Power Plant Chem
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Transcript of Power Plant Chem
Welcome ToWelcome ToWelcome ToWelcome To
POWER PLANT POWER PLANT FAMILIARIZATION FAMILIARIZATION
CHEMISTRYCHEMISTRYSANDIPT VARSHNEY Sr.MANAGER (CHEM.)
WHY SCARCE RESOURCE IN PLENTY
OF THE TOTAL WATER IN HYDROLOGICAL CYCLE ABOUT 97% IS OCEANIC(BRACKISH)
REMAINING 3%=100 UNITS IS FRESH WATER IN ALL FORMS.
OF THESE 75 UNITS IS LOCKED IN ICE CAPS AND GLACIERS.
14 UNITS IS GROUND WATER BELOW750MTS.
11* UNIT IS GROUND WATER ABOVE 750 MTS
HOW SCARCE IS WATER(*) INCLUDES:-
0.035 UNITS ATMOSPHERIC WATER
0.03 UNITS RIVER WATER
0.06 UNITS SOIL MOISTURE
0.3 UNITS IN LAKES.
NEED TO CONSERVE WATER
THOUGH AVAILABLE IN PLENTY USABLE WATER IS SCARCE
WATER REQUIREMENTS IN POWER PLANTS
CONDENSOR COOLING
AUXILLARY COOLING
FIRE FIGHTING
WATER TREATMENT PLANTCLARIFIED WATERDRINKING WATERDM WATER FOR STEAM GENERATION
SOURCES OF WATER
• SEA WATER• RIVERS• LAKES• CANALS• BORE WELLS• RECYCLED WASTEWATER
TYPES OF IMPURITIES IN RAW WATER
• SUSPENDED IMPURITIES
• DISSOLVED IMPURITIES
• BIOLOGICAL MATTER
• POLLUTANTS (INDUSTRIAL & DOMESTIC)
PTPlant
D M P lant
W TP
S W AS
C W Trea tm entS ys tem
M ain P lant
A m bient A irQ u a lity
M on ito ring
S tack E m iss io ns
E ffluen t T rea tm ent
E n viron m ent m o niter ing
N aph tha& N atu ra l G as
A n a lys is
H yd ro lic & lu beO il A n a lys is
F u e l & O il
Chem istry Section
TREATMENT PROCESS
Pre-treatments of the plant water include:-
• Clarification• Disinfection by chlorine• Removal of organic matter• Filtration• Chemical treatments
PR E T R E AT M E N T PL AN T D E M I N E R AL I Z AT I O N PL AN T
W AT E R T R E AT M E N T PL AN T
WATER TREATMENTS
PRETREATMENT DEMINERALISATION COOLING WATER
TREATMENT STEAM WATER CYCLE
TREATMENT
Salient Features of ANTA
• Units Installed :3 GTs, 3 WHRBs, 1 STG• Capacity
– Gas Turbines :- 3 x 88.71 MW– Steam Turbine :- 1 x153.2 MW
• Source of water :- RMC of Kota barrage on Chambal
River.• CW system Flow :- Approx. 30660 M3/ Hr.
Raw water Characteristic
• pH :- 8.2• TDS:- 170 ppm
• Total Hardness:- 85 ppm as CaCO3
• Ca. Hardness:- 64 ppm as CaCO3
• Magnesium :- 21 ppm as CaCO3
• Alkalinity:- 101 ppm as CaCO3
• Chlorides:- 28 ppm • Organics:- 1.5 to 2.5
Storage Tank
Pressure Filter
Raw Water fromReservoir
Chlorine Lime Alum Clarifier
PROCESS FLOW SHEET OF PRETREATMENT PLANT
To DMplant
Raw
Water
Process flow sheet
PressureFilter
ACF Cation
D / G
WBASBA
MixedBed
Clarifier
DM waterStorage
Tank
D M PLANT
DEMINERALISATION PROCESS
FromACF
Cation MixedBed
Regeneration with caustic
Regenera-tion with HCl
WBA
Analysis
SBA
Analysis
Is quality ok
Analysis Analysis
Regeneration with HCl, NaOH
Is quality ok
Is Quality ok
D/G
DMW storage tank
Is Quality ok
STEAM WATER CYCLE TREATMENT
• LP DOSING (AMMONIA+HYDRAZINE)
• HP DOSING (TSP+ CAUSTIC)
CW pump House
Reservoir Reservoir
Outlet Channel
condenser
Inlet Gate
Outlet Gate
Right Main Canal
InletChannel
CW SYSTEM
WTP
Raw/CW waterP/H
Drinking water
CW make up line
Raw water line
Cooling Towers
SCALING PROBLEM• Steam turbine operation started in August
1990.• 1st Scaling Problem : July 1991, after just
2 – 3 months of closed cycle operations• 1st Chemical cleaning : February . 1992• 2nd Scaling Problem : September 1993
within 2 months of closed cycle operation.• 2nd Chemical cleaning : October 1993
Scales Properties• Thickness : 0.3 to 0.5 mm • Major Constituents :
– Carbonates of Calcium – 42 %– Carbonates of Magnesium – 6%– Quantity of scales removed – 5 to 7 MT
• Chemical cleaning done using inhibited Sulphamic acid.
