Coal To ElectricityCoal To Electricity

Thermal Power Plant General OverviewThermal Power Plant General Overview

Energy Conversion CycleEnergy Conversion Cycle

Coal

Chemical Energy

Combustion with oxygen

Flue gas containing primarily N2, CO2, CO, excess O2, NOx, SOxThermal Energy

Furnace Zone

Heat transfer

Heat exchangers zone( eco, water wall, S/H etc

Steam

Thermal energy

Shaft work Turbin

eMechanical Energy

Electricity

Electrical Energy

Generator

Thermal expansion

Coal Handling & PreparationCoal Handling & Preparation

Track Hopper

Coal Conveyor Coal

Crusher

Crushed coal Less than 20 mm size

Coal conveyor

Stock yard

Stack reclaimer

Conveyor

Transfer Point

ConveyorCoal tipper

BunkerFeederCoal Mill

FurnaceCoal particle-75 micron

Hot Primary Air

Entropy

Tem

p

1

2

34

Heat rejected

Heat addedHeat rejected

Net Work output

Heat input

Thermodynamic cycle for thermal power plantThermodynamic cycle for thermal power plant

Steam Generator

Turbine

Condenser

BFP

Combustion of coal

Heat transfer

Heat Input

Thermal expansion( work output

Fluid compression(Work input)

Heat Reject

1

2

3

4

Thermal Power plant physical cycle

Carnot CycleCarnot Cycle

Entropy

Tem

p1 1’

2

34 4’

Ti

To

Efficiency = 1-(To / Ti )

Cycle performance improvementCycle performance improvement

Entropy

Tem

p

Ti

To

Ti = Average temp of heat additionTo = Average temp of heat rejection1

2

34

1’

Efficiency = 1-( To / Ti )

TiToEfficiency 1 Ti = Average temp of heat

additionTo = Average temp of heat rejection

Decrease average temp of heat rejection

Increase in efficiency

Increase in average temperature of heat addition

1. Function of ambient temp2. Condenser performance3. Cooling tower performance

1. Increase in operating steam pressure2. Increase in superheated steam temp3. Carrying out reheating at right pressure4. Using regenerative feed heating system

Cycle performance improvementCycle performance improvement

Steam GeneratorSteam Generator

Eco

Furnace

Superheater

HPTReheater

IPT

BLR

HPT IPT LPT GEN

COND

CEP

LPHD/AHPHs

BFP

Block Diagram for power cycle

COAL SIDE OF A POWER PLANTCOAL SIDE OF A POWER PLANT

PROXIMATE ANALYSIS-

Indian American W.Ger.

MOISTURE(%)-

13 16 8.5

ASH(%)- 37.30 15 8.0F.C(%).- 25.70 35.5 60.5

V.M.(%)- 24 33 20.5

GCV (Kcal/Kg)-

3610 5730 6700

SULPHER(%)

0.35 0.5% 1.5%

ULTIMATEULTIMATE ANALYSIS(%):-ANALYSIS(%):-

Carbon-Carbon- 35.635.6

HydrogenHydrogen 2.282.28

SulphurSulphur 0.260.26

NitrogenNitrogen 0.320.32

Oxygen (diff)-Oxygen (diff)- 5.545.54

AshAsh 44.044.0

Hard groove indexHard groove index 5050

Design fuel for NTPC,KORBA received from SECL

Is BITUMINOUS having-

FC-25%,VM-19%,Moisture-12%,Ash-44%,HGI-58

Calorific value (HHV) 3500kcal/kg.

Coal received from SECL- KorbaCoal received from SECL- Korba

Hard Grove Index=13+6.93W

W=Weight of coal passing through 200 mesh after grinding 60 revolutions with 64 lb loading.

What is hard groove index?What is hard groove index?

GRADING OF COAL:-

UHV ( Kcal/ kg ) Grade Above 6200 A5605 – 6200 B4945 – 5605 C4205 – 4940 D3365 - 4200 E2405 - 3360 F1300 - 2400 G

PROPERTIES OF FUELPROPERTIES OF FUEL

FLASH POINTFLASH POINT-IT IS A MINIMUM TEMP AT WHICH THE FUEL -IT IS A MINIMUM TEMP AT WHICH THE FUEL IS HEATED TO GIVE OFF INFLAMABLE VAPOUR IN IS HEATED TO GIVE OFF INFLAMABLE VAPOUR IN SUFFICIENT QUANTITY TO IGNITE WHEN BROUGHT IN SUFFICIENT QUANTITY TO IGNITE WHEN BROUGHT IN CONTACT OF FLAME.CONTACT OF FLAME.

POUR POINTPOUR POINT-IT IS A MIN. TEMP AT WHICH OIL CAN -IT IS A MIN. TEMP AT WHICH OIL CAN HANDLE OR CAN FLOW EASILY IN PIPE LINE.HANDLE OR CAN FLOW EASILY IN PIPE LINE.

FIRE POINTFIRE POINT- IT IS A MIN. TEMP OF FUEL AT WHICH IT - IT IS A MIN. TEMP OF FUEL AT WHICH IT STARTS BURNING WITHOUT EXTERNAL SUPPORT.STARTS BURNING WITHOUT EXTERNAL SUPPORT.

