CHHATTISGARH STATE POWER GENERATION COMPANY LIMITED

CHHATTISGARH STATE POWER GENERATION COMPANY LIMITED

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A D e v e l o p m e n t S e r v i c e f o r I n d u s t r i e s & U t i l i t i e s

Certificate No.07/170/J

PROJECT HIGHLIGHTS

1. Agency : Chhattisgarh State Power Generation Company Limited

2. Project

: Banji – Bundali Thermal Power Project in village Bundali, distt. Korea, Chhattisgarh

3. Plant Capacity : 2x250 MW

5. Plant Configuration : Two units of 250 MW each

6. Location : Latitude 23º 06’ 35’’ N Longitude 82º 16’ 11’’ N

: a) Distance from Manendragarh town : 16 km

b) Distance from Highway (NH - 78) : 16 km

7. Nearest Railway Station &

Distance : Paradol Railway Station on

Anuppur – Chirmiri branch line of South Eastern railway : 11 km

8. Nearest Airport :

Raipur : 310 km

9. Nearest Port : Mumbai port : 700 km 10 Land Requirement A. Area within power plant boundary Acres

i. Main plant equipment &

water facilities 133.50

ii. Raw water reservoir 6.50 iii. Coal handling plant,

MGR & Railway facilities 159.00

iv. Green belt 100.00

B. Area outside power plant

i. Ash dyke area 125.00 ii. Township 100.00 iii. Corridor for water pipeline 6.00 iv. Corridor for rail line 80.00 Total 710.00


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11. Source of Water : Hasdeo River.

12. Water Requirement : 1855 Cu.m/hr.

13. Cooling System : Closed cycle cooling system with Natural Draft Cooling Towers

14. Primary Fuel & Source : SECL coal fields.

15. Support Fuel & Source : HFO/LDO from nearest refinery/oil depots

16. Fuel Requirement:

i. Primary fuel/coal : 2.68 mtpa With GCV of coal as 3400 kcal/kg, Station Heat Rate 2450 kcal/kwh and 85% PLF.

ii. Support fuel (LDO/ HFO)

:

4380 KL per year

17. Transportation

i. Coal By Railway System

ii. Support fuel By Railway System/road

18. Station Operation Philosophy

: Base Load

19. Chimney : One twin flue chimney of 220 meter high

20. Power Evacuation plan

: Through 220 KV transmission system

21. Project Commissioning Schedule

: Unit 1 - 33 months Unit 2 - 37 months

22. Life of the Plant : 25 years

23. Estimated Project Cost :

` 2934.76 Crores

24. Cost Per MW : ` 5.87 Crores

25. Levellised tariff at 85% PLF : ` 3.16/kwh


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1.0 INTRODUCTION & EXECUTIVE SUMMARY 1.1 The State of Chhattisgarh is endowed with abundant mineral wealth and

is in the threshold of developing industrial infrastructure to cater to the

enhanced need of the region. With industrial development receiving

highest priority, this nascent state has taken up several infrastructural

developments. With the urbanization and increased use of power for

irrigation, has created a level of demand, which has outstripped the

growth of power generation in the state. Several projects have been

identified from time to time meeting the growing demand of power. This

is one of identified projects.

1.2 Installed capacity of Chhattisgarh system at the end of 10th plan was

6839.7 MW including own generation, share from various central sector

projects. As per the 17th EPS, peak load of Chhattisgarh system peak

load at the end of 12th plan will be 5375 MW and 7279 MW by end of

year 2016-17. Considering the utilization factors of 70% Chhattisgarh

system requires about 7628 MW & 10398 MW by the year 2021-22 by

the year 2016-17. In order to bridge the gap between power demand

and supply generating projects will have to be planned & executed.

Keeping in view the growth rate of power demand in the State of

Chhattisgarh. Justification of the project is discussed in Chapter - 2.

1.3 As per the Electricity Act 2003, any generating company may establish,

operate & maintain power generating station.

1.4 Chhattisgarh State Power Generation Company Limited (CSPGCL) is

the electricity generation company and is logically in the right direction

to install the proposed project. Chhattisgarh State Electricity Board was

formed as per the Notification of the Government of Chhattisgarh dated


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15th November 2000, became functional w.e.f. 01.12.2000.

Chhattisgarh State Electricity Board has been further reorganized into

five companies in accordance with the provision contained in the

Section 131-134 of Electricity Act 2003 by the Govt. of Chhattisgarh.

Thus Chhattisgarh State Power Generation Company Limited

(CSPGCL) became functional w.e.f. 01.01.2009. CSPGCL being State

utility is logically in the right direction to install the proposed project.

1.5 M/s CSPGCL has engaged Desein Private Limited, Consulting

Engineers, for the preparation of Detailed Project Report of the

proposed 2x250 MW coal fired Thermal Power Project. The Detailed

Project Report besides bringing out broad equipment parameters

process flow inputs, present cost estimates and financial analysis in

line with Central Electricity Authority (CEA) guidelines, Central

Electricity Regulatory Commission (CERC) norms & SERC.

1.6 The proposed 2x250 MW power project site at Bundali village, block-

Manendragarh Korea District, Chhattisgarh. Nearest railway station is

Paradol at a distance of about 11 km.

1.7 The power plant will require about 1855 cu.m/hr. of raw water and 2.68

million tonnes of coal per annum at plant load factor of 85%.

1.8 Selection of unit rating & type of boiler unit has been discussed in

Chapter-4.0 and it is proposed to have two units each unit of 250 MW

capacity with conventional pulverized coal fired boiler.

1.9 Technical features outlining the salient parameters of the main plant and

equipment are discussed in the Chapter-5.0. The state-of-the-art

technology will be deployed for auxiliaries and sub-systems to ensure


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safe and continuous operation of the units with minimum unscheduled

outages.

1.10 Coal receipt will be through Indian Railway System. Unloading will be

through track hoppers of coal handling plant of the power station. Coal

handling system has the capacity of 1000 tph for two-shift operation.

Two stage crushing; stacking, reclaiming & feeding system have been

envisaged with provision of inter-connection with existing coal handling

system.

1.11 Fly ash generated is proposed to be handled in dry form. Bottom ash

will be extracted and disposed off by slurry disposal system. Ash

utilization will be as per MOEF guidelines. It is proposed to use ash for

the manufacture of cement, bricks & building material etc. Excess fly

ash will be disposed off in high concentration slurry form to ash dyke

1.12 Water will be drawn from Hasdeo River. The clarification and

demineralisation of plant water has been envisaged. Circulating water

system will be closed circuit cooling system using cooling towers. Make

up of water will be drawn from Hasdeo River. Clarified water will be

used for cooling tower makeup. Natural draft cooling towers are

proposed in view of low O&M Cost.

