Gas Turbine Handbook : Principles and Practices

262 Gas Turbine Handbook: Principles and Practices
PLANT CONFIGURATION
The major components of the facility are the gas turbine generator,
the heat recovery steam generator and the steam turbine generator.
(See Figure 16-1).
The gas turbine generator is a General Electric Frame 7EA model
rated at 89 MW. It is a “Quiet Combustor” unit with 10 combustion
cans and 6 fuel nozzles per can. It utilizes steam injection for NO x
control. The turbine is controlled with a G.E. MK IV microprocessor
based control system.
The waste heat from the gas turbine is absorbed by an unfired
heat recovery steam generator (HRSG) provided by Henry Vogt Machine
Co. It has a generating capacity of 292,860 lbs per hour at a
design pressure of 1570 psi and 101,000 lb/hr of 82 psig steam. It has
a boiler surface of 937,000 sf.
The steam turbine is a dual extraction condensing unit manufactured
by AEG Kanis of Nurnberg, Germany. It is rated at 36 MW.
Process steam to the food facility is supplied by controlled extraction
from the turbine during normal operations. Steam for gas turbine
NO x
control is supplied from a 300 psig uncontrolled bleed line.
During periods of plant shutdown for scheduled non-generating
hours and maintenance, steam is supplied by dual auxiliary boilers.
These are Nebraska Boiler Co. products rated at 86,890 lbs. per hour.
They operate at 170 psi and 378 degrees.
The condenser, supplied by Graham Manufacturing, was designed
to maintain feedwater O 2
less than 5 ppb without the use of
a feed water deaerator. Up to 200 gpm of makeup water is scrubbed
of O 2
by the associated vacuum makeup deaerator. The condenser
handles up to 307,000 lb/hr of exhaust steam using 22,000 gpm cooling
water flow.
A Thermal Energy Storage Inlet Air Cooling System was recently
installed to enhance output of the facility during high electrical
demand periods. It is designed to control gas turbine inlet
air temperature at 43 degrees ±1 degree. The system is comprised
of a 750,000-gallon ice storage tank, refrigeration system utilizing
freon-22 and inlet air cooling coils. The system was designed and
constructed under a turnkey contract by Henry Vogt Machine Co.
During off-peak periods, the turbine inlet air is cooled by an
evaporative cooling fogging system supplied by Mee Industries.