 and AFS leadership announce new dates for the 13th World Filtration Congress: September 20-24, 2021 | Hilton Bayfront, San Diego, CA, USA

We thank everyone for their patience as we worked with the Hilton to identify new dates. In these uncertain times, WFC 13 and AFS leadership agreed to confirm dates later in 2021 to hopefully reduce risk of a repeat pandemic. The Hilton Bayfront has implemented a number of updated processes regarding sanitation. As we negotiated with the hotel, we took into consideration our contracted space in case social distancing is still enforced at the time of the Congress. The safety of all WFC 13 participants is our primary concern.

AFS and WFC 13 staff are working with the confirmed WFC 13 speakers and exhibitors to re-confirm their availability. The content that was to be presented last month will be very similar to what will be presented in September, 2021. Speakers will have the opportunity to update abstracts in 2021 with new information and data. WFC 13’s technical program is unmatched.

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Guest blog by Kathleen Owen, ASHRAE Fellow, ETF member and Air Pollution Control Engineer for Owen Air Filtration Consulting

Have you been asked how MERV filters catch PM2.5?  Obviously, it’s easy to go to the ASHRAE Standard 52.2 MERV table and see that a MERV 13 filter is ≥ 85% in the 1-3 µm particle diameter size range.  This is often the answer you need.  Still the questions keep coming, including from ASHRAE SSPCs 62.1 and 62.2.  With ISO 16890 providing an ePM and these ASHRAE committees deciding to specify filters using particulate matter efficiencies, it became clear that ASHRAE 52.2 needed to address this issue.

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Using a Gas Liquid Porometer to Reliably Measure Pore Size and Distribution for Filter Media Used in Face Masks

Surgical masks and respirators are typically made of nonwoven polypropylene fabric and mostly consist of three (or more) layers. The first and third layers are generally spunbond, while the middle layer is meltblown. This composition is commonly referred to as SMS technology (Spunbond/Meltblown/Spunbond).

Three layers of respirator fabricThree layers of respirator fabric

While the efficiency of face masks is measured by norms defined by ASTM or NIOSH, producers of nonwoven materials need to have insight into the pore size of their material as well.

This document briefly explains how the pore size distribution of these nonwoven materials can be measured using a gas liquid porometer with the ‘pressure scan’ method.

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Next AFS Webinar: Aspects of Designing Media and Filters for Air Filtration

The American Filtration and Separations Society continues to provide world-class filtration educational programming through our new AFS Learning Center. Taught by filtration industry veterans, AFS Short Courses are well known for their high quality and offer .4 CEU credits for each class. AFS members and attendees to any of our 2020 live webinars will receive a discount.

Our next Short Course is Aspects of Designing Media and Filters for Air Filtration, which will be presented on Thursday, July 30, 8:00 a.m. – 12:00 p.m. central time.

This course gives the basis for a better understanding of air filtration theory when applied to filter media and filters, and how other filter requirements, such as environmental regulations, durability and manufacturability have an impact on filter media design. The theoretical principles and practical knowledge gained during this course will allow the participant to be able to properly design and specify filters and filter media for specific applications.

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N95 Mask Material Inventor and AFS Fellow Peter Tsai Exits Retirement to Join Covid-19 Response

Peter Tsai

Long-time AFS member and supporter Peter Tsai has recently received international attention for coming out of retirement to join the battle against Covid-19. As the inventor of the synthetic fabric used to make the N95 mask that is critical in protecting front-line healthcare workers and stemming the spread of coronavirus, Peter started receiving a barrage of requests in mid-March for his knowledge about the nonwoven electrostatically charged material.

With a massive global shortage of the N95 masks, scientists, engineers and clinicians primarily wanted to know: Can the material be sterilized and reused? – and – How can production be scaled up to meet demand? With a willing and curious spirit that has always defined his signature approach, Peter didn’t hesitate to leave the comforts of retirement to help answer these questions. He started working 20 hours a day and even built a lab in his own home to test his ideas.

