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

drum by the circulating pump. The circulating pump shall take suction from
the drum and shall discharge through the evaporator back to the drum.
Each drum shall be provided with two local level gauges and two level
transmitters. A level transmitter shall send a signal to the level controller
and to a recorder.
3.3.4 Existing Condensate System
The existing condenser is located underside or alongside the turbine, with
an integral hot well located under condenser shell.
Three (3) x 60% capacity condensate pumps take their suction from the hot
well. Condensate also to be used for the following secondary use:
- Spray water for the condensate receiver and flash chamber.
- Vacuum pump seals.
- Turbine exhausts hood spray.
- Chemical injection units.
- Gland seal emergency spray.
- Auxiliary cooling water make-up
- Bypass steam de-superheater spray
- Condenser sparging de-superheater spray.
- Condenser ball cleaning (tube cleaning) system.
Pressure transmitters to be used to provide condensate pump discharge pressure
indication. A pressure switch shall be used to switch to the standby condensate
pump when the operation pump or its motor has failed.
In order to ensure a minimum flow through the gland seal condenser, the condensate
flow to be measured by a flow nozzle and differential pressure transmitter,
which in turn controls the re-circulation flow to the condenser through a
control valve.
The condenser hot well level to be controlled by level transmitters located on
the hot well. The control signals from these controllers shall be programmed so
that condensate shall be dumped to the make-up water tank to prevent high
level in the hot well.
3.3.5 Existing Cooling System
Once through cooling system are used in the existing 210 MW Power plant
The pumps shall be installed in the pit below minimum water level of river.
A circulating water pump house shall be provided.
A manual operated butterfly valve shall be provided at each circulating water
pump discharge and suction.
Motor operated vent valves shall be provided at the top of condenser waterbox
to vent and shut the air automatically.
A motor operated reversing valve shall be provided for condenser backwash
purpose. A chain hoist is provided in circulating water pump house.
Three (3) x 60% intake pumps are installed in the river water pump house
to supply water to the condenser. A portion of which will be used for GT
and GBC cooling system.
Re-Powering Ghorasal 210 MW 3 rd Unit (Vol-2A of 2) 36