a thermal power station

7/28/2019 A Thermal Power Station

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A thermal power station is apower plantin which theprime moverissteamdriven. Water

is heated, turns into steam and spins asteam turbinewhich drives anelectrical generator.

After it passes through the turbine, the steam iscondensedin acondenserand recycled to

where it was heated; this is known as aRankine cycle. The greatest variation in the design of

thermal power stations is due to the differentfossil fuelresources generally used to heat the

water. Some prefer to use the term energy centerbecause such facilities convert forms ofheatenergyinto electrical energy.[1]Certain thermal power plants also are designed to produce

heat energy for industrial purposes ofdistrict heating, ordesalinationof water, in addition to

generating electrical power. Globally, fossil fueled thermal power plants produce a large part

of man-made CO2 emissions to the atmosphere, and efforts to reduce these are many, varied

and widespread.

Contents

[hide]

1 Introductory overview 2 History 3 Efficiency 4 Electricity cost 5 Typical coal thermal power station 6 Boiler and steam cycle

o 6.1 Feed water heating and deaerationo 6.2 Boiler operationo 6.3 Boiler furnace and steam drumo 6.4 Superheatero 6.5 Steam condensingo 6.6 Reheatero 6.7 Air path

7 Steam turbine generator 8 Stack gas path and cleanup

o 8.1 Fly ash collectiono 8.2 Bottom ash collection and disposal

9 Auxiliary systemso 9.1 Boiler make-up water treatment plant and storageo 9.2 Fuel preparation systemo 9.3 Barring gearo 9.4 Oil systemo 9.5 Generator coolingo 9.6 Generator high voltage systemo 9.7 Monitoring and alarm systemo 9.8 Battery supplied emergency lighting and communication

