Post on 14-Apr-2017
Training Report Of Koderma Thermal Power Station
SUMIT KUMAR B.tech , 7th Semester Reg no- 11202437 Civil Engineering Lovely Professional University
DAMODAR VALLEY CORPORATION BANJHEDIH , JHARKHAND
KODERMA THERMAL POWER STATION BANJHEDIH, JHARKHAND
INDUSTRIAL TRAINING 1 JUNE 2015 TO 30 JUNE 2015
Submitted by:Sumit kumarB.tech, 7th SemesterCivil engineeringReg no: 11202437Lovely Professional University
Submitted to: B.GOSWAMI (S.E. CIVIL) D.V.C, K.T.P.S, KODERMA
PREFACE
I have done my vocational training in KODERMA THERMAL POWER STATION (K.T.P.S) under DAMODAR VALLEY CORPORATION (D.V.C.) comprising 2 units of 500 MW each. It is a modern thermal power station having tilting burner corner fired combustion engineering USA design boiler and KWU West Germany Design Reaction Turbine. Both these main equipments have been designed, manufactured and supplied by Bharat Heavy Electricals Limited, India. MTPS units have many special features such as Turbo mill, DIPC (Direct Ignition of Pulverized Coal) system, HPLP bypass system, Automatic Turbine Run up system, and Furnace Safeguard Supervisory System.A student gets theoretical knowledge from classroom and gets practical knowledge from industrial training. When these two aspects of theoretical knowledge and practical experience together then a student is full equipped to secure his best. In conducting the project study in an industry, students get exposed and have knowledge of real situation in the work field and gains experience from them. The object of the summer training cum project is to provide an opportunity to experience the practical aspect of Technology in organization. It provides a chance to get the feel of the organization and its function. The fact that thermal energy is the major source of power generation itself shows the importance of thermal power generation in India – more than 60 percent of electric power is produced by steam plant in India.In steam power plants, the heat of combustion of fossil fuels is utilized by the boilers to raise steam at high pressure and temperature. The steam so produced is used in driving the steam turbine coupled to generators and thus in generating electrical energy Economic growth in India, being dependent on the power sector, has necessitated an enormous growth in electricity demand over the last two decades. Electricity in bulk quantities is produced in power plants.
ACKNOWLEDGEMENT
It is a matter of great pleasure and privilege for me to present this report of 30 days on the basis of practical knowledge gained by me during practical training at KODEMA THERMAL POWER STATION (K.T.P.S.), KODERMA (JHARKHAND) during session 1 june 2015 to 30 june 2015.I with full pleasure converge my heartiest thanks to Er. KESHAW KRISHNA & Er. K.N DUTTA to support me at each and every step of my training Schedule. I attribute hearties thanks to all Engineering departments and Engineers for their Ample Guidance during my training period. The dissertation has been prepared based on the vocational training undergone in a highly esteemed organization of Eastern region, a pioneer in Generation Transmission & Distribution of power, one of the most technically advanced & largest thermal power stations in JHARKHAND, the Koderma Thermal Power Station (K.T.P.S), under DVC. I would like to express my heartfelt gratitude to the authorities of KodermaThermal Power Station for providing me such an opportunity to undergo training in the thermal power plant of DVC, K.T.P.S. I would also like to thank the Engineers, highly experienced without whom such type of concept building in respect of thermal power plant would not have been possible.
INDEX
1. Introduction
Damodar valley corporation Necessity of the power plant Koderma thermal power station Summary and project highlights
2. Cooling tower Introduction of cooling tower Design of cooling tower Construction of cooling tower
3. Chimney Introduction of chimney Design of chimney Construction of chimney
4. Water treatment Introduction of water treatment Pre treatment plant DM plant treatment Waste water treatment
5. Coal handling plant Introduction of coal handling plant Design of coal handling plant Component of coal handling plant
INTRODUCTION
Electricity generation is the process of generating electric power from source of energy. In thermal power plant prime mover is steam driven. Water is heated, turns into steam and spins a steam turbine which drives an the process condenser and recycled to where it was heated; this is known as a Rankin cycle. The greatest variation in the design of thermal power stations is due to the different fossil fuel resources generally used to heat the water. Some prefer to use the term energy center 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. Globally, fossil fueled thermal power plants produce a large part of man-made CO2 emissions to the atmosphere, and efforts to reduce these are varied and widespread. Almost all coal, nuclear, geothermal, solar thermal electric, and waste incineration plants, as well as many natural gas power plants are thermal. Natural gas is frequently combusted in gas turbines as well as boilers. The waste heat from a gas turbine can be used to raise steam, 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 constructed on a large scale and designed for continuous operation. Electric power plants typically use three-phase electrical generators 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 electricity to their facilities, especially if steam is created anyway for other purposes. Steam-driven power plants have been used in various large ships, but are now usually used in large 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 driving electric generators to supply electricity. Shipboard steam power plants can be either fossil fuel or nuclear. Nuclear marine propulsion is, with few exceptions, used only in naval vessels. There have been perhaps about a dozen 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 lose energy when piped over substantial distance, so carrying heat energy by steam or hot water is often only worthwhile within a local area, such as a ship, industrial plant, or district heating of nearby buildings.
