ppt final year
TRANSCRIPT
A SEMINAR PRESENTATION
ON SUMMER TRAINING
FROM
HINDUSTAN ZINC LIMITED
MADE BY:KALYAN GORAI4TH YR.,MECHANICAL
HINDUSTAN ZINC LIMITED
CHANDERIYA LEAD ZINC SMELTER(CAPTIVE POWER PLANT)
• A power plant is an industrial facility for the generation of electric power. The power produced in Hindustan Zinc Limited is for its own production purposes, and is known as a Captive Power Plant (CPP).
• While supplying uninterrupted and reliable power to Chanderiya Lead Zinc Smelter, the CPP has been additionally wheeling power to its Agucha, Debari and Dariba units of Hindustan Zinc Limited.
• Recently sale of power has also been initiated with both RSEB and power exchange.
• Captive Power Plant in Chanderiya consists of 3 units (2X77 MW + 1X80 MW)=Total of 234 MW.
INTRODUCTION
• Disturbances in taking power from grid.
• Grid power distribution is unreliable both in quality and quantity.
• Taking power from grid is much more expensive as compared in generating its own power i.e. SELF GENERATION –CPP.
• Cost of grid power Rs./kWh 4.50 to 5.50
• Cost of Captive Generation Rs./kWh 2.00 to 2.50
NEED OF CPP
BOILER CLASSIFICATION & CPP SPECIFICATIOS :
MAKE & YEAR: : BHEL,2004
Acc to application : Utility boiler
Acc to operating pressure : Sub-Critical (Re-circulation type)
Acc to fuel : Solid fuel (pulverised fuel firing)
Acc to draft : Balanced draft
Acc to circulation : Natural circulation
Acc to pass : Two pass (outdoor type)
Acc to firing : Tangential firing
Acc to pressure : High pressure
Acc to position : Vertical
Acc to support : Top supported with buck stay
TECHNICAL SPECIFICATIONS
• Type of Turbine : High press, high Temp Impulse-Reaction• Rotation Speed : 3000rpm• Rated Power : 77MW• Main steam inlet pressure : 90 kg/cm²• Rated steam flow inlet : 286.4 T/hr• Stage of heaters : 2LP, 1 De-aerator & 2HP• Heat Rate : 2640 kcal/ kwhr
Turbine Specifications
Thermal power stations produce electricity by burning fuel in a boiler to heat water to produce steam. This steam at high pressure rotates the blades of a turbine which spins a generator to produce electricity. The steam is further cooled in a condenser to form water and sent again to boiler.
Thermal Power Station
BOILER
BOTTOM ASH HOPPER
ASHSILO
ASH PUMP
ESP
IDFAN
ASHDYKE
AIR PRE -HEATER
FD FAN
DISPOSAL -- ACC
CHIMN
EY
BUNKER
HOT PA FANFEEDER
PULVERISER
TURBO ---GENERATOR
CONDENSER
BFP
HP HEATER
DEAERATOR
CT
CW PUMP
LP HEATER
CEP
COAL YARD
RESERVOIRDM PLANT
FILTERDM TANK
POWER
COAL TO ELECTRICITY
CRUSHER
1) BOILER AND AUXILIARIES.
2) TURBINE,GENERATOR AND AUXILIARIES.
3) ESP (ELECTROSTATIC PRECIPITATOR)
4) COOLING TOWER
5) DE-MINERALISING PLANT
MAJOR COMPONENTS
Furnace Water wall tubes Pressure Parts
Drum Super heaters Reheaters Economizers
Air pre heaters Soot Blowers Coal Bunkers and feeders Pulverizes Coal Piping Burners Igniters & warm-up Burners Duct work Insulation and Legging
BOILER OVERVIEW
1) Boiler Terminology
• Furnace is the primary part of boiler where the chemical energy of fuel is converted to thermal energy.
• Furnace is incorporated with water wall tubes where water is evaporated to steam.
• TYPES OF WATER WALL TUBES :
1. Tangent tube wall : Tubes are closely attached
from the panels.
