TD

Bangladesh Power Development Board

Extension of Barapukuria Coal Fired Thermal Power Station by 250 MW (3rd Unit) Tender Documents Part B

Technical Requirements

Volume 1 of 2

1

B0 General Specification 0.1 Subject of Specification 0.2 General Auxiliary Systems 0.2.1 Purpose of the Plant 0.2.2 Site conditions- environmental conditions 0.2.2.1 Location of site 0.2.2.2 Transportation and access road for site 0.2.2.3 Meteorological condition 0.2.2.3.1 General 0.2.2.3.2 Rainfall 0.2.2.3.3 Temperature and humidity 0.2.2.3.4 Earthquake 0.2.2.3.5 Wind 0.2.2.3.6 Flood water level condition 0.2.2.3.7 Geological conditions 0.2.3 Layout 0.2.4 Configuration 0.2.5 General technical requirements of the Plant 0.2.5.1 Design requirements 0.2.5.2 Outline description of generating facilities 0.2.5.3 Main powerhouse including control building 0.2.5.4 Civil 0.2.6 Mode of operation 0.2.7 Environmental conditions and emission control standards 0.2.7.1 Environmental conditions 0.2.7.2 Ambient standards and emission standards 0.2.8 Fuel 0.2.8.1 Characteristic of coal

2

0.2.8.2 Ash

3

0.2.9 Waste and waste water 0.3 Supply and Services 0.3.1 General 0.3.2 Scope of engineering services 0.3.3 Common equipment 'and services 0.3.3.1 General 0.3.3.2 Mechanical 0.3.3.3 Electrical, instrumentation and control 0.3.3.4 Civil 0.3.4 Packing and transportation 0.3.5 Documentation 0.3.5.1 Documentation with Tender 0.3.5.2 Documentation after award of Contract 0.3.5.3 Requirements for documentation:: 0.3.6 Erection, commissioning and testing 0.3.7 Training of Employer's personnel 0.3.7.1 General 0.3.7.2 Training in the Contractor's country 0.3.7.3 Training at site 0.3.8 Spare parts, tools, appliances, and consumable 0.3.8.1 Spare parts 0.3.8.2 Tools and appliances 0.3.8.3 Consumables 0.3.9 Maintenance works 0.3.10 Options 0.3.10.1 Option: Later realization of Power Unit 3 0.3.10.2 Option: l-.Maintenance works of the whole Plant 0.4 Interfaces

4

0.4.1 Limits of supply

5

0.4.2 Interfaces to existing facilities on site 0.4.3 Metering 0.4.4 Communication systems 0.5 Form sheets (Data Sheets) 0.6 General Technical Requirements 0.6.1 General requirements 0.6.2 Standards and codes 0.6.3 Plant and equipment identification (e.g. Power Plant Coding System KKS) 0.6.4

Marking and labeling of crates and packages

0.6.5

Corrosion protection coaling and galvanizing

0.6.6

Vibration

0.6.7

Standardization of makes

0.6.8

Accessibility

0.6.9

Signs

0.6.10 Units of measurement 0.6.11 Ways, stairs, ladders, balustrades 0.6.12 Hazardous areas fire protection provisions 0.6.13 Maintenance isolation 0.6.14 Materials 0.6.15 Pre-service cleaning and protection of plant equipment 0.6.16 Mechanical equipment 0.6.16.1 Pumps 0.6.16.2 Piping and accessories 0.6.16.2.1 Standards and general conditions 0.6. 16.2.2 Material and construction standards 0.6.16.2.3 Bolts and nuts 0.6.16.2.4 Pipe supports and anchors 0.6.16.2.5 Cleaning at workshop

6

0.6.16.2.6 Cleaning at site 0.6.16.2.7 Wall boxes and collars 0.6. 16.2.8 Expansion and flexibility Piping design criteria 0.6.16.3

