Post on 18-Jan-2016
description
DETAILS OF CALCULATIONS:
POWER OUTPUT = 660 MWTOTAL ENERGY DELIVERED @ 660 MW FOR A PERIOD OF ONE HOUR =
660MWHTaking Efficiency = 37.96 % and 90 % PLF
Input = 660* 103 x 0.9 x 860 kcal / 0.3796 = 1345732.35 Kcal (1 KWH = 860kcal)
Design calorific value of coal = 3300 Kcal/ kg
Coal requirement per hour = 1345732.35 / 3300 = 408 T
At efficiency 38.96 % coal requirement per hour = 397 T
Yearly saving of coal by increasing efficiency of 1 % = 11 x 24 x 365 days = 96,360 MT
Total value of the coal saved @ Rs 650 / MT = Rs 626 lakhsIf the efficiency increases by 2.5 % = Rs 626 x 2.5 = 1565 Lakhs
Considering the life time as 30 Years, the savings in Fuel cost will be Rs 46950 Lakhs ~ 470 Crores
For three units = 470 x 3 = 1410 Crores
INDIRECT SAVINGS
Assuming Auxiliary Power consumption as 8 %
Estimated reduction in auxiliary power consumption = 0.3 %
For 660 MW units savings of auxiliary power= 8 % x 660 x 0.003 = 0.158MW
Yearly savings in MW = 0.158 x 365 x 24 x 0.9 = 1248 .825 = 1248825 units
Taking the unit cost as Rs 2.50 per unit Savings = 32.00 Lakhs
Total for three units = 32 x 3 = 96.00 Lakhs ~ 1.0 Crores
For life time = 30. CroresTOTAL = 1410 + 30 = 1440 CRORES
ASSUMING THE LIFE AS 30 YEARS, THE APPROXIMATE SAVINGS WILL BE RS 48 CRORES PER YEAR FOR ALL THREE UNITS TOGETHER.
INCREASE IN PLANT EFFICIENCY by SUPER CRITICAL PARAMETERS
1.5
0.90.6
3.2
167 bar538/538’c
250 bar538/538
250 bar540/560’c
250 bar580/600’c
250bar566/566 ‘c
1
2
3
4
5
6
.
Efficiency Increase
Comparison of BHEL V/s Doosan UnitsComparison of BHEL V/s Doosan Units
Doosan UnitsDoosan Units• Total Weight- 27960
MT– Structure – 6924 MT– Pr. Parts – 7080 MT– P C Piping – 3032 MT– P F System – 3823 MT– Draft System – 5004
MT– Refractory/Insulation
C&I/Misc – 2097 MT
BHEL UnitsBHEL Units• Total Weight- 28585
MT– Structure – 10801 MT– Pr. Parts – 5800 MT– P C Piping – 1445 MT– P F System – 2342 MT– Draft System – 5680 MT– Refractory/Insulation
C&I/Misc – 2517 MT
Description unit 660 500
S/H STEAM FLOW T/HR 2225 1625
SH STEAM PR KG/CM2 256 179
SH STEAM TEMP 0C 540 540
RH STEAM FLOW T/HR 1742 1397.4
RH STEAM TEMP INLET 0C 303.7 338.5
RH STEAM TEMP OUTLET 0C 568 540
RH STEAM PRESS INLET KG/CM2 51.17 46.1
FEED WATER TEMP 0C 291.4 255.2
COMPARISION OF 660 MW Vs 500 MW BOILER
Description 660 MW 500 MW
Structural Steel Erection 7383 9200
Boiler Proper & Accessories (Pre. Parts) 7080 5300
Refractory, Insulation & Cladding 1410 2000
Power Cycle Piping 3032 2200
Soot Blowing System 54 76
Coal Firing System 3573 2000
Draft System 5275 5200
Fuel oil system 62 200
Miscellaneous System 130 280
Electrical & Instrumentation 282 380
TOTAL 28281 26836
Tonnage Comparison
Material Comparison
Description 660 MW 500 MW
Structural Steel Alloy Steel Carbon Steel
Water wall T22 Carbon Steel
SH Coil T23, T91 T11, T22
RH Coil T91,Super 304 H T22, T91,T11
LTSH T12 T11
Economizer SA106-C Carbon Steel
Welding Joints (Pressure Parts) 42,000 Nos 24,000 Nos
Structural Comparison
Slno 660 MW 500 MW Remarks
1 STRUCTURALS
a
Entire structural is bolting type- entire structure is bolted. Holes are drilled on the columns and gusset plates, and supplied with matching plates.