DAMODAR VALLEY CORPORATION
Damodar Valley Corporation was established on 7th July 1948.It is the most reputed company in the eastern zone of India. DVC in established on the Damodar River. The K.T.P.S under the DVC is the largest thermal plant in JHARKHAND. It has the capacity of 1000MW with 2 units of 500MW each. With the introduction of another two units of 500MW that is in construction it will be the largest in JHARKHAND. Koderma Thermal Power Station also known as K.T.P.S is located in the Koderma. It is one of the Thermal Power Stations of Damodar Valley Corporation . The total power plant campus area is surrounded by boundary walls and is basically divided into two major parts, first the Power Plant area itself and the second is the Colony area for the residence and other facilities for KTPS employees.s͛�
KODERMA THERMAL POWER STATION
This site is located at Banjhedih village in jainagar block of Koderma
District in Jharkhand state. The site is 5 km from River Barakar, on the
tailrace of Telaiya Dam. The nearest railway stations are Herodih and
koderma. Grand chord line of the Eastern Railways passes about 2km
from site.The water requirement of the thermal power plant including
expansion will be from River Barakar above telaiya. A closed cycle
circulating water system is proposed. Make up water requirement for
present stage of the plant is estimated at 4000m3/hr. DVC.
NECESSITY OF THE POWER PLANT
“Power to progress”
Energy provides the powers to progress. The natural resources of a
country may be turned into wealth if they are developed, used and
exchanged for other goods this cannot be achieved without energy.
Availability of sufficient energy and its proper use in any country can
result in this people using from substantial level to the highest standard
of living. It has been found that countries whose national output is
mainly agricultural and whose population lives mostly in rural
communities enjoy low per capita growth of energy consumption is
dependent is the extent to which industrial activity forms a part of its
energy usage a distinct changes. Once energy is made suitable in excess
of domestic needs it has been round that it is not used solely as a
consumer good but becomes factor of production.
A growing proportion of energy is being met all over the world the
electricity. This trend will further be stimulated because of increasing
availability of clean electricity. This applies especially to developing
countries because their industrial progress will be based on modern
technologies, which generally use electricity intensively.
COOLING TOWER
Introduction to cooling tower
A cooling tower is a heat rejection device which rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near the dry-bulb air temperature.
Common applications include cooling the circulating water used in oil refineries, petrochemical and other chemical plants, thermal power stations and HVAC systems for cooling buildings. The classification is based on the type of air induction into the tower: the main types of cooling towers are natural draft and induced draft cooling towers.
If that same plant had no cooling tower and used once-through cooling water, it would require about 100,000 cubic metres an hour and that amount of water would have to be continuously returned to the ocean, lake or river from which it was obtained and continuously re-
supplied to the plant. Furthermore, discharging large amounts of hot water may raise the temperature of the receiving river or lake to an unacceptable level for the local ecosystem. Elevated water temperatures can kill fish and other aquatic organisms (see thermal pollution), or can also cause an increase in undesirable organisms such as invasive species of Zebra mussels or algae. A cooling tower serves to dissipate the heat into the atmosphere instead and wind and air diffusion spreads the heat over a much larger area than hot water can distribute heat in a body of water. Some coal-fired and nuclear power plants located in coastal areas do make use of once-through ocean water. But even there, the offshore discharge water outlet requires very careful design to avoid environmental problems.
Cross section of cooling tower
The towers vary in size from small roof-top units to very large hyperboloid structures that can be up to 200 metres tall and 100 metres in diameter, or rectangular structure that can be over 40 metres tall and 80 metres long. Smaller towers are normally factory-built, while larger ones are constructed on site. They are often associated with nuclear
power plants in popular culture. Industrial cooling towers can be used to remove heat from various sources such as machinery or heated process material. The primary use of large, industrial cooling towers is to remove the heat absorbed in the circulating cooling water systems used in power plants, petroleum refineries, petrochemical plants, natural gas processing plants, food processing plants, semi-conductor plants, and other industrial facilities. The circulation rate of cooling water in a typical 700 MW coal-fired power plant with a cooling tower amounts to about 71,600 cubic metres an hour (315,000 U.S. gallons per minute) and the circulating water requires a supply water make-up rate of perhaps 5 percent (i.e., 3,600 cubic metres an hour).If that same plant had no cooling tower and used once-through cooling water, it would require about 100,000 cubic metres an hour [4] and that amount of water would have to be continuously returned to the ocean, lake or river from which it was obtained and continuously re-supplied to the plant. Furthermore, discharging large amounts of hot water may raise the temperature of the receiving river or lake to an unacceptable level for the local ecosystem. Elevated water temperatures can kill fish and other aquatic organisms. A cooling tower serves to dissipate the heat into the atmosphere instead and wind and air diffusion spreads the heat over a much larger area than hot water can distribute heat in a body of water. Some coal-fired and nuclear power plants located in coastalareas do make use of once-through ocean water. But even there, the offshore discharge water outlet requires very careful design to avoid environmental problems.Petroleum refineries also have very large cooling tower systems. A typical large refinery processing 40,000 metric tonnes of crude oil per day (300,000 barrels per day) circulates about 80,000 cubic metres of water per hour through its cooling tower system.The world's tallest cooling tower is the 200 metre tall cooling tower of Niederaussem Power Plant.