Welding and heat treatment

0.6.16.4

0.6.16.4.1 Responsibility Required documents

0.6.16.4.2 0.6. I 6.4.3

Welding procedure qualification Personnel qualification Welding process

0.6.16.4.4 0.6. 16.4.5 0.6.16.4.6 0.6.16.5

Pre-heating and heat treatment 0.6. 16.4.7 Documentation Valves, steam traps, condensate drainers, safety valves, control valves

0.6.16.6 Insulation 0.6.16.7 Vessels, tanks, heat exchanger 0.6.17 Electrical equipment and works 0.6.17.1 0.6.17.2 0.6.17.3 0.6.17.4 0.6.17.5

Standards Standard Climatic

voltages conditions

Inductive interferences Color code system for switchgear, for local switching measurementcontrol-signaling cabinets and for mimic diagrams

0.6.17.6 Protection class for electrical operational equipment and control and monitoring equipment

0.6.17.7 Protective measures 0.6.17.8 Auxiliary equipment

0.6.17.9 Requirements for local cubicles and local housings for e.g. switchgear, control, measurement and signaling equipment 0.6.17.10 Local control points and level control cabinets 0.6.17.11 T erminal boxes and terminal cabinets 0.6.17 .12 Explosion proof equipment 0.6.17 .13 Keys and key cabinets 0.6.17. I 4 Electric motors 0.6.17.14.1 High voltage motors 0.6.17 .14.2 Low voltage AC motors 0.6.17 .14.3 Actuator drives 0.6.17.14.4 DC motors 0.6.17.14.5 Painting 0.6.17 .14.6 Protection against explosio n hazards 0.6.17.14.7 Frequency converters 0.6.17 .14.8 Tests 0.6.17 .14.9 Motor list 0.6.17 .14.10 Labels 0.6.18 Instrumentation and control 0.6.18.1 Measuring units 0.6.18.2 Sizes of indicators, recorders, etc. 0.6.18.3 Protection and safety interlocks

0.6.18.4 Special local conditions 0.6.18.5 Tests 0.6.18.6 Field equipment 0.6.18.6.1 Measuring systems/tr ansmitte rs 0.6.18.6.2 Flow measurements 0.6.18.6.3 Temperature measurements 0.6.18.6.4 Pressure measurements

0.6. 18.6.5 Analyses meas urem ents 0.6. 18.6.6 Level meas urem ents 0.6. 18.6.7 Electrical meas urem ents 0.6. 18.6.8 Position meas urem ents 0.6. 18.6.9 Contact devic es 0.6.18.6.10 Vibration meas urem ents. 0.6.18.6.11 Control valve s 0.6.18.6. 12 Actuators 0.6.18.6.13. Local instru menta

tion 0.6.18.7 Racks, junction boxes 0.6.18:8 Control cubicles 0.6.18.9 Programmable logic controller 0.6.18.10 T ransmitter racks and piping 0.7 Inspection and Testing 0.7.1 General 0.7.1.1 Workshop manufacturing and pre-assembly 0.7.1.2 Works inspections 0.7.2 Testing during manufacturing 0.7.2.1 Material tests 0.7.2.2 Tests at site 0.7.2.2.1 General remar ks 0.7.2.2.2 Hydraulic tests 0.7.2.2.3 Test runs and functi onal tests 0.7.2.2.4 Visual ins pec tion , che cki ng of dim ens ion

s, test inst ru me nts 0.7.2.3 Manufacturing tests 0.7.2.3.1 Welding 0.7.2.3.2 Pressure testin g 0.7.2.3.3 Testing of cor rosi on pro tect ion

0.7.2.4 Mechanical equipment 0.7.2.5 Electrical equipment 0.7.2.6 Control and monitoring equipment

Table of Contents of the Tender Documents, Part B •

Section B0: General Technical Specification

•

Section B I : Steam Generator Plant

•

Section B2: Steam Turbine Plant with Condensate and Steam System

•

Section B3: Coal Handling System

•

Section B4: Air and Flue Gas System

•

Section B5: Ash Handling System

•

Section B6: Water Storage and Treatment Systems

• •

Section B7: Auxiliary Systems Section B8: Electrical and Associated Works

•

Section B9: Instrumentation and Control Works

•

Section B 10: Communication, Clock and Surveillance Systems

• •

Section B11: Civil Works Section B12: Workshops, Stores and Vehicles

•

Annexes

General Specification

B0. General Specification 0.1 Subject of Specification This section forms an integral part of the Tender Documents issued by the Bangladesh Power Development Board, Dhaka.

