Industrial visit Report

On

PaRAS THERMAL POWER PLANT Akola

2016 - 17

Submitted by

1)Abhijeet Amnerkar 2) Amit Hinge

3)Bhushan khadse 4)Chandanlal Bahetwar

5)Dinesh Dakhore 6)Piyush Bhat

INDEX

Abstract

Introduction what is thermal power plant Schematic of thermal power plant Different elements of power station Coal Preparation Fans Boiler Superheater Turbine Generator Condenser Cooling Tower Boiler Feed Pump Ash Handling plant Thermal power plant operation Conclusion Reference

Acknowledgement

We express our feeling of gratitude to the Chief Engineer (C&O), Paras Thermal Power Station for granting permission to visit the plant. We are especially very much thankful to Mr. Hitesh Khapekar Assistant Engineer, who took great effort to share his practical knowledge to enhance the technical skill of

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the students. We would like to appreciate their concern for the technical upliftment of the students.We are very much thankful to Prof. Shailesh Watekar, HOD of Electrical Department for allowing and guiding for the proper execution of the visit. We are also very much thankful to the management of Agnihotri college of Engineering Nagthana Road, Wardha for allowing the visit.

Abstract

Paras Thermal Power Plant is oldest power plant of Ma-harashtra State Power Generation Company (Mahagenco) loc-ated at Paras, Akola district of Maharashtra. The power plant is one of the coal based power plants of MahagencoParas Thermal Power Station is the oldest of all Mahagenco Power plants. The station has witnessed the third generation technology. The sta-tion had 30 MW installed capacity in 1961 with a stroke boiler-Almost two third of electricity requirement of the world is ful-filled by thermal power plants (or thermal power stations). In these power stations, steam is produced by burning some fossil

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fuel (e.g. coal) and then used to run a steam turbine. Thus, a thermal power station may sometimes called as a Steam Power Station. After the steam passes through the steam turbine, it is condensed in a condenser and again fed back into the boiler to become steam. This is known as ranking cycle. This article ex-plains how electricity is generated in thermal power plants. As majority of thermal power plants use coal as their primary fuel, this article is focused on a coal fired thermal power plant.

Introduction

About Paras Thermal Power Plant :- Paras Thermal Power Plant is oldest power plant of Ma-harashtra State Power Generation Company (Mahagenco) loc-ated at Paras, Akola district of Maharashtra. The power plant is one of the coal based power plants of Mahagenco. Paras Thermal Power Station is the oldest of all Maha-genco plants. The station has witnessed the third generation technology. The station had 30 MW installed capacity Power in 1961 with a stroke boiler. The same unit we abandoned in 1993 due to ageing.It is on the Nagpur–Bhusawal section of Central Railway.Coal-based thermal power stations consume large quantities of coal.

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[3] For example, the Paras Thermal Power Station consumed 351,000 tonnes of coal in 2006-07.[4]Around 80 per cent of the domestic coal supplies in India are meant for coal based thermal power plants and coal transporta-tion forms 42 per cent of the total freight earnings of Indian railways. Mahagenco's Paras Thermal Power Station located near Akola completed 50 years in power generation on October 25 and marching towards overall renovation. Later, one more unit of 58MW was developed in the power station. Due to old age of the units, Mahagenco had replaced the old units with new ones and both of the units are non-exist-ent today.Paras TPS has started to witness a fresh life with commissioning of two new units in last couple of years. Currently, two units each with capacity of 250MW for a total of 500MW have been functioning at the power station, thus playing a vital role in state's power scenario. Besides, Mahagenco has proposed to develop one more new unit with capacity of 660MW.

What is Thermal power Plant

A thermal power station is a power plant in which heat en-ergy is converted to electric power. In most of the places in the world the turbine is steam-driven. Water is heated, turns into steam and spins a steam turbine which drives an elec-trical generator. After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated; this is known as a Rankine cycle. The greatest variation in the design of thermal power stations is due to the different heat sources, fossil fuel dominates here, although nuclear heat energy and solar heat energy are also used. Some prefer to use the term energy centre because such facilities convert forms of heat energy into electrical energy. Certain thermal power plants also are designed to produce heat energy for industrial purposes of district heating, or desalination of water, in addition to generating electrical power.

