Thermal power plant presentation

Thermal power plant presentation - Sơ lược về nhà máy nhiệt điện

THERMAL POWER PLANT PRESENTATION

AIM OF THE PRESENTATION

Generally the aim of this presentation is to get the general knowledge/ overview about the thermal power plant to involve with partner to the future project.

Throughout the presentation we’ll discuss about our engineering capacity (manpower/ software/ design tool/ standard…)

POWER PLANTS

A POWER PLANT may be defined as a machine or assembly of equipment that generates and delivers a flow of mechanical energy to electrical energy The main equipment for the generation of electric power is generator When coupling it to a prime mover runs the generator, the electricity is generated

CLASSIFICATION OF POWER PLANTS

THERMAL POWER PLANT

The Steam Power Plant, Diesel Power Plant, Gas Turbine Power Plant and Nuclear

Power Plants are called THERMAL POWER PLANT, because these convert heat

into electric energy.

of generator

THERMAL POWER PLANT IN VIETNAM

THERMAL POWER PLANT

A thermal power plant/ station is a power plant in which the prime mover is steam driven Water is heated, turns into steam and spins a steam turbine which either drives an electrical generator

After it passes through the turbine, the steam is condensed in

a condenser and recycled to where it was heated

The rest of the energy must leave the plant in the form of heat This waste heat can go through a condenser and be disposed of with cooling water or

in cooling towers

THERMAL POWER PLANT OVERVIEW

DIAGRAM OF A TYPICAL COAL-FIRED THERMAL POWER PLANT

COAL CONVEYOR COAL HOPPER

PULVERIZER

BOILER

STEAM TURBINE GENERATOR

COOLING TOWER

CONDENSER

SMOKE STACK

ELECTROSTATIC PRECIPITATOR

THERMAL POWER PLANT

THERMAL POWER PLANT OVERVIEW

COAL FLOW

COAL PULVERIZER/MILL SYSTEM

One of the critical power plant

components that is relied upon to

convert the energy stored in coal into

electricity is the coal pulverizer or

mill

The coal flow is controlled by the

feeder, allowing coal to flow into the

pulverizer mill

 The pulverized coal and air mixture

is then transport to the boiler burner

panels

COAL FLOW

COAL PULVERIZER

The pulverizer receives the raw coal

and reduces it to a very fine,

specified size consist, similar to face

STEAM AND WATER CYCLE

Feed water from the drum the water goes to the down comers and rises in boiler tubes.

This superheated steam which has temperature of (about)540 0 c &

pressure of 139 Kg/cm 2 is used to drive the H.P turbine.

H.P turbine has a temperature of (about)365

0 C and a pressure of 32 Kg/cm 2 enters the re-heater through where its temperature is increased to

540 0 C keeping the pressure constant

The steam goes to the M.P

turbine here some amount of the

steam is extracted and sent to

H.P heaters And the remaining

amount of steam is sent to low

Boiler is a closed vessel in which the heat produced by the combustion of fuel is transferred to water for its conversion into steam

at the desired temperature and pressure

Broadly speaking, a boiler is a device used for generating:

Steam for power generation

Hot water for heating purpose

DESIGN CODE

BOILER & FURNANCE SYSTEM

SUPER HEATER

It is a part of a boiler which consists of number of special steel tubes Depending upon the temperature of steam the diameter of tubes ranges from 25 mm to 64 mm

The wet steam from the boiler is passed through the tubes of super heater where it is dried and super heated by the flue gases on their way to chimney Thus the waste heat energy of flue gases is utilized

ECONOMIZER

Flue gases coming out of the boiler

carry lot of heat Function of

economiser is to recover some of

the heat from the heat carried away

in the flue gases up the chimney

and utilize for heating the feed

water to the boiler It is placed in

the passage of flue gases in

between the exit from the boiler

and the entry to the chimney

STEAM TURBINE

Turbine is the main device to generate electricity It converts steam pressure into mechanical energy and by steam energy, generator produce electricity

In the thermal power plant, three stage steam turbine is used

STEAM TURBINE

WORKING:

►Steam Turbine is used in three stage:

1 High pressure turbine

2 Inter mediate pressure turbine

3 Low pressure turbine

►Some coming from boilers enters HP

turbine first It turned the HP turbine and it

loses its pressure and the temperature and

then steam is taken away from HP turbine

and sent back to the boiler for reheating

This steam enters IP turbine and rotates it

After taken away and directly enters the

LP turbine It rotates the turbine.