0.2 General Auxiliary Systems All the auxiliary systems needed have to be designed accordingly.

for

the

trouble-free

operation

of

the

unit

The main auxiliary common systems are listed hereunder: This list is not limited to the systems below, but the contractor has to supply, erect and commission all the general auxiliaries necessary for the operation of the unit at M.C.R: • • • • • • • • • • •

Coal Processing and Coal conveyor system Ash handling, ash transport and ash pond Raw water system, dc-mineralized water and potable water Waste water treatment system Pressurized air system Laboratory Auxiliary closed circuit cooling system The fire fighting system All ancillary buildings and services 6.6 KV and 440/220 V switch-gear rooms Switchgear room and "relay room'

0.2.1 Purpose of the Plant - intent It is the intention of the Bangladesh Power Development Board to install a thermal power plant unit for a total capacity of 250 MW at the Barapukuria Steam Power Plant, in order to meet the electricity power demand. The Plant shall be coal fired and equipped with reheater and all auxiliary and ancillary systems. The Contractor shall cover all works for the Engineering, construction and commissioning of the whole Plant on a turnkey basis.

procurement,

In order to transmit the generated electrical power to 230 kV grid network a step up power plant substation shall be included. The boilers shall be open-air installed for firing with coal. The steam turbine condensers shall be - water - cooled. In order to cool the condenser cooling water, cooling towers shall be constructed.

The equipment of the Plant shall be designed in accordance with the requirements contained in the Tender Documents and as illustrated on the Tender Drawings attached. Highest reliability and availability, convenience of operation and maintenance, neat and orderly arrangement, are of utmost importance. The functional requirements of the various systems and the pleasing physical appearance of the completed Plant shall also be taken into account. Due care shall be undertaken concerning the environmental impact out of the Plant and sufficient protective measures shall be incorporated in the design of the Plant for envirolUl1ent protection especially on air pollution, water pollution and noise. The environment protection measures shall be done in accordance with the Environment Protection Guidelines of UNDP, ADB, World Bank and Environmental Protection and Emission Control Standards of Bangladesh. In all instances, the listing of items of the Plant shall be understood as general, and shall include upon completion, even if not specifically mentioned, other necessary components and appurtenances required for proper, continuous and reliable commercial operation of the complete installation, including any and all auxiliary and ancillary systems.

0.2.2 Site conditions - environmental conditions The following information on local conditions is investigated or compiled by the Owner/Owner's Representative. The Contractor is hereby in no way relieved from his duties of carrying out the investigations required for satisfactory performance of his works, before issuing the Bid and during execution of the works.

0.2.2.1 Location of site Barapukuria power Plant site is located in flat land of the Northwestern "corner" of Bangladesh at about 45 km east of the district headquarters of Dinajpur, 20 km east to the border of India. The north-south gauge railway passes through the east part of the site. The site is located about 1 km north of the coal mine mouth under construction. The only large industrial residential complexes. The nearest administrative of the site.

area

nearby

is

this

coal

mine

including

its

town is Phulbari, a Thana (Upazila) headquarter as primary center of the country. Phulbari is located about 6 km south

The major railway junction and surrounding 16 km to site. The railway is connected to site.

township

Parbatipur

is

about

The Maddhapara Hard Rock Mining Project, trial project is located 12 km east of the site. To reach site from Dhaka normal climatic conditions.