Types of Thermal Energy

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Almost all coal, nuclear, geothermal, solar thermal elec-tric, and waste incineration plants, as well as many natural gas power plants are thermal. Natural gas is frequently combus-ted in gas turbines as well as boilers. The waste heat from a gas turbine, in the form of hot exhaust gas, can be used to raise steam, by passing this gas through a Heat Recovery Steam Generator (HRSG) the steam is then used to drive a steam turbine in a combined cycle plant that improves overall efficiency. Power plants burning coal, fuel oil, or natural gas are often called fossil-fuel power plants. Some biomass-fueled thermal power plants have appeared also. Non-nuclear thermal power plants, particularly fossil-fueled plants, which do not use co-generation are sometimes referred to as conventional power plants.Commercial electric utility power stations are usually construc-ted on a large scale and designed for continuous operation. Vir-tually all Electric power plants use three-phase electrical gener-ators to produce alternating current (AC) electric power at a frequency of 50 Hz or 60 Hz. Large companies or institutions may have their own power plants to supply heating or electri-city to their facilities, especially if steam is created anyway for other purposes. Steam-driven power plants have been used to drive most ships in most of the 20th century until recently. Steam power plants are now only used in large nuc-lear naval ships. Shipboard power plants usually directly couple the turbine to the ship's propellers through gearboxes. Power plants in such ships also provide steam to smaller turbines driv-ing electric generators to supply electricity. Nuclear marine propulsion is, with few exceptions, used only in naval vessels. There have been many turbo-electric ships in which a steam-driven turbine drives an electric generator which powers an electric motor for propulsion.Combined heat and power plants (CH&P plants), often called co-generation plants, produce both electric power and heat for process heat or space heating. Steam and hot water.

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Diagram of a typical coal-fired thermal power station

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Thermal Power Plant

At present 54.09% or 93918.38 MW (Data Source CEA, as on 31/03/2011) of total electricity production in India is from Coal Based Thermal Power Station. A coal based thermal power plant converts the chemical energy of the coal into electrical energy. This is achieved by raising the steam in the boilers, ex-panding it through the turbine and coupling the turbines to the generators which converts mechanical energy into electrical energy.

Introductory overview

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In a coal based power plant coal is transported from coal mines to the power plant by railway in wagons or in a merry-go-round system. Coal is unloaded from the wagons to a moving underground conveyor belt. This coal from the mines is of no uniform size. So it is taken to the Crusher house and crushed to a size of 20mm. From the crusher house the coal is either stored in dead storage( generally 40 days coal supply) which serves as coal supply in case of coal supply bottleneck or to the live storage(8 hours coal supply) in the raw coal bunker in the boiler house. Raw coal from the raw coal bunker is supplied to the Coal Mills by a Raw Coal Feeder. The Coal Mills or pulveriser pulverizes the coal to 200 mesh size. The powdered coal from the coal mills is carried to the boiler in coal pipes by high pres-sure hot air. The pulverized coal air mixture is burnt in the boiler in the combustion zone.Generally in modern boilers tangential firing system is used i.e. the coal nozzles/ guns form tangent to a circle. The temperat-ure in fire ball is of the order of 1300 deg.C. The boiler is a wa-ter tube boiler hanging from the top. Water is converted to steam in the boiler and steam is separated from water in the boiler Drum. The saturated steam from the boiler drum is taken to the Low Temperature Superheater, Platen Superheater and Final Superheater respectively for superheating. The super-heated steam from the final super heater is taken to the High Pressure Steam Turbine (HPT). In the HPT the steam pressure is utilized to rotate the turbine and the resultant is rotational en-ergy. From the HPT the out coming steam is taken to the Re-heater in the boiler to increase its temperature as the steam becomes wet at the HPT outlet. After reheating this steam is taken to the Intermediate Pressure Turbine (IPT) and then to the Low Pressure Turbine (LPT). The outlet of the LPT is sent to the condenser for condensing back to water by a cooling water system. This condensed water is collected in the Hot well and is again sent to the boiler in a closed cycle. The rotational energy imparted to the turbine by high pressure steam is converted to electrical energy in the Generator.

