Mcilvaine Insights


No. 134   February 24, 2020


Weekly selected highlights in flow control, treatment and combustion from the many McIlvaine publications.

·       Impact of the Coronavirus on the Flow and Treat Industry

·       Should we be changing our definitions of air pollutants?

·       FILTXPO Shows How Filter Media Has Important Uses Beyond Particle Capture

·       Holistic Market Approach for FILTXPO Exhibitors


Impact of the Coronavirus on the Flow and Treat Industry

The FILTXP0 will open tomorrow in Chicago with twenty-two empty stands which were slated to be manned by Chinese companies. As of noon on February 24th the Dow Jones Industrial Average had fallen 950 points, or 3.3%, to 28,037, and was down 997 points at its session low. Monday’s decline saw the blue-chip gauge turn negative for 2020, leaving it with a 0.8% year-to-date decline. The S&P 500 slumped 107 points, or 3.2%, to 3,230 and the Nasdaq Composite dropped 368 points, or 3.8%, to 9,209. The S&P 500 and Nasdaq were clinging to year-to-date gains of 0.1% and 0.6%, respectively.

“The number of confirmed coronavirus cases outside of China continued to multiply over the weekend, sending shivers across financial markets as investors were forced to reassess their view that the impact of the outbreak will likely be short-lived,” said Raffi Boyadjian, senior investment analyst at XM, in a note.

Authorities in northern Italy canceled some public events, including Venice’s Carnival, in an effort to reduce the spread of the virus. Italian officials said Sunday they have 152 confirmed cases, the most in any country outside Asia. European stock markets fell sharply at the open, with the FTSE MIB Italy index  slumping over 5%.

Asian equity markets also sold off after the number of cases in South Korea shot up over the weekend. South Korea reported 70 more cases and a lawmaker in Iran said the death toll from the city of Qom is 50.

As the coronavirus continues to spread, so does the fear of many Americans. Pharmacies and online retailers worldwide, have begun running out of face masks.  Walgreen's and CVS stores across Knoxville have reported a shortage of face masks and gloves because of recent high demand.

In a new survey, the National Community Pharmacists Association said nearly 63 percent of U.S. pharmacists said they've had customers buy surgical masks as a precaution against coronavirus. Nearly 96 percent of U.S. pharmacists said the demand has led to shortages as retailers wait to restock shelves.

The battle to contain the Chinese coronavirus threatens to cut U.S. companies off from parts and materials they need to produce valves and pumps which rely on castings and forgings made in China. Some of the United States’ best-known manufacturers such as General Electric, Caterpillar and the Big Three automakers, along with many smaller American businesses, depend on what is made in Chinese factories.


Should we be changing our definitions of air pollutants?

The definitions of air pollutant quantities are based on tradition and are often not the most accurate selections. Sensor based ambient air monitors are less costly than analysers or permanent samplers but there has been questions about their accuracy. Dubai solved this problem with a mobile EPA qualified analyzer system and fourteen Aeroqual sensor based systems.  China has installed 10,000 Sailhero sensor based systems that correlate closely with analyzers for each of the major pollutants. The regulations relative to toxic metals require polluters only to limit PM 2.5 which is used as surrogate for toxic metals. This is despite the fact that some metals are 100,000 x more toxic than others.  This is despite the fact that the employment of multi metals analyzers in a St. Louis ambient monitoring program showed that levels of certain highly toxic metals varied depending on the wind direction.

Opacity is still used for regulatory purposes. Its origin was long before scrubbers were employed after the particulate collector.  In most cases scrubbers provide additional particulate removal but, in some cases, when they malfunction, they increase particulate discharges. But believe it or not opacity regulations require measurement prior to the scrubber since opacity cannot be measured in a wet stack.

Power plants and other combustion sources are required to limit their emissions of gas phase mercury. This is based on the fact that prior to attempted control mercury is in the gas phase.  However, when activated carbon is injected, the mercury becomes attached to particles. If these particles are not captured, they can fall in the vicinity of the plant.  In contrast gas phase mercury may travel across continents.  It is therefore possible that mercury control could result in greater mercury contamination near the source than if there were no controls.  Permanent samplers will capture particulate mercury but can be modified to segment the particulate and gas phase.  The Cooper mercury analyzer also measures total mercury.  Doesn’t it make sense to regulate total mercury?

