By: Henry Nowicki, Barbara Sherman and Homer Yute
Like an international cookbook, the attendees of the Ninth Annual International Activated Carbon Conference (IACC) from around the world contributed to a recipe for a successful future for the activated carbon industry. Speakers brought their new ideas and on-going practices together. This annual conference had guests from all over the United States, Canada, Australia, Sri Lanka, Indonesia, Mexico, South Africa and India. The conference connects buyers, sellers and users of activated carbon and related materials and services.
The IACC was held in September. The conference and courses
provide education, which is useful to expand the size and efficiency of the
activated carbon and related sorbent industry.
New Ideas and Products
Mike Havelka from Envirotrol got the conference off to a good start. He
discussed a new granular activated carbon (GAC) treatment to solve the pH rise
problem. It is well-known that when GAC comes into contact with water, a
1–3 pH rise, which can last 50 to 500 bed volumes of GAC, often is
observed. Havelka pointed out that the GAC ash percentage does not change
during this pH rise phenomena and acid washed GAC also exhibits the pH rise
phenomena. Data were presented that the influent water chemistry was
responsible and not the GAC ash. The same lot of GAC was challenged with
different water supplies had markedly different pH rises and duration. (The new
GAC treated product available from Envirotrol is called NoRise.)
Tom Getting from Leopold,
Inc. provided a talk “A Practical
Guide to Sampling and Testing Filter Media” and demonstrated sampling
equipment use. The evening before Getting’s talk, 19 conferees toured a
local municipal drinking water treatment plant to observe backwashing of GAC
filters and sampling demonstrations.
Al Roy and Dan
Leister from MTAZ Global teamed up to present “Common Problems Related
to Activated Carbon Systems.”
They pointed out that the number one problem was failure to wet the
carbon properly. They provided a long list of operating problems they have observed, and solutions were given from their practical experiences.
Professor Jack Pinkerton has provided talks at most IACCs on Internet opportunities. This
year’s presentation was titled “Wireless LANS and Web
Applications.” Wireless connectivity to the Internet is increasing at a
rapid rate. With this increase come benefits and problems. Benefits include
increased access for customers and employees as well as applications such as
instant messaging that permit improved interactive customer relationships.
However, security must be made more complex to prevent loss or theft of
proprietary information and data. Pinkerton has become the resource for
electronic business advice for the IACC members.
Dr. Mick Greenbank
from Calgon Carbon Corp.
provided the one-hour plenary discussion titled “Working Model for
Activated Carbon.” This
practical model is based on a vast accumulation of data. This model changes the
way carbon suppliers and users approach carbon and opens up many new
applications. Also from Calgon Carbon was Leo Zappa. He discussed
“Options in Odor Control New Alternatives and Traditional
Technologies.” He described the market drivers and different solutions to
solve customer odor control problems. Practical solutions to solving these
problems were provided.
Mel Petroccia,
Esquire, from Michael Baker Engineers presented “What Engineering Firms Need from the Carbon
Industry.” Many conference
evaluation comments included the point that they like to hear experts tell them
what carbon users want from the carbon industry. Conference evaluations are
important to provide planning for next year. The 2002 IACC will have speakers
provide these recommendations.
Georgiana Riley, CEO
and president of TIGG Corp.,
gave a presentation on changes and opportunities in the carbon industry. She
pointed out that the price of GAC has fallen 75 percent in the last decade,
which has stimulated a large increase in GAC demand. GAC is now an attractive
impregnant for the catalyst industry. Many more players have arrived in the
industry, requiring increased working together for all to prosper. This large
and diverse group is expected to grow the industry for all.
Homer Yute presented
his latest software program for the activated carbon industry,
“Predictive Adsorption Capacities for Aqueous and Vapor-Phase
Carbons.” The program is based on the Polanyi adsorption model for
heterogenous surfaces and a given correlation curve to determine adsorbates
capacity. This program provides a quick and low-cost activated carbon
feasibility to justify further action.
Dan Burnett
presented a new measurement technology: “Characterization of Acid and
Base Properties of Activated Carbon by Inverse Gas Chromatography (iGC).”
This technique reverses the role of conventional GC—the separation of
components in a complex mixture. The iGC techniques provides information about
the interaction of molecules with different sorbents packed into the GC column.
Dr. Henry Nowicki
presented preliminary work titled “New Modified GAC for Total Arsenic
Control in Drinking Waters.”
The new sorbent removes aqueous Arsenic III and V equally well, and
performance does not depend on the pH. Existing arsenic control technologies
work poorly with As III and better with AsV and have wide differences in
performance depending on pH. This new GAC sorbent offers a low-cost solution to
the global problem of arsenic contamination of drinking water supplies.
Dr. Amos Turk
provided “Activated Carbons for Removal of H2S—Special and Not So
Special.” Turk provided copies of the latest American Society for Testing
Methods (ASTM) method to evaluate hydrogen sulfide (H2S) sorbent capacity. He
pointed out that there are many compounds that make up sewage odor and they
should be considered in later methods designed to evaluate performance.
George Alther from Biomin,
Inc. talked on “Organoclays Extend
Activated Carbon Service Life 7–9 Times in Oily Water.” Alther
pointed out that oil droplets coat GAC and block transport to the interior
microporous structure of GAC, which is important to the GAC adsorption
phenomena. Placing organoclay products in front of GAC solves this oil coating
problem and extends GAC service life seven to nine times.
Hugh McLaughlin,
P.E., discussed “Solvent Regeneration of Spent Carbon.” McLaughlin
applied the new working model for carbon presented by Greenbank. Hugh discussed
some commercial successes with solvent regeneration of spent GAC. Activated
carbon can be regenerated by extraction with organic solvents by a process
using solvents to dissolve adsorbed material out of the internal pores of GAC .
This in-situ process of solvent regeneration is cost effective and can restore
70 to 90 percent of the adsorption capacity of the original GAC without any loss
of GAC.
Wayne Schuliger
talked about coping with bed fires. Through the years there have been bed fires
and temperatures excursions in vapor phase carbon systems. The applications,
which have experienced the most occurrences, are solvent recovery and tank
vents. Proper design and operation procedures were presented to minimize these
incidents.
New test methods and equipment also were presented. Nowicki
discussed a new test method for Methyl-Tertiary Butyl Ether (MTBE) sorbent
performance evaluation. MTBE is a water soluble organic that needs a new test
method to evaluate sorbent performance of its degree of functional active sites
for MTBE. Classical iodine number determinations have been shown to be
inadequate for estimating MTBE sorbent performance.
Henry Perlee
presented “Computerized Instrument for GAC Heat-of-Immersion Measurement
to Estimate Remaining GAC Service Life.” An ASTM draft method for a new
test method based on heat-of-immersion was made available by Turk. Many
conferees provided comments and
suggestions for a new ASTM test method.
References available online at www.waterinfocenter.com.
About The Author: Henry Nowicki, Ph.D., directs the day-to-day laboratory testing and consulting services for PACS Laboratory and Consulting Services. Nowicki has 25 years of practical experiences with activated carbon and other sorbents applied to environmental projects.