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PrincipalCoal based thermal power plant works on the principal of Modi-fied Rankine Cycle.

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Components of Coal Fired Thermal Power Station:

Coal Preparation

Fig. Coal Handling Plant

i)Fuel preparation system: In coal-fired power stations, the raw feed coal from the coal storage area is first crushed into small  pieces and then conveyed to the coal feed hoppers at the boilers. The coal is next pulverized into a very fine powder, so that coal will undergo complete combustion during combustion process.                                   ** pulverizer is a mechanical device for the grinding of many different types of materials. For example,

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they are used to pulverize coal for combustion in the steam-generating furnaces of fossil fuel power plants Types of Pulver-isers: Ball and Tube mills; Ring and Ball mills; MPS; Ball mill; De-molition.  ii)Dryers:  they are used in order to remove the excess mois-ture from coal mainly wetted during transport. As the presence of moisture will result in fall in efficiency due to incomplete combustion and also result in CO emission

  iii)Magnetic separators: coal which is brought may contain iron particles. These iron particles may result in wear and tear. The iron particles may include bolts, nuts wire fish plates etc. so these are unwanted and so are removed with the help of magnetic separators.The coal we finally get after these above process are trans-ferred to the storage site.Purpose of fuel storage is two –

 Fuel storage is insurance from failure of normal operating supplies to arrive.

Storage permits some choice of the date of purchase, al-lowing the purchaser to take advantage of seasonal mar-ket conditions. Storage of coal is primarily a matter of pro-tection against the coal strikes, failure of the transporta-tion system & general coal shortages.

Fan

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In a boiler it is essential to supply a controlled amount of air to the furnace for Effective combustion of fuel and to evacuate hot gases formed in the furnace through the various heat transfer area of the boiler. This can be done by using a chimney or mechanical device such as fans which acts as pump.i) Natural fansWhen the required flow of air and flue gas through a boiler can be obtained by the stack (chimney) alone, the system is called natural draught. When the gas within the stack is hot, its spe-cific weight will be less than the cool air outside; therefore the unit pressure at the base of stack resulting from weight of the column of hot gas within the stack will be less than the column of extreme cool air. The difference in the pressure will cause a flow of gas through opening in base of stack. Also the chimney is form of nozzle, so the pressure at top is very small and gases flow from high pressure to low pressure at the top.

ii) Mechanized fansThere are 3 types of mechanized draught systems1)  Forced draught fans2)  Induced draught fans3)  Balanced draught fans

Forced draught fan: – In this system a fan called Forced draught fan is installed at the inlet of the boiler. This fan forces the atmospheric air through the boiler furnace and pushes out the hot gases from the furnace through superheater, reheater, economiser and air heater to stacks.

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Fig. FD FanInduced draught fan: – Here a fan called ID fan is provided at the outlet of boiler, that is, just before the chimney. This fan sucks hot gases from the furnace through the superheaters, economiser, reheater and discharges gas into the chimney. This results in the furnace pressure lower than atmosphere and affects the flow of air from outside to the furnace.

Fig. ID FanPrimary Draught fan:-In this system both FD fan and ID fan are provided. The FD fan is utilized to draw control quantity of air from atmosphere and force the same into furnace. The ID fan sucks the product of combustion from furnace and dis-charges into chimney. The point where draught is zero is called balancing point.

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Fig. PA Fan

There are two types of storage:

1. Live Storage (boiler room storage): storage from which coal may be withdrawn to supply combustion equip-ment with little or no remanding is live storage. This stor-age consists of about 24 to 30 hrs. of coal requirements of the plant and is usually a covered storage in the plant near the boiler furnace. The live storage can be provided with bunkers & coal bins. Bunkers are enough capacity to store the requisite of coal. From bunkers coal is transferred to the boiler grates.