by

car

needs

a

separate

approximately

large

scale

6

7

-

indus-

hours

at

The closest airport to site is Saidpur. It takes about 1 hour by car from site to the airport. The airport is in operation now. Metalled site.

road

is

connecting

Dinajpur,

Phulbari,

Parbatipur,

Saidpur

and

The area is situated at approximately 30 m over sea level. The groundwater flow goes from north to south. For cooling, industrial and housing purposes of the existing 2x125 MW plant, the ground water is being pumped from deep wells gathering area at north of site. Discharge water from coal mine after required treatment will be used as cooling water and the existing deep tube well water will be used for potable water & demi water production of the proposed 250 MW. The waste water/sewage water after suitable treatment shall be dumped in a soakaway at the south site of site. The bottom ash from the boiler and the fly ash from boiler &electrical precipitator shall be dumped in a pond on site. These ashes shall be transported wet and during the dry time of the year the ash shall be wetened by water. The water leaving the pond shall be treated in such a way that it will be suitable for irrigation or for pumping away to the nearby river Tillay. A dry ash conveyor transportation and dumping system shall be considered as an option.

0.2.2.2 Transportation and access road for site Access road for site for the facility of transportation, a metal road from the end of Parbatipur/ Fulbari up to Barapukuria Power Station site is being used. Transportation for construction and erection material In Bangladesh, inland transportation of all imported rail and road.

materials

is

done

by

In general, the ordinary equipment and materials can be transported to the requested places by road and rail. However, a bulk of heavy equipment and machinery such as Generator Stator, Steam Drum and etc. for the coal fired power Plant are difficult to transport to near the project site other than waterway. Loads probably more than 150 t will need to be transported for the Power Plant. A scheme that the Contractor of the Power Plant may consider most feasible would be to transport the equipment by river upto nearest possible location and then to transport by rail or road. The Contractor tender.

shall

fix

up

the

transportation

possibilities

in

detail

for

the

0.2.2.3 Meteorological condition 0.2.2.3.1 General Bangladesh has a subtropical monsoon climate and weather patterns are governed by the south-east Asian monsoon system. The year can be roughly divided into the rainy season from May through September and the dry season from October through April. Meteorological information relevant to the Barapukuria site is available from weather stations at Dinajpur (880 41'E, 25° 38'N) and Rangpur (89° 15'E,25° 45'N). These stations are about 30 km west and east respectively from the Plant site. The data are available at Bangladesh Meteorological Department.

0.2.2.3.2 Rainfall Rainfall from May through September contributes over 85% of the annual total. However, rainfall intensives tend to be high and concentrated in acomparatively small number of heavy storms, even when monthly rainfall figures are relatively low. The monthly precipitation data are as follows (in mm):________________________________________________________________

Average in Dinajpur

Average in Rangpur

Peak at one day

Maximum per month

January

11

6

February

13

15

March

16

27

April

70

110

May

241

307

85

307

June

297

499

140

700

July

592

660

142

640

August

442

430

132

442

September

307

412

431

890

October

144

120

104

242

November

7

7

December

16

17

2,008

2,812

Annual

Note: Above mentioned data are very old, probably in the period of 1981- 1988

0.2.2.3.3 Temperature and humidity The data of temperature and humidity are as follows: (According to the temperature data in 1988, the maximum temperature is 40°C and the minimum temperature 10.6°C. The mean temperature is about 25°C and relative humidity is generally high.)

Dinajpur Max. Temp. in '88 (0C)

Rangpur Min. Temp. in '88 (0C)

January

24.9

11.6

Feb.

