New process extracts pure hydrogen from contaminant in unrefined
oil
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ARGONNE, Ill. (Aug. 22, 2008) — A commercial-scale process to
extract and reuse pure hydrogen from the hydrogen sulfide that
naturally contaminates unrefined oil, including oil sands, is one
step closer to reality thanks to a collaboration between the U.S.
Department of Energy's Argonne National Laboratory and Kingston
Process Metallurgy Inc. (KPM) of Kingston, Ontario.
Argonne and KPM researchers have invented a molten copper reactor,
an innovative process technology that is more energy-efficient than
existing methods, according to Gregory Krumdick, an engineer in Argonne's Energy
Systems Division. Moreover, the pure hydrogen gas stream
that it extracts can be used to upgrade and clean crude oil and petroleum
products and aid in a number of refining processes, KPM President
Boyd Davis said. Krumdick, Davis, Alain Roy, KPM's vice president
of operations, and former Argonne researcher John Hryn invented the
technology.
In the reactor, hydrogen sulfide gas is first separated
from the crude oil stock, using technology already in place. This
gas is then bubbled though molten copper, which releases pure hydrogen.
The hydrogen is then captured for use as a valued product. As the
sulfur reacts with the copper, the copper is gradually turned into
copper sulfide.
Argonne is collaborating with KPM, a bench-scale process development
firm, under a work-for-others agreement. KPM is supported in part
by Natural
Resources Canada (NRCan), which has provided $600,000
(Canadian) for the research over the last three years.
In addition to generating pure hydrogen, the process creates another
valuable product, concentrated sulfuric acid, which is used widely
in the chemical industry and which has become a valued agricultural
commodity. The concentrated sulfuric acid is created when copper
sulfide is reacted with air to recover the pure copper, releasing
a concentrated stream of sulfur dioxide which is then reacted with
water. The copper is then reused in the process with negligible losses,
Krumdick said.
The reactions between the hydrogen sulfide and copper and the copper
sulfide and air release energy that helps to heat the system, enabling
the researchers to harvest the products efficiently, Krumdick
said. The system operates at a temperature of about 1,200 degrees
Celsius.
"Technologies that are in use today, including the widely used
Claus process, are more energy- and capital-intensive," Krumdick
said. "In addition, they also lose the hydrogen in the process.
Instead of capturing the hydrogen from the hydrogen sulfide, the
Claus process ends up converting it into water."
The multi-step Claus
process was invented more than 100 years ago
and is the most widely used method for removing the hydrogen sulfide
that is present in crude oil and raw natural gas. The Claus process
is also believed to be more limited than the Argonne-KPM process
in terms of the other types of impurities it can handle. Costly energy-intensive
modules that scrub other contaminants, such as ammonia, methane
and carbon dioxide from raw oil and natural gas must be separately
attached to Claus processing facilities.
Argonne computer modeling strongly indicated that the Argonne-KPM
process would deal with those other impurities, a conclusion that
was later experimentally proven. Contaminants such as ammonia and
various hydrocarbons are reformed to their elemental constituents,
providing an added benefit to the process, Krumdick said.
Argonne and KPM continue to scale up their experimental work to
further test the process. "Our goal is to develop a pilot scale
reactor," Krumdick said. "If a pilot plant demonstrates
that the process is a major improvement over existing technology – and
we believe it is – it will spur the interest of industries that use
a process to separate hydrogen sulfide," Davis added.
"Companies will be able to retrofit their facilities with the
process technology or construct new plants that incorporate it," Davis
added. "In the meantime, we are working with Argonne to use
the technology for other energy applications, such as gas cleanup
for Integrated
Gassification Combined Cycle plants."
Argonne and KPM began working on the technology in 2003 as a laboratory-directed
research and development proof-of-concept project.
Kingston Process Metallurgy is an industrial process research and
development company. It focuses on providing quantitative data to
support the development of novel processes and explores business
opportunities in collaboration with customers and partners. It has
clients from around the world who use KPM's expertise in process
development and laboratory experimentation.
Natural Resources Canada (NRCan) works to ensure the responsible
development of Canada's natural resources, including energy, forests,
minerals and metals. It has expertise in earth sciences that it uses
to build and maintain an up-to-date knowledge base of Canada's landmass
and resources. NRCan develops policies and programs that enhance
the contribution of the natural resources sector to the economy and
improve the quality of life of residents, and represents Canada at
the international level to meet the country's global commitments
related to natural resources.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology.
The nation's first national laboratory, Argonne conducts leading-edge basic
and applied scientific research in virtually every scientific discipline. Argonne
researchers work closely with researchers from hundreds of companies, universities,
and federal, state and municipal agencies to help them solve their specific
problems, advance America 's scientific leadership and prepare the nation for
a better future. With employees from more than 60 nations, Argonne is managed
by UChicago
Argonne, LLC for
the U.S.
Department of Energy's Office
of Science.
For more information, please contact Angela Hardin (630/252-5501
or ahardin@anl.gov) at Argonne.
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