Design of cooling tower
Some commonly used terms in the cooling tower industry Drift - Water droplets that are carried out of the cooling tower with the exhaust air. Drift droplets have the same concentration of impurities as the water entering the tower. The drift rate is typically reduced by employing baffle-like devices, called drift eliminators, through which the air must travel after leaving the fill and spray zones of the tower.Blow-out - Water droplets blown out of the cooling tower by wind, generally at the air inlet openings. Water may also be lost, in the absence of wind, through splashing or misting. Devices such as wind screens, louvers, splash deflectors and water diverters are used to limit these losses.Plume - The stream of saturated exhaust air leaving the cooling tower. The plume is visible when water vapor it contains condenses in contact
with cooler ambient air, like the saturated air in one's breath fogs on a cold day. Under certain conditions, a cooling tower plume may present fogging or icing hazards to its surroundings. Note that the water evaporated in the cooling process is "pure" water, in contrast to the very small percentage of drift droplets or water blown out of the air inlets.Blow-down - The portion of the circulating water flow that is removed in order to maintain the amount of dissolved solids and other impurities at an acceptable level. It may be noted that higher TDS (total dissolved solids) concentration in solution results in greater potential cooling tower efficiency. However the higher the TDS concentration, the greater the risk of scale, biological growth and corrosion. Leaching - The loss of wood preservative chemicals by the washing action of the water flowing through a wood structure cooling tower.Noise - Sound energy emitted by a cooling tower and heard (recorded) at a given distance and direction. The sound is generated by the impact of falling water, by the movement of air by fans, the fan blades moving in the structure, and the motors, gearboxes or drive belts.Approach - The approach is the difference in temperature between the cooled-water temperature and the entering-air wet bulb temperature (twb). Since the cooling towers are based on the principles of evaporative cooling, the maximum cooling tower efficiency depends on the wet bulb temperature of the air. The wet-bulb temperature is a type of temperature measurement that reflects the physical properties of a system with a mixture of a gas and a vapor, usually air and water vaporRange - The range is the temperature difference between the water inlet and water exit.Fill - Inside the tower, fills are added to increase contact surface as well as contact time between air and water. Thus they provide better heat transfer. The efficiency of the tower also depends on them. There are two types of fills that may be used:Film type fill (causes water to spread into a thin film)Splash type fill (breaks up water and interrupts its vertical progress)
Costruction of cooling tower
Being very large structures, they are susceptible to wind damage, and several spectacular failures have occurred in the past. At Ferrybridge power station on 1 November 1965, the station was the site of a major structural failure, when three of the cooling towers collapsed due to vibrations in 85mph winds. Although the structures had been built to withstand higher wind speeds, the shape of the cooling towers meant that westerly winds were funnelled into the towers themselves, creating a vortex. Three out of the original eight cooling towers were destroyed and the remaining five were severely damaged. The towers were rebuilt and all eight cooling towers were strengthened to tolerate adverse weather conditions. Building codes were changed to include improved structural support, and wind tunnel tests introduced to check tower structures and configuration.
CHIMNEY
Introtuction of chimeny
A chimney is a structure which provides ventilation for hot flue gases or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney, effect. The space inside a chimney locomotives and ships. In the United States, the term smokestack (colloquially, stack) is also used when referring to locomotive chimneys or ship chimneys, and the term funnel can also be used.
The height of a chimney influences its ability to transfer flue gases to the external environment via stack effect. Additionally, the dispersion of pollutants at higher altitudes can reduce their impact on the immediate surroundings. In the case of chemically aggressive output, a sufficiently tall chimney can allow for partial or complete self-neutralization of airborne chemicals before they reach ground level.
Design of chimney
A flue liner is a secondary barrier in a chimney that protects the masonry from the acidic products of combustion, helps prevent flue gas from entering the house, and reduces the size of an over-sized flue. Newly built chimneys have been required by building codes to have a flue liner in many locations since the 1950s. Chimneys built without a liner can usually have a liner added, but the type of liner needs to match the type of appliance it is servicing. Flue liners may be clay tile, metal, concrete tiles, or poured in place concrete. A chimney pot is placed on top of the chimney to expand the length of the chimney inexpensively, and to improve the chimney's draft. A chimney with more than one pot on it indicates that there is more than one fireplace on different floors sharing the chimney. A chimney cowl is placed on top of the chimney to prevent birds and other animals from nesting in the chimney. They often feature a rain guard to prevent rain or snow from going down the chimney. A metal wire mesh is often used as a spark arrestor to minimize burning debris from rising out of the chimney and making it onto the roof. Although the masonry inside the chimney can absorb a large amount of moisture which later evaporates, rainwater can collect at the base of the chimney. Sometimes weep holes are placed at the bottom of the chimney to drain out collected water. A chimney cowl or wind directional cap is a helmet-shaped chimney cap that rotates to
align with the wind and prevent a back draft of smoke and wind back down the chimney. An H-style cap (cowl) is a chimney top constructed from chimney pipes shaped like the letter H. It is an age-old method of regulating draft in situations where prevailing winds or turbulences cause downdraft and back puffing. Although the H cap has a distinct advantage over most other downdraft caps, it fell out of favour because of its bulky design. It is found mostly in marine use but has been regaining popularity due to its energy-saving functionality. The H-cap stabilizes the draft rather than increasing it. Other downdraft caps are based on the Venture effect, solving downdraft problems by increasing the updraft constantly resulting in much higher fuel consumption.