1.13 The electrical system proposed will be equipped with adequately sized

equipments and with generous redundancy to ensure uninterrupted

operation. Electrical equipment and systems are discussed in Chapter

6.2 of the report. Power will be evacuated through 220 KV transmission

lines.


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1.15 The proposed station envisages the state-of-the-art Distributed Digital

Control & Management Information System (DDCMIS) which will

integrate various closed loop sub-systems, open loop sub-systems,

monitoring and information sub-system covering the entire plant. The

system will also integrate the various proprietary control packages

supplied by the main equipment vendors for harmonious plant operation.

In Chapter – 6.3 of the report, instrumentation and control philosophy of

the proposed station is dealt in adequate detail.

1.16 Civil engineering aspects envisaged are given in the Chapter – 6.4

would be necessary to provide the staff colony for accommodating the

staff required for the O&M activities of the power plant.

1.17 To minimize emission of Suspended Particulate Matter (SPM) along with

boiler flue gases, Electrostatic Precipitators of high efficiency adequate

size will be provided at exit end of each boiler to bring down SPM

emission level under 50mg/Nm3. One twin-flue 220 m high stack will be

provided for the proposed units. Waste Water from the plant will be

properly treated before re-use and/or disposal. Discussion on the entire

environmental aspects has been detailed out in Chapter-8.0.

1.18 Adequate facilities will be developed for execution of the project based

on EPC package for BTG alongwith C&I and Civil works implementation

through the supplier selected for the purpose on Turnkey basis. All

remaining balance of plant equipment will be implemented through

agencies deployed in the field through open tender/limited enquiry. In

Chapter–9.0 of the report, O&M staff requirement for operation and

maintenance has been detailed out. This may under go revision as per

CSPGCL own norms of manpower requirement. The training

requirement of O&M persons is also discussed in this Chapter.


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1.19 The schedule of commissioning is 33 months for Unit-I and 37 months

for Unit-II from the investment approval.

1.20 It is proposed to finance the project such that Capital structure is built up

of Equity Capital 20% & Loan Capital 80%. The equity capital will be

built up by CSPGCL. Project cost with interest during construction is

estimated as ` 2934.76 Crores i.e. ` 5.87 Crores/MW. Levelised tariff at

85% PLF is estimated as ` 3.16/kwh.


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2.0 NEED FOR THE PROJECT

2.1 Power Scenario in Chhattisgarh

“Power Sector Report ” as per CEA website of Chhattisgarh State,

the installed capacity and share of power available from Central

Sector and Private Power Companies as on 31.3.2011is given in

Table–2.1. Likely capacity addition during 11th Plan including best

efforts project for Chhattisgarh system is given in Table 2.2.

TABLE – 2.1 (Figures in MW)

Thermal

Sector Hydro

Coal Gas Diesel Total

Nuclear Wind/ NES. Total

State 120.00 2060.00 0.00 0.00 2060.00 0.0 19.05 2199.05

Private 0.00 1600.00 0.00 0.00 1600.00 0.0 231.90 1831.00

Central Sector Share

0.00 804.00 00.00 0.00 804.00 47.52 0.00 851.82

Total 120.00 4464.00 00.00 0.00 4464.00 47.52 250.95 4882.47


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TABLE – 2.2

LIKELY CAPACITY ADDITION DURING 11TH PLAN INCLUDING BEST EFFORT PROJECTS FOR THE STATE: - CHATTISGARH

Project Name

Typ

e

Sta

tus

Installed Capacity (MW)

Capacity Addition

During XIth Plan (MW)

Benefits Shares of state (MW)

Commissioned /Slipped during

2007-2012 (MW)

Unit wise Commissioning

Date/ (Likely Date of

Commissioning)

CENTRAL-SECTOR

SIPAT STPS II U-4,5 T C 1000.00 1000.00 158 COMM 1000.00 27.05.2008

1.08.2008

BHILAI JV U-1,2 T C 500.00 500.00 50 COMM 500.00 20.04.2008

12.07.2009

*KORBA ST.-III U-7 T C 500.00 500.00 81 COMM 500.00 26.12.2010

KAHALGAON 6,7 T C 1000.00 1000.00 20 COMM 1000.00 16.03.2008

31.07.2009

CENTRAL – SECTOR TOTAL 309.00

STATE-SECTOR

KORBA EAST EXTN. U-2 T C 250.00 250.00 250.00 COMM 250.00 11.12.2007

STATE - SECTOR TOTAL 250.00

PRIVATE SECTOR

LANCO (AMARKANTAK)

U-1,2

T U 600.00 600.00 600 COMM 600.00 04.06.2009, 25.03.2010

RAIGARH TPP-(JINDAL) PH I & II U-1,2,3,4

T C 1000.00 1000.00 1000 COMM 1000.00 2.09.2007 10.02.2008 6.03.2008 17.06.2008

PRIVATE-SECTOR TOTAL:- 1600

WITH BEST EFFORTS

VINDHYACHAL IV U-2 T U 1000.00 500.00 31.27 (2011-2012)

SIPATI T U 1980.00 1980.00 313 (2010-2011)

MAUDA TPP U - 1 T U 1000.00 500.00 31.27 (2011-2012)

PRIVATE-SECTOR TOTAL:- 375.54

GRAND-TOTAL 2534.54

NOTE: U - UNDER CONSTRUCTION PROJECTS

C - COMMISSIONED * SHARES FROM CENTRAL SECTOR PROJECTS FOR WHICH M.O.P. ORDERS

ARE YET TO BE ISSUED ARE TENTATIVE


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From the Table 2.1 it will be seen that Chhattisgarh State has

installed capacity of 4882.47 MW including Central Sector Share.

With likely capacity addition (as per Table 2.2) the capacity

availability will be about 5258.01 MW (i.e. 4882.47+375.54) by the

year 2011-12 i.e. by end of 11th plan period.

Actual power supply position of Chhattisgarh system at the end of 10 th

Plan end, for the year 2010-11 and likely power supply position at the

end of 11th Plan are given in Table 2.3.