2. Dead storage- stored for future use. Mainly it is for longer period of time, and it is also mandatory to keep a backup of fuel for specified amount of days depending on the

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reputation of the company and its connectivity. There are many forms of storage some of which are –

1. Stacking the coal in heaps over available open ground areas.

2. As in (I). But placed under cover or alternatively in bunkers.

3. Allocating special areas & surrounding these with high re-inforced concerted retaking walls.

Boiler and auxiliaries

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Fig. Boiler A Boiler or steam generator essentially is a container into which water can be fed and steam can be taken out at desired pressure, temperature and flow. This calls for application of heat on the container. For that the boiler should have a facility to burn a fuel and release the heat. The functions of a boiler thus can be stated as:-

1. To convert chemical energy of the fuel into heat energy2. To transfer this heat energy to water for evaporation as

well to steam for superheating.The basic components of Boiler are: -

1. Furnace and Burners2. Steam and Superheating

a. Low temperature super heaterb. Platen super heaterc. Final super heaterTypes Of Boiler.

Fire-tube Boilers

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Fig. Fire tube Boiler

In fire-tube boilers, combustion gases pass through the inside of the tubes with water surrounding the outside of the tubes. The advantages of a fire-tube boiler are its simple construction and less rigid water treatment requirements.The disadvantages are the excessive weight-per-pound of steam generated, excessive time required to raise steam pres-sure because of the relatively large volume of water, and inabil-ity to respond quickly to load changes, again, due to the large water volume.The most common fire-tube boilers used in facility heating ap-plications are often referred to as ''scotch'' or ''scotch marine'' boilers, as this boiler type was commonly used for marine ser-vice because of its compact size (fire-box integral with boiler section)

.Water tube Boiler

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Fig. Water tube Boiler in a water-tube boiler ('''Figure 3'''), the water is inside the tubes and combustion gases pass around the outside of the tubes. The advantages of a water-tube boiler are a lower unit weight-per-pound of steam generated, less time required to raise steam pressure, a greater flexibility for responding to load changes, and a greater ability to operate at high rates of steam generation.A water-tube design is the exact opposite of a fire-tube. Here, the water flows through the tubes and is encased in a furnace in which the burner fires. These tubes are connected to a steam drum and a mud drum. The water is heated and steam is pro-duced in the upper drum.

Economiser

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Fig. Economiser

It is located below the LPSH in the boiler and above pre heater. It is there to improve the efficiency of boiler by extract-ing heat from flue gases to heat water and send it to boiler drum.Advantages of Economiser include1) Fuel economy: – used to save fuel and increase overall effi-ciency of boiler plant.2) Reducing size of boiler: – as the feed water is preheated in the economiser and enter boiler tube at elevated temperature. The heat transfer area required for evaporation reduced consid-erably.

Air PreheaterThe heat carried out with the flue gases coming out of econom-iser are further utilized for preheating the air before supplying to the combustion chamber. It is a necessary equipment for supply of hot air for drying the coal in pulverized fuel systems to facilitate grinding and satisfactory combustion of fuel in the furnace

 Superheater

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Fig. Superheater Power plant furnaces may have a reheater section con-taining tubes heated by hot flue gases outside the tubes. Ex-haust steam from the high pressure turbine is rerouted to go in-side the reheater tubes to pickup more energy to go drive inter-mediate or lower pressure turbines. When a steam system is designed for superheat, the de-signer should ensure that the steam exit the superheater is su-perheated about 5.6oC (10oC) higher than the desired superheat temperature.  The steam temperature is not controlled using by-passes on the superheaters but by desuperheating equipment.

Types of Turbine

Steam turbines

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Fig. Steam Turbine

Steam turbines have been used predominantly as prime mover in all thermal power stations. The steam turbines are mainly di-vided into two groups: -

1. Impulse turbine2. Impulse-reaction turbine

The turbine generator consists of a series of steam turbines in-terconnected to each other and a generator on a common shaft. There is a high pressure turbine at one end, followed by an intermediate pressure turbine, two low pressure turbines, and the generator. The steam at high temperature (536 ‘c to 540 ‘c) and pressure (140 to 170 kg/cm2) is expanded in the turbine.

