3 Overview of coal handling plant Wagon tipplerRaw coal from bharat coal ltd. Dhanbad & bilaspur(MP)To SSTPS from gudla via a single railway trackbunkershoppersCrusher houseCoal mills(pulverization)Raw coal feedersBoiler furnace ( tangential firing of pulverized coal)
4 Steam Boiler 1.The utility boilers are large capacity steam generators used for the electrical power generation.2. In boiler heat energy is released from the combustionof fossils fuel and heat is transferred to differentfluids in the system.3. The boiler installed in S.T.P.S. are single drum,tangential fired water tube naturally circulatedover hanged, pulverizing coal firing with amax. Continuous steam output of 375 tons/hour at138 kg/cm2 pressure and 5400C temperature.4. Heat transfer section in boiler4.1 Furnace : Furnace is the primary element part of the boiler where the chemical is obtained by combustion.
5 Air from environment via draft fans BOILER:stackFlue gasesDM waterBoiler water tubes& various stagesSuper heated steamBoiler furnaceAir from environment via draft fansAsh handling plantPulverized coal
6 2.The major fuels used in the steam generation are coal oil and gas.3. In furnace the whole combustion region is surroundedby tubes through which water flows.BOILER AUXILLARIES4.2 SUPER HEATER: Superheats are meant to raise thetem. of steam by absorbing heat from flue gases steam them.2. Super heater eliminates the formulation of condensateduring transporting of steam in pipelines and inside theearly stages of turbine, which is harmful to the turbineblades and pipelines .3. Superheated steam is led into the H.P. turbine throughmain steam stop valve.After doing the useful works in the H.P. turbine the
7 steam is returned to reheater through the cold reheat lines. 4. The superheataer may be made in the form of coils andplatens.4.3 Reheater: Reheater are used to raise the temp. of steamfrom which point the energy had been extracted in H.P.turbine with increasing no. of reheating stages. Reheating iscontinuing till temp. of steam is reaches to 5400C.2. Superheaters and reheaters tubes are made of 50 to 75mm outside diameter.4.4 Economizer :The function of an economizer in a steam-generatingunit is to absorb heat from the flue gases and add this assensible heat to fed water. It acts like feed water heater.
8 The size of economiser tubes are 45 to70mm in outside diameter . The water flow must be uniform to avoid the steam formation in economiser.4.4Air Preheater:Air preheater is a heat exchanger in which preheating of air done by transferring heat from the flue gasbefore supplying to the combustion chamber.For better combustion the air temp.250to350 is always desired .The preheating of air results:1.Improved combustion2.Saving in fuel consumption3.Thermal efficiency.
9 Super heaters & reheater Flow of steamturbineBoiler drumBoiler tubesSuper heaters & reheatercondensereconomiserFWPDM water plant
10 Steam turbineTurbine is a prime mover in which a shaft is rotate by impact or reaction of stream of working substance ( steam, water, gases etc) upon blades of a wheel. It converts the potential or kinetic energy of the working substance into mechanical power by dynamic action of working substance. When the working substance is steam it is called the steam turbine. There are no. of blades alternatively fix & rotate due to which velocity is increased & pressure is decreased.Principle of operation : . The steam is caused to fall in pressure in a passage of nozzle: doe to this fall in pressure a certain amount of heat energy is converted
11 In to moving with a greater velocity. The rapidly moving particles of steam suffer a change in direction ofmotion which gives change of momentum and thereforeto a force.IMPULSE TURBINE: The passage of steam through movingpart of turbine in such a manner that the pressure at the outletside of the blade is equal to that at the inlet inside. Such aturbine is broadly termed as impulse turbine.IMPULSE REACTION TURBINE: Pressure of the steamat outlet from the moving blade may be less than that at theinlet side of the blades; the drop in pressure suffered by thesteam during its flow through the moving causes a furthergeneration of kinetic energy within the blades and adds to thepropelling force which is applied to the turbine rotor. Such aturbine is broadly termed as impulse reaction turbine.
17 High pressure turbine: The HP turbine consists of 25 reaction stages High pressure turbine: The HP turbine consists of 25 reaction stages. The moving and stationary blades are inserted into appropriately shapes into inner casing and the shaft.Intermediate pressure turbine: The steam from HP turbine after reheating enters the inner casing from above and below through two inlet nozzles.The IP turbine consists of 20 reaction stages per flow. The moving and stationary blades are inserted in appropriately shaped grooves in shaft and inner casing.Low pressure turbine: Steam admitted to LP turbine from IP turbine flows into the inner casing from both sides through steam inlet nozzles.
18 GENERATOR: TWO POLE TYPE; WITH CYLINDRICAL ROTOR ELECTRICAL ENERGYTWO POLE TYPE; WITH CYLINDRICAL ROTORBASIC PRINCIPLE :FARADAY’s LOW OF MAGNETIC INDUCTIONCOOLING:STATOR WINDING-DIRECT WATER COOLINGROTOR WINDING – HYDROGEN COOLINGMECHANICAL ENERGY