TABLE 2.3

Peak

Demand Peak Met

Peak Deficit/ Surplus

Peak Deficit/ Surplus

Energy require-

ment

Energy Availa- bility

Energy Deficit/ Surplus

Energy Deficit/ Surplus

(MW) (MW) (MW) (%) (MU) (MU) (MU) (%)

10th Plan end 2631 1907 -724 -27.5 14063 13169 -894 -6.4

2010-11 3148 2838 -310 -9.8 9250 110174

-175 -1.7

Likely supply position by end of 11th Plan

3565 3501 -64 -1.8 21785 27470 5685 26.2

From the above table, it may be also seen the State of Chhattisgarh

suffered peaking power deficit of 8.8% and energy deficit of (-) 1.7%

during year 2010-11.

As per the likely power supply position by end of 11th plan,

Chhattisgarh System will have energy surplus of 26.2%. The peak

deficit will be 1.8%. The above scenario will be only in the event of

commissioning of the identified best efforts projects and availability of

share from those projects


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The long term forecast of electrical energy requirements and that of

peak electric load demand for the years 2011-12, 2016-17 & 2021 -

2022 as given in the 17th Electric Power Survey of India for

Chhattisgarh System is given below:-

Period Energy Requirement

(Gwh)

Peak Load (MW)

2011-12 21785 3565

2016-17 33076 5375

2021-22 45116 7279

Considering utilization factors of 70%, Chhattisgarh system requires

installed capacity of 7678 MW by year 2016-17 and 10398 MW by

the year 2021-22. Thus to meet growing power requirement, power

projects are to be planned and implemented.

Considering the above scenario, the need for installing 2x250 MW TPP

is fully justified.

2.2 Government Policy for Power Generation/Requirements of Input/ Clearance

2.2.1 In the State of Chhattisgarh the Electricity Act 2003 has come in force.

As per Electricity Act 2003, clause 7 “Any Generating Company may

establish, operate and maintain a generating station without obtaining

licence under this act if it complies with technical standards relating to

connectivity with the grid.

CSPGCL being generating company is logically in the right direction to

install the proposed project.


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2.2.2 Requirement of input/clearances

2.2.2.1 Electricity Act 2003 do not indicate special requirement like clearances

from the concerned statutory or non-statutory authorities for setting up

thermal power plant. However clause 10 (3) stipulates that generating

company will:-

a. Submit technical details regarding its generating station to

appropriate commission (i.e. CERC/SERC) and the Authority

(i.e. CEA).

b. Co-ordinate with central transmission utility or state transmission

utility as the case may be for transmission of electricity

generated by it.

2.2.2.2 As per GOI guidelines for setting up of power project, various Inputs/Statutory/Non statutory inputs are to be tied-up.

Relevant requirements & status thereof are as follows:-

Sr. No.

Requirements Status

1. Approval of Competent Authority

Approval of competent authority will be obtained at appropriate stage

3. Land availability

Land has been identified. CSPGCL will take necessary steps for acquisition of land

4. Water Availability Water requirement is estimated as 1855 cu.m/hr.

The source of water is identified as Hasdeo River.

Water Resource Department, Govt. of Chhattisgarh will be approached by CSPGCL for


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Sr. No.

Requirements Status

allocation of water

5. Coal Availability Coal requirement is estimated as 2.68 million tonnes per annum.

Ministry of Coal / SLC (Long Term) will be approached by CSPGCL for allocation of coal.

6. Environment Clearance The project falls in Category “B” of the Ministry of Environment & Forest notification dated 14th September, 2006 and as such the State Environment Impact Assessment Authority will be approached for Terms of Reference (TOR) for EIA studies.

EIA studies will be conducted and the report will be submitted for obtaining Environmental clearance.

7. Airport Authority Clearance for Chimney Height

Airport Authority will be approached for their NOC forinstalling stack upto 220 meter height.

8. Power Absorption & Evacuation Plan

The power will be evacuated on 220 KV voltage level transmission system for the absorption in the State.

Chhattisgarh Power Transmission Corporation Limited will be taking necessary steps for evacuation of power as per the power evacuation scheme planned by them.

9. Approval by State Regulatory Commission/ Central Regulatory Commission

Approval of Chhattisgarh for sale of energy within the State and CERC for sale of electricity (if any) to other states will have to be obtained at appropriate stage.


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3.0 BASIC REQUIREMENTS

3.1 Infrastructure Requirements

A power station requires a number of basic inputs such as land, fuel,

water etc. Sitting of power station is primarily governed by the following

basic considerations:

a) Availability of land

b) Rail/road accessibility

c) Availability of fuel and proximity to source

d) Availability of water and proximity to source

e) Load demand / Power absorption plan

f) Environmental consideration

The most important criteria for selection of site for TPS is availability of

land with least R&R issues, fuel availability and its transportation, water

availability and acceptability from environmental considerations.

3.2 Site Selection

The basic requirement for establishing the project was studied in the

backdrop of available infrastructure facilities and requirement of

developing facilities to ensure compatibility and adequacy of system.

Various sites in Korea District were explored and three (3) potential

sites for the project were identified.

Site – 1 Bundali

Site – 2 Banji

Site – 3 SajaPahar

The site – 1, i.e. Bundali has been selected in view of adequate land

availability, proximity to water source, least R&R issue etc.


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3.3 Site Features

The selected site at Bundali village, Korea District, Chhattisgarh.

Nearest Railway station is Paradol at a distance of about 11 km.

Raipur Airport is 310 km away. The grid co-ordinates of the

proposed power plant are at Longitude 23º 06’ 35’’ N and Latitude 82º

16’ 11’’ N. Location map is given in Annexure 3.0

a) Land

Breakup of land required for the proposed units is as follows:-

Land Requirement


A. Area within power plant boundary Acres i. Main plant equipment &

water facilities 133.50

ii. Raw water reservoir 6.50 iii. Coal handling plant, MGR & Railway

facilities 159.00

iv Green belt 100.00 B. Area outside power plant i. Ash dyke area 125.00 ii. Township 100.00 iii. Corridor for water pipeline 6.0 iv. Corridor for rail line 80.00 Total 710.00

b) Rail/Road Accessibility

The nearest town Manendragarh is about 16 km from site. The

site is also well connected by road NH-78. Road network is

available for approach to site. Paradol Railway Station on

Annupur-Chirmiri broad gage of SER of about 11 km Railway

link from Paradol Railway siding to site will be made for the


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transportation of coal and fuel oil for the power plant. The rail

system will be developed as per recommendation of the study

conducted for the purpose. No problem is envisaged in

accessibility and transportation of heavy equipment to site by

road or rail.

c) Fuel & its Availability & Transportation

. Coal

Requirement of coal for the proposed TPP has been estimated

as 2.68. Million tones per annum. Major coal fields available

near the proposed project are at Sohagpur & also Bishrampur.