Water Turbine

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Fig. Water TurbineA water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. Water tur-bines are mostly found in dams to generate electric power from water kinetic energy.

Wind Turbine

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Fig. Wind Turbine

A wind turbine is a device that converts the wind's kinetic energy into electrical power. Wind turbines are manufactured in a wide range of vertical and hori-zontal axis types. The smallest turbines are used for ap-plications such as battery charging for auxiliary power for boats or caravans or to power traffic warning signs. Slightly larger turbines can be used for making contribu-tions to a domestic power supply while selling unused power back to the utility supplier via the electrical grid. Ar-rays of large turbines, known as wind farms, are becoming an increasingly important source of intermittent renew-able energy and are used by many countries as part of a strategy to reduce their reliance on fossil fuels.

Generator

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Fig. Generator Generator or Alternator is the electrical end of a turbo-generator set. It is generally known as the piece of equipment that converts the mechanical energy of turbine into electricity. The generation of electricity is based on the principle of electro-magnetic induction. In electricity generation, a generator is a device that converts mechanical energy to electrical energy for use in an external circuit. Sources of mechanical energy include steam turbines, gas turbines, water turbines, and internal combustion engines and even hand cranks. The first electromagnetic gener-ator, the Faraday disk, was built in 1831 by British scientist Mi-chael Faraday. Generators provide nearly all of the power for electric power grids.The reverse conversion of electrical energy into mechanical en-ergy is done by an electric motor, and motors and generators have many similarities. Many motors can be mechanically driven to generate electricity and frequently make acceptable manual generators.

Condenser

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Fig. Condenser The condenser condenses the steam from the exhaust of the turbine into liquid to allow it to be pumped. If the condenser can be made cooler, the pressure of the exhaust steam is re-duced and efficiency of the cycle increases. The functions of a condenser are:-1) To provide lowest economic heat rejection temperature for steam.2) To convert exhaust steam to water for reserve thus saving on feed water requirement.3)  To introduce make up water.We normally use surface condenser although there is one direct contact condenser as well. In direct contact type exhaust steam is mixed with directly with D.M cooling water.

Cooling tower

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Fig. Cooling Tower

The cooling tower is a semi-enclosed device for evaporative cooling of water by contact with air. The hot water coming out from the condenser is fed to the tower on the top and allowed to tickle in form of thin sheets or drops. The air flows from bottom of the tower or perpendicular to the direction of water flow and then exhausts to the atmosphere after effect-ive cooling.The cooling towers are of four types: -1. Natural Draft cooling tower2. Forced Draft cooling tower3. Induced Draft cooling tower4. Balanced Draft cooling tower

Boiler feed pump

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Fig. Boiler Feed pump

Boiler feed pump is a multi stage pump provided for pumping feed water to economiser. BFP is the biggest auxiliary equipment after Boiler and Turbine. It consumes about 4 to 5 % of total electricity generation. Boiler feed water pump is a specific type of pump used to pump feed water into a steam boiler. The water may be freshly supplied or returning condens-ate produced as a result of the condensation of the steam produced by the boiler. These pumps are normally high pressure units that take suction from a condensate return system and can be of the centrifugal pump type or posit-ive displacement type.

Ash handling system

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Fig. Ash Handling Plant The disposal of ash from a large capacity power station is of same importance as ash is produced in large quantities. Ash handling is a major problem.i) Manual handling: While barrows are used for this. The ash is collected directly through the ash outlet door from the boiler into the container from manually.ii) Mechanical handling: Mechanical equipment is used for ash disposal, mainly bucket elevator, belt conveyer. Ash gener-ated is 20% in the form of bottom ash and next 80% through flue gases, so called Fly ash and collected in ESP. iii) Electrostatic precipitator: From air preheater this flue gases (mixed with ash) goes to ESP. The precipitator has plate banks (A-F) which are insulated from each other between which the flue gases are made to pass. The dust particles are ionized and attracted by charged electrodes. The electrodes are main-tained at 60KV.Hammering is done to the plates so that fly ash comes down and collect at the bottom. The fly ash is dry form is used in cement manufacture.