10 Transport of coal fuel to site and to storage 11 See also 12 References 13 External links

Introductory overview [edit]
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ation#Oil_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_coolinghttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_coolinghttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_high_voltage_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_high_voltage_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Monitoring_and_alarm_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Monitoring_and_alarm_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Battery_supplied_emergency_lighting_and_communicationhttp://en.wikipedia.org/wiki/Thermal_power_station#Battery_supplied_emergency_lighting_and_communicationhttp://en.wikipedia.org/wiki/Thermal_power_station#Transport_of_coal_fuel_to_site_and_to_storagehttp://en.wikipedia.org/wiki/Thermal_power_station#Transport_of_coal_fuel_to_site_and_to_storagehttp://en.wikipedia.org/wiki/Thermal_power_station#See_alsohttp://en.wikipedia.org/wiki/Thermal_power_station#See_alsohttp://en.wikipedia.org/wiki/Thermal_power_station#Referenceshttp://en.wikipedia.org/wiki/Thermal_power_station#Referenceshttp://en.wikipedia.org/wiki/Thermal_power_station#External_linkshttp://en.wikipedia.org/wiki/Thermal_power_station#External_linkshttp://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=1http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=1http://en.wikipedia.org/wiki/Thermal_power_station#External_linkshttp://en.wikipedia.org/wiki/Thermal_power_station#Referenceshttp://en.wikipedia.org/wiki/Thermal_power_station#See_alsohttp://en.wikipedia.org/wiki/Thermal_power_station#Transport_of_coal_fuel_to_site_and_to_storagehttp://en.wikipedia.org/wiki/Thermal_power_station#Battery_supplied_emergency_lighting_and_communicationhttp://en.wikipedia.org/wiki/Thermal_power_station#Monitoring_and_alarm_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_high_voltage_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Generator_coolinghttp://en.wikipedia.org/wiki/Thermal_power_station#Oil_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Barring_gearhttp://en.wikipedia.org/wiki/Thermal_power_station#Fuel_preparation_systemhttp://en.wikipedia.org/wiki/Thermal_power_station#Boiler_make-up_water_treatment_plant_and_storagehttp://en.wikipedia.org/wiki/Thermal_power_station#Auxiliary_systemshttp://en.wikipedia.org/wiki/Thermal_power_station#Bottom_ash_collection_and_disposalhttp://en.wikipedia.org/wiki/Thermal_power_station#Fly_ash_collectionhttp://en.wikipedia.org/wiki/Thermal_power_station#Stack_gas_path_and_cleanuphttp://en.wikipedia.org/wiki/Thermal_power_station#Steam_turbine_generatorhttp://en.wikipedia.org/wiki/Thermal_power_station#Air_pathhttp://en.wikipedia.org/wiki/Thermal_power_station#Reheaterhttp://en.wikipedia.org/wiki/Thermal_power_station#Steam_condensinghttp://en.wikipedia.org/wiki/Thermal_power_station#Superheaterhttp://en.wikipedia.org/wiki/Thermal_power_station#Boiler_furnace_and_steam_drumhttp://en.wikipedia.org/wiki/Thermal_power_station#Boiler_operationhttp://en.wikipedia.org/wiki/Thermal_power_station#Feed_water_heating_and_deaerationhttp://en.wikipedia.org/wiki/Thermal_power_station#Boiler_and_steam_cyclehttp://en.wikipedia.org/wiki/Thermal_power_station#Typical_coal_thermal_power_stationhttp://en.wikipedia.org/wiki/Thermal_power_station#Electricity_costhttp://en.wikipedia.org/wiki/Thermal_power_station#Efficiencyhttp://en.wikipedia.org/wiki/Thermal_power_station#Historyhttp://en.wikipedia.org/wiki/Thermal_power_station#Introductory_overviewhttp://en.wikipedia.org/wiki/Thermal_power_stationhttp://en.wikipedia.org/wiki/Desalinationhttp://en.wikipedia.org/wiki/District_heatinghttp://en.wikipedia.org/wiki/Thermal_power_station#cite_note-1http://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Rankine_cyclehttp://en.wikipedia.org/wiki/Surface_condenserhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Electrical_generatorhttp://en.wikipedia.org/wiki/Steam_turbinehttp://en.wikipedia.org/wiki/Steamhttp://en.wiktionary.org/wiki/prime_moverhttp://en.wikipedia.org/wiki/Power_plant


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Almost allcoal,nuclear,geothermal,solar thermal electric, andwaste incineration plants, as

well as many natural gas power plants are thermal.Natural gasis frequentlycombustedingas

turbinesas well asboilers. Thewaste heatfrom a gas turbine can be used to raise steam, in a

combined cycleplant that improves overall efficiency. Power plants burning coal,fuel oil, or

natural gas are often calledfossil-fuel power plants. Somebiomass-fueled thermal power

plants have appeared also. Non-nuclear thermal power plants, particularly fossil-fueledplants, which do not useco-generationare sometimes referred to as conventional power

plants.

Commercialelectric utilitypower stations are usually constructed on a large scale and

designed for continuous operation. Electric power plants typically usethree-phaseelectrical

generatorsto produce alternating current (AC) electric power at afrequencyof 50 Hz or 60

Hz. Large companies or institutions may have their own power plants to supplyheatingor

electricity to their facilities, especially if steam is created anyway for other purposes. Steam-

driven power plants have been used in various large ships, but are now usually used in large

navalships. Shipboard power plants usually directly couple the turbine to the ship's

propellers through gearboxes. Power plants in such ships also provide steam to smallerturbines driving electric generators to supply electricity. Shipboard steam power plants can be

either fossil fuel or nuclear.Nuclear marine propulsionis, with few exceptions, used only innaval vessels. There have been perhaps about a dozenturbo-electricships in which a steam-

driven turbine drives an electric generator which powers anelectric motorforpropulsion.

Combined heat and power plants(CH&P plants), often called co-generation plants, produce

both electric power and heat for process heat or space heating. Steam and hot water lose

energy when piped over substantial distance, so carrying heat energy by steam or hot water is

often only worthwhile within a local area, such as a ship, industrial plant, ordistrict heating

of nearby buildings.