As per the “study & action plan to promote & develop

Chhattisgarh as the power hub of the Country” by PFC, the coal

reserves in Sohagpur Coal fields is approx 105 million tonnes

under Chhattisgarh & around 3760 million tones under MP. Coal

reserve in Bishrampur coal fields is approx 1450 million tonnes.

Hence, availability of coal will be either from Sohagpur coal

fields or from Bishrampur coal fields However, coal linkage or

allocation of captive coal mines will be for the propose project

will be as per MOC/SLC . CSPGCL will approach MOC/ SLC

for allocating coal for the proposed TPS.

Coal will be transported by Railway system

Fuel oil

Support fuel will be transported by road tankers or by Indian

Railway system. Start-up fuel will be Light Diesel Oil (LDO) and

support fuel will be HFO.


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d) Availability of Water

Requirement of make-up water for the proposed TPS has been

estimated as 1855 cum/hr.

Hasdeo River has been identified as source of water. The river

is flowing on South-West direction of the proposed site at a

distance of about 01 km. Take-up point may be constructed

river. However a weir will be required to be constructed across

the river at a suitable location to meet the water requirement for

the proposed power project. This, will be taken up at appropriate

time by CSPGCL with Water Resource Department, Govt. of

Chhattisgarh

e) Power evacuation

The generated power from the power plant switchyard will be

evacuated at 220 KV voltage level to Bishrampur S/S through

220 KV transmission lines. For absorption in the state.

Chhattisgarh State Power Transmission Company (CSPTCL)

will be implementing the power evacuation scheme as per the

plan envisaged by them.

f) Environmental Aspects

The Power Plant will be developed based on the guidelines of

the State Environmental Authorities. Suitable provisions will be

incorporated in the design of buildings, structures, and selection

of equipment so that there are no adverse effects due to

emissions, noise, and contamination of soil, water and air. A


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twin flue stack of 220 meters height will be provided for the

generating units as per the guidelines.

M/s CSPGCL will obtain TOR for conducting the EIA studies and

the recommendations and environmental stipulation will be

followed during the implementation phase of the project.


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4.0 UNIT RATING AND TYPE OF BOILER FOR THE PROJECT

4.1 Unit Rating

The plant is proposed to be established on the basis of unitized system.

The 500 MW capacity can be built up by:-

i. 2 units of 250 MW

ii. 1 unit of 500 MW

The plant is proposed to be built, based upon selection of configuration

to achieve:-

i) Economy of scale to achieve least per MW installed cost.

ii) Better efficiency of large sized boiler and steam turbine and lower

overall heat rate.

iii) Lower land requirement.

iv) Economical O&M cost aspects v) Lower staff requirement and accordingly colony size.

vi) Higher net saleable power on account of higher efficiency and

lower auxiliary power consumption.

To achieve better efficiency of the plant and more competitive tariff a

higher size unit of 500 MW can be adopted However the outage of unit

will result in total loss of the plant capacity. A configuration of 2x250

MW will be advantageous as at least 50% of generation is available

with the outage of one unit. The plant capacity with two generating


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units also gives flexibility in operation by adjusting load as per supply &

load demand.

Thus a unit size of 250 MW would be optimum considering relevant

aspects. 250 MW units are already in operation at a number of

stations in the country and adequate expertise in operation and

maintenance are locally available.

4.2 Boiler Technology for the Plant

On a general comparison of pulverized fuel boiler and CFBC boiler it

emerges that fluidized bed boiler are about 1% less efficient and cost is

higher than conventional pulverized fuel boiler. Unburnt carbon loss is

1 to 1.5% less in PF boiler and auxiliary consumption is also 9% as

compared to 11% in CFBC boiler. In case of the project at Banji-

Bundali domestic coal contains about 0.5% sulphur, therefore the SO2

emission will be well within the limits. Keeping in view of

characteristics of coal and project cost economy, pulverized fuel

technology is preferred than CFBC technology for boilers of the

proposed unit 2x250 MW Bundali TPP.


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5.0 TECHNICAL FEATURES OF THE BOILER & TG PLANT

5.1 Design Philosophy

The basic plant designs consider the proven concept as far as possible.

Judicious provision to be considered for reasonable spare capacities in

various system and system components and interchangeability of

equipment/ system. State of art technology has been considered for

design of the proposed system.

5.1.1 Steam Generating Unit & Auxiliaries

1. The steam generating unit is sized for 810 tphr. steam flow

(minimum) at 155 kg/cm2 (g) minimum super heater outlet steam

pressure and 540(5)C steam temperature re-heated steam

flow at RH out let 37.31 kg/cm2(g) pressure 540+50C

temperature at MCR with specified coal. This will ensure

adequate margin over the requirement of Turbine at 100% MCR

to cater for:

i) Auxiliary Steam requirement for atomization of fuel oil,

soot blowing operation, fuel oil system.

ii) Derating of the steam generating units with ageing,

covering VWO flow of steam turbine.

The steam generator will be semi-outdoor, natural circulation,

radiant reheat, dry bottom, balanced draft, single drum type unit

designed for firing pulverized coal as prime fuel. The complete

furnace section will be of welded membrane well construction,

arranged as a pressure tight envelope with requisite number of


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tilting tangential burners, (in case of corner fired) or fixed,

horizontal turbulent burners, (in case of front/rear end fired).

Each steam generator will be designed to operate with "the HP

Heaters out of service" condition (resulting in lower feed water

temperature at Economizer inlet) and deliver steam to meet the

Turbo generator requirement at 100% MCR. The steam

generator will be suitable for operation with 60% capacity HP-LP

Turbine bypass system envisaged for Turbo-generator.

All the pressure parts of main boiler section will be in

accordance with the latest applicable IBR. The material used for

pressure parts will be in accordance with the codes and

standards.

The complete furnace section will be of welded wall type

arranged as a gas and pressure tight envelop circulation system

will be complete with necessary number of unheated down

comers, supply and riser piping.

Super heated steam section will consist horizontal LT super

heater section, pendent radiant platen super heater and final

pendent super heater. Adequately sized de-super heater will be

provided in between LTSH and platen super heater for control of

final super heater steam temperature.

Re-heater will be arranged in one section in between radiant

super heater and final super heater section. Reheater –

desuper heater are envisaged in emergency at inlet to reheater

for use during any abnormal emergency conditions.


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Economiser will be arranged in between LTSH section and

regenerative air heater.