27.5

14.2

March

33.5

April

Mean. Temp.81 - 88 (0C)

18.4

Mean Hum.'81 - 88 (%)

Max. Temp. in '88 (0C)

Min. Temp. in '88 (0C)

Mean. Temp.8 1 - 88 (0C)

Mean Hum.'8 1 - 88 (%)

70

25.3

11.7

16.8

79

70.9

61

29.0

145

19.0

71

13.5

25.4

54

33.7

12.6

23.6

63

40.0

10.5

28.0

57

37.5

16.8

26.5

69

May

36.3

19.0

28.2

70

35.6

20.8

. 27.3

79

June

37.5

23.8

29.0

76

36.3

23.9

28.7

84

July

34.0

23.0

28.5

82

34.1

22.5

28.4

87

August

36.7

22.1

29.3

82

32.4

26.2

28.8

85

Sept.

32.0

25.6

28.4

84

31.8

25.4

27.8

87

Octobe r

31.5

22.2

27.5

76

31.4

22.6

26.2

84

Nov.

28.8

16.4

23.7

70

28.3

17.5

22.1

79

Dec.

26.5

13.1

72

26.0

14.1

18.3

81

Annual

32.4

17.9

71

31.8

19. 1

24.5

79

19.6 25.6

0.2.2.3.4 Wind The wind in Barapukuria changes its direction according to seasons. The wind tends to blow from the west, or in dry season from northeast and from the east or the southeast in rainy season. The predominant wind direction is generally east-west. The wind speed is relatively moderate and it is said that there is also a high proportion of calm days through the year.

Monthly average prevailing wind speed (knots and direction/lknot = 0.514 mis) Rangpur (1979988)

YE AR 197 9 198 0 198 1 198 2 19& 3 198 4 198 5 198 6 198 7 198 8

JAN SPD DIR 3

N

FED

MAR

S

D I R N

SP D

APL

S P D 6

DI R NN W

SP D

MAY

JUN

SP D

DI R

SP D

5

D I R S

3

S

5

E

4

E

3

JUL SP D

4

DI R S E S E

E

3

S

n. a.

4

4

W

4

N E

4

E

3

4

N E

3

S

S

W

5

4

W

5

W

S

W

4

E

4

E

4

E

4

4

N E N E N E NN E N E N E

4

W

6

W

7

W

4

E

4

S E

4

4

W

S

S

4

E

4

E

5

E

5

6

E

5

E

6

E

5

S E

5

7

W

6

E

5

E

5

E

5

4 5 5 4 4

4 S

N E w

N E

4

4

N E

S

N E

6

E

5

S E

4

E

5

5

E

4

E

6

E

6

E

7

E

4

AUG D I R S E S E n. a. S E S E

SP D

S

6

S E E S E S E

5 4 n. a. 5 3

6 5 5 5

D I R S E S E n. a. S E S E S E S E S E S E S E

SEP SP D 5

OCT

NOV

D I R S

SPD DIR 3

N

3

N

3

S

4

N E

3

2

3

W

4

4

N E N E

4

SPD DIR

SP D

E

4

5

S

5

S

5

5

S E

4

E

5

N E N E N E N E N E N E

1

E

5

N E

5

E

4

4

E

4

E

4

4

4

S

5

N E

5

N E N E

3 n.a . 3 4

n. a. N E

4

4 4 3 5 4

4

2 2

Monthly average prevailing wind speed (knots and direction/1 knot - 0.514 m/sj

Dinajpur (1981 - 1988)

YEA R

JAN SPD DIR

198 1 198 2 198 3 198 4 198 5 198 6 198 7

6 3

FEU SP D

N W N W N W

MAR

APR'