CALORIFIC VALUE-CALORIFIC VALUE- IT IS A HEAT ENERGY LIBERATED BY IT IS A HEAT ENERGY LIBERATED BY COMPLETE COMBUSTION OF UNIT MASS OF FUEL. COMPLETE COMBUSTION OF UNIT MASS OF FUEL.

TRIANGLE OF COMBUSTION

OXY TEMP ABOVE1400F(760 ºC)

FUEL

TIME TEMP

TURBULANCE

FOR EFFECTIVECOMBUSTION

WATER SIDE OF A POWER WATER SIDE OF A POWER PLANTPLANT

WATER SYSTEM

RAW WATER INTAKE PUMP HOUSE & FORE-BAY CHANNEL WITH INFILTRATION CHANNEL

CROSS COUNTRY PIPE LINE 100MM DIA (BURRIED LINE)

RAW WATER RESERVOIR

RAW WATER PUMP HOUSE

CLARIFLOCCULATOR 1&2 FILTER PUMP HOUSE

STILLING CHAMBER & SLUDGE PIT

RCC INLET CHANNEL

CLARIFIED & FIRE STORAGE TANK

CLARIFIED PUMP HOUSE

CHEMICALHOUSE

DM SYSTEM IN OUR PLANT

DM PLANT BUILDING

EXCHANGER AREA (EQUIPMENT

FOUNDATION FOR PSF,ACF,SAC,SBA AND

MB)

REGENERATION AREA

DEGASSER AREA ( TANK FOUNDATION WITH SADLE )

NEUTRALISATION PIT

PUMP FOUNDATION

ACID/ALKALI STORAGE AREA

DM STORAGE TANK

FLOW DIAGRAM OF WATER SYSTEM (RIVER – CWST)FLOW DIAGRAM OF WATER SYSTEM (RIVER – CWST)

DOSING IN PTPDOSING IN PTP

ALUM – To remove suspended solids.ALUM – To remove suspended solids.

LIME - To maintain pH.LIME - To maintain pH.

POLYELECTROLYTE – Used as catalysis and to help in the POLYELECTROLYTE – Used as catalysis and to help in the flocculation process to remove small suspended solids.flocculation process to remove small suspended solids.

CHLORINE – To remove Algae & Microbiological growth.CHLORINE – To remove Algae & Microbiological growth.

PARAMETERS OF TREATED WATER PARAMETERS OF TREATED WATER QUALITYQUALITY

AT THE OUTLET OF PSF - TURBIDITY < 5 NTUAT THE OUTLET OF PSF - TURBIDITY < 5 NTU AT THE OUTLET OF SAC - SODIUM LEAKAGE 2 ppm As CaCoзAT THE OUTLET OF SAC - SODIUM LEAKAGE 2 ppm As CaCoз AT THE OUTLET OF AT THE OUTLET OF

DEGASSER TOWER - Co2 5 ppm As Co2 DEGASSER TOWER - Co2 5 ppm As Co2 AT THE OUTLET OF SBA - SILICA 0.2 ppm As Sio2AT THE OUTLET OF SBA - SILICA 0.2 ppm As Sio2 AT THE OUTLET OF MB - SILICA (DISSOLVED) < 0.02 ppm As AT THE OUTLET OF MB - SILICA (DISSOLVED) < 0.02 ppm As

Sio2Sio2 TOTAL HARDNESS - Not detectable as per ASTM methodsTOTAL HARDNESS - Not detectable as per ASTM methods CONDUCTIVITY @ 25º C - < 0.2 µs / cmCONDUCTIVITY @ 25º C - < 0.2 µs / cm pH - 7.0 ± 0.2 @ 25º CpH - 7.0 ± 0.2 @ 25º C IRON As Fe - Not detectable as per ASTM methodsIRON As Fe - Not detectable as per ASTM methods FREE Co2 ppm - As Co2Not detectable as per ASTM FREE Co2 ppm - As Co2Not detectable as per ASTM

methodsmethods

WORKING MECHANISM OF A WORKING MECHANISM OF A POWER PLANTPOWER PLANT

SCHEMATIC DIAGRAM OF A POWER PLANT

BOTTOM RNG HDR& Z-PANEL 1ST PASS W.W

1ST PASS W.W O/L HDRS ROOF I/L HEADER

2ND PASS UPPER C-HDR 2nd PASS LOWER C-HDRS

LTSH I/L HEADER LTSH O/L HEADER

D.P.I/L HEADER D.P.O/L HEADER

S.H. HEADER R.H.HEADER

2ND PASS ROOF O/L HDR(REAR ECONOMISER

M.S

H.R.HC.R.H

FROM F.R.S

500mw

CONDENSATE & FEED WATER SYSTEM

HOT WELL

CONDENSER

GSC DRAINCOOLER LPH-1 LPH-2 LPH-3

EJECTOR

D/A

D/A FST

HPH-5HPH-6FRS

TO BOILER

LP DOZING

CEP-B

CEP-A

BFP-A,B,C