Each steam generator will be designed for continuous operation

while burning 100% coal and with coal burning along with oil

support for flame stabilization at low loads. Adequate number of

coal burners at various elevator levels with four burners at one

level fed from boiler mills will be provided. Steam Generator

will be designed so as to not require oil support for flame

stabilization beyond 40% BMCR when firing worst coal and to

minimize the use of fuel oil. The steam generator and its

auxiliaries will be sized suitably such that the Unit could operate

in synchronism with interconnected electrical network at

frequency which may go as low as 47.5 Hz.

All provisions in the steam generator design and fuel firing

system will be made to reduce the NOx emission from steam

generator which will not be more than 650 mg/Nm3 at the ESP

outlet at 6% oxygen. The Nox calculated includes that from fuel

as well as thermal Nox.


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5.1.2 Boiler Air & Flue Gas/Draft System

a) Air Heaters

The boiler furnace and flue gas passages will be designed for

low gas velocity of 10 m/s to minimize erosion and slagging

effect.

Air pre-heaters will be rotary regenerative type with electric

motor as main drive and air motor as standby drive will be

provided for each boiler at back end of the boiler connected with

gas duct. Each air pre-heater will be for 60% Boiler MCR load.

Two (2) nos. Steam Coil Air Pre-heaters (SCAPH) will be

located in the secondary air by pass ducting, in between FD fan

and regenerative air heater. SCAPH will be used to heat up air

entering the regenerative air heater to prevent any possible low

temperature corrosion by maintaining cold end temperature

above acid dew point during boiler start-up and low load

operating conditions.

Regenerative air heater proposed will be of tri-sector type in

which the primary air and secondary air are independently

heated in the same heater. In this type of air heater, the heating

surface and alternatively heated up by flue gas passing through

and cooled by air passing over its. The heat is absorbed by

heat transfer matrix from the flue gas and then released to air.

The regenerative air heater will have gas tight insulated casing

and rest on necessary steel structure. The system will be

complete with lubricating oil system, cleaning & washing drives,

control systems.


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b) Draft System

Each boiler will be provided with suitable draft system having

two (2) 60% rated centrifugal/axial, reaction type Forced Draft

Fans (FDF) with silencer and two (2) 60% rated radial

centrifugal type double suction Induced Draft Fans (IDF), with

inlet damper control.

Suitability of radial fan vis-à-vis axial fan for ID fan application

indicates that aerofoil centrifugal fan can operate with better

efficiency. The aerofoil blade shapes minimize turbulence and

are of low noise characteristics. The blades and centrifugal can

be fitted with wear plates and replaceable section for greater

wear protection. The blade shape minimizes dust build up and

reduces down time for cleaning.

The ID fans will be coupled to electrical motor drives through

hydraulic coupling for optimizing power consumption. Fans will

be provided with margin on flow and head of not less than 20%

and 40% respectively.

Primary air fans will be 2x60% capacity axial reaction centrifugal

type.

c) Safety Valves & Vents

- Safety valves will be provided at high temperature super

heater outlet, steam drum, reheater inlet & outlet.


Sheet - 26



- Start up vents will be provided at reheater & superheater

headers.

- Blowdown & flash tank unit complete with blowdown

recovery system etc. will be provided.

d) Soot Blowers

Each boiler will be provided with a set of soot blowers, which will

be automatic, sequential, electrically operated type, arranged for

on-line cleaning of the furnace, super heaters, reheaters, air

heaters economiser. Steam for the soot blowing system will be

from PRDS system. The soot blowing system will comprises of

long retractable soot blower wall blower (for furnace) a rotary

swivel arm type for air pre-heater. The system will be complete

with piping, valves and fittings etc.

e) Structural Works

The complete boiler will be top supported type with all

supporting structural steel, columns, duct pressure part

supporting column, beam, bracings ceiling girders and all inter

connecting members. A system of platforms & galleries and

access to various parts of the unit will be provided. Stairways

will be arranged for both sides of boiler.

Adequate weather protection will be provided to cover boiler roof, drum

level, burner operating floor, feeder floor and for instruments and

operating personnel. Necessary lining and insulation alongwith fixing

materials to limit outside surface temperature to a safe value are

provided.


Sheet - 27



5.1.3 Boiler Feed Pumps

The unit will comprise of 3x50% electric motor driven boiler feed pumps

per unit with the booster pumps mounted on the common shaft. Each

pump will be designed to give parameters to suit the steam generator

requirements. The feed pump will be able to handle feed water of pH.

8.5 to 9.5 and of temperature upto 185 deg. C (tentative).

The boiler feed pump will be of horizontal, centrifugal type. The boiler

feed pump outer casing will be of barrel type with end removal. The

inner pump assembly comprising of shaft, impellers, stage casings will

be capable of being removed and replaced as a unit without disturbing

the feed piping. Each feed pump will be equipped with mechanical seal

at drive end and non-drive of the shaft. The pump will be of robust

construction and does not require warm-up. The shaft of booster pump

and the electric drive motor, drive motor and gear box, gear box and

boiler feed pump will be connected by diaphragm type dry coupling.

The boiler feed water system will be designed to operate primarily in an

automatic mode over the range of system design loads. The

arrangement will provide automatic start-up one of the standby feed

pump under conditions like tripping of the running BFP’s and/or

discharge header pressure low etc.

5.1.4 Pulverizing Plant

Comparison of use of tube mill & bowl mill is given in Table.

Sr. No.

Description Bowl Mill

Tube Mill

1. Advantages * Simple to operate

* Less noisy

* Robust Mill * High availability


Sheet - 28



* Less rotating parts * Less no. of auxiliaries

&Excellent response to load changes due to large quantities of pulverised coal readily available.

* Clean environment due to no Mill rejects -(No reject handling system required due to the inherent design)

* Can handle high abrasive coal,

* Balls can be added on line

2. Disadvantages

* Reduction in output with Rollers wear

* For wear part replacement mill shut down is required

*Reject handling system required

*Continuous monitoring required

* High Power Consumption and extra control logics

* Consumption of grease which, cannot be used.

* Occupies more

space

3. Customer Trends

Customers operating Bowl Mills prefer to go for Bowl Mills for the reason that: * Low cost * Low Power

Consumption

*Occupies lesser space

Tube Mill users, like APSE (APGENCO), RSEB (RRVUNL), HSEB (HSPGCL), DVC etc., have consistently gone for Tube Mills


Sheet - 29



Each steam generator will be provided with “n” number operating + one

(1) as standby mills, while generating at BMCR with worst coal. Coal fed

size to mills will be (-) 25 mm.

