POWER August 2010 - 32

2010 PLANT OF THE YEAR
ure 6). General Electric's Mark VI system
was used to control the steam turbines, also
supplied by GE (Figure 7).
The process of keeping the plant fed with
lignite begins with Luminant's Kosse Mine.
Each of two trains, configured with 36 railcars,
brings a 4,000-ton load of lignite from
the mine a total of seven to eight times a day.
When a train arrives, the bottom dump railcar
can drop its load in a rapid discharge rail unloading
facility in about 55 minutes.
Roberts & Schaefer Co., through a turnkey
contract from Fluor, supplied the coal-handling
system, starting with the rail car unloading
hoppers. Two 1,500 ton/hr (tph) belts transport
crushed coal to a transfer house, where the coal
stream is split to supply the two tripper houses
on each boiler. Each tripper house system has
four reverse shuttle conveyors, each 600 tph,
serving four sets of lignite bunkers with dust
collection at transfer points and lignite silos. The
trippers supply the lignite bunkers on the boiler
structure. The lignite bunkers are sized for about
six to eight hours of operation at full load.
This one-way, dedicated railroad is unremarkable
in the power industry. However, the
plant's " push-pull " connection between the
plant and the lignite deliveries-the mine pushes
the fuel to the plant and the plant pulls its
needs directly from each delivery-is unique.
Either the next train arrives and unloads within
eight hours or the plant runs short of fuel and
must turn to its emergency stockpile. In essence,
the plant's coal pile was moved from the
plant to the mine with deliveries made " just in
time " for the plant's fuel needs.
The typical coal-fired plant is far removed
from its coal suppliers, so it usually keeps 60
days' supply or more on hand, anticipating fuel
delivery disruptions such as those caused by a
failed joint line track from the Powder River
Basin in late 2004. Remarkably small, Oak
Grove's emergency fuel storage stockpile will
keep the plant running for only about 15 days
and is usually tapped only if fuel deliveries are
interrupted. In fact, the fuel pile cannot be accessed
with automated reclaim equipment-
because there isn't any. Oak Grove's fuel pile
was designed without a stacker or reclaimer
system, and recovery of the stored coal is only
possible using a front-end loader to manually
move lignite to the fuel conveyor.
Workflow Management
At the height of the project, Fluor's directhired
construction labor force peaked at
nearly 2,400 workers who contributed about
11 million hours to the project. Fluor support
staff peaked at around 220; of that total,
about 175 were located in Fluor's home office
in Greenville, S.C.
Project leaders also exercised Fluor's global
execution center in New Delhi, India, for about
32
7. Outdoor plant. General Electric supplied the steam turbines used on each unit. Each of
the two units consists of a single-flow high-pressure turbine, double-flow intermediate-pressure
(reheat) turbine, and a four-flow low-pressure condensing turbine with six stages of feedwater
heating. The 345-kV transmission switching station in the background also had been partially
completed when plant construction was suspended in the late 1970s. Courtesy: Luminant,
photo by Allison V. Smith
20% of the engineering work, principally for
the design functions such as piping layout,
electrical connections, and structural design.
Fluor also leveraged its global procurement
network to purchase quality products such as
the chimney, high-alloy pipe, and emissions
control systems at competitive prices and with
shorter delivery schedules. Additionally, Fluor
worked with state and local government representatives
and community and technical colleges
throughout Texas to attract, recruit, and
hire local talent to meet the project's construction
resource requirements.
Workforce Development
Watson joined the project shortly after the final
air emissions permit was received (June
2007) and was promoted to plant director
in late 2009. One of the first tasks the plant
management team had was building the plant
operations team from scratch; only a handful
of the staff transferred from other Luminant
facilities. Over the following months, the staff
slowly began to fuse together as a team-a
challenge to be sure, given that their experience
ranged from first job out of high school
to highly experienced operators. Watson said
that building a plant operations team that was
able to successfully commission Oak Grove
was one of his team's most important accomplishments
on the project.
The Luminant-employed full-time staff
of Oak Grove is currently 148 (excluding
on-site corporate support personnel) plus 38
contractors from Fluor who are responsible
for heavy and mid-level maintenance work at
the plant. The plant staff consists of employee
groups in several different classifications.
" Equipment specialists " and " apprentices "
are responsible for operating equipment and
performing light maintenance duties, such as
www.powermag.com
changing filters, lubrication replacement, and
electrical troubleshooting up to 480V in the main
plant. Equipment specialists are bargaining unit
(BU) employees and members of IBEW Local
2337. " Material specialists " and temporary support
personnel (TSP) employees (also part of the
BU) are responsible for keeping the lignite moving,
starting with when the lignite is dumped
from the bottom of the rail cars and ending
when it enters the silos. Once the lignite enters
the silos, the equipment specialists assume responsibility
for its handling. Material specialists
also perform maintenance functions in their
area of responsibility. Plant operators are also
part of the BU and are stationed in the control
room. Other than a small group of equipment
specialists with electrical knowledge who normally
work a weekday, 8-hour shift, equipment
specialists, apprentices, material specialists,
TSP workers, and others assigned to shift work
use the 12-hour shift schedule over a 28-day
work rotation schedule. The remainder of the
plant staff are non-BU employees and include
technicians (chemical, instrumentation and controls,
environmental, reliability, and planning),
members of the planning and scheduling group,
shift supervisors, contract coordination, site engineering,
and plant management.
The Fluor onsite staff includes journeyman
electricians, boilermakers, certified welders,
millwrights, and other skilled trades. One
very significant advantage enjoyed by Luminant
with its Fluor alliance relationship
comes during major overhauls or during a
major forced outage. Fluor can quickly pull
together just the right combination of journeyman
skills from across the entire Luminant
fleet and from other outside resources
and focus that manpower and expertise on
quickly fixing problems and rapidly returning
a unit to operation.
POWER | August 2010

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POWER August 2010

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