TESTIMONY OF
DR. RICHARD BUCHER
W.L. GORE
& ASSOCIATES, INC.
BEFORE THE
SUBCOMMITTEE
ON CLEAN AIR, WETLANDS AND CLIMATE CHANGE
SENATE
COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS
Good
morning, Chairman Voinovich, Ranking Member Carper and members of the
subcommittee. My name is Richard
Bucher, and I am here to speak on behalf of W.L. Gore & Associates, Inc.
about some exciting technical advances that may offer a solution to the vitally
important challenge of reducing mercury emissions.
Gore
is a leading company in the field of advanced materials that provide creative
solutions to long-standing problems. We
believe that a new mercury capture system we have developed, and that has recently
been tested at the EPA, may well offer dramatic improvements in the
effectiveness, efficiency and cost of mercury capture from flue gas. We are very excited by this development, as
an improvement of this kind in mercury control could greatly contribute both to
the long-term sustainability of power generation from coal, and to the health
of all Americans.
I
greatly appreciate the opportunity to testify today. My employer, W.L. Gore
& Associates, is best known as the maker of GORE-TEX® fabrics. Many of you may own or use GORE-TEX®
garments for hiking, hunting or running.
Gore has been using the same high-performance polymer membrane that
makes our fabrics waterproof, windproof and breathable in many other applications
for more than 30 years. We manufacture
a wide range of electronic, medical and industrial materials and devices. Of main interest to us today is the
application of the GORE-TEX® membrane, and related membranes, to the field of
industrial filtration.
Gore
has built a reputation since the 1970s as a leading supplier of
high-performance filter bags to the energy industry, cement kilns, chemical and
metals production facilities, waste incinerators and other industrial
applications. Beginning in the 1990s,
Gore scientists and engineers have discovered and developed a series of radical
improvements to our bags through embedding additional materials and properties
into the structure that makes the bags work.
These advances have led to new applications for capturing over 99.99% of
fine particulate, for catalytically destroying over 99% of dioxins and furans,
and most recently for capturing over 90% of mercury in flue gas streams. The result is a cleaner, safer, healthier
environment and more sustainable industry.
Our
invention in the area of mercury capture has moved well beyond the lab bench
and shows dramatic promise for the future.
Our product relies on the same basic technique as the best current
technology – using activated carbon to capture mercury – but in a way that is
up to two orders or roughly 100 times more effective -- and that has dramatic
positive implications for the waste handling and cost features of our solution.
Current
technologies to control mercury emissions from coal fired power plants include
activated carbon injection, wet scrubber technology, selective catalytic
reduction (SCR) technology, combinations of these, as well as a host of other
potential options. The United States
Environmental Protection Agency’s “Mercury Study Report to Congress” from
December 1997 presents an exhaustive review of the technological options and
their associated financial impact. This
report indicates that active carbon injection represents the greatest potential
for the lowest cost, most technically feasible solution.
Unfortunately,
activated carbon injection has significant drawbacks that make the technology
incompatible with some coal fired power facilities and fiscally prohibitive to
others. A primary drawback of activated carbon injection is contamination of
the facility’s fly ash. Not only does
the presence of the carbon render the fly ash un-salable, but also the presence
of mercury has the potential to require the fly ash to be classified as a
hazardous waste and be disposed of accordingly. Additionally, the literature remains inconclusive regarding the
ability of activated carbon to consistently control elemental mercury
emissions, making this technology potentially incompatible with many existing
facilities burning lignite and Powder River Basin (PRB) coals. Activated carbon injection also requires a
coal fired power plant to purchase, store, inject and dispose of a large volume
of material. This has the secondary
impact of requiring additional footprint and capital expenditures related to
the necessary equipment, and also further burdens the particulate capture
equipment with additional dust loading and pressure drop. Wet scrubber technology is incapable of
controlling elemental mercury emissions, and SCR (selective catalytic reduction)
technology is prohibitively expensive when employed solely for mercury control.
The lack of a financially and technically compelling alternative for mercury emissions control from coal fired power plants led W.L. Gore and Associates, Inc. to create a technology project focused on investigating the feasibility of efficiently trapping and immobilizing gaseous mercury compounds from flue-gas streams using a reactive filter system. The progress to date of this work is summarized in this testimony.
Initial work at Gore focused on developing a wide variety of reactive mercury trapping formulations. A bench-top screening experiment was then conducted to identify formulations with the best opportunity for long-term success. To add credibility and confidence to this study,
all testing was performed at the EPA’s research facility in Research Triangle Park, North Carolina. The mercury test reactor utilized allowed for control of inlet concentrations of mercury, SO2, NOx, H20 and O2. Analysis methods included both continuous mercury monitoring and the widely accepted standard Ontario Hydro test procedure. To accelerate the testing an inlet mercury level of 1 PPM Hg, far in excess of typical coal fired power plant emissions, was selected. To further challenge the samples, testing was conducted at 185°C (365°F), significantly above typical baghouse conditions.

