The document summarizes a joint venture between NTPC Ltd and SAIL to form NTPC-SAIL Power Company Private Limited (NSPCL) in 2001. NSPCL took over captive power plants located at Durgapur Steel Plant and Rourkela Steel Plant from SAIL. NSPCL supplies power to Bhilai, Durgapur and Rourkela Steel Plants. It has additionally commissioned expansion projects to meet higher power demands.
2. NTPC Ltd formed a joint venture with SAIL on
50:50 basis in March, 2001 in the name NTPC-SAIL
Power Company Private Limited (NSPCL). NSPCL took
over captive power plant-II located at Durgapur Steel
Plant (2X60 MW) and Rourkela Steel Plant (2X60 MW)
from SAIL.
2
3. To supply power to Bhilai, Durgapur and Rourkela Steel Plants of
Steel Authority of India Ltd. (SAIL) on captive basis from its coal
based captive power plants –II at Bhilai (Chhattisgarh) 2X30 MW +
1X14 MW, Durgapur (West Bengal) 2X60 MW and Rourkela
(Orissa) 2X60 MW. To meet additional captive power requirement
of Bhilai Steel Plant and other units of SAIL, NSPCL commissioned
Bhilai CPP-II Expansion Power Project (2X250MW) during 2008-
09 and commercialized the units during 2009-10. From the
expansion plant, NSPCL is supplying power to the beneficiaries
viz. Union Territory of Dadra & Nagar Haveli , Union Territory of
Daman & Diu, Chhattisgarh and Bhilai Steel Plant / SAIL in the
western region.
3
7. The difference between atmospheric pressure
and the pressure existing in the furnace or flue
gas passage of a boiler is termed as draft.
There are 2 types of draft fans used in thermal
plants:-
1. Induced draft
2. Forced draft
7
8. Placed at the outlet of boiler
Exhausts all gaseous combustion products or
flue gas by creating negative pressure
More susceptible to erosion and corrosion
8
11. Supply the air necessary for combustion
pushing the air through combustion chamber
to the furnace
Most efficient fans in power plants
These are centrifugal fans, uses variable pitch
axial fans
11
12. 12
Definition: An enclosed vessel where heating
of fuel or gas takes place
Place where differential heating takes place
To maximize efficiency water tubes are
constructed
Water tubes absorb the heat
17. Definition: It is a water to steam separator
Water entering into the drum has Temp.
about 3500 C and pressure about170kg/cm2
It is placed 60m high
It includes natural recirculation process
If pressure >190kg/ cm2 ,then forced
recirculation is done
17
19. Ash is the residue remaining after the coal is
incinerated
SiO2, Al2O3, Fe2O3, CaO , MgO are the
components in ash
Ash generated in power plant is about 30-40% of
total coal consumption
2 type of ashes:
1. Fly Ash -Around 80% is the value of fly ash
generated
2. Bottom ash -Bottom ash is 20% of the ash
generated in coal based power stations.
19
20. 20
Bottom Ash Handling System: Bottom ash
resulting from the combustion of coal in the
boiler
Further the slurry is passed through pipes
Coarse Ash (Economizer Ash) handling System:
Ashes generated in economizer
Fly Ash Handling System: Fly ash is considered to
be collected in ESP Hoppers.
22. 22
Turbines form the heart of power plants
Generally to maximize the efficiency, steam
has to be expanded
Work increases in stages
use of HPT,LPT and intermediate turbines
(IPT)- multi stage turbines
HPT and IPT are single flow
turbines(expansion of steam on only 1 side)
having
LPT is double flow turbine with 8 stages.
27. Have fixed nozzle that orients the flow into high
speed jets
High kinetic energy, results in shaft rotation
Drop in the pressure from inlet to outlet
increases the expansion rate of steam
Steam velocity increases
There is a loss of energy due to high exit velocity
which is called as carry over velocity
27
28. A condenser is a device or unit used to
condense a substance from its gaseous to its
liquid state, typically by cooling it.
The latent heat is given up by the substance,
and will transfer to the condenser coolant.
In thermal Power plant we use surface
condenser
28
31. Cooling towers are heat removal devices used to transfer process
waste heat to the atmosphere
Classified into two:
1.HVAC cooling tower
2.Industrial cooling tower
HVAC(heating , ventilation &air-conditioning)- HVAC use of a
cooling tower pairs the cooling tower with a water-cooled chiller
or water-cooled condenser.
Industrial Cooling tower- Industrial cooling towers can be used
to remove heat from various sources such as machinery or
heated process material.
The primary use- cooling towers is to remove the heat absorbed
in the circulating cooling water systems used in power plants.
31
33. An air preheater absorbs waste heat from flue
gas, then transfers this heat to incoming cold
air.
Two types of air preheaters are used: bisector
(one air stream per air heater) and trisector (
two air streams per air heater).
The trisector incorporates both primary and
secondary air within one housing.
33