History [edit]

The initially developedreciprocating steam enginehas been used to produce mechanical

power since the 18th Century, with notable improvements being made byJames Watt. When

the first commercially developed central electrical power stations were established in 1882 at

Pearl Street Stationin New York andHolborn Viaduct power stationin London,

reciprocating steam engines were used. The development of thesteam turbinein 1884

provided larger and more efficient machine designs for central generating stations. By 1892

the turbine was considered a better alternative to reciprocating engines;[2]turbines offered

higher speeds, more compact machinery, and stable speed regulation allowing for parallelsynchronous operation of generators on a common bus. After about 1905, turbines entirely

replaced reciprocating engines in large central power stations.

The largest reciprocating engine-generator sets ever built were completed in 1901 for the

Manhattan Elevated Railway. Each of seventeen units weighed about 500 tons and was rated

6000 kilowatts; a contemporary turbine-set of similar rating would have weighed about 20%

as much.[3]

Efficiency [edit]
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.org/wiki/Holborn_Viaduct_power_stationhttp://en.wikipedia.org/wiki/Pearl_Street_Stationhttp://en.wikipedia.org/wiki/James_Watthttp://en.wikipedia.org/wiki/Steam_enginehttp://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=2http://en.wikipedia.org/wiki/District_heatinghttp://en.wikipedia.org/wiki/Combined_heat_and_power_planthttp://en.wikipedia.org/wiki/Marine_propulsionhttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Turbo-electrichttp://en.wikipedia.org/wiki/Nuclear_marine_propulsionhttp://en.wikipedia.org/wiki/Navyhttp://en.wikipedia.org/wiki/Heatinghttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Utility_frequencyhttp://en.wikipedia.org/wiki/Electrical_generatorhttp://en.wikipedia.org/wiki/Electrical_generatorhttp://en.wikipedia.org/wiki/Three-phasehttp://en.wikipedia.org/wiki/Electric_utilityhttp://en.wikipedia.org/wiki/Co-generationhttp://en.wikipedia.org/wiki/Biomasshttp://en.wikipedia.org/wiki/Fossil-fuel_power_planthttp://en.wikipedia.org/wiki/Fuel_oilhttp://en.wikipedia.org/wiki/Combined_cyclehttp://en.wikipedia.org/wiki/Waste_heathttp://en.wikipedia.org/wiki/Boilerhttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Flue-gas_emissions_from_fossil-fuel_combustionhttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Incinerationhttp://en.wikipedia.org/wiki/Solar_thermal_electrichttp://en.wikipedia.org/wiki/Geothermal_powerhttp://en.wikipedia.org/wiki/Nuclear_powerhttp://en.wikipedia.org/wiki/Coal


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ARankine cyclewith a two-stagesteam turbineand a single feed water heater.

The energy efficiency of a conventional thermal power station, considered salable energy

produced as a percent of theheating valueof the fuel consumed, is typically 33% to

48%.[citation needed] As with all heat engines, their efficiency is limited, and governed by the

laws ofthermodynamics. By comparison, mosthydropower stationsin the United States are

about 90 percent efficient in converting the energy of falling water into electricity.[4]

The energy of a thermal not utilized in power production must leave the plant in the form of

heat to the environment. Thiswaste heatcan go through acondenserand be disposed of with

cooling wateror incooling towers. If the waste heat is instead utilized fordistrict heating, it

is calledco-generation. An important class of thermal power station are associated with

desalinationfacilities; these are typically found in desert countries with large supplies ofnatural gasand in these plants, freshwater production and electricity are equally important co-

products.