The
key to our technology lies in this increased capacity to capture and hold
mercury. This advance has the potential
to allow the coal fired power industry to move the function of mercury control
from a consumable material, as with traditional activated carbon injection, to
a system component, such as a filter bag or a filter bag insert. Retrofitting a facility with a fabric filter
bag- house already in place can be as easy as dropping mercury trapping inserts
into the existing filters, requiring no additional system infrastructure or
space. Most significantly this approach
does not contaminate the fly ash with mercury-laden activated carbon, allowing
facilities to continue to sell, as opposed to landfill, this valuable
by-product of the coal fired power industry.
Finally, our technology is completely passive in nature. Once installed it is always operating,
continuously protecting the air we breathe, and does not require additional
operators, maintenance or monitoring.
Full size samples have been produced to test mechanical performance and integrity in a full-scale commercial facility. Figure 2 shows a photograph of a full size Gore-TexÒ filter bag with a mercury capture insert. Two such prototypes have been installed on a commercial incineration facility and have been successfully operational since November 2002. This test continues to run to demonstrate long term mechanical integrity.

As
indicated, the development of our technology has progressed from the
laboratory/bench scale phase to pilot testing. Our most significant testing to
date was conducted at the EPA on their pilot scale coal combustion unit. The seven-week trial, with 24-hour operation,
was designed to test the long-term viability of the technology under a variety
of conditions, burning both Powder River Basin (PRB) coal and Lignite coal.
Coal burning trial results, illustrated in Figure 3, indicate mercury capture
rates consistently in excess of 90%.

These
results, assuming further successful field verification, would allow coal
burning facilities to easily comply with the most stringent regulations set
forth in the CLEAR SKIES Act of 2003, and the CLEAN AIR PLANNING Act of 2003,
and would even approach the control levels required in the CLEAN POWER Act of
2003.
As
a private company serving the air pollution control industry for over 30 years,
we at W.L. Gore & Associates clearly realize that even the most advanced
technology must provide our customers an economic advantage. Our mercury technology is being designed to
provide the benefits stated above, while potentially costing considerably less
than activated carbon injection. The
EPA research and development report titled “Performance and Cost of Mercury
Emission Control Technology Applications on Electric Utility Boilers”
identifies carbon injection as the most cost-effective approach available to
date for utilities without existing scrubbers and SCR systems. For example activated carbon injection for a
110 MW facility is projected to cost approximately $700,000 per year. When the lost revenue of un-salable fly ash
is added, these numbers inflate to a range from $1.1MM to $1.5MM per year. Current estimates indicate our technology
could be 38% to 83% lower than these values, making our approach both easier to
implement, and more cost effective.
Although
we have not begun marketing this technology to the coal fired power industry,
our interactions with prospective customers have been nothing short of
extremely encouraging. Owners and
operators of our nations coal fired power plants have expressed enthusiastic
support for our concept, citing the ease of implementation, minimal impact on
system performance, and most of all the preservation of fly ash value which is
so critical to their bottom line.
Indeed initial support has been so strong that most facilities we’ve
interacted with have eagerly volunteered as locations for future
field-testing.
Once
again, I appreciate the opportunity to testify before you today regarding the
important issue of mercury emissions control.
W.L. Gore & Associates remains committed to developing innovative,
economically feasible technologies to address our nation’s air quality
challenges. We look forward to
continuing to work with the Committee, the EPA and the coal fired power industry
to make this technology a commercial reality.
Thank
you again for allowing me to testify, and I’m pleased to answer any questions
you may have for me.

GORE-TEX is a Registered Trademark of W.L. Gore & Associates, Inc.