A chimney damper is a metal plate that can be positioned to close off the chimney when not in use and prevent outside air from entering the interior space, and can be opened to permit hot gases to exhaust when a fire is burning. A top damper or cap damper is a metal spring door placed at the top of the chimney with a long metal chain that allows one to open and close the damper from the fireplace. A throat damper is a metal plate at the base of the chimney, just above the firebox, that can be opened and closed by a lever, gear, or chain to seal off the fireplace from the chimney. The advantage of a top damper is the tight weatherproof seal that it provides when closed, which prevents cold outside air from flowing down the chimney and into the living space — a feature that can rarely be matched by the metal-on-metal seal afforded by a throat damper. Additionally, because the throat damper is subjected to intense heat from the fire directly below, it is common for the metal to become warped over time, thus further degrading the ability of the throat damper to seal. However, the advantage of a throat damper is that it seals off the living space from the air mass in the chimney, which, especially for chimneys positioned on an outside of wall of the home, is generally very cold. It is possible in practice to use both a top damper and a throat damper to obtain the benefits of both. The two top damper designs currently on the market are the Lyemance (pivoting door) and the Lock Top (translating door).
In the late Middle Ages in Western Europe the design of crow-stepped gables arose to allow maintenance access to the chimney top, especially for tall structures such as castles and great manor houses.
Construction of chimney
As a result of the limited ability to handle transverse loads with brick, chimneys in houses were often built in a "stack", with a fireplace on each floor of the house sharing a single chimney, often with such a stack at the front and back of the house. Today's heating systems have made chimney placement less critical, and the use of non-structural gas vent pipe allows a flue gas conduit to be installed around obstructions and through walls. In fact, most modern high-efficiency heating appliances do not require a chimney. Such appliances are generally installed near an external wall, and a non combustible wall thimble allows a vent pipe run directly through the external wall. On a pitched roof where a chimney penetrates a roof, flashing is used to seal up the joints. The down-slope piece is called an apron, the sides receive step flashing and a cricket is used to divert water around the upper side of the chimney underneath the flashing Industrial chimneys are commonly referred to as flue gas stacks and are generally external structures, as opposed to those built into the wall of a building. They are generally located adjacent to a steam-generating boiler or industrial furnace and the gases are carried to them with ductwork. Today the use of reinforced concrete has almost entirely replaced brick as a structural component in the construction of industrial chimneys. Refractory bricks are often used as a lining, particularly if the type of fuel being burned generates flue gases containing acids. Modern industrial chimneys sometimes consist of a concrete windshield with a number of flues on the inside. The 300 metre chimney at Sasol Three consists of a 26 metre diameter windshield with four 4.6 metre diameter concrete flues which are lined with refractory bricks built on rings of corbels spaced at 10 metre intervals. The reinforced concrete can be cast by conventional formwork or sliding formwork. The height is to ensure the pollutants are dispersed over a wider area to meet legal or other safety requirements. A flue liner is a secondary barrier in a chimney that protects the masonry from the acidic products of combustion, helps prevent flue gas from entering the house, and reduces the size of an over-sized flue. Newly built chimneys have been required by building codes to have a flue liner in many locations since the 1950s. Chimneys built without a liner can usually have a liner added, but the type of liner needs to match the type of appliance it is servicing. Flue liners may be clay tile, metal, concrete tiles, or poured in place concrete.
Clay tile flue liners are very common in the United States. However, this is the only liner which does not meet Underwriters Laboratories 1777 approval and frequently have problems such as cracked tiles and improper installation. Clay tiles are usually about 3 feet (0.91 m) long, various sizes and shapes, and are installed in new construction as the chimney is built. A refractory cement is used between each tile. Metal liners may be stainless steel, aluminium, or galvanized iron and may be flexible or rigid pipes. Stainless steel is made in several types and thicknesses. Type 304 is used with firewood, wood pellet fuel, and non-condensing oil appliances, types 316 and 321 with coal, and type A1 29-4C is used with non-condensing gas appliances. Stainless steel liners must have a cap and be insulated if they service solid fuel appliances, but following the manufacturer's instructions carefully. Aluminium and galvanized steel chimneys are known as class A and class B chimneys. Class A are either an insulated, double wall stainless steel pipe or triple wall, air-insulated pipe often known by its generalized trade name Metalbestos. Class B are uninstalled double wall pipes often called B-vent, and are only used to vent non-condensing gas appliances. These may have an aluminium inside layer and galvanized steel outside layer. Condensing boilers do not need a chimney. Concrete flue liners are like clay liners but are made of a refractory cement and are more durable than the clay liners. Poured in place concrete liners are made by pouring special concrete into the existing chimney with a form. These liners are highly durable, work with any heating appliance, and can reinforce a weak chimney, but they are irreversible.
