Tender Document for Repowering Project of Ghorasal 3rd Unit - BPDB

3.0 Power Plant Arrangement
3.1 General
The arrangement of the plant equipment shall be generally as described
below:
Gas Turbine Power Plant (Simple Cycle) with a continuous total net
generating capacity of 65% (+ 5% variation is allowed) of combined cycle
net output shall be accommodated in the location proposed.
The Combined Cycle (GT+ Existing ST) Power Plant with a continuous total
generating capacity at site conditions (35 0 C, 1.013 bar, 98% relative
humidity) of Re-Powered project of Ghorasal 3 rd Unit with inclusion of GTG
and HRSG shall be accommodated in the location proposed with required
number of auxiliary system as per drawing attached. The power plant
general arrangement shall be as per attached drawing.
This specification covers the complete design, engineering, manufacturing,
inspection, testing, supply, delivery to the Site, construction, erection, installation,
testing, commissioning, commercial service and supervision for
the first twenty four (24) months after satisfactory performance tests of a
combined cycle power plant of Re-Powered project of Ghorasal 3 rd Unit
with inclusion of GTG and HRSG at site conditions (35°C, 1.013 bar, 98%
relative humidity) in two (2) identical units of gas turbine generating plant
and one (1) unit of existing steam turbine generating plant suitable at the
Site.
The combined cycle power plant concept shall be based on using the exhaust
heat from the gas turbines for heat recovery steam generator, which
supply steam to the existing steam turbine.
The major equipment of combined cycle plant shall include the two (2) identical
simple cycle Gas turbine generating sets, Two (2) Heat Recovery
Steam Generator, and one (1) Existing 210 MW Steam Turbine Generating
Unit, and a comparable array of auxiliaries. The Existing Steam Turbine
Generating unit shall used to accommodate steam from the heat recovery
steam generator with exhaust heat collected from Gas turbine(s).
The plant arrangement shall be in multi-shaft type i.e. gas turbine drives its
own generator and exhausts into a heat recovery steam generator. The
steam output from the heat recovery steam generator shall be combined in
a header system (for 2:2:1 combination) and directed to a existing steam
turbine. Depending on the station operation mode desired, exhaust gas diverter
dampers shall be able to control flow to either the bypass stack for
simple cycle operation of the gas turbine generating set, or to the heat recovery
steam generator for combined cycle operation, as and when needed
as per system requirement. All of these components shall be selected to
provide low capital and operating costs for mid-range or base-load application.
The unfired heat recovery steam generator shall be pre-assembled in
modules to reduce field erection works. The turbine shall be chosen so that
the maximum plant efficiencies can be obtained.
Re-Powering Ghorasal 210 MW 3 rd Unit (Vol-2A of 2) 32