Diesel power plant

• 1. POWER PLANT ENGINEERINGDiesel power plant NAME: RISHABH KUMAR ENR No. 120260119116 BE Mech 5th SEM KALOL INSTITUTE OF TECHNOLOGY, KALOL

2. Power plant engineeringDiesel power plant INTRODUCTION:A generating station in which diesel engine is used asthe prime mover for the generation of electrical energyis known as diesel power stationDiesel power plants produce power in the range of 2 to50 MW.They are used as standby sets for continuity of supplysuch as hospitals, telephone exchanges, radio stations,cinema theatres and industries.They are suitable for mobile power generation andwidely used in railways , submarine & ships. 3. Applications of diesel power plant They are used as central station for small or medium powersupplies. They can be used as stand-by plants to hydro-electric powerplants and steam power plants for emergency services. They can be used as peak load plants in combinations withthermal or hydro-plants. They are quite suitable for mobile power generation and arewidely used in transportation systems such as automobiles,railways, air planes and ships. Now-a-days power cut has become a regular feature forindustries. The only solution to tide over this difficulty is toinstall diesel generating sets. 4. DIESEL ENGINE power plant 5. FIELD OF USEThe diesel electric power-plants are chiefly used in thefields mentioned below.1. Peak load plant: The diesel plants are used in combinationwith thermal or hydro-plants as peak load plants. This plant isparticularly preferable as peak load plant as it can be startedquickly and it has no standby losses as in the case of thermalplants where boilers always must be kept hot.2. Mobile plants: Mobile diesel plants mounted on skids ortrailers can be used for temporary or emergency purposes suchas for supplying power to large civil engineering works forsupplementing electricity supply systems that are temporarilyshort of power.3. Stand-by Units: This can be used as a standby unit to supplypart load when required. For example, this can be used withhydro-plant as stand-by unit. If the water available is notsufficient due to reduced rainfall, a diesel station supply powerin parallel with hydro-station. The use is made temporarily tillthe water is available to take the full load. 6. 4. Emergency plant: The plants used for emergency purposes are at to standbyunits, normally idle but are used where power interruption would meanfinancial loss or danger in key industrial processes, tunnel lighting and operatingrooms of hospitals. They are also used for telecommunication and water supplyunder emergency conditions.5. Nursery station: When the diesel plant is used to supply the power to a smalltown in the absence of main grid and which can be moved to another area whichneeds power on a small scale when the main grid is available is known as"Nursery Station". The main grid cannot extend to every corner of the countrytill there is enough load. Many times the extension of grid is not possible due tothe constructional difficulties as in Assam. Diesel unit of small capacity can beinstalled to supply the load to a small town during the process of developmentand it can be removed to another required place till the main grid for tapping thepower is available.6. Starting stations: The diesel units are used to run the auxiliaries for starting thelarge steam plants.7. Central stations: This can be used as central station where the capacity requiredis small (5 to 10 MW). The limit is generally decided by the cost of the plant andlocal conditions regarding the availability of fuel and water, space requirementsand non-availability of the grid. Small supply units for commercial purposes andpublic utilities e.g.,, cinema hall, hospital and municipalities are commonly usedin practice. 7. Diesel power plants in INDIA As on July 31, 2013, and as per the Central ElectricityAuthority the total installed capacity of Diesel basedpower plants in India is 1,199.75 MW. Normally thediesel based power plants are either operated fromremote locations or operated to cater peak loaddemands. Here is some list of presently operatingplants. SOURCE: Wikipedia. 8. List of diesel power plants in INDIA 9. Layout of Diesel PowerPlant 10. GENERAL LAYOUT 11. Diesel power plant- video 12. Simple layout 13. Essential elements of Diesel PowerPlantEngine SystemStarting SystemLubrication SystemFuel SystemAir filter and SuperchargeCooling SystemExhaust SystemGoverning System 14. Engine system ENGINE: This is the main component of the plantwhich develops required power. The engine is generallydirectly coupled to the generator Generally classified as two stroke engine and four strokeengines. 15. Diesel Engine-18 cylinder inline. 16. Industrial GenSet 17. Engine and Air intake systemEngine- This is the main component of the plant which developsthe required power. The electrical generator is usuallydirect coupled to the engine.Air intake system- The air intake system conveys fresh air through pipes orducts to (i) air intake manifold of 4 stroke engine (ii) Thescavenging pump inlet of a two stroke engine (iii) Thesupercharger inlet of a supercharged engine. 18. Air filter and supercharger Air filter is used to remove the dust from the airwhich is taken by the engine. The supercharger is used to increase the pressureof the air supplied. 19. Air intake system Air is first drawn through a filter to catch dirt or particlesthat may cause excessive wear in cylinders. Filters may beof following types: Dry type (paper, cloth, felt, glass wool etc) Wet type (oil impingement type, oil bath type where oilhelps to catch particles) Following precautions should be taken while designing airintake systems 20. Following precautions should be takenwhile designing air intake systemsAir intake should be located outside the engine room.Air intake should not be located in confined places toavoid undesirable acoustic vibrations.Pressure drop in the air intake line should beminimum to avoid engine starvationAir filters should be accessible for periodic cleaning.In some cases a muffler may be introduced to preventengine noise from reaching outside air. 21. Starting system The function of this system is to start the enginefrom cold by supplying compressed air at about17 bar supplied from an air tank is admitted to afew cylinders making them work likereciprocating air motors to run the engine shaft.Fuel is admitted to the remaining cylinders andignited in the normal way causing the engine tostart. 