SP D

7

DI R N W

DI R

8

W

4

W

3

3

W

SP D

MA\' SP D

8

DI R N E

W

3

4

W

IUN SP D

7

DI R N E

E

3

5

E

JUL SP D

6

DI R N E

E

3

E

3

E

2

AUG SP D

2

DI R N E S E

E

2

S

3

6

6 3

SEP

D I R N E E

NO\' DI R

SP D

2

D I R N

2

W

2

SP D

DI R

SP D

3

E

2

2

E

2

3

E

3

E

2

W N E

SP D

5

2

W

4

W

4

W

3

E

3

E

3

E

2

E

3

E

2

S E

2

E

2

3

W

3

W

5

W

3

E

3

E

2

E

2

E

3

E

2

E

3

E

2

N E N E N E

2

W

3

W

5

W

3

E

3

E

3

E

3

E

2

2

E

2

E

2

E

2

2

W

3

W

3

E

3

E

2

E

2

E

3

E

4

2

E

2

E

2

N E

2

2

S E

ocr

S E E

2 2 2

2 3

198 8

2

W

2

W

4

W

3

E

2

E

3

E

2

S

2

S

2

S

2

N E

3

N E

2

2 4

0.2.2.3.5 Earthquake General Bangladesh is historically less affected by earthquakes. During the last some one hundred years widespread damages were caused by only the Great Earthquake of 1897 which had its epicentral tract in the Shillong plateau. Two other major earthquakes, the Bengal Earthquake of 1885 and Srimangal Earthquake of 1918 caused severe damages only in limited areas surrounding their epicenters. The present geological information does not indicate existence of seismically active faults within the country. However, north and east of Bangladesh, there are areas of high seismic activity in India and Myanmar and earthquakes originating in these areas affect adjacent regions of Bangladesh.

Seismic zoning map According to the Final Report on "Seismic Zoning Map of Bangladesh and Outline of a Code for Earthquake Resistant Design of Structures (1979)", Bangladesh has been divided into three seismic zones. The Seismic Zoning Map of Bangladesh is shown in Annex. The northeastern part that includes the towns of Sylhet, Mymensingh and Rangpur are in Zone I, the most active seismic zone where earthquake shock of maximum intensity of IX of Modified Mercall Scale is possible. Zone II includes the towns of Dinajpur, Bogra, Dhaka and Chittagong. The project area is included in Zone II. The horizontal seismic coefficient = O. 15 g. Code for earthquake resistant design of structures The main aim of the code for earthquake resistant design of structures is to ensure that structures are able to respond to shocks of moderate intensities without structural damage. This code is meant only for normal buildings with height no more than 200 ft. In case of taller building, a dynamic analysis must be performed, with the ground acceleration inputs appropriate for the probable maximum intensity for particular zone. According to this code, the shear force at the base of a building is given by the following formula: v = Z.I.K.C.S. W Where Z

I

: Importance factor (1.5 for important facilities, 1.0 for others).

K

:

C

S

w

: Basic horizontal seismic coefficient (0.06 for Zone II)

Structural system factor (varies 0.67 - 1.33 according to structural systems).

: Structure flexibility factor (varies 0.20 - 1.0 according to the fundamental time period of a building) Soil foundation factor (varies 1.0 - 1.5 according to the combination of soil type and foundation type) : Design vertical load :

The maximum design horizontal seismic coefficient = 0.15 g shall be considered.

2 5

0.2.2.3.6 Flood water level condition The elevation of the site area is geodetically higher than the other parts of Bangladesh. Therefore, the flood damage is "less" than that of the other regions. According to the resident in the vicinity of the site area, the maximum flood level in 1988 was less than one meter above the ground level of that time. Accordingly, during construction of unit no. 1 & 2 the Plant area was filled approx. 2 m high from that ground level to protect the Plant facilities from the flood. For the flood protection, the railway is situated on an embankment which is 1.5 m to 2.0 higher than the ground level. Therefore major earthfilling is not required. However if ground level of any area of the proposed plant is found lower, it shall have to be filled up to the level of existing plant. Underground piping and cabling shall be installed in waterproof ducts which shall be equipped with lighting and fire alarms and which shall be accessible for the maintenance staff.

