Ikelic - Alliance Digital Repository

COAL
CONSTRUCTION BEGINS ON TECO's POLK
IGCC PLANT
Tampa Electric Company's (TECO) Integrated
Gasification Combined Cycle (IGCC) project in
Polk County, Florida was kicked off with an offi
cial groundbreaking ceremony the first of Novem
ber. The environmental impact assessment for
the project was approved in July, and a final
financing
Department of Energy (DOE)
August.
agreement with the United States
was concluded in
According to TECO's D. Pless, this project was
originally conceived to respond to the Round III
solicitation as part of the Clean Coal Technology
Program. The project was 1 of the 13 selected
from 49 applicants. Notification of award was
received in January 1990. The originally
proposed project was a 120-megawatt air-blown
fixed-bed gasifier supplying a GE 6EA combus
tion turbine/combined cycle powerplant, and in
cluded an in-line zinc ferrite Hot Gas Clean-Up
system. The general objective of this
(HGCU)
project was to demonstrate cost competitive in
tegrated gasification combined cycle with hot
gas clean-up.
Due to difficulties encountered with finalizing the
power sales agreement with the originally in
tended power purchaser, TECO had to search for
other purchasers for the unit's output. It then
became obvious that a more efficient, more reli
able, and more cost-effective arrangement would
be necessary.
To meet these needs, TECO altered the project's
arrangement to include a General Electric 7F(A)
combustion turbine (CT)/combined cycle (CC)
system to significantly increase the power island
efficiency and output. They added a Texaco
oxygen-blown entrained-flow gasifier to increase
the project's reliability due to the Texaco
gasifier's proven track record at Cool Water.
They
also added an air separation unit and
coupled the excess nitrogen to the inlet of the CT
to increase system output, reduce NOx emis
sions and increase overall plant efficiency. In or
4-7
der to enhance the HGCU performance, the sor-
bent will be changed to either zinc titanate or a
patented sorbent from Phillips Petroleum called
Z-Sorb. Finally, to ensure system reliability,
TECO opted to install a conventional 100 percent
cold gas clean-up system in parallel with a
50 percent HGCU system to insure that the IGCC
system would be able to operate regardless of
the status of the HGCU system.
According to TECO's C. Shelnut, the most novel
integration concept in this project is the intended
use of the air separation unit. This system
provides oxygen to the gasifier in the traditional
arrangement, while simultaneously using what is
normally excess or wasted nitrogen to increase
power output and improve cycle efficiency and
also lower NOx formation.
To be more commercially and economically ac
ceptable, a size of 250 megawatts was selected.
The Florida Public Service Commission acknow
ledged that with the DOE partial funding, this unit
would become a least cost power option.
The originally
proposed project called for a
50/50 cost shared arrangement between the par
ticipant and DOE. DOE would provide
$100 million for capital expenses and $20 million
for support during the 2-year demonstration
period. Because the DOE funds were fixed, the
project's support from DOE for the 250-megawatt
unit, on a percentage basis, changed from
50 percent to about 20 percent.
Project Site
The Polk Power site will be built on a Central
Florida inland site in southwestern Polk County,
Florida. The site, about 1 1 miles south of Mul
berry, is a tract previously mined for phosphate
and is basically unreclaimed.
The selected site is about 4,300 acres. About
one-third of it will be used for the generating
facilities. As part of this overall plan, the existing
mine cuts will be modified and used to form an
850 acre cooling reservoir.
THE SYNTHETIC FUELS REPORT, JANUARY 1995