2. INTRODUCTION
A Power Plant / Power Station is an industrial facility
for generation of Electric Power.
It is a set-up consisting of systems and sub-systems,
equipments and auxiliaries required for the
generation of Electricity, which involves conversion
of energy forms like chemical energy, heat energy or
gravitational potential energy into Electrical Energy.
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3. ENERGY CONVERSION PROCESS IN
POWER PLANT
The energy content in a primary source of energy, like
Chemical Energy of a Fossil Fuel,
Potential Energy of water stored at a height,
Renewable / Non-conventional sources, like Solar
Thermal Energy, Wind energy, Geothermal Energy,
Tidal Energy,Wave Energy, etc.
is converted stage-wise to Mechanical Energy
(Rotational Energy) to obtain Electricity by creating
relative motion between a magnetic field and a
conductor.
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4. THERMAL POWER PLANTS
In Thermal Power Plants, mechanical power is produced by a
Heat Engine that transforms Thermal Energy, often from
Combustion of a Fuel, into Rotational Energy.
Most Thermal Power Stations produce steam, and these are
sometimes called Steam Power Plants / Stations.
Not all thermal energy can be transformed into mechanical
power, according to the Second Law of Thermodynamics.
Therefore, there is always heat lost to the environment.
If this loss is employed as useful heat, for industrial processes or
distinct heating, the power plant is referred to as a
Cogeneration Power plant or CHP (combined heat-and-power)
plant.
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5. RANKINE
CYCLE
A Thermal Power Plant is a power
plant in which the prime mover is
steam driven.
Water is heated, turns into steam in
Boiler and spins a Steam Turbine
which either drives an Electrical
Generator or does some other work,
like Ship Propulsion.
After it passes through the turbine, the
steam is condensed in a Condenser
and recycled to where it was heated.
This is known as a Rankine cycle – as
shown in the figure.
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A machine that transforms energy from thermal or pressure form
to mechanical form; typically an engine (A mechanical device
used to produce rotation to move vehicle or otherwise provide
the force needed to generate kinetic energy.) or turbine (any of
various rotary machines that use the kinetic energy of a
continuous stream of fluid - a liquid or a gas - to turn a shaft).
A device that converts mechanical
energy to electrical energy, generally
using electromagnetic induction.
6. MORE ABOUT RANKINE CYCLE
The Rankine cycle is a
thermodynamic cycle which
converts heat into work.
The heat is supplied externally to a
closed loop, which usually uses water
as the working fluid.
This cycle generates about 80% of all
electric power used throughout the
world, including virtually all solar
thermal, biomass, coal and nuclear
power plants.
It is named after William John
Macquorn Rankine, a Scottish
polymath.
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G4
7. Slide 6
G4 A polymath (Greek polymathēs, πολυμαθής, "having learned much") is a person whose expertise fills a significant number of subject areas. In
less formal terms, a polymath (or polymathic person) may simply refer to someone who is very knowledgeable.
Guest, 01-01-2002
8. WILLIAM RANKINE
The Rankine Cycle is named after William Rankine. Trained as a
civil engineer, William Rankine was appointed to the chair of
civil engineering and mechanics at Glasgow in 1855. He
developed methods to solve the force distribution in frame
structures.
He worked on heat, and attempted to derive Sadi Carnot's law from
his own hypothesis. His work was extended by Maxwell.
Rankine also wrote on fatigue in the metal of railway axles, on
Earth pressures in soil mechanics and the stability of walls. He
was elected a Fellow of the Royal Society in 1853.
Among his most important works are Manual of Applied
Mechanics (1858), Manual of the Steam Engine and Other
Prime Movers (1859) and On the Thermodynamic Theory of
Waves of Finite Longitudinal Disturbance.
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9. PROCESSES IN RANKINE CYCLE
There are Four processes in the Rankine cycle, each
changing the state of the working fluid.
Process 1-2: Working fluid is PUMPED from low to
high pressure, as the fluid is a liquid at this stage the
pump requires little input energy.
Process 2-3: The high pressure liquid enters a
BOILER where it is heated at constant pressure by
an external heat source to become a dry saturated
vapour (or wet vapour).
Process 3-4: The dry saturated vapour expands
through a TURBINE, generating power. Due to
decrease in temperature and pressure of the
vapour, and some condensation may occur.
Process 4-1: The wet vapour then enters a
CONDENSER where it is condensed at a constant
pressure and temperature to become a saturated
liquid. The pressure and temperature of the
condenser is fixed by the temperature of the
cooling coils as the fluid is undergoing a phase-
change.
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11. RANKINE CYCLE : PRACTICAL CARNOT
CYCLE
The Rankine cycle is sometimes referred to as a
Practical Carnot cycle as, when an efficient turbine is
used, the TS diagram begins to resemble the Carnot
cycle.
The main difference is that a pump is used to
pressurize liquid instead of gas. This requires about
1/100th (1%) as much energy than that in compressing
a gas in a compressor (as in the Carnot cycle).
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16. MAJOR CIRCUITS IN TPP :
Layout of Thermal power plant can be
divided in 4 circuits :
1. Coal and Ash Circuit
2. Air and Gas Circuit
3. Feed Water and Steam Circuit
4. Cooling Water Circuit
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17. POINTS FOR SITE SELECTION OF
TPP
1. Availability of Fuel: 400MW power plant required 5000 to 6000
tons of coal per day
2. Ash Disposal Facilities: ash generated is 20 to 40 % of coal
used. Ash comes out is very hot and very corrosive in nature.
Also it is very hazardous to atmosphere and human health.
3. Nature of Land: Land must have sufficient bearing capacity to
withstand dead load of plant and vibrations of machines.
4. Availability of Water: 60 MW Power Plant required 20 to 30
thousand tons of cooling water and 500 to 600 tons of makeup
water per hr.
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18. 5. Space Requirement: 3-5 acres land required per MW. Mostly
for coal storage and ash handling and another utilities.
6. Transport Facilities: Location should be near to river or sea to
get cheapest transportation of coal by ship or it should be
located near railway track for another cheaper option. Road
transport is costlier then other means.
7. Availability of Labor: Cheap labor should be available.
8. Public Problems: Power Plant should away from town or city
to avoid nuisance from fly ash, coal dust, smoke and heat
discharge from plant.
9. Size of the Plant
POINTS FOR SITE SELECTION OF
TPP (CONTD.)
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