A characteristic problem of chimneys is they develop deposits of creosote on the walls of the structure when used with wood as a fuel. Deposits of this substance can interfere with the airflow and more importantly, they are combustible and can cause dangerous chimney fires if the deposits ignite in the chimney.
Heaters that burn natural gas drastically reduce the amount of creosote build-up due to natural gas burning much cleaner and more efficiently than traditional solid fuels. While in most cases there is no need to clean a gas chimney on an annual basis that does not mean that other parts of the chimney cannot fall into disrepair. Disconnected or loose chimney fittings caused by corrosion over time can pose serious dangers for residents due to leakage of carbon monoxide into the home
WATER TREATMENT PLANT
Introduction of water treatment plant
Besides treating the circulating cooling water in large industrial cooling tower systems to minimize scaling and fouling, the water should be filtered to remove particulates, and also be dosed with biocides and algaecides to prevent growths that could interfere with the continuous flow of the water. Under certain conditions, a bio film of micro-organisms such as bacteria, fungi and algae can grow very rapidly in the cooling water, and can reduce the heat transfer efficiency of the cooling tower. Bio film can be reduced or prevented by using chlorine or other chemicals. Another very important reason for using biocides in cooling towers is to prevent the growth of Legionella, including species that causelegionellosis or Legionnaires' disease, most notably L. pneumophila, or Mycobacterium avium. The various Legionella species are the cause of Legionnaires' disease in humans and transmission is via exposure to aerosols—the inhalation of mist droplets containing the bacteria. Common sources of Legionella include cooling towers used in open recalculating evaporative cooling water systems, domestic hot water systems, fountains, and similar disseminators that tap into a public water supply. Natural sources include freshwater ponds and creeks.
French researchers found that Legionella bacteria travelled up to 6 kilometres (3.7 mi) through the air from a large contaminated cooling tower at a petrochemical plant in Pas-de-Calais, France. That outbreak killed 21 of the 86 people who had a laboratory-confirmed infection.[20]
Drift (or wind age) is the term for water droplets of the process flow allowed to escape in the cooling tower discharge. Drift eliminators are used in order to hold drift rates typically to 0.001–0.005% of the circulating flow rate. A typical drift eliminator provides multiple directional changes of airflow to prevent the escape of water droplets. A well-designed and well-fitted drift eliminator can greatly reduce water loss and potential for Legionella or water treatment chemical exposure.
Many governmental agencies, cooling tower manufacturers and industrial trade organizations have developed design and maintenance guidelines for preventing or controlling the growth of Legionella in cooling towers. Below is a list of sources for such guidelines
Pre- treatment Plant
(2+1) 2000M3 /hr. capacity raw water pumps installed in intake pump
house located near Telaiya reservoir will supply water to site through
two 100% capacity pipelines through raw water station. 10 days
requirement of raw water will be-stored at site in a reservoir. Raw
water drawn from the reservoir through (1+1) 4000M3 pumps will be
clarified through PLC operated three 200m3 /hr capacity clarification
(one working for each unit with the third as a common standby.)
Alum/Sodium carbonate/lime/polyelectrolyte and chlorine will be
dosed in the pre-treatment plant to accelerate coagulation process. The
filtered water be stored in an adequately sized filtered water tank
(capacity 20,000cum) including 4000 cum dead storage for fire water
requirement. Sludge from the clarifiers and rapid gravity filters will be
taken into sludge sump. The sludge will be pumped to the gravity type
sludge thickness. Under flow from the thickness will be pumped to
centrifuge by centrifuge feed pumps. Concentrate from the centrifuges
and supernatant from the thickness will be taken back to the inlet of the
clarifiers Solid cakes from centrifuge will be collected in sludge dumpers
for ultimate disposal. Filtered water will be distributed to various areas
of the plant through dedicated pump sets as follows:-
Four three working + 1 common standby 100M3 /hr. filtered water
pump sets for supply water to the 3 DM plant streams, [2 streams
working and the third stream as standby] each streams having a
capacity of 90 M3/hr.
Three -75 M3/hr (2 working + 1 standby0 capacity potable water pump
sets will water to the needs of the colony and plant potable water.
Chlorine dosing is envisaged on the pump suction lines to ensure
compliance to GOI Public Health standards. Potable water needs for the
colony and the plant area will be met by the 300 M3 capacity RCC
overhead tank.