Advantages of coal based thermal Power Plant

They can respond to rapidly changing loads without diffi-culty

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A portion of the steam generated can be used as a process steam in different industries

Steam engines and turbines can work under 25 % of over-load continuously

Fuel used is cheaper Cheaper in production cost in comparison with that of

diesel power stations

Disadvantages of coal based thermal Power Plant

Maintenance and operating costs are high Long time required for erection and putting into  action A large quantity of water is required Great difficulty experienced in coal handling Presence of troubles due to smoke and heat in the plant Unavailability of good quality coal Maximum of  heat  energy lost Problem of ash removing

Thermal Power Plants Operation Thermal power plants use water as working fluid. Nuclear and coal based power plants fall under this category. The way en-ergy from fuel gets transformed into electricity forms the work-ing of a power plant. In a thermal power plant a steam turbine is rotated with help of high pressure and high temperature steam and this rotation is transferred to a generator to produce electricity.

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Fig.1 Power is produced in thermal power plants by rotating steam turbine

Energy absorption from steamWhen turbine blades get rotated by high pressure high temper-ature steam, the steam loses its energy. This in turn will result in a low pressure and low temperature steam at the outlet of the turbine. Here steam is expanded till saturation point is reached. Since there is no heat addition or removal from the steam, ideally entropy of the steam remains same. This change is depicted in the following p-v and T-s diagrams. If we can bring this low pressure, low temperature steam back to its ori-ginal state, then we can produce electricity continuously.

Fig.2 Pressure and temperature drop of steam when turbine absorbs energy from it

Use of CondenserCompressing a fluid which is in gaseous state requires a huge amount of energy,so before compressing the fluid it should be converted into liquid state. A condenser is used for this pur-

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pose, which rejects heat to the surrounding and converts steam into liquid. Ideally there will not be any pressure change during this heat rejection process, since the fluid is free to expand in a condenser. Changes in fluid are shown in the p-v and T-s dia-gram below.

Fig.3 Use of condenser in order to transform vapor into liquid state

PumpAt exit of the condenser fluid is in liquid state, so we can use a pump to raise the pressure.During this process the volume and temperature (2-3 deg.C rise)of fluid hardly changes, since it is in liquid state. Now the fluid has regained its original pressure.

Fig.4 Compressor pumps the fluid to its original pressure

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Heat Addition in Boiler & Rankine CycleHere external heat is added to the fluid in order to bring fluid back to its original temperature. This heat is added through a heat exchanger called a boiler. Here the pressure of the fluid remains the same, since it is free to expand in heat exchanger tubes. Temperature rises and liquid gets transformed to vapor and regains its original temperature. This completes the ther-modynamic cycle of a thermal power plant, called Rankine Cycle. This cycle can be repeated and continuous power pro-duction is possible.

Fig.5 Heat addition at boiler brings the fluid to its original temperature

Condenser Heat Rejection - Cooling TowerIn order to reject heat from the condenser a colder liquid should make contact with it. In a thermal power plant continuous sup-ply of cold liquid is produced with the help of a cooling tower. Cold fluid from the cooling tower absorbs heat from a con-denser and gets heated, this heat is rejected to the atmosphere via natural convection with the help of a cooling tower.

Boiler furnace for Heat AdditionHeat is added to the boiler with help of a boiler furnace. Here fuel reacts with air and produces heat. In a thermal power plant, the fuel can be either coal or nuclear. When coal is used as a fuel it produces a lot of pollutants which have to be re-moved before ejecting to the surroundings. This is done using a series of steps, the most important of them is an electro static precipitator (ESP) which removes ash particles from the ex-

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haust. Now much cleaner exhaust is ejected into the atmo-sphere via a stack.