2. Membrane wall : Tubes are welded together
by means of metal strips.
Furnace & Water Wall Tubes
• Superheaters are provided in the boiler to raise the steam temperature above the saturation temperature by absorbing heat from flue gas.
ADVANTAGE:
1. By increasing the temperature of steam useful energy can be recovered thereby increasing efficiency of cycle.
2. It eliminates condensation of steam in pipelines, thus avoiding erosion of blades.
TYPES OF SUPERHEATERS :• Radiant Superheaters :The superheaters placed above
the furnace which can view the flame.• Convective Superheaters : The other surfaces are called
convective type.
SUPERHEATER
• REHEATER is used to raise the temperature of steam from which part of the energy has been extracted in high pressure turbine.
• By reheating efficiency can be increased which increases with number of stages.
• Single reheating is usually applied for capacity above 100MW & 2 reheat above 500MW.
DESUPERHEATER :• This is located between two superheater header and
the steam flows through it. Water of high quality is introduced into the superheated steam through a spray nozzle at the throat of a venturi section which mixes and cools the superheated steam. By regulating the water spray steam temperature can be easily controlled.
• The spray water will normally obtained from feed water line after the HP heaters and before feed regulation station.
REHEATERS & DE-SUPERHEATERS
• An Economiser absorbs heat from the flue gases and add this as sensible heat to the feed water before water enters the evaporative circuit of boiler.
• Feed water is supplied to economiser inlet header via feed stop and check valves.
• Flow of feed water is upward through the economiser that is counter flow to flue gases & from outlet header feed water is led to steam drum.
• By recovering heat from flue gases and supplying it to feed water it increases efficiency in steam generation or in other words saves fuel.
ECONOMISERS
• APH is a heat exchanger in which air temperature is raised by transferring heat from other fluid such as flue gases.
• Stability of combustion is improved by use of hot air.
• Less unburnt flue particles in flue gas.• In case of pulverised coal combustion ,hot air can be
used for drying the coal as well as for transporting the pulverised coal to burners.
TYPES : 1. Recuperative Type : Heating medium is on one side
& air is on the other side of tube /plate & heat transfer is by conduction
through the material which separates the media. 2. Regenerative Type : Heating medium flows
through a closely packed rotating matrix to raise its temperature and then air is
passed through the matrix to take up the heat.
AIR PRE HEATER(APH)
REGENERATIVE TYPE(APH)
• PA (Primary air fan) : These are the high pressure fans which supply the air needed to dry & transport coal either directly from the coal mills to the furnace or to the intermediate bunker.
These fans are usually of the radial aerofoil type.
• FD (Forced draft fan) : These fans supply the air necessary for fuel combustion and must be seized to handle the stoichiometric air plus the excess air excess air needed for proper burning of the fuel.
These fans are usually of the radial aerofoil or variable pitch axial type.
• ID (Induced draft fan) : These fans evacuate combustion products from the boiler furnace in atmosphere through stack by creating sufficient negative pressure .
FANS
• Rated Power : 77 MW• Rated Voltage : 11.5 kV• Rated Current : 4800 A• Rated Speed : 3000 rpm• Power Factor : 0.8 lag• Rated Frequency : 50 Hz• Efficiency : 98.5%
Generator Specifications
2) TURBINE
• Turbine is a Prime Mover Which Converts “Thermal Energy Of Fuel Into Mechanical Energy”.
• Steam is allow to expand through narrow orifice, it assumes kinetic energy at the expenses of enthalpy, this kinetic energy is converted into mechanical energy through the impluse or rection of steam against the blade.
• Steam moves continuously through blades as a result Centrifugal pressure exerted on the blade.
• TOTAL MOTIVE FORCE =
CENTRIFUGAL FORCE + CHANGE OF MOMENTUM (ROTATIONAL ENERGY)
Principle Of Turbine
Turbine are Multistage
NAME• CONDENSER
• MAIN AIR EJECTOR
• CW PUMPS
FUNCTION Condense the steam & maintain the
vacuum at the exhaust of LP Turbine.