Bearing Cooling water system:
Demineralised water in a closed is envisaged for all auxiliary equipment
cooling of the power plant this will be re-cooled by filtered water,
circulating on the secondary side of the plate heat exchange (PHE).
Three –two operating plus one standby PHEs will be provided per unit.
A set of three (2 working with one standby) 3000 M3/hr capacity
auxiliary cooling water booster pumps will be used to establish
necessary pressure differential required for PHEs. These equipment will
be located suitably in the power plant building at ground ever for each
unit
Demineralized water to – make up to closed cycle BCW system will be
conditioned to avoid commission of carbon steel materials 3NOS (2+1)
of 2000 CMH ACW pump set utilizing demineraised water through PHEs
will distribute to various coolers of plant auxiliaries under uniform
pressure .
Makeup water to ACW system will be made available from the DM
water storage tank this will be achieved through three 5 CMH (one for
each unit with a common standby) located near the DM water storage
tank and a typing is taken for make up to both unit ACW tanks.
Demineralization plant:
Assuming an average 3% makeup for the heat cycle; 1.0% makeup for
auxiliary cooling system, and other uses such as makeup to hydrogen
generation plant, and considering regeneration time of 6 hours, a fully
automatic PLC based Dimineralizing plant having three- 100 cum/hr
capacity streams ( 2 normally operating) will be provided to have mixed
bed cutlet nullity as follows:
-Silica less than 0.01 ppm as Sio2 -pH
7.0+0.2-conductivity Less than 0.1 micronhos/cum At 25oC
The filtered water will be pumped to DM plant through activated carbon
filters, cation exchanges, degasifies, anion exchanges and mixed beds all
installed within the DM plant building. The Dm water will be stored in
two – 1500 cum capacity steel plate fabricated vertical cylindrical DM
water storage tanks along with proper breathers and floating PVC ball
arrangement to prevent absorption of atmospheric gases. The DM water
will be used for heat cycle makeup, auxiliary cooling circuit makeup and
Hydrogen generation plant Dm water from storage tanks will be
transported to the unit condensate storage tanks two numbers each of
500 cum capacity through three nos. 75 CMH capacity pimps. Two 100
per cent capacity boiler fill pump sets common for 2 units will be
installed at DM water storage tanks for initial fill for supplying Dm
water to heat make up as shown on the DM water system.
Chemical Feed System
Unit wise chemical feed system will be provided for feeding (i)
Trisodium phosphate in the boiler drum (high pressure feed system)
and (ii) Neutralizing amines such as ammonia morpholine and
cyclohexylmine in the condensate pump discharge/boiler feed suction
line (low pressure feed system) condensate tank outlet to maintain the
chemical concentration in the drum water and feed water within
permissible limits for trouble – free operation of the plant. The chemical
feed system plant will be located at ground level near each unit between
B/C bays.
Low pressure chemical dosing system of each unit will consist of:-
An adequately sized mixing tank provided with stirrer and a metering
tank.
Two (2) full capacity metering pump sets complete with suction filters,
valves, specialties, and other accessories with pipe work, fittings etc as
necessary Normally, one pump set will run intermittently while the
other pump set will be standby.
High pressure chemical dosing system of each unit will consist of. An
adequately sized mixing tank at a higher level provided with stirrer and
a metering tank for gravity drawl of chemical solution from mixing tank.
Two full capacity (one operating while the other standby) metering
pump sets complete with suction filters, valves, specialties and other
accessories with pipework is used for the each unit water drum.
Station Effluent Treatment System
Main plants drains consisting of waste water having light density fine
suspended particles from different areas as well as other effluents such
as boiler blow down, DM plant effluent (i.e.) Regeneration effluent from
DM plant will be neutralized in a neutralization pit before discharge to
setting sump. Bottom ash hopper over-flow, service water drains etc
will be led to adequately size underground waste water settling sumps
and the resulting water will be used for the CHP dust suppression
system.
Effluent from coal handling plant (CHP) primary consisting of coal dust
Aden water from various dust extraction points as well as dust
suppression system and run off water from coal-pile will be led to a
separate setting/guard pond located near the coal yard conveniently.
Effluents from oil unload will be taken to oil-water separate from where
the separated oil will taken for mixing with coal for burning in the boiler
and the water led to the CHP sump Skimming tank is provided
separately to remove contaminated oil etc.
The effluent water from ash pond & other station waste will be pumped
to the Guard pond: and will be treated to maintain acceptable standards
to Authorities and recycled back to Ash handling plant sump for each
disposal.
Condensate polishing system
The Condensate Polishing System will be designed to remove dissolved
and suspended solids corrosion products & other impurities from
condensate during startup, normal operation and periods or condenser
tube leakage to maintain the feed water and stream purity requirements
of the boiler and turbine. The condensate polisher will be located in
condensate feed water cycle between the condensate pump discharge
and the condenser condensate position system will consist of 3X33.3%
units i.e. each vessel having a capacity of 4 5 regeneration
arrangements.
