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New Re-gasifying
Process Expected to Save Producer Millions
7/31/2006
By
Angelle Bergeron

When Trunkline LNG Lake Charles, La., terminals
new re-gasifying enhancement goes online in 2008, it is expected
to save the company millions in fuel costs and provide a more environmentally-friendly
alternative to traditional methods. Under a $250-million contract,
Mustang Engineering of Houston will be installing the first Smart
Air Vaporization process in the United States. The LNG Smart Air
Vaporization process captures the natural heat in ambient air and
humidity to vaporize LNG, greatly reducing fuel costs. At
$6 per unit for gas, youre saving $25 million a year in fuel
per Bcf (billion cubic feet), and gas has gone up as high as $14,
says Joe Nelson, midstream engineering manager for Mustang.
Click here to view diagram 177Kb.
By the time Trunkline completes ongoing expansions
in 2008, the terminals average daily sendout will be 1.8 Bcf
per day, with a peak at 2.1 Bcf/d. A Trunkline spokesperson would
not indicate what percentage of sendout will be heated using the
new process, but it is likely to translate into substantial savings
in the cost for fuel that would normally be required to regasify
the LNG. Trunkline filed for Federal Energy Regulatory Commission
certificates and authorizations March 31, and is awaiting approval
to begin construction.
The smart air process involves using air exchangers
to pull in surrounding air, Nelson says. We use a potassium
formate solution as an intermediate fluid that is circulated through
the air heaters. That warms up the fluid, which then goes through
the LNG vaporizer and counter flows. When they are pumped out together,
it is natural gas.
The only emissions from the process are water
and whatever contaminants exist in the ambient air, including dust
particles and bird feathers, Nelson says. We generate 800
gallons per minute per Bcf of fresh water based on 80% humidity,
which is about 900 gallons per minute, he says. Its
really no different than rainfall. If you were able to collect it
and do it in the Middle East, you could probably sell it for more
than oil products.
Comparatively, all re-gas terminals in
the United States are submerged combustion vaporizer (SCV), and the
fuel burned for heating releases emissions of carbon dioxide and carbon
monoxide, Nelson says. The new Trunkline LNG closed system features
a KF/glycol exchanger and LNG Smart supplemental heat system with
shutoff valves make it possible to alternate production between the
two methods, depending upon ambient air temperature. In the
Gulf coast, 89 percent of the time, you would be using just the KF,
Nelson says.
The smart air system provides a welcome alternative
to the open rack vaporizer (ORV) method that is widely used in Japan
but has met with considerable opposition in the U.S. If you
use the ORV, you are taking large amounts of seawater, pumping it
through, adding chemicals to keep corrosion down, and discharging
this water at 8 or 10 degrees cooler than when it comes back in,
Nelson said. That does have a lot of people concerned about
the environmental effects.
Although this is the first time Mustang has
designed a re-gas terminal using the technology, an ambient air
re-gas facility using different fluids and design criteria has been
in service in India for a couple of years, Nelson says. However,
that system uses different fluids and design criteria. Although
it has been successful in reducing emissions, it had to have
a lot more equipment and horse power because it used a glycol, which
gets gummy, Nelson says. Louisiana is the ideal environment
for Mustangs process, which is most efficient at 70 degrees
and 80% humidity, he says. The more humid the climate, the
better the pf solution works. At the Lake Charles, La., facility,
heat backup would still be required during colder months, but between
March and mid-October, a large amount of the heat will likely be
provided by these air vaporizations, Nelson says.
The National Gas Company of Trinidad and Petroleum
Corporation of Jamaica, which is the Jamaican counterpart, partners
in a new LNG facility that is being constructed near Port Esquivel,
about 40 miles west of Kingston, are considering using the process.
It is a perfect place because it never gets below 50 degrees,
and they dont want to burn the fuel because it happens to
be in a shallow bay, Nelson says. We are in the process
of putting the final report out to them in about two weeks. The
actual construction award is not until the second part of 2007.
Mustangs Trunkline contract also
involves installation of a natural gas liquids (NGL) extraction
plant, which will allow the terminal to import supply from more
diverse locations without concern for varying composition of the
LNG. Both pipeline and terminal customers likely will see
benefits of the project for year to come, whether it is in increased
supply, improved gas quality or more competitive usage costs,
says Rob Bond, president and chief operating officer of Panhandle
Energy, Trunklines parent company.
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