Structural is assembled at site with welding
Advantages (660MW) of Bolting structure:oFast in erection.oClean environmentoNo Welding network requiredoSafety at siteoPainting finish is good o( No Weld surface)
b.No Welding work involved in assembly/ Erection , except Walkway rail post welding
Assembly is carried out with Welding
Can be dismantled if required ( For Maintenance purpose)
c
Material supply is tier wise including staircases, railing, gratings etc.
Material is supplied as per the erection sequence.
Erection completion tier wise, including gratings, platforms , staircases etc.
1 Cost of SG Package 1970.73 Cr 1020.54 Cr with ESP
2 Cost of ESP 183.54Cr
3 Total cost of Boiler + ESP 2154.27 Cr 1020.54 Cr
4 Cost of Boiler per MW with ESP 1.09 Cr 1.02 Cr
5 Cost of TG for entire stage 1204.72 Cr 634.31 Cr
6 TG cost per MW 0.6Cr 0.63 Cr
COST COMPARISON
BOILER SPECIFICATION
Description unit
S/H STEAM FLOW T/HR 2225
SH STEAM PR KG/CM2 256
SH STEAM TEMP 0C 540
RH STEAM FLOW T/HR 1742
RH STEAM TEMP INLET 0C 303.7
RH STEAM TEMP OUTLET 0C 568
RH STEAM PRESS INLET KG/CM2 51.17
FEED WATER TEMP 0C 291.4
Quoted Turbine Heat Rate
100% Load 1904 Kcal / KWH
80% Load 1924 Kcal / KWH
60% Load 1973 Kcal / KWH
50% Load 2065 Kcal / KWH
Net Plant Heat Rate = NTRH
= 2207 KCal / KWHR ( at 100% TMCR)
80% TMCR = 2222 Kcal / KWHR60% TMCR = 2276 Kcal / KWHR50% TMCR = 2376 Kcal / KWHR
Plant Efficiency at 100% TMCR = 38.96% 80% TMCR = 38.7 % 60% TMCR= 37.78% 50% TMCR = 36.19%
= Boiler Efficiency
100% TMCR 86.27%
80% TMCR 86.60%
60% TMCR 86.68%
50% TMCR 86.91%
SUPERCRITICALTHERMAL CYCLE
ADVANTAGES (1)
• Improvements in plant efficiency .
• Decrease in Coal Consumption
• Reduction in Green House gases.
• Overall reduction in Auxiliary Power consumption.
• Reduction in requirement of Ash dyke Land & Consumptive water.
SUPERCRITICAL – ADVANTAGES (2)
• Sliding pressure operation because of Once
through system .
• Even distribution of heat due to spiral wall
arrangement leading to less Boiler tube
failure, thereby improving system continuity
and availability of the station.
• Low thermal stress in Turbine .
• The startup time is less for boiler.
SUPERCRITICAL – DISADVANTAGES
• Higher power consumption of BFP
• Higher feed water quality required.
• More complex supporting and framing in Boiler due to
Spiral Wall tubes.
• Slight higher capital cost.
• Increased dependency For Spares and services.
IMPORTANCE OF EFFICIENCY
• The cost of operating the Plant of 3 x 660 MW, one percentage point below the design point, will incur additional fuel cost of Rs. 16 Crores in a year.
• The indirect costs for Maintenance, APC, Ash Dyke land etc. will give additional burden of Rs. 1Crores in a year.
• The environment will benefit on account of reduction in GHGs like Co2, NOX & SOX.
• The life time savings of Rs.550- 600 Crores can be achieved by increasing efficiency by one percentage .
• At Sipat, we gain an efficiency of 2.5 percentage by adopting super critical technology in 1980 MW station, thus saving Rs. 1440 Crores in its life time.
REDUCTION IN CO2 EMMISSION
• CONSIDERING AVG COAL CONSUMPTION OF AT FULL LOAD OPERATION : 400T/HR
• IMPROVEMENT IN EFFICIENCY
FOR SUPER CRITICAL TECHM
COMPARED TO 500 MW BOILER : 1.5%• REDUCTION IN COAL FLOW : 6 T/HR• REDUCTION IN CO2 EMMISSION
(FIXED CARBON CONTENT IN COAL 30%) : 6 T/HR • REDUCTION IN CO2 EMMISSION
PER YEAR : 52560 TONS