Energy analysis ,Exergy analysis, Environmental analysis of thermal power plants

1. (Simulation with Cycle-Tempo)
Presented by :-
Govind Kumar Mishra
Roll No.-14/ME/32
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2. 1. Introduction
2. Power Plant Configurations
i. SubC power plant
ii. SupC power plant
iii. USC power plant
3. Fuel Characteristics
4. Modelling of thermal Power Plant
5. Simulation of SubC power plant with Cycle-Tempo
6. Exergy destruction in power plant
7. Comparison among SubC, SupC and USC power plant
8. Conclusion
9. References
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3.  What does 3-E analysis mean ?
E
E
E
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4.  There are 3 basic power plant configurations
based on operating conditions:
1. Sub Critical power plant
2. Super Critical power plant
3.Ultrasuper Critical power plant
 These configurations are based on operating
temprature and pressure of power plant.
 Till now ultrasupercritical power plant is
limited to concept only.It is also known by the
name ‘The AD700 cycle’.
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5.  A typical SubC power plant has following
parameters:
 500MW/166.7 bar/537 C/537 C
 Final FW temp.253 C
 Single stage reheating
 3 LPFWHs and 2 HPFWHs
 Efficiency :36%-38%
 Boiler drum is needed
 1 single flow HP
1 double flow IP
1double flow LP used.
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6.  A typical SuperC power plant has following
parameters:
 660MW/242.2 bar/537 C/565 C
 Final FW temp. 280 C
 Single stage reheating
 4 LPFWHs and 3 HPFWHs
 Efficiency: 38%-40%
 No boiler drum needed
 1 single flow HP
1 double flow IP
2 double flow LP used.
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7.  Design parameters of a conceptual ultrasupC
power plant:
 430MW/350 bar/700 C/720 C
 It is also called ‘The AD700 cycle’.
 Final FW temp. 330 C
 Single stage reheating
 5 LPFWHs and 3 HPFWHs
 Efficiency:42%-43%
 No boiler drum needed
 1 single flow HP
1 single flow IP
1 double flow LP used.
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8.  There are mainly two types of coal used in
India.
1. Indian coal:Indian coal is high ash (HA) because it
consists of high amount of ash,minerals but low
quantity of fixed carbon(approax.40%).Its LHV
is15.2 MJ/kg and specific exergy is 17.3MJ/kg.
But in practice,plant efficiency is considered on
basis of HHV.Specific exergy of coal (EXcoal) is
estimated by :
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9. 2.Imported coal:It is generally low ash (LA) coal
as because it consists approax 70% fixed
carbon and less amount of ash or
minerals.Its LHV is 26.6 MJ/kg and specific
exergy is 28.5 MJ/kg.
 Sulphur content in both the coals are
comparable.
 Nitrogen content in imported coal is 1%
higher than Indian coal.
 Indian (HA) coal consumption is higher
than imported (LA) coal for same capacity of
power plant.
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10.  Assumptions made before carrying out
simulation are :
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11.  Governing equations used in this modelling
are:
 Where,
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12.  Performance parameters:
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13.  All the operating parameters are analysed
with Cycle_Tempo and effects of various
factors are carefully plotted,such as:
• Flue gas emissions w.r.t ambient pressure
• System efficiencies w.r.t ambient temperature
• System efficiencies w.r.t loading
• Efficiencies vs condender pressure
• Efficiencies vs excess air
• Efficiencies vs combustor pressure
• Efficiencies vs steam temperature
• Efficiencies vs cooling water temperature difference
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14.  It means on inceasing ambient pressure
SOx, NOx, CO2 emmissions decreases.
0
1
2
3
4
5
6
7
8
9
10
0 5 10 15 20 25
Emmissions(%)
Ambient pressure (bar)
Emission of SOx , NOx , CO2 in SubC power plant
SO2
NO2
CO2
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15. Above graph clearly tells that on high loading
working efficiencies of power plant is high.
0
5
10
15
20
25
30
35
40
0 20 40 60 80 100 120
Systemefficiencies(%)
Loading(%)
System efficiencies vs loading
Plant efficiency(%)
Exergy efficiency(%)
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16. Working efficiencies decrease as excess air %
is increased beyond 20%.
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33
34
35
36
37
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0 20 40 60 80 100 120
Efficiency(in%)
Excess air(in %)
Efficiencies vs excess air
Energy efficiency(%)
Exergy efficiency(%)
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17. It means upon decreasing
condenser pressure system
efficiencies increase.
Here upon increasing combustor
pressure efficiencies increase.
0
10
20
30
40
50
60
0 5 10Efficiency(in%)
combustor pressure(bar)
Efficiencies vs combustor
pressure
energy
efficiency(%)
exergy
efficiency(%)
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33
34
35
36
37
38
0 5 10 15
Efficiencies(%)
Condenser pressure(kpa)
Efficiencies vs condenser
pressure
Plant
efficiency(%)
Exergy
efficiency(%)
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18. On increasing cooling water
temperature gain efficiency
increases slightly.
But on incresing steam temperature
system efficiency increases
appreciably.
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33
34
35
36
37
38
0 10 20 30
Efficiency(%)
Cooling water temperature gain(C)
Efficiencies vs cooling eater
temperature gain
Energy
efficiency(%)
Exergy
efficiency(%)
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35
36
37
38
39
40
41
42
500 600 700
Efficiency(%)
steam tempreture(In c)
Efficiencies vs steam
tempreture
Energy
efficiency(%)
Exergy
efficiency(%)
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19. Thermal efficiency is maximum at
50% loading and decreses with
increase in loading.
2nd law efficiency or exergy efficiency is
also maximum at 50% loading and it
decreases with increase in loading
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20.  From 1st law analysis energy losses in condenser is maximum
about 55% of total input energy but due to its low grade
quality exergy destruction in condenser is only (20%-28%).
 Exergy destruction is highest is in turbine operating at
highest tempeerature.
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22.  System efficiencies are highest in USC and lowest in SubC
power plant.
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23.  Final feed water temperature is maximum in
USC and minimum in SubC power plant.
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24.  The thermal power plant has highest thermal and
exergetic efficiencies at 50% loading.
 The turbine has maximum exergy destruction and pump
the least,i.e at 50% loading exergy destruction is 46% in
turbine.
 The maximum energy loss is in condenser (57%) and
condenser together with feed water heater also accounts
for maximum exergy loss(52%) .
 There is reduction of (3%-5%) and (15%-17%) in emmision
of CO2,SOx and NOx in SupC and USC power plant in
comparison to SubC power plant.
 There is a substantial increase of 43% fuel consumption
and a significant decrease of 3% plant exergy efficiency
using HA coal as compared to LA coal.
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25.  ‘3-E analysis of pressurised pulverised combined
cycle(PPCC) power plant using high ash Indian
coal’ by Selvam Kalimuthu,Sujit Karmakar and
others: Energy 128 (2017) 634e648
 ‘3-E analysis of advanced power plant based on
high ash coal’ by M.V.J.j Suresh and others
 ‘Investigating theperformance of a steam power
plant’ by Ahmad Rashad and others
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