Main the vacuum by extracting the non condensable gases from the condensate.
To circulate cooling water through condenser tubes for cooling the system.
Turbine Auxiliaries
NAME• CEP
• LPH
• DEAERATOR
FUNCTION Extract condensate from condenser
hot well & passes it to deaerator.
To raise the temperature of condensate by transferring heat taken from turbine extraction.
To remove dissolved gases from feed water by increasing there temperature with pegging steam taken from APRDS.
Turbine Auxiliaries
NAME• BFP
• HPH
• OIL PUMPS1. MAIN OIL
PUMP(MOP)
FUNCTION To pump the feed water from
deaerator to Boiler (Economiser) at a very high pressure.
Before going to boiler it is again heated by turbine extractions.
To supply lube oil & control oil during “Normal operation of Turbine”.
Turbine Auxiliaries
NAME
2. AUXILIARY OIL PUMP (AOP)
3. EMERGENCY OIL PUMP (EOP)_
4. JACKING OIL PUMP (JOP)
FUNCTION
To supply lube & control oil during “ Start up & Shut down of Turbine ”.
To supply lube oil to bearings during “ AC failure ”.
For lifting turbine shaft during startup & shut down.
Turbine Auxiliaries
TURBO GENERATOR
A Generator is an electromechanical device that converts mechanical energy to alternating current electrical energy by using a rotating magnetic field. Any AC generator can be called as an Alternator.
POWER OUTPUT OF TURBO GENERATOR :P D2 . L . B . A . n
P : Power in MVAD : Bore Diameter of Core in metersL : Length of Active Rotor Body in metersB : Air Gap Flux Density in TeslaA : Stator Ampere-Turn Loading in Amp./metern : Speed in rpm
• ,
DEFINITION
Stator
Stator Core
Rotor
Bearing
Shaft Seal
Terminal Bushing
Oil Catcher
Cooler
InsertCover
MAIN PARTS OF TURBO GENERATOR
Stator End Winding Assembly
Rotor Body
Rotor Fan Blades
•Magnetizes the rotor poles and creates the required magnetic intensity for stator conductors thereby developing the stator voltage .
•Regulates terminal voltage of the machine.
•Meet excitation power requirements under all normal operating conditions.
•Enables maximum utilization of machine capability.
•Guard the machine against inadvertent tripping during transients.
•Improve dynamic & transient stability thereby increasing availability.
Excitation System
3) ESP
An electrostatic precipitator is a Device which removes dust or other finely divided particles from flue gases by charging the particles inductively with an electric field, then attracting them to highly charged collected plates.
ESP
FUNDAMENTAL PARTS OF ESP:
•Casing•Hopper•Gas Distributor Screen•Collecting System•Emitting System•Rapping Mechanism of collecting system•Rapping Mechanism of Emitting System•Insulator Housing
• Removal of dirt from flue gases in steam plants.• Cleaning of air to remove fungi and bacteria in
establishments producing antibiotics and other drugs.
• Cleaning of air in ventilation and air conditioning systems.
• Removal of oil mists in machine shops and acid mists in chemical process plants.
• Cleaning of blast furnace gases. • Recovery of valuable materials such as oxides of
copper, lead, and tin. • separation of rutile from zirconium sand.
Application of ESP
4) COOLING TOWER
• Cooling tower is an application where the plant heat exchangers are cooled with water.
• The pump keeps the water re-circulation through the heat exchangers where it picks up heat and distributes on to the cooling tower. The heat is released from the water through evaporation.
• The cold water enters the heat exchangers for cooling. The resulting hot water from heat exchangers is sent to cooling tower.
• The cold water exits the cooling tower and is sent back to the exchangers for cooling.
• Make up water source is used to replenish around 2 % of water lost due to evaporation and drift.