Geological conditions The stratigraphical sequence into the following groups:

has

been

divided

on

purely

litho

logical

grounds

Madhupur Clay (Recent - Pleistocene) Dupi (Tila Formations)

-Upper (Pliocene) - Lower (Pliocenelate Miocene)

Gondwana Group (Permian)

- Upper Coals Sequence Seam VI Sandstone Sequence Seam VI - Lower Sandstone Sequence Tillites -

Dasement (Pre-Cambrian) The outline of Madhupur Clay and Dupi Tila Formation are as follow: Bulk Density : 1.91 - 2.19 t/m3 a)

Madhupur clay The Madhupur Clay formation was found across the entire site beneath a thin soil horizon. It varies in thickness between 3 and 15 m, but is generally 10-12 m in thickness. Lithologically, the fonnation comprises series of firm and stiff silty clays interlaminated and interbedded with silts and siIty sands. The silt and sand horizons increase in frequency to the base of the formation. The geotechnical and hydrogeological characteristics of Madhupur clay are summarized as follows:

2 6

Shear strength of Madhupur clay Shear Resistance Angle

Cohesion (kN/m3)

30~85

Permeability:

9.79 x 10 - 5 - 5 X 10 - 7 m/s

Ph:

6.8 - 7.4

o CO CO

Undrained multistage triaxial test

i

119

o

b)

Shear box test

17°~ 11.6°

Dupi Tila formation Dupi Tila formation is divided into two groups, the upper and the lower. The upper Dupi Tila formation is dominated by sands between 94 m and 120 m in thickness. The lower Dupi Tila formation, which is dominated by clays, is located In the southern part of the coal deposit area and not present in the power Plant site. The upper Dupi into two main units:

Tila

formation,

with

the

average

thickness

of

107

m

is

divisible

The upper unit: average 65 m in thickness, of micaceous gray sands and gravels with occasional bands of silt and clay. The lower unit; approximately 40 m in thickness, of orangebrown, slightly micaceous sandstone, generally finer than the upper unit with more frequent thin beds of slit and clay.

The geotechnical and hydrogeological characteristics upper Dupi Tila formation are summarized as follows:

of

the

upper

part

Bulk density: 1.92~2.00 t/m3 Shear strength of upper Dupi Tila formation Cohesion (kN/m1)

Shear box test Triaxial test

Shear Resistance Angle 24.5°

Undrained multistage Consolidated drained

62

2° - 4° 2°

Unconsolidated undrained

16

27.5°

"3i o

130

• These tests were carried out on undisturbed samples of cohesive materials such as silt or clayey silt of the Upper Dupi Tila formation.

2 7

of

the

Permeability No permeability test has been permeability of this formation is judging from its soil composition.

carried out for considered larger

this than

formation. However, the that of Madhupur Clay,

pH: 7.2

Topographic conditions The project area in Dinajpur district, between Phulbari and Parbatipur is situated in the deltaic plain of the Jamuna and Padma Rivers. It is flat and its altitude is about 30 m above mean sea level, which is relatively higher than the other areas of Bangladesh.

0.2.3 Layouts The detailed arrangement shall consideration of easy maintenance, interfaces to the power grid.

be proposed access, short

by links

the Contractor for piling and

under cabling,

The plant area shall be developed upto existing plant level (if required). The ash pond shall be lowered below the natural ground for about 3 m and shall be provided with bud walls up to + 5 m above the natural ground. The park area shall remain at about natural ground level with the exception of the outfall canal.

0.2.4 Configuration One coal the Plant.

fired

boiler

with

turbine

generators

represent

the

core

components

of

The cooling requirement of the Plant shall be accomplished by a wet cooling tower system. For ash transport, the cooling tower blow down water shall be used. But for commissioning fresh water is required.

