Egypt - South Helwan 3x650 MW Supercritical Thermal Power Plant ...
OVERVIEW OF SUPERCRITICAL THERMAL POWERPLANT , DPSTS
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Transcript of OVERVIEW OF SUPERCRITICAL THERMAL POWERPLANT , DPSTS
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Welcome
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OVER VIEW OF 2*800 MW SRI DAMODARAM SANJEEVAIAH THERMAL
POWER STATION
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contents
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Location Nellore, Andhra
Pradesh
Status Under Construction
Construction cost 8432/- crores
Owner(s) APPDCL
Operator(s) APGENCO
Primary fuel Coal-fired
Units operational 1*800 MW
Name plate capacity 1600 MW
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Fuel
• Domestic washed coal & imported coal in 70:30 ratio with 27.5% Ash
• GCV(gross calorific value) of 4,800 kCal/kg shall be used as a fuel during normal operation
• LDO(light diesel oil) as well as HFO(heavy fuel oil) shall be used as a startup as well as support fuel
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Fuel • Coal is mined from Kalinga ghat , Talcher Coalfield,
Angul district , Orissa
• shipped to krishnapatnam port by MGR trains and Coal barges and loaded to conveyer belt by stacker
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stacker
Fuel
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Pulverisation Fine powder of coal ,grinded by millers is fed
into furnace by hot air(primary air). Secondary air is fed into furnace to complete
combustion. Amount of primary air depends on load(>3%) High thermal efficiency Better control over load fluctuations Free from clinker and slagging troubles
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MILLSA Mill is a mechanical device for the grinding coal upto
desired finenessThere are 6 mills , located adjacent to furnace at ‘0’ M
level
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Furnace• Tangential firing-flame envelope rotates ensuring
through mixing within the furnace
• Heat energy is transferred through radiation (80%) and convection(20%).
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Furnace
• Heat generating rates of 1.5x 106 kJ/m3/hr can be achieved
• Maximum amount of coal can be achieved with min . space and time
• Through tip(vertical arc) temperature can be varied upto 1000c
• So constant superheat temperature can be maintained
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Ash handling plant
• Ash generated is about 30-40%of fuel consumption.
• Must be removed time to time • due to hotness , difficult to handle
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Bottom ash removal system• Non combustible residue of combustion of furnace is
bottom ash• Bottom ash falls from furnace to ash sluice trench and discarded to ash pond after mixing with water
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Electrostatic precipitator An ESP is a filtration device that removes fine
particles from a flowing gas using the force of an induce electrostatic charge minimally impeding the flow of gases through the unit.
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Electrostatic precipitator• Dirt particles are negatively charged
• They are attracted to the positively charged plates and stick there
• From time to time, the collecting plates are shaken to empty away the soot (rapping mechanism)
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ESP
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• collected in ESP hoppers
• We have 8X8 hoppers
Fly ash removal system
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Fly ash removal system• Pneumatically send to silo and then to trucks• Fly ash is used in 1.production of cement clinkers, concrete, ceilings 2.structural fills , agricultural purposes, floor etc
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Water treatment plant
• Through ion exchange process , RO and filtration by resin beds water is demineralised
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Water treatment plant
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DEMINERALISED(DM) Waterparameter valueConductivity <0.2 μS / Cm at 25 Deg.C
pH value 9 - 10 at 25 Deg.c
Total silica <0.02 ppm as SiO2
Iron as Fe Not detectable as per ASTM methods
Free CO2 ppm (as CO2 )
“
Total Hardness “
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Sea water
PARAMETERS AS VALUE
pH - 7.6
Turbidity NTU 10
P-alk / M- alk as CaCO3 ppm 98
Ca hardness as CaCO3 ppm 1100
Mg hardness as CaCO3 ppm 5050
Chloride as Cl % 1.89
Silica SiO2 ppm 3.8
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Babcock and Wilcox boiler• Boiler is a device for generating steam for power,
processing and heating purposes• Supercritical boiler operates above critical point
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Supercritical boiler• steam turbine efficiency improves significantly
compared to the typical subcritical cycle.
• The load change rate capability of the system is not restricted by the turbine
• Steam temperature at the inlet and outlet of the reheater is nearly constant over a wide load range
• The boiler feedwater pump power is significantly reduced at lower loads
• Short startup times
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Classification Supercritical boiler
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UP
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Universal Pressure (UP®) boiler.• The original B&W boiler for supercritical applications was the
Universal Pressure (UP®) boiler. • These boilers, nine of which are in operation, are among the largest
capacity fossil fuel boilers in the world. SPECIFICATIONS• Capacity, steam output: 700,000 lb/h (90 kg/s)• Pressure: Subcritical, usually 1800 to 2400 psi throttle pressure with 5%
overpressure capability. • Superheater and reheater outlet temperatures: 538 to 566C • Fuel:Pulverized coal.
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SWUP
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Spiral Wound Universal Pressure Boiler
• Designed for both base load and variable pressure load cycling operation as well as on-off cycling operation.
• The unique feature of this boiler, compared to other boilers, is that the tubes in the furnace, from the lower furnace inlet headers to a location near the furnace arch, are wound around the furnace circumference rather than being vertical.
• This design allows the fluid in the tubes to pass through the various heat flux zones around the furnace providing a more uniform outlet enthalpy.
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Spiral Wound Universal Pressure Boiler
SPECIFICATIONS• Capacity, steam output: From 2,000,000 lb/h (252 kg/s) to more than
10,000,000 lb/h (1260 kg/s).
• Operating pressure: 3500 psi (24.1 MPa) throttle pressure with 5%
overpressure; higher pressures available.
• Superheater steam temperatures: As required, currently in the 595C range.
• Fuel:Pulverized coal.