► Generator is connected with turbine Generator rotor is also rotates as it connected with turbine Rotor rotates in the stator and cut the flux lines around the coil and thus the electricity generated For cooling of a generator, H2 gas is used

GENERATOR

The main purposes of the condenser are to condense the exhaust steam from the turbine for reuse in the cycle and to maximize turbine efficiency by maintaining proper vacuum As the operating pressure of the condenser is lowered (vacuum is increased), the enthalpy drop of the expanding steam in the turbine will also increase This will increase the amount of available work from the turbine (electrical output)

By lowering the condenser operating pressure, the following will occur:

Increased turbine output

Increased plant efficiency

Reduced steam flow (for a given plant output)

It is therefore very advantageous to operate the condenser at the lowest possible pressure (highest vacuum).

STANDARDS

ASME PTC 12.2 -Steam surface condensers

HEI - Standards for steam surface condensers

TEMA.

FEEDWATER HEATERS

AIR CYCLE

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Primary air fan sucks air from the

atmospherewhich is heated in the air preheater

This air picks coal from the pulveriser and takes to the furnace

Forced draught fan sucks air from the

atmosphere and this is supplied as secondary air

into the furnace for complete combustion

I.D Fan suck flue gas from ESP and discharge into atmosphere through chimeny

COAL BURNER

ROTATING EQUIPMENT SYSTEM

FAN SYSTEM

There are four main types of fans used in thermal power plants:

 Forced draft fans ,

 Induced draft fans,

 Primary air fans,

 Gas-recirculation fans.

PUMP SYSTEM

There are these main service pumps

 Boiler Feed Pump

 Condensate Pump

 Circulating Pump

Remove heat from the water discharged from the condenser

so that the water can be discharged to the river or recirculated and reused

COOLING TOWER

COOLING WATER SYSTEM

 The heat is lost by the water to the

air in the cooling tower by

convection.

 The water coming out of the all the

places go back to the cooling tower

for cooling purpose Some amount

of the water is lost due to

evaporation in the cooling tower

This make up water is taken from

river.

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ASH HANDLING SYSTEM

The water impounded bottom ash hopper receives the bottom ash from furnace where it is stored and periodiocally discharged to the grinder.

The fly ash is collected by the ESP and its below each hopper there is a material handling valve.

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ASH HANDLING SYSTEM

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ELECTROSTATIC PRECIPITATOR

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It is a device which removes dust or other finely divided

particles from flue gases by charging the particles inductively with an electric field, then attracting them to highly charged collector plates.

 A 200 MW capacity power plant using Coals produces as a large as

60000 tons of ash per annum.

 Power plant of 200MW capacity requires 160 hectares area during its

life time it the ashes produced are dumped at the site of the plant.

 The ashes should be discharges and dumped at a sufficient distance

from the power plant because of the following reasons.

(1) The ash is dusty, therefore irritating and annoying to handle.

(2) It is sufficiently hot when it comes out of the boiler furnace

(3) It produces poisonous gases and corrosive acids when mixed with

water.

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ASH HANDLING SYSTEM

SMOKE STACK (CHIMNEY)

A chimney is a system for venting

hot flue gases or smoke from

a boiler, stove, furnace or fireplace to

the outside atmosphere They are

typically almost vertical

SWITCHYARD

BLANCE OF PLANT

 WATER TREATMENT SYSTEM

 WAST WATER TREATMENT SYSTEM

 HYDROGEN GENERATING SYSTEM

 FIRE FIGHTING SYSTEM

 ENVIRONMENTAL SURVEILLANCE

WATER TREATMENT SYSTEM

Steam Boiler system requires a proper Boiler Water Treatment Program with regular water analyses, adequate regulated blowdowns, correct

maintenance, periodic safety checks and periodic inspection follow-up All of these are necessary for long life and efficient boiler service

THANK FOR YOUR ATTENTION