Industrial Energy Management
Industrial energy management
Fossile fired power plants: Construction elements
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Industrial Energy Management
Type of steam boilers
shell boilers
kettle boiler
flue tube boiler
fire tube boiler
fire-flue- tube boiler
fire-flue- tube boiler
angular tube boiler
(Holland type)
steep tube boiler
water-tuber boilers
steep tube radiation
boiler
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Industrial Energy Management
design of steam generators (boilers)
1 feed water inlet, 2 economizer, 3 steam drum, 4 evaporator,
5 distributor, 5 ash, 7 cóal and combustion air, 8 superheater,
9 fresh steam, 10 exhaust gas, 11 recirculation pump
12 moist separator (sediment bowl)
a: natural circulation boiler
b: forced circulation boiler
once-through forced flow boiler: c: Benson type, d: sulzer type
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Industrial Energy Management
design of steam generators, critical boiling events
1. Kind: DNB
Departure from nucleat boiling, excess of critical heat flux while nucleate
boiling
2. Kind: Dryout
Transition from annular flow to spray flow: steep decline of critical heat flux
3. Kind: Burnout
High steam content, minimal critical heat flux
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Industrial Energy Management
design of steam generators (boilers)
combination of forced circulation/once trough
moist separation: 17) steam drum
25, Fig. 3, 2) sediment bowl
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Industrial Energy Management
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Example steam boiler: Offleben
fresh steam
steam outlet
super
heating
intermediate super
heating
steam inlet
moist separator
residues evaporator
evaporator
bowl
support tubes
economiser
feed water
Benson type once-through forced flow boiler (Babcock,
Oberhausen)
with 1000t/h steam at 210 bar with 535°C(fresh) and 540°C
intermediate superheating
control scheme water and steam cycle Offleben
Industrial Energy Management
Example steam boiler: Mannheim
once-through forced flow) with 1370t/h steam
at 275 bar with 530°C(fresh) and 540°C
intermediate superheating
control scheme: a) steam and water, b) arrangement of
separators and bi flux heat exchangers
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Industrial Energy Management
temperature curve in steam generators
adiabatic combustion temperature
Air
ECO I
entrance
chimney
reheat. I
pre super heater
reheater II
super heater
evaporator
radiation zone
water steam
side
ash
ECO II
temperature / °C
flue gas temperature
amount of transfert heat (relative) /%
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Industrial Energy Management
ratio of transfered heat in boiler
ratio of heat / %
reheating 2
superheating
evaporation
feedwater preheating
fresh steam pressure / bar
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Industrial Energy Management
variation of the thermal efficiency / %
Efficiency improvement: condensation pressure/temperature
fresh steam conditon
condensation pressure / bar
condensation temperature / °C
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Industrial Energy Management
thermal efficiency / %
Efficiency improvement: temperature + pressure fresh steam
fresh steam pressure / bar
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Industrial Energy Management
variation of the thermal efficiency / %
Efficiency improvement: quantity of preheating stages
feed water temperature / °C
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Industrial Energy Management
variation of the thermal efficiency / %
Efficiency improvement: quantity of reheating stages
quantity of reheating stages
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Industrial Energy Management
power plant design
hp preheater 1
2
main pump
feed water tank
degasification
4
3
2
lp preheater 1
heat circuit diagram , 750 MW, black coal, Boxbach
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Industrial Energy Management
power plant design
water preheating
air preheating
regenerativ
processes
fuel
energy output
38%
el. mech.
auxiliary
losses 1.5% power2.5%
losses at boiler
9%
radiation
2%
losses at condenser
42%
Energy flux scheme in black coal fired thermal power plant
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Industrial Energy Management
power plant design, air preheating
flue gas
flue
gas
air inflow
air inflow
rotating storage
rotating
air hood
scheme for regenerativ air preheaters with a) rotating heat storage mass and
b) fixed storage mass
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Industrial Energy Management
power plant design, regenerativ air pre heating, type:
Rothemühle static heat storrage, air hood rotation max 1upm,
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Industrial Energy Management
power plant design, air preheating, type Ljungström
rotating storage mass, 1.5-4upm, D: up to 15m, M: 400-500t, A: 24000m²
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Industrial Energy Management
power plant design, emission reduction
dust
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Industrial Energy Management
power plant design, emission reduction
desulphurization: sulphur dioxide with quicklime to gypsum
2SO2+2Ca(OH)2+O2+2H2O
2CaSO4*2H2O
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Industrial Energy Management
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power plant design, emission reduction
nitrogen oxides NOx
avoidance T<1400°C
denitrification unit using
carbamite (urea)
4 NH3 + 4 NO + O2 → 4 N2 + 6 H2O
a) hot process (selective catalytic reaction)
b) cold process (reactor behind desulphurization)
ISUT-Seminar Jörg Sauerhering
3011.2012
Thanks for your attention!
sources:
H. Effenberger, Dampferzeuger
K. Kugeler, Energietechnik
T. Bohn, Band 5 Handbuchreihe Energie
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