TheCarnot efficiencydictates that higher efficiencies can be attained by increasing the

temperature of the steam. Sub-critical fossil fuel power plants can achieve 3640%

efficiency.Super criticaldesigns have efficiencies in the low to mid 40% range, with new

"ultra critical" designs using pressures of 4400 psi (30.3 MPa) and multiple stage reheat

reaching about 48% efficiency. Above thecritical pointforwaterof 705 F (374 C) and

3212 psi (22.06 MPa), there is nophase transitionfrom water to steam, but only a gradual

decrease indensity.
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Currentnuclear power plantsmust operate below the temperatures and pressures that coal-

fired plants do, since the pressurized vessel is very large and contains the entire bundle of

nuclear fuel rods. The size of the reactor limits the pressure that can be reached. This, in turn,

limits their thermodynamic efficiency to 3032%. Some advanced reactor designs being

studied, such as theVery high temperature reactor,Advanced gas-cooled reactorandSuper

critical water reactor, would operate at temperatures and pressures similar to current coalplants, producing comparable thermodynamic efficiency.

Electricity cost [edit]

See also:Relative cost of electricity generated by different sources

The direct cost of electric energy produced by a thermal power station is the result of cost offuel, capital cost for the plant, operator labour, maintenance, and such factors as ash handling

and disposal. Indirect, social or environmental costs such as the economic value of

environmental impacts, or environmental and health effects of the complete fuel cycle andplant decommissioning, are not usually assigned to generation costs for thermal stations in

utility practice, but may form part of an environmental impact assessment.

Typical coal thermal power station [edit]

Typical diagram of a coal-fired thermal power station

1.Cooling tower 10. SteamControl valve 19.Superheater

2. Cooling water pump11. High pressuresteam

turbine 20. Forced draught (draft)fan
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3.transmission line(3-phase) 12.Deaerator 21. Reheater

4. Step-uptransformer(3-

phase)13.Feedwater heater 22.Combustionair intake

5.Electrical generator(3-

phase)14.Coalconveyor 23.Economiser

6. Low pressuresteam turbine 15.Coalhopper 24.Air preheater

7.Condensate pump 16.Coal pulverizer 25.Precipitator

8.Surface condenser 17.Boiler steam drum 26. Induced draught (draft)fan

9. Intermediate pressuresteam

turbine18.Bottom ashhopper 27.Flue gas stack

For units over about 200MWcapacity, redundancy of key components is provided by

installing duplicates of the forced and induced draft fans, air preheaters, and fly ash

collectors. On some units of about 60 MW, two boilers per unit may instead be provided.

Boiler and steam cycle [edit]

In fossil-fueled power plants,steam generatorrefers to a furnace that burns the fossil fuel to

boil water to generate steam.

In thenuclear plantfield,steam generatorrefers to a specific type of largeheat exchanger

used in apressurized water reactor(PWR) to thermally connect the primary (reactor plant)

and secondary (steam plant) systems, which generates steam. In a nuclear reactor called a

boiling water reactor(BWR), water is boiled to generate steam directly in the reactor itself

and there are no units called steam generators.

In some industrial settings, there can also be steam-producing heat exchangers called heat

recovery steam generators(HRSG) which utilize heat from some industrial process. The

steam generating boiler has to produce steam at the high purity, pressure and temperature

required for the steam turbine that drives the electrical generator.

Geothermal plantsneed no boiler since they use naturally occurring steam sources. Heat

exchangers may be used where the geothermal steam is very corrosive or contains excessive

suspended solids.

A fossil fuel steam generator includes aneconomizer, asteam drum, and thefurnacewith itssteam generating tubes and superheater coils. Necessarysafety valvesare located at suitable

points to avoid excessive boiler pressure. The air andflue gaspath equipment include: forced

draft (FD)fan,air preheater(AP), boiler furnace, induced draft (ID) fan, fly ash collectors

(electrostatic precipitatororbaghouse) and theflue gas stack.[5][6][7]

Feed water heating and deaeration [edit]

Theboiler feedwaterused in thesteamboiler is a means of transferring heat energy from the

burning fuel to the mechanical energy of the spinningsteam turbine. The total feed water

consists of recirculated condensate water and purified makeup water. Because the metallic

materials it contacts are subject tocorrosionat high temperatures and pressures, the makeupwater is highly purified before use. A system ofwater softenersandion exchange
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demineralizers produces water so pure that it coincidentally becomes an electricalinsulator,

withconductivityin the range of 0.31.0microsiemensper centimeter. The makeup water in

a 500 MWe plant amounts to perhaps 120 US gallons per minute (7.6 L/s) to replace water

drawn off from the boiler drums for water purity management, and to also offset the small

losses from steam leaks in the system.