The fundamental principles are also murky. Particulate is defined as the diameter of a sphere and the particle weight is assumed. In fact, particles are not spheres and their specific gravity varies. The cascade impactor is used to determine particle size. But it creates its own definition which does not magically transform hair shaped particles into spheres of equal gravity.

The McIlvaine Company identified this problem relative to the sizing of wet high energy particulate scrubbers based on particle size. Purchasers who relied on particle size analyses in many cases experienced disastrous results. McIlvaine addressed this problem with the invention of the McIlvaine mini scrubber. It is a 1 cfm device where the energy in the turbulent zone can be varied and the results determined in mg/m3.

The impact of ambient particulate could be addressed in a similar manner. A miniature lung equivalent could be used to determine how much penetrates and how much is captured on the surface. It is likely that cascade impactor measured particles of 2.5 micron diameter penetrate differently. So, the new definition would be particles which penetrate the lungs vs those which do not.

EPA standards for ambient measurement of pollutants have been adopted around the world. But when China and Dubai use methods which may be equally indicative even if they don’t correlate 100% with EPA methods, there is eventually going to be a movement toward a new standard.

Toxic metals need to also be addressed. The concern is not only the particle penetration aspect but the toxicity. There are now multi metals analyzers which can measure the concentration of 17 different metals.  So the lung penetration index could also be adjusted based on a toxic metal harm quotient. In St. Louis when winds blow from the south, consistent with the bearing of the Doe Run Herculaneum lead smelter the toxic metal harm index is likely to be much higher than would be reflected by PM 2.5 measurement. McIlvaine has long promoted the use of a toxic metal harm metric which would take into account the relative contribution of each metal.  This would be of more benefit to St Louis citizens.  This common metric can be expanded to all pollutants and be a much better guide as to whether to remain indoors. This is explained at Sustainability Universal Rating System    

More details on air monitoring technology and markets are contained in Air Pollution Monitoring and Sampling: World Markets  For more information on this program contact “Bob McIlvaine at  or 847 784 0013.

FILTXPO Shows How Filter Media Has Important Uses Beyond Particle Capture

FILTXPO will be held in Chicago February 25-28. It is going to be an entirely different experience than the previous conferences.  INDA has taken the position that it can help its non-woven media members best by providing knowledge about the solutions and help them become proactive in developing new solutions. INDA has acquired Filtration News who provides insights on solutions. It has expanded the exposition to cover solutions in a number of areas. McIlvaine Company is writing monthly “true cost” feature articles for Filtration News which assess lowest total cost of ownership based on the filter impact on the total solution.

The total solution can be more than just particle capture. Filter media is utilized for absorption, adsorption, catalysis, and even killing of viruses. 

Coronavirus: The use of ultraviolet light to kill viruses is a function of contact time. A HEPA filter can provide the residence time. Ultraviolet light applied to the filter media then kills the viruses. Attendees will be keenly aware of the virus challenges since none of the Chinese exhibitors will be in attendance due to the coronavirus.  Many of the INDA members are challenged by large demand for face masks. There will be accelerated development of N 95 masks using copper oxide or other biocidal agents as well as design developments for reducing cost, increasing efficiency, and making them more user friendly.

There will be the need to adopt cleanroom technology in an emergency. If the cruise ship which allowed 300 people to become positive for coronavirus had been operated as a pharmaceutical cleanroom, the number of infections could have been reduced.

Catalysis: Filter media is being impregnated with metal particles which have a catalytic effect in converting VOCs and NOx.  Instead of two big vessels in an air pollution control system it can be reduced to just one.

Adsorption:  Combining filtration and adsorption has become routine with activated carbon layers in filter media. This capability is being exploited for household odors and water purification. By injecting activated carbon ahead of a fabric filter in an air pollution control system mercury and VOCs can be captured.

Absorption: The catalytic filter can be preceded by injection of sodium or calcium compounds in the gas stream. This means one vessel is used instead of three to remove acid gases, NOx, and particulate. By using ceramic filtration elements gas can be cleaned at 850F and the heat recaptured. This has a net effect of reducing CO2 and reducing operational cost.