Chemical Laboratory
A chemical laboratory will be provided for the day to resting of water
quality steam quality blow down etc. Compressed Air System
The control air requirement for the 2X500 MW plant will be met by
three-32 Nm3/min. Capacity 8.5 kg/cm2 (g) discharge pressure rotary,
screw type oil free compressors. The requirements of instruments air
for two units will be met by one (1) compressor on automatic mode
while second compressor wick be on load/unload mode and the third
compressors as standby. Each of the compressors will be of rotary
screw type, non-lubricated type complete with intercooler after cooler,
air receiver (dedicated to each compressor) three air drying plants, for
all the 3 compressors associated pipework, instrumentation, etc. the
silica del desiccant Providing dry air having a dew point of (-) 40oC at
atmospheric pressure will have 100% standby air drying adsorption
tower, etc to supply clean dry air to instrumentation and control system.
To meet the station service air requirements, four – b32 Nm3/min 8.5
kg/cm2 g discharge pressure rotary, men –lubricating type station air
compressor (same as that of instruments air compressors) will be
provided. While one compressor will be normally working for each unit
oil automatics that third compressor will be load/unload configuration
for the two units and fourth compressor will be standby for both the
unit. These compressors will have suitable interconnection with
instrument air header to improve the availability reliability of the
instrument air system with proper backflow protection i.e providing a
NRV with direction of flow towards instrument air side. Both the
instrument and service air supply networks will cover the entire
operating and maintenance area of both units of the power plant.
COAL HANDLING PLANTIntroduction of coal handling plant
It can be called the heart of thermal power plant because it provided the fuel for combustion in boiler. The coal is brought to the K.T.P.S through rails there are fourteen tracks in all for transportation of coal through rails. The main coal sources for K.T.P.S are SECL (South Eastern Coalfields Limited), NCL (Northern Coalfield Limited). Everyday 6 to 7 trains of coal are unloaded at K.T.P.S. Each train consists of 58 wagons and each wagons consists of 50 tones of coal. The approximate per day consumption at K.T.P.S is about 18000 metric tones. It costs approximate 4.5 crores of rupees per day including transportation expenses. The coal is firstly unloaded from wagon by wagon triplers then crushed by crushers and magnetic pulley and pulverized to be transformed to the boiler. The whole transportation of coal is through conveyor belt operated by 3-Ø Induction motor.The coal handling plant can broadly be divided into three sections :-1) Wagon Unloading System.2) Crushing System.3) Conveying System.
Design of coal handling plant
It unloads the coal from wagon to hopper. The hopper, which is made of Iron , is in the form of net so that coal pieces of only equal to and less than 200 mm. size pass through it. The bigger ones are broken by the workers with the help of hammers. From the hopper coal pieces fall on the vibrator. It is a mechanical system having two rollers each at its ends. The rollers roll with the help of a rope moving on pulley operatedby a slip ring induction motor with specification:
COAL HANDLING PLANT PROCEDURE
Generally most of the thermal power plants uses low grades bituminous coal. The conveyer belt system transports the coal from the coal storage area to the coal mill. Now the FHP(Fuel Handling Plant) department is responsible for converting the coal converting it into fine granular dust by grinding process. The coal from the coal bunkers. Coal is the principal energy source because of its large deposits and availability. Coal can be recovered from different mining techniques like• shallow seams by removing the over burnt expose the coal seam• underground mining.The coal handling plant is used to store, transport and distribute coal which comes from the mine. The coal is delivered either through a conveyor belt system or by rail or road transport. The bulk storage of coal at the power station is important for the continues supply of fuel. Usually the stockpiles are divided into three main categories.• live storage• emergency storage• long term compacted stockpile.The figure below shows the schematic representation of the coal handling plant. Firstly the coal gets deposited into the track hopper from the wagon and then via the paddle feeder it goes to the conveyer
belt#1A. Secondly via the transfer port the coal goes to another conveyer belt#2B and then to the crusher house. The coal after being crushed goes to the stacker via the conveyer belt#3 for being stacked or reclaimed and finally to the desired unit. ILMS is the inline magnetic separator where all the magnetic particles associated with coal get separated.Rated Output. : 71 KW.Rated Voltage. : 415 V.Rated Current. : 14.22 Amp.Rated Speed. : 975 rpm.No. of phases. : 3Frequency. : 50 Hz.The four rollers place themselves respectively behind the first andthe last pair of wheels of the wagon. When the motor operates the rollers roll in forward direction moving the wagon towards the “Wagon Table”. On the Wagon table a limit is specified in which wagon to be has kept otherwise the triple would not be achieved.
CRUSHING SYSTEM:-Crusher House:-It consists of crushers which are used to crush the coal to 20 mm. size. There are mainly two type of crushers working in KSTPS:-Primary Crushers i.e.i) Rail crushers ii) ii) Rotary breaker.Secondary Crushers. i.e. Ring granulators. Primary Crushers:-Primary crushers are provided in only CHP stage 3 system, whichbreaking of coal in CHO Stage 1 & Stage 2 system is done at wagon tripler hopper jail upto the size (-) 250 mm. Secondary Crusher:-Basically there are four ways to reduce material size : impact attrition , Shearing and Compression. Most of the crushers employ a combination of three crushing methods. Ring granulators crush by compressing accompanied by impact and shearing. The unique feature of this granulator is the minimum power required for tone for this type of material to be crushed compared to that of other type of crushers.