The pulverizer and its motor will be capable of being started after having

tripped without removing the coal contained in the pulverizer. The

equipment will be designed to operate over a wide range of capacity to

minimize start-stop during load changes. All wearing parts will be

arranged such that they are replaced easily, without total dismantling of

the pulverizer. Design will be such that heavy parts can be handled easily

for maintenance purpose.

Adequate instrumentation for safe operation of the pulverizer will be

furnished. Suitable primary airflow measurement device will be

provided at air inlet of each pulverizer.

Shut-off gates of sturdy construction will be provided at outlet of each

raw coal bunker. These gates will be motor operated from the

operating floor level and ensure dust tight enclosure. In addition to

isolation gates, rod gates will also be provided to control coal flow from

bunker.

Coal chutes of approved type and size will be provided between raw

coal bunker shut off gate and inlet to the coal feeder and from feeder to

the pulverizers. Height of coal chute between bunker outlet and feeder

inlet will be adequately maintained to prevent hot air to come out.

Material of chute will be stainless steel. Coal chutes will be provided

with poke holes. An emptying chute, suitable for loading trucks at

ground floor, will also be provided.


Sheet - 30



Apart from the pulverizers, boiler unit will be equipped with gravimetric

raw coal feeders. Mill reject handling system of adequate capacity will

be provided.

Primary Air Fans and seal air fans of adequate capacity will be complete

with necessary ducting, local instruments, valves, suitable for remote

operation from the control room, etc will be included with the sealing

system designed so as to prevent any leakage of coal dust into the

bearing and atmosphere.

The pulverized coal will be conveyed to the PC burners at Boiler

corner/front/rear. Adequate number of fuel oils burners for `start up’

and low load operations’ will be located between the PC burners.

5.1.5 Electrostatic Precipitator

Each steam generating unit will be provided with 2 Nos. electrostatic

precipitators comprising of eight sections in the directions of gas flow

and two bus section perpendiculars to gas flow for collection of fly ash.

The ESP will have a collection efficiency of around 99.9%. The outlet

dust concentration from the chimney will be limited to 100mg/N cu.m

with one field out as per the latest regulation of Central Pollution

Control Board. Each ESP will be provided with adequate number of

ash hoppers having capacity suitable for storing ash collected in at

least one (1) shift operation of the Boiler at 100% MCR.

ESP will be complete with insulators, gas distribution screens, gas

screening plate, high voltage emitting system, collecting electrodes

system, rapping mechanism and transformer rectifier units etc.


Sheet - 31



The ESP will be equipped with microprocessor based control/ EPIC

controllers or approved equal means to restrict the power consumption.

The typical technical parameters and features of the boilers of 250 MW

unit are given in the following table:-

Boiler

1

2 3

Particulars (per boiler) Units Parameters at BMCR

Super heater outlet steam flow tph

810

Steam pressure at SH outlet

Kg/Sq.cm(g) 155

Steam temperature at SH outlet 0C 540+5

Reheat steam flow Tph 700

Steam temp. at RH inlet 0C 343.0

Steam temp. at RH outlet 0C 540+5

Steam pressure at RH inlet

kg/Sq.cm(g) 39.3

Steam pressure at RH outlet Kg/Sq.cm(g) 37.2

Feed water flow Tph 810

Drum pressure Kg/Sq.cm(g) 169.5

Feed water temperature at Ecco. Inlet

0C 247

Flue gas outlet temperature at ESP inlet

0C 140

Excess air(at 100% MCR) % 20%

Superheat temp control By spray

RH control

By burner tilt + spray + excess air adjustment.

FD Fans

Nos./Type 2 Nos. axial reaction type blade pitches controlled with silencer & drive motor.

ID Fans Nos./Type 2x60% double suction


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1

2 3

radial fans with inlet damper and hydraulic coupling & drive motor.

PA Fans Nos./Type

2x60% axial reaction fan with blade pitch controller with silencer and drive motor.

Soot blowers

As Per manufacturers design

Regenerative pre-heaters Rotary type bisector/ tri-sector electric motor driven. Auxiliary drive: Air motor

Ambient air temperature

(i) Maximum

(ii) Minimum

(iii) Reference temperature for Electrical Equipment

0C

0C

48.5 6.5 50

Efficiency at MCR More than 86%

Boiler Feed Pump

Number per boiler :

3x50% Electric motor driven (2 working + 1 standby)

Type :

Multistage barrel type horizontal, with booster pump


Sheet - 33



5.2 Steam Turbine Generator Unit 5.2.1 Steam Turbine

The each steam turbine 250 MW MCR will be three cylinders, (one HP,

one IP and one LP cylinders), high pressure 3000 RPM, multistage,

tandem compound, single reheat, condensing reaction turbine unit with

six (6) uncontrolled extractions for regenerative feed water heating &

steam sealings. The HP and IP cylinder will be single flow type and LP

cylinder will be double flow type.

The Turbo-generator set will be designed for a minimum throttle steam

flow at Turbine valve wide open (V.W.O.) condition of 105% of Turbine

MCR condition. The turbine will be rated for a minimum of 250 MW and

will be capable of both constant and variable pressure operation as

well as with both HP heaters out.

5.2.1.1 HP Turbine

The HP turbine will be designed with single flow. This will have a

double - shell casing consisting of axially split inner shell enclosing the

rotor and barrel-type outer shell. Main steam to the HP turbine will be

supplied through two combined stop and control valves. The exhaust

branch will be located below the turbine.

5.2.1.2 IP Turbine The IP-turbine will be designed with single flow. This will have a double

- shelled casing with horizontally split inner casing, and outer casing.

Reheat steam will be admitted through two combined stop and control

valves of the IP turbine. The valves will be arranged on either side of IP

casing. The exhaust branches will be on the top of the casing.


Sheet - 34



5.2.1.3 LP Turbine

The LP turbine will be double flow type horizontally split fabricated LP

casing of multi-shell constructions. The casing of LP turbine will be

connected to IP cylinder by two cross over pipes.

5.2.1.4 Blading

The entire turbine stage of HP Turbine will be provided with reaction

blading LP parts will have inverted T-roots and shrouding. The last

stage of LP moving blades will be of twisted and will have no lacing

wires or shrouding. They will be drop forged and will have fir-tree roots

that will fit into similar grooves in the rotor. Guide blades of HP & IP

will be with inverted T-roots and shrouding. The guide blades of the

last three stage of LP turbine will be of fabricated construction.