The biggest near-term opportunity for filter media companies involves the so-called dry scrubber.  Spray driers using lime slurry or circulating loops using powdered lime are situated ahead of a fabric filter. The filter cake acts to complete the absorption. Even though a large percentage of fabric filters are now expected to remove both acid gases and particulate, they are still designed for what can be described as LIFO vs FIFO operation. They need to be redesigned so that the first lime forming the cake reacts and is pulsed away making room for fresh lime.

Biopharmaceuticals offer a big opportunity for filter media companies to innovate. FILTXPO has several sessions on this subject.  This includes a paper on membrane chromatography using non-woven media with lots of potential advantages as explained in the abstract below.

High Productivity Nonwoven Membrane Adsorbers For Biological Product Capture

Ruben Carbonell, Ph.D.

Chief Technology Officer - NIIMBL and Professor of Chemical and Biomolecular Engineering, North Carolina State University

Packed bed chromatography is by far the most common technique used for high resolution separations of proteins. Membrane chromatography is a relatively new technique developed for the purpose of operating at higher flow rates and at reduced process times relative to resin-based column chromatography. Higher flow rates are possible with membranes because the resulting pressure drops are significantly lower than in resin columns, and dynamic binding capacities do not decrease significantly with shorter residence times because of the lack of diffusional resistance to product capture on the membrane surface. In addition, membrane adsorbers are generally single-use devices that eliminate the difficulties and costs often associated with packing a chromatographic column, and the cleaning and validation steps required of multi-use columns.

One significant drawback associated with the use of membrane adsorbers in a capture mode is that their dynamic binding capacities are generally lower than those of column chromatography resins. As a result, the industrial application of membrane adsorbers has been largely limited to flow-through polishing applications in which low concentration impurities bind to the membrane media, while product flows through. Indeed, with the development of novel membrane materials with higher binding capacities the use of membrane adsorbers for product capture is of increasing interest.

To this end, our laboratory has developed strong and weak anion and cation exchange membranes based on poly(butylene) terephthalate (PBT) nonwoven fabrics grafted with glycidyl methacrylate (GMA). The presence of the glycidyl methacrylate layer allows functionalization with cation and anion exchange groups that have dynamic binding capacities (DBCs) at very short residence times (0.1 – 0.5 minutes) that are similar to the DBCs obtained in some of the best available ion exchange chromatography resins at longer residence times. Consequently, these nonwoven membranes have a considerably larger productivity than their resin counterparts. The relatively inexpensive nonwoven membrane materials enable single-use disposable operation, and the membranes can produce high yields (>97%) and purities (>96%) of IgG from CHO cell culture. The availability of such devices could have a significant impact on current bioprocess operations by providing an alternative single-use disposable product capture step with a significantly higher productivity than resin packed column chromatography.

Bob McIlvaine will be gathering news for future IFN true cost articles at the exposition.  If you would like to talk to him, he can be reached by cell phone at 847 226 2391 or


Holistic Market Approach for FILTXPO Exhibitors



Click here to schedule a booth visit


True costs and the SAM are available for each liquid and air filtration product. SOM programs for each are being pursued.  Here is a partial list of applications of media and the product options.



Element 1

Element 2

Element 3

Element 4

Element 5

Air Filtration


Cabin Air


pre filter




Engine Intake

Gas turbine 

pre filter

static filter





carbon layer



Compressed Air

        Dust Collector




Liquid Filtration


Fuel Water




cross flow







cross flow






non -wovens




Market forecasts (SAM) are available for each of the above products in each industry in each country of the world. Here are forecasts from two McIlvaine reports.


Air Filter Sales $ millions










 G 1-4



 Gas Phase



 H 10-17



 M 5-6, F 7-9





Liquid Cartridge Sales  $ millions




 - Total















 String Wound




The True cost articles appearing in IFN are part of an extensive effort to analyze technology and then predict market shares and market growth.  Here is a news release for FILTXPO on combining particle filtration with absorption, adsorption, catalysis, and destruction.


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