Construction of coal handling plant
Secondary crushers are ring type granulators crushing at the rate of 550 TPH/ 750 TPH for input size of 250 mm. and output size of 20 mm. The crusher is coupled with motor and gearbox by fluid coupling. Main parts of granulator like break plates, cages , crushing rings and other internal parts are made of tough manganese (Mn) steel. The rotor consists of four rows of crushing rings each set having 20 Nos. of toothed rings and 18 Nos. of plain rings. In CHP Stage 1 & 2 having 64 Nos. of ring hammers. These rows are hung on a pair of suspension shaft mounted on rotor discs. Crushers of this type employ the centrifugal force of swinging rings stroking the coal to produce the crushing action. The coal is admitted at the top and the rings stroke the coal downward. The coal discharges through grating at the bottom.
CONVEYING SYSTEM:-Stacker Reclaimer:-The stacker re-claimer unit can stack the material on to the pipe or reclaim the stack filed material and fed on to the main line conveyor. While stacking material is being fed from the main line conveyor via Tripler unit and vibrating feeder on the intermediate conveyor which feds the boom conveyor of the stacker cum reclaimer. During reclaimingthe material dis discharged on to the boom conveyor by the bucket fitted to the bucket wheel body and boom conveyor feeds the material on the main line conveyor running in the reverse direction.Conveyor belt Specification of Stacker / Reclaimer:-Belt width. : 1400 mm.Speed. : 2.2 m/second.Schedule of motor : All 3-Ø induction motors.Bucket wheel motor : 90 KW.Boom Conveyor motor : 70 KW.Intermediate Conveyor Motor : 90 KW.Boom Housing Motor : 22 KW.Slewing assembly. : 10 KW.Travel Motor : 7.5 KW.Vibrating Feeder. : 2x6 KW.Total installed power. : 360 KW.
ASH HANDLING PLANT
Introduction of ash handling plant
This plant can be divided into 3 sub plants as follows:-1) Fuel and Ash Plant.2) Air and Gas Plant.3) Ash Disposal and & Dust Collection Plant.Fuel and ash plant:-Coal is used as combustion material in KTPS, In order to get an efficient utilization of coal mills. The Pulverization also increases the overall efficiency and flexibility of boilers. However for light up and with stand static load , oil burners are also used. Ash produced as the result of combustion of coal is connected and removed by ash handling plant. Ash Handling Plant at KTPS consists of specially designed bottom ash and fly ash in electro static precipitator economizer and air pre-heaters hoppers. Air & Gas Plant:-
Air from atmosphere is supplied to combustion chamber of boiler through the action of forced draft fan. In KTPS there are two FD fans and three ID fans available for draft system per unit. The air before being supplied to the boiler passes through preheater where the flue gases heat it. The pre heating of primary air causes improved and intensified combustion of coal. The flue gases formed due to combustion of coal first passes round the boiler tubes and then it passes through the super heater and then through economizer . In re-heater the temperature of the steam (CRH) coming from the HP turbines heated with increasing the number of steps of re-heater the efficiency of cycle also increases. Ineconomizer the heat of flue gases raises the temperature of feed water. Finally the flue gases after passing through the Electro-Static Precipitator is exhausted through chimney.
Ash Disposal & Dust Collection Plant:-KSTPS has dry bottom furnace. Ash Handling Plant consists of especially designed bottom and fly ash system for two path boiler. The system for both units is identical and following description is applied to both the units the water compounded bottom ash hopper receives the bottom ash from the furnace from where it is stores and discharged through the clinker grinder. Two slurry pumps are provided which is common to both units & used to make slurry and further transportation to ash dyke through pipe line. Dry free fly ash is collected in two number of 31 fly ash hoppers which are handled by two independent fly ash system. The ash is removed from fly ash hoppers in dry state is carried to the collecting equipment where it is mixed with water and resulting slurry sump is dischargedUtilisation:-Utilisation of coal-ash is always practise than its disposal. There are various methods of utilisation of coal-ash along with established engineering technologies some of them are mentioned below:1. Manufacturing of building materials.2. Making of concrete.3. Manufacturing of pozzuolana cement.4. Road construction etc.
HOW MUCH THIS TRAINING WAS HELPFUL TO ME
The Training at the K.T.P.P. was very much helpful to me.
Before the training at this premier plant. I just had the theoretical
knowledge of various equipment, devices and machine. But after coming
here and getting supervisory hand and guidance of various senior
engineers, technicians and worker, we have full knowledge of what the
electricity really stands for the equipments and apparatus available
here were beyond imagination until one can see it practically, which
was the main purpose of having the training. We have through much
more and strong knowledge of mechanical and electrical field. On some
apparatus we had the opportunity to work under guidance and that was
really a big advantage for us.
Last but not the least the co-ordination provided by the technical staff
was very appreciable.