5.2.1.5 Valves

The HP-Turbine will be fitted with two combined emergency stop valve

and control valves for main steam admission. Two combined stop and

control valves will be installed at the IP-Turbine for hot reheat steam

admission.

Each combined valve consists of a stop valve and a control valve that

will be mounted on a common body. Every stop valve and control

valve will be equipped with separate Electro-Hydraulic-Actuator. The

main steam valves will be directly mounted on the HP-turbine.


Sheet - 35



5.2.1.6 Gland Steam Sealing System

A fully automatic gland sealing steam supply system will be provided

for the TG Set. HP & IP turbine shaft glands will be sealed to prevent

escape of steam into the atmosphere and the LP turbine glands will be

sealed for preventing leakage of atmospheric air into the turbine.

Steam will be used for sealing these spring backed labyrinth glands.

All shaft glands, sealing the steam in the cylinders will be of the axial-

flow labyrinth type.

During start-up and low loads seal steam will be supplied to the turbine

glands from the auxiliary steam header or cold reheat line through a

seal steam regulating valve. During normal operation, the HP and IP

turbines will be of self-sealing type and under that condition the

auxiliary / CRH steam source will be cut off and the leak-off steam from

HP and IP glands will be used for sealing the LP glands. The excess

leak-off steam will be led to the condenser.

A gland steam condenser will be provided to condense and return to

the cycle, all gland leaks off steam. Gland steam condenser will be of

surface type design. 2x100% capacity air exhausters will be provided

to remove non-condensable gases from the gland steam condenser.

The exhaust gases will be led over the TG hall roof level.

The turbine will have an over speed limit of (+) 10%, the critical speeds

being at (-) 15% below and (+) 15% above the normal speed while the

turbine blades are tuned for a frequency variation from (+) 3% to (-)

5%.


Sheet - 36



5.2.1.7 Bearings and Couplings

The journal bearings and one combined journal & thrust bearing will be

used for supporting the turbine shafting system. The combined journal

and thrust bearing at the rear of the HP turbine comprises a self-

adjusting journal bearing and a thrust bearing to accept the unbalanced

residual thrust. The other journal bearings will also be of the self-

adjusting type. Bearing temperatures will be acquired by

thermocouples located directly under the white-metal lining of the

bottom shell in the journal bearings and in two diametrically opposed

pads in the thrust bearing.

The individual turbine shafts will be rigidly coupled together by means

of integral flanges.

5.2.1.8 Turbine Oil System

The oil system will supply oil for lubrication and cooling of turbine and

generator bearings, and to the hydraulic shaft turning gear during start-

up and shutdown. This system will be provided with AC & DC powered

oil pumps. To improve lubrication of the bearings during start-up and

shut down, a jacking oil system will be installed which also supplies

motive oil to turning gear.

A separate, self contained high-pressure fluid system with dedicated

pumps will be provided for valve actuation. The system will specifically

include the following:

(a) The main oil pump will be centrifugal/gear type. The turbine

shaft will directly drive it. It will have sufficient capacity to handle


Sheet - 37



lube oil requirement of the bearings and emergency seal oil

requirements.

(b) 2 x 100% AC aux. Oil pumps for start-up, slowdown of TG unit

and as standby to MOP for automatic operation. These pumps

will be in service during start up till the main oil pump takes over

the supply.

(c) 1x100% DC emergency oil pump for meeting lube oil

requirements of bearings during emergency with automatic

starting on low lube oil pressure preset value.

(d) One (1x100%) each AC & DC motor jacking oil pumps will be

provided to lift the rotor at the bearing during turning gear

operation.

(e) Seal oil pumps to supply oil for generator seals by separate AC

driven oil pumps.

(f) Oil tank of sufficient capacity for oil changes. 2x100% duty

vapour extraction fans. The 2x100% capacity oil coolers will be

provided for oil cooling.

(g) A lube oil purification unit will be permanently installed for each

unit for the total oil charge on a continuous basis.

5.2.1.9 Governing Systems

The turbine will be equipped with two channel digital turbine controller

ensuring stable operation under all operating condition, including grid

disturbances and level throw off condition. The turbine governing

system will be designed for high accuracy, high operating speed and


Sheet - 38



sensitivity. It permit governed run up to rated speed of the turbine. The

linear power output/frequency characteristics will be adjusting between

close limit while machine is in operation.

5.2.1.10 Turbine Drain System

To avoid thermal stress and possible deformation of the turbine casing,

the condensate produced by the condensing steam during warm up of

the turbine will be discharged into the condenser.

5.2.1.11 Turning Gear

High speed hydraulic turning gear is envisaged to ensure uniform and

rapid heating/cooling of casing during start up/tripped conditions.

Manual turning gear will also be provided in addition to the hydraulic

turning gear.

5.2.1.12 HP - LP Bypass Station

60% H.P. and L.P. Turbine bypass station will be provided to act not

only as a protection to the turbine during pressure rise resulting from

sudden load throw-off but also to enable operation of the unit at loads

lower than the control load. Further HP/LP bypass will permit quick,

repeated hot starts of the unit on its tripping.

The LP bypass station will be connected to the hot reheat line and

discharges the steam into the condenser. The hot reheat steam will be

desuperheated by means of condensate injection. The bypass system

shall be in operation when the steam turbine is not able to receive the

entire steam quantity, e.g. during start-up or in case of a load rejection.


Sheet - 39



The HP and LP bypass stations will be capable of meeting the

following requirements:

(a) Quick start up of the steam generator from cold, warms & hot

conditions.

(b) Parallel operation of the bypass with turbine under large load

throw-off.

(c) House load operation followed by large load throw-off.

(d) To keep the steam generator in operation so as to avoid a fire

out in the steam generator following full load rejection.

5.2.2 Condensing Equipment

1. The function of the condenser is to condense the steam

exhausted from the LP cylinders and to produce and maintain as

high a vacuum as possible in order to increase the enthalpy

drop, which can be utilised in the turbine.

2. The condenser will be a two pass single shell surface type, box

type construction with divided water box design. The steam

space will be of rectangular cross-section to achieve optimum

utilization of the enclosed volume for the necessary condensing

surface. The condenser will be located below the LP turbine and

form an integral part of it.

3. The steam dome, shell and hot well are steel fabrications, as are

the water boxes. The condenser will be fixed supported on the

foundation beneath.


Sheet - 40



4. The LP turbine outer casing will be connected to the condenser

through the steam dome. The steam dome will be welded to the

exhaust casing of the turbine with the result that the LP turbine

cylinder and the condenser form a unit.