CW Treatment • In house effort in association with
NTPC R&D.• Started in1994• Chemical Dozed
– pH : 6.8 to7.8– Liquid Chlorine: 0.5 ppm (free chlorine– Zinc Sulphate : 3 to 5 ppm– Sulphuric Acid : to maintain pH– Polyphosphate : 15 to 20 ppm
Parameters maintained
S.No. PARAMETER UNIT REQUIRED RANGE
AVERAGE VALUE
1. pH - 6.5 – 7.5 7.1 ± 0.4
2. Sp. Conductivity us/cm - 800 – 1100
3. Total Hardness mg/l 300 – 500 450 -- 500
4. Chlorides as cl mg/l 150 – 250 100 – 125
5. Silica as Sio2 mg/l 75 18 – 25
6. Inorganic Phosphate mg/l 15 – 20 10 – 15, <5.00**
7. Zinc as Zn Mg/ l 3 – 5 3, < 1.0*
8. COC -- 3 – 5 4.0
**From year 2000 onwards Phosphate &Zinc values restricted to 5 mg/ l and 1mg/ l respectively due pollution norms.
Condenser Performance before and after chemical cleaning
S.No.
PARAMETER
UNIT DESIGN VALUE DATA
PG TEST DATA
AUG.91 (Before descalin
g)
OCT.92(Before descalin
g)
Dec.93 (After
chemical cleaning)
March 04,
1.
CW Inlet C 32.0 32.8 33.0 27.5 23.3 27.9
2.
CW Outlet
C 41.8 43.3 45.0 38.1 33.0 36.9
3.
Δ Temp. C 9.8 10.5 12.0 10.6 9.7 9.0
4.
TTD C 3.8 3.6 15.69 12.7 3.7 3.5
5.
Vacuum Bar
(Abs)
0.102 0.106 0.204 0.155 0.078 0.08
Benefits of the Treatment
• No scaling problem observed in last TEN years.
• No condenser tube leakages occurred in last TEN years.
• Conservation of water by maintaining COC of 5.0.
• Optimum capacity generation by steam turbine, due to improved vacuum.
• Treatment has enabled in indirect saving of Rs 204 lacs/year.
Expected Reduction of Effluents & makeup water for a 1200 MW
station
Make-up Consumptive EffluentsScheme water water water
(cum/Hr) (cum/Hr) (cum/Hr)Conventional scheme 9925 4030 5895
Improved Scheme 6075 4030 2045
Zero Discharge Scheme 4031 4030 practically
zero
WATER REQUIREMENT AT DIFFERENT COC(ANTA)
COC EVAPORATION LOSS
M3/HR
DRIFT LOSS
M3/HR
BLOW DOWN REQD M3/HR
TOTAL MAKE UP
REQD M3/HR
2 600 100 700 1400
3 600 100 350 1050
4 600 100 233 933
5 600 100 165 865
6 600 100 140 840
WATER MANAGEMENT IN ANTA GAS POWER PROJECT
WATER UTILISATION PATTERN
AREA APP. CONSUMP. PER MONTH
PURPOSE
INDUSTRIAL COOLING
WATER450000 M3
Main condenser cooling water & air conditioning system, boiler feed water
DOMESTIC PURPOSE 32000 M3
Potable water to main plant & residential colony
PROCESS CONTROL 7000 M3
PT & DM Plant effluent treatment
Water Effluents Discharges from Anta
• Plant Effluents: 4000 to 5000 M3/ month.• C W Blow down : 45,000 to 50,000M3/
month.• Boiler Blow down:1300 to 1500 M3/ month.• Domestic Sewerage Water : 10,000 - 12,000
M3/ month.• Total Discharges during a month : 62,000 to
70,000M3/ month.
FUEL & OIL
• Analyse Natural Gas For Its Calorific Value On Weekly Basis
• Checking Naphtha Parameters On Requirement
• Analysis Of Lube Oils and Hydraulic oils On Regular Basis to study The Condition Of Oil .
ENVIRONMENT
• Stack Monitoringo Sox & Nox Monitoring
• Ambient Air Quality Monitoringo SPM & RSPM, Sox & Nox Monitoring
Three Locations Inside & 24 Locations Outside The Plant Premises Up to a Distance of 5 Kms.
• Effluent Quality As Per Environmental Normso Main Plant & Sewage Treatment Plant
Effluent Quality Monitoring
(i)PROCESS WATER
StageCapacity
MW
Water Consumption
For Boiler make up
Other ProcessLosses
Total Consumption
in M3
AverageConsumptio
nPer Day
One 419.33 33928 M3 55065 M3 88993 M3 243.8 M3
Water Consumption per unit generation : 1.5 -1.8 Litres/ Kwh
(i)COOLING WATER
StageCapacity
MW
Once through cooling Closed cycle coolingAC & other
coolingHoursWater
consumptionHours
Water consumption
One 419.33 1483 31826070 M3 6210 3740400 M3 25400 M3
Av. Consumption per Day in M3 515054.3 14400.0 69.6
(i)DOMESTIC WATERWater Consumption in 2009- 10, M3
Average ConsumptionIn M3 /Day
336000.0 920.5
RAW MATERIAL CONSUMPTION:
S.NoName of Raw
Material /QuantityName of Product /
Quantity
Consumption of Raw Material Per unit output
During2008-09
During2009 - 10
1Natural Gas/
525482698.0 SMCElectricity /
2898.631 MU0.2265
Smc/Kwh0.2201
Smc/Kwh
2Naphtha /
62897.00 KLElectricity / 103.142 MU
0.2591Litres./Kwh
0.2541Litres./Kwh
3 DM Water / Electricity0.0128
Litres/ Kwh*0.0104
Litres/ Kwh*
4Hydrochloric Acid
(30%)Electricity
0.0090 Gms/Kwh
0.011 Gms/Kwh
5 Caustic Soda Electricity0.0015
Gms/Kwh0.0016
Gms/Kwh
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