22. Lubrication system It includes the oil pumps, oil tanks, filters, coolersand connecting pipes. The purpose of the lubrication system is toreduce the wear of the engine moving parts Part of the cylinder such as piston , shafts ,valves must be lubricated. The lubricant iscooled before recirculation. Lubrication also helps to cool the engine 23. The following are the importantfunctions of a lubrication system LUBRICATION: To keep parts sliding freely past eachother, reducing friction and wear. COOLING: To keep surfaces cool by taking away partof the heat caused by friction. CLEANING: To keep the bearings and piston ringsclean. SEALING: To form a good seal B/W the piston ringsand cylinder walls. REDUCING NOISE: to reduce the noise of the engineby absorbing vibration. 24. oil tank 25. Fuel system It includes the storage tank, fuel pump, fuel transfer pump, strainersand heater. Pump draws diesel from storage tank to day tank through the filter The day tank is usually placed high so that diesel flows to engineunder gravity. Diesel is filtered before being injected into the engine by the fuelinjection pump.strainers 26. The fuel injection system performsthe following functions Filter the fuel Meter the correct quantity of the fuel to be injected Time the injection process Regulate the fuel supply Secure fine atomization of fuel oil Distribute the atomized fuel properly in the combustionchamber Oil is atomized either by blast or pressure jet.In pressure jet atomization oil is forced to flowthrough spray nozzles at pressure above 100 bar. It isknown as solid injection 27. Classification of solid injectionsystems Common rail injection system: The system isnamed after the shared high-pressure (100 to 200bars)reservoir (common rail) that supplies all thecylinders with fuel. With conventional diesel injectionsystems, the fuel pressure has to be generatedindividually for each injection. With the common railsystem, however, pressure generation and injection areseparate, meaning that the fuel is constantly availableat the required pressure for injection. Individual pump injection system: Distributor system: 28. CRDI 29. FuelInjector 30. Individual pump InjectionSystem 31. Individual pump InjectionSystem The schematic isshown in fig. An individual pump orpump cylinderconnects directly toeach fuel nozzle. Metering and injectiontiming controlled byindividual pumps. Nozzle contains adelivery valve actuatedby the fuel pressure. 32. Distributor System 33. Distributor System The schematic isshown here. The fuel is meteredat a central point. A pump meters,pressurizes andtimes the fuelinjection. Fuel is distributed tocylinders in correctfiring order by camoperated poppetvalves which admitfuel to nozzles. 34. Cooling system The cooling systemconsists of a water source,pump and cooling towers.The pump circulates waterthrough cylinder andhead jacket. The watertakes away heat form theengine and it becomes hot.The hot water is cooled bycooling towers and recirculated for cooling. 35. Cooling system The temperature of the hot gases inside the cylinder maybe as high as 2750 c . If there is no external cooling, thecylinder walls and piston will tend to assume the averagetemp. of the gases. Cooling is necessary because: To avoid deterioration or burning of lubricating oil. The strength of the materials used for various engine partsdecreases with increase in temperature. Local thermalstress can develop due to uneven expansion of variousparts. Increase in pre-ignition and knocking Due to high cylinder head temp. the volumetric efficiencyand hence power O/P of the engine are reduced. 36. cooling system 37. Elements of cooling system 38. There are two methods of coolingI.C. engines:1.Aircooling.2. Liquidcooling 39. Air cooling : In this method, heat is carriedaway by the air flowing overand around the cylinder. Fins are added on the cylinderwhich provide additional massof material for conduction aswell as additional area forconvection and radiativemodes of heat transfer 40. Liquid cooling In this method, thecylinder walls and headare provided withjackets through whichthe cooling liquid cancirculate. The heat is transferredfrom the cylinder wallsto the liquid byconvection andconduction. The liquid gets heatedduring its passagethrough the coolingjackets and is itselfcooled by means of anair cooled radiatorsystem. 41. Types of Water Cooling System Thermo SiphonSystem In this system thecirculation of water isdue to difference intemperature (i.e. difference indensities) of water. Soin this system pump isnot required but water is circulatedbecause of densitydifference only. 42. Pump CirculationSystem In this systemcirculation of wateris obtained by apump. This pump is driven by means ofengine output shaftthrough V-belts. 43. Exhaust system 44. Exhaust system This includes the silencers and connecting ducts. The exhaust gases coming out of the engine isvery noisy. silencer (muffler) is provide to reduce the noise. 45. Exhaust system Exhaust pipe leading out of the building should beshort in length with minimum number of bends toprovide as low a pressure loss as possible. Flexible tubings may be added in exhaust pipe to takecare of misalignments and expansion/contraction andalso to isolate the system from engine vibrations. 46. Exhaust system Each engine should have its independent exhaustsystem. Where possible, exhaust heat recovery should be madeto improve plant thermal efficiency. E.g., air heating,low pressure steam generation in diesel-steam powerplant etc 47. Governing system The function of the governing system is tomaintain the speed of the engine This is done generally by varying fuel supply tothe engine according to load. It is achieved with use of governors. 48. ADVANTAGES AND DISADVANTAGES OFDIESEL POWER PLANTDISADVANTAGES-> High running charges dueto costly price of Diesel Generates small amount ofpower Cost of lubrication very high Maintenance charges aregenerally high Noise problem Capacity is restricted.Cannot be of very big sizeADVANTAGES-> Simple design & layout of plant Occupies less space & is compact Can be started quickly and picksup load in a short time Requires less water for cooling Thermal efficiency better that ofSteam Power Plant of same size No ash handling problem Less operating and supervisingwork is required 49. THANK YOU ALL!!!