Definition
ATMOSPHERIC NATURAL
DRAFT
MECHANICAL DRAFT
AIR COOLED
CONDENSER
AIR COOLED HEAT
EXCHANGER
Classification Of Cooling Tower
Natural draft cooling towers :• Distinct shape much like a tall cylinder,it operates on a chimney principle that
allows air movement on density differential.• Such towers have the advantage of not requiring any fans, motors,gear boxes
etc.• Due to the tremendous size, these type of towers are used only for very high
flow rates.Mechanical Draft cooling towers.• These are more widely used. These towers utilize large fans to force air
through circulating water.• The water falls downward over fill surfaces which help increase the contact
time between the water and the air.This helps maximize heat transfer between the two.
Types of cooling tower
De- Mineralization System consisting of:-
• PSF (PRESSURIZED SAND FILTER)• ACF (ACTIVATED CARBON FILTER)• SAC (STRONG ACID CATION EXCHANGER) • DEGASSER• WBA (WEAK BASE ANION EXCHANGER . • SBA (STRONG BASE ANION EXCHANGER). • MB (MIX BED).• UF FILTER
De-Mineralization (DM) is the process of Removing mineral salts from water by using the Ion Exchange process which produces water with high quality & purity that used in “Boiler as a Feed Water”.
6) DE-MINERALISING PLANT
Raw waterpond
Clarifier CWST
DEGASSER.
Goshunda Dam
Alum Dosing For coagulation
Poly Dosing For Flocculation
Chlorine Dosing For Killing Bacteria & Algae
For Storage
Remove Dead Suspended Particles
Remove Odour & Organic Matters
Remove Cations e.g.
Ca+,Mg+,Na+.
REMOVAL OF CO2
Remove Carbonates & Bi-carbonates
Remove Anions e.g.
Cl-,SO4-.
HOTWELL
DMST
A
B
TO CST
Hot well make up pumps
Remove Remaining Silica:PH: 6.8-7.0Cond.:<1.00ųS/cmSilica:0.02ppb
Membrane Filter to Remove Colloidal Silica
From SBA
7)COAL HANDLING PLANT
Overview Of CHPCOAL Transportation by RAIL
Through wagon Tippler
Apron feeder
Vibrating type
non vibrating type
Primary crusher house
Reduced size from 600mm to 100mm
SECONDARY CRUSHER
HOUSE
Reduced size from 100mm to 20mm
MAGNETIC SEPRATOR
Separate magnetic particles i.e. iron
Vibrating screen
Allow only 20mm sized coal
RECLAIM HOPPER
Through belt
conveyor
COAL DRIER
Through Tippler
COAL BUNKER
PULVERISER TO BURNERS
Wagon Tippler Bottom Discharge Wagon
Coal System
• Through Wagon Tippler the Raw coal is fed to primary crusher house via belt conveyor where the size of coal is reduced from 600mm to 100mm. Magnetic separator, separates the iron particles & then to secondary crusher house for further reduction of coal (20mm sized).
• Vibrating screen allows only 20mm sized coal to drier & through tippler or trolley ,it passes over to coal bunker & then pulverizers for further crushing through volumetric feeder .
• The Pulverized Coal is then mixed with primary air which carries the coal air mixture each four corners of the furnace burners.
8) ASH HANDLING PLANT
ESP
FLY ASH SILO
BULKER
Unloading
Plate valve
COM
PRESSOR
Compressed air
Fly ash
ASH HANDLING PLANT
ASH HANDLING PLANT
Fly ash is captured and removed from the flue gas by electrostatic precipitators located at the outlet of the furnace and before the induced draft fan. The fly ash is periodically removed from the collection hoppers below the precipitators. Generally, the fly ash is pneumatically transported to storage silos for subsequent transport by trucks.BOTTOM ASH SYSTEM
At the bottom of every boiler, a hopper has been provided for collection of the bottom ash from the bottom of the furnace. This hopper is always filled with water to quench the ash and clinkers falling down from the furnace. Some arrangement is included to crush the clinkers and for conveying the crushed clinkers and bottom ash to a storage site.