0.2.5 General technical requirements of the Plant 0.2.5.1 Design requirements The Plant shall be designed for base load operation. Also extended shorttime operation and longer periods of part load down to synchronized minimum load must be possible without restrictions. The design lifetime of the Plant shall exceed 200,000 operating hours. The thermodynamic process of the Plant Contractor according to the proposed equipment.

is

to

be

optimized

by

the

Tenderer/

The Plant shall be built-up of one independently operable power unit. An economic optimal balance between investment, maintenance Plant availability (planned and unplanned outages) shall be proposed .

expenses

2 8

and

Redundancy concept Due to the block-wise structure of the Plant, propose only 1 x 100% implementation of very cooling water pumps, compressors, etc., but by no water system. These moderate investment solutions can Contractor proves with corresponding spare that overall an optimum economic solution will 100% solutions are preferable.

be parts result;

the costly means

Tenderer/Contractor major equipment for the boiler

may like: feed

accepted if the Tenderer/ and maintenance proposals otherwise 3 x 50%, or 2x

The Tenderer/Contractor shall

a) design and configure all components of the Plant b) propose spare parts stock (spare part building and content) c) propose maintenance works in such a way that: • •

unplanned outage time of power unit shall not exceed 1.7% of the time in a calendar year Unit is available during 99.2% of the time in a calendar year.

0.2.5.2 Outline description of generating facilities a) Installed capacity

250 MW Net

b) Annual utilization factor

80%

c) Overall gross efficiency

38.0% (minimum) —

d) Plant starting scope e) Unit auxiliary consumption f) Annual coal consumption

output

el. at Gen. terminal

/input

coal net calorific value at all conditions of warm/hot or cold. 6.3% (max.) about 700,000 tons (approx.)

g) Ash disposal area (proposed) 3 75,000 m2 h) Design life time of the power Plant shall exceed 200,000 operating hours.

0.2.5.2 Main powerhouse including control building The main powerhouse which includes the control complex need to be a multilevel multi-area structure. It shall be a seismic proof building of conventional steel braced frame construction in the upper portion with foundations of reinforced concrete.

0.2.5.3 Civil

2 9

The area of the Power Station for protection against flooding is considered to befilled up to the existing plant level (if required) to protect the Power Plant against the flood. The coal storage area shall be paved. drained and partly covered. The drain shall be discharged to the ash pond. The ash pond shall be excavated. fertile soil to be stored aside and the pond shall be lined with clay. The ash pond overflow shall be treated to meet the relevant standards and shall lead via outfall canal to the Tillay river. Try ash storage shall be considered as an option. The treated sewage water may be discharged to the Tillay river. The ash pond and fences and gates.

the

park

shall

be

separated

from each

other

and

the

Plant

by

shall be operation

suitable for safe and economical under the extreme ambient air.

0.2.6 Mode of operation All the equipment and the facilities continuous and also for short-time water and coal conditions specified. The design of requirements:

the

Plant

shall

be

based

on

the

following

operation

and

dispatching

a) The power unit shall be capable of following the daily and seasonal demand profile of the electrical network.

b) The

power generation shall be fully dispatch able within the technical limits of the Plant to be specified by the Tenderer, but at least between 40% and 100% of the net power output of the Plant without supporting fire.

c) Full

compliance with the conditions of within 40 - 100% of power unit's power range.

the

admissible

air

pollution

is

required

0.2.7 Environmental conditions and emission control standards 0.2.7.1 Environmental conditions The present environmental conditions in Barapukuria are as follows:

a) Atmospheric quality There are no industrial activities to pollute air within a radius of 10 km from the planned Power Station site (except existing 2 x 125 MW coal fired units). Though there are effects of automobile, etc. emission and smoke generated by burning after harvesting and from houses, the air pollutant concentration is expected to be at a very low level.

b) Water quality As prospective raw water sources, Coal mine discharge water (for normal use) and wells (during emergency case to meet at least 50% of total requirement) are considered. Water quality is given in Annex.

3 0

c) Soil quality The study team collected the soil (in the year 1998) from the site for analysis and the results are as follows: Analysis result of metal content in soil MgO Item 0.7 Barapukuria soil

CaO

Na20

K2 0

0.2

2.2

%

0.2

Barapukuria soil

6.5

7

12.

+

m

CM

pS/c

+

CO 0

Analysis result of water dissolving and pH of soil Item pH Mg1 EC

B203 427

K+

mg/kg

Na +

201

b3+

mg/kg 0.1

0.2

0.2

1.0