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Vertical Tube Universal Pressure Boiler
• A once-through boiler, applied to systems with a capacity of 400 MW or larger
SPECIFICATIONS
• Capacity, steam output: 252 kg/s to more than 1260 kg/s. • Operating pressure: 3500 psi throttle pressure with 5% overpressure;
higher pressures available. • Superheater steam temperatures: currently in the 595C range. • Fuel:Pulverized coal.
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BOILER
Main steam flow..........2600 T/hr SH steam press..............255 kg/cm2 (g) SH steam temp..............568° C Feedwater temp............307° C RH steam flow...............2052 T/hr RH steam press.............57.8 kg/cm2 (g) RH steam temp..............596° CHeight............................
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BOILER
Fuel Design RangeGCV, kCal/kg 4800 4000-5000
Moisture, % 9.5 6.0-20.0
Ash, % 27.5 25.0-34.0
Volatile matter,% 28.5 20.0-33.0
Fixed carbon,% 34.5 24.0-40.0
HGI 50 5-55
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Boiler accessories Economizer Waste heat of the flue gases is utilized for heating the
feed water Air Pre-heater Transfers heat from flue gases to primary/secondaryAir by means of rotating heating surface elements
Super heater Increases the temperature of the steam above its
saturation point
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Boiler accessories P.A.Fan (two per unit-50% capacity each) designed for handling atmospheric air upto a
temperature of 500c
F.D.Fan (two per unit-50% capacity each) designed for handling secondary air for the boiler
I.D.Fan (two per unit-50% capacity each) 1. located between ESP and chimney. 2.used for sucking flue gas from furnace
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Boiler accessories• SCR technology 1.Converts NOX into N 2 and water . 2.Anhydrous/aqueous NH3 or urea is added to
stream of ………flue gases and is adsorbed onto a catalyst
4NO + 4NH3 + O2 → 4N2 + 6H2O
3.They reduce NOx by 70-95%
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SCR
• SCR incorporating Ammonia Injection Grid (AGI) and IsoSwirl Mixing system
economizer
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Steam Turbine• Being a form of engine , requires in order to function a
suitable working fluid a source of high grade energy and sink of low grade energy
Low presure module of sft 100 alstom
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Steam Turbine• Greater heat drop• Absence of internal lubrication(no filters)• Develops many times the power compared to
reciprocating engines
3 stage turbine(tandem compounded)
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Steam Turbine• The cylinder(stator) contains fixed blades , vanes and
nozzles that direct steam into moving blades(rotor)
• The rotor are completely enclosed in a alloy steel outer case (one capable of withstanding high pressures and temperatures).
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Steam Turbine• The rotor of large steam turbine consists of large ,
intermediate and low pressure sections.• change in direction of motion gives rise to a change of
momentum or force• this is driving force of the primemover
Four Cylinder Turbines
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Turbine name plate details
Output 800,000kW Speed 3000rpm HP STEAM PRESS. 24.2MPa(a) HP STEAM TEMP 565 deg
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Cooling tower(hyperbolic)
• Required when positive control of temperature is required
• Rate of evaporation of water depends on 1 amount of water surface area exposed 2 time of exposure and R .H of air 3 (inlet air WBT-water inlet temperature)
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Cooling tower(hyperbolic)• It is necessary to precool the hot water from condenser
So (Two-Ts ) Is high • Vacuum at condenser can be maintained
• It comprises of 30% of budget
• Due to large base , withstands hurricanes
• No fanes are needed
• Chimney shape creates it own draught • No Ground fogging and warm air recirculation
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Cooling tower(hyperbolic)• Height = Plan------circular• Diameter= Profile---hyperbolic
• (inside)
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Cooling tower(hyperbolic)• Steel reinforced concrete structure
• Mostly hollow inside• Bottom is 10m above air-intake
• Force causing air to flow F=H(w0-wi)
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Active power – 604.35MWReactive power – 46.35MVAR
Generator kV : R-Y – 24.32kV : Y-B – 24.32kV : B-R – 24.23kV Generator Amps : R-ph – 14.14kA : Y-ph – 14.33kA : B-ph – 14.61kA
Frequency : 49.97Hz P.F : 1.00
GENERATOR PARAMETERS
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FIELD PARAMETERS
• Field voltage : 288.33V• Field current : 3452.6A• Rotor temperature : 65.13’c• POS 90R(AUTO) : 101.36%• POS 70E(MANUAL) : 147.89%
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Fig. 19 Switchyard
Switchyard is a part of electrical generation, transmission and distribution
system.
Switchyard generally have circuit breakers, CT’s ,PT’s, Bus bars,
Transformers, Protection control equipments, Switches etc.,.
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Fig. 20 Circuit Breaker
Circuit breaker: A circuit breaker is an automatically operated electrical
switch designed to protect an electrical current from damage caused by
overload or short circuit. The basic function of CB is to detect a fault
condition and, by interrupting continuity to immediately discontinue
electrical flow.
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Fig. 21 Lightning arrester
Insulators: The insulators provide necessary insulation between line
conductors and supports and thus prevent any leakage current from
conductors to earth.
Lightning Arrester: It is a device used on electrical power systems and
telecommunication systems to protect insulation and conductors of the
system from the damaging effects of lightning.
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Fig. 22 Voltage transformer
Voltage transformer: These are necessary for isolating the protection,
control and measurement equipment from the high voltages of the power
system. These are used to supply appropriate values of voltages to the
equipment.
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Fig. 23 Current transformer
Current transformer: To feed the current circuits in protection systems
employing secondary relays current transformers are used.
Bus coupler: Two different bus sections of two different power
transformers are connected by means of a bus coupler.
Relay: It gives a tripping signal in case of any irregularity or faults.
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Thank you by
HARSHA.S