The feed water cycle begins with condensate water being pumped out of thecondenserafter

traveling through the steam turbines. The condensate flow rate at full load in a 500 MW plant

is about 6,000 US gallons per minute (400 L/s).

Diagram of boiler feed water deaerator (with vertical, domed aeration section and horizontal

water storage section).

The water is pressurized in two stages, and flows through a series of six or seven intermediate

feed water heaters, heated up at each point with steam extracted from an appropriate duct on

the turbines and gaining temperature at each stage. Typically, in the middle of this series of

feedwater heaters, and before the second stage of pressurization, the condensate plus the

makeup water flows through adeaerator[8][9]that removes dissolved air from the water,

further purifying and reducing its corrosiveness. The water may be dosed following this point

withhydrazine, a chemical that removes the remainingoxygenin the water to below 5parts

per billion(ppb).[vague]

It is also dosed withpHcontrol agents such asammoniaormorpholineto keep the residualaciditylow and thus non-corrosive.

Boiler operation [edit]

The boiler is a rectangularfurnaceabout 50 feet (15 m) on a side and 130 feet (40 m) tall. Its

walls are made of a web of high pressure steel tubes about 2.3 inches (58 mm) in diameter.

Pulverized coalis air-blown into the furnace through burners located at the four corners, or

along one wall, or two opposite walls, and it is ignited to rapidly burn, forming a large

fireball at the center. Thethermal radiationof the fireball heats the water that circulates

through the boiler tubes near the boiler perimeter. The water circulation rate in the boiler is

three to four times the throughput. As the water in theboilercirculates it absorbs heat and
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changes into steam. It is separated from the water inside a drum at the top of the furnace. The

saturated steam is introduced intosuperheatpendant tubes that hang in the hottest part of the

combustion gases as they exit the furnace. Here the steam is superheated to 1,000 F (540 C)

to prepare it for the turbine.

Plants designed forlignite(brown coal) are increasingly used in locations as varied asGermany,Victoria, AustraliaandNorth Dakota. Lignite is a much younger form of coal than

black coal. It has a lower energy density than black coal and requires a much larger furnace

for equivalent heat output. Such coals may contain up to 70% water andash, yielding lower

furnace temperatures and requiring larger induced-draft fans. The firing systems also differ

from black coal and typically draw hot gas from the furnace-exit level and mix it with the

incoming coal in fan-type mills that inject the pulverized coal and hot gas mixture into the

boiler.

Plants that use gas turbines to heat the water for conversion into steam use boilers known as

heat recovery steam generators(HRSG). The exhaust heat from the gas turbines is used to

make superheated steam that is then used in a conventional water-steam generation cycle, asdescribed ingas turbine combined-cycle plantssection below.

Boiler furnace and steam drum [edit]

The water enters the boiler through a section in the convection pass called theeconomizer.

From the economizer it passes to thesteam drumand from there it goes through downcomers

to inlet headers at the bottom of the water walls. From these headers the water rises through

the water walls of the furnace where some of it is turned into steam and the mixture of water

and steam then re-enters the steam drum. This process may be driven purely bynatural

circulation(because the water is the downcomers is denser than the water/steam mixture inthe water walls) or assisted by pumps. In the steam drum, the water is returned to the

downcomers and the steam is passed through a series ofsteam separatorsand dryers that

remove water droplets from the steam. The dry steam then flows into the superheater coils.