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Next AFS SW Chapter Meeting: Molecular Separators for Promoting Process Separations in Industrial Applications

The August meeting of the Southwest Chapter of the American Filtration & Separations Society was held Tuesday, August 11, on the topic of Asymmetrical Cake Filtration on Tubular Elements and the Effects on Scalability. Bradley Moakler, North American Regional Manager for DrM Inc., presented.

Proper design of a solid-liquid tubular element filter requires a thorough understanding of all variables within a process. Most small-scale filtration studies are performed with either a downward flow nutsche pressure filter or vacuum filter due to simplicity and overall space and batch requirements. Although this may produce successful results in terms of quality and throughput, several other factors such as cake homogeneity, particle sedimentation, and cake discharge cannot be effectively assessed which can present inaccuracies in sizing and operating a commercial tubular element filter. This presentation examines the inaccuracies that can develop upon scaling to a tubular element filter.

Bradley MoaklerBradley Moakler holds a B.S. in Chemical Engineering from the University of Nevada, Reno. After graduating, he worked as a process engineer for three years in the separations circuit at Molycorp, a rare earth mineral processing mine. He is currently working as North American Regional Manager for DrM Inc., a subsidiary of DrM, Dr. Mueller AG Switzerland, and has been with the company for approximately five years. His work mainly involves sales engineering, process development, and business development.

Join an AFS Committee to Benefit More from Your Membership

When you join AFS, you’ve taken only the first step to realizing value from aligning with the nation’s foremost association for filtration professionals. Members receive discounts on virtual courses and conferences, access to exceptional continuing education and networking opportunities, and free attendance at all AFS chapter meetings. These are all great reasons to join AFS, but people who get the most from their AFS memberships are those who join a committee and start forming long-lasting bonds with other AFS members.

The following active AFS committees and their respective chairs are currently seeking new volunteers:

  • Articles and By-Laws – Chair, Jim Walker
    • Shall ensure that the Articles and By-laws of the Society are consistent with the purpose and needs of the Society.
  • Chapter Affairs – Chair, Wenping Li
    • Shall represent the local chapters at the National Board of Directors meetings and organize, coordinate and implement with the local chapter’s programs to support their activities and growth. The Committee will annually prepare a listing of National Board of Directors members and assign them each to a local chapter closest to their region to reinforce the support of National AFS at a local level.
  • Finance Committee – Chair, Jim Walker
    • Shall recommend financial policies, annually audit the financial transactions, shall arrange for and have conducted an external audit, and shall assist the Treasurer in long-range planning.
  • Marketing and Communications – Chair, Felicia Littlejohn
    • The Marketing and Communications Committee is responsible for content made public by the AFS. In addition, this committee creatively promotes the Society, its conferences and initiatives, promotes AFS to the general public and industry professionals, creates videos, posts to social media, and conducts interviews and surveys to collect feedback from current and potential members.
  • Membership – Chair, John Hancock
    • Shall conduct programs directed toward recruiting new individual members and effectuating membership renewal. The Committee shall also recruit and support active participation by leading companies in the field of filtration and separations.  This committee shall act as the interface between the Corporate Sponsors and the Society.
  • Publications – Chair, Bharath Raghavan
    • Shall maintain and update the master calendar, shall publish a newsletter containing, among other subjects, Chapter and industry information, and shall seek a new journal partnership.
  • Users Committee – Chair, Andrew Goodby
    • Shall encourage the participation of filtration and separations end users in Society functions and advise the AFS Board of Directors in developing programs to increase the activity and membership of vendors and end-users. This Committee shall also conduct and annual New Product/Engineering Merit competition and recognition program for Corporate Sponsors of the Society.  This Committee shall also administer the AFS “Uncle” program for the local chapters to present papers, market AFS and recruit new members for the Chapters and Society.

To volunteer for a committee, please email Lyn Sholl, Executive Director