Fig.6 Main accessories of Rankine cycle - Cooling tower, Boiler furnace, ESP & Chimney

Optimizing a Thermal plant performanceThere are various flow parameters which have to be fine-tuned in order to get optimum performance from a thermal power plant.Lowering the condenser temperature or raising the aver-age boiler temperature will result in a high efficiency power plant cycle according to the 2nd law of thermodynamics (Carnot efficiency),most of the performance improving techno-logies are working on this idea. Some latest trends are listed below.

1. Expanding Turbine After SaturationExpanding the steam in the turbine even after reaching the saturation point may be a dangerous affair. As the steam goes below saturation, wetness of the steam increases. These condensed water droplets collide with the turbine blades rotating at a high speed, thus it can cause extreme tip erosion to the blades. Turbine blade tip erosion is shown in figure below. But as you expand more you will be able to absorb more energy from the steam, thus increasing power plant efficiency. Up to 15% wetness level is considered to be safe for steam turbine operation. So most of the steam tur-bine will expand up to this point in order to extract maximum energy from the fluid. This is shown in figure below.

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Fig.7 Expanding turbine below saturation point in order to gain maximum power from steam

2. Raising average boiler temperatureIf you can increase the average heat addition temperature of the boiler, that will result in a power plant with higher effi-ciency. One way to do this is to increase the compressor pressure. This will shift the saturation point of the fluid to a higher level, thus providing higher average temperature of heat addition. This is shown in the figure below. The blue line represents change in the cycle after raising the compressor pressure.

Fig.8 Raising compressor pressure in order achieve higher average boiler temperature

Conclusion

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Company has proposed to set-up 500 MW Coal fired Thermal Power Project based on Super Critical Techno-logy. State Government has supported this Project and has is-sued letter of support to provide all kind of administrative sup-port required. The Company has already acquired the land re-quired for the Main plant from Industrial Development Corpora-tion and has made the requisite payments. The remaining re-quired land has been identified and the process of acquisition is underway. The Project requires about 351,000 Tonnes coal based on aver-age Operational at 87.63 % PLF, generation at 462 MW Appro-priate arrangements are proposed to be done. The water is taken from two barrages Lower Mun barrage and upper Mun barrage near Balapur. The Project will require about 150 cubic meters per hour make-up water during operation. A raw water reservoir of 25200m3 capacity to hold 7 days requirement for plant requirement of water will be constructed at the plant site. Of the total 500 MW of power is proposed to be sold as 4.15 as per CERC tariff. Considering the cost of generation of Rs. 2.35 per unit, company does not envisage any difficulties in selling the power through merchant route. Power Evacuation will be through two double circuit 440 KV transmission lines connect-ing the Project to the MSEB substation and State MAHAGENCO substation.

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Agnihotri College of engineeringNagthana, wardha

The student of Agnihotri College of engineering, wardha had gone for an industrial visit to paras thermal power station, akola and had learned about the power generation. Such indus-trial visit help the student in understanding the practical applic-ation side of the course

DEPARTMENT OF ELeCTRICAL ENGINEERING 3 RD YEAR

Reference

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1."Diagram of a typical coal-fired thermal power sta-tion" (PDF). Retrieved 21 April 2013.

2. "Coal supply to various power stations" (PDF). Retrieved 21 April 2013.

3. "Indian Railways, CIL to collaborate for additional coal transport capacity". Mining weekly.com, 14 February 2013. Retrieved 21 April 2013.

http://www.learnengineering.org/2013/01/thermal-power-plant-work-ing.html

http://indianpowersector.com/home/power-station/thermal-power-plant/

http://www.electrical4u.com/thermal-power-generation-plant-or-ther-mal-power-station/

http://wikimapia.org/10530304/Paras-Thermal-Power-Station-MAHA-GENCO

OUR EXPERIENCE FROM THE INDUSTRIAL VISIT:

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After completing the industrial visit, we have upgraded our knowledge at a very great level. It was a good learning experi-ence. In each and every department, we got some or the other new ideas and new thinking which was necessary for develop-ment.

Thank You

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