5. The direction of circulation water flow will be at right angle with

the turbine axis and in one pass. The condenser tube bundles,

on which the exhaust steam from the turbine condenses, will

consist of straight tubes with smooth surfaces and running right

angle with the turbine axis in the steam space of the condenser.

The condenser tubes rest in tube support plates at regular

intervals along their length to prevent impermissible tube

vibration when the condenser is in service. Tube sheets on the

circulating water inlet and outlet sides will act as partitions se-

parating the steam space from the cooling waterside. Both ends

of the tubes, through which circulating water flows, are roller-ex-

panded into the tube sheets. On the cooling waterside the water

boxes will be provided with a coating to prevent contact

corrosion.

6. The condenser tubes will be divided into tube bundles designed

to promote uniform flow. Tubes will be of stainless steel. The

following general aspects of possible improvements will be

considered:

Lowest possible condenser inlet pressure influenced by

the pressure drop between the LP-turbine diffuser and

condenser tubes, the heat transfer coefficient of the tubes

and the activation of the entire heat-exchange surface.

Smallest possible condenser heat losses.

Minimized oxygen content in the condensate


Sheet - 41



7. Motor operated butterfly valves and expansion joints will be

provided at both CW pump and condenser ends. Condenser

circulating water piping will be arranged for two inlets at the top

and two outlets at the bottom. Cleanliness factor for condenser

design will be 85 percent while oxygen content of hot well water

will be maintained around 0.005 cc/liter. On load tube cleaning

equipment will be provided to minimize tube deposit even while

operating. Hotwell capacity will be equivalent to 5 min. duration.

The temperature rise of circulating water will be limited to 10.0C

max. with under the rated steam entry into the condenser.

Water velocity through tubes will be limited to 2 m/s. The

circulating water will be drawn from the circulating water sump.

Arrangement for on load maintenance of condenser will be

provided.

5.2.2.1 Air Extraction

The unit will comprise of (2x100%) vacuum pumps along with all

accessories and instrumentation for condenser air evacuation. The

vacuum pumps and accessories will be used to create vacuum by

removing air and non-condensate gases from steam condenser during

plant operation. Vacuum pumps will be of single / two stage liquid ring

type with rotor eccentric to the casing with both stages (if two stage

pump is selected) mounted on a common shaft. Vacuum pumps will

be sized as per latest HEI requirements.

5.2.2.2 Condensate Pumps

Each unit will have 3x50% capacity motor driven condensate extraction

pumps (two operating and one standby). The condensate pumps will

be vertical canister type, multistage centrifugal diffuser design with a


Sheet - 42



double suction first stage designed for condensate extraction service

having low suction head requirement. The pumps will be capable of

handling the condensate from the condenser together with feed heater

drains when the machine is operating at maximum unit output with HP

Heaters out with 3% make-up and discharging this quantity through the

LP heaters to the deaerator. The pump will have adequate margins on

capacity and head to cater for most adverse conditions of operation

such as:

a) HP & LP bypass in operation.

b) HP heaters out of service and unit operating at its maximum

load during an under frequency operation.

5.2.3 Regenerative Feed Heating Cycle

Regenerative feed heating system will be designed for all operating

conditions including transients like sudden load throw-off, HP-LP

bypass in operation, one or two heaters going out of service etc. The

condensate from the condenser will be pumped by the condensate

extraction pumps through the train of LP heaters to the deaerator. In

deaerator, the condensate will be heated to saturation temperature and

fed to the boiler feed pump, which increases the feed water pressure to

suit the steam generator requirements. Finally the feed water is fed to

the boiler through a feed regulating station.

5.2.3.1 LP & HP Heaters

Regenerative feed heating cycle will consist of three LP heaters, one

drain cooler, gland steam condenser, deaerator and two HP heaters.


Sheet - 43



Three (3) low-pressure horizontal feed water heaters will be provided.

The LP heater 1 will be mounted in the condenser neck and uses an

external drain cooler. The LP heater 1 will be individually isolated and

bypassed. LP heater 2 and LP heater 3 will be equipped with integral

drain cooling and condensing zones and will be provided with a

common isolation and bypass.

Two (2) high-pressure horizontal heaters will be provided with both

drain cooling and desuperheating zones in addition to the normal

condensing zone. Both HP heaters will be provided with individual

bypasses to allow isolation and maintenance. Group protection will be

provided.

Feed water will be heated by uncontrolled turbine extraction steam

from turbine inter-stage tap-offs and cold reheat line in feed water

heaters. The equipment will be designed in accordance with latest

applicable standard / codes of heat Exchanger Institute. ASME, IBR

etc. The feed water heaters will be of U-tube with all welded stainless

steel tubes, surface type and horizontal with integral condensing and

drain cooling zones. The HP heaters will also have de-superheating

zone.

5.2.3.2 Deaerator

The deaerator is provided to remove the dissolved corrosive gas from

feed water. The deaerator consists of integral vent condenser

deaerating heater and feed water storage tank of adequate capacity.

Deaerator will be variable pressure spray-cum-tray type designed to

deaerate all the incoming condensate and drain flow to keep the

oxygen content of the condensate below the permissible limit of 0.005


Sheet - 44



cc/liter and Co2 will be reduced to traces. The deaerator normally

operates by taking extraction steam from the IP turbine except during

low load operation and start up when it is pegged with steam drawn

from the auxiliary steam header. Deaerator will be elevated to provide

sufficient NPSH for the boiler feed pumps. The deaerator and feed

water tank will be designed and constructed to international standard

like HEI, TEMA, ASME Section-VIII Division-I etc.

5.2.4 The brief typical turbine parameters of 250 MW unit are as under:-

Turbine

Unit At TMCR

Type - Tandem Compound

Number of cylinders - Three (3)

Type of governing - Electro hydraulic

Speed RPM

3000

Rated output (continuous) KW 250,000

Steam pressure before emergency stop valve

Kg/cm2 150

Steam temperature before emergency stop valve

0C 537

Reheat steam inlet pressure Kg/cm2(g 35.7

Reheat steam temperature 0C 537

SH Steam flow required with 0% make-up

tph 737.6

Reheat steam flow tph

663.3

Rated pressure at exhaust of LP turbine

ata 0.0992

Rated quantity of circulating water to condenser

M3/hr 33,000

Maximum temperature rise of circulating water

0C 100C

CHHATTISGARH STATE POWER GENERATION COMPANY LIMITED

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