The boiler furnace auxiliary equipment includescoalfeed nozzles and igniter guns,soot

blowers, water lancing and observation ports (in the furnace walls) for observation of the

furnace interior. Furnaceexplosionsdue to any accumulation of combustible gases after a

trip-out are avoided by flushing out such gases from the combustion zone before igniting the

coal.

The steam drum (as well as the super heater coils and headers) have air vents and drainsneeded for initial start up.

Superheater [edit]

Fossil fuel power plants often have a superheater section in the steam generating furnace. The

steam passes through drying equipment inside the steam drum on to the superheater, a set of

tubes in the furnace. Here the steam picks up more energy from hot flue gases outside the

tubing and its temperature is now superheated above the saturation temperature. The

superheated steam is then piped through the main steam lines to the valves before the high

pressure turbine.
http://en.wikipedia.org/wiki/Superheathttp://en.wikipedia.org/wiki/Superheathttp://en.wikipedia.org/wiki/Superheathttp://en.wikipedia.org/wiki/Lignitehttp://en.wikipedia.org/wiki/Lignitehttp://en.wikipedia.org/wiki/Lignitehttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Victoria,_Australiahttp://en.wikipedia.org/wiki/Victoria,_Australiahttp://en.wikipedia.org/wiki/Victoria,_Australiahttp://en.wikipedia.org/wiki/North_Dakotahttp://en.wikipedia.org/wiki/North_Dakotahttp://en.wikipedia.org/wiki/North_Dakotahttp://en.wikipedia.org/wiki/Coal_ashhttp://en.wikipedia.org/wiki/Coal_ashhttp://en.wikipedia.org/wiki/Coal_ashhttp://en.wikipedia.org/wiki/Heat_recovery_steam_generatorhttp://en.wikipedia.org/wiki/Heat_recovery_steam_generatorhttp://en.wikipedia.org/wiki/Fossil_fuel_power_plant#Gas_turbine_combined-cycle_plantshttp://en.wikipedia.org/wiki/Fossil_fuel_power_plant#Gas_turbine_combined-cycle_plantshttp://en.wikipedia.org/wiki/Fossil_fuel_power_plant#Gas_turbine_combined-cycle_plantshttp://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=9http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=9http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=9http://en.wikipedia.org/wiki/Economizerhttp://en.wikipedia.org/wiki/Economizerhttp://en.wikipedia.org/wiki/Economizerhttp://en.wikipedia.org/wiki/Steam_drumhttp://en.wikipedia.org/wiki/Steam_drumhttp://en.wikipedia.org/wiki/Steam_drumhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Steam_separatorhttp://en.wikipedia.org/wiki/Steam_separatorhttp://en.wikipedia.org/wiki/Steam_separatorhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Explosionhttp://en.wikipedia.org/wiki/Explosionhttp://en.wikipedia.org/wiki/Explosionhttp://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=10http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=10http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=10http://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=10http://en.wikipedia.org/wiki/Explosionhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Soot_blowerhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Steam_separatorhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Natural_circulationhttp://en.wikipedia.org/wiki/Steam_drumhttp://en.wikipedia.org/wiki/Economizerhttp://en.wikipedia.org/w/index.php?title=Thermal_power_station&action=edit&section=9http://en.wikipedia.org/wiki/Fossil_fuel_power_plant#Gas_turbine_combined-cycle_plantshttp://en.wikipedia.org/wiki/Heat_recovery_steam_generatorhttp://en.wikipedia.org/wiki/Coal_ashhttp://en.wikipedia.org/wiki/North_Dakotahttp://en.wikipedia.org/wiki/Victoria,_Australiahttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Lignitehttp://en.wikipedia.org/wiki/Superheat


8/8

Nuclear-powered steam plants do not have such sections but produce steam at essentially

saturated conditions. Experimental nuclear plants were equipped with fossil-fired super

heaters in an attempt to improve overall plant operating cost.

a thermal power station

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